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Sample records for metal pit waste

  1. Chemicals, metals, and pesticide pits waste unit low induction number electromagnetic survey

    Energy Technology Data Exchange (ETDEWEB)

    Cumbest, R.J.; Mohon, D.

    1995-06-01

    An electromagnetic survey was conducted at the Chemicals, Metals, and Pesticide Waste Unit to identify any buried metallic objects that may be present in the materials used to fill and cover the pits after removal of pit debris. The survey was conducted with a Geonics EM-31 Terrain Conductivity Meter along north - south oriented traverses with 5-ft station intervals to produce a 5-ft by 5-ft square grid node pattern. Both conductivity and in-phase components were measured at each station for vertical dipole orientation with the common axis of the dipoles in the north - south and east - west orientations. The conductivity data clearly show elevated conductivities (2.1 to 7.0 mS/m) associated with the material over the pits, as compared with the surrounding area that is characterized by lower conductivities (1 to 2 mS/m). This is probably the result of the higher clay content of the fill material relative to the surrounding area, which has a higher sand to clay ratio and the presence of a plastic cover beneath the fill that has probably trapped water. Many metal objects are present in the survey area including manhole covers, monitoring well heads, metal, signs, drain culverts, abandoned wells, and BP waste unit marker balls. AU of these exhibit associated conductivity and in-phase anomalies of various magnitude. In addition to these anomalies that can be definitely associated with surface sources, conductivity and in-phase anomalies are also present with no obvious surface source. These anomalies are probably indicative of subsurface buried metallic objects. A high concentration of these objects appears to be present in the southwest corner of the survey area.

  2. Gas cylinder disposal pit remediation waste minimization and management

    International Nuclear Information System (INIS)

    Alas, C.A.; Solow, A.; Criswell, C.W.; Spengler, D.; Brannon, R.; Schwender, J.M.; Eckman, C.K.; Rusthoven, T.

    1995-01-01

    A remediation of a gas cylinder disposal pit at Sandia National Laboratories, New Mexico has recently been completed. The cleanup prevented possible spontaneous releases of hazardous gases from corroded cylinders that may have affected nearby active test areas at Sandia's Technical Area III. Special waste management, safety, and quality plans were developed and strictly implemented for this project. The project was conceived from a waste management perspective, and waste minimization and management were built into the planning and implementation phases. The site layout was planned to accommodate light and heavy equipment, storage of large quantities of suspect soil, and special areas to stage and treat gases and reactive chemicals removed from the pit, as well as radiation protection areas. Excavation was a tightly controlled activity using experienced gas cylinder and reactive chemical specialists. Hazardous operations were conducted at night under lights, to allow nearby daytime operations to function unhindered. The quality assurance plan provided specific control of, and documentation for, critical decisions, as well as the record of daily operations. Both hand and heavy equipment excavation techniques were utilized. Hand excavation techniques were utilized. Hand excavation techniques allows sealed glass containers to be exhumed unharmed. In the end, several dozen thermal batteries; 5 pounds (2.3 kg) of lithium metal; 6.6 pounds (3.0 kg) of rubidium metal; several kilograms of unknown chemicals; 140 cubic yards (107 cubic meters) of thorium-contaminated soil; 270 cubic yards (205 cubic meters) of chromium-contaminated soil; and 450 gas cylinders, including 97 intact cylinders containing inert, flammable, toxic, corrosive, or oxidizing gases were removed and effectively managed to minimize waste

  3. Savannah River Site chemical, metal, and pesticide (CMP) waste vitrification treatability studies

    International Nuclear Information System (INIS)

    Cicero, C.A.

    1997-01-01

    Numerous Department of Energy (DOE) facilities, as well as Department of Defense (DOD) and commercial facilities, have used earthen pits for disposal of chemicals, organic contaminants, and other waste materials. Although this was an acceptable means of disposal in the past, direct disposal into earthen pits without liners or barriers is no longer a standard practice. At the Savannah River Site (SRS), approximately three million pounds of such material was removed from seven chemical, metal, and pesticide disposal pits. This material is known as the Chemical, Metal, and Pesticide (CMP) Pit waste and carries several different listed waste codes depending on the contaminants in the respective storage container. The waste is not classified as a mixed waste because it is believed to be non-radioactive; however, in order to treat the material in a non-radioactive facility, the waste would first have to be screened for radioactivity. The Defense Waste Processing Technology (DWPT) Section of the Savannah River Technology Center (SRTC) was requested by the DOE-Savannah River (SR) office to determine the viability of vitrification of the CMP Pit wastes. Radioactive vitrification facilities exist which would be able to process this waste, so the material would not have to be analyzed for radioactive content. Bench-scale treatability studies were performed by the DWPT to determine whether a homogeneous and durable glass could be produced from the CMP Pit wastes. Homogeneous and durable glasses were produced from the six pits sampled. The optimum composition was determined to be 68.5 wt% CMP waste, 7.2 wt% Na 2 O, 9 wt% CaO, 7.2 wt% Li 2 O and 8.1 wt% Fe 2 O 3 . This glass melted at 1,150 C and represented a two fold volume reduction

  4. Demonstration of In-Situ Stabilization of Buried Waste at Pit G-11 at the Brookhaven National laboratory Glass Pits Disposal Site

    International Nuclear Information System (INIS)

    Dwyer, B.P.; Gilbert, J.; Heiser, J.

    1999-01-01

    In 1989 BNL was added to the EPAs National Priorities List. The site is divided into seven operable units (OU). OU-I includes the former landfill area. The field task site is noted as the AOC 2C Glass Holes location. Beginning in the 1960s and continuing into the 1980s, BNL disposed of laboratory waste (glassware, chemicals and animal carcasses) in numerous shallow pits. The drivers for remediating the pits are; historical records that indicate hazardous materials may have been disposed of in the pits; ground water contamination down gradient of the pits; a test excavation of one of the glass holes that unearthed laboratory glass bottles with unidentified liquids still contained; and the fact that BNL rests atop an EPA designated sole-source aquifer. The specific site chosen for this demonstration was pit G-11. The requirements that lead to choosing this pit were; a well characterized pit and a relatively isolated pit where our construction operations would not impact on adjacent pits. The glass holes area, including pit G-11, was comprehensively surveyed using a suite of geophysical techniques (e.g., EM-31, EM-61, GPR). Prior to stabilizing the waste form a subsurface barrier was constructed to contain the entire waste pit. The pit contents were then stabilized using a cement grout applied via jet grouting. The stabilization was performed to make removal of the waste from the pit easier and safer in terms of worker exposure. The grouting process would mix and masticate the waste and grout and form a single monolithic waste form. This large monolith would then be subdivided into smaller 4 foot by 4 foot by 10-12 foot block using a demolition grout. The smaller blocks would then be easily removed from the site and disposed of in a CERCLA waste site

  5. Pitting growth rate in carbon steel exposed to simulated radioactive waste

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1995-01-01

    Dilute high-level radioactive waste slurries can induce pitting corrosion in carbon steel tanks in which such waste is stored and processed. The waste is normally maintained with closely monitored nitrite and hydroxide concentrations known to prevent the initiation of pitting. Coupon immersion are being conducted in laboratory simulants of waste to determine the probability and growth rate of pitting in steel in the event of below-limits nitrite concentrations. Sets of about 36 carbon steel coupons have been immersed in known corrosive conditions (nitrite < 5% of the established limit) at a temperature of 50 C. Three sets have been removed from testing after 64, 150, and 350 days of immersion. The long immersion times introduced variability in the exposure conditions due to the evaporation and replenishment of solution. The deepest corrosive attack was measured one each coupon by optical microscopy. The deepest pits were ranked and analyzed as a type 1 extreme value distribution to extrapolate from the coupon population to the maximum pit depths in a waste tank structure. The data were compared to a power law for pit growth, although the deepest pits did not increase monotonically with time in the limited data set

  6. INEL cold test pit demonstration of improvements in information derived from non-intrusive geophysical methods over buried waste sites

    International Nuclear Information System (INIS)

    1994-01-01

    Under Contract between US DOE Idaho National Engineering Laboratory (INEL) and the Blackhawk Geosciences Division of Coleman Research Corporation (BGD-CRC), geophysical investigations were conducted to improve the detection of buried wastes. Site characterization is a costly and time consuming process with the most costly components being drilling, sampling, and chemical analysis of samples. There is a focused effort at US DOE and other agencies to investigate methodologies that reduce costs and shorten the time between characterization and clean-up. These methodologies take the form of employing non-invasive (geophysical) and minimal invasive (e.g., cone penetrometer driving) techniques of characterization, and implementing a near real-time, rational decision-making process (Expedited Site Characterization). Over the Cold Test Pit (CTP) at INEL, data were acquired with multiple sensors on a dense grid. Over the CTP the interpretations inferred from geophysical data are compared with the known placement of various waste forms in the pit. The geophysical sensors employed were magnetics, frequency and time domain electromagnetics, and ground penetrating radar. Also, because of the high data density acquired, filtering and other data processing and imaging techniques were tested. The conclusions derived from the geophysical surveys were that pit boundaries, berms between cells within the pit, and individual objects placed in the pit were best mapped by the new Geonics EM61 time domain EM metal detector. Part of the reason for the effectiveness of the time domain metal detector is that objects buried in the pit are dominantly metallic. Also, the utility of geophysical data is significantly enhanced by dimensional and 3-dimensional imaging formats. These images will particularly assist remediation engineers in visualizing buried wastes

  7. Pitting growth rate in carbon steel exposed to simulated radioactive waste

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1996-06-01

    Dilute high-level radioactive waste slurries can induce pitting corrosion in carbon steel tanks in which such waste is stored and processed. The waste is normally maintained with closely monitored nitrite and hydroxide concentrations known to prevent the initiation of pitting. Coupon immersion tests are being conducted in laboratory simulants of waste to determine the probability and growth rate of pitting in steel in the event of out-of-limits nitrite concentrations. Sets of about 36 carbon steel coupons have been immersed in known corrosive conditions (nitrite < 5 per cent of the established limit) at a temperature of 50 degrees C. Three sets have been removed from testing after 64, 150, and 350 days of immersion. The long immersion times introduced variability in the exposure conditions due to the evaporation and replenishment of solution. The deepest corrosive attack was measured on each coupon by optical microscopy. The deepest pits were ranked and analyzed as a type 1 extreme value distribution to extrapolate from the coupon population to the maximum expected pit depths in a waste tank structure. The data were compared to a power law for pit growth, although the deepest pits did not increase monotonically with time in the limited data set

  8. Liquid waste processing from TRIGA spent fuel storage pits

    International Nuclear Information System (INIS)

    Buchtela, Karl

    1988-01-01

    At the Atominstitute of the Austrian Universities and also at other facilities running TRIGA reactors, storage pits for spent fuel elements are installed. During the last revision procedure, the reactor group of the Atominstitute decided to refill the storage pits and to get rid of any contaminated storage pit water. The liquid radioactive waste had been pumped to polyethylene vessels for intermediate storage before decontamination and release. The activity concentration of the storage pit water at the Aominstitute after a storage period of several years was about 40 kBq/l, the total amount of liquid in the storage pits was about 0.25 m 3 . It was attempted to find a simple and inexpensive method to remove especially the radioactive Cesium from the waste solution. Different methods for decontamination like distillation, precipitation and ion exchange are discussed

  9. Efficient utilization of waste date pits for the synthesis of green diesel and jet fuel fractions

    International Nuclear Information System (INIS)

    Al-Muhtaseb, Ala’a H.; Jamil, Farrukh; Al-Haj, Lamya; Al-Hinai, Mohab A.; Baawain, Mahad; Myint, Myo Tay Zar; Rooney, David

    2016-01-01

    Highlights: • Active catalysts Pt/C and Pd/C were developed from waste date pits. • Catalysts showed good activity in hydrodeoxygenation of date pit oil to alkane fuels. • The liquid product fractions lay within the range of the jet fuel and green diesel. • Green diesel fraction obtained by Pd/C was 72.03% and jet fuel was 30.39%. • Date pits can be a promising platform for the production of catalysts and biofuels. - Abstract: Date pits are considered one of the major agricultural wastes in Oman. The present work involves the synthesis of active catalysts from waste date pits carbon produced by carbonization and impregnation with Pt and Pd metals. Synthesized catalysts Pt/C and Pd/C were characterized by XRD, SEM, TEM, EDX, BET and XPS. The activity of the catalysts’ performance was evaluated by the hydrodeoxygenation of date pits oil for the production of second-generation biofuels, which includes jet fuel and green diesel fractions. Results indicate that the synthesized catalysts were highly active for the hydrodeoxygenation of date pits oil. Based on the elemental analysis, the degree of deoxygenation (DOD) of product oil was 97.5% and 89.4% for the Pd/C and Pt/C catalysts respectively. The high DOD was also confirmed by product analyses that mainly consist of paraffinic hydrocarbons. Results also showed that between the two catalysts, Pd/C showed a higher activity towards hydrodeoxygenation, a conclusion that was based on the high DOD of the product oil due to hydrocarbons formation. Based on the type of components in the product oil, the maximum fraction of hydrocarbons formed lay within the range of 72.03% and 72.78% green diesel, and 30.39% and 28.25% jet fuel using Pd/C and Pt/C catalysts respectively. It can be concluded that waste date pits can be a promising platform for the production of catalysts and biofuels.

  10. Investigating oiled birds from oil field waste pits

    International Nuclear Information System (INIS)

    Gregory, D.G.; Edwards, W.C.

    1991-01-01

    Procedures and results of investigations concerning the oiling of inland raptors, migratory water-fowl and other birds are presented. Freon washings from the oiled birds and oil from the pits were analyzed by gas chromatography. In most instances the source of the oil could be established by chromatographic procedures. The numbers of birds involved (including many on the endangered species list) suggested the need for netting or closing oil field waste pits and mud disposal pits. Maintaining a proper chain of custody was important

  11. State Waste Discharge Permit application: 200-W Powerhouse Ash Pit

    Energy Technology Data Exchange (ETDEWEB)

    Atencio, B.P.

    1994-06-01

    As part of the Hanford Federal Facility Agreement and Consent Order negotiations; the US Department of Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site which affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173-216 (or 173-218 where applicable) of the Washington Administrative Code, the State Waste Discharge Permit Program. This document constitutes the State Waste Discharge Permit application for the 200-W Powerhouse Ash Pit. The 200-W Powerhouse Ash Waste Water discharges to the 200-W Powerhouse Ash Pit via dedicated pipelines. The 200-W Powerhouse Ash Waste Water is the only discharge to the 200-W Powerhouse Ash Pit. The 200-W Powerhouse is a steam generation facility consisting of a coal-handling and preparation section and boilers.

  12. State Waste Discharge Permit application: 200-E Powerhouse Ash Pit

    Energy Technology Data Exchange (ETDEWEB)

    Atencio, B.P.

    1994-06-01

    As part of the Hanford Federal Facility Agreement and Consent Order negotiations, the US Department and Energy, Richland Operations Office, the US Environmental Protection Agency, and the Washington State Department of Ecology agreed that liquid effluent discharges to the ground on the Hanford Site which affect groundwater or have the potential to affect groundwater would be subject to permitting under the structure of Chapter 173-216 (or 173-218 where applicable) of the Washington Administrative Code, the State Waste Discharge Permit Program. This document constitutes the State Waste Discharge Permit application for the 200-E Powerhouse Ash Pit. The 200-E Powerhouse Ash Waste Water discharges to the 200-E Powerhouse Ash Pit via dedicated pipelines. The 200-E Ash Waste Water is the only discharge to the 200-E Powerhouse Ash Pit. The 200-E Powerhouse is a steam generation facility consisting of a coal-handling and preparation section and boilers.

  13. Inhibiting pitting corrosion in carbon steel exposed to dilute radioactive waste slurries

    International Nuclear Information System (INIS)

    Zapp, P.E.; Hobbs, D.T.

    1991-01-01

    Dilute caustic high-level radioactive waste slurries can induce pitting corrosion in carbon steel. Cyclic potentiodynamic polarization tests were conducted in simulated and actual waste solutions to determine minimum concentrations of sodium nitrate which inhibit pitting in ASTM A537 class 1 steel exposed to these solutions. Susceptibility to pitting was assessed through microscopic inspection of specimens and inspection of polarization scans. Long-term coupon immersion tests were conducted to verify the nitrite concentrations established by the cyclic potentiodynamic polarization tests. The minimum effective nitrite concentration is expressed as a function of the waste nitrate concentration and temperature

  14. Evapotranspiration Cover for the 92-Acre Area Retired Mixed Waste Pits:Interim CQA Report

    International Nuclear Information System (INIS)

    2011-01-01

    This Interim Construction Quality Assurance (CQA) Report is for the 92-Acre Evapotranspiration Cover, Area 5 Waste Management Division (WMD) Retired Mixed Waste Pits, Nevada National Security Site, Nevada for the period of January 20, 2011 to May 12, 2011. This Interim Construction Quality Assurance (CQA) Report is for the 92-Acre Evapotranspiration Cover, Area 5 Waste Management Division (WMD) Retired Mixed Waste Pits, Nevada National Security Site, Nevada for the period of January 20, 2011 to May 12, 2011. Construction was approved by the Nevada Division of Environmental Protection (NDEP) under the Approval of Corrective Action Decision Document/Corrective Action Plan (CADD/CAP) for Corrective Action Unit (CAU) 111: Area 5 WMD Retired Mixed Waste Pits, Nevada National Security Site, Nevada, on January 6, 2011, pursuant to Subpart XII.8a of the Federal Facility Agreement and Consent Order. The project is located in Area 5 of the Radioactive Waste Management Complex (RWMC) at the Nevada National Security Site (NNSS), formerly known as the Nevada Test Site, located in southern Nevada, approximately 65 miles northwest of Las Vegas, Nevada, in Nye County. The project site, in Area 5, is located in a topographically closed basin approximately 14 additional miles north of Mercury Nevada, in the north-central part of Frenchman Flat. The Area 5 RWMS uses engineered shallow-land burial cells to dispose of packaged waste. The 92-Acre Area encompasses the southern portion of the Area 5 RWMS, which has been designated for the first final closure operations. This area contains 13 Greater Confinement Disposal (GCD) boreholes, 16 narrow trenches, and 9 broader pits. With the exception of two active pits (P03 and P06), all trenches and pits in the 92-Acre Area had operational covers approximately 2.4 meters thick, at a minimum, in most areas when this project began. The units within the 92-Acre Area are grouped into the following six informal categories based on physical location

  15. Evapotranspiration Cover for the 92-Acre Area Retired Mixed Waste Pits:Interim CQA Report

    Energy Technology Data Exchange (ETDEWEB)

    The Delphi Groupe, Inc., and J. A. Cesare and Associates, Inc.

    2011-06-20

    This Interim Construction Quality Assurance (CQA) Report is for the 92-Acre Evapotranspiration Cover, Area 5 Waste Management Division (WMD) Retired Mixed Waste Pits, Nevada National Security Site, Nevada for the period of January 20, 2011 to May 12, 2011. This Interim Construction Quality Assurance (CQA) Report is for the 92-Acre Evapotranspiration Cover, Area 5 Waste Management Division (WMD) Retired Mixed Waste Pits, Nevada National Security Site, Nevada for the period of January 20, 2011 to May 12, 2011. Construction was approved by the Nevada Division of Environmental Protection (NDEP) under the Approval of Corrective Action Decision Document/Corrective Action Plan (CADD/CAP) for Corrective Action Unit (CAU) 111: Area 5 WMD Retired Mixed Waste Pits, Nevada National Security Site, Nevada, on January 6, 2011, pursuant to Subpart XII.8a of the Federal Facility Agreement and Consent Order. The project is located in Area 5 of the Radioactive Waste Management Complex (RWMC) at the Nevada National Security Site (NNSS), formerly known as the Nevada Test Site, located in southern Nevada, approximately 65 miles northwest of Las Vegas, Nevada, in Nye County. The project site, in Area 5, is located in a topographically closed basin approximately 14 additional miles north of Mercury Nevada, in the north-central part of Frenchman Flat. The Area 5 RWMS uses engineered shallow-land burial cells to dispose of packaged waste. The 92-Acre Area encompasses the southern portion of the Area 5 RWMS, which has been designated for the first final closure operations. This area contains 13 Greater Confinement Disposal (GCD) boreholes, 16 narrow trenches, and 9 broader pits. With the exception of two active pits (P03 and P06), all trenches and pits in the 92-Acre Area had operational covers approximately 2.4 meters thick, at a minimum, in most areas when this project began. The units within the 92-Acre Area are grouped into the following six informal categories based on physical location

  16. CMP [Chemicals, Metals, and Pesticides] Pits: Environmental information document

    International Nuclear Information System (INIS)

    Scott, S.C.; Kolb, N.L.; Price, V.; Bledsoe, H.W.

    1986-12-01

    This document provides environmental information on postulated closure options for the Chemicals, Metals, and Pesticides (CMP) Pits at the Savannah River Plant and was developed as background technical documentation for the Department of Energy's proposed Environmental Impact Statement (EIS) on waste management activities for groundwater protection at the plant. The results of groundwater and atmospheric pathway analyses, accident analysis, and other environmental assessments discussed in this document are based upon a conservative analysis of all foreseeable scenarios as defined by the National Environmental Policy Act (40 CFR 1500-1508). The scenarios do not necessarily represent actual environmental conditions. This document is not meant to be used as a regulatory closure plan or other regulatory document to comply with required federal or state environmental regulations

  17. Evapotranspiration Cover for the 92-Acre Area Retired Mixed Waste Pits, Area 5 Waste Management Division, Nevada National Security Site, Final CQA Report

    International Nuclear Information System (INIS)

    2012-01-01

    The report is the Final Construction Quality Assurance (CQA) Report for the 92-Acrew Evapotranspiration Cover, Area 5 Waste Management Division Retired Mixed Waste Pits, Nevada National Security Site, Nevada, for the period of January 20, 2011, to January 31, 2012 The Area 5 RWMS uses engineered shallow-land burial cells to dispose of packaged waste. The 92-Acre Area encompasses the southern portion of the Area 5 RWMS, which has been designated for the first final closure operations. This area contains 13 Greater Confinement Disposal (GCD) boreholes, 16 narrow trenches, and 9 broader pits. With the exception of two active pits (P03 and P06), all trenches and pits in the 92-Acre Area had operational covers approximately 2.4 meters thick, at a minimum, in most areas when this project began. The units within the 92-Acre Area are grouped into the following six informal categories based on physical location, waste types and regulatory requirements: (1) Pit 3 Mixed Waste Disposal Unit (MWDU); (2) Corrective Action Unit (CAU) 111; (3) CAU 207; (4) Low-level waste disposal units; (5) Asbestiform low-level waste disposal units; and (6) One transuranic (TRU) waste trench.

  18. Remaining Sites Verification Package for the 128-B-2, 100-B Burn Pit No.2 Waste Site. Attchment to Waste Site Reclassification Form 2005-038

    International Nuclear Information System (INIS)

    Carlson, R.A.

    2005-01-01

    The 128-B-2 waste site was a burn pit historically used for the disposal of combustible and noncombustible wastes, including paint and solvents, office waste, concrete debris, and metallic debris. This site has been remediated by removing approximately 5,627 bank cubic meters of debris, ash, and contaminated soil to the Environmental Restoration Disposal Facility. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River

  19. Near-field microwave detection of corrosion precursor pitting under thin dielectric coatings in metallic substrate

    International Nuclear Information System (INIS)

    Hughes, D.; Zoughi, R.; Austin, R.; Wood, N.; Engelbart, R.

    2003-01-01

    Detection of corrosion precursor pitting on metallic surfaces under various coatings and on bare metal is of keen interest in evaluation of aircraft fuselage. Near-field microwave nondestructive testing methods, utilizing open-ended rectangular waveguides and coaxial probes, have been used extensively for detection of surface flaws in metals, both on bare metal and under a dielectric coating. This paper presents the preliminary results of using microwave techniques to detect corrosion precursor pitting under paint and primer, applique and on bare metal. Machined pits of 500 μm diameter were detected using open-ended rectangular waveguides at V-Band under paint and primer and applique, and on bare metal. Using coaxial probes, machined pits with diameters down to 150 μm on bare metal were also detected. Relative pit size and density were shown on a corrosion-pitted sample using open-ended rectangular waveguides at frequencies of 35 GHz to 70 GHz. The use of Boeing's MAUS TM scanning systems provided improved results by alleviating standoff variation and scanning artifact. Typical results of this investigation are also presented

  20. Utilization of open pit burned household waste ash--a feasibility study in Dhaka.

    Science.gov (United States)

    Haque, Md Obaidul; Sharif, Ahmed

    2014-05-01

    Informal incineration or open pit burning of waste materials is a common practice in the peripheral area of Dhaka, one of the fastest growing mega-cities in the world. This study deals with the effect of open pit burned (i.e. open burned) household waste bottom ash on fired clay bricks. Between 0 to 50% (by weight) of open pit burned household waste bottom ash was mixed with clay to make bricks. The molded specimens were air-dried at room temperature for 24 h and then oven dried at 100 °C for another 24 h to remove the water. The raw bricks were fired in a muffle furnace to a designated temperature (800, 900 and 1000 °C, respectively). The firing behaviour (mechanical strength, water absorption and shrinkage) was determined. The microstructures, phase compositions and leachates were evaluated for bricks manufactured at different firing temperatures. These results demonstrate that open pit burned ash can be recycled in clay bricks. This study also presents physical observations of the incinerated ash particles and determination of the chemical compositions of the raw materials by wet analysis. Open pit burned ash can be introduced easily into bricks up to 20% wt. The concentrations of hazardous components in the leachates were below the standard threshold for inert waste category landfill and their environmental risk during their use-life step can be considered negligible.

  1. Stochastic simulation of pitting degradation of multi-barrier waste container in the potential repository at Yucca Mountain

    International Nuclear Information System (INIS)

    Lee, J.H.; Atkins, J.E.; Andrews, R.W.

    1995-01-01

    A detailed stochastic waste package degradation simulation model was developed incorporating the humid-air and aqueous general and pitting corrosion models for the carbon steel corrosion-allowance outer barrier and aqueous pitting corrosion model for the Alloy 825 corrosion-resistant inner barrier. The uncertainties in the individual corrosion models were also incorporated to capture the variability in the corrosion degradation among waste packages and among pits in the same waste package. Within the scope of assumptions employed in the simulations, the corrosion modes considered, and the near-field conditions from the drift-scale thermohydrologic model, the results of the waste package performance analyses show that the current waste package design appears to meet the 'controlled design assumption' requirement of waste package performance, which is currently defined as having less than 1% of waste packages breached at 1,000 years. It was shown that, except for the waste packages that fail early, pitting corrosion of the corrosion-resistant inner barrier has a greater control on the failure of waste packages and their subsequent degradation than the outer barrier. Further improvement and substantiation of the inner barrier pitting model (currently based on an elicitation) is necessary in future waste package performance simulation model

  2. Research process of nondestructive testing pitting corrosion in metal material

    Directory of Open Access Journals (Sweden)

    Bo ZHANG

    2017-12-01

    Full Text Available Pitting corrosion directly affects the usability and service life of metal material, so the effective nondestructive testing and evaluation on pitting corrosion is of great significance for fatigue life prediction because of data supporting. The features of pitting corrosion are elaborated, and the relation between the pitting corrosion parameters and fatigue performance is pointed out. Through introducing the fundamental principles of pitting corrosion including mainly magnetic flux leakage inspection, pulsed eddy current and guided waves, the research status of nondestructive testing technology for pitting corrosion is summarized, and the key steps of nondestructive testing technologies are compared and analyzed from the theoretical model, signal processing to industrial applications. Based on the analysis of the signal processing specificity of different nondestructive testing technologies in detecting pitting corrosion, the visualization combined with image processing and signal analysis are indicated as the critical problems of accurate extraction of pitting defect information and quantitative characterization for pitting corrosion. The study on non-contact nondestructive testing technologies is important for improving the detection precision and its application in industries.

  3. Effect of nitrite concentration on pit depth in carbon steel exposed to simulated radioactive waste

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1997-01-01

    The growth of pits in carbon steel exposed to dilute (0.055 M nitrate-bearing) alkaline salt solutions that simulate radioactive waste was investigated in coupon immersion tests. Most coupons were tested in the as-received condition, with the remainder having been heat treated to produce an oxide film. Nitrite, which is an established pitting inhibitor in these solutions, was present in concentrations from 0 to 0.031 M to 0.16 M; the last concentration is known to prevent pitting initiation in the test solution at the 50 degrees C test temperature. The depths of the deepest pits on coupons of particular exposure conditions were measure microscopically and were analyzed as simple, type 1 extreme value statistical distributions, to predict the deepest expected pit in a radioactive waste tank subject to the test conditions. While the growth rate of pits could not be established from these tests, the absolute value of the deepest pits predicted is of the order of 100 mils after 448 days of exposure. The data indicate that even nitrite concentrations insufficient to prevent pitting have a beneficial effect on limiting the growth of deepest pits

  4. Superfund record of decision (EPA Region 4): Whitehouse Waste Oil Pits Site, Duval County, Jacksonville, FL. (First remedial action), (Amendment), June 1992. Final report

    International Nuclear Information System (INIS)

    1992-01-01

    The 7-acre Whitehouse Waste Oil Pits site was used by Allied Petroleum Products (Allied) to dispose of acidic waste oil sludges from its oil reclamation process in Whitehouse, Duval County, Florida. A cypress swamp system and residential area are immediately adjacent to the site. The acid sludge produced in the first step and clay used to decolorize the oil were dumped into the unlined pits at the site. A 1985 ROD addressed source control as a containment remedy consisting of a slurry wall construction, soil cap, and a ground water recovery and treatment system; however, EPA has re-evaluated the 1985 ROD selection and determined that the containment remedy failed to meet the requirements of SARA. As a result, the ROD Amendment focuses on an alternative for treating Whitehouse wastes by eliminating direct contact risk associated with pit soil/sludge wastes and preventing contaminated ground water in the surficial aquifer from migrating laterally. The primary contaminants of concern that affect the soil, sediment, surface water, and ground water are VOCs, including benzene, toluene, and xylenes; organics, including PCBs and phenols; and metals, including arsenic, chromium, and lead. The amended remedial action for the site are included

  5. Effect of chloride concentration and pH on pitting corrosion of waste package container materials

    International Nuclear Information System (INIS)

    Roy, A.K.; Fleming, D.L.; Gordon, S.R.

    1996-12-01

    Electrochemical cyclic potentiodynamic polarization experiments were performed on several candidate waste package container materials to evaluate their susceptibility to pitting corrosion at 90 degrees C in aqueous environments relevant to the potential underground high-level nuclear waste repository. Results indicate that of all the materials tested, Alloy C-22 and Ti Grade-12 exhibited the maximum corrosion resistance, showing no pitting or observable corrosion in any environment tested. Efforts were also made to study the effect of chloride ion concentration and pH on the measured corrosion potential (Ecorr), critical pitting and protection potential values

  6. Ecological risk of reprocessing of uranium wastes of the Gafurov's tailing pit

    International Nuclear Information System (INIS)

    Khakimov, N.; Nazarov, Kh.M.; Kamalov, D.D.; Mirsaidov, U.M.

    2010-01-01

    Present article is devoted to assessment ecological risk of reprocessing of uranium wastes of the Gafurov's tailing pit. Authors set as their purpose the investigation of ecological risk of reprocessing of uranium wastes of the Gafurov-city's tailing pit. Having carried out their investigations, the authors came to the conclusion that the effect of radon gas during reprocessing to workers and specialists is minimal if they follow all the required safety rules.

  7. The United States pit disassembly and conversion project -- Meeting the MOX fuel specification

    International Nuclear Information System (INIS)

    Nelson, T.O.; James, C.A.; Kolman, D.G.

    1998-01-01

    The US is actively involved in demonstrating the disassembly of nuclear weapons pits to an unclassified form readied for disposition. The MOX option is the most likely path forward for plutonium that originated from nuclear weapon pits. The US demonstration line for pit disassembly and conversion is known as ARIES, the advanced recovery and integrated extraction system. The ARIES demonstration line is being used to gather data in an integrated fashion of the technologies needed for pit disassembly and conversion. These activities include the following modules: pit bisection, hydride-dehydride, oxide conversion, canning, electrolytic decontamination, and nondestructive assay (NDA). Pit bisection swages in a pit in half. Hydride-dehydride converts the pit plutonium metal to an unclassified metal button. To convert the plutonium metal to an oxide the US is investigating a number of options. The primary oxide conversion approach involves variations of combining plutonium hydriding and subsequent oxidation. Another approach is to simply oxidize the metal under controlled conditions-direct metal oxidation (DMO). To remove the gallium from the plutonium oxide, a thermal distillation approach is being used. These pyrochemical approaches will substantially reduce the wastes produced for oxide conversion of weapon plutonium, compared to traditional aqueous processing. The packaging of either the plutonium metal or oxide to long term storage criteria involves the canning and electrolytic decontamination modules. The NDA suite of instruments is then used to assay the material in the containers, which enables international verification without the need to open the containers and repackage them. All of these processes are described

  8. Use of abandoned coal/lignite open pits for waste disposal in selected European countries

    International Nuclear Information System (INIS)

    Libicki, J.S.

    1989-01-01

    The use of abandoned coal/lignite pits as disposal sites for solid waste appears to be a reasonable approach to a difficult problem, especially if they are located close to the waste source. However, a potential for groundwater and soil pollution exists. This issue was discussed by a Group of Experts on Opencast Mining of the UN Economic Commission for Europe because most of the sites are operated by mining companies. This paper contains the major topics of discussion including the significance of the problem, legal aspects, characteristics of the open pits, waste intended for disposal, investigations required to obtain a disposal permit, disposal techniques, protection measures, monitoring environmental impacts, and research trends. A few countries are used as examples

  9. PIT 9 Project: A private sector initiative

    International Nuclear Information System (INIS)

    Macdonald, D.W.; Hughes, F.P.; Burton, B.N.

    1993-01-01

    The Pit 9 Comprehensive Demonstration is intended to demonstrate a cost-effective approach to remediate an Idaho National Engineering Lab. (INEL) waste disposal pit through a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Interim Action. The remediation will include additional requirements, if needed, to provide high confidence that only minor additional work would be necessary to accomplish the final closure as part of the overall final closure strategy for the INEL's Subsurface Disposal Area (SDA). Pit 9 is an inactive waste disposal pit located in the northeastern corner of the SDA at the INEL's Radioactive Waste Management Complex (RWMC). It covers approximately 1 acre. The waste within Pit 9 is primarily transuranic waste generated at the Rocky Flats Plant and additional wastes, both hazardous and low-level radioactive, from generators at the INEL

  10. Studies of corrosion in metallic container for storage of high level radioactive wastes

    International Nuclear Information System (INIS)

    Azkarate, I.; Madina, V.; Insausti, M.

    1999-01-01

    The metallic container is one of the most important barriers that, along with engineered and natural barriers, will isolate high level nuclear waste in saline and granite geological formations from the geosphere. However, general and localized corrosion modes such as stress corrosion cracking (SCC), pitting, crevice corrosion and hydrogen damage can be active under disposal conditions, so the corrosion behaviour of the metal container material must be carefully studied. Several metals and their alloys have been proposed for the fabrication of nuclear waste containers including carbon steels, stainless steels, titanium and titanium alloys and copper and copper-base alloys. Carbon steels and copper alloys are considered for the two rock formations, titanium is considered for salt environments and the stainless steel only in the case of a granite formation. (Author)

  11. Microstructure and pitting corrosion of 13CrNiMo weld metals

    International Nuclear Information System (INIS)

    Bilmes, P.D.; Llorente, C.L.; Saire Huaman, L.; Gassa, L.M.; Gervasi, C.A.

    2006-01-01

    Cyclic potentiodynamic measurements and scanning electron microscopy were used to analyze susceptibility to pitting corrosion of 13CrNiMo weld metals. In order to carry out a critical assessment of the influence of microstructural factors on localized corrosion, different heat treatments were applied to the alloys under investigation. Volume fractions of austenite in tempered conditions as well as the amount and size of precipitated carbides strongly affect pitting resistance. Characteristic potentials (pitting potential and repassivation potential) increase according to the retained austenite content. Results can be discussed in terms of a model that describes the structural refinement resulting from a double-tempering procedure

  12. Slope Stability Analysis of Waste Dump in Sandstone Open Pit Osielec

    Science.gov (United States)

    Adamczyk, Justyna; Cała, Marek; Flisiak, Jerzy; Kolano, Malwina; Kowalski, Michał

    2013-03-01

    This paper presents the slope stability analysis for the current as well as projected (final) geometry of waste dump Sandstone Open Pit "Osielec". For the stability analysis six sections were selected. Then, the final geometry of the waste dump was designed and the stability analysis was conducted. On the basis of the analysis results the opportunities to improve the stability of the object were identified. The next issue addressed in the paper was to determine the proportion of the mixture containing mining and processing wastes, for which the waste dump remains stable. Stability calculations were carried out using Janbu method, which belongs to the limit equilibrium methods.

  13. Limited mobility of dioxins near San Jacinto super fund site (waste pit) in the Houston Ship Channel, Texas due to strong sediment sorption.

    Science.gov (United States)

    Louchouarn, Patrick; Seward, Shaya M; Cornelissen, Gerard; Arp, Hans Peter H; Yeager, Kevin M; Brinkmeyer, Robin; Santschi, Peter H

    2018-02-20

    Sediments from a waste pit in Houston Ship Channel (HSC) were characterized using a number of molecular markers of natural organic matter fractions (e.g., pyrogenic carbon residues, PAHs, lignins), in addition to dioxins, in order to test the hypothesis that the dispersal and mobility of dioxins from the waste pit in the San Jacinto River is minimal. Station SG-6, sampled at the site of the submerged waste pit, had the highest dioxin/furan concentrations reported for the Houston Ship Channel/Galveston Bay (HSC/GB) system (10,000-46,000 pg/g), which translated into some of the highest reported World Health Organization Toxic Equivalents (TEQs: 2000-11,000 pg/g) in HSC sediments. Using a multi-tracer approach, this study confirmed our hypothesis that sludges from chlorinated pulps are a very likely source of dioxins/furans to this pit. However, this material also contained large quantities of additional hydrophobic organic contaminants (PAHs) and pyrogenic markers (soot-BC, levoglucosan), pointing to the co-occurrence of petroleum hydrocarbons and combustion byproducts. Comparison of dioxin/furan signatures in the waste pit with those from sediments of the HSC and a control site suggests that the remobilization of contaminated particles did not occur beyond the close vicinity of the pit itself. The dioxins/furans in sediments outside the waste pit within the HSC are rather from other diffuse inputs, entering the sedimentary environment through the air and water, and which are comprised of a mixture of industrial and municipal sources. Fingerprinting of waste pit dioxins indicates that their composition is typical of pulp and paper sources. Measured pore water concentrations were 1 order of magnitude lower than estimated values, calculated from a multiphase sorption model, indicating low mobility of dioxins within the waste pit. This is likely accomplished by co-occurring and strong sorbing pyrogenic and petrogenic residues in the waste pit, which tend to keep

  14. Burning/Rubble Pits: Environmental information document

    International Nuclear Information System (INIS)

    Huber, L.A.; Johnson, W.F.; Marine, I.W.

    1987-03-01

    The Burning/Rubble Pits, located near each of the major operating areas at the Savannah River Plant (SRP), began collecting burnable waste in 1951. The waste was incinerated monthly. All Burning/Rubble Pits are currently closed except for Burning/Rubble Pit 131-1R, which has not been backfilled but is inactive. No soil cores from the Burning/Rubble Pits have been analyzed. There are four groundwater monitoring wells located around each of the pits, which have been sampled quarterly since 1984. The closure options considered for the Burning/Rubble Pits are waste removal and closure, no waste removal and closure, and no action. Modeling calculations were made to determine the risks to human population for the three postulated closure options. An ecological assessment was conducted to predict the environmental impacts on aquatic and terrestrial biota. The relative costs for each of the closure options were estimated. An evaluation of the environmental impacts from the Burning/Rubble Pits indicates that the relative risks to human health and ecosystems for the postulated closure options are low. The ecological assessment shows that the effects of any closure activities on river water quality and wildlife would be insignificant. The cost estimates show the waste removal and closure option to be the most expensive for all of the pits. 38 refs., 35 figs., 47 tabs

  15. Corrective Action Investigation Plan for Corrective Action Unit 140: Waste Dumps, Burn Pits, and Storage Area, Nevada Test Site, Nevada, July 2002, Rev. No. 0

    International Nuclear Information System (INIS)

    2002-01-01

    This Corrective Action Investigation Plan contains the U.S. Department of Energy, National Nuclear Security Administration Nevada Operations Office's approach to collect the data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 140 under the Federal Facility Agreement and Consent Order. Corrective Action Unit 140 consists of nine Corrective Action Sites (CASs): 05-08-01, Detonation Pits; 05-08-02, Debris Pits; 05-17-01, Hazardous Waste Accumulation Site (Buried); 05-19-01, Waste Disposal Site; 05-23-01, Gravel Gertie; 05-35-01, Burn Pit; 05-99-04, Burn Pit; 22-99-04, Radioactive Waste Dump; 23-17-01, Hazardous Waste Storage Area. All nine of these CASs are located within Areas 5, 22, and 23 of the Nevada Test Site (NTS) in Nevada, approximately 65 miles northwest of Las Vegas. This CAU is being investigated because disposed waste may be present without appropriate controls (i.e., use restrictions, adequate cover) and hazardous and/or radioactive constituents may be present or migrating at concentrations and locations that could potentially pose a threat to human health and the environment. The NTS has been used for various research and development projects including nuclear weapons testing. The CASs in CAU 140 were used for testing, material storage, waste storage, and waste disposal. A two-phase approach has been selected to collect information and generate data to satisfy needed resolution criteria and resolve the decision statements. Phase I will determine if contaminants of potential concern (COPCs) are present in concentrations exceeding preliminary action levels. This data will be evaluated at all CASs. Phase II will determine the extent of the contaminant(s) of concern (COCs). This data will only be evaluated for CASs with a COC identified during Phase I. Based on process knowledge, the COPCs for CAU 140 include volatile organics, semivolatile organics, petroleum hydrocarbons, explosive residues

  16. Comparison between Windrow and Pit Composting of Poultry Wastes, Leaves and Garbage of Municipal Solid Waste in Damghan, Iran

    Directory of Open Access Journals (Sweden)

    Yaghmaeian K, Malakootian M, Noorisepehr M

    2005-01-01

    Full Text Available Basic principles of Integrated Solid Waste Management (ISWM are: Reduction, Reuse, Recycling and Recovery (4Rs. Composting as an element of ISWM strategy that can be applied to separately collected or mixed wastes, is a controlled aerobic process carried out by successive microbial populations combining both mesophilic and thermophilic activities and leading to the production of carbon dioxide, water, minerals and stabilized organic matter. In this research, comparing between windrow and pit co-composting methods was studied in the city of Damghan, Iran. Waste proportioning was done based on C/N ratio (about 25:1 and moisture content (about 55%. Mixed wastes were located in windrow and pit with natural aeration tunnel. Sufficient oxygen supply was provided in the piles of compostable materials in two systems through frequent turning of the piles in 7 d intervals during the first month. Temperature reached to maximum level in 10-15 d and then depleted (days: 20-25. It reached to the safety level (about 60˚C based on U.S.EPA and WHO recommendations. Finally, compost was produced with pH=7.7, dark brown color and 30- 35% moisture content. N, P, K, organic matter and organic carbon were measured by standard methods. Results were compared with WHO and U.S.EPA recommendations showing suitable conditions Also it was indicated that pit method was better for maintaining temperature, nitrogen, organic C and organic matter.

  17. Report on research cooperation for bio-aided treatment of waste water from pits, conducted in FY1997; 1997 nendo bio riyo ni yoru kohaisui shori gijutsu ni kansuru kenkyu kyoryoku hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    This research cooperation promotion project was implemented to develop techniques for preventing water pollution by waste water from pits in mines in China and thereby contributing to environmental preservation by studying to select optimum bacteria, culture the bacteria for high-efficient oxidation of iron, efficiently remove heavy metals from waste water, develop waste water treatment techniques with the aid of the iron-oxidizing bacteria, suitable for the mines in China, and develop techniques for recovering useful resources. The bio-aided waste water treatment process is a suitable method for treating waste water discharged from mining pits, in which ferrous iron present in waste water is oxidized with the aid of iron-oxidizing bacteria growing with ferrous ion as the energy source into ferric iron, which is precipitated at a low pH and removed in the presence of inexpensive calcium carbonate as the neutralizer. The pilot plant has been operating smoothly in a mode to treat waste water discharged from mining pits in Wushan Mine, almost satisfying the targets of treated water properties, i.e., pH: 0.5 or less, Cu: less than 0.5, Zn: less than 2.0, Pb: less than 1.0, Cd: less than 0.1, As: less than 0.5, Mn: less than 2.0, and SS: less than 70, all in mg/L except for pH. (NEDO)

  18. W-12 valve pit decontamination demonstration

    International Nuclear Information System (INIS)

    Benson, C.E.; Parfitt, J.E.; Patton, B.D.

    1995-12-01

    Waste tank W-12 is a tank in the ORNL Low-Level Liquid Waste (LLLW) system that collected waste from Building 3525. Because of a leaking flange in the discharge line from W-12 to the evaporator service tank (W-22) and continual inleakage into the tank from an unknown source, W-12 was removed from service to comply with the Federal Facilities Agreement requirement. The initial response was to decontaminate the valve pit between tank W-12 and the evaporator service tank (W-22) to determine if personnel could enter the pit to attempt repair of the leaking flange. Preventing the spread of radioactive contamination from the pit to the environment and to other waste systems was of concern during the decontamination. The drain in the pit goes to the process waste system; therefore, if high-level liquid waste were generated during decontamination activities, it would have to be removed from the pit by means other than the available liquid waste connection. Remote decontamination of W-12 was conducted using the General Mills manipulator bridge and telescoping trolley and REMOTEC RM-10 manipulator. The initial objective of repairing the leaking flange was not conducted because of the repair uncertainty and the unknown tank inleakage. Rather, new piping was installed to empty the W-12 tank that would bypass the valve pit and eliminate the need to repair the flange. The radiological surveys indicated that a substantial decontamination factor was achieved

  19. Carburization behavior under the pits induced by metal dusting in 304L and 347 stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chia-Hao [Department of Materials Engineering and Science, National Cheng Kung University, Tainan 701, Taiwan (China); Tsai, Wen-Ta, E-mail: wttsai@mail.ncku.edu.tw [Department of Materials Engineering and Science, National Cheng Kung University, Tainan 701, Taiwan (China)

    2009-08-15

    The metal dusting behavior of Type 304L and 347 stainless steels (SSs) in a flowing mixed CO/H{sub 2}/H{sub 2}O gas stream at 600 deg. C was investigated. After exposure in a 35% CO + 60% H{sub 2} + 5% H{sub 2}O gas for 500 h, large pits were formed on both steel surfaces. The aspect ratio of the pits formed in 304L SS was higher than that of the pits formed in 347 SS. The microstructures and chemical compositions of the reaction products and those of the substrate under the pits were examined by using a scanning electron microscope (SEM) combined with an energy dispersive spectrometer (EDS). A Cr-depleted zone containing voids was formed on the outer surface just beneath the pit. Massive matrix carburization and intergranular carbide precipitation were seen for both steels. The experimental results showed that niobium (Nb) could delay the ingress of carbon and retard the metal dusting reaction.

  20. The resistance of titanium to pitting, microbially induced corrosion and corrosion in unsaturated conditions

    Energy Technology Data Exchange (ETDEWEB)

    Shoesmith, D W; Ikeda, B M

    1997-04-01

    Titanium and its alloys (Grades-2, -12, -16) are candidate materials for Canadian nuclear waste containers on the basis of their apparent immunity to many localized corrosion processes. This simplifies markedly the effort needed to justify the use of these materials and to develop models to predict the lifetimes of containers. Here we review the pitting, microbially influenced corrosion (MIC), and corrosion under unsaturated conditions, of titanium. For all these processes, the properties of the passive oxide film are paramount in determining the metal`s resistance to corrosion. A review of these oxide properties is included and the conditions to which the metal must be exposed if localized corrosion is to occur are defined. Since these conditions cannot be achieved under Canadian waste vault conditions, it can be concluded that pitting and MIC will not occur and that corrosion under unsaturated conditions is extremely unlikely. (author) 114 refs., 1 tab., 18 figs.

  1. Close-out of open pit and waste rock piles of a uranium mine in Guangxi province of China

    International Nuclear Information System (INIS)

    Xu Lechang; Zhang Zhao; Zhang Guopu; Liu Min

    2012-01-01

    Close-out of projects of a mine in Guangxi province of China includes open pit,east and west waste rock piles, ore transfer station, industrial fields, buildings, ore transporting road, and equipment and conduits. The following remediation limits are introduced: environment penetrating radiation dose rate and 222 Rn flux of open pit and waste rock piles, 226 Ra specific activity of soil and individual dose. Remediation objective and programme are discussed in details. Remediation effects are evaluated. (authors)

  2. Bioremediation of Acidic and Metalliferous Drainage (AMD) through organic carbon amendment by municipal sewage and green waste.

    Science.gov (United States)

    McCullough, Clint D; Lund, Mark A

    2011-10-01

    Pit lakes (abandoned flooded mine pits) represent a potentially valuable water resource in hot arid regions. However, pit lake water is often characterised by low pH with high dissolved metal concentrations resulting from Acidic and Metalliferous Drainage (AMD). Addition of organic matter to pit lakes to enhance microbial sulphate reduction is a potential cost effective remediation strategy. However, cost and availability of suitable organic substrates are often limiting. Nevertheless, large quantities of sewage and green waste (organic garden waste) are often available at mine sites from nearby service towns. We treated AMD pit lake water (pH 2.4) from tropical, North Queensland, Australia, with primary-treated sewage sludge, green waste, and a mixture of sewage and green waste (1:1) in a controlled microcosm experiment (4.5 L). Treatments were assessed at two different rates of organic loading of 16:1 and 32:1 pit water:organic matter by mass. Combined green waste and sewage treatment was the optimal treatment with water pH increased to 5.5 in only 145 days with decreases of dissolved metal concentrations. Results indicated that green waste was a key component in the pH increase and concomitant heavy metal removal. Water quality remediation was primarily due to microbially-mediated sulphate reduction. The net result of this process was removal of sulphate and metal solutes to sediment mainly as monosulfides. During the treatment process NH(3) and H(2)S gases were produced, albeit at below concentrations of concern. Total coliforms were abundant in all green waste-treatments, however, faecal coliforms were absent from all treatments. This study demonstrates addition of low-grade organic materials has promise for bioremediation of acidic waters and warrants further experimental investigation into feasibility at higher scales of application such as pit lakes. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  3. Tanacetum vulgare as a bioindicator of trace-metal contamination: a study of a naturally colonized open-pit lignite mine.

    Science.gov (United States)

    Jasion, Mateusz; Samecka-Cymerman, Aleksandra; Kolon, Krzysztof; Kempers, Alexander J

    2013-10-01

    We investigated the possibility of use of Tanacetum vulgare (tansy) as an ecological indicator of metal concentration in a naturally colonized open-pit lignite mine in Bełchatów (Poland). Tanacetum vulgare is the only species growing abundantly and spontaneously in the lignite mine waste dumps. Metal concentrations in roots, stems, leaves, flowers, and soil were measured in dump sites differing in type and time of reclamation and therefore differing in pollution levels. Tanacetum vulgare appeared to be an accumulator of chromium and iron in roots, whereas highest concentrations of manganese and zinc were found in leaves. A high bioaccumulation factor for cadmium (Cd) was observed in dumps and control sites, indicating that even small amounts of Cd in the environment may result in significant uptake by the plant. The lowest concentrations of metals were found in plants from sites situated on dumps reclaimed with argillaceous limestone.

  4. The flooded pit at Aznalcollar (Seville, Spain) and its use as a dumping site for mine waste; La corta inundada de Aznalcollar y su uso como vertedero de residuos mineros (Sevilla, Espana)

    Energy Technology Data Exchange (ETDEWEB)

    Santofimia Pastor, E.; Lopez Pamo, E.; Montero Gonzalez, E.

    2011-07-01

    Since its closure in 1995 and the subsequent failure of the slurry deposit dam in 1998, the Aznalcollar pit has been used as a disposal site for diverse metal-rich materials, such as the polluted soils removed during the cleaning-up of areas along the Guadiamar river together with waste rock, pyrite sludge and ashes deriving from pyrite roasting. At present the pit is partly flooded with a highly acidic (pH 2.7) lake holding some 6 Mm{sup 3} of metal- and sulphate-rich water. Detailed research undertaken in the area during recent years has proved that the dumping of wastes and the inflow of acidic mine waters are having a dramatic effect on the quality of the water in the lake. The greatest effect upon the Aznalcollar lake water was due to the dumping of 1.4 Mm{sup 3} of pyritic wastes during 2005 and 2006. The oxidative dissolution of this mineral has resulted firstly in the total consumption of dissolved oxygen, secondly, a notable increase in electric conductivity (from 8.6 to 12 mS/cm), thirdly, considerable acidification (from pH 4.2 to 2.7) and finally, heating due to the exothermic character of pyrite oxidation. Despite the almost total lack of oxidizing agents such as O{sub 2} and Fe(III) (Fe(III)<5% Fetotal) in the pit lake, pyrite continues to oxidize, producing a concomitant increase in SO{sub 4}{sup 2}- and Fe. (Author) 32 refs.

  5. Microstructure and pitting corrosion of shielded metal arc welded high nitrogen stainless steel

    Directory of Open Access Journals (Sweden)

    Raffi Mohammed

    2015-09-01

    Full Text Available The present work is aimed at studying the microstructure and pitting corrosion behaviour of shielded metal arc welded high nitrogen steel made of Cromang-N electrode. Basis for selecting this electrode is to increase the solubility of nitrogen in weld metal due to high chromium and manganese content. Microscopic studies were carried out using optical microscopy (OM and field emission scanning electron microscopy (FESEM. Energy back scattered diffraction (EBSD method was used to determine the phase analysis, grain size and orientation image mapping. Potentio-dynamic polarization testing was carried out to study the pitting corrosion resistance in aerated 3.5% NaCl environment using a GillAC electrochemical system. The investigation results showed that the selected Cr–Mn–N type electrode resulted in a maximum reduction in delta-ferrite and improvement in pitting corrosion resistance of the weld zone was attributed to the coarse austenite grains owing to the reduction in active sites of the austenite/delta ferrite interface and the decrease in galvanic interaction between austenite and delta-ferrite.

  6. Management of Pit 9 - highlights of accomplishments and lessons learned to date

    International Nuclear Information System (INIS)

    Schwartz, F.G.

    1995-01-01

    The Pit 9 project is a U.S. Department of Energy prototype full scale demonstration to retrieve and treat buried mixed transuranic waste. The project is being managed by the DOE-Idaho Environmental Restoration Program, in conjunction with the Environmental Protection Agency Region 10 and the state of Idaho, under the Idaho National Engineering Laboratory Federal Facility Agreement and Consent Order. Pit 9 is located in the northeast corner of the Subsurface Disposal Area (SDA) of the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering Laboratory (INEL). The Pit 9 project was conceived out of the need to determine capabilities to cost effectively retrieve and treat buried radioactive and radioactive mixed waste, and obtain characterization and contaminant migration data for buried waste at the INEL. Waste was disposed in Pit 9 from November 1967 to June 1969. Pit 9, at about 380 feet by 125 feet, represents approximately one acre of surface area of the 88 acre SDA. The pit contains approximately 350,000 ft 3 of soil beneath and between the buried waste and about 250,000 ft 3 of overburden soil. The average depth of the pit from soil surface to bedrock is approximately 17.5 feet. Approximately 110,000 ft 3 of transuranic (TRU) contaminated mixed wastes from Rocky Flats and approximately 40,000 ft 3 of low level and mixed wastes from the INEL were buried in Pit 9 during this period. Pit 9 is estimated to contain over 30,000 gallons of organics (over 30% of the total organic inventory in the SDA) and approximately 66 pounds of TRU radionuclides (between 3% and 4% of the total TRU inventory in the SDA). Pit 9 was selected as a demonstration site because it was one of the last disposal pits at the INEL to receive Rocky Flats waste, disposal records are better for Pit 9 than for disposal pits and trenches from earlier points in time, and the wastes in Pit 9 are representative of the wastes disposed in the SDA

  7. The resistance of titanium to pitting, microbially induced corrosion and corrosion in unsaturated conditions

    International Nuclear Information System (INIS)

    Shoesmith, D.W.; Ikeda, B.M.

    1997-04-01

    Titanium and its alloys (Grades-2, -12, -16) are candidate materials for Canadian nuclear waste containers on the basis of their apparent immunity to many localized corrosion processes. This simplifies markedly the effort needed to justify the use of these materials and to develop models to predict the lifetimes of containers. Here we review the pitting, microbially influenced corrosion (MIC), and corrosion under unsaturated conditions, of titanium. For all these processes, the properties of the passive oxide film are paramount in determining the metal's resistance to corrosion. A review of these oxide properties is included and the conditions to which the metal must be exposed if localized corrosion is to occur are defined. Since these conditions cannot be achieved under Canadian waste vault conditions, it can be concluded that pitting and MIC will not occur and that corrosion under unsaturated conditions is extremely unlikely. (author)

  8. Closure Report for Corrective Action Unit 357: Mud Pits and Waste Dump, Nevada Test Site, Nevada, Rev. No.: 0

    Energy Technology Data Exchange (ETDEWEB)

    Laura A. Pastor

    2005-04-01

    This Closure Report (CR) presents information supporting closure of Corrective Action Unit (CAU) 357: Mud Pits and Waste Dump, Nevada Test Site (NTS), Nevada. The CR complies with the requirements of the Federal Facility Agreement and Consent Order (FFACO) that was agreed to by the State of Nevada, U.S. Department of Energy (DOE), and the U.S. Department of Defense (FFACO, 1996). Corrective Action Unit 357 is comprised of 14 Corrective Action Sites (CASs) located in Areas 1, 4, 7, 8, 10, and 25 of the NTS (Figure 1-1). The NTS is located approximately 65 miles (mi) northwest of Las Vegas, Nevada. Corrective Action Unit 357 consists of 11 CASs that are mud pits located in Areas 7, 8, and 10. The mud pits were associated with drilling activities conducted on the NTS in support of the underground nuclear weapons testing. The remaining three CASs are boxes and pipes associated with Building 1-31.2el, lead bricks, and a waste dump. These CAS are located in Areas 1, 4, and 25, respectively. The following CASs are shown on Figure 1-1: CAS 07-09-02, Mud Pit; CAS 07-09-03, Mud Pit; CAS 07-09-04, Mud Pit; CAS 07-09-05, Mud Pit; CAS 08-09-01, Mud Pit; CAS 08-09-02, Mud Pit; CAS 08-09-03, Mud Pit; CAS 10-09-02, Mud Pit; CAS 10-09-04, Mud Pit; CAS 10-09-05, Mud Pit; CAS 10-09-06, Mud Pit, Stains, Material; CAS 01-99-01, Boxes, Pipes; CAS 04-26-03, Lead Bricks; and CAS 25-15-01, Waste Dump. The purpose of the corrective action activities was to obtain analytical data that supports the closure of CAU 357. Environmental samples were collected during the investigation to determine whether contaminants exist and if detected, their extent. The investigation and sampling strategy was designed to target locations and media most likely to be contaminated (biased sampling). A general site conceptual model was developed for each CAS to support and guide the investigation as outlined in the Streamlined Approach for Environmental Restoration (SAFER) Plan (NNSA/NSO, 2003b). This CR

  9. Effects of rare earth metals addition on the resistance to pitting corrosion of super duplex stainless steel - Part 1

    International Nuclear Information System (INIS)

    Kim, Soon-Tae; Jeon, Soon-Hyeok; Lee, In-Sung; Park, Yong-Soo

    2010-01-01

    To elucidate the effects of rare earth metals addition on the resistance to pitting corrosion of super duplex stainless steel, a metallographic examination, potentiodynamic and potentiostatic polarization tests, a SEM-EDS and a SAM analysis of inclusion, austenite phase and ferrite phase were conducted. The addition of rare earth metals to the base alloy led to the formation of (Mn, Cr, Si, Al, Ce) oxides and (Mn, Cr, Si, Ce) oxides, which improved the resistance to pitting corrosion and caused a decrease in the preferential interface areas for the initiation of the pitting corrosion.

  10. Evaluation on construction quality of pit filler material of cavern type radioactive waste disposal facility

    International Nuclear Information System (INIS)

    Takechi, Shin-ichi; Yokozeki, Kosuke; Shimbo, Hiroshi; Terada, Kenji; Akiyama, Yoshihiro; Yada, Tsutomu; Tsuji, Yukikazu

    2014-01-01

    The pit filler material of the underground cavern-type radioactive waste disposal facility, which is poured directly around the radioactive waste packages where high temperature environment is assumed by their decay heat, is concerned to be adversely affected on the filling behavior and its hardened properties. There also are specific issues that required quality of construction must be achieved by unmanned construction with remote operation, because the pit filler construction shall be done under radiation environment. In this paper, the mix proportion of filler material is deliberated with filling experiments simulating high temperature environment, and also the effect of temperature on hardened properties are confirmed with high temperature curing test. Subsequently, the feasibility of unmanned construction method of filler material by pumping, and by movable bucket, are comparatively discussed through a real size demonstration. (author)

  11. INEL cold test pit demonstration of improvements in information derived from non-intrusive geophysical methods over buried waste sites

    International Nuclear Information System (INIS)

    1994-01-01

    Under contract between US DOE Idaho National Engineering Laboratory (INEL) and the Blackhawk Geosciences Division of Coleman Research Corporation (BGD-CRC), geophysical investigations were conducted to improve the detection of buried wastes. Over the Cold Test Pit (CTP) at INEL, data were acquired with multiple sensors on a dense grid. Over the CTP the interpretations inferred from geophysical data are compared with the known placement of various waste forms in the pit. The geophysical sensors employed were magnetics, frequency and time domain electromagnetics, and ground penetrating radar. Also, because of the high data density acquired, filtering and other data processing and imaging techniques were tested. After completion and analysis of the survey and interpretation over the CTP, the second phase of investigation consisted of testing geophysical methods over the Idaho Chemical Processing Plant (ICPP). The sections of the ICPP surveyed are underlain by a complex network of buried utility lines of different dimensions and composition, and with placement at various depths up to 13 ft. Further complications included many metallic objects at the surface, such as buildings, reinforced concrete pads, and debris. Although the multiple geophysical sensor approach mapped many buried utilities, they mapped far from all utilities shown on the facility drawings. This report consists of data collected from these geophysical surveys over the ICPP

  12. MINE WASTE TECHNOLOGY PROGRAM PREVENTION OF ACID MINE DRAINAGE GENERATION FROM OPEN-PIT HIGHWALLS

    Science.gov (United States)

    This document summarizes the results of Mine Waste Technology Program Activity III, Project 26, Prevention of Acid Mine Drainage Generation from Open-Pit Highwalls. The intent of this project was to obtain performance data on the ability of four technologies to prevent the gener...

  13. Ecological risk of reprocessing of uranium wastes of the Gafurov-city's tailing pit

    International Nuclear Information System (INIS)

    Hakimov; Nazarov, H.M.; Mirsaidov, U.M.

    2005-01-01

    The authors set as their purpose the investigation of ecological risk of reprocessing of uranium wastes of the Gafurov-city's tailing pit. Having carried out their investigations, the authors came to the conclusion that the effect of radon gas during reprocessing to workers and specialists is minimal if they follow all the required safety rules

  14. Plasma methods for metals recovery from metal-containing waste.

    Science.gov (United States)

    Changming, Du; Chao, Shang; Gong, Xiangjie; Ting, Wang; Xiange, Wei

    2018-04-27

    Metal-containing waste, a kind of new wastes, has a great potential for recycling and is also difficult to deal with. Many countries pay more and more attention to develop the metal recovery process and equipment of this kind of waste as raw material, so as to solve the environmental pollution and comprehensively utilize the discarded metal resources. Plasma processing is an efficient and environmentally friendly way for metal-containing waste. This review mainly discuss various metal-containing waste types, such as printed circuit boards (PCBs), red mud, galvanic sludge, Zircon, aluminium dross and incinerated ash, and the corresponding plasma methods, which include DC extended transferred arc plasma reactor, DC non-transferred arc plasma torch, RF thermal plasma reactor and argon and argon-hydrogen plasma jets. In addition, the plasma arc melting technology has a better purification effect on the extraction of useful metals from metal-containing wastes, a great capacity of volume reduction of waste materials, and a low leaching toxicity of solid slag, which can also be used to deal with all kinds of metal waste materials, having a wide range of applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. IP and resistivity survey at the INEL cold test pit

    International Nuclear Information System (INIS)

    Frangos, W.

    1997-01-01

    Induced polarization (IP) is a technique for detection of diffuse occurrences of metallic material. The Idaho National Laboratory (INEL) Cold Test Pit (CTP) has been carefully constructed to simulate stored hazardous waste occurrences. IP and resistivity surveys of the CTP show a very strong IP response and a modest resistivity response associated with the simulated waste. Several false positive resistivity anomalies are noted. 2-D inversion of the data accurately determine the lateral limits of the waste zone. The depth of burial indicated is deeper than reported by the construction engineers. Limited depth extent is recognized, in distinction to results from other, resistivity-based, methods, but it also appears too deep. IP holds promise as a method for locating buried waste

  16. Mobile unit for enclosing hot solid waste in a metal matrix

    International Nuclear Information System (INIS)

    Sobolev, I.A.; Arustamov, A.E.; Shiryaev, V.V.; Ozhovan, M.I.; Semenov, K.N.; Kachalov, M.B.

    1993-01-01

    After termination of their service life, the sources of ionizing radiation are transported to special burial points of radioactive waste in pitlike repositories near the surface. The repositories are cylindrical 200-litter cavities of stainless steel and are situated at a depth of 6 m in a concrete pit. The pit is concrete enveloped. The spent sources enter the cavity via a curve loading a tube. Water was observed in repositories of this type; in a powerful radiation field (with up to 10 4 R/sec), water accelerates the corrosion of the shells of the sources and liberates radiolytic hydrogen. In order to obtain reliable isolation of the sources, a new technique of enclosing the sources in a metal matrix of low-melting metals (layer-by-layer and directly in the repository) has been used since 1986 in the Moscow Scientific Planning Department 'Radon'. This makes it possible to preserve the traditional burial of spent sources and, in addition, to use the radiation shielding of the repository proper. Investigations have shown that this technique is very reliable: There are no radiolytic gases, the radiation field and the temperature field in the repository are substantially reduced, and therefore the volume of the repositories is increased by a factor of 5-6. The total activity of the spent sources enclosed in a metal matrix in accordance with this technique amounted to about 500,000 Ci in test units and semi-industrial units

  17. Mercerized mesoporous date pit activated carbon-A novel adsorbent to sequester potentially toxic divalent heavy metals from water.

    Science.gov (United States)

    Aldawsari, Abdullah; Khan, Moonis Ali; Hameed, B H; Alqadami, Ayoub Abdullah; Siddiqui, Masoom Raza; Alothman, Zeid Abdullah; Ahmed, A Yacine Badjah Hadj

    2017-01-01

    A substantive approach converting waste date pits to mercerized mesoporous date pit activated carbon (DPAC) and utilizing it in the removal of Cd(II), Cu(II), Pb(II), and Zn(II) was reported. In general, rapid heavy metals adsorption kinetics for Co range: 25-100 mg/L was observed, accomplishing 77-97% adsorption within 15 min, finally, attaining equilibrium in 360 min. Linear and non-linear isotherm studies revealed Langmuir model applicability for Cd(II) and Pb(II) adsorption, while Freundlich model was fitted to Zn(II) and Cu(II) adsorption. Maximum monolayer adsorption capacities (qm) for Cd(II), Pb(II), Cu(II), and Zn(II) obtained by non-linear isotherm model at 298 K were 212.1, 133.5, 194.4, and 111 mg/g, respectively. Kinetics modeling parameters showed the applicability of pseudo-second-order model. The activation energy (Ea) magnitude revealed physical nature of adsorption. Maximum elution of Cu(II) (81.6%), Zn(II) (70.1%), Pb(II) (96%), and Cd(II) (78.2%) were observed with 0.1 M HCl. Thermogravimetric analysis of DPAC showed a total weight loss (in two-stages) of 28.3%. Infra-red spectral analysis showed the presence of carboxyl and hydroxyl groups over DPAC surface. The peaks at 820, 825, 845 and 885 cm-1 attributed to Zn-O, Pb-O, Cd-O, and Cu-O appeared on heavy metals saturated DPAC, confirmed their binding on DPAC during the adsorption.

  18. Literature survey on metal waste form for metallic waste from electrorefiners for the electrometallurgical treatment of spent metallic fuels

    International Nuclear Information System (INIS)

    Nishimura, Tomohiro

    2003-01-01

    This report summarizes the recent results of the metal waste form development activities at the Argonne National Laboratory in the USA for high-level radioactive metallic waste (stainless-steel (SS) cladding hulls, zirconium (Zr), noble-metal fission products (NMFPs), etc.) from electrorefiners for the electrometallurgical treatment of spent metallic fuels. Their main results are as follows: (1) SS- 15 wt.% Zr- ∼4 wt.% NMFPs alloy was selected as the metal waste form, (2) metallurgical data, properties, long-term corrosion data, etc. of the alloy have been collected, (3) 10-kg ingots have been produced in hot tests and a 60-kg production machine is under development. The following research should be made to show the feasibility of the metal waste form in Japan: (1) degradation assessment of the metal waste form in Japanese geological repository environments, and (2) clarification of the maximum allowable contents of NMFPs. (author)

  19. Pit Viper strikes at the Hanford site. Pit maintenance using robotics at the Hanford Tank Farms

    International Nuclear Information System (INIS)

    Roeder-Smith, Lynne

    2002-01-01

    The Pit Viper--a remote operations waste retrieval system--was developed to replace manual operations in the valve pits of waste storage tanks at the Hanford Site. The system consists of a typical industrial backhoe fitted with a robotic manipulator arm and is operated remotely from a control trailer located outside of the tank farm. Cameras mounted to the arm and within the containment tent allow the operator to view the entire pit area and operate the system using a joystick. The arm's gripper can grasp a variety of tools that allow personnel to perform cleaning, debris removal, and concrete repair tasks--a more efficient and less dose-intensive process than the previous 'long-pole' method. The project team overcame a variety of obstacles during development and testing of the Pit Viper system, and deployment occurred in Hanford Tank C-104 in December 2001

  20. Engineering evaluation/cost analysis: Waste Pit Area storm water runoff control, Feed Materials Production Center, Fernald, Ohio

    International Nuclear Information System (INIS)

    1990-08-01

    This report evaluates remedial action alternatives at the Feed Materials production Center in response to the need to contain contaminated storm water runoff. The storm water is being contaminated as it falls over a radioactive/chemical waste pit which contains uranium contaminated wastes. Alternatives considered include no action, surface capping, surface capping with lateral drainage, runoff collection and treatment, and source removal

  1. Pitting corrosion of copper. An equilibrium - mass transport study

    Energy Technology Data Exchange (ETDEWEB)

    Taxen, C

    1996-11-01

    A mathematical model for the propagation of corrosion pits on copper is described. The model is used to predict the potentials below which copper is immune to pitting. The criteria used for immunity against pitting is that the volume of the cuprous oxide formed at the site of the metal oxidation at the bottom of a corrosion pit must be smaller than the volume of the oxidised metal. Equal volumes would give a complete coverage of the metal in a pit by adherent cuprous oxide and propagation would not be possible. For potentials where copper is not immune to pitting an estimate of the maximum growth rate is given. The model uses equilibrium data and diffusion coefficients and calculates the stationary concentration profiles from the bulk water outside a corrosion pit to the site of the metal dissolution at the bottom a corrosion pit. Precipitation of oxides as well as of basic salts of copper is considered. A total of 26 aqueous species are considered in waters with compositions ranging from those of tap waters to that of sea water. Calculations are made for the temperatures 25 deg C and 75 deg C. 38 refs, 60 figs, 17 tabs

  2. Retrieval of buried waste using conventional equipment

    International Nuclear Information System (INIS)

    Valentich, D.J.

    1994-01-01

    A field test was conducted to determine the effectiveness of using conventional type construction equipment for the retrieval of buried transuranic (TRU) waste. A cold (nonhazardous and nonradioactive test pit 841 m 3 in volume) was constructed with boxes and drums filled with simulated waste materials, such as metal, plastic, wood, concrete, and sludge. Large objects, including truck beds, vessels, vaults, pipes, and beams were also placed in the pit. These materials were intended to simulate the type of waste found in existing TRU buried waste pits and trenches. A series of commercially available equipment items, such as excavators and tracked loaders outfitted with different end effectors, were used to remove the simulated waste. Work was performed from both the abovegrade and belowgrade positions. During the demonstration, a number of observations, measurements, and analyses were performed to determine which equipment was the most effective in removing the waste. The retrieval rates for the various excavation techniques were recorded. The inherent dust control capabilities of the excavation methods used were also observed

  3. Defining a metal-based waste form for IFR pyroprocessing wastes

    International Nuclear Information System (INIS)

    McDeavitt, S.M.; Park, J.Y.; Ackerman, J.P.

    1994-01-01

    Pyrochemical electrorefining to recover actinides from metal nuclear fuel is a key element of the Integral Fast Reactor (IFR) fuel cycle. The process separates the radioactive fission products from the long-lived actinides in a molten LiCl-KCl salt, and it generates a lower waste volume with significantly less long-term toxicity as compared to spent nuclear fuel. The process waste forms include a mineral-based waste form that will contain fission products removed from an electrolyte salt and a metal-based waste form that will contain metallic fission products and the fuel cladding and process materials. Two concepts for the metal-based waste form are being investigated: (1) encapsulating the metal constituents in a Cu-Al alloy and (2) alloying the metal constituents into a uniform stainless steel-based waste form. Results are given from our recent studies of these two concepts

  4. Silica exposure to excavation workers during the excavation of a low level radiological waste pit and tritium disposal shafts

    International Nuclear Information System (INIS)

    Wilson, K.M.

    1995-01-01

    This study evaluated the task-length average (TLA) respirable dust and respirable silica airborne concentrations to which construction workers excavating volcanic tuff at Los Alamos National Laboratory (LANL) were exposed. These workers were excavating a low level radiological waste disposal pit of final dimensions 720 feet long, 132 feet wide and 60 feet deep. The objectives of this study were as follows: (1) evaluate exposures; (2) determine if the type of machinery used affects the respirable dust concentration in the breathing zone of the worker; (3) evaluate the efficacy of wetting the pit to reduce the respirable dust exposure; and (4) determine if exposure increases with increasing depth of pit due to the walls of the pit blocking the cross wind ventilation

  5. Effects of heat input on pitting corrosion in super duplex stainless steel weld metals

    Science.gov (United States)

    Shin, Yong taek; Shin, Hak soo; Lee, Hae woo

    2012-12-01

    Due to the difference in reheating effects depending on the heat input of subsequent weld passes, the microstructure of the weld metal varies between acicular type austenite and a mixture of polygonal type and grain boundary mixed austenite. These microstructural changes may affect the corrosion properties of duplex stainless steel welds. This result indicates that the pitting resistance of the weld can be strongly influenced by the morphology of the secondary austenite phase. In particular, the ferrite phase adjacent to the acicular type austenite phase shows a lower Pitting Resistance Equivalent (PRE) value of 25.3, due to its lower chromium and molybdenum contents, whereas the secondary austenite phase maintains a higher PRE value of more than 38. Therefore, it can be inferred that the pitting corrosion is mainly due to the formation of ferrite phase with a much lower PRE value.

  6. The potential of two Salix genotypes for radionuclide/heavy metal accumulation. A case study of Rovinari ash pit (Gorj District, Romania)

    Science.gov (United States)

    Hernea, Cornelia; Neţoiu, Constantin; Corneanu, Gabriel; Crăciun, Constantin; Corneanu, Mihaela; Cojocaru, Luminiţa; Rovena Lăcătuşu, Anca; Popescu, Ion

    2014-05-01

    Thermo Electric Power Plants (TEPP) produce a high amount of ash, that contains heavy metals and radionuclides. Ash is usually stored in ash-pits, in mixture with water and contains U235, Th 234 and their decay products, that are released from the coal matrix, during combustion, as well as heavy metals. Warm weather dried the ash and it can be spread by the wind in surrounded area. This paper presents the results of an experiment with two Salix genotypes, cultivated on an old closed ash-pit, nearby the Rovinari TEPP, in the middle Jiu valley (Gorj District, Romania), in order to evaluate its tolerance to heavy metals and radionuclides. Ash analysis revealed the presence of natural radionuclides, beloging from ash and coal dust, as well as of Cs 137, of Chernobil provenance. Radionuclides content over the normal limits for Romania were registered for Th 234, Pb210, U235 and Ra226. The heavy metals level in ash was over the normal limits, but under the alerts limits. In order to establish the woody plants tolerance to heavy metals and radionuclides, it is important to study the seedlings behavior. In this respect Salix alba and Salix viminalis whips and cuttings culture have been establish on Rovinari ash-pit. The observations made on survival and growth rate pointed out the superiority of Salix viminalis behaviour. After a period of three years Salix viminalis registered a 96% survival rate, while in Salix alba annual decreases, reaching to 14%. These results are supported by the radionuclides content in leaves and by the electron microscopy studies. In Salix alba the leaves parenchimatic cells present a low sinthesis activity. The exogenous particles are accumulated in parenchima cells vacuola, the chloroplasts are usually agranal, with few starch grains and mitocondria presents slightly dillated crista. The ultrastructural features of the mature leaf cells, evidenced the natural adaptation of Salix viminalins for development in an environment with a big amount of

  7. A phenomenological approach to simulating the evolution of radioactive-waste container damage due to pitting corrosion

    International Nuclear Information System (INIS)

    Henshall, G.A.

    1995-01-01

    The damage to high-level radioactive-waste containers by pitting corrosion is an important design and performance assessment consideration. It is desirable to calculate the evolution of the pit depth distribution, not just the time required for initial penetration of the containers, so that the area available for advective of diffusive release of radionuclides through the container can be estimated. A phenomenological approach for computing the time evolution of these distributions is presented which combines elements of the deterministic and stochastic aspects of pit growth. The consistency of this approach with the mechanisms believed to control the evolution of the pit depth distribution is discussed. Qualitative comparisons of preliminary model predictions with a variety of experimental data from the literature are shown to be generally favorable. The sensitivity of the simulated distributions to changes in the input parameters is discussed. Finally, the results of the current model are compared to those of existing approaches based on extreme-value statistics, particularly regarding the extrapolation of laboratory data to large exposed surface areas

  8. Trace metal depositional patterns from an open pit mining activity as revealed by archived avian gizzard contents.

    Science.gov (United States)

    Bendell, L I

    2011-02-15

    Archived samples of blue grouse (Dendragapus obscurus) gizzard contents, inclusive of grit, collected yearly between 1959 and 1970 were analyzed for cadmium, lead, zinc, and copper content. Approximately halfway through the 12-year sampling period, an open-pit copper mine began activities, then ceased operations 2 years later. Thus the archived samples provided a unique opportunity to determine if avian gizzard contents, inclusive of grit, could reveal patterns in the anthropogenic deposition of trace metals associated with mining activities. Gizzard concentrations of cadmium and copper strongly coincided with the onset of opening and the closing of the pit mining activity. Gizzard zinc and lead demonstrated significant among year variation; however, maximum concentrations did not correlate to mining activity. The archived gizzard contents did provide a useful tool for documenting trends in metal depositional patterns related to an anthropogenic activity. Further, blue grouse ingesting grit particles during the time of active mining activity would have been exposed to toxicologically significant levels of cadmium. Gizzard lead concentrations were also of toxicological significance but not related to mining activity. This type of "pulse" toxic metal exposure as a consequence of open-pit mining activity would not necessarily have been revealed through a "snap-shot" of soil, plant or avian tissue trace metal analysis post-mining activity. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Full-scale retrieval of simulated buried transuranic waste

    International Nuclear Information System (INIS)

    Valentich, D.J.

    1993-09-01

    This report describes the results of a field test conducted to determine the effectiveness of using conventional type construction equipment for the retrieval of buried transuranic (TRU) waste. A cold (nonhazardous and nonradioactive) test pit (1,100 yd 3 volume) was constructed with boxes and drums filled with simulated waste materials, such as metal, plastic, wood, concrete, and sludge. Large objects, including truck beds, tanks, vaults, pipes, and beams, were also placed in the pit. These materials were intended to simulate the type of wastes found in TRU buried waste pits and trenches. A series of commercially available equipment items, such as excavators and tracked loaders outfitted with different end effectors, were used to remove the simulated waste. Work was performed from both the abovegrade and belowgrade positions. During the demonstration, a number of observations, measurements, and analyses were performed to determine which equipment was the most effective in removing the waste. The retrieval rates for the various excavation techniques were recorded. The inherent dust control capabilities of the excavation methods used were observed. The feasibility of teleoperating reading equipment was also addressed

  10. Corrective action investigation plan: Area 2 Photo Skid 16 Wastewater Pit, Corrective Action Unit 332. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    This Corrective Action Investigation Plan (CAIP) contains a detailed description and plan for an environmental investigation of the Area 2 Photo Skid 16 Wastewater Pit. The site is located in Area 2 of the Nevada Test Site. The Photo Skid Wastewater Pit was used for disposal of photochemical process waste, and there is a concern that such disposal may have released photochemicals and metals to the soil beneath the pit and adjacent to it. The purpose of this investigation is to identify the presence and nature of contamination present in and adjacent to the wastewater pit and to determine the appropriate course of environmental response action for the site. The potential courses of action for the site are clean closure through remediation, closure in place (with or without remediation), or no further action.

  11. Valorization of waste Date pits biomass for biodiesel production in presence of green carbon catalyst

    International Nuclear Information System (INIS)

    Abu-Jrai, Ahmad M.; Jamil, Farrukh; Al-Muhtaseb, Ala'a H.; Baawain, Mahad; Al-Haj, Lamya; Al-Hinai, Mohab; Al-Abri, Mohammed; Rafiq, Sikander

    2017-01-01

    Highlights: • Waste Date pits were utilized to produce green catalyst for biodiesel production. • The optimized yield of biodiesel was 91.6% at 65 °C and 9:1 methanol to oil ratio. • Catalyst activity decreases very less upon reusing it up to three runs. • Produced biodiesel possess competent fuel properties as per ASTM and EN standards. - Abstract: In this study, an efficient utilization of waste Date pits biomass for synthesizing green carbon catalyst as well as production of biodiesel were investigated. The green carbon catalyst was modified by KOH and characterized by XRD, SEM, EDX, TEM and BET. Taguchi method in Response Surface Methodology (RSM) was applied to study the effect of several process parameters such as reaction temperature, time, catalysts type and methanol to oil ratio, on the yield of the produced biodiesel. The optimized yield obtained was 91.6% when the process temperature was 65 °C, with catalyst type C3 (6 wt% KOH on carbon) within 1 h and with 9:1 methanol to oil ratio. The produced biodiesel was completely characterized in order to verify its quality, compared with the international standards. Fuel properties of the produced biodiesel were found to be a cetane number 60.31, density 881 kg/m"3, viscosity 4.24 mm"2/s, cloud point 3.9 °C, cold filter plugging point −0.62 °C, pour point −1.4 °C and flash point 141 °C, which lies within the limits specified by the international standards of ASTM and EN. Waste Date pits biomass can be a promising platform for the production of green carbon catalysts as well as biodiesel production.

  12. Single pit propagation on austenitic stainless steel

    International Nuclear Information System (INIS)

    Heurtault, Stephane

    2016-01-01

    The electrochemical characterization of metastable events such as pitting corrosion of stainless steel in chloride electrolyte remains complex because many individual processes may occur simultaneously on the alloy surface. To overcome these difficulties, an experimental setup, the flow micro-device, has been developed to achieve the initiation of a single pit and to propagate the single pit in three dimensions. In this work, we take advantage of such a device in order to revisit the pitting process on a 316L stainless steel in a chloride - sulphate bulk. In a first step, the time evolution of the pit geometry (depth, radius) and the chemical evolution of the pit solution investigated using in situ Raman spectroscopy have shown that the pit depth propagation depends on the formation of a metal chloride and sulphate gel in the pit solution, and is controlled by the metallic cations diffusion from the pit bottom to the pit mouth. The pit radius growth is defined by the initial surface de-passivation, by the presence of a pit cover and by the gel development in the solution. all of these phenomena are function of applied potential and chemical composition of the solution. In a last step, it was demonstrated that a critical chloride concentration is needed in order to maintain the pit propagation. This critical concentration slightly increases with the pit depth. From statistical analysis performed on identical experiments, a zone diagram showing the pit stability as a function of the chloride concentration and the pit dimensions was built. (author) [fr

  13. Waste Management: DOD Has Generally Addressed Legislative Requirements on the Use of Burn Pits but Needs to Fully Assess Health Effects

    Science.gov (United States)

    2016-09-01

    such as tires , treated wood, and batteries) in burn pits during contingency operations. GAO found that DOD’s report fully addressed four of the seven...regulations prohibiting the disposal of covered waste (including certain types of hazardous waste, medical waste, and items such as tires , treated...required contractors to segregate non-hazardous, hazardous, and recyclable materials; establish recycling systems; and maintain all solid waste operations

  14. Effects of sulfur addition on pitting corrosion and machinability behavior of super duplex stainless steel containing rare earth metals: Part 2

    International Nuclear Information System (INIS)

    Jeon, Soon-Hyeok; Kim, Soon-Tae; Lee, In-Sung; Park, Yong-Soo

    2010-01-01

    Research highlights: → The mechanisms on the effects of rare earth metals (REM) and sulfur (S) additions on the initiation and propagation of pitting corrosion and machinabillity of a super duplex stainless steel (SDSS) were elucidated → It was found that, in consideration of the ratio of lifetime (the resistance to pitting corrosion) to cost (machining and raw material), a costly austenitic stainless steel with high Ni , medium Mo and low N can be replaced by the high S and REM added SDSS with 7 wt.% Ni-4 wt% Mo-0.3 wt.% N → The resistance to pitting corrosion of the tested super duplex stainless steel was affected by the type of inclusions, the preferential interface areas between inclusions and the substrate, and the PREN difference between the γ-phase and the α-phase for the initiation and propagation of the pitting corrosion. - Abstract: To elucidate the effects of sulfur addition on pitting corrosion and machinability behavior of alloys containing rare earth metals, a potentiostatic polarization test, a critical pitting temperature test, a SEM-EDS analysis of inclusions, and a tool life test were conducted. As sulfur content increased, the resistance to pitting corrosion decreased due to the formation of numerous manganese sulfides deteriorating the corrosion resistance and an increase in the preferential interface areas for the initiation of the pitting corrosion. With an increase in sulfur content, the tool life increased due to the lubricating films of manganese sulfides adhering to tool surface.

  15. Nuclear fuel cycle waste recycling technology deverlopment - Radioactive metal waste recycling technology development

    International Nuclear Information System (INIS)

    Oh, Won Zin; Moon, Jei Kwon; Jung, Chong Hun; Park, Sang Yoon

    1998-08-01

    With relation to recycling of the radioactive metal wastes which are generated during operation and decommissioning of nuclear facilities, the following were described in this report. 1. Analysis of the state of the art on the radioactive metal waste recycling technologies. 2. Economical assessment on the radioactive metal waste recycling. 3. Process development for radioactive metal waste recycling, A. Decontamination technologies for radioactive metal waste recycling. B. Decontamination waste treatment technologies, C. Residual radioactivity evaluation technologies. (author). 238 refs., 60 tabs., 79 figs

  16. Interim Action Proposed Plan for the Chemicals, Metals, and Pesticides (CMP) Pits Operable Unit; FINAL

    International Nuclear Information System (INIS)

    Bradley, J.

    2002-01-01

    The purpose of this Interim Action Proposed Plan (IAPP) is to describe the preferred interim remedial action for addressing the Chemicals, Metals, and Pesticides (CMP) Pits Operable Unit and to provide an opportunity for public input into the remedial action selection process

  17. Design-only conceptual design report for pit disassembly and conversion facility. Rev 0

    International Nuclear Information System (INIS)

    Zygmunt, S.; Christensen, L.; Richardson, C.

    1997-01-01

    This design-only conceptual design report (DOCDR) was prepared to support a funding request by the Department of Energy (DOE)-Office of Fissile Material Disposition (OFMD) for engineering design of the Pit Disassembly and Conversion Facility (PDCF) Project No. 99-D-141. The PDCF will be used to disassemble the nation's inventory of surplus nuclear weapons pits and convert the plutonium recovered from those pits into a form suitable for storage, international inspection, and final disposition. The PDCF is a complex consisting of a hardened building that will contain the plutonium processes in a safe and secure manner, and conventional buildings and structures that will house support personnel, systems, and equipment. The PDCF uses the Advanced Recovery and Integrated Extraction System (ARIES), a low waste, modular pyroprocessing system to convert pits to plutonium oxide. The PDCF project consists of engineering and design, and construction of the buildings and structures, and engineering and design, procurement, installation, testing and start-up of equipment to disassemble pits and convert plutonium in pits to oxide form. The facility is planned to operate for 10 years, averaging 3.5 metric tons (3.86 tons) of plutonium metal per year. On conclusion of operations, the PDCF will be decontaminated and decommissioned

  18. Design-only conceptual design report for pit disassembly and conversion facility. Rev 0

    Energy Technology Data Exchange (ETDEWEB)

    Zygmunt, S.; Christensen, L.; Richardson, C.

    1997-12-12

    This design-only conceptual design report (DOCDR) was prepared to support a funding request by the Department of Energy (DOE)-Office of Fissile Material Disposition (OFMD) for engineering design of the Pit Disassembly and Conversion Facility (PDCF) Project No. 99-D-141. The PDCF will be used to disassemble the nation`s inventory of surplus nuclear weapons pits and convert the plutonium recovered from those pits into a form suitable for storage, international inspection, and final disposition. The PDCF is a complex consisting of a hardened building that will contain the plutonium processes in a safe and secure manner, and conventional buildings and structures that will house support personnel, systems, and equipment. The PDCF uses the Advanced Recovery and Integrated Extraction System (ARIES), a low waste, modular pyroprocessing system to convert pits to plutonium oxide. The PDCF project consists of engineering and design, and construction of the buildings and structures, and engineering and design, procurement, installation, testing and start-up of equipment to disassemble pits and convert plutonium in pits to oxide form. The facility is planned to operate for 10 years, averaging 3.5 metric tons (3.86 tons) of plutonium metal per year. On conclusion of operations, the PDCF will be decontaminated and decommissioned.

  19. Sustainable Environmental Protection Using Modified Pit-Latrines

    NARCIS (Netherlands)

    Chaggu, E.J.

    2004-01-01

    Pit-latrines are on-site excreta disposal facilities widely used as anaerobic accumulation system for stabilizing human wastes like excreta, both in rural and urban settlements of developing countries. Flooding of pit-latrines is often a common phenomenon, especially in situations of high water

  20. Special Analysis: Disposal Plan for Pit 38 at Technical Area 54, Area G

    Energy Technology Data Exchange (ETDEWEB)

    French, Sean B. [Los Alamos National Laboratory; Shuman, Rob [URS Coporation

    2012-06-26

    been made to utilize the remaining disposal capacity within MDA G to the greatest extent possible. One approach for doing this has been to dispose of low-activity waste from cleanup operations at LANL in the headspace of selected disposal pits. Waste acceptance criteria (WAC) for the material placed in the headspace of pits 15, 37, and 38 have been developed (LANL, 2010) and the impacts of placing waste in the headspace of these units has been evaluated (LANL, 2012a). The efforts to maximize disposal efficiency have taken on renewed importance because of the disposal demands placed on MDA G by the large volumes of waste that are being generated at LANL by cleanup efforts. For example, large quantities of waste were recently generated by the retrieval of waste formerly disposed of at TA-21, MDA B. A portion of this material has been disposed of in the headspace of pit 38 in compliance with the WAC developed for that disposal strategy; a large amount of waste has also been sent to off-site facilities for disposal. Nevertheless, large quantities of MDA B waste remain that require disposal. An extension of pit 38 was proposed to provide the disposal capacity that will be needed to dispose of institutional waste and MDA B waste through 2013. A special analysis was prepared to evaluate the impacts of the pit extension (LANL, 2012b). The analysis concluded that the disposal unit could be extended with modest increases in the exposures projected for the Area G performance assessment and composite analysis, as long as limits were placed on the radionuclide concentrations in the waste that is placed in the headspace of the pit. Based, in part, on the results of the special analysis, the extension of pit 38 was approved and excavation of the additional disposal capacity was started in May 2012. The special analysis presented here uses performance modeling to identify a disposal plan for the placement of waste in pit 38. The modeling uses a refined design of the disposal unit and

  1. Special Analysis: Disposal Plan for Pit 38 at Technical Area 54, Area G

    International Nuclear Information System (INIS)

    French, Sean B.; Shuman, Rob

    2012-01-01

    have been made to utilize the remaining disposal capacity within MDA G to the greatest extent possible. One approach for doing this has been to dispose of low-activity waste from cleanup operations at LANL in the headspace of selected disposal pits. Waste acceptance criteria (WAC) for the material placed in the headspace of pits 15, 37, and 38 have been developed (LANL, 2010) and the impacts of placing waste in the headspace of these units has been evaluated (LANL, 2012a). The efforts to maximize disposal efficiency have taken on renewed importance because of the disposal demands placed on MDA G by the large volumes of waste that are being generated at LANL by cleanup efforts. For example, large quantities of waste were recently generated by the retrieval of waste formerly disposed of at TA-21, MDA B. A portion of this material has been disposed of in the headspace of pit 38 in compliance with the WAC developed for that disposal strategy; a large amount of waste has also been sent to off-site facilities for disposal. Nevertheless, large quantities of MDA B waste remain that require disposal. An extension of pit 38 was proposed to provide the disposal capacity that will be needed to dispose of institutional waste and MDA B waste through 2013. A special analysis was prepared to evaluate the impacts of the pit extension (LANL, 2012b). The analysis concluded that the disposal unit could be extended with modest increases in the exposures projected for the Area G performance assessment and composite analysis, as long as limits were placed on the radionuclide concentrations in the waste that is placed in the headspace of the pit. Based, in part, on the results of the special analysis, the extension of pit 38 was approved and excavation of the additional disposal capacity was started in May 2012. The special analysis presented here uses performance modeling to identify a disposal plan for the placement of waste in pit 38. The modeling uses a refined design of the disposal unit

  2. Chemical decontamination method for radioactive metal waste

    International Nuclear Information System (INIS)

    Onuma, Tsutomu; Akimoto, Hidetoshi

    1991-01-01

    The invention relates to a decontamination method for radioactive metal waste products derived from equipment that handles radioactive materials whose surfaces have been contaminated; in particular it concerns a decontamination method that reduces the amount of radioactive waste by decontaminating radioactive waste substances to a level of radioactivity in line with normal waste products. In order to apply chemical decontamination to metal waste products whose surfaces are divided into carbon steel waste and stainless steel waste; the carbon steel waste is treated using only a primary process in which the waste is immersed in a sulfuric acid solution, while the stainless steel waste must be treated with both the primary process and then electrolytically reduces it for a specific length of time and a secondary process that uses a solution of sulfuric acid mixed with oxidizing metal salts. The method used to categorize metal waste into carbon steel waste and stainless steel waste involves determining the presence, or absence, of magnetism. Voltage is applied for a fixed duration; once that has stopped, electrolytic reduction repeats the operative cycle of applying, then stopping voltage until the potential of the radioactive metal waste is retained in the active region. 1 fig. 2 tabs

  3. MONITORING METAL POLLUTION LEVELS IN MINE WASTES AROUND A COAL MINE SITE USING GIS

    Directory of Open Access Journals (Sweden)

    D. Sanliyuksel Yucel

    2017-11-01

    Full Text Available In this case study, metal pollution levels in mine wastes at a coal mine site in Etili coal mine (Can coal basin, NW Turkey are evaluated using geographical information system (GIS tools. Etili coal mine was operated since the 1980s as an open pit. Acid mine drainage is the main environmental problem around the coal mine. The main environmental contamination source is mine wastes stored around the mine site. Mine wastes were dumped over an extensive area along the riverbeds, and are now abandoned. Mine waste samples were homogenously taken at 10 locations within the sampling area of 102.33 ha. The paste pH and electrical conductivity values of mine wastes ranged from 2.87 to 4.17 and 432 to 2430 μS/cm, respectively. Maximum Al, Fe, Mn, Pb, Zn and Ni concentrations of wastes were measured as 109300, 70600, 309.86, 115.2, 38 and 5.3 mg/kg, respectively. The Al, Fe and Pb concentrations of mine wastes are higher than world surface rock average values. The geochemical analysis results from the study area were presented in the form of maps. The GIS based environmental database will serve as a reference study for our future work.

  4. Monitoring Metal Pollution Levels in Mine Wastes around a Coal Mine Site Using GIS

    Science.gov (United States)

    Sanliyuksel Yucel, D.; Yucel, M. A.; Ileri, B.

    2017-11-01

    In this case study, metal pollution levels in mine wastes at a coal mine site in Etili coal mine (Can coal basin, NW Turkey) are evaluated using geographical information system (GIS) tools. Etili coal mine was operated since the 1980s as an open pit. Acid mine drainage is the main environmental problem around the coal mine. The main environmental contamination source is mine wastes stored around the mine site. Mine wastes were dumped over an extensive area along the riverbeds, and are now abandoned. Mine waste samples were homogenously taken at 10 locations within the sampling area of 102.33 ha. The paste pH and electrical conductivity values of mine wastes ranged from 2.87 to 4.17 and 432 to 2430 μS/cm, respectively. Maximum Al, Fe, Mn, Pb, Zn and Ni concentrations of wastes were measured as 109300, 70600, 309.86, 115.2, 38 and 5.3 mg/kg, respectively. The Al, Fe and Pb concentrations of mine wastes are higher than world surface rock average values. The geochemical analysis results from the study area were presented in the form of maps. The GIS based environmental database will serve as a reference study for our future work.

  5. Trace metal depositional patterns from an open pit mining activity as revealed by archived avian gizzard contents

    Energy Technology Data Exchange (ETDEWEB)

    Bendell, L.I., E-mail: bendell@sfu.ca

    2011-02-15

    Archived samples of blue grouse (Dendragapus obscurus) gizzard contents, inclusive of grit, collected yearly between 1959 and 1970 were analyzed for cadmium, lead, zinc, and copper content. Approximately halfway through the 12-year sampling period, an open-pit copper mine began activities, then ceased operations 2 years later. Thus the archived samples provided a unique opportunity to determine if avian gizzard contents, inclusive of grit, could reveal patterns in the anthropogenic deposition of trace metals associated with mining activities. Gizzard concentrations of cadmium and copper strongly coincided with the onset of opening and the closing of the pit mining activity. Gizzard zinc and lead demonstrated significant among year variation; however, maximum concentrations did not correlate to mining activity. The archived gizzard contents did provide a useful tool for documenting trends in metal depositional patterns related to an anthropogenic activity. Further, blue grouse ingesting grit particles during the time of active mining activity would have been exposed to toxicologically significant levels of cadmium. Gizzard lead concentrations were also of toxicological significance but not related to mining activity. This type of 'pulse' toxic metal exposure as a consequence of open-pit mining activity would not necessarily have been revealed through a 'snap-shot' of soil, plant or avian tissue trace metal analysis post-mining activity. - Research Highlights: {yields} Archived gizzard samples reveals mining history. {yields} Grit ingestion exposes grouse to cadmium and lead. {yields} Grit selection includes particles enriched in cadmium. {yields} Cadmium enriched particles are of toxicological significance.

  6. Attenuation of heavy metal leaching from hazardous wastes by co-disposal of wastes

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Wookeun; Shin, Eung Bai [Hanyang Univ., Ansan (Korea, Republic of); Lee, Kil Chul; Kim, Jae Hyung [National Institute of Environmental Research, Seoul (Korea, Republic of)] [and others

    1996-12-31

    The potential hazard of landfill wastes was previously evaluated by examining the extraction procedures for individual waste, although various wastes were co-disposed of in actual landfills. This paper investigates the reduction of extraction-procedure toxicity by co-disposing various combinations of two wastes. When two wastes are mixed homogeneously, the extraction of heavy metals from the waste mixture is critically affected by the extract pH. Thus, co-disposal wastes will have a resultant pH between the pH values of its constituent. The lower the resultant pH, the lower the concentrations of heavy metals in the extract. When these wastes are extracted sequentially, the latter extracted waste has a stronger influence on the final concentration of heavy metals in the extract. Small-scale lysimeter experiments confirm that when heavy-metal-bearing leachates Generated from hazardous-waste lysimeters are passed through a nonhazardous-waste lysimeter filled with compost, briquette ash, or refuse-incineration ashes, the heavy-metal concentration in the final leachates decreases significantly. Thus, the heavy-metal leaching could be attenuated if a less extraction-procedure-toxic waste were placed at the bottom of a landfill. 3 refs., 4 figs., 5 tabs.

  7. Analysis of BY-106 pump pit cover plate

    International Nuclear Information System (INIS)

    Coverdell, B.L.

    1994-01-01

    A new cover for the pump pit of Tank 241-BY-106 has been designed to allow the rotary core exhauster to be hooked up without requiring pit entry, riser modification, or equipment removal. The new pit cover is necessary to allow installation of two risers for reducing exposure, contamination, and waste. Computer analysis indicates that the safety margin of the pit cover plate with two risers is adequate. The computer stress model and input files are attached. The pit cover plate is a replacement for an existing plate; therefore seismic and wind loads were considered for the plate only

  8. Modeling pitting corrosion damage of high-level radioactive-waste containers, with emphasis on the stochastic approach

    Energy Technology Data Exchange (ETDEWEB)

    Henshall, G.A.; Halsey, W.G.; Clarke, W.L.; McCright, R.D.

    1993-01-01

    Recent efforts to identify methods of modeling pitting corrosion damage of high-level radioactive-waste containers are described. The need to develop models that can provide information useful to higher level system performance assessment models is emphasized, and examples of how this could be accomplished are described. Work to date has focused upon physically-based phenomenological stochastic models of pit initiation and growth. These models may provide a way to distill information from mechanistic theories in a way that provides the necessary information to the less detailed performance assessment models. Monte Carlo implementations of the stochastic theory have resulted in simulations that are, at least qualitatively, consistent with a wide variety of experimental data. The effects of environment on pitting corrosion have been included in the model using a set of simple phenomenological equations relating the parameters of the stochastic model to key environmental variables. The results suggest that stochastic models might be useful for extrapolating accelerated test data and for predicting the effects of changes in the environment on pit initiation and growth. Preliminary ideas for integrating pitting models with performance assessment models are discussed. These ideas include improving the concept of container ``failure``, and the use of ``rules-of-thumb`` to take information from the detailed process models and provide it to the higher level system and subsystem models. Finally, directions for future work are described, with emphasis on additional experimental work since it is an integral part of the modeling process.

  9. Modeling pitting corrosion damage of high-level radioactive-waste containers, with emphasis on the stochastic approach

    International Nuclear Information System (INIS)

    Henshall, G.A.; Halsey, W.G.; Clarke, W.L.; McCright, R.D.

    1993-01-01

    Recent efforts to identify methods of modeling pitting corrosion damage of high-level radioactive-waste containers are described. The need to develop models that can provide information useful to higher level system performance assessment models is emphasized, and examples of how this could be accomplished are described. Work to date has focused upon physically-based phenomenological stochastic models of pit initiation and growth. These models may provide a way to distill information from mechanistic theories in a way that provides the necessary information to the less detailed performance assessment models. Monte Carlo implementations of the stochastic theory have resulted in simulations that are, at least qualitatively, consistent with a wide variety of experimental data. The effects of environment on pitting corrosion have been included in the model using a set of simple phenomenological equations relating the parameters of the stochastic model to key environmental variables. The results suggest that stochastic models might be useful for extrapolating accelerated test data and for predicting the effects of changes in the environment on pit initiation and growth. Preliminary ideas for integrating pitting models with performance assessment models are discussed. These ideas include improving the concept of container ''failure'', and the use of ''rules-of-thumb'' to take information from the detailed process models and provide it to the higher level system and subsystem models. Finally, directions for future work are described, with emphasis on additional experimental work since it is an integral part of the modeling process

  10. Biohydrometallurgical methods for metals recovery from waste materials

    OpenAIRE

    J. Willner; J. Kadukova; A. Fornalczyk; M. Saternus

    2015-01-01

    The article draws attention to recently conducted research of bacterial leaching of metals from various polymetallic waste. These wastes are the carriers of valuable metals: base metals, precious and platinum group metals (e.g. electronic waste, spent catalysts) or rare earth elements.

  11. Biohydrometallurgical methods for metals recovery from waste materials

    Directory of Open Access Journals (Sweden)

    J. Willner

    2015-01-01

    Full Text Available The article draws attention to recently conducted research of bacterial leaching of metals from various polymetallic waste. These wastes are the carriers of valuable metals: base metals, precious and platinum group metals (e.g. electronic waste, spent catalysts or rare earth elements.

  12. Electrochemical tests for pitting and crevice corrosion susceptibility

    International Nuclear Information System (INIS)

    Postlethwaite, J.

    1983-01-01

    Passive metals are being considered as container materials for the disposal of nuclear waste by deep burial. Localized corrosion is a potential problem and electrochemical techniques have an important role in the assessment of the susceptibility of these container materials to crevice and pitting corrosion. This paper critically reviews both the theoretical background and the experimental details of the electrochemical test methods presently used in both industrial and scientific studies of localized corrosion in both halide and non-halide solutions and identifies those areas where theory and experimental behaviour are in agreement and those areas for which there is neither well established theory nor an experimental test method

  13. Chemical decontamination method for radioactive metal waste

    International Nuclear Information System (INIS)

    Tanaka, Akio; Onuma, Tsutomu; Yamazaki, Sei; Miura, Haruki.

    1993-01-01

    The present invention provides a chemical decontamination method for radioactive metal wastes, which are generated from radioactive material handling facilities and the surfaces of which are contaminated by radioactive materials. That is, it has a feature of applying acid dissolution simultaneously with mechanical grinding. The radioactive metal wastes are contained in a vessel such as a barrel together with abrasives in a sulfuric acid solution and rotated at several tens rotation per minute. By such procedures for the radioactive metal wastes, (1) cruds and passive membranes are mechanically removed, (2) exposed mother metal materials are uniformly brought into contact with sulfuric acid and further (3) the mother metal materials dissolve the cruds and the passive membranes also chemically by a reducing dissolution (so-called local cell effect). According to the method of the present invention, stainless steel metal wastes having cruds and passive membranes can rapidly and efficiently be decontaminated to a radiation level equal with that of ordinary wastes. (I.S.)

  14. Remaining Sites Verification Package for the 128-F-2, 100-F Burning Pit Waste Site, Waste Site Reclassification Form 2008-031

    Energy Technology Data Exchange (ETDEWEB)

    J. M. Capron

    2008-12-01

    The 128-F-2 waste site consisted of multiple burn and debris filled pits located directly east of the 107-F Retention Basin and approximately 30.5 m east of the northeast corner of the 100-F Area perimeter road that runs along the riverbank. The burn pits were used for incinerating nonradioactive, combustible materials from 1945 to 1965. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

  15. Bingham Pump Outage Pits: Environmental information document

    International Nuclear Information System (INIS)

    Pekkala, R.O.; Jewell, C.E.; Holmes, W.G.; Marine, I.W.

    1987-03-01

    Seven waste sites known as the Bingham Pump Outage Pits located in areas of the Savannah River Plant (SRP) received solid waste containing an estimated 4 Ci of low-level radioactivity in 1957-1958. These sites were subsequently backfilled and have been inactive since that time. Most of the radioactivity at the Bingham Pump Outage Pits has been eliminated by radioactive decay. A total of approximately 1 Ci of activity (primarily 137 Cs and 90 Sr) is estimated to remain at the seven sites. The closure options considered for the Bingham Pump Outage Pits are waste removal and closure, no waste removal and closure, and no action. The predominant pathways for human exposure to chemical and/or radioactive constituents are through surface, subsurface, and atmospheric transport. Modeling calculations were made to determine the risks to human population via these general pathways for the three postulated closure options. An ecological assessment was conducted to predict the environmental impacts on aquatic and terrestrial biota. The relative costs for each of the closure options were estimated. Evaluation indicates that the relative human health risks for all closure options are small. The greatest public risk would occur after the waste site was released to unrestricted public use (assumed to occur in Year 2085) via the groundwater pathway to a well. The cost estimates show that the waste removal and closure option is the most expensive (89.6 million dollars). The cost of the no waste removal and the no action options is $800,000. 35 refs., 26 figs., 47 tabs

  16. Studies in pitting corrosion on archaeological bronzes. Copper

    International Nuclear Information System (INIS)

    Bresle, Aa.; Saers, J.; Arrhenius, B.

    1983-01-01

    Copper has been proposed as a canister material for use in the long-term storage of radioactive waste from nuclear power reactors. The storage period has been set to at least 100 000 years, during which time the copper cylinders must remain intact so that the contained waste has no possibility of leaking out. In this work, the pitting factor in archaelogical copper objects have been determined. The absolute values of the pitting factor obtained are generally very low. In the case of the most thoroughly studied material the pitting factor is only slightly more than three units. Nor does the native copper, with a presumed burial period of about 8000 years, exhibit particularly high values. In summary, it can therefore be concluded that the present study does not provide support for the assumption of extremely high pitting factors in copper-base material that has been buried for periods of several millenia. (G.B.)

  17. Corrective Action Decision Document for Corrective Action Unit 140: Waste Dumps, Burn Pits, and Storage Area, Nevada Test Site, Nevada, Revision 1 with ROTC 1

    International Nuclear Information System (INIS)

    Boehlecke, Robert

    2004-01-01

    This Corrective Action Decision Document (CADD) has been prepared for Corrective Action Unit (CAU) 140: Waste Dumps, Burn Pits, and Storage Area, Nevada Test Site (NTS), Nevada, in accordance with the ''Federal Facility Agreement and Consent Order'' (1996). Corrective Action Unit 140 is located within Areas 5, 22, and 23 of the NTS and is comprised of the following corrective action sites (CASs): 05-08-01, Detonation Pits; 05-08-02, Debris Pits; 05-17-01, Hazardous Waste Accumulation Site (Buried); 05-19-01, Waste Disposal Site; 05-23-01, Gravel Gertie; 05-35-01, Burn Pit; 05-99-04, Burn Pit; 22-99-04, Radioactive Waste Dump; and 23-17-01, Hazardous Waste Storage Area. The purpose of this CADD is to identify and provide a rationale for the recommendation of a corrective action alternative for each CAS within CAU 140. Corrective action investigation activities were performed from November 13 through December 11, 2002. Additional sampling to delineate the extent of contaminants of concern (COCs) was conducted on February 4 and March 18 and 19, 2003. Corrective action investigation activities were performed as set forth in the Corrective Action Investigation Plan for CAU 140. Analytes detected during the corrective action investigation were evaluated against appropriate preliminary action levels to identify COCs for each CAS. Assessment of the data generated from investigation activities revealed the following: (1) CAS 05-08-01 contains the COCs lead and the radioisotope thorium-234 in the surface soil at sample location A05. (2) CAS 05-23-01 did not have any COCs identified during the field investigation; however, based on historical knowledge of activities at this site, the interior of the Gravel Gertie is considered contaminated with uranium. (3) CAS 23-17-01 contains the COC total petroleum hydrocarbons (diesel-range organics) at location J20 at a depth of 9 to 10 feet below ground surface. (4) No COCs were identified at CASs 05-08-02, 05-17-01, 05-19-01, 05

  18. Open pit mining profit maximization considering selling stage and waste rehabilitation cost

    Science.gov (United States)

    Muttaqin, B. I. A.; Rosyidi, C. N.

    2017-11-01

    In open pit mining activities, determination of the cut-off grade becomes crucial for the company since the cut-off grade affects how much profit will be earned for the mining company. In this study, we developed a cut-off grade determination mode for the open pit mining industry considering the cost of mining, waste removal (rehabilitation) cost, processing cost, fixed cost, and selling stage cost. The main goal of this study is to develop a model of cut-off grade determination to get the maximum total profit. Secondly, this study is also developed to observe the model of sensitivity based on changes in the cost components. The optimization results show that the models can help mining company managers to determine the optimal cut-off grade and also estimate how much profit that can be earned by the mining company. To illustrate the application of the models, a numerical example and a set of sensitivity analysis are presented. From the results of sensitivity analysis, we conclude that the changes in the sales price greatly affects the optimal cut-off value and the total profit.

  19. Production of metal waste forms from spent fuel treatment

    International Nuclear Information System (INIS)

    Westphal, B.R.; Keiser, D.D.; Rigg, R.H.; Laug, D.V.

    1995-01-01

    Treatment of spent nuclear fuel at Argonne National Laboratory consists of a pyroprocessing scheme in which the development of suitable waste forms is being advanced. Of the two waste forms being proposed, metal and mineral, the production of the metal waste form utilizes induction melting to stabilize the waste product. Alloying of metallic nuclear materials by induction melting has long been an Argonne strength and thus, the transition to metallic waste processing seems compatible. A test program is being initiated to coalesce the production of the metal waste forms with current induction melting capabilities

  20. Radionuclide and metal contamination in pit lakes in former U mining sites in Central Asia

    Energy Technology Data Exchange (ETDEWEB)

    Skipperud, L.; Rosseland, B.O.; Heier, L.S.; Salbu, B. [Centre for Environmental Radioactivity - CERAD, Norwegian University of Life Sciences - NMBU (Norway); Stegnar, P. [Josef Stefan Institute (Slovenia); Yunusov, M. [IA Vostokredmet (Tajikistan); Burkitbaev, L.M. [Al-Farabi Kazakh National University (Kazakhstan)

    2014-07-01

    The uranium mining industry in the USSR was established in the late 1940's - early 1950's in the former Soviet Republics of Kazakhstan, Kyrgyzstan, Tajikistan and Uzbekistan as part of the nuclear weapon program. In most countries, uranium mining is considered a hazardous step of nuclear materials production, both in terms of radiation doses and in the number of people affected. Key problems have been associated with the transport of uranium and its daughters in aquatic and terrestrial ecosystems, where radionuclides are transferred from air, water, and soils into plants, fish/animals and finally to man. In this paper, special attention is paid to the assessment of radionuclides and metals in Central Asian Pit Lakes. Field works to Kurday, Kasakhstan, and Taboshar, Tajikistan, Pit Lakes have been performed. In addition to sampling of water, fish, sediments, and vegetation, in situ fractionation of water were achieved. The concentrations of U and associated trace metals were enriched in the Kurday Pit Lake and in the artesian water at the Kurday site (U exceeding the WHO guideline value for drinking water), and decreased downstream from the mining area. Uranium, As, Mo and Ni were predominantly present as mobile low molecular mass species in waters, while a significant proportion of Cr, Mn and Fe were associated with colloids and particles. Due to oxidation of divalent iron in the artesian ground water upon contact with air, Fe served as scavenger for other elements, and peak concentrations of U, Ra-isotopes, As and Mn were seen. The U concentrations in water from Taboshar Pit Lake (2.0 mg U/L) were higher than waters collected in other areas in Tajikistan. The Pit Lake and the stream water from the tailing mountain were also characterized by elevated concentrations of As, Mo, Mn and Fe, exceeding the WHO recommended values for drinking water. Uranium, As, Mo and Ni were present as low molecular mass species in the waters, and are therefore considered

  1. A brief analysis and description of transuranic wastes in the subsurface disposal area of the radioactive waste management complex at INEL

    International Nuclear Information System (INIS)

    Arrenholz, D.A.; Knight, J.L.

    1991-02-01

    This document presents a brief summary of the wastes and waste types disposed of in the transuranic contaminated portions of the Subsurface Disposal Area during the period 1954 through 1970. Wastes included in this summary are organics, inorganics, metals, radionuclides, and special-case wastes. In addition to summarizing amounts of wastes disposed and describing the wastes, the document also provides information on disposal pit and trench dimensions and contaminated soil volumes. The report also points out discrepancies that exist in available documentation regarding waste and soil volumes and makes recommendations for future efforts at waste characterization. 20 refs., 3 figs., 17 tabs

  2. Decontamination and decommissioning of the SPERT-I seepage pit at the Idaho National Engineering Laboratory. Final report

    International Nuclear Information System (INIS)

    Suckel, R.A.

    1984-11-01

    This report describes the decontamination and decommissioning of the SPERT-I seepage pit. Prior to its decontamination and decommissioning, the seepage pit was surrounded by an earthen dike varying from 2 to 6 ft above the pit bottom. A 6-in., cast iron, underground waste line originated at the pit tank in the reactor building and ran approximately 68 ft to the seepage pit. The soil in the seepage pit contained low-level radioactive contamination. The soil surface was removed to a depth of 2.5 ft and shipped to the Radioactive Waste Management Complex (RWMC). The waste line that contained fixed contamination was removed and also sent to the RWMC. The pit was backfilled with radiologically clean soil, reducing the surface activity to background. A permanent marker was erected over the backfilled pit to indicate that presence of residual subsurface radioactive contamination. 5 references, 26 figures, 3 tables

  3. Studies of corrosion in metallic container for storage of high level radioactive wastes; Estudios de corrosion de materiales metalicos para capsulas de almacenamiento de residuos de alta actividad

    Energy Technology Data Exchange (ETDEWEB)

    Azkarate, I; Madina, V; Insausti, M

    1999-11-01

    The metallic container is one of the most important barriers that, along with engineered and natural barriers, will isolate high level nuclear waste in saline and granite geological formations from the geosphere. However, general and localized corrosion modes such as stress corrosion cracking (SCC), pitting, crevice corrosion and hydrogen damage can be active under disposal conditions, so the corrosion behaviour of the metal container material must be carefully studied. Several metals and their alloys have been proposed for the fabrication of nuclear waste containers including carbon steels, stainless steels, titanium and titanium alloys and copper and copper-base alloys. Carbon steels and copper alloys are considered for the two rock formations, titanium is considered for salt environments and the stainless steel only in the case of a granite formation. (Author)

  4. Assessment and cleanup of the Taxi Strip waste storage area at LLNL [Lawrence Livermore National Laboratory

    International Nuclear Information System (INIS)

    Buerer, A.

    1983-01-01

    In September 1982 the Hazards Control Department of the Lawrence Livermore National Laboratory (LLNL) began a final radiological survey of a former low-level radioactive waste storage area called the Taxi Strip so that the area could be released for construction of an office building. Collection of soil samples at the location of a proposed sewer line led to the discovery of an old disposal pit containing soil contaminated with low-level radioactive waste and organic solvents. The Taxi Strip area was excavated leading to the discovery of three additional small pits. The clean-up of Pit No. 1 is considered to be complete for radioactive contamination. The results from the chlorinated solvent analysis of the borehole samples and the limited number of samples analyzed by gas chromatography/mass spectrometry indicate that solvent clean-up at this pit is complete. This is being verified by gas chromatography/mass spectrometry analysis of a few additional soil samples from the bottom sides and ends of the pit. As a precaution, samples are also being analyzed for metals to determine if further excavation is necessary. Clean-up of Pits No. 2 and No. 3 is considered to be complete for radioactive and solvent contamination. Results of analysis for metals will determine if excavation is complete. Excavation of Pit No. 4 which resulted from surface leakage of radioactive contamination from an evaporation tray is complete

  5. Cogema experience on retrieving and conditioning solid radwaste previously stored in pits. The La Hague north west pit case

    International Nuclear Information System (INIS)

    Bodin, F.; Alexandre, D.; Fournier, Ph.

    2000-01-01

    Short lived, low and medium level waste called 'technological waste' produced by the La Hague Reprocessing Plant have been stored in the La Hague North-West concrete-lined pits until implementation at ANDRA's Centre de Stockage de la Manche (CSM). COGEMA decided to retrieve and condition 11,000 m 3 of humid solid radwaste, stored in bulk in pits. This report describes the experience gained from February 1990 to December 1998, taking into account radwaste and integrated dose rate results conditioning such waste. The procedures and means used and improved by COGEMA to comply with ANDRA's storage standards and the ever-decreasing financial costs generated by the workers, allowed to retrieve and condition 11,000 m 3 of old solid radwaste with competitive costs and in complete safety and protection of the environment. (authors)

  6. Prediction of pressure of bentonite buffer in model test of disposal pit for high-level radioactive waste

    International Nuclear Information System (INIS)

    Komine, Hideo; Osada, Toru; Takao, Hajime; Ueda, Hiroyoshi

    2013-01-01

    Bentonite-based buffer materials for high-level radioactive waste (HLW) disposal are expected to fill up the space between buffer and a wall of the disposal pit, and/or between buffer and an waste-container called as overpack by its swelling deformation. That is called as self-sealing ability. This study performs the model tests simulated the relationship between buffer and space mentioned above. It also investigates the validity of the theoretical equations for evaluating the swelling characteristics of bentonite-based buffer and backfill material, which were proposed in Komine and Ogata (2003, 2004), by comparing the calculations and the experimental results. (author)

  7. The Influence of Radiation on Pit Solution Chemistry as it Pertains to the Transition from Metastable to Stable Pitting in Steels

    International Nuclear Information System (INIS)

    Galuszka-Muga, Barbara; Muga, Luis M.

    2006-01-01

    Previous work relevant to current efforts is summarized. A description of an improved version of a new electrochemical probe, the ArtPit, is given. The distinct feature of the probe for investigating metastable pitting of carbon steels is specified and compared to other approaches. The electrochemical response of the ArtPit under the gamma irradiation and elevated temperature conditions that occur at high level waste (HLW) storage tanks is presented. In particular, the Tafel slope determinations and chemical analyses of the ArtPit confined volume electrolyte are described. Based on results a possible approach for reducing the corrosion rate of HLW tank walls is suggested. Additional statistical analysis of the occurrence of short duration (passivated pits) and long term (stable pitting) electrochemical pulses (current surges) during exposure confirm that radiation enhances the occurrence of both more and smaller sized pits due to increased likelihood of repassivation

  8. A brief analysis and description of transuranic wastes in the Subsurface Disposal Area of the radioactive waste management complex at INEL

    International Nuclear Information System (INIS)

    Arrenholz, D.A.; Knight, J.L.

    1991-08-01

    This document presents a brief summary of the wastes and waste types disposed of in the transuranic contaminated portions of the Subsurface Disposal Area of the radioactive waste management complex at Idaho National Engineering Laboratory from 1954 through 1970. Wastes included in this summary are organics, inorganics, metals, radionuclides, and atypical wastes. In addition to summarizing amounts of wastes disposed and describing the wastes, the document also provides information on disposal pit and trench dimensions and contaminated soil volumes. The report also points out discrepancies that exist in available documentation regarding waste and soil volumes and make recommendations for future efforts at waste characterization. 19 refs., 3 figs., 17 tabs

  9. A brief analysis and description of transuranic wastes in the Subsurface Disposal Area of the radioactive waste management complex at INEL

    Energy Technology Data Exchange (ETDEWEB)

    Arrenholz, D.A.; Knight, J.L.

    1991-08-01

    This document presents a brief summary of the wastes and waste types disposed of in the transuranic contaminated portions of the Subsurface Disposal Area of the radioactive waste management complex at Idaho National Engineering Laboratory from 1954 through 1970. Wastes included in this summary are organics, inorganics, metals, radionuclides, and atypical wastes. In addition to summarizing amounts of wastes disposed and describing the wastes, the document also provides information on disposal pit and trench dimensions and contaminated soil volumes. The report also points out discrepancies that exist in available documentation regarding waste and soil volumes and make recommendations for future efforts at waste characterization. 19 refs., 3 figs., 17 tabs.

  10. 200 West Ash Pit Demolition Site closure plan

    International Nuclear Information System (INIS)

    1992-11-01

    The Hanford Facility is owned by the US Government and operated by the US Department of Energy, Richland Field Office. Dangerous waste and mixed waste (containing both radioactive and dangerous components) are managed and produced on the Hanford Facility. Westinghouse Hanford Company is a major contractor to the US Department of Energy, Richland Field Office and serves as cooperator of the 200 West Ash Pit Demolition Site, the unit addressed in this closure plan. The 200 West Ash Pit Demolition Site Closure Plan consists of a Part A Permit Application (Revision 3) and a closure plan. An explanation of the Part A Permit Application revision is provided at the beginning of the Part A section. The closure plan consists of nine chapters and three appendices. This 200 West Ash Pit Demolition Site Closure Plan submittal contains information current as of October 15, 1992

  11. Metal decontamination for waste minimization using liquid metal refining technology

    International Nuclear Information System (INIS)

    Joyce, E.L. Jr.; Lally, B.; Ozturk, B.; Fruehan, R.J.

    1993-01-01

    The current Department of Energy Mixed Waste Treatment Project flowsheet indicates that no conventional technology, other than surface decontamination, exists for metal processing. Current Department of Energy guidelines require retrievable storage of all metallic wastes containing transuranic elements above a certain concentration. This project is in support of the National Mixed Low Level Waste Treatment Program. Because of the high cost of disposal, it is important to develop an effective decontamination and volume reduction method for low-level contaminated metals. It is important to be able to decontaminate complex shapes where surfaces are hidden or inaccessible to surface decontamination processes and destruction of organic contamination. These goals can be achieved by adapting commercial metal refining processes to handle radioactive and organic contaminated metal. The radioactive components are concentrated in the slag, which is subsequently vitrified; hazardous organics are destroyed by the intense heat of the bath. The metal, after having been melted and purified, could be recycled for use within the DOE complex. In this project, we evaluated current state-of-the-art technologies for metal refining, with special reference to the removal of radioactive contaminants and the destruction of hazardous organics. This evaluation was based on literature reports, industrial experience, plant visits, thermodynamic calculations, and engineering aspects of the various processes. The key issues addressed included radioactive partitioning between the metal and slag phases, minimization of secondary wastes, operability of the process subject to widely varying feed chemistry, and the ability to seal the candidate process to prevent the release of hazardous species

  12. Remaining Sites Verification Package for the 128-F-2, 100-F Burning Pit Waste Site. Attachment to Waste Site Reclassification Form 2008-031

    International Nuclear Information System (INIS)

    Capron, J.M.

    2008-01-01

    The 128-F-2 waste site consisted of multiple burn and debris filled pits located directly east of the 107-F Retention Basin and approximately 30.5 m east of the northeast corner of the 100-F Area perimeter road that runs along the riverbank. The burn pits were used for incinerating nonradioactive, combustible materials from 1945 to 1965. In accordance with this evaluation, the verification sampling results support a reclassification of this site to Interim Closed Out. The current site conditions achieve the remedial action objectives and the corresponding remedial action goals established in the Remaining Sites ROD. The results of verification sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River

  13. Tale of two pit lakes: initial results of a three-year study of the Main Zone and Waterline pit lakes near Houston, British Columbia, Canada

    Science.gov (United States)

    Crusius, John; Pieters, R.; Leung, A.; Whittle, P.; Pedersen, T.; Lawrence, G.; McNee, J.J.

    2003-01-01

    Pit lakes are becoming increasingly common in North America as well as in the rest of the world. They are created as openpit mines fill passively with ground water and surface inflows on cessation of mining activity. In many instances, the water quality in these pit lakes does not meet regulatory requirements due to a number of influences. The most important are the oxidation of sulfide minerals and the associated release of acid and metals and the flushing of soluble metals during pit filling. Examples of pit lakes with severe water-quality problems include the Berkeley Pit lake (Butte, MT) and the Liberty Pit lake (Nevada), whose waters are characterized by a pH near 3 and Cu concentrations as high as ~150 mg/L (Miller et al., 1996; Davis and Eary, 1997). The importance of the problem can be seen in the fact that some of these sites in the United States are Superfund sites.

  14. Flare pits wastes remediation by low temperature oxidation

    International Nuclear Information System (INIS)

    Catalan, L. J. L.; Jamaluddin, A. K. M.; Mehta, R.; Moore, R. G.; Okazawa, N.; Ursenbach, M.

    1997-01-01

    The remediation of contaminated soil in oilfield sites, flare pits in particular, is subject to strict environmental regulations. Most current remediation techniques such as biological or thermal treatment are not particularly effective in highly contaminated sites, or effective only at costs that are considered prohibitive. This contribution describes a cost-effective method for the treatment of contaminated soil in-situ. The proposed treatment involves low temperature oxidation which converts the hydrocarbons in the contaminated soil to inert coke. In laboratory studies contaminated soil was oxidized with air at temperatures between 150 degrees C and 170 degrees C for three weeks. After the three week treatment extractable hydrocarbon levels were reduced to less than 0.1 per cent. Bioassays also demonstrated that toxicity associated with hydrocarbons was eliminated. Salts and metals remaining in the soil after treatment were removed by leaching with water. Low temperature oxidation requires no special equipment; it can occur under conditions and with equipment that are readily available in an oilfield setting. 5 refs., 8 tabs., 7 figs

  15. Perspective of metal encapsulation of waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-01-01

    A conceptual flow sheet is presented for encapsulating solid, stabilized calcine (e.g., supercalcine) in a solid lead alloy, using existing or developing technologies. Unresolved and potential problem areas of the flow sheet are outlined and suggestions are made as how metal encapsulation might be applied to other solid wastes from the fuel cycle. It is concluded that metal encapsulation is a technique applicable to many forms of solid wastes and is likely to meet future waste isolation criteria and regulations

  16. Metallurgical recovery of metals from electronic waste: A review

    International Nuclear Information System (INIS)

    Cui Jirang; Zhang Lifeng

    2008-01-01

    Waste electric and electronic equipment, or electronic waste, has been taken into consideration not only by the government but also by the public due to their hazardous material contents. In the detailed literature survey, value distributions for different electronic waste samples were calculated. It is showed that the major economic driver for recycling of electronic waste is from the recovery of precious metals. The state of the art in recovery of precious metals from electronic waste by pyrometallurgical processing, hydrometallurgical processing, and biometallurgical processing are highlighted in the paper. Pyrometallurgical processing has been a traditional technology for recovery of precious metals from waste electronic equipment. However, state-of-the-art smelters are highly depended on investments. Recent research on recovery of energy from PC waste gives an example for using plastics in this waste stream. It indicates that thermal processing provides a feasible approach for recovery of energy from electronic waste if a comprehensive emission control system is installed. In the last decade, attentions have been removed from pyrometallurgical process to hydrometallurgical process for recovery of metals from electronic waste. In the paper, hydrometallurgical processing techniques including cyanide leaching, halide leaching, thiourea leaching, and thiosulfate leaching of precious metals are detailed. In order to develop an environmentally friendly technique for recovery of precious metals from electronic scrap, a critical comparison of main leaching methods is analyzed for both economic feasibility and environmental impact. It is believed that biotechnology has been one of the most promising technologies in metallurgical processing. Bioleaching has been used for recovery of precious metals and copper from ores for many years. However, limited research was carried out on the bioleaching of metals from electronic waste. In the review, initial researches on the

  17. Metallurgical recovery of metals from electronic waste: A review

    Energy Technology Data Exchange (ETDEWEB)

    Cui Jirang [Department of Materials Science and Engineering, Norwegian University of Science and Technology (NTNU), Alfred Getz vei 2, N-7491 Trondheim (Norway)], E-mail: Jirang.Cui@material.ntnu.no; Zhang Lifeng [Department of Materials Science and Engineering, Norwegian University of Science and Technology (NTNU), Alfred Getz vei 2, N-7491 Trondheim (Norway)], E-mail: zhanglife@mst.edu

    2008-10-30

    Waste electric and electronic equipment, or electronic waste, has been taken into consideration not only by the government but also by the public due to their hazardous material contents. In the detailed literature survey, value distributions for different electronic waste samples were calculated. It is showed that the major economic driver for recycling of electronic waste is from the recovery of precious metals. The state of the art in recovery of precious metals from electronic waste by pyrometallurgical processing, hydrometallurgical processing, and biometallurgical processing are highlighted in the paper. Pyrometallurgical processing has been a traditional technology for recovery of precious metals from waste electronic equipment. However, state-of-the-art smelters are highly depended on investments. Recent research on recovery of energy from PC waste gives an example for using plastics in this waste stream. It indicates that thermal processing provides a feasible approach for recovery of energy from electronic waste if a comprehensive emission control system is installed. In the last decade, attentions have been removed from pyrometallurgical process to hydrometallurgical process for recovery of metals from electronic waste. In the paper, hydrometallurgical processing techniques including cyanide leaching, halide leaching, thiourea leaching, and thiosulfate leaching of precious metals are detailed. In order to develop an environmentally friendly technique for recovery of precious metals from electronic scrap, a critical comparison of main leaching methods is analyzed for both economic feasibility and environmental impact. It is believed that biotechnology has been one of the most promising technologies in metallurgical processing. Bioleaching has been used for recovery of precious metals and copper from ores for many years. However, limited research was carried out on the bioleaching of metals from electronic waste. In the review, initial researches on the

  18. Acidic pit lakes. The legacy of coal and metal surface mines

    Energy Technology Data Exchange (ETDEWEB)

    Geller, Walter; Schultze, Martin [Helmholtz Centre for Environmental Research - UFZ, Magdeburg (Germany); Wolkersdorfer, Christian (eds.) [Cape Breton Univ., Sydney, NS (Canada). Industrial Research Chair in Mine Water Remediation and Management; International Mine Water Association, Wendelstein (Germany). General Secretary; Kleinmann, Robert

    2013-07-01

    This monograph provides an international perspective on pit lakes in post-mining landscapes, including the problem of geogenic acidification. Much has been learned during the last decade through research and practical experience on how to mitigate or remediate the environmental problems of acidic pit lakes. In the first part of the book, general scientific issues are presented in 21 contributions from the fields of geo-environmental science, water chemistry, lake physics, lake modeling, and on the peculiar biological features that occur in the extreme habitats of acidic pit lakes. Another chapter provides an overview of methods currently used to remediate acidic pit lakes and treat outflowing acidic water. The second part of the book is a collection of regional surveys of pit lake problems from three European countries and Australia, and case studies of various individual representative lakes. A final case study provides an innovative approach to assessing the economic value of new pit lakes and balancing the costs and benefits, a valuable tool for decision makers.

  19. Waste assessment chemical characterization of the Weldon Spring site Raffinate Pitts

    International Nuclear Information System (INIS)

    1989-08-01

    As part of the remedial investigation efforts conducted at the Weldon Spring Site Remedial Action project (WSSRAP), it was recognized that an assessment of the nature and extent of the types of waste in the Weldon Spring Raffinate Pits (WSRP) was necessary to evaluate treatment and disposal alternatives. A sampling plan was developed, therefore, which detailed sample locations, sample parameters, and sampling techniques. The sampling effort consisted of collecting 145 samples from 42 locations. The sampling locations were evenly distributed across each of the four raffinate pits in terms of both area and depth. The samples were analyzed for nitroaromatics, metals, inorganic anions, volatiles, semi-volatiles, PCBs/pesticides, oil and grease, total organic halogens, total organic carbon, cyanides and phenols. The data were then evaluated specific to each pit. At a later date the surface waters of each pit were sampled and similarly analyzed for metals. Samples were also analyzed for radiological contaminants. Information regarding radiological characterization is available in a companion report. 5 figs., 24 tabs

  20. 200 West Area Ash Pit Demolition Site closure plan. Revision 1

    International Nuclear Information System (INIS)

    Ruck, F.R.

    1994-01-01

    The Ash Pit Demolition Site had two known demolition events, the first occurred in November of 1984, and the second occurred in June of 1986. These demolition events were a form of thermal treatment for discarded explosive chemical products. Because the Ash Pit Demolition Site will no longer be used for this thermal activity, the site will be closed. Closure will be conducted pursuant to the requirements of the Washington State Department of Ecology (Ecology) ''Dangerous Waste Regulations'', Washington Administrative Code (WAC) 173-303-610 and 40 Code of Federal Regulations (CFR) 270.1. The 200 West Area Ash Pit Demolition Site Closure Plan consists of a Part A, Form 3, Dangerous Waste Permit Application (Revision 4) and a closure plan. An explanation of the Part A, Form 3, submitted with this closure plan is provided at the beginning of the Part A Section. The closure plan consists of nine chapters and five appendices. This closure plan presents a description of the Ash,Pit Demolition Site, the history of the waste treated, and the approach that will be followed to close the Ash Pit Demolition Site. Because there were no radioactively contaminated chemicals involved in the demolitions, the information on radionuclides is provided for ''information only''. Remediation of any radioactive contamination is not within the scope of this closure plan. Only dangerous constituents derived from Ash Pit Demolition Site operations will be addressed in this closure plan in accordance with WAC 173-303-610(2)(b)(i)

  1. Glassy slags as novel waste forms for remediating mixed wastes with high metal contents

    International Nuclear Information System (INIS)

    Feng, X.; Wronkiewicz, D.J.; Bates, J.K.; Brown, N.R.; Buck, E.C.; Gong, M.; Ebert, W.L.

    1994-01-01

    Argonne National Laboratory (ANL) is developing a glassy slag final waste form for the remediation of low-level radioactive and mixed wastes with high metal contents. This waste form is composed of various crystalline and metal oxide phases embedded in a silicate glass phase. This work indicates that glassy slag shows promise as final waste form because (1) it has similar or better chemical durability than high-level nuclear waste (HLW) glasses, (2) it can incorporate large amounts of metal wastes, (3) it can incorporate waste streams having low contents of flux components (boron and alkalis), (4) it has less stringent processing requirements (e.g., viscosity and electric conductivity) than glass waste forms, (5) its production can require little or no purchased additives, which can result in greater reduction in waste volume and overall treatment costs. By using glassy slag waste forms, minimum additive waste stabilization approach can be applied to a much wider range of waste streams than those amenable only to glass waste forms

  2. Superfund record of decision (EPA Region 4): Potter's septic tank service pits site, Brunswick County, Sandy Creek, NC. (First remedial action), August 1992. Final report

    International Nuclear Information System (INIS)

    1992-01-01

    The 5-acre Potter's Septic Tank Service Pits (Potter's Pits) is located in a rural section of Brunswick County, North Carolina. The site is situated within a residential community known as the Town of Sandy Creek. Disposal practices consisted of placing petroleum waste products and septic tank sludges either in shallow unlined pits or directly on the land surface. The ROD addresses the ground water treatment and contaminated soils at the site. Primary contaminants of concern affecting surface and subsurface soil are VOCs and semi-VOCs, including napthalene, metals, and pesticides. Ground water is contaminated with VOCs, including benzene, ethyl benzene, toluene; other organics including naphthalene, and xylenes; and metals, including chromium and lead. The selected remedial action for the site includes excavating all soils that exceed the soil clean-up standards; treating contaminated soils by using an onsite ex-situ thermal desorption process; performing secondary treatment of the concentrated organic contaminants, and sampling and analyzing the treatment residue

  3. Heavy metals in municipal solid waste deposits

    Energy Technology Data Exchange (ETDEWEB)

    Flyhammar, P.

    1997-12-01

    Extensive use of heavy metals in modern society influences routes followed by fluxes on the surface of the Earth. The changed flow paths may be harmful for the balance of biological systems at different levels, micro-organisms, human beings and whole ecosystems, since the toxicity of heavy metals is determined by their concentrations and chemical forms. Despite the low mobility of heavy metals (Zn, Cu, Pb, Cr, Ni and Cd) in municipal landfills, it was found that extensive transformations of the binding forms of heavy metal take place within the waste mass during the degradation of the waste. These changes appear to be closely related to the development of early diagenetic solid phases, i.e. new secondary solid phases formed in the waste. The heavy metals often constitute a minor part of these phases and the bindings include several forms such as adsorption, complexation, coprecipitation, precipitation, etc. It was also found that the associations between heavy metals and solid phases are dominated by several binding forms to one specific substrate rather than bindings to various solid phases. The mobility of iron and manganese seems to increase during the processes involved in waste degradation due to the solution of oxide/hydroxide phases, while the heavy metals appear to become less mobile due to their binding to organic compounds and sulphides. However, one exception in this case may be nickel. Another aspect of the transformation of heavy metals is the accumulation of pools of heavy metals which can become susceptible to environmental changes, such as oxidation or acidification. However, the risk of increased mobilization caused by lower pH values seem to be limited since municipal solid waste has a large buffer capacity. 66 refs, 9 figs, 3 tabs 66 refs, 9 figs, 3 tabs

  4. Accumulation of heavy metals by vegetables grown in mine wastes

    Energy Technology Data Exchange (ETDEWEB)

    Cobb, G.P.; Sands, K.; Waters, M.; Wixson, B.G.; Dorward-King, E.

    2000-03-01

    Lead, cadmium, arsenic, and zinc were quantified in mine wastes and in soils mixed with mine wastes. Metal concentrations were found to be heterogeneous in the wastes. Iceberg lettuce, Cherry Belle radishes, Roma bush beans, and Better Boy tomatoes were cultivated in mine wastes and in waste-amended soils. Lettuce and radishes had 100% survival in the 100% mine waste treatments compared to 0% and 25% survival for tomatoes and beans, respectively. Metal concentrations were determined in plant tissues to determine uptake and distribution of metals in the edible plant parts. Individual soil samples were collected beneath each plant to assess metal content in the immediate plant environment. This analysis verified heterogeneous metal content of the mine wastes. The four plant species effectively accumulated and translocated lead, cadmium, arsenic, and zinc. Tomato and bean plants contained the four metals mainly in the roots and little was translocated to the fruits. Radish roots accumulated less metals compared to the leaves, whereas lettuce roots and leaves accumulated similar concentrations of the four metals. Lettuce leaves and radish roots accumulated significantly more metals than bean and tomato fruits. This accumulation pattern suggests that consumption of lettuce leaves or radish roots from plants grown in mine wastes would pose greater risks to humans and wildlife than would consumption of beans or tomatoes grown in the same area. The potential risk may be mitigated somewhat in humans, as vegetables grown in mine wastes exhibited stunted growth and chlorosis.

  5. Methods for recovering precious metals from industrial waste

    Science.gov (United States)

    Canda, L.; Heput, T.; Ardelean, E.

    2016-02-01

    The accelerated rate of industrialization increases the demand for precious metals, while high quality natural resources are diminished quantitatively, with significant operating costs. Precious metals recovery can be successfully made from waste, considered to be secondary sources of raw material. In recent years, concerns and interest of researchers for more increasing efficient methods to recover these metals, taking into account the more severe environmental protection legislation. Precious metals are used in a wide range of applications, both in electronic and communications equipment, spacecraft and jet aircraft engines and for mobile phones or catalytic converters. The most commonly recovered precious metals are: gold from jewellery and electronics, silver from X- ray films and photographic emulsions, industrial applications (catalysts, batteries, glass/mirrors), jewellery; platinum group metals from catalytic converters, catalysts for the refining of crude oil, industrial catalysts, nitric acid manufacturing plant, the carbon-based catalyst, e-waste. An important aspect is the economic viability of recycling processes related to complex waste flows. Hydrometallurgical and pyrometallurgical routes are the most important ways of processing electrical and electronic equipment waste. The necessity of recovering precious metals has opened new opportunities for future research.

  6. Pit 9 project: A private sector initiative

    International Nuclear Information System (INIS)

    Macdonald, D.W.; Hughes, F.P.; Burton, B.N.

    1993-01-01

    This report discusses the Pit 9 Comprehensive Demonstration which is intended to demonstrate a cost-effective approach to remediate an Idaho National Engineering Laboratory (INEL) waste disposal pit through a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Interim Action. The remediation will include additional requirements, if needed, to provide high confidence that only minor additional work would be necessary to accomplish the final closure as part of the overall final closure strategy for the INEL's Subsurface Disposal Area (SDA)

  7. Nuclear waste storage container with metal matrix

    Science.gov (United States)

    Sump, Kenneth R.

    1978-01-01

    The invention relates to a storage container for high-level waste having a metal matrix for the high-level waste, thereby providing greater impact strength for the waste container and increasing heat transfer properties.

  8. Nuclear waste storage container with metal matrix

    International Nuclear Information System (INIS)

    Sump, K.R.

    1978-01-01

    The invention relates to a storage container for high-level waste having a metal matrix for the high-level waste, thereby providing greater impact strength for the waste container and increasing heat transfer properties

  9. Pit disassembly and conversion demonstration environmental assessment and research and development activities

    International Nuclear Information System (INIS)

    1998-08-01

    A significant portion of the surplus plutonium is in the form of pits, a nuclear weapons component. Pits are composed of plutonium which is sealed in a metallic shell. These pits would need to be safely disassembled and permanently converted to an unclassified form that would be suitable for long-term disposition and international inspection. To determine the feasibility of an integrated pit disassembly and conversion system, a Pit Disassembly and Conversion Demonstration is proposed to take place at the Los Alamos National Laboratory (LANL). This demonstration would be done in existing buildings and facilities, and would involve the disassembly of up to 250 pits and conversion of the recovered plutonium to plutonium metal ingots and plutonium dioxide. This demonstration also includes the conversion of up to 80 kilograms of clean plutonium metal to plutonium dioxide because, as part of the disposition process, some surplus plutonium metal may be converted to plutonium dioxide in the same facility as the surplus pits. The equipment to be used for the proposed demonstration addressed in this EA would use some parts of the Advanced Recovery and Integrated Extraction System (ARIES) capability, other existing equipment/capacities, plus new equipment that was developed at other sites. In addition, small-scale R and D activities are currently underway as part of the overall surplus plutonium disposition program. These R and D activities are related to pit disassembly and conversion, MOX fuel fabrication, and immobilization (in glass and ceramic forms). They are described in Section 7.0. On May 16, 1997, the Office of Fissile Materials Disposition (MD) notified potentially affected states and tribes that this EA would be prepared in accordance with NEPA. This EA has been prepared to provide sufficient information for DOE to determine whether a Finding of No Significant Impact (FONSI) is warranted or whether an EIS must be prepared

  10. Stochastic models for predicting pitting corrosion damage of HLRW containers

    International Nuclear Information System (INIS)

    Henshall, G.A.

    1991-10-01

    Stochastic models for predicting aqueous pitting corrosion damage of high-level radioactive-waste containers are described. These models could be used to predict the time required for the first pit to penetrate a container and the increase in the number of breaches at later times, both of which would be useful in the repository system performance analysis. Monte Carlo implementations of the stochastic models are described, and predictions of induction time, survival probability and pit depth distributions are presented. These results suggest that the pit nucleation probability decreases with exposure time and that pit growth may be a stochastic process. The advantages and disadvantages of the stochastic approach, methods for modeling the effects of environment, and plans for future work are discussed

  11. SISTEM PENGOLAHAN AIR ASAM TAMBANG PADA WATER POND DAN APLIKASI MODEL ENCAPSULATION IN-PIT DISPOSAL PADA WASTE DUMP TAMBANG BATUBARA (Acid Mine Drainage Treatment System in Water Pond and Application of Encapsulation In-Pit Disposal Model in Waste Dump

    Directory of Open Access Journals (Sweden)

    Andy R. Erwin Wijaya

    2010-03-01

    Full Text Available ABSTRAK Kegiatan pertambangan batubara umumnya dapat menimbulkan dampak negatif terhadap lingkungan di lokasi penambangan. Salah satu dampak negatif yang signifikan adalah terjadinya pencemaran air asam tambang yang dapat merusak fungsi lingkungan seperti komponen air dan tanah. Umumnya lokasi tambang batubara yang berpotensi besar sebagai sumber terbentuknya air asam tambang adalah kolam penampungan air tambang (water pond dan tempat penimbunan material buangan sulfida (waste dump. Penelitian ini bertujuan untuk mengendalikan rembesan air asam tambang yang berasal dari kolam penampungan air (water pond dan mengurangi terbentuknya air asam tambang pada tempat penimbunan material buangan sulfida (waste dunp. Sistem pengendalian pencemaran air asam tambang meliputi pengolahan air asam tambang (water pond dan pengelolaan material sulfida (waste dump. Metode pengolahan air asam tambang adalah menetralisasi air asam dengan reagen alkali. Reagen alkali yang paling efektif dan ekonomis adalah batugamping (kalsium karbonat. Jumlah batugamping yang dibutuhkan untuk menetralkan air asam lambang pada water pond (5040 m3 sebesar 104,56 kg. Pengelolaan material buangan sulfida (waste dump adalah menerapkan model encapsulation in-pit disposal. Hal ini sangat efektif untuk mencegah terbentuknya air asam tambang. Material perlapisan yang digunakan adalah lempung (clay, karena mempunyai nilai permeabilitas yang sangat kecil yaitu sebesar 2,3148 x 10-9 m/det dan ketersediaannya mencukupi.   ABSTRACT Coal mining activity generally can generate negative impact to environment on mining location. One of the negative impact is contamination of acid mine drainage which able to destroy environment and ecosystem as water and soil. High potency source of acid mine drainage formed on coal mining location are water pond and waste dump. This aim of the research are control of acid mine drainage from water pond and prevention of acid mine drainage formed on the waste dump

  12. Chemical decontamination method for radioactive metal waste

    International Nuclear Information System (INIS)

    Onuma, Tsutomu; Tanaka, Akio; Shibuya, Sadao.

    1991-01-01

    When contaminants mainly composed of copper remained on the surface of stainless steel wastes sent from an electrolytic reduction as a first step are chemically decontaminated, metal wastes are discriminated to carbon steel wastes and stainless steel wastes. Then, the carbon steel wastes are applied only with the first step of immersing in a sulfuric acid solution, and stainless steel wastes are applied with a first step of immersing into a sulfuric acid solution for electrolytic reduction for a predetermined period of time and a second step of immersing into a liquid in which an oxidative metal salt is added to sulfuric acid. The decontamination liquid which is used for immersing the stainless steel wastes in the second step and the oxidation force of which is lowered is used as the sulfuric acid solution in the first step for the carbon steel wastes. In view of the above, the decontamination liquid of the second step can be utilized most effectively, enabling to greatly decrease the secondary wastes and to improve decontamination efficiency. (T.M.)

  13. Feed Materials Production Center Waste Management Plan

    International Nuclear Information System (INIS)

    Watts, R.E.; Allen, T.; Castle, S.A.; Hopper, J.P.; Oelrich, R.L.

    1986-01-01

    In the process of producing uranium metal products used in Department of Energy (DOE) defense programs at other DOE facilities, various types of wastes are generated at the Feed Materials Production Center (FMPC). Process wastes, both generated and stored, are discussed in the Waste Management Plan and include low-level radioactive waste (LLW), mixed hazardous/radioactive waste, and sanitary/industrial waste. Scrap metal waste and wastes requiring special remediation are also addressed in the Plan. The Waste Management Plan identifies the comprehensive programs developed to address safe storage and disposition of all wastes from past, present, and future operations at the FMPC. Waste streams discussed in this Plan are representative of the waste generated and waste types that concern worker and public health and safety. Budgets and schedules for implementation of waste disposition are also addressed. The waste streams receiving the largest amount of funding include LLW approved for shipment by DOE/ORO to the Nevada Test Site (NTS) (MgF 2 , slag leach filter cake, and neutralized raffinate); remedial action wastes (waste pits, K-65 silo waste); thorium; scrap metal (contaminated and noncontaminated ferrous and copper scrap); construction rubble and soil generated from decontamination and decommissioning of outdated facilities; and low-level wastes that will be handled through the Low-Level Waste Processing and Shipping System (LLWPSS). Waste Management milestones are also provided. The Waste Management Plan is divided into eight major sections: Introduction; Site Waste and Waste Generating Process; Strategy; Projects and Operations; Waste Stream Budgets; Milestones; Quality Assurance for Waste Management; and Environmental Monitoring Program

  14. Method for decontaminating radiation metal waste

    International Nuclear Information System (INIS)

    Onuma, Tsutomu; Tanaka, Akio; Akimoto, Hidetoshi

    1991-01-01

    This report describes a method for decontaminating radiation metal waste characterized by the following properties: in order to decontaminate radiation metal waste of various shapes produced by facilities involved with radioactive substances, non-complex shapes are decontaminated by electropolishing the materials in a neutral saline solution. Complex shapes are chemically decontaminated by means of an acid solution containing permanganic acid or an alkaline solution and a mineral acid solution. After neutralizing the solutions used for chemical decontamination, the radioactive material is separated and removed. Further, in the decontamination method for radioactive metal waste, a supernatant liquid is reused as the electrolyte in electropolishing decontamination. Permanganic ions (MnO 4 - ) are reduced to manganese dioxide (MnO 2 ) and deposited prior to neutralizing the solution used for chemical decontamination. Once manganese dioxide (MnO 2 ) has been separated and removed, it is re-used as the electrolyte in electropolishing decontamination by means of a process identical to the separation process for radioactive substances. 3 figs

  15. Microbial Diversity and Its Relationship to Physicochemical Characteristics of the Water in Two Extreme Acidic Pit Lakes from the Iberian Pyrite Belt (SW Spain.

    Directory of Open Access Journals (Sweden)

    Esther Santofimia

    Full Text Available The Iberian Pyrite Belt (IPB hosts one of the world's largest accumulations of acidic mine wastes and pit lakes. The mineralogical and textural characteristics of the IPB ores have favored the oxidation and dissolution of metallic sulfides, mainly pyrite, and the subsequent formation of acidic mining drainages. This work reports the physical properties, hydrogeochemical characteristics, and microbial diversity of two pit lakes located in the IPB. Both pit lakes are acidic and showed high concentrations of sulfate and dissolved metals. Concentrations of sulfate and heavy metals were higher in the Nuestra Señora del Carmen lake (NSC by one order of magnitude than in the Concepción (CN lake. The hydrochemical characteristics of NSC were typical of acid mine waters and can be compared with other acidic environments. When compared to other IPB acidic pit lakes, the superficial water of CN is more diluted than that of any of the others due, probably, to the strong influence of runoff water. Both pit lakes showed chemical and thermal stratification with well defined chemoclines. One particular characteristic of NSC is that it has developed a chemocline very close to the surface (2 m depth. Microbial community composition of the water column was analyzed by 16S and 18S rRNA gene cloning and sequencing. The microorganisms detected in NSC were characteristic of acid mine drainage (AMD, including iron oxidizing bacteria (Leptospirillum, Acidithiobacillus ferrooxidans and facultative iron reducing bacteria and archaea (Acidithiobacillus ferrooxidans, Acidiphilium, Actinobacteria, Acidimicrobiales, Ferroplasma detected in the bottom layer. Diversity in CN was higher than in NSC. Microorganisms known from AMD systems (Acidiphilium, Acidobacteria and Ferrovum and microorganisms never reported from AMD systems were identified. Taking into consideration the hydrochemical characteristics of these pit lakes and the spatial distribution of the identified

  16. Development of a method of heat treatment of metals in soaking pits in the bar-rolling shop of the Belarusian metallurgical works

    International Nuclear Information System (INIS)

    D'yachenko, Yu. V.; Ho Juituuan; Steblov, A.B.

    1995-01-01

    The problem of constructing a method for heat treatment of metals in soaking pits is considered and solved. Procedures of optimum heating and cooling of blanks are presented. Results of numerical calculations are given

  17. Recycling of metals from metal containing industrial wastes by means of plasma

    International Nuclear Information System (INIS)

    Burkhard, R.

    1995-01-01

    Recovery of metals from complex mixed wastes is a challenging task of modern material and waste management strategies. Thermal methods are an important tool in this respect. Plasma turned out to be particularly useful for treatment of complex or toxic wastes and residuals. In order to study the recycling parameters and behaviour of different metal containing wastes at reasonable costs, two pilot plasma plants have been used and metal containing, industrial wastes like spent Raney-Nickel catalysts, copper and aluminium drosses, MMC's, scrap, and others were investigated. The heart of the plasma equipment used is the Rotating Hearth (PRH) with a central base orifice. The hearth of the furnace rotates with a speed which prevents the melt from dripping. For pouring, the rotational speed is lowered, which allows the melt to be dripped into a mould. The RIF2 is equipped with a transferred plasma torch which can be operated up to 200 kW. The furnace is equipped with a secondary combustion chamber (SCC). The gases leaving the SCC go through a quench/scrubber. A powerful fan maintains underpressure in the whole system. Waste and additives can be fed through a nitrogen-purged port batchwise or with a screw feeder. The main components of the waste material investigated are nickel and aluminium in Raney-Nickel. The goal to recycle it is to produce NiFe-alloys for further use in the steel industry, or even NiAl-alloy for new catalyst production by using aluminium scrap as reducing and alloying element respectively. Aluminium dross occurs as an unavoidable by-product of all aluminium melting operations. It consists of metallic aluminium, oxides, nitrides, and salts. The separation of the aluminium phase from the oxides is the main task for recycling the aluminium. The general result is: recovery of metals out of complex mixed waste by using plasma rotating hearth technology and appropriate furnace modifications is feasible and ecological-economically interesting. (author) 147

  18. The Recovery of Zinc Heavy Metal from Industrial Liquid Waste

    International Nuclear Information System (INIS)

    Panggabean, Sahat M.

    2000-01-01

    It had been studied the recovery of zinc heavy metal from liquid waste of electroplating industry located at East Jakarta. The aim of this study was to minimize the waste arisen from industrial activities by taking out zinc metal in order to reused on-site. The method of recovery was two steps precipitation using NaOH reagent and pH variation. The first step of precipitation at pH optimum around 6 yielded iron metal. The second step at pH optimum around 10 yielded zinc metal. The zinc metal was taken out assessed to the possibility of reused at that fabric. By applying its, it will yield the volume reduction of sludge waste about 36.1% or 53.2% of zinc metal containing in the waste. It means the cost of waste treatment will be lower. Beside its, the effluent arisen from the method had fulfill the maximum limit and it allowed to release to the environment. (author)

  19. Separation of Metals From Spent Catalysts Waste by Bioleaching Process

    OpenAIRE

    Sirin Fairus, Tria Liliandini, M.Febrian, Ronny Kurniawan

    2010-01-01

    A kind of waste that hard to be treated is a metal containing solid waste. Leaching method is one thealternative waste treatment. But there still left an obstacle on this method, it is the difficulty to find theselective solvent for the type of certain metal that will separated. Bioleaching is one of the carry ablealternative waste treatments to overcome that obstacle. Bioleaching is a metal dissolving process orextraction from a sediment become dissolve form using microorganisms. On this met...

  20. Flow analysis of metals in a municipal solid waste management system

    International Nuclear Information System (INIS)

    Jung, C.H.; Matsuto, T.; Tanaka, N.

    2006-01-01

    This study aimed to identify the metal flow in a municipal solid waste (MSW) management system. Outputs of a resource recovery facility, refuse derived fuel (RDF) production facility, carbonization facility, plastics liquefaction facility, composting facility, and bio-gasification facility were analyzed for metal content and leaching concentration. In terms of metal content, bulky and incombustible waste had the highest values. Char from a carbonization facility, which treats household waste, had a higher metal content than MSW incinerator bottom ash. A leaching test revealed that Cd and Pb in char and Pb in RDF production residue exceeded the Japanese regulatory criteria for landfilling, so special attention should be paid to final disposal of these substances. By multiplying metal content and the generation rate of outputs, the metal content of input waste to each facility was estimated. For most metals except Cr, the total contribution ratio of paper/textile/plastics, bulky waste, and incombustible waste was over 80%. Approximately 30% of Cr originated from plastic packaging. Finally, several MSW management scenarios showed that most metals are transferred to landfills and the leaching potential of metals to the environment is quite small

  1. Markov Chain Models for the Stochastic Modeling of Pitting Corrosion

    OpenAIRE

    Valor, A.; Caleyo, F.; Alfonso, L.; Velázquez, J. C.; Hallen, J. M.

    2013-01-01

    The stochastic nature of pitting corrosion of metallic structures has been widely recognized. It is assumed that this kind of deterioration retains no memory of the past, so only the current state of the damage influences its future development. This characteristic allows pitting corrosion to be categorized as a Markov process. In this paper, two different models of pitting corrosion, developed using Markov chains, are presented. Firstly, a continuous-time, nonhomogeneous linear growth (pure ...

  2. Melting decontamination and free release of metal waste at Studsvik RadWaste Co. in Sweden

    International Nuclear Information System (INIS)

    Kawatsuma, Shinji; Ishikawa, Keiji; Matsubara, Tatsuo; Donomae, Yasushi; Imagawa, Yasuhiro

    2006-01-01

    The Studsvik RadWaste Co. in Sweden was visited on August 29, 2005 by members of radioactive waste and decommissioning subgroup of central safety task force in old Japan Nuclear Cycle Development Institute as 'Overseas investigation'. The visit afforded us the chance to survey melting and decontaminating of metallic waste in this company and the status of free release. Domestic and foreign radioactive metallic waste is accepted in this company after 1987, and the majority of the decontaminated waste have been released freely. In the background of the big effort of this company and the strong leadership of the regulator (SSI: Swedish radiation protection Authority), prosperous operation was able to have been achieved. This survey was done based on 'Free release of radioactive metallic waste in Europe: the free release experience for 17 years at Studsvik RadWaste Co. in Sweden' by Dr. J. Lorenzen. (author)

  3. Crevice corrosion ampersand pitting of high-level waste containers: integration of deterministic ampersand probabilistic models

    International Nuclear Information System (INIS)

    Farmer, J.C.; McCright, R.D.

    1997-01-01

    A key component of the Engineered Barrier System (EBS) being designed for containment of spent-fuel and high-level waste at the proposed geological repository at Yucca Mountain, Nevada is a two-layer canister. In this particular design, the inner barrier is made of a corrosion resistant material (CRM) such as Alloy 625 or C-22, while the outer barrier is made of a corrosion-allowance material (CAM) such as carbon steel or Monel 400. An integrated predictive model is being developed to account for the effects of localized environmental conditions in the CRM-CAM crevice on the initiation and propagation of pits through the CRM

  4. CREVICE CORROSION and PITTING OF HIGH-LEVEL WASTE CONTAINERS: INTEGRATION OF DETERMINISTIC and PROBABILISTIC MODELS

    International Nuclear Information System (INIS)

    JOSEPH C. FARMER AND R. DANIEL MCCRIGHT

    1997-01-01

    A key component of the Engineered Barrier System (EBS) being designed for containment of spent-fuel and high-level waste at the proposed geological repository at Yucca Mountain, Nevada is a two-layer canister. In this particular design, the inner barrier is made of a corrosion resistant material (CRM) such as Alloy 625 or C-22, while the outer barrier is made of a corrosion-allowance material (CAM) such as carbon steel or Monel 400. An integrated predictive model is being developed to account for the effects of localized environmental conditions in the CRM-CAM crevice on the initiation and propagation of pits through the CRM

  5. Development and investigation of a pollution control pit for treatment of stormwater from metal roofs and traffic areas.

    Science.gov (United States)

    Dierkes, C; Göbel, P; Lohmann, M; Coldewey, W G

    2006-01-01

    Source control by on-site retention and infiltration of stormwater is a sustainable and proven alternative to classical drainage methods. Unfortunately, sedimentary particles and pollutants from drained surfaces cause clogging and endanger soil and groundwater during long-term operation of infiltration devices. German water authorities recommend the use of infiltration devices, such as swales or swale-trench-systems. Direct infiltration by underground facilities, such as pipes, trenches or sinks, without pretreatment of runoff is generally not permitted. Problems occur with runoff from metal roofs, traffic areas and industrial sites. However, due to site limitations, underground systems are often the only feasible option. To overcome this situation, a pollution control pit was developed with a hydrodynamic separator and a multistage filter made of coated porous concrete. The system treats runoff at source and protects soil, groundwater and receiving waterways. Typically, more than 90% of the pollutants such as sedimentary particles, hydrocarbons and heavy metals can be removed. Filters have been developed to treat even higher polluted stormwater loads from metal roofs and industrial sites. The treatment process is based on sedimentation, filtration, adsorption and chemical precipitation. Sediments are trapped in a special chamber within the pit and can be removed easily. Other pollutants are captured in the concrete filter upstream of the sediment separator chamber. Filters can be easily replaced.

  6. Fast Track Characterization of Highly Radioactive Waste Pits Combining Off-the-Shelf Robotics with Innovative Investigation Protocols

    International Nuclear Information System (INIS)

    Chabeuf, Jean-Michel; Boya, Didier

    2008-01-01

    The investigation and characterization of radioactive waste pits and effluent storage tanks represents a substantial and challenging step in the overall decommissioning programme launched by AREVA NC in 1998 on the site of Marcoule on behalf of the French Atomic Energy commission. Physical ,radiological and regulatory constraints, combined with a tight schedule, have lead our teams to use proven conventional instrumentation and robotics in innovative configurations . One such investigation, conducted on a particularly challenging radioactive effluent storage pit, is described below. The 'H' pit is a stainless steel clad concrete cavity, located in the second basement of the de-cladding building of Marcoule site. It was used for forty years as buffer storage for high activity effluents and has a length of 5 meters, a width of 3 meters , a height of 2.5 meters, and is topped by lead plates over 5 cm thick and The bottom of the cavity is covered with a layer of mud containing mainly graphite, diatoms and resins. The mud level ranges from about 20 centimeters to over 50 centimeters. The overall mud volume is around 2.4 cubic meters. Ambient dose rates above the lead plates exceed 10 mSv/h. The main purpose of our investigation was to characterize the muds for future recovery and conditioning prior to decontaminating the pit. The history of the pit together with the varying mud altimetry lead us to believe that sedimentation had probably occurred throughout the years. We thus decided to combine dose rate measurements using IF104 probes, gamma spectroscopy with CdTe probes and sample collections at different depths to ensure the representativeness and full characterization of the muds. Poor access, ambient dose rates have lead us to conceive a robotic arm, mounted on an shaft which can be modified to fit a wide range of pits and tanks. Custom built robotic tools with maximum manoeuvrability generally involve costs and delays far exceeding our purposes. SIT, a French

  7. Method of electrolytically decontaminating of radioactive metal wastes

    International Nuclear Information System (INIS)

    Oonuma, Tsutomu; Tanaka, Akio; Yamadera, Toshio.

    1985-01-01

    Purpose: To significantly reduce the volume of secondary wastes by separating from electrolytes metal ions containing radioactive metal ions dissolved therein in the form of elemental metals of a reduced volume with ease, as well as regenerating the electrolytes for re-use. Method: Contaminated portions at the surface of the radioactive metal wastes are dissolved in electrolytes and, when the metal ion concentration in the electrolytes reaches a predetermined level, the electrolytes are introduced to an acid recovery step and an electrodeposition step. The recovered acid is re-used as the electrolytes, while dissolved metal ions containing radioactive metal ions are deposited as elemental metals in the electrodeposition step. The electrolytes usable herein include those acids easily forming stable complex compounds with the metals or those not forming hydroxides of the contaminated metals. Combination of sodium sulfate and sulfuric acid, sodium chloride and hydrochloride or the like is preferred. (Kamimura, M.)

  8. The Microstructure and Pitting Resistance of Weld Joints of 2205 Duplex Stainless Steel

    Science.gov (United States)

    Wu, Mingfang; Liu, Fei; Pu, Juan; Anderson, Neil E.; Li, Leijun; Liu, Dashuang

    2017-11-01

    2205 duplex stainless steel (DSS) was welded by submerged arc welding. The effects of both heat input and groove type on the ferrite/austenite ratio and elemental diffusion of weld joints were investigated. The relationships among welding joint preparation, ferrite/austenite ratio, elemental diffusion, and pitting corrosion resistance of weld joints were analyzed. When the Ni content of the weld wire deposit was at minimum 2-4% higher than that of 2205 DSS base metal, the desired ratio of ferrite/austenite and elemental partitioning between the austenite and ferrite phases were obtained. While the pitting sensitivity of weld metal was higher than that of base metal, the self-healing capability of the passive film of weld metal was better than that of the base metal when a single V-type groove was used. Furthermore, the heat input should be carefully controlled since pitting corrosion occurred readily in the coarse-grained heat-affected zone near the fusion line of welded joints.

  9. Mining Waste Classification and Quantity of Non-Metal Minesin Slovenia

    Directory of Open Access Journals (Sweden)

    Ana Burger

    2007-06-01

    Full Text Available Mining is an important human activity that creates wealth and supplies materials for maintaining standard of living and further human development. However, mining has also negative impacts on the environment and society. One of them is the production of mining waste throughout the entire mining cycle, in particular in the mine development and operation /production stage.Due to the EU Directive 2006/21/EC on the management of waste from the extractive industries and its implementation in Member state, estimation on quality and quantity of mining waste from active non-metal mines in Slovenia was carried out. In the selected mines mining and processing was closely examined. With material flow analysis quantity and characteristics of mining waste were defined for several mines of different commodities.Data on mining waste were afterwards generalized in order to get an overall country evaluation on mining waste “production” of non-metal mines.Mining waste as a result of mining and beneficiation processes in non-metal mines of Slovenia is either inert or non-hazardous. Most of the mining waste is used for mine reclamation running simultaneously with the production phase. The largest amounts of mining waste per unit produced are created in dimension stone industry. Since the dimensionstone production is small, the waste amount is negligible. Large quantities of mining waste are produced in crushed stone and, sand and gravel operations, because aggregate production is pretty large with regard to other non-metals production in Slovenia. We can therefore conclude that large quantities of mining waste from non-metal mines, which are mostly used in reclamation and for side products, do not represent danger to the environment.

  10. Processing method of radioactive metal wastes

    International Nuclear Information System (INIS)

    Uetake, Naoto; Urata, Megumu; Sato, Masao.

    1985-01-01

    Purpose: To reduce the volume and increase the density of radioactive metal wastes easily while preventing scattering of radioactivity and process them into suitable form to storage and treatment. Method: Metal wastes mainly composed of zirconium are discharged from nuclear power plants or fuel re-processing plants, and these metals such as zirconium and titanium vigorously react with hydrogen and rapidly diffuse as hydrides. Since the hydrides are extremely brittle and can be pulverized easily, they can be volume-reduced. However, since metal hydrides have no ductility, dehydrogenation is applied for the molding fabrication in view of the subsequent storage and processing. The dehydrogenation is easy like the hydrogenation and fine metal pieces can be molded in a small compression device. For the dehydrogenation, a temperature is slightly increased as compared with that in the hydrogenation, pressure is reduced through the vacuum evacuation system and the removed hydrogen is purified for reuse. The upper limit for the temperature of the hydrogenation is 680 0 C in order to prevent the scttering of radioactivity. (Kamimura, M.)

  11. DOE mixed waste metals partition in a rotary kiln wet off-gas system

    International Nuclear Information System (INIS)

    Burns, D.B.; Looper, M.G.

    1994-01-01

    In 1996, the Savannah River Site plans to begin operation of the Consolidated Incineration Facility (CIF) to treat solid and liquid RCRA hazardous and mixed wastes. Test burns were conducted using surrogate CIF wastes spiked with hazardous metals and organics. The partition of metals between the kiln bottom ash, scrubber blowdown solution, and stack gas was measured as a function of kiln temperature, waste chloride content, and waste form (liquid or solid). Three waste simulants were used in these tests, a high and low chloride solid waste mix (paper, plastic, latex, PVC), and a liquid waste mix (benzene and chlorobenzene). An aqueous solution containing: antimony, arsenic, barium, cadmium, chromium, lead, mercury, nickel, silver, and thallium was added to the waste to determine metals fate under various combustion conditions. Test results were used to divide the metals into three general groups, volatile, semi-volatile, and nonvolatile metals. Mercury was the only volatile metal. No mercury remained in the kiln bottom ash under any incineration condition. Lead, cadmium, thallium, and silver exhibited semi-volatile behavior. The partition between the kiln ash, blowdown, and stack gas depended on incineration conditions. Chromium, nickel, barium, antimony, and arsenic exhibited nonvolatile behavior, with greater than 90 wt % of the metal remaining in the kiln bottom ash. Incineration temperature had a significant effect on the partition of volatile and semi-volatile metals, and no effect on nonvolatile metal partition. As incineration temperatures were increased, the fraction of metal leaving the kiln increased. Three metals, lead, cadmium, and mercury showed a relationship between chloride concentration in the waste and metals partition. Increasing the concentration of chlorides in the waste or burning liquid waste versus solid waste resulted in a larger fraction of metal exiting the kiln

  12. Characteristics of Cement Solidification of Metal Hydroxide Waste

    Directory of Open Access Journals (Sweden)

    Dae-Seo Koo

    2017-02-01

    Full Text Available To perform the permanent disposal of metal hydroxide waste from electro-kinetic decontamination, it is necessary to secure the technology for its solidification. The integrity tests on the fabricated solidification should also meet the criteria of the Korea Radioactive Waste Agency. We carried out the solidification of metal hydroxide waste using cement solidification. The integrity tests such as the compressive strength, immersion, leach, and irradiation tests on the fabricated cement solidifications were performed. It was also confirmed that these requirements of the criteria of Korea Radioactive Waste Agency on these cement solidifications were met. The microstructures of all the cement solidifications were analyzed and discussed.

  13. Characteristics of cement solidification of metal hydroxide waste

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Dae Seo; Sung, Hyun Hee; Kim, Seung Soo; Kim, Gye Nam; Choi, Jong Won [Dept. of Decontemination Decommission Technology Development, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2017-02-15

    To perform the permanent disposal of metal hydroxide waste from electro-kinetic decontamination, it is necessary to secure the technology for its solidification. The integrity tests on the fabricated solidification should also meet the criteria of the Korea Radioactive Waste Agency. We carried out the solidification of metal hydroxide waste using cement solidification. The integrity tests such as the compressive strength, immersion, leach, and irradiation tests on the fabricated cement solidifications were performed. It was also confirmed that these requirements of the criteria of Korea Radioactive Waste Agency on these cement solidifications were met. The microstructures of all the cement solidifications were analyzed and discussed.

  14. Radioactive waste processing facility and underground processing method for radioactive wastes using the facility

    International Nuclear Information System (INIS)

    Hasegawa, Yasuyuki

    1998-01-01

    There are disposed a communication pit laterally extended in an underground base rock, an access pit extended from the ground surface to the communication pit, discarding pits laterally extended at a plurality of longitudinal positions of the communication pit and layered buffer materials for keeping a radioactive waste-sealing container at substantially the center of the discarding pit. The layered buffer material comprises fan-shaped buffer blocks divided so that the axial end faces of inner and outer layers are displaced with each other in the axial direction of the discarding pit and so that the circumferential end faces of the inner and the outer layers are circumferentially displaced with each other. Even if the base lock should move, the layered buffer material reduces the propagation of the movement to the radioactive waste-sealing vessel thereby enabling to enhance supporting strength. (N.H.)

  15. Heavy metal vaporization and abatement during thermal treatment of modified wastes

    International Nuclear Information System (INIS)

    Rio, S.; Verwilghen, C.; Ramaroson, J.; Nzihou, A.; Sharrock, P.

    2007-01-01

    This study examines the vaporization percentage and partitioning of heavy metals Cd, Pb and Zn during thermal treatment of wastes with added PVC, heavy metals or phosphate, and the efficiency of sorbents for removal of these metallic compounds in flue gas of an industrial solid waste incinerator. Firstly, vaporization experiments were carried out to determine the behavior of heavy metals during combustion under various conditions (type of waste, temperature, presence of chloride or phosphate ...). The experimental results show relatively high vaporization percentage of metallic compounds within fly ash and limestone matrix while heavy metals within sediments treated with phosphoric acid are less volatile. Vaporization of metals increases with increasing temperature and with chloride addition. The thermal behavior of the selected heavy metals and their removal by sorbents (sodium bicarbonate, activated carbon) was also studied in an industrial solid waste incinerator. These pilot scale experiments confirm that heavy metals are concentrated in fly ashes and cyclone residues, thus effectively controlling their release to the atmosphere

  16. A New Algorithm for Determining Ultimate Pit Limits Based on Network Optimization

    OpenAIRE

    Ali Asghar Khodayari

    2013-01-01

    One of the main concerns of the mining industry is to determine ultimate pit limits. Final pit is a collection of blocks, which can be removed with maximum profit while following restrictions on the slope of the mine’s walls. The size, location and final shape of an open-pit are very important in designing the location of waste dumps, stockpiles, processing plants, access roads and other surface facilities as well as in developing a production program. There are numerous methods for designing...

  17. Pitting corrosion of copper. Further model studies

    International Nuclear Information System (INIS)

    Taxen, C.

    2002-08-01

    The work presented in this report is a continuation and expansion of a previous study. The aim of the work is to provide background information about pitting corrosion of copper for a safety analysis of copper canisters for final deposition of radioactive waste. A mathematical model for the propagation of corrosion pits is used to estimate the conditions required for stationary propagation of a localised anodic corrosion process. The model uses equilibrium data for copper and its corrosion products and parameters for the aqueous mass transport of dissolved species. In the present work we have, in the model, used a more extensive set of aqueous and solid compounds and equilibrium data from a different source. The potential dependence of pitting in waters with different compositions is studied in greater detail. More waters have been studied and single parameter variations in the composition of the water have been studied over wider ranges of concentration. The conclusions drawn in the previous study are not contradicted by the present results. However, the combined effect of potential and water composition on the possibility of pitting corrosion is more complex than was realised. In the previous study we found what seemed to be a continuous aggravation of a pitting situation by increasing potentials. The present results indicate that pitting corrosion can take place only over a certain potential range and that there is an upper potential limit for pitting as well as a lower. A sensitivity analysis indicates that the model gives meaningful predictions of the minimum pitting potential also when relatively large errors in the input parameters are allowed for

  18. Anaerobic bioleaching of metals from waste activated sludge

    International Nuclear Information System (INIS)

    Meulepas, Roel J.W.; Gonzalez-Gil, Graciela; Teshager, Fitfety Melese; Witharana, Ayoma; Saikaly, Pascal E.; Lens, Piet N.L.

    2015-01-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342 μg g −1 of copper, 487 μg g −1 of lead, 793 μg g −1 of zinc, 27 μg g −1 of nickel and 2.3 μg g −1 of cadmium. During the anaerobic acidification of 3 g dry weight L −1 waste activated sludge, 80–85% of the copper, 66–69% of the lead, 87% of the zinc, 94–99% of the nickel and 73–83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead. - Highlights: • Heavy metals were leached during anaerobic acidification of waste activated sludge. • The process does not require the addition of chelating or oxidizing agents. • The metal leaching efficiencies (66 to 99%) were comparable to chemical leaching. • The produced leachate may be used for metal recovery and biogas production. • The produced digested sludge may be used as soil conditioner

  19. Testing of intergranular and pitting corrosion in sensitized welded joints of austenitic stainless steel

    Directory of Open Access Journals (Sweden)

    Bore V. Jegdic

    2017-06-01

    Full Text Available Pitting corrosion resistance and intergranular corrosion of the austenitic stainless steel X5Cr Ni18-10 were tested on the base metal, heat affected zone and weld metal. Testing of pitting corrosion was performed by the potentiodynamic polarization method, while testing of intergranular corrosion was performed by the method of electrochemical potentiokinetic reactivation with double loop. The base metal was completely resistant to intergranular corrosion, while the heat affected zone showed a slight susceptibility to intergranular corrosion. Indicators of pitting corrosion resistance for the weld metal and the base metal were very similar, but their values are significantly higher than the values for the heat affected zone. This was caused by reduction of the chromium concentration in the grain boundary areas in the heat affected zone, even though the carbon content in the examined stainless steel is low (0.04 wt. % C.

  20. Markov Chain Models for the Stochastic Modeling of Pitting Corrosion

    Directory of Open Access Journals (Sweden)

    A. Valor

    2013-01-01

    Full Text Available The stochastic nature of pitting corrosion of metallic structures has been widely recognized. It is assumed that this kind of deterioration retains no memory of the past, so only the current state of the damage influences its future development. This characteristic allows pitting corrosion to be categorized as a Markov process. In this paper, two different models of pitting corrosion, developed using Markov chains, are presented. Firstly, a continuous-time, nonhomogeneous linear growth (pure birth Markov process is used to model external pitting corrosion in underground pipelines. A closed-form solution of the system of Kolmogorov's forward equations is used to describe the transition probability function in a discrete pit depth space. The transition probability function is identified by correlating the stochastic pit depth mean with the empirical deterministic mean. In the second model, the distribution of maximum pit depths in a pitting experiment is successfully modeled after the combination of two stochastic processes: pit initiation and pit growth. Pit generation is modeled as a nonhomogeneous Poisson process, in which induction time is simulated as the realization of a Weibull process. Pit growth is simulated using a nonhomogeneous Markov process. An analytical solution of Kolmogorov's system of equations is also found for the transition probabilities from the first Markov state. Extreme value statistics is employed to find the distribution of maximum pit depths.

  1. Review of metal-matrix encapsulation of solidified radioactive high-level waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-05-01

    Literature describing previous and current work on the encapsulation of solidified high-level waste forms in a metal matrix was reviewed. Encapsulation of either stabilized calcine pellets or glass beads in alloys by casting techniques was concluded to be the most developed and direct approach to fabricating solid metal-matrix waste forms. Further characterizations of the physical and chemical properties of metal-matrix waste forms are still needed to assess the net attributes of metal-encapsulation alternatives. Steady-state heat transfer properties of waste canisters in air and water environments were calculated for four reference waste forms: (1) calcine, (2) glass monoliths, (3) metal-encapsulated calcine, and (4) metal-encapsulated glass beads. A set of criteria for the maximum allowable canister centerline and surface temperatures and heat generation rates per canister at the time of shipment to a Federal repository was assumed, and comparisons were made between canisters of these reference waste forms of the shortest time after reactor discharge that canisters could be filled and the subsequent ''interim'' storage times prior to shipment to a Federal repository for various canister diameters and waste ages. A reference conceptual flowsheet based on existing or developing technology for encapsulation of stabilized calcine pellets is discussed. Conclusions and recommendations are presented

  2. Development of technique for quantifying gamma emitters in metal waste. New technique of precise and automatic measurements for confirmation of clearance level of metal waste

    International Nuclear Information System (INIS)

    Hattori, Takatoshi

    2002-01-01

    A New technique of precise and automatic measurements of gamma emitters in metal waste has been developed using 3D non-contact shape measurement and monte-carlo calculation techniques in order to confirm that specific radioactivity level of metal waste satisfies the clearance level and furthermore the surface contamination level of the metal waste is below the legal standard level. The technique can give a calibration factor every measurement target automatically and realize an automatic correction for reduction of background count rate in gamma measurements due to self-shield effect of the measurement target. The accuracy of the present method has been made clear using mock-metal wastes with various types of shape, number and size. Assuming the goal of the detection limit for practical use is 25OBq in radioactivity, a concept of the practical gamma monitor has been designed so as to be able to confirm both the clearance level and surface contamination level simultaneously and to cope with the metal waste at a speed of 2-10 ton a day. (author)

  3. Inside report on arrangement progress of an open-air pit for tools and materials of Plutonium Fuel Center, JNC

    International Nuclear Information System (INIS)

    Ohmura, Kenji; Sato, Shunichi; Gunji, Yasutoshi; Sawayama, Takeo; Nogami, Tetsuya; Matsuno, Kazuya; Tominaga, Setsuo; Osawa, Takayasu

    1999-03-01

    In the course of arranging the wasted tools and materials in the open-air pit (B-pit) of Plutonium Fuel Center, JNC, a radioactive contamination occurred on June 25, 1998, on working clothes of an operator. The B-pit was immediately set up as a temporarily radiation-controlled area and the necessary works such as disposing contaminated wastes, decontamination and surface coatings as well as cleaning have been finished on February 2, 1999. The present report describes the main procedure of actual operations, a possible cause of the contamination, and the resulting wastes from the present work amounting to about 250 drums. (Ohno, S.)

  4. Geochemical atlas of Radovish and the environs and the distribution of heavy metals in the air

    International Nuclear Information System (INIS)

    Stafilov, Trajche; Bacheva, Katerina; Boev, Blazho; Shajn, Robert; Balabanova, Biljana

    2010-01-01

    Mining activities, ore processing and processing of waste are potential emitters of heavy metals in air. As more important are mining activities on surface excavation of ore due to the large number of direct polluting factors that are difficult to control and manage. Special emphasis is given to the organization of the pit (road movement of dampers carrying ore waste), waste management (ore and flotation tailings) as well as the frequency of explosions for excavation of mining minerals. One of the major emission sources of some metals in the eastern part of the R. Macedonia is Buchim copper mine and flotation, near the town of Radovish. The mine and plant for the preparation of ore are in function from the late seventies of the last century. Ore excavation is from open pit and the ore tailings are stored in the open, in mine vicinity. The produced copper ore from the mine is processed in the flotation tailings are separated, disposed of and deposited on a dump site in an adjacent valley near the village Topolnica.

  5. Pitting by corrosion in aluminium and Al-6201 alloy

    International Nuclear Information System (INIS)

    Vera, R.; Schrebler, R.; Layana, G.; Orellana, F.; Olguin, A.

    1998-01-01

    The susceptibility of pure aluminum 6201 alloy to pitting was investigated in sodium chloride solutions through determination of the corrosion, repassivation and pitting potentials. Potentiodynamic polarization including scratching techniques were employed being also determined the type and relative amount of corrosion damage to the metals. The morphology of the attach was determined using scanning electrons microscopy (SEM). The results showed a similar performance for aluminum 6201 alloy and aluminum. It was also observed that an increase in chloride concentration resulted in a decrease in the corrosion, pitting and repassivation potentials of both materials. (Author) 19 refs

  6. Anaerobic bioleaching of metals from waste activated sludge

    Energy Technology Data Exchange (ETDEWEB)

    Meulepas, Roel J.W., E-mail: roel.meulepas@wetsus.nl [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); Gonzalez-Gil, Graciela [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal 13955-69000 (Saudi Arabia); Teshager, Fitfety Melese; Witharana, Ayoma [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands); Saikaly, Pascal E. [King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal 13955-69000 (Saudi Arabia); Lens, Piet N.L. [UNESCO-IHE, Westvest 7, 2611 AX Delft (Netherlands)

    2015-05-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342 μg g{sup −1} of copper, 487 μg g{sup −1} of lead, 793 μg g{sup −1} of zinc, 27 μg g{sup −1} of nickel and 2.3 μg g{sup −1} of cadmium. During the anaerobic acidification of 3 g{sub dry} {sub weight} L{sup −1} waste activated sludge, 80–85% of the copper, 66–69% of the lead, 87% of the zinc, 94–99% of the nickel and 73–83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead. - Highlights: • Heavy metals were leached during anaerobic acidification of waste activated sludge. • The process does not require the addition of chelating or oxidizing agents. • The metal leaching efficiencies (66 to 99%) were comparable to chemical leaching. • The produced leachate may be used for metal recovery and biogas production. • The produced digested sludge may be used as soil conditioner.

  7. Decomposition of vegetation growing on metal mine waste

    Energy Technology Data Exchange (ETDEWEB)

    Williams, S T; McNeilly, T; Wellington, E M.H.

    1977-01-01

    Aspects of the decomposition of metal tolerant vegetation growing on mine waste containing high concentrations of lead and zinc were studied and compared with those on an adjacent uncontaminated site. High concentrations of Pb and, to a lesser extent, Zn, accumulated in metal-tolerant grass. Retarded decomposition of this vegetation as compared with that on the uncontaminated site was indicated by a greater accumulation of litter, less humus formation, reduced soil urease activity and smaller microbial and microfaunal populations. Some evidence for increased metal tolerance in microbes from the mine waste was obtained. Concentrations of lead tolerated under laboratory conditions were much lower than those extracted from the mine waste and its vegetation, probably due to the lack of an accurate method for assessing the availability of lead in soil and vegetation.

  8. BPEO/BPM in recycling of low level waste metal in the UK - 16210

    International Nuclear Information System (INIS)

    Dodd, Kevin; Robinson, Joe; Lindberg, Maria

    2009-01-01

    Best Practicable Environmental Option (BPEO) and Best Practicable Means (BPM) are concepts well established in the nuclear industry to help guide and inform waste management decision making. The recycling of contaminated metal waste in the UK is not well established, with the majority of waste disposed of at the Low Level Waste Repository (LLWR) at Drigg. This paper presents an overview of the Strategic BPEO study completed by Studsvik examining the options for low level metal waste management and a subsequent BPM study completed in support of a proposed metals recycling service. The environmental benefits of recycling metals overseas is further examined through the application of life cycle analysis to the metals recycling process. The methodologies used for both studies are discussed and the findings of these studies presented. These indicate that recycling contaminated metal is the preferred option, using overseas facilities until UK facilities are available. The BPM for metals recycling is discussed in detail and indicates that a tool box for processing metal waste is required to ensure BPM is applied on a case by case basis. This is supported by effective management of waste transport and waste acceptance criteria. Whilst the transport of contaminated metal overseas for treatment adds to the environmental burden of metals recycling, this when compared with the production of virgin metal, is shown to remain beneficial. The results of the Studsvik studies demonstrate the benefits of recycling metals, the options available for such a service and challenges that remain. (authors)

  9. Characterizing the environmental impact of metals in construction and demolition waste.

    Science.gov (United States)

    Yu, Danfeng; Duan, Huabo; Song, Qingbin; Li, Xiaoyue; Zhang, Hao; Zhang, Hui; Liu, Yicheng; Shen, Weijun; Wang, Jinben

    2018-05-01

    Large quantities of construction and demolition (C&D) waste are generated in China every year, but their potential environmental impacts on the surrounding areas are rarely assessed. This study focuses on metals contained in C&D waste, characterizing the metal concentrations and their related environmental risks. C&D waste samples were collected in Shenzhen City, China, from building demolition sites, renovation areas undergoing refurbishment, landfill sites, and recycling companies (all located in Shenzhen city) that produce recycled aggregate, in order to identify pollution levels of the metals As, Cd, Cr, Cu, Pb, Ni, and Zn. The results showed that (1) the metal concentrations in most demolition and renovation waste samples were below the soil environmental quality standard for agricultural purposes (SQ-Agr.) in China; (2) Cd, Cu, and Zn led to relatively higher environmental risks than other metals, especially for Zn (DM5 tile sample, 360 mg/kg; R4 tile sample, 281 mg/kg); (3) non-inert C&D waste such as wall insulation and foamed plastic had high concentrations of As and Cd, so that these materials required special attention for sound waste management; and (4) C&D waste collected from landfill sites had higher concentrations of Cd and Cu than did waste collected from demolition and refurbishment sites.

  10. The Solid Waste Transfer Pit an FFTF [Fast Flux Test Facility] station for fuel and reflector transfer

    International Nuclear Information System (INIS)

    Milewski, A.J.; Thomson, J.D.

    1985-01-01

    This paper describes the design aspects of a proposed FFTF facility called the Solid Waste Transfer Pit (SWTP). This new facility will be used as a transfer station for reflectors and/or low decay heat fuel assemblies when movement from the Fuel Storage Facility for sodium removal and subsequent reprocessing is to be accomplished. The SWTP utilizes a shielded cell cover with an integral manually-operated gate valve for top loading of a transfer vessel. The cost-effective design discussed herein provides a practical approach using state-of-the-art concepts while assuring safe and reliable operation

  11. Methods for recovering metals from electronic waste, and related systems

    Science.gov (United States)

    Lister, Tedd E; Parkman, Jacob A; Diaz Aldana, Luis A; Clark, Gemma; Dufek, Eric J; Keller, Philip

    2017-10-03

    A method of recovering metals from electronic waste comprises providing a powder comprising electronic waste in at least a first reactor and a second reactor and providing an electrolyte comprising at least ferric ions in an electrochemical cell in fluid communication with the first reactor and the second reactor. The method further includes contacting the powders within the first reactor and the second reactor with the electrolyte to dissolve at least one base metal from each reactor into the electrolyte and reduce at least some of the ferric ions to ferrous ions. The ferrous ions are oxidized at an anode of the electrochemical cell to regenerate the ferric ions. The powder within the second reactor comprises a higher weight percent of the at least one base metal than the powder in the first reactor. Additional methods of recovering metals from electronic waste are also described, as well as an apparatus of recovering metals from electronic waste.

  12. Bio-extraction of precious metals from urban solid waste

    Science.gov (United States)

    Das, Subhabrata; Natarajan, Gayathri; Ting, Yen-Peng

    2017-01-01

    Reduced product lifecycle and increasing demand for electronic devices have resulted in the generation of huge volumes of electronic waste (e-waste). E-wastes contain high concentrations of toxic heavy metals, which have detrimental effects on health and the environment. However, e-wastes also contain significant concentrations of precious metals such as gold, silver and palladium, which can be a major driving force for recycling of urban waste. Cyanogenic bacteria such as Chromobacterium violaceum generate cyanide as a secondary metabolite which mobilizes gold into solution via a soluble gold-cyanide complex. However, compared to conventional technology for metal recovery, this approach is not effective, owing largely to the low concentration of lixiviants produced by the bacteria. To overcome the challenges of bioleaching of gold from e-waste, several strategies were adopted to enhance gold recovery rates. These included (i) pretreatment of e-waste to remove competing metal ions, (ii) mutation to adapt the bacteria to high pH environment, (iii) metabolic engineering to produce higher cyanide lixiviant, and (iv) spent medium leaching with adjusted initial pH. Compared to 7.1 % recovery by the wild type bacteria, these strategies achieved gold recoveries of 11.3%, 22.5%, 30% and 30% respectively at 0.5% w/v pulp density respectively. Bioleached gold was finally mineralized and precipitated as gold nanoparticles using the bacterium Delftia acidovorans. This study demonstrates the potential for enhancement of biocyanide production and gold recovery from electronic waste through different strategies, and extraction of solid gold from bioleached leachate.

  13. Modeling and management of pit lake water chemistry 1: Theory

    International Nuclear Information System (INIS)

    Castendyk, D.N.; Eary, L.E.; Balistrieri, L.S.

    2015-01-01

    Highlights: • Review of pit lake literature in the context of pit lake predictions. • Review of approaches used to predict pit wall-rock runoff and leachate. • Review of approaches used to generate a pit lake water balance. • Review of approaches used to generate a hydrodynamic prediction. • Review of approaches used to generate a geochemical prediction of a future pit lake. - Abstract: Pit lakes are permanent hydrologic/landscape features that can result from open pit mining for metals, coal, uranium, diamonds, oil sands, and aggregates. Risks associated with pit lakes include local and regional impacts to water quality and related impacts to aquatic and terrestrial ecosystems. Stakeholders rely on predictive models of water chemistry to prepare for and manage these risks. This paper is the first of a two part series on the modeling and management of pit lakes. Herein, we review approaches that have been used to quantify wall-rock runoff geochemistry, wall-rock leachate geochemistry, pit lake water balance, pit lake limnology (i.e. extent of vertical mixing), and pit lake water quality, and conclude with guidance on the application of models within the mine life cycle. The purpose of this paper is to better prepare stakeholders, including future modelers, mine managers, consultants, permitting agencies, land management agencies, regulators, research scientists, academics, and other interested parties, for the challenges of predicting and managing future pit lakes in un-mined areas

  14. Use of overburden rocks from open-pit coal mines and waste coals of Western Siberia for ceramic brick production with a defect-free structure

    Science.gov (United States)

    Stolboushkin, A. Yu; Ivanov, A. I.; Storozhenko, G. I.; Syromyasov, V. A.; Akst, D. V.

    2017-09-01

    The rational technology for the production of ceramic bricks with a defect-free structure from coal mining and processing wastes was developed. The results of comparison of physical and mechanical properties and the structure of ceramic bricks manufactured from overburden rocks and waste coal with traditional for semi-dry pressing mass preparation and according to the developed method are given. It was established that a homogeneous, defect-free brick texture obtained from overburden rocks of open-pit mines and waste coal improves the quality of ceramic wall materials produced by the method of compression molding by more than 1.5 times compared to the brick with a traditional mass preparation.

  15. In situ EC-AFM study of the effect of nanocrystals on the passivation and pit initiation in an Al-based metallic glass

    International Nuclear Information System (INIS)

    Zhang, S.D.; Liu, Z.W.; Wang, Z.M.; Wang, J.Q.

    2014-01-01

    Highlights: • The nanoscale corrosion on Al-rich glass was characterised by in situ EC-AFM. • The nanocrystals were identified from amorphous matrix by tapping mode AFM. • The formation of corrosion products is associated with the galvanic coupling. • The nanocrystals changed the local structure and component of the passive film. - Abstract: The effect of nanocrystals on pit initiation in metallic glasses is an unresolved issue. The passive film formation and pit initiation in the Al–Ni–Ce metallic glass were investigated using in situ electrochemical atomic force microscope (EC-AFM). The α-Al nanophases were identified from the amorphous matrix based upon the phase imaging in the tapping mode AFM. In the early stage of the passive film formation, the corrosion products Al(OH) 3 formed on the α-Al nanoparticles due to the galvanic coupling. The corrosion products incorporated into the passive film changed the local structure and component of the passive film, lowering its stability

  16. Review and evaluation of metallic TRU nuclear waste consolidation methods

    International Nuclear Information System (INIS)

    Montgomery, D.R.; Nesbitt, J.F.

    1983-08-01

    The US Department of Energy established the Commercial Waste Treatment Program to develop, demonstrate, and deploy waste treatment technology. In this report, viable methods are identified that could consolidate the volume of metallic wastes generated in a fuel reprocessing facility. The purpose of this study is to identify, evaluate, and rate processes that have been or could be used to reduce the volume of contaminated/irradiated metallic waste streams and to produce an acceptable waste form in a safe and cost-effective process. A technical comparative evaluation of various consolidation processes was conducted, and these processes were rated as to the feasibility and cost of producing a viable product from a remotely operated radioactive process facility. Out of the wide variety of melting concepts and consolidation systems that might be applicable for consolidating metallic nuclear wastes, the following processes were selected for evaluation: inductoslay melting, rotating nonconsumable electrode melting, plasma arc melting, electroslag melting with two nonconsumable electrodes, vacuum coreless induction melting, and cold compaction. Each process was evaluated and rated on the criteria of complexity of process, state and type of development required, safety, process requirements, and facility requirements. It was concluded that the vacuum coreless induction melting process is the most viable process to consolidate nuclear metallic wastes. 11 references

  17. Impacts of swine manure pits on groundwater quality

    International Nuclear Information System (INIS)

    Krapac, I.G.; Dey, W.S.; Roy, W.R.; Smyth, C.A.; Storment, E.; Sargent, S.L.; Steele, J.D.

    2002-01-01

    New information is presented on impacts on groundwater by manure storage in deep ground pits. - Manure deep-pits are commonly used to store manure at confined animal feeding operations. However, previous to this study little information had been collected on the impacts of deep-pits on groundwater quality to provide science-based guidance in formulating regulations and waste management strategies that address risks to human health and the environment. Groundwater quality has been monitored since January 1999 at two hog finishing facilities in Illinois that use deep-pit systems for manure storage. Groundwater samples were collected on a monthly basis and analyzed for inorganic and bacteriological constituent concentrations. The two sites are located in areas with geologic environments representing different vulnerabilities for local groundwater contamination. One site is underlain by more than 6 m of clayey silt, and 7-36 m of shale. Concentrations of chloride, ammonium, phosphate, and potassium indicated that local groundwater quality had not been significantly impacted by pit leakage from this facility. Nitrate concentrations were elevated near the pit, often exceeding the 10 mg N/l drinking water standard. Isotopic nitrate signatures suggested that the nitrate was likely derived from soil organic matter and fertilizer applied to adjacent crop fields. At the other site, sandstone is located 4.6-6.1 m below land surface. Chloride concentrations and δ 15 N and δ 18 O values of dissolved nitrate indicated that this facility may have limited and localized impacts on groundwater. Other constituents, including ammonia, potassium, phosphate, and sodium were generally at or less than background concentrations. Trace- and heavy-metal concentrations in groundwater samples collected from both facilities were at concentrations less than drinking water standards. The concentration of inorganic constituents in the groundwater would not likely impact human health. Fecal

  18. Impacts of swine manure pits on groundwater quality

    Energy Technology Data Exchange (ETDEWEB)

    Krapac, I.G.; Dey, W.S.; Roy, W.R.; Smyth, C.A.; Storment, E.; Sargent, S.L.; Steele, J.D

    2002-12-01

    New information is presented on impacts on groundwater by manure storage in deep ground pits. - Manure deep-pits are commonly used to store manure at confined animal feeding operations. However, previous to this study little information had been collected on the impacts of deep-pits on groundwater quality to provide science-based guidance in formulating regulations and waste management strategies that address risks to human health and the environment. Groundwater quality has been monitored since January 1999 at two hog finishing facilities in Illinois that use deep-pit systems for manure storage. Groundwater samples were collected on a monthly basis and analyzed for inorganic and bacteriological constituent concentrations. The two sites are located in areas with geologic environments representing different vulnerabilities for local groundwater contamination. One site is underlain by more than 6 m of clayey silt, and 7-36 m of shale. Concentrations of chloride, ammonium, phosphate, and potassium indicated that local groundwater quality had not been significantly impacted by pit leakage from this facility. Nitrate concentrations were elevated near the pit, often exceeding the 10 mg N/l drinking water standard. Isotopic nitrate signatures suggested that the nitrate was likely derived from soil organic matter and fertilizer applied to adjacent crop fields. At the other site, sandstone is located 4.6-6.1 m below land surface. Chloride concentrations and {delta}{sup 15}N and {delta}{sup 18}O values of dissolved nitrate indicated that this facility may have limited and localized impacts on groundwater. Other constituents, including ammonia, potassium, phosphate, and sodium were generally at or less than background concentrations. Trace- and heavy-metal concentrations in groundwater samples collected from both facilities were at concentrations less than drinking water standards. The concentration of inorganic constituents in the groundwater would not likely impact human

  19. Method of processing radioactive metal wastes

    International Nuclear Information System (INIS)

    Inoue, Yoichi; Kitagawa, Kazuo; Tsuzura, Katsuhiko.

    1980-01-01

    Purpose: To enable long and safety storage for radioactive metal wastes such as used fuel cans after the procession or used pipe, instruments and the likes polluted with various radioactive substances, by compacting them to solidify. Method: Metal wastes such as used fuel cans, which have been cut shorter and reprocessed, are pressed into generally hexagonal blocks. The block is charged in a capsule of a hexagonal cross section made of non-gas permeable materials such as soft steels, stainless steels and the likes. Then, the capsule is subjected to static hydraulic hot pressing as it is or after deaeration and sealing. While various combinations are possible for temperature, pressure and time as the conditions for the static hydraulic hot pressing, dense block with no residual gas pores can be obtained, for example, under the conditions of 900 0 C, 1000 Kg/cm 2 and one hour where the wastes are composed of zircaloy. (Kawakami, Y.)

  20. Option managing for radioactive metallic waste from the decommissioning of Kori Unit 1

    Energy Technology Data Exchange (ETDEWEB)

    Kessel, David S.; Kim, Chagn Lak [KEPCO International Nuclear Graduate School (KINGS), Ulsan (Korea, Republic of)

    2017-06-15

    The purpose of this paper is to evaluate several leading options for the management of radioactive metallic waste against a set of general criteria including safety, cost effectiveness, radiological dose to workers and volume reduction. Several options for managing metallic waste generated from decommissioning are evaluated in this paper. These options include free release, controlled reuse, and direct disposal of radioactive metallic waste. Each of these options may involve treatment of the metal waste for volume reduction by physical cutting or melting. A multi-criteria decision analysis was performed using the Analytic Hierarchy Process (AHP) to rank the options. Melting radioactive metallic waste to produce metal ingots with controlled reuse or free release is found to be the most effective option.

  1. The kinetics of pitting corrosion of carbon steel

    International Nuclear Information System (INIS)

    Marsh, G.P.; Taylor, K.J.; Sooi, Z.

    1988-02-01

    The development of an improved statistical method for analysing pit growth data to take account of the difference in area of laboratory specimens and full sized high level nuclear waste containers is described. Statistical analysis of data from pit growth experiments with large area (460 cm 2 ) plates of BS 4360 steel have indicated that the depth distributions correlate most closely with a limited distribution function. This correlation implies that previous statistical analyses to estimate the maximum pit depths in full size containers, which were made using unlimited distribution functions, will be pessimistic. An evaluation of the maximum feasible pitting period based on estimating the period during which the oxygen diffusion flux is sufficient to stabilise a passive film on carbon steel containers has indicated that this is of the order of 125 years rather than the full 1000 year container life. The estimate is sensitive to the value of the leakage current assumed to flow through the passive film, and therefore work is planned to measure this accurately in relevant granitic environments. (author)

  2. Cleanup Verification Package for the 126-F-1, 184-F Powerhouse Ash Pit

    International Nuclear Information System (INIS)

    Clark, S.W.; Sulloway, H.M.

    2007-01-01

    This cleanup verification package documents completion of remedial action for the 126-F-1, 184-F Powerhouse Ash Pit. This waste site received coal ash from the 100-F Area coal-fired steam plant. Leakage of process effluent from the 116-F-14 , 107-F Retention Basins flowed south into the ash pit, contaminating the northern portion

  3. COGEMA experience on retrieving and conditioning solid radwaste previously stored in pits. The La Hague North-West pit case

    International Nuclear Information System (INIS)

    Bodin, F.; Alexandre, D.; Fournier, P.

    1999-01-01

    Short lived, low and medium level waste called 'technological waste' produced by the La Hague Reprocessing Plant have been stored in the La Hague North-West concrete-lined pits until implementation at ANDRA's Centre de Stockage de la Manche (CSM). COGEMA decided to retrieve and condition 11,000 m 3 of humid solid radwaste, stored in bulk in pits. On account of the variety of radwaste kinds, retrieving and conditioning operations represented real challenge. One goal of these operations was to ensure that the work was performed in complete safety towards environment with optimum containment and with the best radiation protection for the personnel involved. COGEMA decided to split the work into two phases. The feedback from the first phase was very helpful to the second phase. This report describes the experience gained from February 1990 to December 1998, taking into account radwaste and integrated dose rate results conditioning such waste. The procedures and means used and improved by COGEMA to comply with ANDRA's storage standards and the ever-decreasing financial costs generated by the workers, allowed to retrieve and condition 11,000 m 3 of old solid radwaste with competitive costs and in complete safety and protection of the environment. (author)

  4. Decontamination of alpha contaminated metallic waste by cerium IV redox process

    International Nuclear Information System (INIS)

    Shah, J.G.; Dhami, P.S.; Gandhi, P.M.; Wattal, P.K.

    2012-01-01

    Decontamination of alpha contaminated metallic waste is an important aspect in the management of waste generated during dismantling and decommissioning of nuclear facilities. Present work on cerium redox process targets decontamination of alpha contaminated metallic waste till it qualifies for the non alpha waste category for disposal in near surface disposal facility. Recovery of the alpha radio nuclides and cerium from aqueous secondary waste streams was also studied deploying solvent extraction process and established. The alpha-lean secondary waste stream has been immobilised in cement based matrix for final disposal. (author)

  5. Abstraction of Models for Pitting and Crevice Corrosion of Drip Shield and Waste Package Outer Barrier

    Energy Technology Data Exchange (ETDEWEB)

    K. Mon

    2001-08-29

    This analyses and models report (AMR) was conducted in response to written work direction (CRWMS M and O 1999a). ICN 01 of this AMR was developed following guidelines provided in TWP-MGR-MD-000004 REV 01, ''Technical Work Plan for: Integrated Management of Technical Product Input Department'' (BSC 2001, Addendum B). The purpose and scope of this AMR is to review and analyze upstream process-level models (CRWMS M and O 2000a and CRWMS M and O 2000b) and information relevant to pitting and crevice corrosion degradation of waste package outer barrier (Alloy 22) and drip shield (Titanium Grade 7) materials, and to develop abstractions of the important processes in a form that is suitable for input to the WAPDEG analysis for long-term degradation of waste package outer barrier and drip shield in the repository. The abstraction is developed in a manner that ensures consistency with the process-level models and information and captures the essential behavior of the processes represented. Also considered in the model abstraction are the probably range of exposure conditions in emplacement drifts and local exposure conditions on drip shield and waste package surfaces. The approach, method, and assumptions that are employed in the model abstraction are documented and justified.

  6. Abstraction of Models for Pitting and Crevice Corrosion of Drip Shield and Waste Package Outer Barrier

    International Nuclear Information System (INIS)

    Mon, K.

    2001-01-01

    This analyses and models report (AMR) was conducted in response to written work direction (CRWMS M and O 1999a). ICN 01 of this AMR was developed following guidelines provided in TWP-MGR-MD-000004 REV 01, ''Technical Work Plan for: Integrated Management of Technical Product Input Department'' (BSC 2001, Addendum B). The purpose and scope of this AMR is to review and analyze upstream process-level models (CRWMS M and O 2000a and CRWMS M and O 2000b) and information relevant to pitting and crevice corrosion degradation of waste package outer barrier (Alloy 22) and drip shield (Titanium Grade 7) materials, and to develop abstractions of the important processes in a form that is suitable for input to the WAPDEG analysis for long-term degradation of waste package outer barrier and drip shield in the repository. The abstraction is developed in a manner that ensures consistency with the process-level models and information and captures the essential behavior of the processes represented. Also considered in the model abstraction are the probably range of exposure conditions in emplacement drifts and local exposure conditions on drip shield and waste package surfaces. The approach, method, and assumptions that are employed in the model abstraction are documented and justified

  7. Geochemical speciation and dynamic of copper in tropical semi-arid soils exposed to metal-bearing mine wastes

    Energy Technology Data Exchange (ETDEWEB)

    Perlatti, Fabio [Department of Environmental Technology, National Department of Mineral Production – DNPM, Rua Dr. José Lourenço, 90560115-280 Fortaleza, CE (Brazil); Graduate Course of Ecology and Natural Resources, Department of Biology, Federal University of Ceará – UFC, Building 906, 60455-760, Fortaleza, CE (Brazil); Otero, Xosé Luis; Macias, Felipe [Department of Edaphology and Agricultural Chemistry, Faculty of Biology, University of Santiago de Compostela – USC, Rúa Lope Gómez de Marzoa, s/n. Campus sur, 15782 Santiago de Compostela (Spain); Ferreira, Tiago Osório, E-mail: toferreira@usp.br [Department of Soil Science, University of São Paulo (ESALQ/USP), Av. Pádua Dias, 11, 13418-900, Piracicaba, SP (Brazil); Graduate Course of Ecology and Natural Resources, Department of Biology, Federal University of Ceará – UFC, Building 906, 60455-760, Fortaleza, CE (Brazil)

    2014-12-01

    The potentially hazardous effects of rock wastes disposed at open pit in three different areas (Pr: Ore processing; Wr: Waste rock and Bd: Border) of an abandoned copper mine were evaluated in this study, with emphasis on acid drainage generation, metal contamination and copper geochemical dynamics in soils. Samples of waste rock were analyzed by Energy dispersive X-ray fluorescence (XRF), scanning electron microscopy with microanalysis (SEM-EDS) and X-ray diffraction (XRD). Soil samples were analyzed to determine the total metal contents (XRF), mineralogy (XRD), pH (H2O and H2O2), organic and inorganic carbon, % of total N, S and P, particle size, and a sequential extraction procedure was used to identify the different copper fractions. As a result of the prevalence of carbonates over sulphides in the wastes, the soil pH remained close to neutral, with absence of acid mine drainage. The geochemical interaction between these mineral phases seems to be the main mechanism to release Cu{sup 2+} ions. Total Cu in soils from the Pr area reached 11,180 mg.kg{sup −1}, while in Wr and Bd areas the values reached, on average, 4683 and 1086 mg.kg{sup −1}, respectively, indicating a very high level of soil contamination. In the Pr and Wr, the Cu was mainly associated with carbonates and amorphous iron oxides. In the Bd areas, the presence of vegetation has influenced the geochemical behavior of copper by increasing the dissolution of carbonates, affecting the buffer capacity of soils against sulphide oxidation, reducing the pH levels and enhancing the proportion of exchangeable and organic bound Cu. The present findings show that the use of plants or organic amendments in mine sites with high concentration of Cu carbonate-containing wastes should be viewed with caution, as the practice may enhance the mobilization of copper to the environment due to an increase in the rate of carbonates dissolution. - Highlights: • The hazardous effects of mine waste rocks at

  8. Stochastic production phase design for an open pit mining complex with multiple processing streams

    Science.gov (United States)

    Asad, Mohammad Waqar Ali; Dimitrakopoulos, Roussos; van Eldert, Jeroen

    2014-08-01

    In a mining complex, the mine is a source of supply of valuable material (ore) to a number of processes that convert the raw ore to a saleable product or a metal concentrate for production of the refined metal. In this context, expected variation in metal content throughout the extent of the orebody defines the inherent uncertainty in the supply of ore, which impacts the subsequent ore and metal production targets. Traditional optimization methods for designing production phases and ultimate pit limit of an open pit mine not only ignore the uncertainty in metal content, but, in addition, commonly assume that the mine delivers ore to a single processing facility. A stochastic network flow approach is proposed that jointly integrates uncertainty in supply of ore and multiple ore destinations into the development of production phase design and ultimate pit limit. An application at a copper mine demonstrates the intricacies of the new approach. The case study shows a 14% higher discounted cash flow when compared to the traditional approach.

  9. Pitting corrosion of copper. An equilibrium - mass transport study

    International Nuclear Information System (INIS)

    Taxen, C.

    2002-08-01

    A mathematical model for the propagation of corrosion pits is described and used to calculate the potentials below which copper is immune to pitting. The model uses equilibrium data and diffusion coefficients and calculates the stationary concentration profiles of 26 aqueous species from the bulk water outside a corrosion pit to the site of the metal dissolution. Precipitation of oxides and salts of copper is considered. Studied conditions include water compositions from tap waters to seawater at the temperatures 25 deg C and 75 deg C. Carbonate and sulphate are aggressive towards copper because of complex formation with divalent copper. Carbonate is less aggressive in a corrosion pit than outside at the pH of the bulk. Carbonate carries acidity out from the pit, favours oxide formation and may prevent the initiation of acidic corrosion pits. The concentration profiles are used to estimate the maximum propagation rates for a corrosion pit. A high potential is found to be the most important factor for the rate of propagation. The levels of potential copper can sustain, as corrosion potentials are discussed in terms of the stability of cuprous oxide as a cathode material for oxygen reduction relative to non-conducting cupric phases

  10. Pitting corrosion of copper. An equilibrium - mass transport study

    Energy Technology Data Exchange (ETDEWEB)

    Taxen, C. [Swedish Corrosion Inst., Stockholm (Sweden)

    2002-08-01

    A mathematical model for the propagation of corrosion pits is described and used to calculate the potentials below which copper is immune to pitting. The model uses equilibrium data and diffusion coefficients and calculates the stationary concentration profiles of 26 aqueous species from the bulk water outside a corrosion pit to the site of the metal dissolution. Precipitation of oxides and salts of copper is considered. Studied conditions include water compositions from tap waters to seawater at the temperatures 25 deg C and 75 deg C. Carbonate and sulphate are aggressive towards copper because of complex formation with divalent copper. Carbonate is less aggressive in a corrosion pit than outside at the pH of the bulk. Carbonate carries acidity out from the pit, favours oxide formation and may prevent the initiation of acidic corrosion pits. The concentration profiles are used to estimate the maximum propagation rates for a corrosion pit. A high potential is found to be the most important factor for the rate of propagation. The levels of potential copper can sustain, as corrosion potentials are discussed in terms of the stability of cuprous oxide as a cathode material for oxygen reduction relative to non-conducting cupric phases.

  11. Cost estimate of grouting the proposed test pits at Idaho National Engineering Laboratory using the ORNL-recommended grouts

    International Nuclear Information System (INIS)

    Spence, R.D.

    1987-08-01

    EG and G Idaho will construct three experimental pits to simulate the TRU waste trenches at Idaho National Engineering Laboratory (INEL). Two of these pits will be grouted and then one will be destructively examined as soon as the grout cures and the other will be monitored for 10 years. Oak Ridge National Laboratory (ORNL) is evaluating grouts and will recommend a grout to EG and G Idaho to reduce the permeability of the pit, fill the large voids, and encapsulate the waste. A previous ORNL report (ORNL/TM-9881) discusses the grouts evaluated and the grout recommended based on those evaluations. This report evaluates the economics of grouting the experimental pits. The cost of double grouting two of the EG and G Idaho design pits at the Idaho National Engineering Laboratory using lance injection was estimated to be $100,000. Jet grouting the same two pits was estimated to cost $85,000. Both should be tried as part of the test EG and G Idaho is conducting

  12. Anaerobic bioleaching of metals from waste activated sludge

    KAUST Repository

    Meulepas, Roel J W; Gonzalez-Gil, Graciela; Teshager, Fitfety Melese; Witharana, Ayoma; Saikaly, Pascal; Lens, Piet Nl L

    2015-01-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether

  13. Why do Pit-Hours outlive the Pit?

    NARCIS (Netherlands)

    S.R. Ozturk (Sait); M. van der Wel (Michel); D.J.C. van Dijk (Dick)

    2015-01-01

    markdownabstract__Abstract__ We study why a majority of trades still happen during the pit hours, i.e. when the trading pit is open, even after the pit ceased to be a liquid and informative venue. We investigate the case of 30-year U.S. Treasury futures using a ten-years-long intraday data set

  14. Anaerobic bioleaching of metals from waste activated sludge

    KAUST Repository

    Meulepas, Roel J W

    2015-05-01

    Heavy metal contamination of anaerobically digested waste activated sludge hampers its reuse as fertilizer or soil conditioner. Conventional methods to leach metals require aeration or the addition of leaching agents. This paper investigates whether metals can be leached from waste activated sludge during the first, acidifying stage of two-stage anaerobic digestion without the supply of leaching agents. These leaching experiments were done with waste activated sludge from the Hoek van Holland municipal wastewater treatment plant (The Netherlands), which contained 342μgg-1 of copper, 487μgg-1 of lead, 793μgg-1 of zinc, 27μgg-1 of nickel and 2.3μgg-1 of cadmium. During the anaerobic acidification of 3gdry weightL-1 waste activated sludge, 80-85% of the copper, 66-69% of the lead, 87% of the zinc, 94-99% of the nickel and 73-83% of the cadmium were leached. The first stage of two-stage anaerobic digestion can thus be optimized as an anaerobic bioleaching process and produce a treated sludge (i.e., digestate) that meets the land-use standards in The Netherlands for copper, zinc, nickel and cadmium, but not for lead.

  15. Metallic elements occurrences within metallic fragments in the municipal waste incineration bottom ash

    Science.gov (United States)

    Kowalski, Piotr; Kasina, Monika; Michalik, Marek

    2017-04-01

    Bottom ash (BA) from municipal solid waste incineration (MSWI) is composed of grainy ash material, residual components and metallic fragments (from few µm up to 3-5 cm). Its mineral and chemical composition is related to the composition of the waste stream in the incinerator operational area. Wide use of thermal techniques in management of solid waste makes important the studies on valuable components and their distribution within the material in terms of their further processing. By using various valorization or extraction techniques it is possible to extend the range of its possible further application. To investigate metallic elements distribution within metallic fragments of the MSWI BA material produced in municipal waste incineration plant in Poland were collected in 2015 and 2016. BA and its components were investigated using spectroscopic methods of chemical analysis: ICP-OES, ICP-MS, LECO and EDS (used for microanalysis during SEM observations). BA is a material rich in Si (22.5 wt%), Ca (13.4 wt%), Fe (4 wt%), Al (5.2 wt%) and Na (3.5 wt%), composed of equal part of amorphous (silicate glass dominated) and crystalline phase (rich in silicates, aluminosilicates, oxides of non- and metallic elements and sulphates). The content of metallic elements (Al, Fe, Mg, Ti, Mn, Cr, Ni, Sc, Mo, Cu, Pb, Zn, Sn) is 11.5 wt% with domination of Al (5.2 wt%) and Fe (4 wt%) and elevated values of Mg (1 wt%), Ti (0.54 wt%), Cu (0.26 wt%) and Zn (0.27 wt%) (Kowalski et al., 2016). They were mostly concentrated in the form of metallic fragments, mainly as metallic inclusions in the size of 1-20 µm and separated metallic grains in the size of 50-300 µm. Metallic fragments present in the BA are characterized by their composition heterogeneity and various oxygen content. Fragments are rarely composed of single metallic element and usually in their composition up to few main elements dominated over others. The most common were Fe-, Al- and Zn-rich fragments forming respectively

  16. Extent of chromium contamination beneath the 60s pits in the Chemical Waste Landfill at Sandia National Laboratories, Albuquerque, New Mexico

    International Nuclear Information System (INIS)

    Johnson, R.

    1994-09-01

    Plume trademark and SitePlanner trademark were used to analyze the extent of chromium contamination beneath the 60s pits in the Chemical Waste Landfill at Sandia National Laboratories. On the basis of Plume trademark's analysis with currently available sampling and the proper locations for that sampling. Finally, a retrospective study was conducted for the site that evaluated the potential for cost savings if the characterization effort had followed an adaptive sampling program approach. Included in this retrospective study was an analysis of the impacts that spatial autocorrelation, soft information, and alternative sampling program goals have on sampling program progress. The conclusion is that by relying on an adaptive sampling program approach at the 60s pits, and leveraging the little soft information that is available for this location, a significant gain in information could have been realized for the same number of bores

  17. Optic Nerve Pit

    Science.gov (United States)

    ... Conditions Frequently Asked Questions Español Condiciones Chinese Conditions Optic Nerve Pit What is optic nerve pit? An optic nerve pit is a ... may be seen in both eyes. How is optic pit diagnosed? If the pit is not affecting ...

  18. A numerical study of under-deposit pitting corrosion in sour petroleum pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Z.; Sand, K.W.; Teevens, P.J. [Broadsword Corrosion Engineering Ltd., Calgary, AB (Canada)

    2010-07-01

    Insufficient fluid velocity in petroleum pipelines can lead to the deposit of sand, corrosion products, and non-corrosion products on the pipe's metal surface, which in turn can lead to pitting corrosion. There is currently no reliable means of detecting and preventing the pitting process. This paper presented a computerized simulation tool that used the finite element method to model mass transfer-governed internal pitting corrosion under solids deposition in sour petroleum pipelines. The computational domain consisted of a hemispherical pit and a thin stagnant solution film under a surface deposit. The moving mesh method was used to track pitting growth. A Poisson equation was used to determine aqueous path migration of ions. Pitting corrosion rates were estimated using the Nernst-Planck equation. The model was used to predict the effects of different operating parameters on pitting corrosion rates. The model can be used to develop pigging and in-line-inspection (ILI) procedures. 35 refs., 2 tabs., 16 figs.

  19. Assessment of Concrete Repair Techniques for Radiologically-Contaminated Tank Farm Pump and Valve Pits

    International Nuclear Information System (INIS)

    MINTEER, D.J.

    2000-01-01

    As part of the scope of Project W-314, ''Tank Farm Restoration and Safe Operations,'' the condition of pump and valve pit walls and floors is being assessed, and repairs made as needed, to support upgrading the infrastructure necessary to safely transfer tank waste for treatment. Flaws in the surfaces of the pits (e.g., concrete crack/faults, protective coating deterioration) must be repaired to ensure containment integrity and to facilitate future decontamination of the pits. This engineering study presents a cost/risk/benefit evaluation of concrete and protective coating repair methods in pump and valve pits using various manual and remote tool systems

  20. Metals partitioning resulting from rotary kiln incineration of hazardous waste

    International Nuclear Information System (INIS)

    Richards, M.K.; Fournier, D.J. Jr.

    1992-01-01

    In response to the need for date on the partitioning of trace metals from hazardous waste incinerators, an extensive series of test was conducted in the summer of 1991 at the USEPA Incineration Research Facility (IRF) in Jefferson, Arkansas. These tests were conducted in the IRF's rotary kiln incinerator system (RKS) equipped with a pilot-scale Calvert Flux-Force/Condensation scrubber as the primary air pollution control system (APCS). The purpose of this test series was to extend the data base on trace metal partitioning and to investigate the effects of variations in incinerator operation on metal partitioning. Another objective was to evaluate the effectiveness of the scrubber for collecting flue gas metals. This series is a continuation of an ongoing IRF research program investigating trace metal partitioning and APCS collection efficiencies. Two previous test series were conducted using the RKS equipped with a venturi/packed-column scrubber and a single-state ionizing wet scrubber. The primary objective of this test series was to determine the fate of six hazardous and four nonhazardous trace metals fed to the RKS in a synthetic, organic-contaminated solid waste matrix. The six hazardous trace metals used were arsenic, barium, cadmium, chromium, mercury, and lead. The four nonhazardous trace metals--bismuth, copper, magnesium, and strontium--were included primarily to supply data to evaluate their potential for use as surrogates. The temperature, waste feed chlorine content, and scrubber pressure drop. The test program objectives were to identify. The partitioning of metals among kiln ash, scrubber liquor, and flue gas. Changes in metal partitioning related to variations in kiln exit gas temperature and waste feed chlorine content. The efficiency of the Calvert scrubber for collecting flue gas metals. The effects of scrubber pressure drop on metal collection efficiencies. 2 figs., 2 tabs

  1. Fire testing of 55 gallon metal waste drums for dry waste storage

    International Nuclear Information System (INIS)

    Hasegawa, H.K.; Staggs, K.J.; Doughty, S.M.

    1993-07-01

    The primary goal of this test program was to conduct a series of fire test to provide information on the fire performance of 55 gallon metal waste drums used for solid waste disposal at Department Of Energy (DOE) facilities. This program was limited in focus to three different types of 55 gallon drums, one radiant heat source, and one specific fire size. The initial test was a single empty 55 gallon drum exposed to a standard ASTME-119 time temperature curve for over 10 minutes. The full scale tests involved metal drums exposed to a 6' diameter flammable liquid fire for a prescribed period of time. The drums contained simulated dry waste materials of primarily class A combustibles. The test results showed that a conventional 55 gallon drum with a 1in. bung would blow its lid consistently

  2. Heavy metal content of combustible municipal solid waste in Denmark.

    Science.gov (United States)

    Riber, Christian; Fredriksen, Gry S; Christensen, Thomas H

    2005-04-01

    Data on the heavy metal composition of outlets from Danish incinerators was used to estimate the concentration of Zn, Cu, Pb, Cr, Ni, Cd, As and Hg in combustible waste (wet as received) at 14 Danish incinerators, representing about 80% of the waste incinerated in Denmark. Zn (1020 mg kg(-1)), Cu (620 mg kg(-1)) and Pb (370 mg kg(-1)) showed the highest concentration, whereas Hg (0.6 mg kg(-1)) showed the lowest concentration. The variation among the incinerators was in most cases within a factor of two to three, except for Cr that in two cases showed unexplained high concentrations. The fact that the data represent many incinerators and, in several cases, observations from a period of 4 to 5 years provides a good statistical basis for evaluating the content of heavy metals in combustible Danish waste. Such data may be used for identifying incinerators receiving waste with high concentrations of heavy metals suggesting the introduction of source control, or, if repeated in time, the data must also be used for monitoring the impacts of national regulation controlling heavy metals. It is recommended that future investigations consider the use of sample digestion methods that ensure complete digestion in order to use the data for determining the total heavy metal content of waste.

  3. Central Shops Burning/Rubble Pit 631-6G Additional Sampling and Monitor Well Installation Report

    International Nuclear Information System (INIS)

    Palmer, E.

    1995-02-01

    The Central Shops Burning/Rubble Pit 631-6G was constructed in 1951 as an unlined earthen pit in surficial sediments for disposal and incineration of potentially hazardous substances, such as metals and organic solvents

  4. Norm Levels in Mine Pit Lakes in South-Western Spain

    International Nuclear Information System (INIS)

    Manjón, G.; Galván, J.; Mantero, J.; Díaz, I.; García-Tenorio, R.

    2015-01-01

    Former mining activities in a pyritic area in south-western Spain have generated mine pits in which underground water and rainwater has accumulated. The accumulated waters have produced oxidation of the pyrite and, consequently, the pit water has become acidic, causing the dissolution of metals and radionuclides of natural origin. The paper discusses the activity concentration levels of uranium isotopes and other radionuclides in water samples and sediments collected from these mine pit lakes. Tributaries of the nearby Odiel River, when crossing the mining area, show low pH values and high concentrations of uranium isotopes due to acid mine drainage. Through the analysis of several isotope activity ratios, the presence of radionuclides in the pit lakes and the influence of these radionuclides on the surrounding area and the Odiel River are evaluated. (author)

  5. Isolation of Metals from Liquid Wastes: Reactive in Turbulent Thermal Reactors

    International Nuclear Information System (INIS)

    Wendt, Jost O.L.

    2001-01-01

    A Generic Technology for treatment of DOE Metal-Bearing Liquid Waste The DOE metal-bearing liquid waste inventory is large and diverse, both with respect to the metals (heavy metals, transuranics, radionuclides) themselves, and the nature of the other species (annions, organics, etc.) present. Separation and concentration of metals is of interest from the standpoint of reducing the volume of waste that will require special treatment or isolation, as well as, potentially, from the standpoint of returning some materials to commerce by recycling. The variety of metal-bearing liquid waste in the DOE complex is so great that it is unlikely that any one process (or class of processes) will be suitable for all material. However, processes capable of dealing with a wide variety of wastes will have major advantages in terms of process development, capital, and operating costs, as well as in environmental and safety permitting. Moreover, to the extent that a process operates well with a variety of metal-bearing liquid feedwastes, its performance is likely to be relatively robust with respect to the inevitable composition variations in each waste feed. One such class of processes involves high-temperature treatment of atomized liquid waste to promote reactive capture of volatile metallic species on collectible particulate substrates injected downstream of a flame zone. Compared to low-temperature processes that remove metals from the original liquid phase by extraction, precipitation, ion exchange, etc., some of the attractive features of high-temperature reactive scavenging are: The organic constituents of some metal-bearing liquid wastes (in particular, some low-level mixed wastes) must be treated thermally in order to meet the requirements of the Resource Conservation and Recovery Act (RCRA) and Toxic Substances Control Act (TSCA), and the laws of various states. No species need be added to an already complex liquid system. This is especially important in light of the fact

  6. Pit morphology studies of iron and steel in alkaline chloride environment using EMPA technique

    International Nuclear Information System (INIS)

    Benjamin, S.E.; Sykes, J.M.

    1993-01-01

    A comparative study of iron and steel in stimulated alkaline chloride solutions showed that Swedish iron has better reproducibility in terms of pitting potentials as compared to ordinary hot rolled mild steel. This study was undertaken to reason this pitting behavior on the basis of number and the nature of inclusions present in both the metals. Electron probe microanalysis technique (EPMA) was utilised to contemplate the origin of pits, the solution chemistry of the pits and finally the nature of the rust product. (author)

  7. Treatment and minimization of heavy metal-containing wastes 1995

    International Nuclear Information System (INIS)

    Hager, J.P.; Mishra, B.; Litz, J.L.

    1995-01-01

    This symposium was held in conjunction with the 1995 Annual Meeting of the Minerals, Metals and Materials Society in Las Vegas, Nevada, February 12--16, 1995. The purpose of this meeting was to provide a forum for exchange of state-of-the-art information on treating and minimizing heavy metal-containing wastes. Papers were categorized under the following broad headings: aqueous processing; waste water treatment; thermal processing and stabilization; processing of fly ash, flue dusts, and slags; and processing of lead, mercury, and battery wastes. Individual papers have been processed separately for inclusion in the appropriate data bases

  8. Induction melting for volume reduction of metallic TRU wastes

    International Nuclear Information System (INIS)

    Westsik, J.H. Jr.; Montgomery, D.R.; Katayama, Y.B.; Ross, W.A.

    1986-01-01

    Volume reduction of metallic transuranic wastes offers economic and safety incentives for treatment of wastes generated at a hypothetical commercial fuel reprocessing facility. Induction melting has been identified as the preferred process for volume reduction of spent fuel hulls, fuel assembly hardware, and failed equipment from a reprocessing plant. Bench-scale melting of Zircaloy and stainless steel mixtures has been successfully conducted in a graphite crucible inside a large vacuum chamber. A low-melting-temperature alloy forms that has demonstrated excellent leach resistance. The alloy can be used to encapsulate other metallic wastes that cannot be melted using the existing equipment design

  9. Cleanup Verification Package for the 100-F-20, Pacific Northwest Laboratory Parallel Pits

    International Nuclear Information System (INIS)

    Appel, M.J.

    2007-01-01

    This cleanup verification package documents completion of remedial action for the 100-F-20, Pacific Northwest Laboratory Parallel Pits waste site. This waste site consisted of two earthen trenches thought to have received both radioactive and nonradioactive material related to the 100-F Experimental Animal Farm

  10. Electrochemical Corrosion Studies for Modeling Metallic Waste Form Release Rates

    International Nuclear Information System (INIS)

    Poineau, Frederic; Tamalis, Dimitri

    2016-01-01

    The isotope 99 Tc is an important fission product generated from nuclear power production. Because of its long half-life (t 1/2 = 2.13 ∙ 105 years) and beta-radiotoxicity (β - = 292 keV), it is a major concern in the long-term management of spent nuclear fuel. In the spent nuclear fuel, Tc is present as an alloy with Mo, Ru, Rh, and Pd called the epsilon-phase, the relative amount of which increases with fuel burn-up. In some separation schemes for spent nuclear fuel, Tc would be separated from the spent fuel and disposed of in a durable waste form. Technetium waste forms under consideration include metallic alloys, oxide ceramics and borosilicate glass. In the development of a metallic waste form, after separation from the spent fuel, Tc would be converted to the metal, incorporated into an alloy and the resulting waste form stored in a repository. Metallic alloys under consideration include Tc–Zr alloys, Tc–stainless steel alloys and Tc–Inconel alloys (Inconel is an alloy of Ni, Cr and iron which is resistant to corrosion). To predict the long-term behavior of the metallic Tc waste form, understanding the corrosion properties of Tc metal and Tc alloys in various chemical environments is needed, but efforts to model the behavior of Tc metallic alloys are limited. One parameter that should also be considered in predicting the long-term behavior of the Tc waste form is the ingrowth of stable Ru that occurs from the radioactive decay of 99 Tc ( 99 Tc → 99 Ru + β - ). After a geological period of time, significant amounts of Ru will be present in the Tc and may affect its corrosion properties. Studying the effect of Ru on the corrosion behavior of Tc is also of importance. In this context, we studied the electrochemical behavior of Tc metal, Tc-Ni alloys (to model Tc-Inconel alloy) and Tc-Ru alloys in acidic media. The study of Tc-U alloys has also been performed in order to better understand the nature of Tc in metallic spent fuel. Computational modeling

  11. Pitting morphologies of zirconium base alloys in aqueous and non aqueous chloride media

    International Nuclear Information System (INIS)

    Palit, G.C.; Gadiyar, H.S.

    1988-01-01

    Pitting morphology of zirconium and Zr-Cr alloys in aqueous chloride and nonaqueous methanol + 0.4 per cent HCl solution was investigated and observed to follow different modes in these two environments. While in aqueous chloride solution pitting was transgranular and randomly oriented, in methanol-chloride solution pits were observed to initiate and propagate along the grain boundaries. In aqueous chloride solution very irregular and sponge like zirconium metal was formed inside the pit while in methanol-chloride solution the pits were crystallographic in nature. Optical microscopy has revealed that pits preferentially initiate and propagate along scratch line in aqueous chloride solution, but such was not the case in nonaqueous methanol-chloride solution. The nature and the mechanism operating in the catastropic failure of these materials are investigated. (author). 10 refs., 11 figs

  12. Process for treating waste water having low concentrations of metallic contaminants

    Science.gov (United States)

    Looney, Brian B; Millings, Margaret R; Nichols, Ralph L; Payne, William L

    2014-12-16

    A process for treating waste water having a low level of metallic contaminants by reducing the toxicity level of metallic contaminants to an acceptable level and subsequently discharging the treated waste water into the environment without removing the treated contaminants.

  13. Remote Sensing Combined with Field Spectroscopy for the Detection and Monitoring of Heavy Metal Contamination from Informal E-waste Recycling

    Science.gov (United States)

    Friedlander, L. R.; Garb, Y.

    2017-12-01

    Electronic waste (e-waste) is one of today's fastest growing waste streams. Made up of discarded electronics, e-waste disposal is complex. However, e-waste also provides economic opportunity through the processing and extraction of precious metals. Sometimes referred to as "urban mining," this recycling operates informally or illegally and is characterized by dangerous practices such as, open-pit burning, acid leaching, and burning of low value wastes. Poorly controlled e-waste recycling releases dangerous contaminants, especially heavy metals, directly to the surface environment where they can infiltrate water resources and spread through precipitation events. Despite growing recognition of the prevalence of unregulated e-waste processing, systematic data on the extent and persistence of the released contamination is still limited. In general, contamination is established through techniques that provide only a snapshot in time and in a limited geographic area. Here we present preliminary results from attempts to combine field, laboratory, and remote sensing studies toward a systematic remote sensing methodology for e-waste contamination detection and monitoring. The ongoing work utilizes a tragic "natural experiment," in which over 500 e-waste burn sites were active over more than a decade in a variety of agricultural, residential, and natural contexts. We have collected over 100 soil samples for which we have both XRF and ICP-AES measurements showing soil Pb concentrations as high as 14000 ppm. We have also collected 480 in-situ reflectance spectra with corresponding soil samples over 4 field transects of areas with long-term burn activity. The most heavily contaminated samples come from within the burn sites and are made up of ash. Field spectra of these samples reflect their dark color with low overall reflectance and shallow spectral features. These spectra are challenging to use for image classification due to their similarity with other low-reflectance parts

  14. Metal Recovery from Industrial Solid Waste — Contribution to Resource Sustainability

    Science.gov (United States)

    Yang, Yongxiang

    Increased demand of metals has driven the accelerated mining and metallurgical production in recent years, causing fast depletion of primary metals resources. On the contrary, the mining and metallurgical industry generates large amount of solid residues and waste such as tailings, slags, flue dust and leach residues, with relative low valuable metal contents. On the other hand, end-of-life (EoL) consumer products form another significant resources. The current technology and processes for primary metals production are not readily applicable for direct metals extraction from these waste materials, and special adaptation and tailor-made processes are required. In the present paper, various solid waste resources are reviewed, and current technologies and R&D trends are discussed. The recent research at author's group is illustrated for providing potential solutions to future resource problems, including metal recovery from MSW incinerator bottom ashes, zinc recovery from industrial ashes and residues, and rare earth metals recovery from EoL permanent magnets.

  15. Competitive metal sorption and desorption onto Kappaphycus alvarezii, seaweed waste biomass

    International Nuclear Information System (INIS)

    Lee, K.O.; Nazaruddin Ramli; Mamot Said; Musa Ahmad; Suhaimi Mohd Yasir; Arbakariya Ariff

    2011-01-01

    Competitive metal sorption and desorption onto Kappaphycus alvarezii waste biomass were investigated. Metal sorption capacities were 0.82 mg Cr (III)/ g, 0.73 mg Ni (II)/ g, 0.67 mg Cd (II)/ g, 0.65 mg Cu( II)/ g and 0.64 mg Zn (II)/ g in multi metal system. Whereas, desorption efficiencies were 66.08 %, 71.50 % and 80.44 % using 0.1 M HNO 3 , 0.1 M HCl and 0.1 M H 2 SO 4 , respectively. The metal sorption sequence were Cr(III) > Ni(II) > Cd(II) > Cu(II) > Zn(II), while metal desorption sequence were Cd(II) > Zn(II) > Cu(II) > Ni(II) > Cr(III). Fourier transformed infrared spectroscopy (FTIR) technique was used to characterize the seaweed waste biomass. FTIR analysis shown that carbonyl (-C-O) and nitrile (-C≡N) groups interact with the metal ions. The experiments result revealed that Kappaphycus alvarezii waste biomass represent an attractive candidate to remove multi metal ions. (author)

  16. Competitive metal sorption and desorption onto Kappaphycus alvarezii, seaweed waste biomass

    Energy Technology Data Exchange (ETDEWEB)

    Lee, K O; Ramli, Nazaruddin; Said, Mamot; Ahmad, Musa [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), Bangi, selangor (Malaysia); Yasir, Suhaimi Mohd [School of Sciences and Technology, Universiti Malaysia Sabah (UMS), Sabah (Malaysia); Arbakariya Ariff, E-mail: naza@ukm.my [Faculty of Biotechnology and Biomolecular science, Universiti Putra Malaysia (UPM), Serdang, Selangor (Malaysia)

    2011-07-15

    Competitive metal sorption and desorption onto Kappaphycus alvarezii waste biomass were investigated. Metal sorption capacities were 0.82 mg Cr (III)/ g, 0.73 mg Ni (II)/ g, 0.67 mg Cd (II)/ g, 0.65 mg Cu( II)/ g and 0.64 mg Zn (II)/ g in multi metal system. Whereas, desorption efficiencies were 66.08 %, 71.50 % and 80.44 % using 0.1 M HNO{sub 3}, 0.1 M HCl and 0.1 M H{sub 2}SO{sub 4}, respectively. The metal sorption sequence were Cr(III) > Ni(II) > Cd(II) > Cu(II) > Zn(II), while metal desorption sequence were Cd(II) > Zn(II) > Cu(II) > Ni(II) > Cr(III). Fourier transformed infrared spectroscopy (FTIR) technique was used to characterize the seaweed waste biomass. FTIR analysis shown that carbonyl (-C-O) and nitrile (-C{identical_to}N) groups interact with the metal ions. The experiments result revealed that Kappaphycus alvarezii waste biomass represent an attractive candidate to remove multi metal ions. (author)

  17. INEL cold test pit demonstration of improvements in information derived from non-intrusive geophysical methods over buried waste sites

    International Nuclear Information System (INIS)

    1993-01-01

    The objectives of this research project were to lay the foundation for further improvement in the use of geophysical methods for detection of buried wastes, and to increase the information content derived from surveys. Also, an important goal was to move from mere detection to characterization of buried wastes. The technical approach to achieve these objectives consisted of: (1) Collect a data set of high spatial density; (2) Acquire data with multiple sensors and integrate the interpretations inferred from the various sensors; (3) Test a simplified time domain electromagnetic system; and (4) Develop imaging and display formats of geophysical data readily understood by environmental scientists and engineers. The breadth of application of this work is far reaching. Not only are uncontrolled waste pits and trenches, abandoned underground storage tanks, and pipelines found throughout most US DOE facilities, but also at military installations and industrial facilities. Moreover, controlled land disposal sites may contain ''hot spots'' where drums and hazardous material may have been buried. The technologies addressed by the R ampersand D will benefit all of these activities

  18. Bio-processing of solid wastes and secondary resources for metal extraction - A review.

    Science.gov (United States)

    Lee, Jae-Chun; Pandey, Banshi Dhar

    2012-01-01

    Metal containing wastes/byproducts of various industries, used consumer goods, and municipal waste are potential pollutants, if not treated properly. They may also be important secondary resources if processed in eco-friendly manner for secured supply of contained metals/materials. Bio-extraction of metals from such resources with microbes such as bacteria, fungi and archaea is being increasingly explored to meet the twin objectives of resource recycling and pollution mitigation. This review focuses on the bio-processing of solid wastes/byproducts of metallurgical and manufacturing industries, chemical/petrochemical plants, electroplating and tanning units, besides sewage sludge and fly ash of municipal incinerators, electronic wastes (e-wastes/PCBs), used batteries, etc. An assessment has been made to quantify the wastes generated and its compositions, microbes used, metal leaching efficiency etc. Processing of certain effluents and wastewaters comprising of metals is also included in brief. Future directions of research are highlighted. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Shallow land burial of low-level radioactive waste

    International Nuclear Information System (INIS)

    Daniel, D.E.

    1983-01-01

    Low-level radioactive waste has been produced since the early 1940's. Most of it has been buried in shallow pits at 11 existing sites. Several of the existing sites have performed poorly. Inability to control flow of surface and ground water into and out of disposal pits has been the most important problem. Lack of attention to design of earthen covers over the waste and improper emplacement of the waste in the pits have also contributed to poor performance. Several steps are recommended for improving disposal practices: (1) Waste settlement can be minimized by stacking wastes neatly into pits rather than dumping them randomly; (2) the earthen cover can be made to perform better by making it thicker and by maintaining it properly; and (3) groundwater contamination can be minimized by siting disposal facilities at locations with favorable geohydrologic characteristics. In addition, improved designs are needed for earthen covers, and technology for predicting ground water contamination in the saturated/unsaturated soils that underlie the waste also needs improvement

  20. Characterization of a Fe-based alloy system for an AFCI metallic waste form - 16134

    International Nuclear Information System (INIS)

    Williamson, Mark J.; Sindelar, Robert L.

    2009-01-01

    The AFCI waste management program aims to provide a minimum volume stable waste form for high level radioactive waste from the various process streams. The AFCI Integrated Waste Management Strategy document has identified a Fe-Zr metallic waste form (MWF) as the baseline alloy for disposal of Tc metal, undissolved solids, and TRUEX fission product wastes. Several candidate alloys have been fabricated using vacuum induction melting to investigate the limits of waste loading as a function of Fe and Zr content. Additional melts have been produced to investigate source material composition. These alloys have been characterized using SEM/EDS and XRD. Phase assemblage and specie partitioning of Re metal (surrogate for Tc) and noble metal FP elements into the phases is reported. (authors)

  1. The state of the art on the radioactive metal waste recycling technologies

    International Nuclear Information System (INIS)

    Oh, Won Jin; Moon, Jei Kwon; Jung, Chong Hun; Park, Sang Yoon

    1997-09-01

    As the best strategy to manage the radioactive metal wastes which are generated during operation and decommissioning of nuclear facilities, the following recycling technologies are investigated. 1. decontamination technologies for radioactive metal waste recycling 2. decontamination waste treatment technologies. 3. residual radioactivity evaluation technologies. (author). 260 refs., 26 tabs., 31 figs

  2. Volume Reduction of Decommissioning Radioactive Burnable and Metal Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Min, B. Y.; Lee, Y. J.; Yun, G. S.; Lee, K. W.; Moon, J. K. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Choi, Y. K.; Cho, J. H. [SunKwang Atomic Energy Safety Co., Seoul (Korea, Republic of)

    2014-10-15

    A large quantity of radioactive waste was generated during the decommissioning projects. For the purpose of the volume reduction and clearance for decommissioning wastes from decommissioning projects, the incineration and high melting technology has been selected for the decommissioning wastes treatment. The volume reduction of the combustible wastes through the incineration technologies has merits from the view point of a decrease in the amount of waste to be disposed of resulting in a reduction of the disposal cost. Incineration is generally accepted as a method of reducing the volume of radioactive waste. The incineration technology is an effective treatment method that contains hazardous chemicals as well as radioactive contamination. Incinerator burns waste at high temperature. Incineration of a mixture of chemically hazardous and radioactive materials, known as 'mixed waste,' has two principal goals: to reduce the volume and total chemical toxicity of the waste. Incineration itself does not destroy the metals or reduce the radioactivity of the waste. A proven melting technology is currently used for low-level waste (LLW) at several facilities worldwide. These facilities use melting as a means of processing LLW for unrestricted release of the metal or for recycling within the nuclear sector. About 16.4 tons of decommissioning combustible waste has been treated using Oxygen Enriched incineration. The incineration facility operated quite smoothly through the analysis major critical parameters of off-gas.

  3. Volume Reduction of Decommissioning Radioactive Burnable and Metal Wastes

    International Nuclear Information System (INIS)

    Min, B. Y.; Lee, Y. J.; Yun, G. S.; Lee, K. W.; Moon, J. K.; Choi, Y. K.; Cho, J. H.

    2014-01-01

    A large quantity of radioactive waste was generated during the decommissioning projects. For the purpose of the volume reduction and clearance for decommissioning wastes from decommissioning projects, the incineration and high melting technology has been selected for the decommissioning wastes treatment. The volume reduction of the combustible wastes through the incineration technologies has merits from the view point of a decrease in the amount of waste to be disposed of resulting in a reduction of the disposal cost. Incineration is generally accepted as a method of reducing the volume of radioactive waste. The incineration technology is an effective treatment method that contains hazardous chemicals as well as radioactive contamination. Incinerator burns waste at high temperature. Incineration of a mixture of chemically hazardous and radioactive materials, known as 'mixed waste,' has two principal goals: to reduce the volume and total chemical toxicity of the waste. Incineration itself does not destroy the metals or reduce the radioactivity of the waste. A proven melting technology is currently used for low-level waste (LLW) at several facilities worldwide. These facilities use melting as a means of processing LLW for unrestricted release of the metal or for recycling within the nuclear sector. About 16.4 tons of decommissioning combustible waste has been treated using Oxygen Enriched incineration. The incineration facility operated quite smoothly through the analysis major critical parameters of off-gas

  4. Comparative assessment of metallurgical recovery of metals from electronic waste with special emphasis on bioleaching.

    Science.gov (United States)

    Priya, Anshu; Hait, Subrata

    2017-03-01

    Waste electrical and electronic equipment (WEEE) or electronic waste (e-waste) is one of the fastest growing waste streams in the urban environment worldwide. The core component of printed circuit board (PCB) in e-waste contains a complex array of metals in rich quantity, some of which are toxic to the environment and all of which are valuable resources. Therefore, the recycling of e-waste is an important aspect not only from the point of waste treatment but also from the recovery of metals for economic growth. Conventional approaches for recovery of metals from e-waste, viz. pyrometallurgical and hydrometallurgical techniques, are rapid and efficient, but cause secondary pollution and economically unviable. Limitations of the conventional techniques have led to a shift towards biometallurgical technique involving microbiological leaching of metals from e-waste in eco-friendly manner. However, optimization of certain biotic and abiotic factors such as microbial species, pH, temperature, nutrients, and aeration rate affect the bioleaching process and can lead to profitable recovery of metals from e-waste. The present review provides a comprehensive assessment on the metallurgical techniques for recovery of metals from e-waste with special emphasis on bioleaching process and the associated factors.

  5. Design review report: AN valve pit upgrades for Project W-314, tank farm restoration and safe operations

    International Nuclear Information System (INIS)

    Boes, K.A.

    1998-01-01

    This Design Review Report (DRR) documents the contractor design verification methodology and records associated with project W-314's AN Valve Pit Upgrades design package. The DRR includes the documented comments and their respective dispositions for this design. Acceptance of the comment dispositions and closure of the review comments is indicated by the signatures of the participating reviewers. Project W-314, Tank Farm Restoration and Safe Operations, is a project within the Tank Waste Remediation System (TWRS) Tank Waste Retrieval Program. This project provides capital upgrades for the existing Hanford tank farms' waste transfer, instrumentation, ventilation, and electrical infrastructure systems. To support established TWRS programmatic objectives, the project is organized into two distinct phases. The initial focus of the project (i.e., Phase 1) is on waste transfer system upgrades needed to support the TWRS Privatization waste feed delivery system. Phase 2 of the project will provide upgrades to support resolution of regulatory compliance issues, improve tank infrastructure reliability, and reduce overall plant operating/maintenance costs. Within Phase 1 of the W-314 project, the waste transfer system upgrades are further broken down into six major packages which align with the project's work breakdown structure. Each of these six sub-elements includes the design, procurement, and construction activities necessary to accomplish the specific tank farm upgrades contained within the package. The first package to be performed is the AN Valve Pit Upgrades package. The scope of the modifications includes new pit cover blocks, valve manifolds, leak detectors, transfer line connections (for future planned transfer lines), and special protective coating for the 241-AN-A and 241-AN-B valve pits

  6. Chemical Decontamination of Metallic Waste from Uranium Conversion Plant Dismantling

    International Nuclear Information System (INIS)

    Hwang, D. S.; Choi, Y. D.; Hwang, S. T.; Park, J. H.; Byun, J. I.; Jang, N. S.

    2005-01-01

    Korea Atomic Energy Research Institute (KAERI) started a decommissioning program of the uranium conversion plant. Pre-work was carried as follows; installation of the access control facility, installation of a changing room and shower room, designation of an emergency exit way and indicating signs, installation of a radiation management facility, preparation of a storage area for tools and equipments, inspection and load test of crane, distribution and packaging of existing waste, and pre-decontamination of the equipment surface and the interior. First, decommissioning work was performed in kiln room, which will be used for temporary radioactive waste storage room. Kiln room housed hydro fluorination rotary kiln for production of uranium tetra-fluoride. The kiln is about 0.8 m in diameter and 5.5 m long. The total dismantled waste was 6,690 kg, 73 % of which was metallic waste and 27 % the others such as cable, asbestos, concrete, secondary waste, etc. And effluent treatment room and filtration room were dismantled for installation of decontamination equipment and lagoon sludge treatment equipment. There were tanks and square mixer in these rooms. The total dismantled waste was 17,250 kg, 67% of which was metallic waste and 33% the others. These dismantled metallic wastes consist of stainless and carbon steel. In this paper, the stainless steel plate and pipe were decontaminated by the chemical decontamination with ultrasonic

  7. Feed Materials Production Center waste management plan (Revision to NLCO-1100, R.6)

    International Nuclear Information System (INIS)

    Watts, R.E.; Allen, T.; Castle, S.A.; Hopper, J.P.; Oelrich, R.L.

    1986-01-01

    In the process of producing uranium metal products used in Department of Energy (DOE) defense programs at other DOE facilities, various types of wastes are generated at the Feed Materials Production Center (FMPC). Process wastes, both generated and stored, are discussed in the Waste Management Plan and include low-level radioactive waste (LLW), mixed hazardous/radioactive waste, and sanitary/industrial waste. Scrap metal waste and wastes requiring special remediation are also addressed in the Plan. The Waste Management Plan identifies the comprehensive programs developed to address safe storage and disposition of all wastes from past, present, and future operations at the FMPC. Waste streams discussed in this Plan are representative of the wastes generated and waste types that concern worker and public health and safety. Budgets and schedules for implementation of waste disposition are also addressed. The waste streams receiving the largest amount of funding include LLW approved for shipment by DOE/ORO to the Nevada Test Site (NTS) (MgF 2 , slag leach filter cake, and neutralized raffinate); remedial action wastes (waste pits, K-65 silo waste); thorium; scrap metal (contaminated and noncontaminated ferrous and copper scrap); construction rubble and soil generated from decontamination and decommissioning of outdated facilities; and low-level wastes that will be handled through the Low-Level Waste Processing and Shipping System (LLWPSS). Waste Management milestones are also provided. The Waste Management Plan is divided into eight major sections: Introduction; Site Waste and Waste Generating Process; Strategy; Projects and Operations; Waste Stream Budgets; Milestones; Quality Assurance for Waste Management; and Environmental Monitoring Program

  8. In situ vitrification application to buried waste: Final report of intermediate field tests at Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Callow, R.A.; Weidner, J.R.; Loehr, C.A.; Bates, S.O.; Thompson, L.E.; McGrail, B.P.

    1991-08-01

    This report describes two in situ vitrification field tests conducted on simulated buried waste pits during June and July 1990 at the Idaho National Engineering Laboratory. In situ vitrification, an emerging technology for in place conversion of contaminated soils into a durable glass and crystalline waste form, is being investigated as a potential remediation technology for buried waste. The overall objective of the two tests was to access the general suitability of the process to remediate waste structures representative of buried waste found at Idaho National Engineering Laboratory. In particular, these tests, as part of a treatability study, were designed to provide essential information on the field performance of the process under conditions of significant combustible and metal wastes and to test a newly developed electrode feed technology. The tests were successfully completed, and the electrode feed technology successfully processed the high metal content waste. Test results indicate the process is a feasible technology for application to buried waste. 33 refs., 109 figs., 39 tabs

  9. Metallography of pitted aluminum-clad, depleted uranium fuel

    International Nuclear Information System (INIS)

    Nelson, D.Z.; Howell, J.P.

    1994-01-01

    The storage of aluminum-clad fuel and target materials in the L-Disassembly Basin at the Savannah River Site for more than 5 years has resulted in extensive pitting corrosion of these materials. In many cases the pitting corrosion of the aluminum clad has penetrated in the uranium metal core, resulting in the release of plutonium, uranium, cesium-137, and other fission product activity to the basin water. In an effort to characterize the extent of corrosion of the Mark 31A target slugs, two unirradiated slug assemblies were removed from basin storage and sent to the Savannah River Technology Center for evaluation. This paper presents the results of the metallography and photographic documentation of this evaluation. The metallography confirmed that pitting depths varied, with the deepest pit found to be about 0.12 inches (3.05 nun). Less than 2% of the aluminum cladding was found to be breached resulting in less than 5% of the uranium surface area being affected by corrosion. The overall integrity of the target slug remained intact

  10. Induction melting for volume reduction of metallic TRU wastes

    International Nuclear Information System (INIS)

    Westsik, J.H. Jr.; Montgomery, D.R.; Katayama, Y.B.; Ross, W.A.

    1986-02-01

    Volume reduction of metallic transuranic wastes offers economic and safety incentives for treatment of wastes generated at a hypothetical commercial fuel reprocessing facility. Induction melting has been identified as the preferred process for volume reduction of spent fuel hulls, fuel assembly hardware, and failed equipment from a reprocessing plant. Bench-scale melting of Zircaloy and stainless steel mixtures has been successfully conducted in a graphite crucible inside a large vacuum chamber. A low-melting-temperature alloy forms that has demonstrated excellent leach resistance. The alloy can be used to encapsulate other metallic wastes that cannot be melted using the existing equipment design. 18 refs., 4 figs., 3 tabs

  11. MINE WASTE TECHNOLOGY PROGRAM; PHOSPHATE STABILIZATION OF HEAVY METALS CONTAMINATED MINE WASTE YARD SOILS, JOPLIN, MISSOURI NPL SITE

    Science.gov (United States)

    This document summarizes the results of Mine Waste Technology Project 22-Phosphate Stabilization of Heavy Metals-Contaminated Mine Waste Yard Soils. Mining, milling, and smelting of ores near Joplin, Missouri, have resulted in heavy metal contamination of the area. The Joplin s...

  12. Some thermal analysis aspects of metal encapsulated waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-01-01

    This paper is to summarize two waste management schemes: (1) packaging for extended storage of LWR spent fuel assemblies, with the capability for simple conversion either to terminal storage if a ''throwaway'' fuel cycle is ultimately adopted or to a form that can be reprocessed and (2) packaging for the terminal storage of solidified high-level wastes when the reprocessing of spent fuel is initiated. Only concepts utilizing metals or metal alloys to encapsulate either spent fuel or solidified high-level waste forms have been considered. Conceptual process flow sheets have been constructed to allow potential advantages and disadvantages of encapsulation alternatives to be identified in comparison with more conventional reference processes. Identification is also made of uncertainties of the analysis due to a lack of fundamental data required to perform evaluations. 3 tables

  13. Thermal treatment of toxic metals of industrial hazardous wastes with fly ash and clay

    Energy Technology Data Exchange (ETDEWEB)

    Singh, I.B. [Regional Research Laboratory, Council of Scientific and Industrial Research, Hoshangabad Road, Bhopal 462026 (India)]. E-mail: ibsingh58@yahoo.com; Chaturvedi, K. [Regional Research Laboratory, Council of Scientific and Industrial Research, Hoshangabad Road, Bhopal 462026 (India); Morchhale, R.K. [Regional Research Laboratory, Council of Scientific and Industrial Research, Hoshangabad Road, Bhopal 462026 (India); Yegneswaran, A.H. [Regional Research Laboratory, Council of Scientific and Industrial Research, Hoshangabad Road, Bhopal 462026 (India)

    2007-03-06

    Waste generated from galvanizing and metal finishing processes is considered to be a hazardous due to the presence of toxic metals like Pb, Cu, Cr, Zn, etc. Thermal treatment of such types of wastes in the presence of clay and fly ash can immobilizes their toxic metals to a maximum level. After treatment solidified mass can be utilized in construction or disposed off through land fillings without susceptibility of re-mobilization of toxic metals. In the present investigation locally available clay and fly ash of particular thermal power plant were used as additives for thermal treatment of both of the wastes in their different proportions at 850, 900 and 950 deg. C. Observed results indicated that heating temperature to be a key factor in the immobilization of toxic metals of the waste. It was noticed that the leachability of metals of the waste reduces to a negligible level after heating at 950 deg. C. Thermally treated solidified specimen of 10% waste and remaining clay have shown comparatively a higher compressive strength than clay fired bricks used in building construction. Though, thermally heated specimens made of galvanizing waste have shown much better strength than specimen made of metal finishing waste. The lechability of toxic metals like Cr, Cu, Pb and Zn became far below from their regulatory threshold after heating at 950 deg. C. Addition of fly ash did not show any improvement either in engineering property or in leachability of metals from the solidified mass. X-ray diffraction (XRD) analysis of the solidified product confirmed the presence of mixed phases of oxides of metals.

  14. Bio-processing of solid wastes and secondary resources for metal extraction – A review

    International Nuclear Information System (INIS)

    Lee, Jae-chun; Pandey, Banshi Dhar

    2012-01-01

    Highlights: ► Review focuses on bio-extraction of metals from solid wastes of industries and consumer goods. ► Bio-processing of certain effluents/wastewaters with metals is also included in brief. ► Quantity/composition of wastes are assessed, and microbes used and leaching conditions included. ► Bio-recovery using bacteria, fungi and archaea is highlighted for resource recycling. ► Process methodology/mechanism, R and D direction and scope of large scale use are briefly included. - Abstract: Metal containing wastes/byproducts of various industries, used consumer goods, and municipal waste are potential pollutants, if not treated properly. They may also be important secondary resources if processed in eco-friendly manner for secured supply of contained metals/materials. Bio-extraction of metals from such resources with microbes such as bacteria, fungi and archaea is being increasingly explored to meet the twin objectives of resource recycling and pollution mitigation. This review focuses on the bio-processing of solid wastes/byproducts of metallurgical and manufacturing industries, chemical/petrochemical plants, electroplating and tanning units, besides sewage sludge and fly ash of municipal incinerators, electronic wastes (e-wastes/PCBs), used batteries, etc. An assessment has been made to quantify the wastes generated and its compositions, microbes used, metal leaching efficiency etc. Processing of certain effluents and wastewaters comprising of metals is also included in brief. Future directions of research are highlighted.

  15. Treatment of radioactive metallic waste by the electro-slag melting method

    International Nuclear Information System (INIS)

    Ochiai, Atsuhiro; Nagura, Kanetake; Noura, Tsuyoshi

    1983-01-01

    The applicability of the electro-slag melting method for treating plutonuim contaminated metallic waste was studied. A 100kg test furnace was built and simulated metallic waste was melted and solidified in this furnace. Waste volume was reduced to 1/25 with a decontamination factor of 25 and the slag and the copper mold are repeatedly usable. The process is expected to be employed in the project of PWTF (Plutonium contaminated Wate Treatment Facilities). (author)

  16. Metal waste forms from treatment of EBR-II spent fuel

    International Nuclear Information System (INIS)

    Abraham, D. P.

    1998-01-01

    Demonstration of Argonne National Laboratory's electrometallurgical treatment of spent nuclear fuel is currently being conducted on irradiated, metallic driver fuel and blanket fuel elements from the Experimental Breeder Reactor-II (EBR-II) in Idaho. The residual metallic material from the electrometallurgical treatment process is consolidated into an ingot, the metal waste form (MWF), by employing an induction furnace in a hot cell. Scanning electron microscopy (SEM) and chemical analyses have been performed on irradiated cladding hulls from the driver fuel, and on samples from the alloy ingots. This paper presents the microstructures of the radioactive ingots and compares them with observations on simulated waste forms prepared using non-irradiated material. These simulated waste forms have the baseline composition of stainless steel - 15 wt % zirconium (SS-15Zr). Additions of noble metal elements, which serve as surrogates for fission products, and actinides are made to that baseline composition. The partitioning of noble metal and actinide elements into alloy phases and the role of zirconium for incorporating these elements is discussed in this paper

  17. Decontamination method for radiation-contaminated metal waste

    International Nuclear Information System (INIS)

    Suwa, Takeshi; Kuribayashi, Nobuhide; Yasumune, Taketoshi.

    1991-01-01

    In immersing radiation-contaminated metal wastes into a sulfuric acid solution thereby peeling and removing radioactive deposition cruds and dissolving the surface of the matrix metals to eliminate radioactive contaminants, when the potential of the sulfuric acid solution is shifted to a higher direction by more than a certain level due to the increase of the amount of metal ions leached from the cruds and the matrix material, the leached metal ions are electrolytically reduced to control the potential of the sulfuric acid solution to less than a predetermined potential level. Although the dissolving rate is increased as the concentration of the sulfuric acid solution is higher, it is preferably from 0.5 to 2 mol/l, since higher concentration increases the load on the waste liquid processing. Further, the temperature for solution is set to higher than a room temperature and, preferably from 50 to 90degC. Further, the potential level of the solution, although varies somewhat depending on the concentration of the leached metal ions and the temperature, is preferably controlled to less than 0.1 to 0.2 V. This can attain high decontaminating effect in a short period of time by using a sulfuric acid solution alone. (T.M.)

  18. Electrochemical Corrosion Studies for Modeling Metallic Waste Form Release Rates

    Energy Technology Data Exchange (ETDEWEB)

    Poineau, Frederic [Univ. of Nevada, Las Vegas, NV (United States); Tamalis, Dimitri [Florida Memorial Univ., Miami Gardens, FL (United States)

    2016-08-01

    The isotope 99Tc is an important fission product generated from nuclear power production. Because of its long half-life (t1/2 = 2.13 ∙ 105 years) and beta-radiotoxicity (β⁻ = 292 keV), it is a major concern in the long-term management of spent nuclear fuel. In the spent nuclear fuel, Tc is present as an alloy with Mo, Ru, Rh, and Pd called the epsilon-phase, the relative amount of which increases with fuel burn-up. In some separation schemes for spent nuclear fuel, Tc would be separated from the spent fuel and disposed of in a durable waste form. Technetium waste forms under consideration include metallic alloys, oxide ceramics and borosilicate glass. In the development of a metallic waste form, after separation from the spent fuel, Tc would be converted to the metal, incorporated into an alloy and the resulting waste form stored in a repository. Metallic alloys under consideration include Tc–Zr alloys, Tc–stainless steel alloys and Tc–Inconel alloys (Inconel is an alloy of Ni, Cr and iron which is resistant to corrosion). To predict the long-term behavior of the metallic Tc waste form, understanding the corrosion properties of Tc metal and Tc alloys in various chemical environments is needed, but efforts to model the behavior of Tc metallic alloys are limited. One parameter that should also be considered in predicting the long-term behavior of the Tc waste form is the ingrowth of stable Ru that occurs from the radioactive decay of 99Tc (99Tc → 99Ru + β⁻). After a geological period of time, significant amounts of Ru will be present in the Tc and may affect its corrosion properties. Studying the effect of Ru on the corrosion behavior of Tc is also of importance. In this context, we studied the electrochemical behavior of Tc metal, Tc-Ni alloys (to model Tc-Inconel alloy) and Tc-Ru alloys in acidic media. The study of Tc-U alloys has also been performed in order to better understand the

  19. Geochemistry, water balance, and stable isotopes of a “clean” pit lake at an abandoned tungsten mine, Montana, USA

    International Nuclear Information System (INIS)

    Gammons, Christopher H.; Pape, Barbara L.; Parker, Stephen R.; Poulson, Simon R.; Blank, Carrine E.

    2013-01-01

    Highlights: • An abandoned open pit mine is now a 30 m deep lake with excellent water quality. • Concentrations of sulfate, nutrients, and most trace metals are extremely low. • Based on water isotopes, the lake is 30% evaporated with a 2.5 yr residence time. • Stable isotopes of DIC and DO track in-lake bio-geochemical processes. • Phytoplankton are active at depths as great as 20 m. - Abstract: The Calvert Mine is a small tungsten-rich (scheelite) skarn deposit in a remote, mountainous region of southwest Montana, USA. The open-pit mine closed in the 1970s and subsequently flooded to form a pit lake that is roughly conical in shape, 30 m deep and 120 m in diameter, with no surface inlet or outlet. The lake is holomictic with a groundwater flow-through hydrology and an estimated residence time of 2.5–5 y. Water isotopes show that the lake is at an approximate steady state with respect to water balance and has experienced 30% evaporation. The lake has a near-neutral pH, exceptional clarity, and extremely low concentrations of nutrients, sulfate, and most metals, including tungsten. Manganese concentrations are slightly elevated and increase with depth towards the sediment–water interface. Despite seasonally anoxic conditions in the deep water, dissolved Fe concentrations are orders of magnitude lower than Mn, suggesting that insufficient organic carbon is present in the sediment of this oligotrophic lake to drive bacterial Fe reduction. Based on stable isotope fingerprinting, diffuse seepage that enters a nearby headwater stream at the base of a large waste-rock pile can be directly linked to the partially evaporated pit lake. However, this seepage has neutral pH and low metal concentrations, and poses no threats to the environment. Stable isotopes of dissolved inorganic carbon (DIC) and dissolved oxygen (DO) are used to track the relative importance of photosynthesis and respiration with depth. In summer, a zone of high productivity exists near the

  20. The pitting resistance of AISI 316 stainless steel passivated in diluted nitric acid

    International Nuclear Information System (INIS)

    Barbosa, M.A.

    1983-01-01

    The pitting resistance of AISI 316 stainless steel after passivation in diluted nitric acid was studied in comparison with that of non-passivated specimens. The passivation treatment increased the pitting potential but decreased the resistance to crevice corrosion under open circuit conditions in aerated sea water. Immersion in the nitric acid solution was found to remove the sulphide inclusions from the metal surface, thus eliminating the most susceptible sites for attack. In the absence of sulphide particles pitting nucleated at aluminium-rich oxides. (author)

  1. Sol-Gel Stabilization of Heavy Metal Waste

    National Research Council Canada - National Science Library

    Cropek, Donald

    2000-01-01

    .... The types of media are varied and include soils, ashes, and sludges. Waste having a leachable metal concentration above the Toxicity Characteristic Leaching Procedure limit established by the U.S...

  2. Development on inspection and recognition procedure of clearance level of radioactivity in metal wastes, to secure social safety for reused metals

    International Nuclear Information System (INIS)

    Hattori, Takatoshi

    2002-01-01

    The Central Research Institute of Electric Power Industry developed a new procedure automatically measurable on radioactivity level in metal wastes in high precision by using the newest three-dimensional (3D) shape measuring technology and 3D Monte-Carlo computing technology (a code to probabilistically compute formation and movement of gamma-ray from metal wastes to detectors) to contribute to inspection and recognition of clearance level of radioactivity. This procedure can prove no super micro amount of radioactivity of 250 Bq in metal wastes of testing objects. As this proof is an evaluation of conservative safety side showing no pollution at any 100 sq cm of surface of the metal wastes on considering for taking-out reference on matters, for its price, the procedure cancelled all of labors to test all of metal wastes surfaces by survey meter, and so on, and feasibility of overlook of pollution at places difficult to measure by using survey meters can perfectly excluded. Its practical tester is planned to produce at 2002 fiscal year, and testing performance against actual metal wastes is planned to confirm by its proof-test on 2003 to 2004 fiscal years. (G.K.)

  3. Application of a modified electrochemical system for surface decontamination of radioactive metal waste

    International Nuclear Information System (INIS)

    Lee, J.H.; Lim, Y.K.; Yang, H.Y.; Shin, S.W.; Song, M.J.

    2003-01-01

    Conventional and modified electrolytic decontamination experiments were performed in a solution of sodium sulfate for the decontamination of carbon steel as the simulated metal wastes which are generated in large amounts from nuclear power plants. The effect of reaction time, current density and concentration of electrolytes in the modified electrolytic decontamination system were examined to remove the surface contamination of the simulated radioactive metal wastes. As for the results of this research, the modified electrochemical decontamination process can decontaminate more effectively than the conventional decontamination process by applying different anode material which causes higher induced electro-motive forces. When 0.5 M sodium sulfate, 0.4 A/cm 2 current density and 30 minutes reaction time were applied in the modified process, a 16 μm thickness change that is expected to remove most surface contamination in radioactive metal wastes was achieved on carbon steel which is the main material of radioactive metal waste in nuclear power plants. The decontamination efficiency of metal waste showed similar results with the small and large lab-scale modified electrochemical system. The application of this modified electrolytic decontamination system is expected to play a considerable role for decontamination of radioactive metal waste in nuclear power plants in the near future. (author)

  4. ON THE PROPAGATION OF OPEN AND COVERED PIT IN 316L STAINLESS STEEL

    International Nuclear Information System (INIS)

    Heurtault, Stéphane; Robin, Raphaël; Rouillard, Fabien; Vivier, Vincent

    2016-01-01

    Highlights: • The propagation of a single pit was investigated with a flow micro-device. • Both in depth and radial pit propagation were characterized. • The formation of a salt film in the pit was discussed. - Abstract: Pitting corrosion on stainless steel has been widely studied during the last decades, but since it is a stochastic process, it remains difficult to analyze experimentally such a phenomenon. In this work, reproducible single pits were performed on 316L steel by using an experimental setup based on the use of a glass microcapillary to locally supply chloride ions on the steel surface in order to characterize the pit propagation. This original approach allowed obtaining new results about pit propagation. Indeed, it was possible to control the presence of a metallic cap covering the pit by adjusting the experimental parameters (potential – chloride to sulfate ratio – temperature). The presence of this cover was shown to be an important issue concerning the propagation mechanism. It was also possible to study the evolution of both the pit depth and the pit diameter as a function of various parameters. Then, based on the simulation of the current densities at the pit bottom and at the pit aperture, a special attention has been paid for the investigation of the local propagation mechanism.

  5. Perchlorate reduction during electrochemically induced pitting corrosion of zero-valent titanium (ZVT)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chunwoo, E-mail: clee@doosanhydro.com [Department of Research and Development, Doosan Hydro Technology, Inc, Tampa, FL 33619 (United States); Batchelor, Bill [Zachry Department of Civil Engineering, Texas A and M University, College Station, TX 77840 (United States); Park, Sung Hyuk [Environmental and Engineering Research Team, GS Engineering and Construction Research Institute, Youngin, Kyunggi-do 449-831 (Korea, Republic of); Han, Dong Suk; Abdel-Wahab, Ahmed [Chemical Engineering Program, Texas A and M University at Qatar, Education City, Doha, PO Box 23874 (Qatar); Kramer, Timothy A.

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer ZVT is oxidized during electrochemically induced pitting corrosion to produce reactive soluble species. Black-Right-Pointing-Pointer Perchlorate is effectively reduced to chloride by soluble titanium species. Black-Right-Pointing-Pointer Solution pH and surface area of ZVT showed negligible effects on rates of perchlorate reduction. - Abstract: Zero-valent metals and ionic metal species are a popular reagent for the abatement of contaminants in drinking water and groundwater and perchlorate is a contaminant of increasing concern. However, perchlorate degradation using commonly used reductants such as zero-valent metals and soluble reduced metal species is kinetically limited. Titanium in the zero-valent and soluble states has a high thermodynamic potential to reduce perchlorate. Here we show that perchlorate is effectively reduced to chloride by soluble titanium species in a system where the surface oxide film is removed from ZVT and ZVT is oxidized during electrochemically induced pitting corrosion to produce reactive soluble species. The pitting potential of ZVT was measured as 12.77 {+-} 0.04 V (SHE) for a 100 mM solution of perchlorate. The rate of perchlorate reduction was independent of the imposed potential as long as the potential was maintained above the pitting potential, but it was proportional to the applied current. Solution pH and surface area of ZVT electrodes showed negligible effects on rates of perchlorate reduction. Although perchlorate is effectively reduced during electrochemically induced corrosion of ZVT, this process may not be immediately applicable to perchlorate treatment due to the high potentials needed to produce active reductants, the amount of titanium consumed, the inhibition of perchlorate removal by chloride, and oxidation of chloride to chlorine.

  6. Perchlorate reduction during electrochemically induced pitting corrosion of zero-valent titanium (ZVT)

    International Nuclear Information System (INIS)

    Lee, Chunwoo; Batchelor, Bill; Park, Sung Hyuk; Han, Dong Suk; Abdel-Wahab, Ahmed; Kramer, Timothy A.

    2011-01-01

    Highlights: ► ZVT is oxidized during electrochemically induced pitting corrosion to produce reactive soluble species. ► Perchlorate is effectively reduced to chloride by soluble titanium species. ► Solution pH and surface area of ZVT showed negligible effects on rates of perchlorate reduction. - Abstract: Zero-valent metals and ionic metal species are a popular reagent for the abatement of contaminants in drinking water and groundwater and perchlorate is a contaminant of increasing concern. However, perchlorate degradation using commonly used reductants such as zero-valent metals and soluble reduced metal species is kinetically limited. Titanium in the zero-valent and soluble states has a high thermodynamic potential to reduce perchlorate. Here we show that perchlorate is effectively reduced to chloride by soluble titanium species in a system where the surface oxide film is removed from ZVT and ZVT is oxidized during electrochemically induced pitting corrosion to produce reactive soluble species. The pitting potential of ZVT was measured as 12.77 ± 0.04 V (SHE) for a 100 mM solution of perchlorate. The rate of perchlorate reduction was independent of the imposed potential as long as the potential was maintained above the pitting potential, but it was proportional to the applied current. Solution pH and surface area of ZVT electrodes showed negligible effects on rates of perchlorate reduction. Although perchlorate is effectively reduced during electrochemically induced corrosion of ZVT, this process may not be immediately applicable to perchlorate treatment due to the high potentials needed to produce active reductants, the amount of titanium consumed, the inhibition of perchlorate removal by chloride, and oxidation of chloride to chlorine.

  7. In situ vitrification demonstration at Pit 1, Oak Ridge National Laboratory. Volume 2: Site characterization report of the Pit 1 area

    International Nuclear Information System (INIS)

    Spalding, B.P.; Bogle, M.A.; Cline, S.R.; Naney, M.T.; Gu, B.

    1997-12-01

    A treatability study was initiated in October 1993, initially encompassing the application of in situ vitrification (ISV) to at least two segments of Oak Ridge National Laboratory (ORNL) seepage Pit 1 by the end of fiscal year (FY) 1995. This treatability study was to have supported a possible Interim Record of Decision (IROD) or removal action for closure of one or more of the seepage pits and trenches as early as FY 1997. The Remedial Investigation/Feasibility Study for Waste Area Grouping (WAG) 7, which contains these seven seepage pits and trenches, will probably not begin until after the year 2000. This treatability study will establish the field-scale technical performance of ISV for (1) attaining the required depth, nominally 15 ft, to incorporate source contamination within and beneath the pits; (2) demonstrating field capability to overlap melt settings that are necessary to achieve fused, melted segments of the source contamination; (3) demonstrating off-gas handling technology for accommodating and minimizing the volatilization of 137 Cs; (4) demonstrating adequate site characterization techniques to predict ISV melting kinetics, processing temperatures, and product durability; and (5) promoting public acceptance of ISV technology by demonstrating its safety, implementability, site impacts, and air emissions and by coordinating the treatability study within the regulatory closure process. This report summarizes the site characterization information gathered through the end of September 1996 which supports the planning and assessment of ISV for Pit 1 (objective 4 above)

  8. In situ vitrification demonstration at Pit 1, Oak Ridge National Laboratory. Volume 2: Site characterization report of the Pit 1 area

    Energy Technology Data Exchange (ETDEWEB)

    Spalding, B.P.; Bogle, M.A.; Cline, S.R.; Naney, M.T.; Gu, B.

    1997-12-01

    A treatability study was initiated in October 1993, initially encompassing the application of in situ vitrification (ISV) to at least two segments of Oak Ridge National Laboratory (ORNL) seepage Pit 1 by the end of fiscal year (FY) 1995. This treatability study was to have supported a possible Interim Record of Decision (IROD) or removal action for closure of one or more of the seepage pits and trenches as early as FY 1997. The Remedial Investigation/Feasibility Study for Waste Area Grouping (WAG) 7, which contains these seven seepage pits and trenches, will probably not begin until after the year 2000. This treatability study will establish the field-scale technical performance of ISV for (1) attaining the required depth, nominally 15 ft, to incorporate source contamination within and beneath the pits; (2) demonstrating field capability to overlap melt settings that are necessary to achieve fused, melted segments of the source contamination; (3) demonstrating off-gas handling technology for accommodating and minimizing the volatilization of {sup 137}Cs; (4) demonstrating adequate site characterization techniques to predict ISV melting kinetics, processing temperatures, and product durability; and (5) promoting public acceptance of ISV technology by demonstrating its safety, implementability, site impacts, and air emissions and by coordinating the treatability study within the regulatory closure process. This report summarizes the site characterization information gathered through the end of September 1996 which supports the planning and assessment of ISV for Pit 1 (objective 4 above).

  9. Gamma-ray and surface organic results of the robotic survey of Pit 9 at INEL

    International Nuclear Information System (INIS)

    Clegg, B.; Rowland, M.; Pence, J.

    1991-09-01

    The Buried Waste Robotics Program demonstrated and evaluated robotic techniques to non-invasively characterize a representative radiological burial area at the Idaho National Engineering Laboratory (ML). Lawrence Livermore National Laboratory (LLNL) contributed a large, NaI gamma-ray detector system and a photo-ionization organics detector to this program. This Program mounted multiple geophysics, nucleonic, and chemical sensor systems on the Solder Robot Interface Program (SRIP) remotely operated vehicle. These sensors simultaneously collected radiological waste-site, surface characterization data on Pit 9 radiological burial area, and the Cold Test Pit (CTP), off-site control area. LLNL sensors found no radiological waste at the CTP control area, however, we easily detected the natural thorium series, the potassium radionuclides and trace worldwide fallout cesium. Earlier manual measurements indicated no significant data error invoked by the vehicle on our gamma-ray and organic sensor systems. Thick soil overburden at the Subsurface Disposal Area (SDA), Pit 9, permitted radiological, but no isotopic determinations. A flood of scattered photons from the buried waste allows a surface, spatial radiological dose assessment. We found no evidence of surface-evolving organics, sensitive to photo-ionization detection. The observed signals can safely guide a remediation excavation. The vehicle-supported multiple measurements enhanced the data collection efficiency. Data provided site-surface characterization, quickly and safely in potentially hazardous areas. However, a large, buried-waste site will require subsurface access for detailed characterization

  10. Metallic elements fractionation in municipal solid waste incineration residues

    Science.gov (United States)

    Kowalski, Piotr R.; Kasina, Monika; Michalik, Marek

    2016-04-01

    Municipal solid waste incineration (MSWI) residues are represented by three main materials: bottom ash, fly ash and air pollution control (APC) residues. Among them ˜80 wt% is bottom ash. All of that materials are products of high temperature (>1000° C) treatment of waste. Incineration process allows to obtain significant reduction of waste mass (up to 70%) and volume (up to 90%) what is commonly used in waste management to reduce the amount need to be landfilled or managed in other way. Incineration promote accumulation non-combustible fraction of waste, which part are metallic elements. That type of concentration is object of concerns about the incineration residues impact on the environment and also gives the possibility of attempts to recover them. Metallic elements are not equally distributed among the materials. Several factors influence the process: melting points, volatility and place and forms of metallic occurrence in the incinerated waste. To investigate metallic elements distribution in MSWI residues samples from one of the biggest MSW incineration plant in Poland were collected in 2015. Chemical analysis with emphasis on the metallic elements content were performed using inductively coupled plasma optical emission (ICP-OES) and mass spectrometry (ICP-MS). The bottom ash was a SiO2-CaO-Al2O3-Fe2O3-Na2O rich material, whereas fly ash and APC residues were mostly composed of CaO and SiO2. All of the materials were rich in amorphous phase occurring together with various, mostly silicate crystalline phases. In a mass of bottom ash 11 wt% were metallic elements but also in ashes 8.5 wt% (fly ash) and ˜4.5 wt% (APC residues) of them were present. Among the metallic elements equal distribution between bottom and fly ash was observed for Al (˜3.85 wt%), Mn (770 ppm) and Ni (˜65 ppm). In bottom ash Fe (5.5 wt%), Cr (590 ppm) and Cu (1250 ppm) were concentrated. These values in comparison to fly ash were 5-fold higher for Fe, 3-fold for Cu and 1.5-fold for

  11. Process and equipment qualification of the ceramic and metal waste forms for spent fuel treatment

    International Nuclear Information System (INIS)

    Marsden, Ken; Knight, Collin; Bateman, Kenneth; Westphal, Brian; Lind, Paul

    2005-01-01

    The electrometallurgical process for treating sodium-bonded spent metallic fuel at the Materials and Fuels Complex of the Idaho National Laboratory separates actinides and partitions fission products into two waste forms. The first is the metal waste form, which is primarily composed of stainless steel from the fuel cladding. This stainless steel is alloyed with 15w% zirconium to produce a very corrosion-resistant metal which binds noble metal fission products and residual actinides. The second is the ceramic waste form which stabilizes fission product-loaded chloride salts in a sodalite and glass composite. These two waste forms will be packaged together for disposal at the Yucca Mountain repository. Two production-scale metal waste furnaces have been constructed. The first is in a large argon-atmosphere glovebox and has been used for equipment qualification, process development, and process qualification - the demonstration of process reliability for production of the DOE-qualified metal waste form. The second furnace will be transferred into a hot cell for production of metal waste. Prototype production-scale ceramic waste equipment has been constructed or procured; some equipment has been qualified with fission product-loaded salt in the hot cell. Qualification of the remaining equipment with surrogate materials is underway. (author)

  12. A Theoretical Model for Metal Corrosion Degradation

    Directory of Open Access Journals (Sweden)

    David V. Svintradze

    2010-01-01

    Full Text Available Many aluminum and stainless steel alloys contain thin oxide layers on the metal surface which greatly reduce the corrosion rate. Pitting corrosion, a result of localized breakdown of such films, results in accelerated dissolution of the underlying metal through pits. Many researchers have studied pitting corrosion for several decades and the exact governing equation for corrosion pit degradation has not been obtained. In this study, the governing equation for corrosion degradation due to pitting corrosion behavior was derived from solid-state physics and some solutions and simulations are presented and discussed.

  13. Metal leaching from refinery waste hydroprocessing catalyst.

    Science.gov (United States)

    Marafi, Meena; Rana, Mohan S

    2018-05-18

    The present study aims to develop an eco-friendly methodology for the recovery of nickel (Ni), molybdenum (Mo), and vanadium (V) from the refinery waste spent hydroprocessing catalyst. The proposed process has two stages: the first stage is to separate alumina, while the second stage involves the separation of metal compounds. The effectiveness of leaching agents, such as NH 4 OH, (NH 4 ) 2 CO 3 , and (NH 4 ) 2 S 2 O 8 , for the extraction of Mo, V, Ni, and Al from the refinery spent catalyst has been reported as a function of reagent concentration (0.5 to 2.0 molar), leaching time (1 to 6 h), and temperature (35 to 60°C). The optimal leaching conditions were achieved to obtain the maximum recovery of Mo, Ni, and V metals. The effect of the mixture of multi-ammonium salts on the metal extraction was also studied, which showed an adverse effect for Ni and V, while marginal improvement was observed for Mo leaching. The ammonium salts can form soluble metal complexes, in which stability or solubility depends on the nature of ammonium salt and the reaction conditions. The extracted metals and support can be reused to synthesize a fresh hydroprocessing catalyst. The process will reduce the refinery waste and recover the expensive metals. Therefore, the process is not only important from an environmental point of view but also vital from an economic perspective.

  14. Remaining Sites Verification Package for the 126-B-3, 184-B Coal Pit Dumping Area, Waste Site Reclassification Form 2005-028

    Energy Technology Data Exchange (ETDEWEB)

    L. M. Dittmer

    2006-08-07

    The 126-B-3 waste site is the former coal storage pit for the 184-B Powerhouse. During demolition operations in the 1970s, the site was used for disposal of demolition debris from 100-B/C Area facilities. The site has been remediated by removing debris and contaminated soils. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River.

  15. Method of decontaminating radioactive metal wastes

    International Nuclear Information System (INIS)

    Miyaji, Nobuyoshi.

    1985-01-01

    Purpose: To completely prevent the surface contamination of an equipment and decrease the amount of radioactive wastes to be resulted. Method: The surfaces of vessels, pipeways or the likes of nuclear reactor facilities to be contaminated with radioactive materials are appended with thin plates of metals identical or different from the constituents of the surfaces so as to be releasable after use. The material and the thickness of the plates and the method of appending then are determined depending on the state of use of the appended portions. Since only the stripped plates have to be processed as radioactive wastes, the amount of wastes can be decreased and, since the scrap materials can be reused, it is advantageous in view of the resource-saving. (Sekiya, K.)

  16. Reducing the leachability of nitrate, phosphorus and heavy metals from soil using waste material

    Directory of Open Access Journals (Sweden)

    Faridullah

    Full Text Available Abstract Contaminants like nitrate (NO3, phosphorus (P and heavy metals in water are often associated with agricultural activities. Various soil and water remediation techniques have been employed to reduce the risk associated with these contaminants. A study was conducted to examine the extent of leaching of heavy metals (Cd, Ni, Pb and Cr, NO3 and P. For this purpose sandy and silt loam soils were amended with different waste materials, namely wood ash, solid waste ash, vegetable waste, charcoal, and sawdust. The soils were saturated with wastewater. Irrespective of the waste applied, the pH and EC of the amended soils were found to be greater than the control. Charcoal, sawdust and wood ash significantly decreased heavy metals, nitrate and phosphorus concentrations in the leachate. Treatments were more efficient for reducing Ni than other heavy metals concentrations. Waste amendments differed for heavy metals during the process of leaching. Heavy metals in the soil were progressively depleted due to the successive leaching stages. This research suggests that waste material may act as an adsorbent for the above contaminants and can reduce their leachability in soils.

  17. CJSC ECOMET-S facility for reprocessing and utilisation of radioactive metal waste: operating experience

    International Nuclear Information System (INIS)

    Gelbutovsky, A.B.; Kishkin, S.A.; Mochenov, M.I.; Troshev, A.V.; Cheremisin, P.I.; Chernichenko, A.A.

    2006-01-01

    The principal objective of the paper is to present operating experience in management of radioactive metal waste, originating at nuclear power facilities of the Russian Federation. Issues of radioactive metal waste recycling by melting, with the purpose of unrestricted re-use in industry, or restricted re-use within the nuclear industry, have been considered. The necessity for using a method of melting at the final stage of radioactive metal waste recycling has been proved. Priority measures to be taken and results achieved in the implementation of the Governmental purpose-oriented programme 'Radioactive Metal Waste Reprocessing and Utilization' have been considered, the CJSC ECOMET-S being the main contractor on the Programme. Main specifications and results of operating a commercial melting facility, owned by CJSC 'ECOMET-S' and used to recycle low-level radioactive metal waste originated at the Leningrad Nuclear Power Plant, have been presented. (author)

  18. Numerical Simulation of Interactions between Corrosion Pits on Stainless Steel under Loading Conditions

    International Nuclear Information System (INIS)

    Wang, Haitao; Han, En-Hou

    2017-01-01

    The interactions between corrosion pits on stainless steel under loading conditions are studied by using a cellular automata model coupled with finite element method at a mesoscopic scale. The cellular automata model focuses on a metal/film/electrolyte system, including anodic dissolution, passivation, diffusion of hydrogen ions and salt film hydrolysis. The Chopard block algorithm is used to improve the diffusion simulation efficiency. The finite element method is used to calculate the stress concentration on the pit surface during pit growth, and the effect of local stress and strain on anodic current is obtained by using the Gutman model, which is used as the boundary conditions of the cellular automata model. The transient current characteristics of the interactions between corrosion pits under different simulation factors including the breakdown of the passive film at the pit mouth and the diffusion of hydrogen ions are analyzed. The analysis of the pit stability product shows that the simulation results are close to the experimental conclusions.

  19. Numerical Simulation of Interactions between Corrosion Pits on Stainless Steel under Loading Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Haitao; Han, En-Hou [Chinese Academy of Sciences, Shenyang (China)

    2017-04-15

    The interactions between corrosion pits on stainless steel under loading conditions are studied by using a cellular automata model coupled with finite element method at a mesoscopic scale. The cellular automata model focuses on a metal/film/electrolyte system, including anodic dissolution, passivation, diffusion of hydrogen ions and salt film hydrolysis. The Chopard block algorithm is used to improve the diffusion simulation efficiency. The finite element method is used to calculate the stress concentration on the pit surface during pit growth, and the effect of local stress and strain on anodic current is obtained by using the Gutman model, which is used as the boundary conditions of the cellular automata model. The transient current characteristics of the interactions between corrosion pits under different simulation factors including the breakdown of the passive film at the pit mouth and the diffusion of hydrogen ions are analyzed. The analysis of the pit stability product shows that the simulation results are close to the experimental conclusions.

  20. A New Algorithm for Determining Ultimate Pit Limits Based on Network Optimization

    Directory of Open Access Journals (Sweden)

    Ali Asghar Khodayari

    2013-12-01

    Full Text Available One of the main concerns of the mining industry is to determine ultimate pit limits. Final pit is a collection of blocks, which can be removed with maximum profit while following restrictions on the slope of the mine’s walls. The size, location and final shape of an open-pit are very important in designing the location of waste dumps, stockpiles, processing plants, access roads and other surface facilities as well as in developing a production program. There are numerous methods for designing ultimate pit limits. Some of these methods, such as floating cone algorithm, are heuristic and do not guarantee to generate optimum pit limits. Other methods, like Lerchs–Grossmann algorithm, are rigorous and always generate the true optimum pit limits. In this paper, a new rigorous algorithm is introduced. The main logic in this method is that only positive blocks, which can pay costs of their overlying non-positive blocks, are able to appear in the final pit. Those costs may be paid either by positive block itself or jointly with other positive blocks, which have the same overlying negative blocks. This logic is formulated using a network model as a Linear Programming (LP problem. This algorithm can be applied to two- and three-dimension block models. Since there are many commercial programs available for solving LP problems, pit limits in large block models can be determined easily by using this method.

  1. Micro pit formation by mercury-sphere collision

    International Nuclear Information System (INIS)

    Ishikura, Syuichi; Kogawa, Hiroyuki; Futakawa, Masatoshi; Kaminaga, Masanori; Hino, Ryutaro

    2004-01-01

    The development of a MW-class spallation neutron source facility is being carried out under the Japan Proton Accelerator Research Complex (J-PARC) Project promoted by JAERI and KEK. A mercury target working as the spallation neutron source will be subjected to pressure waves generated by rapid thermal expansion of mercury due to a pulsed proton beam injection. The pressure wave will impose dynamic stress on the vessel and deform the vessel, which would cause cavitation in mercury. To evaluate the effect of mercury micro jets, driven by cavitation bubble collapse, on the micro-pit formation, analyses on mercury sphere collision were carried out: single bubble dynamics and collision behavior on interface between liquid and solid, which take the nonlinearity due to shock wave in mercury and the strain rate dependency of yield stress in solid metal into account. Analytical results give a good explanation to understand relationship between the micro-pit formation and material properties: the pit size could decrease with increasing the yield strength of materials. (author)

  2. Pitting Corrosion of the Resistance Welding Joints of Stainless Steel Ventilation Grille Operated in Swimming Pool Environment

    Directory of Open Access Journals (Sweden)

    Mirosław Szala

    2018-01-01

    Full Text Available This work focuses on the pitting corrosion of ventilation grilles operated in swimming pool environments. The ventilation grille was made by resistance welding of stainless steel rods. Based on the macroscopic and microscopic examinations, the mechanism of the pitting corrosion was confirmed. Chemical composition microanalysis of sediments as well as base metal using scanning electron microscopy and energy-dispersive spectroscopy (SEM-EDS method was carried out. The weldments did not meet the operating conditions of the swimming pool environment. The wear due to the pitting corrosion was identified in heat affected zones of stainless steel weldment and was more severe than the corrosion of base metal. The low quality finish of the joints and influence of the welding process on the weld metal microstructure lead to accelerated deposition of corrosion effecting elements such as chlorine.

  3. Metal Poisons for Criticality in Waste Streams

    International Nuclear Information System (INIS)

    Williamson, T.G.; Goslen, A.Q.

    1996-01-01

    Many of the wastes from processing fissile materials contain metals which may serve as nuclear criticality poisons. It would be advantageous to the criticality evaluation of these wastes to demonstrate that the poisons remain with the fissile materials and to demonstrate an always safe poison-to-fissile ratio. The first task, demonstrating that the materials stay together, is the job of the chemist, the second, calculating an always safe ratio, is an object of this paper

  4. The study of heavy metals leaching from waste foundry sands using a one-step extraction

    Science.gov (United States)

    Bożym, Marta

    2017-10-01

    There are a number of leaching test which are used to evaluate the effect of foundry waste disposal on the environment (TCLP, SPLP, ASTM at al.). Because the spent foundry sand are usually deposited at the ground level and they have a similar structure to the soil, survey mobility of metals using the same methods seems appropriate. One-step extraction allows for the evaluation of the mobility and bioavailability of metals in soil and waste. Waste foundry sands have been successfully used as a component in manufactured soils in U.S., but concern over metal contamination must be eliminated before considering this direction of use. The study evaluated the leaching of heavy metals (Cd, Pb, Cu, Zn, Cr, Ni) from deposited waste foundry sands. The overall, as well as heavy metals were extracted by different type of extractants: H2O, CH3COOH, HCl, EDTA, MgCl2 and NaCOOH. These extractants are most commonly used to study the mobility and bioavailability of metals in soil and waste. In the present study applicable standards and methodology described in the literature in analysis were used. The results allowed to evaluate the bioavailability of metals leached from those wastes.

  5. Quality Assurance Project Plan for the treatability study of in situ vitrification of Seepage Pit 1 in Waste Area Grouping 7 at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    1995-07-01

    This Quality Assurance Project Plan (QAPjP) establishes the quality assurance procedures and requirements to be implemented for the control of quality-related activities for Phase 3 of the Treatability Study (TS) of In Situ Vitrification (ISV) of Seepage Pit 1, ORNL Waste Area Grouping 7. This QAPjP supplements the Quality Assurance Plan for Oak Ridge National Laboratory Environmental Restoration Program by providing information specific to the ISV-TS. Phase 3 of the TS involves the actual ISV melt operations and posttest monitoring of Pit 1 and vicinity. Previously, Phase 1 activities were completed, which involved determining the boundaries of Pit 1, using driven rods and pipes and mapping the distribution of radioactivity using logging tools within the pipes. Phase 2 involved sampling the contents, both liquid and solids, in and around seepage Pit 1 to determine their chemical and radionuclide composition and the spatial distribution of these attributes. A separate QAPjP was developed for each phase of the project. A readiness review of the Phase 3 activities presented QAPjP will be conducted prior to initiating field activities, and an Operational Acceptance, Test (OAT) will also be conducted with no contamination involved. After, the OAT is complete, the ISV process will be restarted, and the melt will be allowed to increase with depth and incorporate the radionuclide contamination at the bottom of Pit 1. Upon completion of melt 1, the equipment will be shut down and mobilized to an adjacent location at which melt 2 will commence

  6. Devoluming method and device for radioactive metal wastes containing zirconium alloy

    International Nuclear Information System (INIS)

    Komatsu, Masahiko; Wada, Ryutaro.

    1996-01-01

    The present invention concerns a method of sealing radioactive metal wastes in a capsule and compressing the capsule for devoluming treatment. The method comprises a step of carrying radioactive metal wastes into a sealed chamber having a capacity somewhat greater than that of the capsule, a deaerating step of sucking the air in the sealed chamber to attain a substantially vacuum state, a compression-devoluming step of compression-devoluming the capsule by reducing the volume of the sealed chamber and a transporting step of transporting the devolumed capsule from the sealed chamber. The sealed chamber to which the capsule incorporated with radioactive metal wastes containing a zirconium alloy is carried is then deaerated into a substantially vacuum state. Even if ignitable powdery dusts are generated from the radioactive metal wastes crushed by compression-devoluming of the capsule in the succeeding compression-devoluming step, since the air necessary for ignition is not present, ignition of the powdery dusts is prevented. Alternatively, since the inside of the sealed chamber is filled with an inert gas, ignition of the powdery dusts can effectively be prevented. (N.H.)

  7. Waste printing paper as analogous adsorbents for heavy metals in ...

    African Journals Online (AJOL)

    user

    heavy metals uptake from aqueous solutions but the recovery efficacy as economic and environmental ... system. 1 . Wastes containing metals are directly or indirectly discharge into the environment ... According to World health Organization. 5.

  8. The resistance of austenitic stainless steels to pitting corrosion in simulated BFS/OPC pore waters containing thiosulphate ions

    International Nuclear Information System (INIS)

    Betts, A.J.; Newman, R.C.

    1989-06-01

    Current plans for the disposal of intermediate-level nuclear waste involve the use of austenitic stainless steel drums. The immediate environment seen by both the inner and outer surfaces of these drums will be alkaline, as a consequence of the encasement of both the drum and its contents in concrete. Normally there would be no risk of localized corrosion of the steel in this situation, but a possible complication is introduced by the use of blast-furnace slag (BFS) to decrease the permeability of the concrete. Metal sulphides in the BFS react with air and water to yield thiosulphate ions, which are known to be corrosive towards stainless steels in environments of near-neutral pH. This research was carried out to study the effects of thiosulphate at alkaline pH, simulating the concrete environment. Types 304L and 316L stainless steel have been tested for pitting corrosion resistance in simulated BFS/Ordinary Portland Cement pore waters of pH 10-13, at 20 o C and 50 o C. The results show that the 316L steel is essentially immune to pitting. The 304L steel shows some pitting at the higher temperature, especially at the higher chloride concentrations, but only at pH values of less than 12, which would require serious deterioration of the cement matrix. (author)

  9. Plant succession patterns on residual open-pit gravel mines deposits Bogota

    OpenAIRE

    Ricardo A. Mora Goyes

    1999-01-01

    Based on both: the study of composition and structure of plant communities and the analysis of the physico-chemical characteristics of mining wastes, the initial patterns of primary succession were determined. These patterns were present in three deposits of waste material abandoned during 18, 36 and 120 months respectively. Sue materials were originated in open-pit gravel mines located to the south of Bogota (Colombia). This study pretends to contribute to the knowledge of the meehanlsms of ...

  10. Embedding methods of solidified waste in metal matrices

    International Nuclear Information System (INIS)

    Neumann, W.

    1979-01-01

    The embedding of simulated waste calcines by three different methods (vacuum-pressure casting, centrifugal casting, and metal stirred with the calcines) was investigated. The experimental performance is described and advantages and disadvantages noted. The feasibility of embedding fines by stirring in metal was shown. In addition, an estimation of the influence of porosity on the properties of composites was carried out

  11. THE INFLUENCE OF SELECTED FACTORS ON THE LEACHING OF HEAVY METALS FROM SMELTER WASTE

    Directory of Open Access Journals (Sweden)

    Kamila Mizerna

    2015-07-01

    Full Text Available The paper presents the results of leaching research of selected heavy metals (Pb, Cu, Zn, Ni, Cd, Cr from industrial waste. The impact of waste fragmentation on the level of heavy metals leaching was analyzed. The decrease of copper and zinc release and the increase of nickel leaching were observed with increasing grain size fraction of waste. Furthermore, release of contaminants in different ratio of liquid to solid (L/S = 10 dm3/kg and 2 dm3/kg was studied. Higher concentrations of heavy metals were determined in ratio of L/S = 10 dm3/kg. In order to determine the risk of tested waste to the environment, the results were compared with the current law. This allowed the classification of the waste to hazardous waste.

  12. The study on recycle scheme of the metallic radioactive wastes (II)

    International Nuclear Information System (INIS)

    Shin, J. I.; Park, J. H.; Jung, K. J.

    2003-01-01

    It was understood that regulation criteria for material release varied with countries and that international standards were not setup. But, most advanced countries are continuously studying on the recycling of metallic wastes for the purpose of the reuse of resources and disposal cost reduction. Practically, the advanced countries make a lot of cost profits compared with disposal as their metallic wastes are recycled and reused through technology like melting. The reasonable international standards are also expected to be set in the near future because of the aggressive cooperation between international agencies such as IAEA and NEA toward recycling these wastes. In our case, the recycle criteria for radioactive waste containing radioactive nuclide with long half-life such as Cs-137(half-life: 30y) and Co-60(half-life: 5.26y) including others, which are generated from the nuclear fission or dismantling of nuclear facilities, are not yet established. Therefore, it is required that the recommendation and legalization of the regulatory criteria be carried out for the recycle and reuse of metallic wastes to be generated from the dismantling of domestic nuclear facilities in the future

  13. Analysis of the application of decontamination technologies to radioactive metal waste minimization using expert systems

    Energy Technology Data Exchange (ETDEWEB)

    Bayrakal, Suna [Iowa State Univ., Ames, IA (United States)

    1993-09-30

    Radioactive metal waste makes up a significant portion of the waste currently being sent for disposal. Recovery of this metal as a valuable resource is possible through the use of decontamination technologies. Through the development and use of expert systems a comparison can be made of laser decontamination, a technology currently under development at Ames Laboratory, with currently available decontamination technologies for applicability to the types of metal waste being generated and the effectiveness of these versus simply disposing of the waste. These technologies can be technically and economically evaluated by the use of expert systems techniques to provide a waste management decision making tool that generates, given an identified metal waste, waste management recommendations. The user enters waste characteristic information as input and the system then recommends decontamination technologies, determines residual contamination levels and possible waste management strategies, carries out a cost analysis and then ranks, according to cost, the possibilities for management of the waste. The expert system was developed using information from literature and personnel experienced in the use of decontamination technologies and requires validation by human experts and assignment of confidence factors to the knowledge represented within.

  14. Analysis of the application of decontamination technologies to radioactive metal waste minimization using expert systems

    International Nuclear Information System (INIS)

    Bayrakal, S.

    1993-01-01

    Radioactive metal waste makes up a significant portion of the waste currently being sent for disposal. Recovery of this metal as a valuable resource is possible through the use of decontamination technologies. Through the development and use of expert systems a comparison can be made of laser decontamination, a technology currently under development at Ames Laboratory, with currently available decontamination technologies for applicability to the types of metal waste being generated and the effectiveness of these versus simply disposing of the waste. These technologies can be technically and economically evaluated by the use of expert systems techniques to provide a waste management decision making tool that generates, given an identified metal waste, waste management recommendations. The user enters waste characteristic information as input and the system then recommends decontamination technologies, determines residual contamination levels and possible waste management strategies, carries out a cost analysis and then ranks, according to cost, the possibilities for management of the waste. The expert system was developed using information from literature and personnel experienced in the use of decontamination technologies and requires validation by human experts and assignment of confidence factors to the knowledge represented within

  15. Treatment of a mud pit by bioremediation.

    Science.gov (United States)

    Avdalović, Jelena; Đurić, Aleksandra; Miletić, Srdjan; Ilić, Mila; Milić, Jelena; Vrvić, Miroslav M

    2016-08-01

    The mud generated from oil and natural gas drilling, presents a considerable ecological problem. There are still insufficient remedies for the removal and minimization of these very stable emulsions. Existing technologies that are in use, more or less successfully, treat about 20% of generated waste drilling mud, while the rest is temporarily deposited in so-called mud pits. This study investigated in situ bioremediation of a mud pit. The bioremediation technology used in this case was based on the use of naturally occurring microorganisms, isolated from the contaminated site, which were capable of using the contaminating substances as nutrients. The bioremediation was stimulated through repeated inoculation with a zymogenous microbial consortium, along with mixing, watering and biostimulation. Application of these bioremediation techniques reduced the concentration of total petroleum hydrocarbons from 32.2 to 1.5 g kg(-1) (95% degradation) during six months of treatment. © The Author(s) 2016.

  16. The study of heavy metals leaching from waste foundry sands using a one-step extraction

    Directory of Open Access Journals (Sweden)

    Bożym Marta

    2017-01-01

    Full Text Available There are a number of leaching test which are used to evaluate the effect of foundry waste disposal on the environment (TCLP, SPLP, ASTM at al.. Because the spent foundry sand are usually deposited at the ground level and they have a similar structure to the soil, survey mobility of metals using the same methods seems appropriate. One-step extraction allows for the evaluation of the mobility and bioavailability of metals in soil and waste. Waste foundry sands have been successfully used as a component in manufactured soils in U.S., but concern over metal contamination must be eliminated before considering this direction of use. The study evaluated the leaching of heavy metals (Cd, Pb, Cu, Zn, Cr, Ni from deposited waste foundry sands. The overall, as well as heavy metals were extracted by different type of extractants: H2O, CH3COOH, HCl, EDTA, MgCl2 and NaCOOH. These extractants are most commonly used to study the mobility and bioavailability of metals in soil and waste. In the present study applicable standards and methodology described in the literature in analysis were used. The results allowed to evaluate the bioavailability of metals leached from those wastes.

  17. Preliminary study on recycling of metallic waste from decommissioning of nuclear power plant for cask

    International Nuclear Information System (INIS)

    Ohe, Koichiro; Kato, Osamu; Saegusa, Toshiari

    1999-01-01

    Preliminary study was made on technology required to recycle of metallic waste from decommissioning for spent fuel storage cask and on quantity of the cask which can be produced by the metallic waste. The technical and institutional issues for the recycling were studied. The metallic waste from decommissioning may be technically used to a certain degree for manufacturing the casks. However, there were some technical issues to be solved. For example, the manufacturing factories should be established. The radioactive waste from the factories with radiation control should be handled and treated carefully. Quality of the cask should be properly controlled. The 'Clearance Levels' which allows to recycle decommissioning waste have been hardly enacted in Japan. Technical and economic evaluation on recycling of metallic waste from decommissioning for spent fuel storage cask should be conducted again after progress in recycling of radioactive waste of which radioactivity is below the 'Clearance Levels' in Japan. (author)

  18. Selection of barrier metals for a waste package in tuff

    International Nuclear Information System (INIS)

    Russell, E.W.; McCright, R.D.; O'Neal, W.C.

    1983-09-01

    The Nevada Nuclear Waste Storage Investigation (NNWSI) project under the Civilian Radioactive Waste Management Program is planning a repository at Yucca Mountain at the Nevada Test Site for isolation of high-level nuclear waste. LLNL is developing designs for an engineered barrier system containing several barriers such as the waste form, a canister and/or an overpack, packing, and near field host rock. The selection of metal containment barriers is addressed. 13 references

  19. Children with health impairments by heavy metals in an e-waste recycling area

    NARCIS (Netherlands)

    Zeng, Xiang; Xu, Xijin; Boezen, H. Marike; Huo, Xia

    E-waste recycling has become a global environmental health issue. Pernicious chemicals escape into the environment due to informal and nonstandard e-waste recycling activities involving manual dismantling, open burning to recover heavy metals and open dumping of residual fractions. Heavy metals

  20. Sizing and melting development activities using noncontaminated metal at the Waste Experimental Reduction Facility

    International Nuclear Information System (INIS)

    Larsen, M.M.; Logan, J.A.

    1984-05-01

    EG and G Idaho, Inc., has established the Waste Experimental Reduction Facility (WERF) at the Idaho National Engineering Laboratory (INEL) to develop the capability to reduce the volume that low-level beta/gamma wastes occupy at the disposal site. The work effort at WERF includes a waste sizing development activity (WSDA), a waste melting development activity (WMDA), and a waste incineration development activity (WIDA). This report describes work and developments to date in the WSDA and WMDA with noncontaminated metallic waste in preparation for operations at WERF involving beta/gamma-contaminated metal

  1. TREATMENT OF METAL-LADEN HAZARDOUS WASTES WITH ADVANCED CLEAN COAL TECHNOLOGY BY-PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    James T. Cobb, Jr.

    2003-09-12

    Metal-laden wastes can be stabilized and solidified using advanced clean coal technology by-products (CCTBs)--fluid bed combustor ash and spray drier solids. These utility-generated treatment chemicals are available for purchase through brokers, and commercial applications of this process are being practiced by treaters of metal-laden hazardous waste. A complex of regulations governs this industry, and sensitivities to this complex has discouraged public documentation of treatment of metal-laden hazardous wastes with CCTBs. This report provides a comprehensive public documentation of laboratory studies that show the efficacy of the stabilization and solidification of metal-laden hazardous wastes--such as lead-contaminated soils and sandblast residues--through treatment with CCTBs. It then describes the extensive efforts that were made to obtain the permits allowing a commercial hazardous waste treater to utilize CCTBs as treatment chemicals and to install the equipment required to do so. It concludes with the effect of this lengthy process on the ability of the treatment company to realize the practical, physical outcome of this effort, leading to premature termination of the project.

  2. Development for recycle of dismantled metal wastes by decommissioning of NPP

    International Nuclear Information System (INIS)

    Asami, Tomohiro; Sato, Hiroshi; Hatakeyama, Mutsuo

    2007-01-01

    For recycle of dismantled metal wastes generated by the decommissioning of nuclear power plant, we examined a melting test for melting characterization of stainless steel scrap, designed the conceptual process to produce the recycle products, and developed a recycle cost evaluation code which is useful to make a rational planning for the waste management program (cost, determination of process, etc.) of these metal wastes. This report gives the summary of these development carried out from 2001 to 2005. This work was performed under the sponsorship of Ministry of Education, Culture, Sports, Science and Technology of Japan. (author)

  3. Mitigated Transfer Line Leaks that Result in Surface Pools and Spray Leaks into Pits

    Energy Technology Data Exchange (ETDEWEB)

    HEY, B.E.

    1999-12-07

    This analysis provides radiological and toxicological consequence calculations for postulated mitigated leaks during transfers of six waste compositions. Leaks in Cleanout Boxes equipped with supplemental covers and leaks in pits are analyzed.

  4. Mitigated Transfer Line Leaks that Result in Surface Pools and Spray Leaks into Pits

    International Nuclear Information System (INIS)

    HEY, B.E.

    1999-01-01

    This analysis provides radiological and toxicological consequence calculations for postulated mitigated leaks during transfers of six waste compositions. Leaks in Cleanout Boxes equipped with supplemental covers and leaks in pits are analyzed

  5. Geologic report for the Weldon Spring Raffinate Pits Site

    International Nuclear Information System (INIS)

    1984-10-01

    A preliminary geologic site characterization study was conducted at the Weldon Spring Raffinate Pits Site, which is part of the Weldon Spring Site, in St. Charles County, Missouri. The Raffinate Pits Site is under the custody of the Department of Energy (DOE). Surrounding properties, including the Weldon Spring chemical plant, are under the control of the Department of the Army. The study determined the following parameters: site stratigraphy, lithology and general conditions of each stratigraphic unit, and groundwater characteristics and their relation to the geology. These parameters were used to evaluate the potential of the site to adequately store low-level radioactive wastes. The site investigation included trenching, geophysical surveying, borehole drilling and sampling, and installing observation wells and piezometers to monitor groundwater and pore pressures

  6. Heavy metal contamination of surface soil in electronic waste dismantling area: site investigation and source-apportionment analysis.

    Science.gov (United States)

    Jinhui Li; Huabo Duan; Pixing Shi

    2011-07-01

    The dismantling and disposal of electronic waste (e-waste) in developing countries is causing increasing concern because of its impacts on the environment and risks to human health. Heavy-metal concentrations in the surface soils of Guiyu (Guangdong Province, China) were monitored to determine the status of heavy-metal contamination on e-waste dismantling area with a more than 20 years history. Two metalloids and nine metals were selected for investigation. This paper also attempts to compare the data among a variety of e-waste dismantling areas, after reviewing a number of heavy-metal contamination-related studies in such areas in China over the past decade. In addition, source apportionment of heavy metal in the surface soil of these areas has been analysed. Both the MSW open-burning sites probably contained invaluable e-waste and abandoned sites formerly involved in informal recycling activities are the new sources of soil-based environmental pollution in Guiyu. Although printed circuit board waste is thought to be the main source of heavy-metal emissions during e-waste processing, requirement is necessary to soundly manage the plastic separated from e-waste, which mostly contains heavy metals and other toxic substances.

  7. Assessment of toxic metals in waste personal computers

    International Nuclear Information System (INIS)

    Kolias, Konstantinos; Hahladakis, John N.; Gidarakos, Evangelos

    2014-01-01

    Highlights: • Waste personal computers were collected and dismantled in their main parts. • Motherboards, monitors and plastic housing were examined in their metal content. • Concentrations measured were compared to the RoHS Directive, 2002/95/EC. • Pb in motherboards and funnel glass of devices released <2006 was above the limit. • Waste personal computers need to be recycled and environmentally sound managed. - Abstract: Considering the enormous production of waste personal computers nowadays, it is obvious that the study of their composition is necessary in order to regulate their management and prevent any environmental contamination caused by their inappropriate disposal. This study aimed at determining the toxic metals content of motherboards (printed circuit boards), monitor glass and monitor plastic housing of two Cathode Ray Tube (CRT) monitors, three Liquid Crystal Display (LCD) monitors, one LCD touch screen monitor and six motherboards, all of which were discarded. In addition, concentrations of chromium (Cr), cadmium (Cd), lead (Pb) and mercury (Hg) were compared with the respective limits set by the RoHS 2002/95/EC Directive, that was recently renewed by the 2012/19/EU recast, in order to verify manufacturers’ compliance with the regulation. The research included disassembly, pulverization, digestion and chemical analyses of all the aforementioned devices. The toxic metals content of all samples was determined using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The results demonstrated that concentrations of Pb in motherboards and funnel glass of devices with release dates before 2006, that is when the RoHS Directive came into force, exceeded the permissible limit. In general, except from Pb, higher metal concentrations were detected in motherboards in comparison with plastic housing and glass samples. Finally, the results of this work were encouraging, since concentrations of metals referred in the RoHS Directive were found in

  8. Assessment of toxic metals in waste personal computers

    Energy Technology Data Exchange (ETDEWEB)

    Kolias, Konstantinos; Hahladakis, John N., E-mail: john_chach@yahoo.gr; Gidarakos, Evangelos, E-mail: gidarako@mred.tuc.gr

    2014-08-15

    Highlights: • Waste personal computers were collected and dismantled in their main parts. • Motherboards, monitors and plastic housing were examined in their metal content. • Concentrations measured were compared to the RoHS Directive, 2002/95/EC. • Pb in motherboards and funnel glass of devices released <2006 was above the limit. • Waste personal computers need to be recycled and environmentally sound managed. - Abstract: Considering the enormous production of waste personal computers nowadays, it is obvious that the study of their composition is necessary in order to regulate their management and prevent any environmental contamination caused by their inappropriate disposal. This study aimed at determining the toxic metals content of motherboards (printed circuit boards), monitor glass and monitor plastic housing of two Cathode Ray Tube (CRT) monitors, three Liquid Crystal Display (LCD) monitors, one LCD touch screen monitor and six motherboards, all of which were discarded. In addition, concentrations of chromium (Cr), cadmium (Cd), lead (Pb) and mercury (Hg) were compared with the respective limits set by the RoHS 2002/95/EC Directive, that was recently renewed by the 2012/19/EU recast, in order to verify manufacturers’ compliance with the regulation. The research included disassembly, pulverization, digestion and chemical analyses of all the aforementioned devices. The toxic metals content of all samples was determined using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The results demonstrated that concentrations of Pb in motherboards and funnel glass of devices with release dates before 2006, that is when the RoHS Directive came into force, exceeded the permissible limit. In general, except from Pb, higher metal concentrations were detected in motherboards in comparison with plastic housing and glass samples. Finally, the results of this work were encouraging, since concentrations of metals referred in the RoHS Directive were found in

  9. Management of metal-bearing industrial solid waste by stabilization/solidification process

    Energy Technology Data Exchange (ETDEWEB)

    Sunitha, C.; Palanivelu, K. [Anna University, Chennai (India). Centre for Environmental Studies

    2005-07-01

    Metal-bearing sludge from an electroplating industry was immobilised by the solidification stabilisation treatment method. Reduction of the leachability of metals from the waste was studied in different combinations of waste and additives - cement, lime and fly ash. The study revealed that the optimum proportion for cement: metal hydroxide sludge: fly ash as 1:2:2 is the best. The encapsulation efficiency calculated for the metals such as Cu, Cr, Ni, Pb, and Zn was above 92%. The unconfined compressive strength (UCS) for the developed block was found to be 11.5 kg/cm{sup 2} after curing. The toxicity characteristic leach test (TCLP) test reveals that the heavy metal content in the leachate was well below the maximum permissible limit of WHO drinking water standard. 10 refs., 6 tabs.

  10. Pitting corrosion as a mixed system: coupled deterministic-probabilistic simulation of pit growth

    Science.gov (United States)

    Ibrahim, Israr B. M.; Fonna, S.; Pidaparti, R.

    2018-05-01

    Stochastic behavior of pitting corrosion poses a unique challenge in its computational analysis. However, it also stems from electrochemical activity causing general corrosion. In this paper, a framework for corrosion pit growth simulation based on the coupling of the Cellular Automaton (CA) and Boundary Element Methods (BEM) is presented. The framework assumes that pitting corrosion is controlled by electrochemical activity inside the pit cavity. The BEM provides the prediction of electrochemical activity given the geometrical data and polarization curves, while the CA is used to simulate the evolution of pit shapes based on electrochemical activity provided by BEM. To demonstrate the methodology, a sample case of local corrosion cells formed in pitting corrosion with varied dimensions and polarization functions is considered. Results show certain shapes tend to grow in certain types of environments. Some pit shapes appear to pose a higher risk by being potentially significant stress raisers or potentially increasing the rate of corrosion under the surface. Furthermore, these pits are comparable to commonly observed pit shapes in general corrosion environments.

  11. 40 CFR Appendix B to Part 414 - Complexed Metal-Bearing Waste Streams

    Science.gov (United States)

    2010-07-01

    ... 414—Complexed Metal-Bearing Waste Streams Chromium Azo dye intermediates/Substituted diazonium salts + coupling compounds Vat dyes Acid dyes Azo dyes, metallized/Azo dye + metal acetate Acid dyes, Azo...

  12. Is Playing in the Pit Really the Pits?: Pain, Strength, Music Performance Anxiety, and Workplace Satisfaction in Professional Musicians in Stage, Pit, and Combined Stage/Pit Orchestras.

    Science.gov (United States)

    Kenny, Dianna T; Driscoll, Tim; Ackermann, Bronwen J

    2016-03-01

    Typically, Australian orchestral musicians perform on stage, in an orchestra pit, or in a combination of both workplaces. This study explored a range of physical and mental health indicators in musicians who played in these different orchestra types to ascertain whether orchestra environment was a risk factor affecting musician wellbeing. Participants comprised 380 full-time orchestral musicians from the eight major state orchestras in Australia comprised of two dedicated pit orchestras, three stage-only symphonic orchestras, and three mixed stage/pit orchestras. Participants completed a physical assessment and a range of self-report measures assessing performance-related musculoskeletal disorders (PRMD), physical characteristics including strength and perceived exertion, and psychological health, including music performance anxiety (MPA), workplace satisfaction, and bullying. Physical characteristics and performance-related musculoskeletal profiles were similar for most factors on the detailed survey completed by orchestra members. The exceptions were that pit musicians demonstrated greater shoulder and elbow strength, while mixed-workload orchestra musicians had greater flexibility Significantly more exertion was reported by pit musicians when rehearsing and performing. Stage/pit musicians reported less physical exertion when performing in the pit compared with performing on stage. Severity of MPA was significantly greater in pit musicians than mixed orchestra musicians. Pit musicians also reported more frequent bullying and lower job satisfaction compared with stage musicians. There were few differences in the objective physical measures between musicians in the different orchestra types. However, pit musicians appear more psychologically vulnerable and less satisfied with their work than musicians from the other two orchestra types. The physical and psychological characteristics of musicians who perform in different orchestra types have not been adequately

  13. Treatment and conditioning of metallic intermediate level waste

    International Nuclear Information System (INIS)

    Lidar, Per; Larsson, Arne; Huutoniemi, Tommi; Blank, Eva; Elfwing, Mattias

    2014-01-01

    In 2011 SKB started an R and D program for evaluating different disposal concepts for LL-LILW. The purpose was to develop alternative repository concepts and conditioning methods for LL-LILW and to evaluate and compare them from a range of parameters. The goal is to present a comparison between identified repository concepts by 2013. The material should be of such a quality that SKB can make decisions of which concepts that are to be further investigated in a safety analysis. As a part of the R and D program for the LL-LILW disposal facility, Studsvik was assigned to investigate whether melting of metallic LL-LILW is technically feasible and, if so, what the requirements are to build and operate such a facility. Specific concern was given to the following metallic components: - Core components and reactor internals from both boiling water reactors (BWRs) and pressurized water reactors (PWRs). - Reactor pressure vessels from PWRs. The paper presents a feasibility study of a melting facility for core components and reactor internals. An overview is given of how such a facility for treatment of intermediate level waste might be designed, constructed and operated and highlights both the possibilities and challenges. A cost estimate and a risk analysis are presented in order to make a conclusion of the technical feasibility of such a facility. Based on the Studsvik authors' experience in operating a low level waste melting facility, their conclusion is presented in the paper, considering cost of constructing and operating such a facility, in conjunction with the radio-logical risks associated with operation and the benefits to disposal and long term safety. Studsvik also investigated alternative techniques for embedding of metallic ILW components. Embedding of radioactive metallic ILW components protects the component from corrosion and leakage of radionuclides from repository to biosphere can thereby be both delayed and decreased. Conditioning by embedding has

  14. Corrosion behavior and pitting susceptibility of in-situ Ti-based metallic glass matrix composites in 3.5 wt.% NaCl solutions

    Science.gov (United States)

    Xu, K. K.; Lan, A. D.; Yang, H. J.; Han, P. D.; Qiao, J. W.

    2017-11-01

    The Ti62Zr12V13Cu4Be9, Ti58Zr16V10Cu4Be12, Ti46Zr20V12Cu5Be17, and Ti40Zr24V12Cu5Be19 metallic glass matrix composites (MGMCs) were prepared by copper mould casting. The corrosion resistance and the pitting susceptibility of Ti-based MGMCs were tested on their cross-sectional areas in 3.5 wt.% NaCl solutions by potentiodynamic polarization measurements. The composites with lower Ti contents (Ti40Zr24V12Cu5Be19 and Ti46Zr20V12Cu5Be17) exhibit a low resistance to the chloride induced pitting and local corrosion. The preferential dissolution of amorphous matrix is explained by the high chemical reactivity of beryllium element compared to that of stable dendrites and by the detected lower Ti and V contents. However, fairly good passivity was found in the composite with higher Ti contents (Ti62Zr12V13Cu4Be9). XPS measurements revealed that protective Ti-enriched oxide film was formed on the composite surface, additionally, lower content of beryllium element in amorphous matrix hinder the selective corrosion of amorphous matrix. The assessment of experimental observation leads to a proposed corrosion mechanism involving selective dissolution of amorphous matrix and chloride induced pitting process.

  15. Initial Evaluation of Processing Methods for an Epsilon Metal Waste Form

    International Nuclear Information System (INIS)

    Crum, Jarrod V.; Strachan, Denis M.; Zumhoff, Mac R.

    2012-01-01

    During irradiation of nuclear fuel in a reactor, the five metals, Mo, Pd, Rh, Ru, and Tc, migrate to the fuel grain boundaries and form small metal particles of an alloy known as epsilon metal ((var e psilon)-metal). When the fuel is dissolved in a reprocessing plant, these metal particles remain behind with a residue - the undissolved solids (UDS). Some of these same metals that comprise this alloy that have not formed the alloy are dissolved into the aqueous stream. These metals limit the waste loading for a borosilicate glass that is being developed for the reprocessing wastes. Epsilon metal is being developed as a waste form for the noble metals from a number of waste streams in the aqueous reprocessing of used nuclear fuel (UNF) - (1) the (var e psilon)-metal from the UDS, (2) soluble Tc (ion-exchanged), and (3) soluble noble metals (TRUEX raffinate). Separate immobilization of these metals has benefits other than allowing an increase in the glass waste loading. These materials are quite resistant to dissolution (corrosion) as evidenced by the fact that they survive the chemically aggressive conditions in the fuel dissolver. Remnants of (var e psilon)-metal particles have survived in the geologically natural reactors found in Gabon, Africa, indicating that they have sufficient durability to survive for ∼ 2.5 billion years in a reducing geologic environment. Additionally, the (var e psilon)-metal can be made without additives and incorporate sufficient foreign material (oxides) that are also present in the UDS. Although (var e psilon)-metal is found in fuel and Gabon as small particles (∼10 (micro)m in diameter) and has survived intact, an ideal waste form is one in which the surface area is minimized. Therefore, the main effort in developing (var e psilon)-metal as a waste form is to develop a process to consolidate the particles into a monolith. Individually, these metals have high melting points (2617 C for Mo to 1552 C for Pd) and the alloy is expected

  16. Melting of contaminated metallic waste

    International Nuclear Information System (INIS)

    Lee, Y.-S.; Cheng, S.-Y.; Kung, H.-T.; Lin, L.-F.

    2004-01-01

    Approximately 100 tons of contaminated metallic wastes were produced each year due to maintenance for each TPC's nuclear power reactor and it was roughly estimated that there will be 10,000 tons of metallic scraps resulted from decommissioning of each reactor in the future. One means of handling the contaminated metal is to melt it. Melting process owns not only volume reduction which saves the high cost of final disposal but also resource conservation and recycling benefits. Melting contaminated copper and aluminum scraps in the laboratory scale have been conducted at INER. A total of 546 kg copper condenser tubes with a specific activity of about 2.7 Bq/g was melted in a vacuum induction melting facility. Three types of products, ingot, slag and dust were derived from the melting process, with average activities of 0.10 Bq/g, 2.33 Bq/g and 84.3 Bq/g respectively. After the laboratory melting stage, a pilot plant with a 500 kg induction furnace is being designed to melt the increasingly produced contaminated metallic scraps from nuclear facilities and to investigate the behavior of different radionuclides during melting. (author)

  17. Study of the migration of toxic metals in steelmaking waste using radioactive tracing

    International Nuclear Information System (INIS)

    Andre, C.; Jauzein, M.; Charentus, T.; Margrita, R.; Dechelette, O.

    1991-01-01

    The danger presented by toxic metals contained in steelmaking wastes put into slag piles may be neutralized by suitably chosen alternation of these wastes when they are deposited. Presentation of a study method using radioactive tracing of the migration of toxic metal (cadmium, zinc, chromium) in steelmaking wastes (slag, blast furnace sludge). This non destructive method was used in columns in the laboratory, but may be used in on-site slag piles [fr

  18. Growth and metal bioconcentration by conspecific freshwater macroalgae cultured in industrial waste water.

    Science.gov (United States)

    Ellison, Michael B; de Nys, Rocky; Paul, Nicholas A; Roberts, David A

    2014-01-01

    The bioremediation of industrial waste water by macroalgae is a sustainable and renewable approach to the treatment of waste water produced by multiple industries. However, few studies have tested the bioremediation of complex multi-element waste streams from coal-fired power stations by live algae. This study compares the ability of three species of green freshwater macroalgae from the genus Oedogonium, isolated from different geographic regions, to grow in waste water for the bioremediation of metals. The experiments used Ash Dam water from Tarong power station in Queensland, which is contaminated by multiple metals (Al, Cd, Ni and Zn) and metalloids (As and Se) in excess of Australian water quality guidelines. All species had consistent growth rates in Ash Dam water, despite significant differences in their growth rates in "clean" water. A species isolated from the Ash Dam water itself was not better suited to the bioremediation of that waste water. While there were differences in the temporal pattern of the bioconcentration of metals by the three species, over the course of the experiment, all three species bioconcentrated the same elements preferentially and to a similar extent. All species bioconcentrated metals (Cu, Mn, Ni, Cd and Zn) more rapidly than metalloids (As, Mo and Se). Therefore, bioremediation in situ will be most rapid and complete for metals. Overall, all three species of freshwater macroalgae had the ability to grow in waste water and bioconcentrate elements, with a consistent affinity for the key metals that are regulated by Australian and international water quality guidelines. Together, these characteristics make Oedogonium a clear target for scaled bioremediation programs across a range of geographic regions.

  19. Growth and metal bioconcentration by conspecific freshwater macroalgae cultured in industrial waste water

    Directory of Open Access Journals (Sweden)

    Michael B. Ellison

    2014-05-01

    Full Text Available The bioremediation of industrial waste water by macroalgae is a sustainable and renewable approach to the treatment of waste water produced by multiple industries. However, few studies have tested the bioremediation of complex multi-element waste streams from coal-fired power stations by live algae. This study compares the ability of three species of green freshwater macroalgae from the genus Oedogonium, isolated from different geographic regions, to grow in waste water for the bioremediation of metals. The experiments used Ash Dam water from Tarong power station in Queensland, which is contaminated by multiple metals (Al, Cd, Ni and Zn and metalloids (As and Se in excess of Australian water quality guidelines. All species had consistent growth rates in Ash Dam water, despite significant differences in their growth rates in “clean” water. A species isolated from the Ash Dam water itself was not better suited to the bioremediation of that waste water. While there were differences in the temporal pattern of the bioconcentration of metals by the three species, over the course of the experiment, all three species bioconcentrated the same elements preferentially and to a similar extent. All species bioconcentrated metals (Cu, Mn, Ni, Cd and Zn more rapidly than metalloids (As, Mo and Se. Therefore, bioremediation in situ will be most rapid and complete for metals. Overall, all three species of freshwater macroalgae had the ability to grow in waste water and bioconcentrate elements, with a consistent affinity for the key metals that are regulated by Australian and international water quality guidelines. Together, these characteristics make Oedogonium a clear target for scaled bioremediation programs across a range of geographic regions.

  20. Selection of barrier metals for a waste package in tuff

    International Nuclear Information System (INIS)

    Russell, E.W.; McCright, R.D.; O'Neal, W.C.

    1983-10-01

    The Nevada Nuclear Waste Storage Investigations (NNWSI) project under the Civilian Radioactive Waste Management Program is planning a repository at Yucca Mountain at the Nevada Test Site for isolation of high-level nuclear waste. Lawrence Livermore National Laboratory is developing designs for an engineered barrier system containing several barriers such as the waste form, a canister and/or an overpack, packing, and near field host rock. In this paper we address the selection of metal containment barriers. 13 references, 4 tables

  1. Mechanism of pitting corrosion prevention by nitrite in carbon steel exposed to dilute salt solutions. 1998 annual progress report

    International Nuclear Information System (INIS)

    Zapp, P.E.; Zee, J. van.

    1998-01-01

    'The overall goal of this project is to develop a fundamental understanding of the role of nitrite in preventing the breakdown of protective oxide(s) on carbon steel and the onset of pitting. Pitting corrosion of carbon steel exposed to dilute alkaline salt solutions can be induced by nitrate, sulfate, and chloride ions and is prevented by sufficient concentration of nitrite. A significant example of this material/electrolyte system is the storage and processing of DOE''s high-level radioactive liquid waste in carbon steel tanks. Added nitrite in the waste has a considerable downstream impact on the immobilization of the waste in a stable glass form. Waste tank integrity and glass production efficiency may benefit from the fundamental understanding of nitrite''s role in preventing pitting. This report summarizes progress after approximately six months of effort in this three-year EMSP project. Initial experimental and theoretical work has focused on the electrochemical behavior of carbon steel in simplified non-radioactive solutions that simulate complex dilute radioactive waste solutions. These solutions contain corrosion-inducing species such as nitrate and chloride and the corrosion-inhibiting nitrite at moderately alkaline pHs. The electrochemical behavior of interest here is that of the open-circuit potential of the steel specimen at equilibrium in the experimental electrolyte and the measures of the steel''s passivity and passivity breakdown.'

  2. Corrosion of Metal Inclusions In Bulk Vitrification Waste Packages

    Energy Technology Data Exchange (ETDEWEB)

    Bacon, Diana H.; Pierce, Eric M.; Wellman, Dawn M.; Strachan, Denis M.; Josephson, Gary B.

    2006-07-31

    The primary purpose of the work reported here is to analyze the potential effect of the release of technetium (Tc) from metal inclusions in bulk vitrification waste packages once they are placed in the Integrated Disposal Facility (IDF). As part of the strategy for immobilizing waste from the underground tanks at Hanford, selected wastes will be immobilized using bulk vitrification. During analyses of the glass produced in engineering-scale tests, metal inclusions were found in the glass product. This report contains the results from experiments designed to quantify the corrosion rates of metal inclusions found in the glass product from AMEC Test ES-32B and simulations designed to compare the rate of Tc release from the metal inclusions to the release of Tc from glass produced with the bulk vitrification process. In the simulations, the Tc in the metal inclusions was assumed to be released congruently during metal corrosion as soluble TcO4-. The experimental results and modeling calculations show that the metal corrosion rate will, under all conceivable conditions at the IDF, be dominated by the presence of the passivating layer and corrosion products on the metal particles. As a result, the release of Tc from the metal particles at the surfaces of fractures in the glass releases at a rate similar to the Tc present as a soluble salt. The release of the remaining Tc in the metal is controlled by the dissolution of the glass matrix. To summarize, the release of 99Tc from the BV glass within precipitated Fe is directly proportional to the diameter of the Fe particles and to the amount of precipitated Fe. However, the main contribution to the Tc release from the iron particles is over the same time period as the release of the soluble Tc salt. For the base case used in this study (0.48 mass% of 0.5 mm diameter metal particles homogeneously distributed in the BV glass), the release of 99Tc from the metal is approximately the same as the release from 0.3 mass% soluble Tc

  3. Immobilization of metal wastes by reaction with H2S in anoxic basins: concept and elaboration.

    Science.gov (United States)

    Schuiling, R D

    2013-10-01

    Metal wastes are produced in large quantities by a number of industries. Their disposal in isolated waste deposits is certain to cause many subsequent problems, because every material will sooner or later return to the geochemical cycle. The sealing of disposal sites usually starts to leak, often within a short time after the disposal site has been filled. The contained heavy metals are leached from the waste deposit and will contaminate the soil and the groundwater. It is evident that storage as metal sulfides in a permanently anoxic environment is the only safe way to handle metal wastes. The world's largest anoxic basin, the Black Sea, can serve as a georeactor. The metal wastes are sustainably transformed into harmless and immobile solids. These are incorporated in the lifeless bottom muds, where they are stored for millions of years.

  4. Particle Size (Sieving) and Enthalpy (Acid Calorimetry) Analysis of Single-Pull K East Basin Floor and Pit Sludges

    International Nuclear Information System (INIS)

    Bredt, P.R.; Delegard, C.H.; Schmidt, A.J.; Silvers, K.L.; Thornton, B.M.; Gano, S.

    2000-01-01

    This report presents the results of particle size analyses and calorimetry testing performed on selected single-pull sludge samples collected from the Hanford K East Basin between December 1998 and June 1999. The samples were collected as isolated cores predominantly from areas that had not been previously sampled (e.g., North Loadout Pit, Dummy Elevator Pit, Tech View Pit), or from areas in which the sludge composition had been altered since the last sampling (e.g., Weasel Pit). Particle size analyses were performed by washing wet sludge samples through a series of four sieves with openings of 250, 500, 1410, and 4000 microm. The loaded sieves were weighed before and after drying to obtain wet and dry particle size distributions. Knowledge of the particle size distribution is needed to design and predict the performance of the systems that will be used to retrieve, transport, and recover sludge. Also, sieving provides an opportunity to observe the components in the sludge. For example, during sieving of the sludge sample from the North Loadout Pit, significant quantities of organic ion exchange beads were observed. The uranium metal content and the particle size of the uranium metal in the K Basin sludge will largely determine the chemical reactivity of the sludge. In turn, the designs for the sludge handling and storage systems must be compatible with the reactivity of the sludge. Therefore, acid calorimetry was performed to estimate the uranium metal content of the sludge. For this testing, sludge samples were dissolved in nitric acid within a calibrated adiabatic calorimeter. The resulting dissolution enthalpy data were then used to discriminate between metallic uranium (minus3750 J/g in nitric acid) and uranium oxide (minus394 J/g in nitric acid). Results from this testing showed that the single-pull sludge samples contained little or no uranium metal

  5. Mechanism of Pitting Corrosion Prevention by Nitrite in Carbon Steel Exposed to Dilute Salt Solutions

    International Nuclear Information System (INIS)

    Zapp, Philip E.; Zee, John W. van

    2002-01-01

    The research has developed a broad fundamental understanding of the inhibition action of nitrite ions in preventing nitrate pitting corrosion of carbon steel tanks containing high-level radioactive waste. This fundamental understanding can be applied to specific situations during waste removal for permanent disposition and waste tank closure to ensure that the tanks are maintained safely. The results of the research provide the insight necessary to develop solutions that prevent further degradation

  6. Solidification of metal chloride waste from pyrochemical process via dechlorination-chlorination reaction system

    Energy Technology Data Exchange (ETDEWEB)

    Park, H.S.; Cho, I.H.; Lee, K.R.; Choi, J.H.; Eun, H.C.; Kim, I.T.; Park, G.I. [Korea Atomic Energy Research Inst., Deajeon (Korea, Republic of)

    2014-07-01

    The metal chloride wastes generated from the pyro-chemical process to recover uranium and TRUs has been considered as a problematic waste due to the high volatility and low compatibility with conventional silicate glass. Our research group has suggested the dechlorination approach for the solidification of this kind of waste by using a synthetic composite, SAP (SiO{sub 2}-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}). During the dechlorination, metal elements are chemically interacted with the inorganic composite, SAP, while chlorine is vaporized as gaseous chlorine. Metal elements in the salt were immobilized into phosphate and silicate glass which are uniformly distributed in tens of nm scale. During the dechlorination, gaseous chlorine is captured by Li{sub 2}O-Li{sub 2}O{sub 2} composite that can be converted into metal chloride (LiCl). About 98wt% of oxide composite was converted into LiCl that can be used as an electrolyte in the electrochemical process. The method suggested in this study can provide a chance to minimize the waste volume for the final disposal of salt wastes from a pyro-chemical process. (author)

  7. Remaining Sites Verification Package for the 126-B-3, 184-B Coal Pit Dumping Area. Attachment to Waste Site Reclassification Form 2005-028

    International Nuclear Information System (INIS)

    Dittmer, L.M.

    2006-01-01

    The 126-B-3 waste site is the former coal storage pit for the 184-B Powerhouse. During demolition operations in the 1970s, the site was used for disposal of demolition debris from 100-B/C Area facilities. The site has been remediated by removing debris and contaminated soils. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River

  8. CHerenkov detectors In mine PitS (CHIPS) Letter of Intent to FNAL

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P. [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Austin, J. [Univ. of Minnesota, Duluth, MN (United States); Cao, S. V. [Univ. of Texas, Austin, TX (United States); Coelho, J. A. B. [Tufts Univ., Medford, MA (United States); Davies, G. S. [Iowa State Univ., Ames, IA (United States); Evans, J. J. [Univ. of Manchester (United Kingdom); Guzowski, P. [Univ. of Manchester (United Kingdom); Habig, A. [Univ. of Minnesota, Duluth, MN (United States); Holin, A. [Univ. College London, London (United Kingdom); Huang, J. [Univ. of Texas, Austin, TX (United States); Johnson, R. [Univ. of Cincinnati, OH (United States); St. John, J. [Univ. of Cincinnati, OH (United States); Kreymer, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Kordosky, M. [College of William and Mary, Williamsburg, VA (United States); Lang, K. [Univ. of Texas, Austin, TX (United States); Marshak, M. L. [Univ. of Minnesota, Minneapolis, MN (United States); Mehdiyev, R. [Univ. of Texas, Austin, TX (United States); Meier, J. [Univ. of Minnesota, Minneapolis, MN (United States); Miller, W. [Univ. of Minnesota, Minneapolis, MN (United States); Naples, D. [Univ. of Pittsburgh, PA (United States); Nelson, J. K. [College of William and Mary, Williamsburg, VA (United States); Nichol, R. J. [Univ. College London, London (United Kingdom); Patterson, R. B. [California Inst. of Technology (CalTech), Pasadena, CA (United States); Paolone, V. [Univ. of Pittsburgh, PA (United States); Pawloski, G. [Univ. of Minnesota, Minneapolis, MN (United States); Perch, A. [Univ. College London, London (United Kingdom); Pfutzner, M. [Univ. College London, London (United Kingdom); Proga, M. [Univ. of Texas, Austin, TX (United States); Qian, X. [Brookhaven National Lab. (BNL), Upton, NY (United States); Radovic, A. [Univ. College London, London (United Kingdom); Sanchez, M. C. [Iowa State Univ., Ames, IA (United States); Schreiner, S. [Univ. of Minnesota, Minneapolis, MN (United States); Soldner-Rembold, S. [Univ. of Manchester (United Kingdom); Sousa, A. [Univ. of Cincinnati, OH (United States); Thomas, J. [Univ. College London, London (United Kingdom); Vahle, P. [College of William and Mary, Williamsburg, VA (United States); Wendt, C. [Univ. of Wisconsin, Madison, WI (United States); Whitehead, L. H. [Univ. College London, London (United Kingdom); Wojcicki, S. [Stanford Univ., CA (United States)

    2013-12-30

    This Letter of Intent outlines a proposal to build a large, yet cost-effective, 100 kton fiducial mass water Cherenkov detector that will initially run in the NuMI beam line. The CHIPS detector (CHerenkov detector In Mine PitS) will be deployed in a flooded mine pit, removing the necessity and expense of a substantial external structure capable of supporting a large detector mass. There are a number of mine pits in northern Minnesota along the NuMI beam that could be used to deploy such a detector. In particular, the Wentworth Pit 2W is at the ideal off-axis angle to contribute to the measurement of the CP violating phase. The detector is designed so that it can be moved to a mine pit in the LBNE beam line once that becomes operational.

  9. The study on the overseas recycling technology of the radioactive metallic wastes

    International Nuclear Information System (INIS)

    Kim, H. R.; Jung, Y. S.; Sin, J. I.

    2002-01-01

    It was understood that regulation criteria for material release varied with countries and that international standards were not setup. But, most advanced countries are continuously studying on the recycling of metallic wastes for the purpose of the reuse of resources and disposal cost reduction. Practically, the advanced countries make a lot of cost profits compared with disposal as their metallic wastes are recycled and reused through technology like melting. In our case, the recycle criteria for radioactive waste containing radioactive nuclide with long half-life such as Cs-137(half-life: 30y) and Co-60(half-life: 5.26y) including others, which are generated from the nuclear fission or dismantling of nuclear facilities, are not yet established. Therefore, it is required that the recommendation and legalization of the regulatory criteria be carried out for the recycle and reuse of metallic wastes to be generated from the dismantling of domestic nuclear facilities in the future

  10. Stochastic modeling of pitting corrosion: A new model for initiation and growth of multiple corrosion pits

    International Nuclear Information System (INIS)

    Valor, A.; Caleyo, F.; Alfonso, L.; Rivas, D.; Hallen, J.M.

    2007-01-01

    In this work, a new stochastic model capable of simulating pitting corrosion is developed and validated. Pitting corrosion is modeled as the combination of two stochastic processes: pit initiation and pit growth. Pit generation is modeled as a nonhomogeneous Poisson process, in which induction time for pit initiation is simulated as the realization of a Weibull process. In this way, the exponential and Weibull distributions can be considered as the possible distributions for pit initiation time. Pit growth is simulated using a nonhomogeneous Markov process. Extreme value statistics is used to find the distribution of maximum pit depths resulting from the combination of the initiation and growth processes for multiple pits. The proposed model is validated using several published experiments on pitting corrosion. It is capable of reproducing the experimental observations with higher quality than the stochastic models available in the literature for pitting corrosion

  11. Stochastic modeling of pitting corrosion: A new model for initiation and growth of multiple corrosion pits

    Energy Technology Data Exchange (ETDEWEB)

    Valor, A. [Facultad de Fisica, Universidad de La Habana, San Lazaro y L, Vedado, 10400 Havana (Cuba); Caleyo, F. [Departamento de Ingenieria, Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico)]. E-mail: fcaleyo@gmail.com; Alfonso, L. [Departamento de Ingenieria, Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico); Rivas, D. [Departamento de Ingenieria, Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico); Hallen, J.M. [Departamento de Ingenieria, Metalurgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Mexico DF 07738 (Mexico)

    2007-02-15

    In this work, a new stochastic model capable of simulating pitting corrosion is developed and validated. Pitting corrosion is modeled as the combination of two stochastic processes: pit initiation and pit growth. Pit generation is modeled as a nonhomogeneous Poisson process, in which induction time for pit initiation is simulated as the realization of a Weibull process. In this way, the exponential and Weibull distributions can be considered as the possible distributions for pit initiation time. Pit growth is simulated using a nonhomogeneous Markov process. Extreme value statistics is used to find the distribution of maximum pit depths resulting from the combination of the initiation and growth processes for multiple pits. The proposed model is validated using several published experiments on pitting corrosion. It is capable of reproducing the experimental observations with higher quality than the stochastic models available in the literature for pitting corrosion.

  12. Children with health impairments by heavy metals in an e-waste recycling area.

    Science.gov (United States)

    Zeng, Xiang; Xu, Xijin; Boezen, H Marike; Huo, Xia

    2016-04-01

    E-waste recycling has become a global environmental health issue. Pernicious chemicals escape into the environment due to informal and nonstandard e-waste recycling activities involving manual dismantling, open burning to recover heavy metals and open dumping of residual fractions. Heavy metals derived from electronic waste (e-waste), such as, lead (Pb), cadmium (Cd), chromium (Cr), manganese (Mn), nickel (Ni), mercury (Hg), arsenic (As), copper (Cu), zinc (Zn), aluminum (Al) and cobalt (Co), differ in their chemical composition, reaction properties, distribution, metabolism, excretion and biological transmission. Our previous studies showed that heavy metal exposure have adverse effects on children's health including lower birth weight, lower anogenital distance, lower Apgar scores, lower current weight, lower lung function, lower hepatitis B surface antibody levels, higher prevalence of attention-deficit/hyperactivity disorder, and higher DNA and chromosome damage. Heavy metals influence a number of diverse systems and organs, resulting in both acute and chronic effects on children's health, ranging from minor upper respiratory irritation to chronic respiratory, cardiovascular, nervous, urinary and reproductive disease, as well as aggravation of pre-existing symptoms and disease. These effects of heavy metals on children's health are briefly discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Pitting corrosion susceptibility study of zirconium alloys in the presence of the chloride ions

    International Nuclear Information System (INIS)

    Radulescu, M.; Pirvan, I.; Velciu, L.

    1997-01-01

    Pitting corrosion mechanism is specific to metal/aggressive environment systems. The influence of both components of the process was thoroughly investigated. After reviewing the principal steps of the pitting corrosion and of the electrochemical reactions associated, there were presented the physico-chemical methods used for the determination of the corrosion pitting parameters completed with the metallographic techniques of investigation of the attacked surfaces. Reported are the results of determinations of the pit initiation (E np ) and pit passivation (E pp ) potentials in the systems Zy-4 (Zr)/ Cl - provided from the following solutions: HCl, FeCl 3 , NaCl and LiCl. In the case of the last two solutions, the measurements were carried out also in the range of alkaline pH values. It was also determined the dependence of E np and E pp potential on the Cl - ions concentration in NaCl and HCl solutions, and also the reaction order 'n' in presence of several chloride concentration. Finally, on the basis of the experimental data, we established the kinetic characteristics specific to different steps of pitting. (authors)

  14. Lauryl Amine as heavy metal collector of boiler ash from pulp and paper mill waste

    Science.gov (United States)

    Sembiring, M. P.; Kaban, J.; Bangun, N.; Saputra, E.

    2018-04-01

    Theincreasing of demand of pulp and paper products, will following with the growing the pulp and paper industryand generate significant mill waste. The total waste reached 1/3 of the amount raw materials used and ash boiler is the waste with the largest percentage of 52%. For that it takes effort to manage the existing waste. The boiler ash contained the chemical elements, it can be utilized such as fertilizer, because it also contains transition metals in form of heavy metal such as Cadmium (Cd), Cobalt (Co), Chrome (Cr), Cupprum (Cu), Ferrum (Fe), Nickel (Ni), and Zinc (Zn), the use of boiler ash must follow the threshold specified by the Government. Several studies have been undertaken to reduce and extract heavy metals from ash and sand of the boiler by using carbon dioxide as its ligand. Eelectrochemical method was used to remove and recovery of heavy metals from the incenerator. This study focused on removal of heavy metals using Lauryl Amine as collector and three solvents namely Dichloromethane, Ethanol and n-Hexane. The treatmentswas able to extract the heavy metal and generally reduce the heavy metal content of ash boiler pulp and paper mill waste. The combination treatment used toreduce the heavy metal content of 5 gram Lauryl Amine collector in Dichloromethane solvent for 4 hours process time.

  15. An assessment on the recycling opportunities of wastes emanating from scrap metal processing in Mauritius

    Energy Technology Data Exchange (ETDEWEB)

    Mauthoor, Sumayya, E-mail: sumayya.mauthoor@umail.uom.ac.mu [Department of Chemical and Environmental Engineering, University of Mauritius, Réduit (Mauritius); Mohee, Romeela [Professor of Chemical and Environmental Engineering, National Research Chair in Solid Waste Management, Mauritius Research Council (Mauritius); Kowlesser, Prakash [Solid Waste/Beach Management Unit, Ministry of Local Government and Outer Islands (Mauritius)

    2014-10-15

    Highlights: • Scrap metal processing wastes. • Areas of applications for slag, electric arc furnace dust, mill scale and wastewater sludge. • Waste generation factor of 349.3 kg per ton of steel produced. • Waste management model. - Abstract: This paper presents an assessment on the wastes namely slag, dust, mill scale and sludge resulting from scrap metal processing. The aim of this study is to demonstrate that there are various ways via which scrap metal processing wastes can be reused or recycled in other applications instead of simply diverting them to the landfill. These wastes are briefly described and an overview on the different areas of applications is presented. Based on the results obtained, the waste generation factor developed was 349.3 kg per ton of steel produced and it was reported that slag represents 72% of the total wastes emanating from the iron and steel industry in Mauritius. Finally the suitability of the different treatment and valorisation options in the context of Mauritius is examined.

  16. Leaching characteristics of the metal waste form from the electrometallurgical treatment process: Product consistency testing

    International Nuclear Information System (INIS)

    Johnson, S. G.; Keiser, D. D.; Frank, S. M.; DiSanto, T.; Noy, M.

    1999-01-01

    Argonne National Laboratory is developing an electrometallurgical treatment for spent fuel from the experimental breeder reactor II. A product of this treatment process is a metal waste form that incorporates the stainless steel cladding hulls, zirconium from the fuel and the fission products that are noble to the process, i.e., Tc, Ru, Nb, Pd, Rh, Ag. The nominal composition of this waste form is stainless steel/15 wt% zirconium/1--4 wt% noble metal fission products/1--2 wt % U. Leaching results are presented from several tests and sample types: (1) 2 week monolithic immersion tests on actual metal waste forms produced from irradiated cladding hulls, (2) long term (>2 years) pulsed flow tests on samples containing technetium and uranium and (3) crushed sample immersion tests on cold simulated metal waste form samples. The test results will be compared and their relevance for waste form product consistency testing discussed

  17. Metal waste forms from the electrometallurgical treatment of spent nuclear fuel

    International Nuclear Information System (INIS)

    Abraham, D.P.; McDeavitt, S.M.; Park, J.

    1996-01-01

    Stainless steel-zirconium alloys are being developed for the disposal of radioactive metal isotopes isolated using an electrometallurgical treatment technique to treat spent nuclear fuel. The nominal waste forms are stainless steel-15 wt% zirconium alloy and zirconium-8 wt% stainless steel alloy. These alloys are generated in yttria crucibles by melting the starting materials at 1,600 C under an argon atmosphere. This paper discusses the microstructures, corrosion and mechanical test results, and thermophysical properties of the metal waste form alloys

  18. Novel recycle technology for recovering rare metals (Ga, In) from waste light-emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Zhan, Lu; Xia, Fafa; Ye, Qiuyu; Xiang, Xishu; Xie, Bing, E-mail: bxie@des.ecnu.edu.cn

    2015-12-15

    Highlights: • Rare metals (Ga, In) are separated and recycled from waste light-emitting diodes. • Pyrolysis, physical disaggregation and vacuum metallurgy separation are proposed. • There is no hazardous materials produced in this process. - Abstract: This work develops a novel process of recycling rare metals (Ga, In) from waste light-emitting diodes using the combination of pyrolysis, physical disaggregation methods and vacuum metallurgy separation. Firstly, the pure chips containing InGaN/GaN are adopted to study the vacuum separation behavior of rare metals, which aims to provide the theoretical foundation for recycling gallium and indium from waste light-emitting diodes. In order to extract the rare-metal-rich particles from waste light-emitting diodes, pyrolysis and physical disaggregation methods (crushing, screening, grinding and secondly screening) are studied respectively, and the operating parameters are optimized. With low boiling points and high saturation vapor pressures under vacuum, gallium and indium are separated from rare-metal-rich particles by the process of evaporation and condensation. By reference to the separating parameters of pure chips, gallium and indium in waste light-emitting diodes are recycled with the recovery efficiencies of 93.48% and 95.67% under the conditions as follows: heating temperature of 1373 K, vacuum pressure of 0.01–0.1 Pa, and holding time of 60 min. There are no secondary hazardous materials generated in the whole processes. This work provides an efficient and environmentally friendly process for recycling rare metals from waste light-emitting diodes.

  19. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J.C.; Van Konynenburg, R.A.; McCright, R.D. (Lawrence Livermore National Lab., CA (USA)); Bullen, D.B. (Science and Engineering Associates, Inc., Pleasanton, CA (USA))

    1988-04-01

    Three iron- to nickel-based austenitic alloys (Types 304L and 316L stainless steels and Alloy 825) are being considered as candidate materials for the fabrication of high-level radioactive-waste containers. Waste will include fuel assemblies from reactors as well as high-level waste in borosilicate glass forms, and will be sent to the prospective repository at Yucca Mountain, Nevada. The decay of radionuclides in the repository will result in the generation of substantial heat and in fluences of gamma radiation. Container materials may undergo any of several modes of degradation in this environment, including atmospheric oxidation; uniform aqueous phase corrosion; pitting; crevice corrosion; sensitization and intergranular stress corrosion cracking (IGSCC); and transgranular stress corrosion cracking (TGSCC). This report is an analysis of data relevant to the pitting, crevice corrosion, and stress corrosion cracking (SCC) of the three austenitic candidate alloys. The candidates are compared in terms of their susceptibilities to these forms of corrosion. Although all three candidates have demonstrated pitting and crevice corrosion in chloride-containing environments, Alloy 825 has the greatest resistance to these types of localized corrosion (LC); such resistance is important because pits can penetrate the metal and serve as crack initiation sites. Both Types 304L and 316L stainless steels are susceptible to SCC in acidic chloride media. In contrast, SCC has not been documented in Alloy 825 under comparable conditions. Gamma radiation has been found to enhance SCC in Types 304 and 304L stainless steels, but it has no detectable effect on the resistance of Alloy 825 to SCC. Furthermore, while the effects of microbiologically induced corrosion have been observed for 300-series stainless steels, nickel-based alloys such as Alloy 825 seem to be immune to such problems. 211 refs., 49 figs., 10 tabs.

  20. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    International Nuclear Information System (INIS)

    Farmer, J.C.; Van Konynenburg, R.A.; McCright, R.D.; Bullen, D.B.

    1988-04-01

    Three iron- to nickel-based austenitic alloys (Types 304L and 316L stainless steels and Alloy 825) are being considered as candidate materials for the fabrication of high-level radioactive-waste containers. Waste will include fuel assemblies from reactors as well as high-level waste in borosilicate glass forms, and will be sent to the prospective repository at Yucca Mountain, Nevada. The decay of radionuclides in the repository will result in the generation of substantial heat and in fluences of gamma radiation. Container materials may undergo any of several modes of degradation in this environment, including atmospheric oxidation; uniform aqueous phase corrosion; pitting; crevice corrosion; sensitization and intergranular stress corrosion cracking (IGSCC); and transgranular stress corrosion cracking (TGSCC). This report is an analysis of data relevant to the pitting, crevice corrosion, and stress corrosion cracking (SCC) of the three austenitic candidate alloys. The candidates are compared in terms of their susceptibilities to these forms of corrosion. Although all three candidates have demonstrated pitting and crevice corrosion in chloride-containing environments, Alloy 825 has the greatest resistance to these types of localized corrosion (LC); such resistance is important because pits can penetrate the metal and serve as crack initiation sites. Both Types 304L and 316L stainless steels are susceptible to SCC in acidic chloride media. In contrast, SCC has not been documented in Alloy 825 under comparable conditions. Gamma radiation has been found to enhance SCC in Types 304 and 304L stainless steels, but it has no detectable effect on the resistance of Alloy 825 to SCC. Furthermore, while the effects of microbiologically induced corrosion have been observed for 300-series stainless steels, nickel-based alloys such as Alloy 825 seem to be immune to such problems. 211 refs., 49 figs., 10 tabs

  1. Separating and recycling metals from mixed metallic particles of crushed electronic wastes by vacuum metallurgy.

    Science.gov (United States)

    Zhan, Lu; Xu, Zhenming

    2009-09-15

    During the treatment of electronic wastes, a crushing process is usually used to strip metals from various base plates. Several methods have been applied to separate metals from nonmetals. However, mixed metallic particles obtained from these processes are still a mixture of various metals, including some toxic heavy metals such as lead and cadmium. With emphasis on recovering copper and other precious metals, there have hitherto been no satisfactory methods to recover these toxic metals. In this paper, the criterion of separating metals from mixed metallic particles by vacuum metallurgy is built. The results show that the metals with high vapor pressure have been almost recovered completely, leading to a considerable reduction of environmental pollution. In addition, the purity of copper in mixed particles has been improved from about 80 wt % to over 98 wt %.

  2. Implication of heavy metals distribution for a municipal solid waste management system - a case study in Shanghai

    International Nuclear Information System (INIS)

    Zhang Hua; He Pinjing; Shao Liming

    2008-01-01

    Heavy metal contamination in municipal solid waste (MSW) is of increasing concern. The occurrence and distribution of heavy metals in MSW and their implications for the integrated MSW management system in mega-cities have been investigated by means of material flow analysis based on a case study of Shanghai in China. A good statistical basis was provided through a one-year monitoring program on the mass and metals composition of the waste from three MSW treatment facilities. The results showed that the main heavy metals in the MSW were Zn, Cr, Cu, and Pb (on average > 100 mg kg -1 ), followed by Ni, Cd, and Hg. The MSW contained higher levels of Cu and Ni in metals, Cr and Pb in plastics, and Pb and Zn in the inorganic fractions. Regardless of the sources, the statistically similar heavy metal contents in the organic fractions indicated that effective blending and diffusion of heavy metals had taken place throughout the MSW collection, transfer, transportation, and storage, leading to cross-contamination of the waste fractions. PU (composed of putrescible waste and miscellaneous indistinguishable particles) contributed the majority of the heavy metals to the MSW, followed by plastics, as a result of the predominance in the overall composition of PU and plastics rather than from differences in their heavy metal contents. Therefore, manual or mechanical separation of some significantly heavy metal-rich fractions alone is not sufficient to reduce the heavy metal contents in the MSW. Source separation of organic waste and the diversion of tailored inorganic waste such as hazardous components, construction and demolition waste, etc., are proposed to control the heavy metal contamination in MSW. For the mixed MSW management system, physicochemical fractionation to exclude particles containing high levels of heavy metals can be conducted

  3. Implication of heavy metals distribution for a municipal solid waste management system - a case study in Shanghai

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Hua [State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China); He Pinjing [State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China)], E-mail: solidwaste@mail.tongji.edu.cn; Shao Liming [State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China)

    2008-09-01

    Heavy metal contamination in municipal solid waste (MSW) is of increasing concern. The occurrence and distribution of heavy metals in MSW and their implications for the integrated MSW management system in mega-cities have been investigated by means of material flow analysis based on a case study of Shanghai in China. A good statistical basis was provided through a one-year monitoring program on the mass and metals composition of the waste from three MSW treatment facilities. The results showed that the main heavy metals in the MSW were Zn, Cr, Cu, and Pb (on average > 100 mg kg{sup -1}), followed by Ni, Cd, and Hg. The MSW contained higher levels of Cu and Ni in metals, Cr and Pb in plastics, and Pb and Zn in the inorganic fractions. Regardless of the sources, the statistically similar heavy metal contents in the organic fractions indicated that effective blending and diffusion of heavy metals had taken place throughout the MSW collection, transfer, transportation, and storage, leading to cross-contamination of the waste fractions. PU (composed of putrescible waste and miscellaneous indistinguishable particles) contributed the majority of the heavy metals to the MSW, followed by plastics, as a result of the predominance in the overall composition of PU and plastics rather than from differences in their heavy metal contents. Therefore, manual or mechanical separation of some significantly heavy metal-rich fractions alone is not sufficient to reduce the heavy metal contents in the MSW. Source separation of organic waste and the diversion of tailored inorganic waste such as hazardous components, construction and demolition waste, etc., are proposed to control the heavy metal contamination in MSW. For the mixed MSW management system, physicochemical fractionation to exclude particles containing high levels of heavy metals can be conducted.

  4. Current Program for the management of U.S. Department of Energy transuranic waste

    International Nuclear Information System (INIS)

    Harms, T.

    1994-01-01

    The existing inventory of TRU waste can be divided into tow distinct components: (1) retrievably stored TRU waste and (2) buried TRU waste. The distinction between open-quotes storedclose quotes and open-quotes buriedclose quotes TRU waste was established in 1970 when the Atomic Energy Commission (AEC) determined that TRU-contaminated waste, when disposed, should have more effective isolation from the environment than the confinement provided by burial in pits and trenches covered with soil. Buried TRU (and contaminated soils surrounding buried TRU) are the results of disposal operations carried out at DOE sites prior to the 1970 decision. The inventory of buried TRU is 190,600 m 3 . This waste is the responsibility of the Office of Environmental Restoration (EM-40). All TRU waste generated since 1970 has been placed in storage at six DOE sites. This storage was designed with a lifetime expected to be 20 years. The waste is stored in retrievable form for eventual shipment and disposal at a geologic repository. Currently, TRU waste is contained in a variety of packaging, including metal drums and wooden and metal boxes, and stored in earth-mounded berms, concrete culverts, or other facilities. At the end of 1991, there were approximately 64,000 m 3 of retrievably stored TRU waste. With the WIPP facility not becoming operational until the year 2000 or later, the DOE must effectively manage this waste in other manners. The issues regarding the management of TRU wastes is described

  5. Direct conversion of radioactive and chemical waste containing metals, ceramics, amorphous solids, and organics to glass

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

    1994-01-01

    The Glass Material Oxidation and Dissolution System (CMODS) is a new process for direct conversion of radioactive, mixed, and chemical wastes to glass. The wastes can be in the chemical forms of metals, ceramics, amorphous solids, and organics. GMODS destroys organics and it incorporates heavy metals and radionuclides into a glass. Processable wastes may include miscellaneous spent fuels (SF), SF hulls and hardware, plutonium wastes in different forms, high-efficiency particulate air (HEPA) filters, ion-exchange resins, failed equipment, and laboratory wastes. Thermodynamic calculations indicate theoretical feasibility. Small-scale laboratory experiments (< 100 g per test) have demonstrated chemical laboratory feasibility for several metals. Additional work is needed to demonstrate engineering feasibility

  6. Plant succession patterns on residual open-pit gravel mines deposits Bogota

    Directory of Open Access Journals (Sweden)

    Ricardo A. Mora Goyes

    1999-07-01

    Full Text Available Based on both: the study of composition and structure of plant communities and the analysis of the physico-chemical characteristics of mining wastes, the initial patterns of primary succession were determined. These patterns were present in three deposits of waste material abandoned during 18, 36 and 120 months respectively. Sue materials were originated in open-pit gravel mines located to the south of Bogota (Colombia. This study pretends to contribute to the knowledge of the meehanlsms of natural restauration of tropical ecosystems subjected to man-borne degradation.

  7. The Great Bear Flare Pit Project : review of work to date

    International Nuclear Information System (INIS)

    Ridal, J.; Lean, D.; Findlay, S.C.

    1998-01-01

    Published information regarding potential toxic agents associated with flare emissions and a study to determine the risk posed to Treaty 8 First Nations (T8FN) peoples and wildlife was reviewed as part of the Great Bear Flare Pit Project (GBFPP). The project is concerned with the study of water and soil contamination in the immediate vicinity of flare pits in the Del Rio, Doig basin, Blueberry River, and Halfway River regions of T8FN lands in Alberta. The GBFPP has established good baseline data on metal contamination, and other contaminants such as benzene, toluene, ethylbenzene, xylenes (BTEX) and polycyclic aromatic hydrocarbons (PAHs) in the immediate vicinity of selected flare pits. Based on a critical assessment of reports published to date a series of prioritized recommendations for further research are made. 18 refs., 2 tabs

  8. Lime treatment of liquid waste containing heavy metals, radionuclides and organics

    International Nuclear Information System (INIS)

    DuPont, A.

    1990-01-01

    This paper reports on lime treatment of liquid waste containing heavy metals, radio nuclides and organics. Lime is wellknown for its use in softening drinking water the treatment of municipal wastewaters. It is becoming important in the treatment of industrial wastewater and liquid inorganic hazardous waste; however, there are many questions regarding the use of lime for the treatment of liquid hazardous waste

  9. Water quality in gravel pits in the Bratislava area

    International Nuclear Information System (INIS)

    Flakova, R.; Rohacikova, A.; Zenisova, Z.

    1999-01-01

    The gravel pits around Bratislava have an esthetic, urban and recreational function. Open water table areas are in a direct contact with the air and acquire some characteristics of the surface water. The quality of open water table is much more susceptible to pollution than that of groundwater. Wet and dry deposition, water inflow from the surrounding surface, unmanageable sewerage effluents, solid and liquid wastes, but also the water birds contribute to the pollution. The Department of Hydrogeology has monitored the water quality in six gravel pits (Cunovo, Drazdiak, Strkovec, Pasienky, Zlate Piesky, Vajnory) since 1976 with an an interruption between 1988 - 1993. Two sampling per year have been made since 1994 and after 1998 the analyses have been supplemented by Na, K, Fe, Mn, by oxygen regime parameters, by trace elements (As, Ag, Cd, Co, Cu, Cr, Hg, Ni, Pb, V, Zn) and by organic pollutants. As regards the oxygen regime, the water quality pits is very good. The anthropogenic influence is expressed mainly by the increased contents of sulfates and chlorides. Most problematic trace elements are the mercury and vanadium (Drazdiak, Zlate Piesky and Vajnory). (authors)

  10. Leaching of gold, silver and accompanying metals from circuit boards (PCBs waste

    Directory of Open Access Journals (Sweden)

    Jana Ficeriová

    2011-12-01

    Full Text Available Au-Ag noble metal wastes represent a wide range of waste types and forms, with various accompanying metallic elements.The presented leaching strategy for Au-Ag contained in circuit boards (PCBs aims at gaining gold and silver in the metallic form.Application of the proposed ammonium thiosulphate leaching process for the treatment of the above mentioned Au-Ag containing wastesrepresents a practical, economic and at the same time an ecological solution. The ammonium thiosulphate based leaching of gold and silverfrom PCBs waste, using crushing as a pretreatment, was investigated. It was possible to achieve 98 % gold and 93 % silver recovery within48 hours of ammonium thiosulphate leaching. This type of leaching is a better leaching procedure for recovery of gold and silver from PCBwaste than the classical toxic cyanide leaching. 84 % Cu, 82 % Fe, 77 % Al, 76 % Zn, 70 % Ni, 90 % Pd, 88 % Pb and 83 % Sn recovery ofthe accompanying metals was achieved, using sulphuric acid with hydrogen peroxide, sodium chloride and aqua regia. A four steps leachingprocess gave a very satisfactory yield and a more rapid kinetics for all observed metals solubilization than other technologies.

  11. Minimum Analytical Chemistry Requirements for Pit Manufacturing at Los Alamos National Laboratory; TOPICAL

    International Nuclear Information System (INIS)

    Moy, Ming M.; Leasure, Craig S.

    1998-01-01

    Analytical chemistry is one of several capabilities necessary for executing the Stockpile Stewardship and Management Program at Los Alamos National Laboratory (LANL). Analytical chemistry capabilities reside in the Chemistry Metallurgy Research (CMR) Facility and Plutonium Facility (TA-55). These analytical capabilities support plutonium recovery operations, plutonium metallurgy, and waste management. Analytical chemistry capabilities at both nuclear facilities are currently being configured to support pit manufacturing. This document summarizes the minimum analytical chemistry capabilities required to sustain pit manufacturing at LANL. By the year 2004, approximately$16 million will be required to procure analytical instrumentation to support pit manufacturing. In addition,$8.5 million will be required to procure glovebox enclosures. An estimated 50% increase in costs has been included for installation of analytical instruments and glovebox enclosures. However, no general and administrative (G and A) taxes have been included. If an additional 42.5/0 G and A tax were to be incurred, approximately$35 million would be required over the next five years to prepare analytical chemistry to support a 50-pit-per-year manufacturing capability by the year 2004

  12. Direct conversion of plutonium metal, scrap, residue, and transuranic waste to glass

    International Nuclear Information System (INIS)

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.; Malling, J.F.; Rudolph, J.

    1995-01-01

    A method for the direct conversion of metals, ceramics, organics, and amorphous solids to borosilicate glass has been invented. The process is called the Glass Material Oxidation and Dissolution System (GMODS). Traditional glass-making processes can convert only oxide materials to glass. However, many wastes contain complex mixtures of metals, ceramics, organics, and amorphous solids. Conversion of such mixtures to oxides followed by their conversion to glass is often impractical. GMODS may create a practical method to convert such mixtures to glass. Plutonium-containing materials (PCMS) exist in many forms, including metals, ceramics, organics, amorphous solids, and mixtures thereof. These PCMs vary from plutonium metal to filters made of metal, organic binders, and glass fibers. For storage and/or disposal of PCMS, it is desirable to convert PCMs to borosilicate glass. Borosilicate glass is the preferred repository waste form for high-level waste (HLW) because of its properties. PCMs converted to a transuranic borosilicate homogeneous glass would easily pass all waste acceptance and storage criteria. Conversion of PCMs to a glass would also simplify safeguards by conversion of heterogeneous PCMs to homogeneous glass. Thermodynamic calculations and proof-of-principle experiments on the GMODS process with cerium (plutonium surrogate), uranium, stainless steel, aluminum, Zircaloy-2, and carbon were successfully conducted. Initial analysis has identified potential flowsheets and equipment. Major unknowns remain, but the preliminary data suggests that GMODS may be a major new treatment option for PCMs

  13. Behavior of radioactive metal surrogates under various waste combustion conditions

    International Nuclear Information System (INIS)

    Yang, Hee Chul; Lee, Jae Hee; Kim, Jung Guk; Yoo, Jae Hyung; Kim, Joon Hyung

    2002-01-01

    A laboratory investigation of the behavior of radioactive metals under the various waste combustion atmospheres was conducted to predict the parameters that influence their partitioning behavior during waste incineration. Neodymium, samarium, cerium, gadolinium, cesium and cobalt were used as non-radioactive surrogate metals that are representative of uranium, plutonium, americium, curium, radioactive cesium, and radioactive cobalt, respectively. Except for cesium, all of the investigated surrogate metal compounds converted into each of their stable oxides at medium temperatures from 400 to 900 .deg. C, under oxygen-deficient and oxygen-sufficient atmospheres (0.001-atm and 0.21-atm O 2 ). At high temperatures above 1,400 .deg. C, cerium, neodymium and samarium in the form of their oxides started to vaporize but the vaporization rates were very slow up to 1500 .deg. C. Inorganic chlorine (NaCl) as well as organic chlorine (PVC) did not impact the volatility of investigated Nd 2 O 3 , CoO and Cs 2 O. The results of laboratory investigations suggested that the combustion chamber operating parameters affecting the entrainment of particulate and filtration equipment operating parameters affecting particle collection efficiency be the governing parameters of alpha radionuclides partitioning during waste incineration

  14. A probability distribution model of tooth pits for evaluating time-varying mesh stiffness of pitting gears

    Science.gov (United States)

    Lei, Yaguo; Liu, Zongyao; Wang, Delong; Yang, Xiao; Liu, Huan; Lin, Jing

    2018-06-01

    Tooth damage often causes a reduction in gear mesh stiffness. Thus time-varying mesh stiffness (TVMS) can be treated as an indication of gear health conditions. This study is devoted to investigating the mesh stiffness variations of a pair of external spur gears with tooth pitting, and proposes a new model for describing tooth pitting based on probability distribution. In the model, considering the appearance and development process of tooth pitting, we model the pitting on the surface of spur gear teeth as a series of pits with a uniform distribution in the direction of tooth width and a normal distribution in the direction of tooth height, respectively. In addition, four pitting degrees, from no pitting to severe pitting, are modeled. Finally, influences of tooth pitting on TVMS are analyzed in details and the proposed model is validated by comparing with a finite element model. The comparison results show that the proposed model is effective for the TVMS evaluations of pitting gears.

  15. Present state of the design and realization of regional radioactive waste depositories and waste acceptance criteria for disposal

    International Nuclear Information System (INIS)

    Kortus, J.

    1988-01-01

    Surface type regional depositories for radioactive wastes from nuclear power plants are described in detail. The depository of the Mochovce nuclear power plant is located near the plant, that of the Dukovany nuclear power plant is directly on the premises of the plant. Particular attention is paid to the design of the monolithic reinforced concrete pits, draining of rainwater from their surface, draining of seeping rainwater from the pit environment by means of a double drainage system, and insulation of the pits against water. The construction of the Mochovce depository started in 1987; some experience gained from this activity is presented. The radioactive waste acceptance criteria for depositories of this kind, based on safety analysis, are given. (author). 2 figs

  16. Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site.

    Science.gov (United States)

    Adama, M; Esena, R; Fosu-Mensah, B; Yirenya-Tawiah, D

    2016-01-01

    Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag) in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (I geo) and pollution load indices (PLI) were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69), Pb (143.80), Cr (99.30), and Cd (7.54) in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites.

  17. Modeling the degradation of a metallic waste form intended for geologic disposal

    International Nuclear Information System (INIS)

    Bauer, T.H.; Morris, E.E.

    2007-01-01

    Nuclear reactors operating with metallic fuels have led to development of robust metallic waste forms intended to immobilize hazardous constituents in oxidizing environments. Release data from a wide range of tests where small waste form samples have been immersed in a variety of oxidizing solutions have been analyzed and fit to a mechanistically-derived 'logarithmic growth' form for waste form degradation. A bounding model is described which plausibly extrapolates these fits to long-term degradation in a geologic repository. The resulting empirically-fit degradation model includes dependence on solution pH, temperature, and chloride concentration as well as plausible estimates of statistical uncertainty. (authors)

  18. Estimation of Pb from metal and electroplating industrial waste by ...

    African Journals Online (AJOL)

    The concentration of lead in sediment and liquid waste samples of selected metal electroplating industries was measured by atomic absorption spectrophotometer. The data obtained revealed that lead content in liquid wastes varies in the range of 0.582-14.97 mg L-1 and 1.300-757.8 mg Kg-1 in sediments. Removal of ...

  19. RCRA Facility Investigation/Remedial Investigation Report with Baseline Risk Assessment for the Central Shops Burning/Rubble Pit (631-6G), Volume 1 Final

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    The Burning/Rubble Pits at the Savannah River Site were usually shallow excavations approximately 3 to 4 meters in depth. Operations at the pits consisted of collecting waste on a continuous basis and burning on a monthly basis. The Central Shops Burning/Rubble Pit 631- 6G (BRP6G) was constructed in 1951 as an unlined earthen pit in surficial sediments for disposal of paper, lumber, cans and empty galvanized steel drums. The unit may have received other materials such as plastics, rubber, rags, cardboard, oil, degreasers, or drummed solvents. The BRP6G was operated from 1951 until 1955. After disposal activities ceased, the area was covered with soil. Hazardous substances, if present, may have migrated into the surrounding soil and/or groundwater. Because of this possibility, the United States Environmental Protection Agency (EPA) has designated the BRP6G as a Solid Waste Management Unit (SWMU) subject to the Resource Conservation Recovery Act/Comprehensive Environmental Response, Compensation and Liability Act (RCRA/CERCLA) process.

  20. Pollution distribution of heavy metals in surface soil at an informal electronic-waste recycling site.

    Science.gov (United States)

    Fujimori, Takashi; Takigami, Hidetaka

    2014-02-01

    We studied distribution of heavy metals [lead (Pb), copper (Cu) and zinc (Zn)] in surface soil at an electronic-waste (e-waste) recycling workshop near Metro Manila in the Philippines to evaluate the pollution size (spot size, small area or the entire workshop), as well as to assess heavy metal transport into the surrounding soil environment. On-site length-of-stride-scale (~70 cm) measurements were performed at each surface soil point using field-portable X-ray fluorescence (FP-XRF). The surface soil at the e-waste recycling workshop was polluted with Cu, Zn and Pb, which were distributed discretely in surface soil. The site was divided into five areas based on the distance from an entrance gate (y-axis) of the e-waste recycling workshop. The three heavy metals showed similar concentration gradients in the y-axis direction. Zn, Pb and Cu concentrations were estimated to decrease to half of their maximum concentrations at ~3, 7 and 7 m from the pollution spot, respectively, inside the informal e-waste recycling workshop. Distance from an entrance may play an important role in heavy metal transport at the soil surface. Using on-site FP-XRF, we evaluated the metal ratio to characterise pollution features of the solid surface. Variability analysis of heavy metals revealed vanishing surficial autocorrelation over metre ranges. Also, the possibility of concentration prediction at unmeasured points using geostatistical kriging was evaluated, and heavy metals had a relative "small" pollution scales and remained inside the original workshop compared with toxic organohalogen compounds. Thus, exposure to heavy metals may directly influence the health of e-waste workers at the original site rather than the surrounding habitat and environmental media.

  1. Application of biotechnology in management of industrial wastes containing toxic metals

    Energy Technology Data Exchange (ETDEWEB)

    Barton, L L; Fekete, F A; Huybrechts, M M.E. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Biology; Sillerud, L O [Los Alamos National Lab., NM (United States); Blacke, II, R C [Meharry Medical Coll., Nashville, TN (United States); Pigg, C J [Sandia National Labs., Albuquerque, NM (United States)

    1994-01-01

    The role of microorganisms in transformation and absorption of metals in the environment is examined in this article. Understanding the metabolic processes by which microorganisms interact with toxic metals is paramount for any bioremediation process dealing with restoration of toxic waste site. Bacteria, fungi, and yeast that displayed resistance to lead, mercury, or chromium were isolated from the environment. Cotolerance studies revealed that many of these organisms could grow in high concentrations of several different toxic elements. Transformation of chromium, mercury, and lead was displayed by means of the isolated bacterial strains. Data regarding the activities of these organisms can provide a basis for use of metal/tolerant organisms in bioremediation of toxic wastes containing mercury, chromium, and lead. (author) 1 fig., 7 tabs., 28 refs.

  2. Low temperature incineration of mixed wastes using bulk metal oxide catalysts

    International Nuclear Information System (INIS)

    Gordon, M.J.; Gaur, S.; Kelkar, S.; Baldwin, R.M.

    1996-01-01

    Volume reduction of low-level mixed wastes from former nuclear weapons facilities is a significant environmental problem. Processing of these materials presents unique scientific and engineering problems due to the presence of minute quantities of radionuclides which must be contained and concentrated for later safe disposal. Low-temperature catalytic incineration is one option that has been utilized at the Rocky Flats facility for this purpose. This paper presents results of research regarding evaluation of bulk metal oxides as catalysts for low-temperature incineration of carbonaceous residues which are typical by-products of fluidized bed combustion of mixed wastes under oxygen-lean conditions. A series of 14 metal oxides were screened in a thermogravimetric analyzer, using on-line mass spectrometry for speciation of reaction product gases. Catalyst evaluation criteria focused on the thermal-redox activity of the metals using both carbon black and PVC char as surrogate waste materials. Results indicated that metal oxides which were P-type semiconductor materials were suitable as catalysts for this application. Oxides of cobalt, molybdenum, vanadium, and manganese were found to be particularly stable and active catalysts under conditions specific to this process (T<650C, low oxygen partial pressures). Bench-scale evaluation of these metal oxides with respect to stability to chlorine (HCl) attack was carried out at 550C using a TG/MS system. Cobalt oxide was found to be resistant to metal loss in a HCl/He gaseous environment while metal loss from Mo, Mn, and V-based catalysts was moderate to severe. XRD and SEM/EDX analysis of spent Co catalysts indicated the formation of non-stoichiometric cobalt chlorides. Regeneration of chlorinated cobalt was found to successfully restore the low-temperature combustion activity to that of the fresh metal oxide

  3. Tank Riser Pit Decontamination System (Pit Viper) Return on Investment and Break-Even Analysis

    International Nuclear Information System (INIS)

    Young, Joan K.; Weimar, Mark R.; Balducci, Patrick J.; Fassbender, Linda L.; Hernandez, Melissa

    2003-01-01

    This study assessed the cost benefit of Pit Viper deployment for 80 tank farm pits between October 1, 2003 and September 30, 2012 under the technical baseline for applicable double-shell tank (DST) and single-shell tank (SST) projects. After this assessment had been completed, the U.S. Department of Energy (DOE) Richland Operations Office (RL) and Office of River Protection (ORP) published the Hanford Performance Management Plan (August 2003), which accelerated the schedule for SST retrieval. Then, DOE/CH2M HILL contract modification M064 (October 2002) and The Integrated Mission Acceleration Plan (March 2003) further accelerated SST retrieval and closure schedules. Twenty-six to 40 tanks must be retrieved by 2006. Thus the schedule for SST pit entries is accelerated and the number of SST pit entries is increased. This study estimates the return on investment (ROI) and the number of pits where Pit Viper deployment would break even or save money over current manual practices. The results of the analysis indicate a positive return on the federal investment for deployment of the Pit Viper provided it is used on a sufficient number of pits

  4. Informal e-waste recycling: environmental risk assessment of heavy metal contamination in Mandoli industrial area, Delhi, India.

    Science.gov (United States)

    Pradhan, Jatindra Kumar; Kumar, Sudhir

    2014-01-01

    Nowadays, e-waste is a major source of environmental problems and opportunities due to presence of hazardous elements and precious metals. This study was aimed to evaluate the pollution risk of heavy metal contamination by informal recycling of e-waste. Environmental risk assessment was determined using multivariate statistical analysis, index of geoaccumulation, enrichment factor, contamination factor, degree of contamination and pollution load index by analysing heavy metals in surface soils, plants and groundwater samples collected from and around informal recycling workshops in Mandoli industrial area, Delhi, India. Concentrations of heavy metals like As (17.08 mg/kg), Cd (1.29 mg/kg), Cu (115.50 mg/kg), Pb (2,645.31 mg/kg), Se (12.67 mg/kg) and Zn (776.84 mg/kg) were higher in surface soils of e-waste recycling areas compared to those in reference site. Level exceeded the values suggested by the US Environmental Protection Agency (EPA). High accumulations of heavy metals were also observed in the native plant samples (Cynodon dactylon) of e-waste recycling areas. The groundwater samples collected form recycling area had high heavy metal concentrations as compared to permissible limit of Indian Standards and maximum allowable limit of WHO guidelines for drinking water. Multivariate analysis and risk assessment studies based on total metal content explains the clear-cut differences among sampling sites and a strong evidence of heavy metal pollution because of informal recycling of e-waste. This study put forward that prolonged informal recycling of e-waste may accumulate high concentration of heavy metals in surface soils, plants and groundwater, which will be a matter of concern for both environmental and occupational hazards. This warrants an immediate need of remedial measures to reduce the heavy metal contamination of e-waste recycling sites.

  5. Repair procedure used in removing corroded pits in the distillation towers of the Getulio Vargas Refinery Unit 2100

    Energy Technology Data Exchange (ETDEWEB)

    Lordelos, H.M.; Santin, J.L.

    1977-07-01

    A description is given of the corrosion pits on ASTM A240, Type 405 steel cladded to carbon steel plates used in Petroleo Brasileiro S.A.'s Getulio Vargas Refinery Unit 2100 distillation towers; the repair procedure used, including sand blasting of the corroded surfaces, grinding of the pits, and welding of those pits whose depth was above a maximum limit, and the use of liquid penetrant to check the repairs made; and hydrostatic testing of the T2201 catalytic cracking unit, which used also cladded metals and on which the pits were much smaller in size and number than those on the distillation units.

  6. Pit Water Storage Ottrupgaard

    DEFF Research Database (Denmark)

    Heller, Alfred

    2000-01-01

    The pit water storage, a seasonal thermal storage, was built in 1993 with floating lid and hybrid clay-polymer for pit lining. The storage was leaking severe and solutions were to be found. In the paper solutions for pit lining and floating lids are discussed, cost estimations given and coming...

  7. ARIES pit disassembly-safeguards issues for transparency

    International Nuclear Information System (INIS)

    Fearey, B.L.; Cremers, T.L.

    1995-01-01

    Historic changes are now occurring in U.S. nonproliferation and arms control policy. The quantity of nuclear weapons required to provide a deterrence has decreased (especially with the end of the Cold War). Further, various bilateral and multilateral treaties now require the removal of numerous nuclear weapons from the U.S. stockpile. Although the removal of such weapons appears straightforward, the final disposition of the surplus weapons-grade nuclear material must be carefully considered. Domestically, several plutonium disposition plans are now under consideration concerning long-term safety, materials accounting, environmental impact, accessibility, and long-term containment. The Automated Retirement and Integrated Extraction System (ARIES) currently under development at Los Alamos National Laboratory is one such disposition method for the disassembly of plutonium weapons components (pits). The ARIES system integrates and automates several features: disassembly of pits, consolidation of the plutonium material, on-line measurement of final products, waste streams, and long-term packaging. Clearly, in any plutonium disposition plan, the safeguards aspects of materials control and accounting and the security aspects must be carefully considered and evaluated

  8. Results of detailed ground geophysical surveys for locating and differentiating waste structures in waste management area 'A' at Chalk River Laboratories, Ontario

    International Nuclear Information System (INIS)

    Tomsons, D.K.; Street, P.J.; Lodha, G.S.

    1999-01-01

    Waste Management Area 'A' (WMA 'A'), located in the outer area of the Chalk River Laboratories (CRL) was in use as a waste burial site from 1946 to 1955. Waste management structures include debris-filled trenches, concrete bunkers and miscellaneous contaminated solid materials, and ditches and pits used for liquid dispersal. In order to update historical records, it was proposed to conduct detailed ground geophysical surveys to define the locations of waste management structures in WMA 'A', assist in planning of the drilling and sampling program to provide ground truth for the geophysics investigation and to predict the nature and locations of unknown/undefined shallow structures. A detailed ground geophysical survey grid was established with a total of 127 grid lines, oriented NNE and spaced one metre apart. The geophysical surveys were carried out during August and September, 1996. The combination of geophysical tools used included the Geonics EM61 metal detector, the GSM-19 magnetometer/gradiometer and a RAMAC high frequency ground penetrating radar system. The geophysical surveys were successful in identifying waste management structures and in characterizing to some extent, the composition of the waste. The geophysical surveys are able to determine the presence of most of the known waste management structures, especially in the western and central portions of the grid which contain the majority of the metallic waste. The eastern portion of the grid has a completely different geophysical character. While historical records show that trenches were dug, they are far less evident in the geophysical record. There is clear evidence for a trench running between lines 30E and 63E at 70 m. There are indications from the radar survey of other trench-like structures in the eastern portion. EM61 data clearly show that there is far less metallic debris in the eastern portion. The geophysical surveys were also successful in identifying previously unknown locations of waste

  9. Аpplying of Explosives of the Type an-fo and Slurry in the Open Pit Mine "Bucim"

    OpenAIRE

    Dambov, Risto; Nikolic, Miroslav; Dambov, Ilija

    2012-01-01

    In this paper shows the way of application of ANFO and SLURRY bulk explosives and blasting methods that are characteristic for this open pit mine. According to the physical - mechanical characteristics of the working environment and condition of the blast hole are defining some parameters for each series separately. In this open pit are defined 5(five) different working environments - rocks with copper mineralization (0,25%Cu) or rocks waste. According to the effects of blasting are make cert...

  10. The corrosion properties of Zr-Cr-NM alloy metallic waste form for longterm disposal

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Youb; Jang, Seon Ah; Eun, Hee Chul; Choi, Jung Hoon; Lee, Ki Rak; Park, Hwan Seo; Ahn, Do Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2017-06-15

    KAERI is conducting research on spent cladding hulls and additive metals to generate a solidifcation host matrix for the noble metal fssion product waste in anode sludge from the electro-refning process to minimize the volume of waste that needs to be disposed of. In this study, alloy compositions Zr-17Cr, Zr-22Cr, and Zr-27Cr were prepared with or without eight noble metals representing fuel waste using induction melting. The microstructures of the resulting alloys were characterized and electrochemical corrosion tests were conducted to evaluate their corrosion characteristics. All the compositions had better corrosion characteristics than other Zr-based alloys that were evaluated for comparison. Analysis of the leach solution after the corrosion test of the Zr-22Cr-8NM specimen indicated that the noble metals were not leached during corrosion under 500 mV imposed voltage, which simulates a highly oxidizing disposal environment. The results of this study confrm that Zr-Cr based compositions will likely serve as chemically stable waste forms.

  11. Corrosion Evaluation of INTEC Waste Storage Tank WM-182

    International Nuclear Information System (INIS)

    Dirk, W. J.; Anderson, P. A.

    1999-01-01

    Irradiated nuclear fuel has been stored and reprocessed at the Idaho National Engineering and Environmental Laboratory since 1953 using facilities located at the Idaho Nuclear Technology and Engineering Center (INTEC). This reprocessing produced radioactive liquid waste which was stored in the Tank Farm. The INTEC Tank Farm consists of eleven vaulted 300,000-gallon underground tanks including Tank WM-182. Tank WM-182 was put into service in 1955, has been filled four times, and has contained aluminum and zirconium fuel reprocessing wastes as well as sodium bearing waste. A program to monitor corrosion in the waste tanks was initiated in 1953 when the first of the eleven Tank Farm tanks was placed in service. Austenitic stainless steel coupons representative of the materials of construction of the tanks are used to monitor internal tank corrosion. This report documents the final inspection of the WM-182 corrosion coupons. Physical examination of the welded corrosion test coupons exposed to the tank bottom conditions of Tank WM-182 revealed very light uniform corrosion. Examination of the external surfaces of the extruded pipe samples showed very light uniform corrosion with slight indications of preferential attack parallel to extrusion marks and start of end grain attack of the cut edges. These indications were only evident when examined under stereo microscope at magnifications of 20X and above. There were no definite indications of localized corrosion, such as cracking, pitting, preferential weld attack, or weld heat affected zone attack on either the welded or extruded coupons. Visual examination of the coupon support cables, where they were not encased in plastic, failed to reveal any indication of liquid-liquid interface attack of any crevice corrosion. Based on the WM-182 coupon evaluations, which have occurred throughout the life of the tank, the metal loss from the tank wall due to uniform corrosion is not expected to exceed 5.5 x 10-1 mil (0.00 055 inch

  12. Open Pit Water Control Safety A Case Of Nchanga Open Pit Mine Zambia

    Directory of Open Access Journals (Sweden)

    Silwamba C

    2015-08-01

    Full Text Available Abstract Mining in Chingola Zambia started underground in 1931 and was catastrophically flooded and closed. The present Nchanga Underground Mine NUG started in 1937. The Nchanga Open Pit NOP mine started in 1955 situated to the west of NUG and partially overlying it. Open pit water control safety operations in the Nchanga-Chingola area have successfully enabled the safe extraction of millions of tonnes of copper ore annually over the past 60 years from NUG mining as well as the NOP. At the start Nchanga mining license surface already had NUG and many watershed divides with the Nchanga and Chingola streams being the main streams feeding into Zambias second largest river Kafue river and 42 of the year was characterised by heavy rains ranging between 800mm to 1300mm per annum. In this paper the presence of very significant amounts of seasonal rain and subsurface water in the mining area was identified as both a curse and a blessing. An excess in seasonal rain and subsurface water would disrupt both open pit and underground mining operations. In order for NOP to be operated successfully stable and free from flooding coping water management tactics were adopted from 1955 to 2015 including 1. Underground mine pump chamber pumping system 2. Piezometer instrumented boreholes 3. Underground mine 1500-ft sub-haulage east borehole dewatering beneath the open pit 4. Nchanga and Chingola stream diversionary tunnel and open drains 5. Nchanga stream causeway and embankment dam in the Matero School Golf Club area 6. Pit perimeter borehole pumping 7. Outer and inner pit perimeter drains and bund walls 8. In-pit ramp side drains 9. In-pit sub-horizontal borehole geo-drains and water and 10. Pit bottom sump pumps. Application of grout curtains along the Vistula River Poland was noted as a possibility in the right circumstances although it had never been used at Nchanga Open Pit. An additional conclusion was that forward health safety and environmental end

  13. Informal E-waste recycling in developing countries: review of metal(loid)s pollution, environmental impacts and transport pathways.

    Science.gov (United States)

    Ackah, Michael

    2017-11-01

    Crude or primitive recycling practices are often adopted in material resource recovery from E-waste in developing nations. Significant human health and environmental impacts may occur because of such practices. Literature on metal(loid)s pollution during E-waste processing is fragmented. Here, I review the health and environmental impacts of E-waste recycling operations and transport pathways of metal(loid)s, dispersed during operations. This paper is organised into five sections. Section 1 relates to the background of global E-waste generation and legal/illegal trade, citing specific cases from Ghana and other developing nations. Section 2 provides a brief information on sources of metal(loid)s in E-waste. Section 3 describes characteristics of informal E-waste recycling operations in developing nations. Section 4 examines the health and environmental impacts in E-waste recycling while section 5 evaluates major transport pathways of metal(loid)s contaminants.

  14. Insights into metals in individual fine particles from municipal solid waste using synchrotron radiation-based micro-analytical techniques.

    Science.gov (United States)

    Zhu, Yumin; Zhang, Hua; Shao, Liming; He, Pinjing

    2015-01-01

    Excessive inter-contamination with heavy metals hampers the application of biological treatment products derived from mixed or mechanically-sorted municipal solid waste (MSW). In this study, we investigated fine particles of heavy metal content, using bulk detection techniques. A total of 17 individual fine particles were evaluated using synchrotron radiation-based micro-X-ray fluorescence and micro-X-ray diffraction. We also discussed the association, speciation and source apportionment of heavy metals. Metals were found to exist in a diffuse distribution with heterogeneous intensities and intense hot-spots of metals revealed the potential sources of fine particles from size-reduced waste fractions (such as scraps of organic wastes or ceramics) or from the importation of other particles. The diverse sources of heavy metal pollutants within the fine particles suggested that separate collection and treatment of the biodegradable waste fraction (such as food waste) is a preferable means of facilitating the beneficial utilization of the stabilized products. Copyright © 2014. Published by Elsevier B.V.

  15. Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site

    Directory of Open Access Journals (Sweden)

    M. Adama

    2016-01-01

    Full Text Available Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (Igeo and pollution load indices (PLI were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69, Pb (143.80, Cr (99.30, and Cd (7.54 in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites.

  16. Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site

    Science.gov (United States)

    Adama, M.; Esena, R.; Fosu-Mensah, B.; Yirenya-Tawiah, D.

    2016-01-01

    Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag) in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (I geo) and pollution load indices (PLI) were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69), Pb (143.80), Cr (99.30), and Cd (7.54) in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites. PMID:27034685

  17. The effect of waste water treatment on river metal concentrations: removal or enrichment?

    NARCIS (Netherlands)

    Teuchies, J.; Bervoets, L.; Cox, T.J.S.; Meire, P.; de Deckere, E.

    2011-01-01

    Purpose Discharge of untreated domestic and industrial waste in many European rivers resulted in low oxygen concentrations and contamination with trace metals, often concentrated in sediments. Under these anoxic conditions, the formation of insoluble metal sulfides is known to reduce metal

  18. The Pit and the Safety Pendulum

    Energy Technology Data Exchange (ETDEWEB)

    Nitschke, Robert Leon; Ramos, Amadeo Gabriel

    2000-11-01

    The hypothesis of this paper is that the safety analysis pendulum has swung considerably in the direction of increasingly complex and lengthy safety evaluations and intense reviews during the past 30 years. The test of this hypothesis will be a review of the safety analysis conducted for various activities associated with the retrieval of transuranic radioactive waste from burial pits at a National Laboratory site over a span of 30 years. The examination will focus on the safety aspects and the safety analysis that was conducted for the projects. At the conclusion of this examination, the paper will identify five reasons why the changes have taken place.

  19. Adsorption mechanisms of removing heavy metals and dyes from aqueous solution using date pits solid adsorbent

    International Nuclear Information System (INIS)

    Al-Ghouti, Mohammad A.; Li, Juiki; Salamh, Yousef; Al-Laqtah, Nasir; Walker, Gavin; Ahmad, Mohammad N.M.

    2010-01-01

    A potential usefulness of raw date pits as an inexpensive solid adsorbent for methylene blue (MB), copper ion (Cu 2+ ), and cadmium ion (Cd 2+ ) has been demonstrated in this work. This work was conducted to provide fundamental information from the study of equilibrium adsorption isotherms and to investigate the adsorption mechanisms in the adsorption of MB, Cu 2+ , and Cd 2+ onto raw date pits. The fit of two models, namely Langmuir and Freundlich models, to experimental data obtained from the adsorption isotherms was checked. The adsorption capacities of the raw date pits towards MB and both Cu 2+ and Cd 2+ ions obtained from Langmuir and Freundlich models were found to be 277.8, 35.9, and 39.5 mg g -1 , respectively. Surface functional groups on the raw date pits surface substantially influence the adsorption characteristics of MB, Cu 2+ , and Cd 2+ onto the raw date pits. The Fourier transform infrared spectroscopy (FTIR) studies show clear differences in both absorbances and shapes of the bands and in their locations before and after solute adsorption. Two mechanisms were observed for MB adsorption, hydrogen bonding and electrostatic attraction, while other mechanisms were observed for Cu 2+ and Cd 2+ . For Cu 2+ , binding two cellulose/lignin units together is the predominant mechanism. For Cd 2+ , the predominant mechanism is by binding itself using two hydroxyl groups in the cellulose/lignin unit.

  20. Removal and recovery of radionuclides and toxic metals from wastes, soils and materials

    International Nuclear Information System (INIS)

    Francis, A.J.

    1993-07-01

    A process has been developed at Brookhaven National Laboratory (BNL) for the removal of metals and radionuclides from contaminated materials, soils, and waste sites (Figure 1). In this process, citric acid, a naturally occurring organic complexing agent, is used to extract metals such as Ba, Cd, Cr, Ni, Zn, and radionuclides Co, Sr, Th, and U from solid wastes by formation of water soluble, metal-citrate complexes. Citric acid forms different types of complexes with the transition metals and actinides, and may involve formation of a bidentate, tridentate, binuclear, or polynuclear complex species. The extract containing radionuclide/metal complex is then subjected to microbiological degradation followed by photochemical degradation under aerobic conditions. Several metal citrate complexes are biodegraded and the metals are recovered in a concentrated form with the bacterial biomass. Uranium forms binuclear complex with citric acid and is not biodegraded. The supernatant containing uranium citrate complex is separated and upon exposure to light, undergoes rapid degradation resulting in the formation of an insoluble, stable polymeric form of uranium. Uranium is recovered as a precipitate (uranium trioxide) in a concentrated form for recycling or for appropriate disposal. This treatment process, unlike others which use caustic reagents, does not create additional hazardous wastes for disposal and causes little damage to soil which can then be returned to normal use

  1. THE INFLUENCE OF SELECTED FACTORS ON THE LEACHING OF HEAVY METALS FROM SMELTER WASTE

    OpenAIRE

    Kamila Mizerna; Anna Król

    2015-01-01

    The paper presents the results of leaching research of selected heavy metals (Pb, Cu, Zn, Ni, Cd, Cr) from industrial waste. The impact of waste fragmentation on the level of heavy metals leaching was analyzed. The decrease of copper and zinc release and the increase of nickel leaching were observed with increasing grain size fraction of waste. Furthermore, release of contaminants in different ratio of liquid to solid (L/S = 10 dm3/kg and 2 dm3/kg) was studied. Higher concentrations of heavy ...

  2. Heavy metal removal from waste waters by ion flotation

    OpenAIRE

    Polat, Hürriyet; Erdoğan, D.

    2007-01-01

    Flotation studies were carried out to investigate the removal of heavy metals such as copper (II), zinc (II), chromium (III) and silver (I) from waste waters. Various parameters such as pH, collector and frother concentrations and airflow rate were tested to determine the optimum flotation conditions. Sodium dodecyl sulfate and hexadecyltrimethyl ammonium bromide were used as collectors. Ethanol and methyl isobutyl carbinol (MIBC) were used as frothers. Metal removal reached about 74% under o...

  3. Towards zero waste production in the minerals and metals sector

    Science.gov (United States)

    Rankin, William J.

    The production of mineral and metal commodities results in large quantities of wastes (solid, liquid and gaseous) at each stage of value-adding — from mining to manufacturing. Waste production (both consumer and non-consumer) is a major contributor to environmental degradation. Approaches to waste management in the minerals industry are largely `after the event'. These have moved progressively from foul-and-flee to dilute-and-disperse to end end-of-pipe treatments. There is now a need to move to approaches which aim to reduce or eliminate waste production at source. Modern waste management strategies include the application of cleaner production principles, the use of wastes as raw materials, the reengineering of process flowsheets to minimise waste production, and use of industrial symbioses through industrial ecology to convert wastes into useful by-products. This paper examines how these can be adopted by the minerals industry, with some recent examples. The financial, technical, systemic and regulatory drivers and barriers are also examined.

  4. Electrochemical corrosion testing of metal waste forms

    International Nuclear Information System (INIS)

    Abraham, D. P.; Peterson, J. J.; Katyal, H. K.; Keiser, D. D.; Hilton, B. A.

    1999-01-01

    Electrochemical corrosion tests have been conducted on simulated stainless steel-zirconium (SS-Zr) metal waste form (MWF) samples. The uniform aqueous corrosion behavior of the samples in various test solutions was measured by the polarization resistance technique. The data show that the MWF corrosion rates are very low in groundwaters representative of the proposed Yucca Mountain repository. Galvanic corrosion measurements were also conducted on MWF samples that were coupled to an alloy that has been proposed for the inner lining of the high-level nuclear waste container. The experiments show that the steady-state galvanic corrosion currents are small. Galvanic corrosion will, hence, not be an important mechanism of radionuclide release from the MWF alloys

  5. Valorization of titanium metal wastes as tanning agent used in leather industry

    Energy Technology Data Exchange (ETDEWEB)

    Crudu, Marian, E-mail: mariancrudu@yahoo.com [The National Research and Development Institute for Textiles and Leather – Division Leather and Footwear Research Institute, 93 Ion Minulescu Str., Bucharest (Romania); Deselnicu, Viorica, E-mail: viorica.deselnicu@icpi.ro [The National Research and Development Institute for Textiles and Leather – Division Leather and Footwear Research Institute, 93 Ion Minulescu Str., Bucharest (Romania); Deselnicu, Dana Corina, E-mail: d_deselnicu@yahoo.com [University Politehnica Bucharest, Splaiul Independentei Nr. 313, Sector 6, RO-060042 Bucharest (Romania); Albu, Luminita, E-mail: luminita.albu@gmail.com [The National Research and Development Institute for Textiles and Leather – Division Leather and Footwear Research Institute, 93 Ion Minulescu Str., Bucharest (Romania)

    2014-10-15

    Highlights: • Valorization of titanium wastes which cannot be recycled in metallurgical industry. • Transferring Ti waste into raw materials for obtaining Ti based tanning agent. • Characterization of new Ti based tanning agents and leather tanned with them. • Characterization of sewage waste water and sludge resulted from leather manufacture. • Analysis of the impact of main metal component of Ti waste. - Abstract: The development of new tanning agents and new technologies in the leather sector is required to cope with the increasingly higher environmental pressure on the current tanning materials and processes such as tanning with chromium salts. In this paper, the use of titanium wastes (cuttings) resulting from the process of obtaining highly pure titanium (ingots), for the synthesis of new tanning agent and tanning bovine hides with new tanning agent, as alternative to tanning with chromium salts are investigated. For this purpose, Ti waste and Ti-based tanning agent were characterized for metal content by inductively coupled plasma mass spectrometry (ICP-MS) and chemical analysis; the tanned leather (wet white leather) was characterized by Scanning Electron Microscope/Energy Dispersive Using X-ray (Analysis). SEM/EDX analysis for metal content; Differential scanning calorimetric (DSC), Micro-Hot-Table and standard shrinkage temperature showing a hydrothermal stability (ranged from 75.3 to 77 °C) and chemical analysis showing the leather is tanned and can be processed through the subsequent mechanical operations (splitting, shaving). On the other hand, an analysis of major minor trace substances from Ti-end waste (especially vanadium content) in new tanning agent and wet white leather (not detected) and residue stream was performed and showed that leachability of vanadium is acceptable. The results obtained show that new tanning agent obtained from Ti end waste can be used for tanning bovine hides, as eco-friendly alternative for chrome tanning.

  6. Valorization of titanium metal wastes as tanning agent used in leather industry

    International Nuclear Information System (INIS)

    Crudu, Marian; Deselnicu, Viorica; Deselnicu, Dana Corina; Albu, Luminita

    2014-01-01

    Highlights: • Valorization of titanium wastes which cannot be recycled in metallurgical industry. • Transferring Ti waste into raw materials for obtaining Ti based tanning agent. • Characterization of new Ti based tanning agents and leather tanned with them. • Characterization of sewage waste water and sludge resulted from leather manufacture. • Analysis of the impact of main metal component of Ti waste. - Abstract: The development of new tanning agents and new technologies in the leather sector is required to cope with the increasingly higher environmental pressure on the current tanning materials and processes such as tanning with chromium salts. In this paper, the use of titanium wastes (cuttings) resulting from the process of obtaining highly pure titanium (ingots), for the synthesis of new tanning agent and tanning bovine hides with new tanning agent, as alternative to tanning with chromium salts are investigated. For this purpose, Ti waste and Ti-based tanning agent were characterized for metal content by inductively coupled plasma mass spectrometry (ICP-MS) and chemical analysis; the tanned leather (wet white leather) was characterized by Scanning Electron Microscope/Energy Dispersive Using X-ray (Analysis). SEM/EDX analysis for metal content; Differential scanning calorimetric (DSC), Micro-Hot-Table and standard shrinkage temperature showing a hydrothermal stability (ranged from 75.3 to 77 °C) and chemical analysis showing the leather is tanned and can be processed through the subsequent mechanical operations (splitting, shaving). On the other hand, an analysis of major minor trace substances from Ti-end waste (especially vanadium content) in new tanning agent and wet white leather (not detected) and residue stream was performed and showed that leachability of vanadium is acceptable. The results obtained show that new tanning agent obtained from Ti end waste can be used for tanning bovine hides, as eco-friendly alternative for chrome tanning

  7. Effective Recovery of Vanadium from Oil Refinery Waste into Vanadium-Based Metal-Organic Frameworks.

    Science.gov (United States)

    Zhan, Guowu; Ng, Wei Cheng; Lin, Wenlin Yvonne; Koh, Shin Nuo; Wang, Chi-Hwa

    2018-03-06

    Carbon black waste, an oil refinery waste, contains a high concentration of vanadium(V) leftover from the processing of crude oil. For the sake of environmental sustainability, it is therefore of interest to recover the vanadium as useful products instead of disposing of it. In this work, V was recovered in the form of vanadium-based metal-organic frameworks (V-MOFs) via a novel pathway by using the leaching solution of carbon black waste instead of commercially available vanadium chemicals. Two different types of V-MOFs with high levels of crystallinity and phase purity were fabricated in very high yields (>98%) based on a coordination modulation method. The V-MOFs exhibited well-defined and controlled shapes such as nanofibers (length: > 10 μm) and nanorods (length: ∼270 nm). Furthermore, the V-MOFs showed high catalytic activities for the oxidation of benzyl alcohol to benzaldehyde, indicating the strong potential of the waste-derived V-MOFs in catalysis applications. Overall, our work offers a green synthesis pathway for the preparation of V-MOFs by using heavy metals of industrial waste as the metal source.

  8. Noble metal behavior during melting of simulated high-level nuclear waste glass feeds

    International Nuclear Information System (INIS)

    Anderson, L.D.; Dennis, T.; Elliott, M.L.; Hrma, P.

    1993-04-01

    Noble metals and their oxides can settle in waste glass melters and cause electrical shorting. Simulated waste feeds from Hanford, Savannah River, and Germany were heat treated for 1 hour in a gradient furnace at temperatures ranging from approximately 600 degrees C--1000 degrees C and examined by electron microscopy to determine shapes, sizes, and distribution of noble metal particles as a function of temperature. Individual noble metal particles and agglomerates of rhodium (Rh), ruthenium (RuO 2 ), and palladium (Pd), as well as their alloys, were seen. the majority of particles and agglomerates were generally less than 10 microns; however, large agglomerations (up to 1 mm) were found in the German feed. Detailed particle distribution and characterization was performed for a Hanford waste to provide input to computer modeling of particle settling in the melter

  9. Heavy Metal Leaching as Affected by Long-Time Organic Waste Fertilizer Application.

    Science.gov (United States)

    Lekfeldt, Jonas Duus Stevens; Holm, Peter E; Kjærgaard, Charlotte; Magid, Jakob

    2017-07-01

    The recycling of urban waste products as fertilizers in agriculture may introduce contaminants such as heavy metals into soil that may leach and contaminate groundwater. In the present study, we investigated the leaching of heavy metals from intact soil cores collected in the long-term agricultural field trial CRUCIAL. At the time of sampling, the equivalent of >100 yr of urban waste fertilizers following Danish legislation had been applied. The leaching of Cu was significantly increased in the treatments receiving organic waste products compared with the unfertilized control but remained below the permissible level following Danish drinking water guidelines. The leaching of Cu was controlled primarily by the topsoil Cu content and by the leaching of dissolved organic carbon (DOC) but at the same time significantly correlated with leaching of colloids in soils that had not received fertilizer or had received an organic fertilizer with a low concentration of Cu. The leaching of Zn, Cd, and Co was not significantly increased in urban waste-fertilized treatments. The leaching of Mo was elevated in accelerated waste treatments (both agricultural and urban), and the leaching of Mo was linked to the leaching of DOC. Since leaching of Cr and Pb was strongly linked to the level of colloid leaching, leaching of these metals was reduced in the urban waste treatments. Overall, the results presented should not raise concern regarding the agricultural use of urban waste products in agriculture as long as the relevant guidelines are followed. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  10. Heavy metal removal from waste waters by ion flotation.

    Science.gov (United States)

    Polat, H; Erdogan, D

    2007-09-05

    Flotation studies were carried out to investigate the removal of heavy metals such as copper (II), zinc (II), chromium (III) and silver (I) from waste waters. Various parameters such as pH, collector and frother concentrations and airflow rate were tested to determine the optimum flotation conditions. Sodium dodecyl sulfate and hexadecyltrimethyl ammonium bromide were used as collectors. Ethanol and methyl isobutyl carbinol (MIBC) were used as frothers. Metal removal reached about 74% under optimum conditions at low pH. At basic pH it became as high as 90%, probably due to the contribution from the flotation of metal precipitates.

  11. Comparison of soil heavy metal pollution caused by e-waste recycling activities and traditional industrial operations.

    Science.gov (United States)

    He, Kailing; Sun, Zehang; Hu, Yuanan; Zeng, Xiangying; Yu, Zhiqiang; Cheng, Hefa

    2017-04-01

    The traditional industrial operations are well recognized as an important source of heavy metal pollution, while that caused by the e-waste recycling activities, which have sprouted in some developing countries, is often overlooked. This study was carried out to compare the status of soil heavy metal pollution caused by the traditional industrial operations and the e-waste recycling activities in the Pearl River Delta, and assess whether greater attention should be paid to control the pollution arising from e-waste recycling activities. Both the total contents and the chemical fractionation of major heavy metals (As, Cr, Cd, Ni, Pb, Cu, and Zn) in 50 surface soil samples collected from the e-waste recycling areas and 20 soil samples from the traditional industrial zones were determined. The results show that the soils in the e-waste recycling areas were mainly polluted by Cu, Zn, As, and Cd, while Cu, Zn, As, Cd, and Pb were the major heavy metals in the soils from the traditional industrial zones. Statistical analyses consistently show that Cu, Cd, Pb, and Zn in the surface soils from both types of sites were contributed mostly by human activities, while As, Cr, and Ni in the soils were dominated by natural background. No clear distinction was found on the pollution characteristic of heavy metals in the surface soils between the e-waste recycling areas and traditional industrial zones. The potential ecological risk posed by heavy metals in the surface soils from both types of sites, which was dominated by that from Cd, ranged from low to moderate. Given the much shorter development history of e-waste recycling and its largely unregulated nature, significant efforts should be made to crack down on illegal e-waste recycling and strengthen pollution control for related activities.

  12. The Western Environmental Technology Office (WETO), Butte, Montana. Technology summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The Western Environmental Technology Office (WETO) is a multi-purpose engineering test facility located in Butte, Montana, and is managed by MSE, Inc. WETO seeks to contribute to environmental research by emphasizing projects to develop heavy metals removal and recovery processes, thermal vitrification systems, and waste minimization/pollution prevention technologies. WETO`s environmental technology research and testing activities focus on the recovery of usable resources from waste. In one of WETO`s areas of focus, groundwater contamination, water from the Berkeley Pit, located near the WETO site, is being used in demonstrations directed toward the recovery of potable water and metal from the heavy metal-bearing water. The Berkeley Pit is part of an inactive copper mine near Butte that was once part of the nation`s largest open-pit mining operation. The Pit contains approximately 25 billion gallons of Berkeley Pit groundwater and surface water containing many dissolved minerals. As part of DOE/OST`s Resource Recovery Project (RRP), technologies are being demonstrated to not only clean the contaminated water but to recover metal values such as copper, zinc, and iron with an estimated gross value of more than $100 million. When recovered, the Berkeley Pit waters could benefit the entire Butte valley with new water resources for fisheries, irrigation, municipal, and industrial use. At WETO, the emphasis is on environmental technology development and commercialization activities, which will focus on mine cleanup, waste treatment, resource recovery, and water resource management.

  13. The Western Environmental Technology Office (WETO), Butte, Montana. Technology summary

    International Nuclear Information System (INIS)

    1996-03-01

    The Western Environmental Technology Office (WETO) is a multi-purpose engineering test facility located in Butte, Montana, and is managed by MSE, Inc. WETO seeks to contribute to environmental research by emphasizing projects to develop heavy metals removal and recovery processes, thermal vitrification systems, and waste minimization/pollution prevention technologies. WETO's environmental technology research and testing activities focus on the recovery of usable resources from waste. In one of WETO's areas of focus, groundwater contamination, water from the Berkeley Pit, located near the WETO site, is being used in demonstrations directed toward the recovery of potable water and metal from the heavy metal-bearing water. The Berkeley Pit is part of an inactive copper mine near Butte that was once part of the nation's largest open-pit mining operation. The Pit contains approximately 25 billion gallons of Berkeley Pit groundwater and surface water containing many dissolved minerals. As part of DOE/OST's Resource Recovery Project (RRP), technologies are being demonstrated to not only clean the contaminated water but to recover metal values such as copper, zinc, and iron with an estimated gross value of more than $100 million. When recovered, the Berkeley Pit waters could benefit the entire Butte valley with new water resources for fisheries, irrigation, municipal, and industrial use. At WETO, the emphasis is on environmental technology development and commercialization activities, which will focus on mine cleanup, waste treatment, resource recovery, and water resource management

  14. Results of detailed ground geophysical surveys for locating and differentiating waste structures in waste management area 'A' at Chalk River Laboratories, Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Tomsons, D.K.; Street, P.J.; Lodha, G.S

    1999-07-01

    Waste Management Area 'A' (WMA 'A'), located in the outer area of the Chalk River Laboratories (CRL) was in use as a waste burial site from 1946 to 1955. Waste management structures include debris-filled trenches, concrete bunkers and miscellaneous contaminated solid materials, and ditches and pits used for liquid dispersal. In order to update historical records, it was proposed to conduct detailed ground geophysical surveys to define the locations of waste management structures in WMA 'A', assist in planning of the drilling and sampling program to provide ground truth for the geophysics investigation and to predict the nature and locations of unknown/undefined shallow structures. A detailed ground geophysical survey grid was established with a total of 127 grid lines, oriented NNE and spaced one metre apart. The geophysical surveys were carried out during August and September, 1996. The combination of geophysical tools used included the Geonics EM61 metal detector, the GSM-19 magnetometer/gradiometer and a RAMAC high frequency ground penetrating radar system. The geophysical surveys were successful in identifying waste management structures and in characterizing to some extent, the composition of the waste. The geophysical surveys are able to determine the presence of most of the known waste management structures, especially in the western and central portions of the grid which contain the majority of the metallic waste. The eastern portion of the grid has a completely different geophysical character. While historical records show that trenches were dug, they are far less evident in the geophysical record. There is clear evidence for a trench running between lines 30E and 63E at 70 m. There are indications from the radar survey of other trench-like structures in the eastern portion. EM61 data clearly show that there is far less metallic debris in the eastern portion. The geophysical surveys were also successful in identifying

  15. New Generation Energy Efficient Refractory Application in Soaking Pits of Bhilai Steel Plant, Sail

    Science.gov (United States)

    Roy, Indranil; Chintaiah, Perumetla; Bhattacharya, Ajoy Kr.; Garai, Swapan Kr.; Ray Choudhury, Pankaj Kr.; Tiwari, Laksman

    In Bhilai Steel Plant (BSP), soaking pits are used for heating ingots for successive rolling into blooms. Pits are operated at a temperature of around 1350°C. Mixed gas (Mixture of Blast Furnace gas & Coke Oven gas) of calorific value around 2040 kcal/Nm3 is used as fuel. The walls of soaking pits were lined with traditional 38% Al2O3 firebricks and top 500mm was cast with 70% Al2O3 low cement castable (LCC). This type of lining results in frequent damages due to hitting by ingots while being lifted from pit by overhead cranes thus affecting the availability of pit. Life of pits was 2 to 2.5 years in BSP with 3-4 cold repairs and 3-4 hot repairs. Energy loss through the wall is also quite high in this type of lining. To triumph over the limitations of the conventional lining, a lining design was developed for the walls which consist of special 70% Al2O3 LCC having high hot strength (HMOR) in combination with specially design flexible SS-304 anchors. Ceramic fiber blanket and insulation bricks were provided between castable and the metallic shell of the pit to minimize the heat loss. A heating schedule was developed and introduced based on available infrastructure at BSP for proper curing of modified LCC based lining. After introduction of modified lining, pit no. 14/2 is running for more than 2.5 years without any repair. To capitalize the success, two more pits i.e. 12/1 and 9/2 were converted to modified lining. These pits are also running satisfactorily for more than 1.5 years. The modification has resulted in higher availability with substantial increase in production. Shell temperature of the modified pits reduced to 90° - 140°C from 120° - 200°C of conventional pits. This shows reduction in heat loss through walls, resulting less fuel consumption and energy saving of about 18%.

  16. Release to the gas phase of metals, S and Cl during combustion of dedicated waste fractions

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; van Lith, Simone Cornelia; Frandsen, Flemming

    2010-01-01

    The release to the gas phase of inorganic elements such as alkali metals. Cl, S, and heavy metals in Waste-to-Energy (WtE) boilers is a challenge. Besides the risk of harmful emissions to the environment, inorganic elements released from the grate may cause severe ash deposition and corrosion...... and the link to the formation of fly ash and aerosols in full-scale waste incinerators. The release of metals, S and Cl from four dedicated waste fractions was quantified as a function of temperature in a lab-scale fixed-bed reactor. The waste fractions comprised chromated copper arsenate (CCA) impregnated....... The lab-scale release results were then compared with results from a related, full-scale partitioning study, in which test runs with the addition of similar, dedicated waste fractions to a base-load waste had been performed in a grate-fired WtE boiler. In general, the elements Al, Ca, Cr, Cu, Fe, Mg, Si...

  17. Application and research of recyclable cables in foundation pit support engineering

    Science.gov (United States)

    Zheng, Suping

    2018-05-01

    Anchoring cables are widely used in the construction of foundation pit as a temporary support structure. After the construction is completed, the anchor cables left in the ground will not only cause environmental pollution but also cause a great waste of resources. The emergence of recyclable cable technology, to avoid such problems, to achieve the secondary use of the anchor cable, excavation in the excavation project is more and more widely used. Combined with the design and construction of recoverable anchor cable in engineering practice, the application effect of recoverable anchor cable in foundation pit support is analyzed, and the conclusion that the support effect of recoverable anchor cable is stable and safe can be obtained Recyclable anchor cable in the future support projects to provide a reference.

  18. Evaluation of heavy metals in the process of composting organic waste of coca leaves

    Directory of Open Access Journals (Sweden)

    Apaza-Condori Emma Eva

    2015-11-01

    Full Text Available The present study is to evaluate the total concentrations of the heavy metals in waste compost samples from coca leaf. This work was carried out Kallutaca Experimental Center, Biofertilizers module Career Agricultural Engineering at the Public University of El Alto, La Paz municipality of Laja. Posed treatments were: T1 (+ Yogurt Coca wastes; T2 (Coca wastes + whey; T3 (Coca wastes + yeast and T4 (Control. The design was completely randomized with 4 treatments and 3 repetitions. The concentration of heavy metals (cadmium, copper, nickel, lead, mercury and chromium; they were categorized into Class A, for the four treatments according to the classifications established by Moreno & Moral (2008.

  19. Application of non-intrusive geophysical techniques at the Mixed Waste Landfill, Technical Area 3, Sandia National Laboratories, New Mexico

    International Nuclear Information System (INIS)

    Peace, J.L.; Goering, T.J.

    1996-03-01

    The Environmental Restoration Project at Sandia National Laboratories, New Mexico is tasked with assessment and remediation of the Mixed Waste Landfill in Technical Area 3. The Mixed Waste Landfill is an inactive radioactive and mixed waste disposal site. The landfill contains disposal pits and trenches of questionable location and dimension. Non-intrusive geophysical techniques were utilized to provide an effective means of determining the location and dimension of suspected waste disposal trenches before Resource Conservation and Recovery Act intrusive assessment activities were initiated. Geophysical instruments selected for this investigation included a Geonics EM-31 ground conductivity meter, the new Geonics EM-61 high precision, time-domain metal detector, and a Geometrics 856 total field magnetometer. The results of these non-intrusive geophysical techniques were evaluated to enhance the efficiency and cost-effectiveness of future waste-site investigations at Environmental Restoration Project sites

  20. Separation of palladium from high-level waste using metal ferro cyanide loaded resins

    International Nuclear Information System (INIS)

    Valsala, T.P.; Joseph, Annie; Yeotikar, R.G.

    2005-01-01

    High-level waste (HLW) is generated during reprocessing of spent fuel. HLW contains corrosion products, unextracted actinides, process chemicals and fission products. A recent trend is there to consider waste as a source of wealth. Among the fission products separation and recovery of platinum group metals have gained great attention. HLW is a good source of palladium of the platinum group metal. The present study shows the feasibility of ion exchange separation of Pd from HLW. (author)

  1. [Correlation of Persistent Free Radicals, PCDD/Fs and Metals in Waste Incineration Fly Ash].

    Science.gov (United States)

    Wang, Tian-jiao; Chen, Tong; Zhan, Ming-xiu; Guo, Ying; Li, Xiao-dong

    2016-03-15

    Environmentally persistent free radicals (EPFRs) are relatively highly stable and found in the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Recent studies have concentrated on model dioxin formation reactions and there are few studies on actual waste incineration fly ash. In order to study EPFRs and the correlation with dioxins and heavy metals in waste incineration fly ash, the spins of EPFRs, concentration of PCDD/Fs and metals in samples from 6 different waste incinerators were detected. The medical waste incineration fly ash from Tianjin, municipal solid waste incineration fly ash from Jiangxi Province, black carbon and slag from municipal solid waste incinerator in Lanxi, Zhejiang Province, all contained EPFRs. Above all the signal in Tianjin sample was the strongest. Hydroxyl radicals, carbon-center radicals and semiquinone radicals were detected. Compared with other samples, Jiangxi fly ash had the highest toxic equivalent quantity (TEQ) of dioxins, up to 7.229 4 ng · g⁻¹. However, the dioxin concentration in the Tianjin sample containing the strongest EPFR signals was only 0.092 8 ng · g⁻¹. There was perhaps little direct numeric link between EPFRs and PCDD/Fs. But the spins of EPFRs in samples presented an increasing trend as the metal contents increased, especially with Al, Fe, Zn. The signal strength of radicals was purposed to be related to the metal contents. The concentration of Zn (0.813 7% ) in the Tianjin sample was the highest and this sample contained much more spins of oxygen-center radicals. We could presume the metal Zn had a greater effect on the formation of EPFRs, and was easier to induce the formation of radicals with a longer half-life period.

  2. Development of radioactive solid waste retrieving and conditioning technology in CIAE

    International Nuclear Information System (INIS)

    Li Meishan

    2005-01-01

    For the past 50 years, more than 40,000 m 3 LILW were generated during defense production and research in china. Most of the waste are still storing in pit-type storage facilities, which were designed by the former Soviet Russia in China. Up to now the project on solid waste retrieving and conditioning hasn't been carried out in China. At the beginning of the last century 90s 'R and D of retrieving, sorting, and compaction technologies of LILW' had been done in CIAE. In 2002, the authorities ratified the project about LILW retrieving from the pit-type storage facilities and conditioning by super-compaction. It is the first time to retrieve the solid waste from pit-type storage facilities in China. What's more, almost there are no similar projects in the world. The project consists of three parts: waste retrieving unit, waste pre-treating unit and conditioning unit, which is super-compaction workshop. It will set a good example for other similar facilities in the Nuclear Energy Industry after the project will have been completed successfully. (authors)

  3. NELL-1 increases pre-osteoblast mineralization using both phosphate transporter Pit1 and Pit2

    Energy Technology Data Exchange (ETDEWEB)

    Cowan, Catherine M. [Department of Bioengineering, University of California, Los Angeles, 420 Westwood Plaza,7523 Boelter Hall, Los Angeles, CA 90095 (United States); Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, University of California, Los Angeles, 40833 Le Conte Ave, Los Angeles, CA 90095 (United States); Zhang, Xinli; James, Aaron W.; Mari Kim, T.; Sun, Nichole [Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, University of California, Los Angeles, 40833 Le Conte Ave, Los Angeles, CA 90095 (United States); Wu, Benjamin [Department of Bioengineering, University of California, Los Angeles, 420 Westwood Plaza,7523 Boelter Hall, Los Angeles, CA 90095 (United States); Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, University of California, Los Angeles, 40833 Le Conte Ave, Los Angeles, CA 90095 (United States); Ting, Kang [Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, University of California, Los Angeles, 40833 Le Conte Ave, Los Angeles, CA 90095 (United States); Soo, Chia, E-mail: bsoo@ucla.edu [UCLA and Orthopaedic Hospital Department of Orthopaedic Surgery and the Orthopaedic, Hospital Research Center, University of California, Los Angeles, 2641 Charles E. Young Dr. South, Los Angeles, CA 90095 (United States)

    2012-06-08

    Highlights: Black-Right-Pointing-Pointer NELL-1 accelerates extracellular matrix mineralization in MC3T3-E1 pre-osteoblasts. Black-Right-Pointing-Pointer NELL-1 significantly increases intracellular inorganic phosphate levels. Black-Right-Pointing-Pointer NELL-1 positively regulates osteogenesis but not proliferation in MC3T3-E1 cells. Black-Right-Pointing-Pointer NELL-1 regulates inorganic phosphate transporter activity. -- Abstract: NELL-1 is a potent osteoinductive molecule that enhances bone formation in multiple animal models through currently unidentified pathways. In the present manuscript, we hypothesized that NELL-1 may regulate osteogenic differentiation accompanied by alteration of inorganic phosphate (Pi) entry into the osteoblast via sodium dependent phosphate (NaPi) transporters. To determine this, MC3T3-E1 pre-osteoblasts were cultured in the presence of recombinant human (rh)NELL-1 or rhBMP-2. Analysis was performed for intracellular Pi levels through malachite green staining, Pit-1 and Pit-2 expression, and forced upregulation of Pit-1 and Pit-2. Results showed rhNELL-1 to increase MC3T3-E1 matrix mineralization and Pi influx associated with activation of both Pit-1 and Pit-2 channels, with significantly increased Pit-2 production. In contrast, Pi transport elicited by rhBMP-2 showed to be associated with increased Pit-1 production only. Next, neutralizing antibodies against Pit-1 and Pit-2 completely abrogated the Pi influx effect of rhNELL-1, suggesting rhNELL-1 is dependent on both transporters. These results identify one potential mechanism of action for rhNELL-1 induced osteogenesis and highlight a fundamental difference between NELL-1 and BMP-2 signaling.

  4. NELL-1 increases pre-osteoblast mineralization using both phosphate transporter Pit1 and Pit2

    International Nuclear Information System (INIS)

    Cowan, Catherine M.; Zhang, Xinli; James, Aaron W.; Mari Kim, T.; Sun, Nichole; Wu, Benjamin; Ting, Kang; Soo, Chia

    2012-01-01

    Highlights: ► NELL-1 accelerates extracellular matrix mineralization in MC3T3-E1 pre-osteoblasts. ► NELL-1 significantly increases intracellular inorganic phosphate levels. ► NELL-1 positively regulates osteogenesis but not proliferation in MC3T3-E1 cells. ► NELL-1 regulates inorganic phosphate transporter activity. -- Abstract: NELL-1 is a potent osteoinductive molecule that enhances bone formation in multiple animal models through currently unidentified pathways. In the present manuscript, we hypothesized that NELL-1 may regulate osteogenic differentiation accompanied by alteration of inorganic phosphate (Pi) entry into the osteoblast via sodium dependent phosphate (NaPi) transporters. To determine this, MC3T3-E1 pre-osteoblasts were cultured in the presence of recombinant human (rh)NELL-1 or rhBMP-2. Analysis was performed for intracellular Pi levels through malachite green staining, Pit-1 and Pit-2 expression, and forced upregulation of Pit-1 and Pit-2. Results showed rhNELL-1 to increase MC3T3-E1 matrix mineralization and Pi influx associated with activation of both Pit-1 and Pit-2 channels, with significantly increased Pit-2 production. In contrast, Pi transport elicited by rhBMP-2 showed to be associated with increased Pit-1 production only. Next, neutralizing antibodies against Pit-1 and Pit-2 completely abrogated the Pi influx effect of rhNELL-1, suggesting rhNELL-1 is dependent on both transporters. These results identify one potential mechanism of action for rhNELL-1 induced osteogenesis and highlight a fundamental difference between NELL-1 and BMP-2 signaling.

  5. The use of sugar and alcohol industry waste in the adsorption of potentially toxic metals.

    Science.gov (United States)

    Santos, Oseas Silva; Mendonça, André Gustavo Ribeiro; Santos, Josué Carinhanha Caldas; Silva, Amanda Paulina Bezerra; Costa, Silvanio Silverio Lopes; Oliveira, Luciana Camargo; Carmo, Janaina Braga; Botero, Wander Gustavo

    2016-01-01

    One of the waste products of the industrial process of the sugar and alcohol agribusiness is filter cake (FC). This waste product has high levels of organic matter, mainly proteins and lipids, and is rich in calcium, nitrogen, potassium and phosphorous. In this work we characterized samples of FC from sugar and alcohol industries located in sugarcane-producing regions in Brazil and assessed the adsorption of potentially toxic metals (Cu(II), Cd(II), Pb(II), Ni(II) and Cr(III)) by this waste in mono- and multi-elemental systems, seeking to use FC as an adsorbent in contaminated environments. The characterization of FCs showed significant differences between the samples and the adsorption studies showed retention of over 90% of potentially toxic metals. In a competitive environment (multi-metallic solution), the FC was effective in adsorbing all metals except lead, but less effective compared to the mono-metallic solution. These results show the potential for use of this residue as an adsorbent in contaminated environments.

  6. Different Heavy Metal Accumulation Strategies of Epilithic Lichens Colonising Artificial Post-Smelting Wastes.

    Science.gov (United States)

    Rola, Kaja; Osyczka, Piotr; Kafel, Alina

    2016-02-01

    Lichens appear to be essential and effective colonisers of bare substrates including the extremely contaminated wastes of slag dumps. This study examines the metal accumulation capacity of epilithic lichens growing directly on the surface of artificial slag sinters. Four species representing different growth forms, i.e., crustose Candelariella aurella, Lecanora muralis, and Lecidea fuscoatra and fruticose Stereocaulon nanodes, were selected to evaluate the relationships between zinc, lead, cadmium, and nickel contents in their thalli and host substrates. Bioaccumulation factors of examined crustose lichens showed their propensity to hyperaccumulate heavy metals. Contrarily, concentrations of metals in fruticose thalli of S. nanodes were, as a rule, lower than in the corresponding substrates. This indicates that the growth form of thalli and degree of thallus adhesion to the substrate has a significant impact on metal concentrations in lichens colonising post-smelting wastes. Nonlinear regression models described by power functions show that at greater levels of Pb concentration in the substrate, the ability of C. aurella, L. muralis and L. fuscoatra to accumulate the metal experiences a relative decrease, whereas hyperbolic function describes a similar trend in relation to Ni content in S. nanodes. This phenomenon may be an important attribute of lichens that facilitates their colonisation of the surface of slag wastes.

  7. Directions of development of research methods in the assessment of leaching of heavy metals from mineral waste

    Directory of Open Access Journals (Sweden)

    Król Anna

    2016-01-01

    Full Text Available There are many test methods to assess the level of the release of heavy metals into the environment from mineral waste materials. Leaching methods can be different depending on the leaching time periods, leaching dynamics, sample preparation method or the pH of the elution medium. In Poland, little attention is paid to the research on the relationship between the leaching of particular heavy metals from mineral wastes and changes in environmental conditions, including the pH of the environment. Tests being carried out abroad have started to pay great attention to the pH-dependent impact of the environment and the liquid being in contact with the material on the degree of leaching contaminants from wastes. The solubility of all metals depends on the value of the pH. Authors of the paper will try to prove that Polish methods of waste characterization is incomplete and inconsistent with opinions prevailing in the global literature. The procedure described in the Polish standards are insufficient to determine the actual level of leaching of heavy metals having regard to the impact of multiple external conditions on the level of leaching of heavy metals. Paper will present a directions of development of research methods in the assessment of leaching of heavy metals from mineral waste.

  8. Interacting Effects Induced by Two Neighboring Pits Considering Relative Position Parameters and Pit Depth

    Directory of Open Access Journals (Sweden)

    Yongfang Huang

    2017-04-01

    Full Text Available For pre-corroded aluminum alloy 7075-T6, the interacting effects of two neighboring pits on the stress concentration are comprehensively analyzed by considering various relative position parameters (inclination angle θ and dimensionless spacing parameter λ and pit depth (d with the finite element method. According to the severity of the stress concentration, the critical corrosion regions, bearing high susceptibility to fatigue damage, are determined for intersecting and adjacent pits, respectively. A straightforward approach is accordingly proposed to conservatively estimate the combined stress concentration factor induced by two neighboring pits, and a concrete application example is presented. It is found that for intersecting pits, the normalized stress concentration factor Ktnor increases with the increase of θ and λ and always reaches its maximum at θ = 90°, yet for adjacent pits, Ktnor decreases with the increase of λ and the maximum value appears at a slight asymmetric location. The simulations reveal that Ktnor follows a linear and an exponential relationship with the dimensionless depth parameter Rd for intersecting and adjacent cases, respectively.

  9. Toxic metals in WEEE: Characterization and substance flow analysis in waste treatment processes

    Energy Technology Data Exchange (ETDEWEB)

    Oguchi, Masahiro, E-mail: oguchi.masahiro@nies.go.jp; Sakanakura, Hirofumi; Terazono, Atsushi

    2013-10-01

    Waste electrical and electronic equipment (WEEE) has received extensive attention as a secondary source of metals. Because WEEE also contains toxic substances such as heavy metals, appropriate management of these substances is important in the recycling and treatment of WEEE. As a basis for discussion toward better management of WEEE, this study characterizes various types of WEEE in terms of toxic metal contents. The fate of various metals contained in WEEE, including toxic metals, was also investigated in actual waste treatment processes. Cathode-ray tube televisions showed the highest concentration and the largest total amount of toxic metals such as Ba, Pb, and Sb, so appropriate recycling and disposal of these televisions would greatly contribute to better management of toxic metals in WEEE. A future challenge is the management of toxic metals in mid-sized items such as audio/visual and ICT equipment because even though the concentrations were not high in these items, the total amount of toxic metals contained in them is not negligible. In the case of Japan, such mid-sized WEEE items as well as small electronic items are subject to municipal solid waste treatment. A case study showed that a landfill was the main destination of toxic metals contained in those items in the current treatment systems. The case study also showed that changes in the flows of toxic metals will occur when treatment processes are modified to emphasize resource recovery. Because the flow changes might lead to an increase in the amount of toxic metals released to the environment, the flows of toxic metals and the materials targeted for resource recovery should be considered simultaneously. - Highlights: ► Appropriate management of toxic metals contained in WEEE is important during recycling and treatment of WEEE. ► CRT TVs contain large amount of toxic metals with high concentration and thus appropriate management is highly important. ► Mid-sized equipment is a future target for

  10. Waste inventory, waste characteristics and waste repositories in Japan

    International Nuclear Information System (INIS)

    Shimooka, K.

    1997-01-01

    There are two types of repositories for the low level radioactive wastes in Japan. One is a trench type repository only for concrete debris generated from the dismantling of the research reactor. According to the safety assurance system, Japan Atomic Energy Research Institute (JAERI) has disposed of the concrete debris arose from the dismantling of the Japan Power Demonstration Reactor (JPDR). The other type is the concreted pit with engineered barriers. Rokkasho Low Level Radioactive Waste Disposal Center has this type of repository mainly for the power plant wastes. Japan Nuclear Fuel Ltd. (JNFL) established by electric power companies is the operator of the LLW disposal project. JNFL began the storage operation in 1992 and buried approximately 60,000 drums there. Two hundred thousand drums of uniformly solidified, waste may be buried ultimately. 4 refs, 3 tabs

  11. Metals and polybrominated diphenyl ethers leaching from electronic waste in simulated landfills

    Energy Technology Data Exchange (ETDEWEB)

    Kiddee, Peeranart [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, Adelaide, 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Mawson Lakes Campus, Adelaide, 5095 (Australia); Naidu, Ravi, E-mail: ravi.naidu@crccare.com [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, Adelaide, 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Mawson Lakes Campus, Adelaide, 5095 (Australia); Wong, Ming H. [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong (China)

    2013-05-15

    Highlights: • Simulated landfill columns provided realistic results than lab based column study. • Column leachates showed significant seasonal effect on toxic substances. • Toxic substances in the landfill leachates pose environmental and health hazards. • A better management of e-waste is urgently needed. -- Abstract: Landfills established prior to the recognition of potential impacts from the leaching of heavy metals and toxic organic compounds often lack appropriate barriers and pose significant risks of contamination of groundwater. In this study, bioavailable metal(oids) and polybrominated diphenyl ethers (PBDEs) in leachates from landfill columns that contained intact or broken e-waste were studied under conditions that simulate landfills in terms of waste components and methods of disposal of e-wastes, and with realistic rainfall. Fourteen elements and PBDEs were analysed in leachates over a period of 21 months. The results demonstrate that the average concentrations of Al, Ba, Be, Cd, Co, Cr, Cu, Ni, Pb, Sb and V in leachates from the column that contained broken e-waste items were significantly higher than the column without e-waste. BDE-153 was the highest average PBDEs congener in all columns but the average of ∑PBDEs levels in columns that contained intact e-waste were (3.7 ng/l) and were not significantly higher than that in the leachates from the control column.

  12. A New Method for Haul Road Design in Open-Pit Mines to Support Efficient Truck Haulage Operations

    Directory of Open Access Journals (Sweden)

    Jieun Baek

    2017-07-01

    Full Text Available The design of a haul road for an open-pit mine can significantly affect the cost associated with hauling ore and waste to the surface. This study proposes a new method for haul road design in open-pit mines to support efficient truck haulage operations. The road layout in open-pit mines was optimized by using raster-based least-cost path analysis, and the resulting zigzag road sections were simplified by applying the Douglas-Peucker algorithm. In addition, the road layout was modified by reflecting the radius of curvature suggested in the road design guides. Finally, a three-dimensional model reflecting the results of the road design was created by combining the road layout modification result with the slope of the open-pit mine and the bench design result. The application of the proposed method to an area containing gold deposits made it possible to design a haul road for open-pit mines such that it supported efficient truck haulage operations; furthermore, the time required for truck movement along the road could be estimated. The proposed method is expected to be useful for planning and designing open-pit mines and to facilitate the improvement of the road design function of existing mining software applications.

  13. Factors affecting medical waste management in lowlevel health ...

    African Journals Online (AJOL)

    African Journal of Environmental Science and Technology ... evaluation of medical waste management systems was conducted in the low-level health ... In Ilala, 70% of the health facilities burn wastes in poorly designed incinerators, open pit ...

  14. Outline of a method for final storage of low- and medium-active waste from possible Danish power reactors

    International Nuclear Information System (INIS)

    Brodersen, K.; Jensen, J.; Oestergaard, K.

    1977-02-01

    A method is outlined for the final storage of Danish low-and medium-active power reactor waste. The waste drums are contained in large concretre blocks placed just below the ground surface. A plant for storing waste by means of this method is sketched. It consists of a system of reinforced concrete pits with the top level with the ground surface. Each pit measures c. 5 x 5 m and is c. 6 m deep. The pits are envisaged cast with a permanent inside, step-like shuttering of thin steel plates. The volume between the drums will be cast with concrete when a pit is filled. Calculations are given of the construction and running costs. It is estimated that the final storage of reactor wastes is only a small problem regarding economy and space, and also that there is hardly doubt that full safety can be achieved. (B.P.)

  15. Waste Derived Sorbents and Their Potential Roles in Heavy Metal Remediation Applications

    Directory of Open Access Journals (Sweden)

    Chiang Y. W.

    2013-04-01

    Full Text Available Inorganic waste materials that have the suitable inherent characteristics could be used as precursors for the synthesis of micro- and mesoporous materials, which present great potential to be re-utilized as sorbent materials for heavy metal remediation. Three inorganic waste materials were studied in the present work: water treatment residuals (WTRs from an integrated drinking water/wastewater treatment plant, and fly ash and bottom ash samples from a municipal solid waste incinerator (MSWI. These wastes were converted into three sorbent materials: ferrihydrite-like materials derived from drying of WTRs, hydroxyapatite-like material derived from ultrasound assisted synthesis of MSWI fly ash with phosphoric acid solution, and a zeolitic material derived from alkaline hydrothermal conversion of MSWI bottom ash. The performance of these materials, as well as their equivalent commercially available counterparts, was assessed for the adsorption of multiple heavy metals (As, Cd, Co, Ni, Pb, Zn from synthetic solutions, contaminated sediments and surface waters; and satisfactory results were obtained. In addition, it was observed that the combination of sorbents into sorbent mixtures enhanced the performance levels and, where applicable, stabilized inherently mobile contaminants from the waste derived sorbents.

  16. Slag-based materials for toxic metal and radioactive waste stabilization

    International Nuclear Information System (INIS)

    Langton, C.A.

    1989-01-01

    This paper discusses a salt solution that is a hazardous waste and has both corrosive and metal toxicity characteristics. Objectives of a wasteform designed to stabilize this solution are presented. Disposal site characterization studies are examined

  17. High-sensitive detection by direct interrogation of 14 MeV Acc neutrons, (1). Uranium-contained metal matrix in a waste dram

    International Nuclear Information System (INIS)

    Haruyama, Mitsuo; Takase, Misao; Tobita, Hiroshi; Mori, Takamasa

    2004-01-01

    Previously, authors reported that the 14 MeV-neutron direct interrogation method has made possible measure for the discrimination of clearance levels of concrete solidification uranium waste. In this paper, applicability of the method to metal waste matrix is discussed based on the results of simulation experiments by the continuation energy Monte Carlo calculation code (MVP). The problem is that self-neutron moderation effect in a waste cannot be expected when a waste matrix is metal. To solve this, a moderator is adopted so as to surround a metal waste drum and to slow down suitably a 14 MeV neutrons. The simulation calculation showed that this effect is satisfactorily large. The detection limit of radioactivity concentration to 4.5% enriched uranium has been found to be 0.0973 Bq/g in the metal waste model of 215.59 kg gross weight, in which 61 pipes are stuffed into its drum. Moreover, the position-dependent sensitivity difference in a metal waste drum can be settled as small as to ±13.5%. In conclusion, it can be said that 14 MeV-neutron direct interrogation method can be applied to the waste of a metal system: the detection sensitivity is high enough and the position-dependent sensitivity difference is small admittedly. Hence the method can be applied also to discrimination measurement of the clearance level of metal uranium waste. (author)

  18. Multiple plasmonically induced transparency for chip-scale bandpass filters in metallic nanowaveguides

    Science.gov (United States)

    Lu, Hua; Yue, Zengqi; Zhao, Jianlin

    2018-05-01

    We propose and investigate a new kind of bandpass filters based on the plasmonically induced transparency (PIT) effect in a special metal-insulator-metal (MIM) waveguide system. The finite element method (FEM) simulations illustrate that the obvious PIT response can be generated in the metallic nanostructure with the stub and coupled cavities. The lineshape and position of the PIT peak are particularly dependent on the lengths of the stub and coupled cavities, the waveguide width, as well as the coupling distance between the stub and coupled cavities. The numerical simulations are in accordance with the results obtained by the temporal coupled-mode theory. The multi-peak PIT effect can be achieved by integrating multiple coupled cavities into the plasmonic waveguide. This PIT response contributes to the flexible realization of chip-scale multi-channel bandpass filters, which could find crucial applications in highly integrated optical circuits for signal processing.

  19. Heavy metal contamination of soil and water in the vicinity of an abandoned e-waste recycling site: implications for dissemination of heavy metals.

    Science.gov (United States)

    Wu, Qihang; Leung, Jonathan Y S; Geng, Xinhua; Chen, Shejun; Huang, Xuexia; Li, Haiyan; Huang, Zhuying; Zhu, Libin; Chen, Jiahao; Lu, Yayin

    2015-02-15

    Illegal e-waste recycling activity has caused heavy metal pollution in many developing countries, including China. In recent years, the Chinese government has strengthened enforcement to impede such activity; however, the heavy metals remaining in the abandoned e-waste recycling site can still pose ecological risk. The present study aimed to investigate the concentrations of heavy metals in soil and water in the vicinity of an abandoned e-waste recycling site in Longtang, South China. Results showed that the surface soil of the former burning and acid-leaching sites was still heavily contaminated with Cd (>0.39 mg kg(-1)) and Cu (>1981 mg kg(-1)), which exceeded their respective guideline levels. The concentration of heavy metals generally decreased with depth in both burning site and paddy field, which is related to the elevated pH and reduced TOM along the depth gradient. The pond water was seriously acidified and contaminated with heavy metals, while the well water was slightly contaminated since heavy metals were mostly retained in the surface soil. The use of pond water for irrigation resulted in considerable heavy metal contamination in the paddy soil. Compared with previous studies, the reduced heavy metal concentrations in the surface soil imply that heavy metals were transported to the other areas, such as pond. Therefore, immediate remediation of the contaminated soil and water is necessary to prevent dissemination of heavy metals and potential ecological disaster. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. 40 CFR 60.33b - Emission guidelines for municipal waste combustor metals, acid gases, organics, and nitrogen oxides.

    Science.gov (United States)

    2010-07-01

    ... combustor metals, acid gases, organics, and nitrogen oxides. 60.33b Section 60.33b Protection of Environment... Constructed on or Before September 20, 1994 § 60.33b Emission guidelines for municipal waste combustor metals, acid gases, organics, and nitrogen oxides. (a) The emission limits for municipal waste combustor metals...

  1. Application of a cross-pit bridge conveyor system in mining

    Energy Technology Data Exchange (ETDEWEB)

    Zeindler, R.W. (Krupp Canada Inc., Calgary, Alberta); Fawcett, D.A.

    1981-04-01

    A summary is presented of the report completed by the Coal Mining Research Centre in 1980. This report was of a cross-pit conveyor system applied as an auxillary mining complement to the major stripping unit, a dragline. The purpose of the CMRC report was to evaluate selective mining and replacement of the upper horizons of the strata as an aid in reclamation. These strata were the topsoil, subsoil and glacial till. Past utilization of cross-pit conveyor systems and related engineering studies were assessed. The parameters of the study were based on the mining and geological conditions of the Alberta prairie coal mines. The principal excavator for stripping was a dragline. Excavation of the upper horizons was done by a bucket-wheel excavator discharging onto the cross-pit conveyor. Alternative equipment applications were economically compared. Four cases or geological sections were evaluated in detail. The economics of the alternative mining systems for each of the cases were determined. In all instances, the most economical solution was a tandem system utilizing a dragline with a bucket-wheel excavator/cross-pit conveyor system. For both the CMRC study and a similar US paper, the application of a tandem system provided the lowest annual ownership and operating costs. The tandem system consists of a dragline excavating and casting the majority of the waste or overburden and a BWE/CPCS selectively excavating and replacing the topsoil, subsoil and part of the unconsolidated overburden. The bridge spans and designs are within known technical and economic limits.

  2. Corrosion of metal containers containing cemented radioactive wastes

    International Nuclear Information System (INIS)

    Duffo, G.S.; Farina, S.B.; Schulz, F.M.; Marotta, F

    2010-01-01

    Nuclear activities generate different kinds of radioactive wastes. In the case of Argentina, wastes classified as low and medium level are conditioned in metal drums for final disposal in a repository whose design is based on the use of multiple and independent barriers. Nuclear energy plants generate a large volume of mid-level radioactive wastes, consisting mainly of ion-exchange resins contaminated by fission products. Other contaminated products such as gloves, papers, clothing, rubber and plastic tubing, can be incinerated and the ashes from the combustion also constitute wastes that must be disposed of. These wastes (resins and ashes) must be immobilized in order to avoid the release of radionuclides into the environment. The wastes usually undergo a process of cementing to immobilize them. This work aims to systematically study the process of degradation by corrosion of the steel drums in contact with the cemented resins and with the ashes cemented with the addition of different types and concentrations of aggressive compounds (chloride and sulfate). The specimens are configured so that the parameters of interest for the steel in contact with the cemented materials can be measured. The variables of corrosion potential, electric resistivity of the matrix and polarization resistance (PR) were monitored and show that the presence of chloride increases the susceptibility to corrosion of the drum steel that is in contact with the cement resin matrix

  3. Perovskite-Ni composite: a potential route for management of radioactive metallic waste.

    Science.gov (United States)

    Mahadik, Pooja Sawant; Sengupta, Pranesh; Halder, Rumu; Abraham, G; Dey, G K

    2015-04-28

    Management of nickel - based radioactive metallic wastes is a difficult issue. To arrest the release of hazardous material to the environment it is proposed to develop perovskite coating for the metallic wastes. Polycrystalline BaCe0.8Y0.2O3-δ perovskite with orthorhombic structure has been synthesized by sol-gel route. Crystallographic analyses show, the perovskite belong to orthorhombic Pmcn space group at room temperature, and gets converted to orthorhombic Incn space group at 623K, cubic Pm3m space group (with a=4.434Å) at 1173K and again orthorhombic Pmcn space group at room temperature after cooling. Similar observations have been made from micro-Raman study as well. Microstructural studies of BaCe0.8Y0.2O3-δ-NiO/Ni composites showed absence of any reaction product at the interface. This suggests that both the components (i.e. perovskite and NiO/Ni) of the composite are compatible to each other. Interaction of BaCe0.8Y0.2O3-δ-NiO/Ni composites with simulated barium borosilicate waste glass melt also did not reveal any reaction product at the interfaces. Importantly, uranium from the waste glass melt was found to be partitioned within BaCe0.8Y0.2O3-δ perovskite structure. It is therefore concluded that BaCe0.8Y0.2O3-δ can be considered as a good coating material for management of radioactive Ni based metallic wastes. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. A Study on Microstructure Change and Pitting Corrosion Resistance of Ferritic Stainless Steel Weldment According to Nb Contents

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong-Min; Shin, Yong-Taek; Lee, Sang-Hwa; Lee, Jun-Hee; Lee, Hae-Woo [Dong-A University, Busan (Korea, Republic of); Lee, Sung-Riong [Kangwon National University, ChunCheon (Korea, Republic of); Kim, Soon-Ho [Silla University, Busan (Korea, Republic of)

    2014-01-15

    This paper identified the effects of Nb on microstructure. Also, it has studied on uniform and pitting corrosion resistance in a ferritic stainless steel weld metal of the automobile exhaust system. We fabricated 3 flux cored wires designed with 0-1.0 wt% Nb and performed Flux Cored Arc Welding. We observed the microstructure with the SEM/EDS and EBSD. To evaluate the uniform and pitting corrosion resistance, we performed a potentiodynamic polarization test in 0.2 M H{sub 2}SO{sub 4} and 0.1, 0.3, 0.5 M NaCl. As a result of the tests, we found that as the amount of addition of Nb rose, the amount of Cr-carbide fell. The microstructure became more refined. The specimen with 1.0%Nb added had the highest uniform and pitting corrosion resistance. After the pitting corrosion test, a pit was formed at the grain boundary that has no addition of Nb. In addition, in the specimen with added Nb, pits were formed at the inclusions.

  5. X-ray diffraction of the diminution in the concentration of heavy metals from industrial waste water sludge

    International Nuclear Information System (INIS)

    Carreno de Leon, M.C.

    1996-01-01

    We worked with an apparatus and process patented for Jaime Vite Torres, in the United States of America, for extracting simultaneously toxic and value metals from foundry sands. In this research, we used similar devices to remove toxic metals of waste water sludge. Generation of solid wastes including dangerous in 1992 in Mexico were 450,000 ton/day in accordance with the National Institut of Ecology (INE-SEDESOL 1992). With the apparatus and process of the present work we obtained two important points, whic are: a) the recovery of metals in solution which can be recycled and, b) an important reduction in the toxic of the wastes which one treated can be handled as normal waste with important savings. From among the metals which it is possible to recover one can mention among others: Au, Pt, Ag, Cr, Mn, Co, Pb, Al, Ni and others. (Author)

  6. Influence of microstructure and elemental partitioning on pitting corrosion resistance of duplex stainless steel welding joints

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhiqiang; Jing, Hongyang [School of Materials Science and Engineering, Tianjin University, Tianjin 300350 (China); Tianjin Key Laboratory of Advanced Joining Technology, Tianjin 300350 (China); Xu, Lianyong, E-mail: xulianyong@tju.edu.cn [School of Materials Science and Engineering, Tianjin University, Tianjin 300350 (China); Tianjin Key Laboratory of Advanced Joining Technology, Tianjin 300350 (China); Han, Yongdian; Zhao, Lei [School of Materials Science and Engineering, Tianjin University, Tianjin 300350 (China); Tianjin Key Laboratory of Advanced Joining Technology, Tianjin 300350 (China); Zhang, Jianli [Welding laboratory, Offshore Oil Engineering (Qing Dao) Company, Qing Dao 266520 (China)

    2017-02-01

    Highlights: • N{sub 2}-supplemented shielding gas promoted nitrogen solid-solution in the austenite. • Secondary austenite had higher Ni but lower Cr and Mo than primary austenite. • Pitting corrosion preferentially occurred at secondary austenite and Cr{sub 2}N. • Adding N{sub 2} in shielding gas improved pitting corrosion resistance of GTAW joint. • E2209T{sub 1} weld metal had very poor pitting corrosion resistance due to inclusions. - Abstract: The influences of microstructure and elemental partitioning on pitting corrosion resistance of duplex stainless steel joints welded by gas tungsten arc welding (GTAW) and flux-cored arc welding (FCAW) with different shielding gas compositions were studied by optical microscopy, electron backscatter diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, electron probe microanalysis, and potentiostatic and potentiodynamic polarization methods The adding 2% N{sub 2} in shielding gas facilitated primary austenite formation in GTAW weld metal (WM) and suppressed Cr{sub 2}N precipitation in GTAW weld root. In the HAZ, the banded microstructure disappeared while the coarse ferrite grains maintained same orientation as the banded ferrite in the BM. In the WM, the ferrite had one single orientation throughout a grain, whereas several families of austenite appeared. The austenite both in BM and WM enriched in Ni and nitrogen, while Cr and Mo were concentrated in the ferrite and thus no element showed clear dendritic distribution in the WM (ER2209 and E2209T{sub 1}). In addition, the secondary austenite had higher Ni content but lower Cr and Mo content than the primary austenite. The N{sub 2}-supplemented shielding gas promoted nitrogen solid-solution in the primary and secondary austenite. Furthermore, the secondary austenite had relatively lower pitting resistance equivalent number (PREN) than the ferrite and primary austenite, thereby resulting in its preferential

  7. Embedding of solid high-level wastes into metal and non-metal matrices

    International Nuclear Information System (INIS)

    Geel, J. van; Eschrich, H.; Dobbels, F.; Favre, P.; Sterner, H.

    1980-03-01

    The primary objective of embedding solidification high-level waste forms of high specific activity into a matrix material is to obtain final waste composites with moderate inner temperatures, even at large waste loadings per meter cylinder length. Secondary objectives are to produce a non-porous, crack-free composite product with a durability superior to that of the embedded waste form itself. The temperature distribution in composite material composed of vitreous beads embedded into a metal matrix (vitromets) are compared with that in a vitreous block, of equal heat generation per meter height, during short- and long-term storage. It was found that for storage under water, inner temperatures below 100 0 C are assured in vitromets, produced from short-cooled high-level wastes, and containing high waste loadings per metercanister height. The chemical and mechanical stability, as well as the thermal conductivity have been examined for vitromets containing various matrix materials whereby emphasis is imparted to lead- and aluminum alloys. The corrosion of lead- and aluminum alloys in distilled water, brine solution and dry salt has been examined at temperatures up to 230 0 C and pressures up to 3.5 MPa. Some lead alloys were found to exhibit superior corrosion resistance in these chemical environments than certain reference borosilicate glasses. The deformation behavior of vitromets under axial compression has been investigated at different temperatures and varying height diameter ratios. The maturity of the vitromet production is finally demonstrated by presenting process data from hot-laboratory scale and cold semi-industrial scale production units. (author)

  8. Thermochemical treatment of radioactive waste by using powder metal fuels

    International Nuclear Information System (INIS)

    Dmitriev, S.A.; Ojovan, M.I.; Karlina, O.K.

    2001-01-01

    Full text: A thermochemical approach was suggested for treating and conditioning specific streams of radioactive wastes for example spent ion exchange resins, mixed, organic or chlorine-containing radioactive waste as well as in order to decontaminate heavily contaminated surfaces. Conventional treatment methods of such waste encounters serious problems concerning complete destruction of organic molecules and possible emissions of radionuclides, heavy metals and chemically hazardous species or in case of contaminated materials - complete removal of contamination from surface. The thermochemical treatment of radioactive waste uses powdered metal fuels (PMF) that are specifically formulated for the waste composition and react chemically with the waste components. Thermochemical treatment technologies use the energy of chemical reactions in the mixture of waste with PMF to sustain both decomposition and synthesis processes as well as processes of isomorphic substitutions of hazardous elements into stable mineral forms. The composition of the PMF is designed in such a way as to minimise the release of hazardous components and radionuclides in the off gas and to confine the contaminants in the mineral or glass like final products. The thermochemical procedures allow decomposition of organic matter and capturing hazardous radionuclides and chemical species simultaneously. Thermochemical treatment technologies are very efficient, easy to apply, they have low capital investment and can be used both at large and small facilities. An advantage of thermochemical technologies is their autonomy. Thus these technologies can be successfully applied in order to treat small amount of waste without usage of complex and expensive equipment. They can be used also in emergency situations. Currently the thermochemical treatment technologies were developed and demonstrated to be feasible as follows: 1. Decontamination of surfaces; 2. Processing of organic waste; 3. Vitrification of dusty

  9. The role of nitrogen in improving pitting corrosion resistance of high-alloy austenitic and duplex stainless steel welds

    International Nuclear Information System (INIS)

    Vilpas, M.; Haenninen, H.

    1999-01-01

    The effects of nitrogen alloyed shielding gas on weld nitrogen content and pitting corrosion resistance of super austenitic (6%Mo) and super duplex stainless steels have been studied with special emphasis on microsegregation behaviour of Cr, Mo and N. The measurements performed with the 6%Mo steel indicate that all these elements segregate interdendritically in the fully austenitic weld metal. With nitrogen addition to the shielding gas the enrichment of nitrogen to the interdendritic regions is more pronounced than to the dendrite cores due to which the pitting corrosion resistance of the dendrite cores increases only marginally. In the super duplex steel welds nitrogen enriches in austenite increasing its pitting corrosion resistance more effectively. In these welds the pitting corrosion resistance of the ferrite phase remains lower. (orig.)

  10. 218-E-8 Borrow Pit Demolition Site closure plan. Revision 1

    International Nuclear Information System (INIS)

    Ruck, F.R.

    1994-01-01

    The 218-E-8 Demolition Site was the site of a single demolition event in November of 1984. This demolition event was a form of thermal treatment for discarded explosive chemical products. Because the 218-E-8 Demolition Site will no longer be used for this thermal activity, the site will be closed. Closure will be conducted pursuant to the requirements of the Washington State Department of Ecology (Ecology) ''Dangerous Waste Regulations,'' Washington Administrative Code (WAC) 173-303-610 and 40 Code of Federal Regulations (CFR) 270.1. The 218-E-8 Borrow Pit Demolition Site Closure Plan consists of a Hanford Facility Dangerous Waste Part A Permit Application, Form 3, Revision 4, and a closure plan. An explanation of the Part A Form 3, submitted with this closure plan is provided at the beginning of the Part A Section. The closure plan consists of nine chapters and five appendices. This closure plan presents a description of the 218-E-8 Demolition Site, the history of the waste treated, and the approach that will be followed to close the 218-E-8 Demolition Site. Because there were no radioactively contaminated chemicals involved in t he demolitions at the 218-E-8 Borrow Pit site, the information on radionuclides is provided for ''information only.'' Remediation of any radioactive contamination is not within the scope of this closure plan. Only dangerous constituents derived from 218-E-8 Demolition Site operations will be addressed in this closure plan in accordance with WAC 173-303-610(2)(b)(i)

  11. Tridimensional modelling and resource estimation of the mining waste piles of São Domingos mine, Iberian Pyrite Belt, Portugal

    Science.gov (United States)

    Vieira, Alexandre; Matos, João; Lopes, Luis; Martins, Ruben

    2016-04-01

    Located in the Iberian Pyrite Belt (IPB) northern sector, near the Portuguese/Spanish border, the outcropping São Domingos deposit was mined since Roman time. Between 1854 and 1966 the Mason & Barry Company developed open pit excavation until 120 m depth and underground mining until 420 m depth. The São Domingos subvertical deposit is associated with felsic volcanics and black shales of the IPB Volcano-Sedimentary Complex and is represented by massive sulphide and stockwork ore (py, cpy, sph, ga, tt, aspy) and related supergene enrichment ore (hematite gossan and covellite/chalcocite). Different mine waste classes were mapped around the old open pit: gossan (W1), felsic volcanic and shales (W2), shales (W3) and mining waste landfill (W4). Using the LNEG (Portuguese Geological Survey) CONASA database (company historical mining waste characterization based on 162 shafts and 160 reverse circulation boreholes), a methodology for tridimensional modelling mining waste pile was followed, and a new mining waste resource is presented. Considering some constraints to waste removal, such as the Mina de São Domingos village proximity of the wastes, the industrial and archaeological patrimony (e.g., mining infrastructures, roman galleries), different resource scenarios were considered: unconditioned resources (total estimates) and conditioned resources (only the volumes without removal constraints considered). Using block modelling (SURPAC software) a mineral inferred resource of 2.38 Mt @ 0.77 g/t Au and 8.26 g/t Ag is estimated in unconditioned volumes of waste. Considering all evaluated wastes, including village areas, an inferred resource of 4.0 Mt @ 0.64 g/t Au and 7.30 g/t Ag is presented, corresponding to a total metal content of 82,878 oz t Au and 955,753 oz t Ag. Keywords. São Domingos mine, mining waste resources, mining waste pile modelling, Iberian Pyrite Belt, Portugal

  12. NORM levels in Spanish pit lakes and their impact in neighboring environments

    Energy Technology Data Exchange (ETDEWEB)

    Manjon, G.; Galvan, J.A.; Mantero, J.; Diaz, I.; Garcia-Tenorio, R. [University of Seville (Spain)

    2014-07-01

    The Iberian Pyrite Belt (IPB) is a part of the South Zone of the Hercynian Iberian Massif (SW of Iberian Peninsula), being pyrite (FeS{sub 2}) the main mineral associated to this volcano-sedimentary complex. The intensive mining activities in the area, which started in the Roman Empire, have generated mine pits where underground and/or rainwater are stored. These stored waters have produced oxidation of pyrite and, consequently, the pH of pit water has become acid (pH around 2), causing the dissolution of metals and natural radionuclides. The main objective of this work is to show and discuss the levels found for different natural radionuclides (mainly uranium isotopes and daughters via α/γ spectrometry) in water samples and sediments collected from several mine pit lakes located in the south-west of Spain. The waters of the studied pit lakes can interact with the environment, and a fraction can be transferred to surrounding aquifers and even to the main river of the zone (the Odiel River). The waters of this river, when cross the mining area, show low pH values and high concentrations of U-isotopes due to acid mining drainage. Through the analysis of several isotope activity ratios, the presence of natural radionuclides in these pit lakes and its influence in the surrounding area and Odiel river will be additionally evaluated. Document available in abstract form only. (authors)

  13. Insights into metals in individual fine particles from municipal solid waste using synchrotron radiation-based micro-analytical techniques

    Institute of Scientific and Technical Information of China (English)

    Yumin Zhu; Hua Zhang; Liming Shao; Pinjing He

    2015-01-01

    Excessive inter-contamination with heavy metals hampers the application of biological treatment products derived from mixed or mechanically-sorted municipal solid waste (MSW).In this study,we investigated fine particles of <2 mm,which are small fractions in MSW but constitute a significant component of the total heavy metal content,using bulk detection techniques.A total of 17 individual fine particles were evaluated using synchrotron radiation-based micro-X-ray fluorescence and micro-X-ray diffraction.We also discussed the association,speciation and source apportionment of heavy metals.Metals were found to exist in a diffuse distribution with heterogeneous intensities and intense hot-spots of <10 μm within the fine particles.Zn-Cu,Pb-Fe and Fe-Mn-Cr had significant correlations in terms of spatial distribution.The overlapped enrichment,spatial association,and the mineral phases of metals revealed the potential sources of fine particles from size-reduced waste fractions (such as scraps of organic wastes or ceramics) or from the importation of other particles.The diverse sources of heavy metal pollutants within the fine particles suggested that separate collection and treatment of the biodegradable waste fraction (such as food waste) is a preferable means of facilitating the beneficial utilization of the stabilized products.

  14. Noble metal behavior during melting of simulated high-level nuclear waste glass feeds

    International Nuclear Information System (INIS)

    Anderson, L.D.; Dennis, T.; Elliott, M.L.; Hrma, P.

    1994-01-01

    Noble metals and their oxides can settle in waste glass melters and cause electrical shorting. Simulate waste feeds from Hanford, Savannah River, and Kernforschungszentrum Karlsruhe were heat treated for 1 hour in a gradient furnace at temperatures ranging from approximately 600 degrees C to 1000 degrees C and examined by electron microscopy to determine shapes, sizes, and distribution of noble metal particles as a function of temperature. Individual noble metal particles and agglomerates of rhodium (Rh), ruthenium (RuO 2 ), and palladium (Pd), as well as their alloys, were seen. The majority of particles and agglomerates were generally less than 10 μm; however, large agglomerations (up to 1 mm) were found in the German feed. 5 refs., 6 figs., 2 tabs

  15. Estimating wastes as energy sources

    Energy Technology Data Exchange (ETDEWEB)

    Baston, V.F.; Gale, L.G.; Burt, B.; Stallings, J.W.

    1980-07-01

    The use of agricultural residues as fuel in fluidized-bed burners is discussed. Laboratory tests which assess the suitability of organic residues for fluidized-bed combustion are described. Residues tested include corn wastes, olive and peach pits, tomato pomace and dried paper mill sludge. It was found that peach pits appeared to be an ideal fuel for fluidized-bed combustion and that the tests can detect and solve potential problems before construction of commercial-size burners.

  16. Metal uptake by native plants and revegetation potential of mining sulfide-rich waste-dumps.

    Science.gov (United States)

    Gomes, Patrícia; Valente, Teresa; Pamplona, Jorge; Braga, Maria Amália Sequeira; Pissarra, José; Gil, José António Grande; de la Torre, Maria Luisa

    2014-01-01

    Waste dumps resulting from metal exploitation create serious environmental damage, providing soil and water degradation over long distances. Phytostabilization can be used to remediate these mining sites. The present study aims to evaluate the behavior of selected plant species (Erica arborea, Ulex europaeus, Agrostis delicatula, and Cytisus multiflorus) that grow spontaneously in three sulfide-rich waste-dumps (Lapa Grande, Cerdeirinha, and Penedono, Portugal). These sites represent different geological, climatic and floristic settings. The results indicate distinctive levels and types of metal contamination: Penedono presents highest sulfate and metal contents, especially As, with low levels of Fe. In contrast, at Lapa Grande and Cerdeirinha Fe, Mn, and Zn are the dominant metals. In accordance, each waste dump develops a typical plant community, providing a specific vegetation inventory. At Penedono, Agrostis delicatula accumulates As, Pb, Cu, Mn, and Zn, showing higher bioaccumulation factors (BF) for Mn (32.1) and As (24.4). At Cerdeirinha, Ulex europaeus has the highest BF for Pb (984), while at Lapa Grande, Erica arborea presents high BF for Mn (9.8) and Pb (8.1). Regarding TF, low values were obtained for most of the metals, especially As (TF < 1). Therefore, the results obtained from representative plant species suggest appropriate behavior for phytostabilization measures.

  17. Invertebrate communities of Arctic tundra ponds as related to proximity to drill site reserve pits

    International Nuclear Information System (INIS)

    Byron, E.; Williams, N.; Hoffman, R.; Elder, B.

    1994-01-01

    Aquatic invertebrate communities were assessed for diversity and abundance in North Slope tundra ponds of Prudhoe Bay, Alaska during the summer of 1992 as part of an evaluation of potential effects of exposure to petroleum drill site reserve pits (previously used for storing drill site wastes). The invertebrate communities of these shallow, tundra ponds provide abundant food for migratory, aquatic birds that use this area during the summer breeding season. The study was designed to compare abundance and diversity estimates of invertebrates in ponds surrounding the drill sites that differed in distance (and presumed exposure) to drill site reserve pits. The pits, themselves, were not sampled as part of this study. Invertebrate abundance and diversity estimates, assessed as standard biological criteria, were evaluated relative to water chemistry of the ponds, distance to the gravel pads or reserve pits, and pond morphometry. The results indicated the importance of pond morphometry in determining the structure of the invertebrate community. Shallow, exposed ponds tended to be dominated by different invertebrate communities than deeper, narrow ponds at the margins of frost polygons. In contrast, pond chemistry and relative exposure to drill sites were not predictive of invertebrate abundance or diversity

  18. Treatment of heterogeneous mixed wastes: Enzyme degradation of cellulosic materials contaminated with hazardous organics and toxic and radioactive metals

    International Nuclear Information System (INIS)

    Vanderberg, L.A.; Foreman, T.M.; Attrep, M. Jr.; Brainard, J.R.; Sauer, N.

    1999-01-01

    The redirection and downsizing of the US Department of Energy's nuclear weapons complex requires that many facilities be decontaminated and decommissioned (D and D). At Los Alamos National Laboratory, much of the low-level radioactive, mixed, and hazardous/chemical waste volume handled by waste management operations was produced by D and D and environmental restoration activities. A combination of technologies--air stripping and biodegradation of volatile organics, enzymatic digestion of cellulosics, and metal ion extraction--was effective in treating a radiologically contaminated heterogeneous paint-stripping waste. Treatment of VOCs using a modified bioreactor avoided radioactive contamination of byproduct biomass and inhibition of biodegradation by toxic metal ions in the waste. Cellulase digestion of bulk cellulose minimized the final solid waste volume by 80%. Moreover, the residue passed TCLP for RCRA metals. Hazardous metals and radioactivity in byproduct sugar solutions were removed using polymer filtration, which employs a combination of water-soluble chelating polymers and ultrafiltration to separate and concentrate metal contaminants. Polymer filtration was used to concentrate RCRA metals and radioactivity into <5% of the original wastewater volume. Permeate solutions had no detectable radioactivity and were below RCRA-allowable discharge limits for Pb and Cr

  19. Radioactive waste management at a Liquid Metal Fast Breeder Reactor

    International Nuclear Information System (INIS)

    Abrams, C.S.; Fryer, R.H.; Witbeck, L.C.

    1979-01-01

    This paper presents the radioactive waste production and management at a Liquid Metal Fast Breeder Reactor-II (EBR-II), which is operated for the US Department of Energy by the Argonne National Laboratory at the Idaho National Engineering Laboratory (INEL). Since this facility, in addition to supplying power has been used to demonstrate the breeder, fuel cycling, and recently operations with defective fuel elements, various categories of waste have been handled safely over some 14 years of operation. Liquid wastes are processed such that the resulting effluent can be discharged to an uncontrolled area. Solid wastes up to 10,000 R/hr are packaged and shipped contamination-free to a disposal site or interim storage with exposures to personnel approximately 10 mrem. Gaseous waste discharges are low such as 143 Ci of noble gases in 1978 and do not have a significant effect on the environment even with operations with breached fuel

  20. PNGMDR 2013-2015. ANDRA's opinion on the development of sector of recycling of VLA ferrous metallic waste

    International Nuclear Information System (INIS)

    2014-01-01

    The scope of this report is to state the ANDRA's opinion on the recycling of very-low-level metallic wastes, and mainly ferrous metallic wastes which are the main stream of them. After having evoked a study jointly performed by EDF, AREVA, the CEA and the ANDRA to assess the technical and economic feasibility of a valorisation of very-low-level metallic wastes in the nuclear sector, this study proposes an assessment of ferrous metals which might be recycled over about thirty years. After having outlined the strong motivation of the ANDRA for such a recycling, the report proposes an overview of the heterogeneous stream of metallic wastes, by distinguishing scrap materials from very heterogeneous origins like those brought to the Cires storage centre, and those with more homogeneous origins (for example, from dismantling activities). The next part proposes an overview of various non coordinated initiatives, notably by the ANDRA, on different storage sites. The report identifies the keys for a successful recycling of contaminated metals in Europe, and the main challenges for the recycling of very-low-level ferrous metal in France (in competition with direct storage, and with the application of the risk-related regulation for some metallic wastes). Some proposals made by the ANDRA are then stated: a reference industrial scheme, and a coordination of actors under the auspices of the State

  1. Examinations of content of heavy metals in municipal solid waste and produced compost

    International Nuclear Information System (INIS)

    Golimowski, J.; Tykarska, A.; Orzechowska, K.

    1993-01-01

    The basic methods of utilization of municipal solid waste are biothermic and aerobic methods to compost. The content of heavy metals in composts depends on the initial their content in wastes as well as on the compost process. The voltammetric method has been applied for measurement of concentration of Zn, Cd, Pb, Cu, Cr, Ni and Hg in the waste and composts samples. (author). 24 refs, 2 figs, 3 tabs

  2. What will we do with 104,000,000 cubic feet of Fernald waste?

    International Nuclear Information System (INIS)

    Motl, G.P.; Krieger, G.J.

    1995-01-01

    The Fernald Site, a Department of Energy (DOE) uranium metal production facility that ceased production in 1989, is now being remediated by the DOE under terms of a Consent Agreement with the United States Environmental Protection Agency (USEPA) and a Consent Decree with the State of Ohio. It is estimated that the cleanup will generate 104,000,000 cubic feet of low-level radioactive waste including construction debris, pit sludge, radium residue and a huge volume of uranium contaminated soil. The waste handling strategy for this huge volume of waste includes minimizing remedial waste generation, recycling material when economically feasible, free-releasing clean material and volume reduction. It is anticipated that large scale radium residue vitrification and sludge drying equipment/facilities will be constructed onsite for waste treatment prior to off-site disposal. Fernald waste disposition will include both onsite disposal (if approved under CERCLA) and off-site disposal at both commercial and DOE waste disposal facilities. The waste disposition strategy selected reflects a diverse variety of technical, political, regulatory and economic factors. This presentation will describe the current views at Fernald on open-quotes what will we do with 104,000,000 cubic feet of Fernald waste.close quotes

  3. Waste acid/metal solution reduction and recovery by vacuum distillation

    International Nuclear Information System (INIS)

    Jones, E.O.; Wilcox, W.A.; Johnson, N.T.; Bowdish, F.W.

    1995-01-01

    Processes involving distillation under reduced pressure were developed at the Pacific Northwest Laboratory several years ago to recover spent acid solutions generated during the manufacture of nuclear fuel for the N-Reactor at the Hanford site. Following construction and testing of a pilot-plant, the technology was licensed to Viatec Recovery Systems, Inc. for commercialization. The technology developed included specialized distillation and rectification of volatile acids, removal of water and/or volatile acid from sulfuric acid, and precipitation of salts. A key feature of the Waste Acid Detoxification and Reclamation (WADR) technology is the development and use of advanced thermoplastic and fluoropolymer materials of construction in all critical process equipment. The technology was then expanded to include crystallization to recover metal salts for possible reuse. Economic and environmental advantages of the procedures include recovery of acids for reuse, simplification or elimination of the disposal of waste solutions, and possible recovery of metals. Industries expected to benefit from such applications include galvanizing, electroplating, sand leaching and any where metals are cleaned in acid solutions. Currently a modular system has been assembled for recovery of several different spent acid solutions

  4. Recovery of uranium and accompanying metals from various types of industrial wastes

    International Nuclear Information System (INIS)

    Chajduk, E.; Danko, B.; Gajda, D.; Zakrzewska, G.; Harasimowicz, M.; Bieluszka, P.

    2014-01-01

    On January 28"t"h 2014 the Program of Polish Nuclear Energy was signed by Polish Government. According to this program Poland has to secure a constant supply of uranium for Polish NPPs in the future. Uranium in Poland occurs in Vistula Spit area in sandstone rocks and Podlasie Depression area in black dictyonema shales, which are low grade ores. Scarce uranium resources stimulate interest in its recovery from secondary resources as potential raw materials. Industrial wastes and by-products were considered as a source of uranium in this studies. Apart from uranium other valuable metals (e.g. vanadium, molybdenum or lanthanides) were recovered to improve the economy of the process. Three types of industrial wastes were examined: flotation tailings from the copper industry, phosphoric acid from the fertilizer industry and fracturing fluid from shale gas exploitation. Metals from flotation tailings were separated in two steps: 1) acidic leaching of the flotation waste using sulfuric acid solution and 2) separation of metals by ion-exchange chromatography. All the liquid samples were analyzed by ICP-MS method to determine the separation efficiency of the process. Uranium was recovered from phosphoric acid by high-pressure membrane filtration or by extraction/stripping integrated processes applying membrane modules Liquid-Cel® Extra-Flow (Celgard). Aqueous solutions after hydraulic fracturing are very diverse in terms of chemical composition, depending on borehole and fracturing technology applied. The content of various substances in backflow fluid depends on mechanical behavior and chemical composition of shale. Organic matter content in this type of waste did not exceed 1% usually, but the salinity is high. Initially, organic pollutants were removed and next the fluid was purified by combined various ion-exchangers. Individual metals were selectively eluted from ion-exchanger by combination of different eluents. The content of metals in samples was analyzed by ICP

  5. Baseline Risk Assessment for the F-Area Burning/Rubble Pits and Rubble Pit

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, E. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1996-03-01

    This document provides an overview of the Savannah River Site (SRS) and a description of the F-Area Burning/Rubble Pits (BRPs) and Rubble Pit (RP) unit. It also describes the objectives and scope of the baseline risk assessment (BRA).

  6. Assessment of biotechnological strategies for the valorization of metal bearing wastes

    International Nuclear Information System (INIS)

    Beolchini, Francesca; Fonti, Viviana; Dell’Anno, Antonio; Rocchetti, Laura; Vegliò, Francesco

    2012-01-01

    Highlights: ► We examine biological strategies to valorize different metal rich solid waste. ► Bacteria play a key role in the mobilization of Zn and Y from fluorescent powders. ► Ferrous iron is crucial for the bioleaching of Ni, V, Mo from spent catalysts. ► No biological effect is observed for Ni, Zn, As, Cr mobilisation from sediments. - Abstract: The present work deals with the application of biotechnology for the mobilization of metals from different solid wastes: end of life industrial catalysts, heavy metal contaminated marine sediments and fluorescent powders coming from a cathode ray tube glass recycling process. Performed experiments were aimed at assessing the performance of acidophilic chemoautotrophic Fe/S-oxidizing bacteria for such different solid matrices, also focusing on the effect of solid concentration and of different substrata. The achieved results have evidenced that metal solubilization seems to be strongly influenced by the metal speciation and partitioning in the solid matrix. No biological effect was observed for Ni, Zn, As, Cr mobilization from marine sediments (34%, 44%, 15%, 10% yields, respectively) due to metal partitioning. On the other hand, for spent refinery catalysts (Ni, V, Mo extractions of 83%, 90% and 40%, respectively) and fluorescent powders (Zn and Y extraction of 55% and 70%, respectively), the improvement in metal extraction observed in the presence of a microbial activity confirms the key role of Fe/S oxidizing bacteria and ferrous iron. A negative effect of solid concentration was in general observed on bioleaching performances, due to the toxicity of dissolved metals and/or to the solid organic component.

  7. Impact of metals in surface matrices from formal and informal electronic-waste recycling around Metro Manila, the Philippines, and intra-Asian comparison

    International Nuclear Information System (INIS)

    Fujimori, Takashi; Takigami, Hidetaka; Agusa, Tetsuro; Eguchi, Akifumi; Bekki, Kanae; Yoshida, Aya; Terazono, Atsushi; Ballesteros, Florencio C.

    2012-01-01

    Highlights: ► We quantified 11 metals in surface matrices from e-waste recycling sites at the Philippines. ► Dust had statistical higher levels of metal contamination and health risk compared to soil. ► Formal and informal sites had different metal contaminations. ► Intra-Asian comparison provided common insight on metal contamination from e-waste recycling. - Abstract: We report concentrations, enrichment factors, and hazard indicators of 11 metals (Ag, As, Cd, Co, Cu, Fe, In, Mn, Ni, Pb, and Zn) in soil and dust surface matrices from formal and informal electronic waste (e-waste) recycling sites around Metro Manila, the Philippines, referring to soil guidelines and previous data from various e-waste recycling sites in Asia. Surface dust from e-waste recycling sites had higher levels of metal contamination than surface soil. Comparison of formal and informal e-waste recycling sites (hereafter, “formal” and “informal”) revealed differences in specific contaminants. Formal dust contained a mixture of serious pollutant metals (Ni, Cu, Pb, and Zn) and Cd (polluted modestly), quite high enrichment metals (Ag and In), and crust-derived metals (As, Co, Fe, and Mn). For informal soil, concentration levels of specific metals (Cd, Co, Cu, Mn, Ni, Pb, and Zn) were similar among Asian recycling sites. Formal dust had significantly higher hazardous risk than the other matrices (p < 0.005), excluding informal dust (p = 0.059, almost significant difference). Thus, workers exposed to formal dust should protect themselves from hazardous toxic metals (Pb and Cu). There is also a high health risk for children ingesting surface matrices from informal e-waste recycling sites.

  8. Study on waste waters of metal finishing industries around Lahore metropolitan area

    International Nuclear Information System (INIS)

    Khan, Izhar-ul-Haq; Mahmood, F.; Tufail, S.; Naeem, M.

    2002-01-01

    Study was undertaken on the waste water samples from metal finishing industries of Lahore metropolitan area for the evaluation of metallic impurities. The metal finishing industry was classified into three categories i. e. medium scale, small scale and cottage scale industry. About 93 wastewater samples were collected from various metal finishing industries around Lahore metropolitan area. In addition to toxic elements like cadmium, nickel and zinc the other parameters such as hydrogen ion concentration (pH), Electrical conductivity (EC) and Total Dissolved Salts (TDS) were also determined. (author)

  9. Formal recycling of e-waste leads to increased exposure to toxic metals: an occupational exposure study from Sweden.

    Science.gov (United States)

    Julander, Anneli; Lundgren, Lennart; Skare, Lizbet; Grandér, Margaretha; Palm, Brita; Vahter, Marie; Lidén, Carola

    2014-12-01

    Electrical and electronic waste (e-waste) contains multiple toxic metals. However, there is currently a lack of exposure data for metals on workers in formal recycling plants. The objective of this study was to evaluate workers' exposure to metals, using biomarkers of exposure in combination with monitoring of personal air exposure. We assessed exposure to 20 potentially toxic metals among 55 recycling workers and 10 office workers at three formal e-waste recycling plants in Sweden. Workers at two of the plants were followed-up after 6 months. We collected the inhalable fraction and OFC (37-mm) fraction of particles, using personal samplers, as well as spot samples of blood and urine. We measured metal concentrations in whole blood, plasma, urine, and air filters using inductively coupled plasma-mass spectrometry following acid digestion. The air sampling indicated greater airborne exposure, 10 to 30 times higher, to most metals among the recycling workers handling e-waste than among the office workers. The exposure biomarkers showed significantly higher concentrations of chromium, cobalt, indium, lead, and mercury in blood, urine, and/or plasma of the recycling workers, compared with the office workers. Concentrations of antimony, indium, lead, mercury, and vanadium showed close to linear associations between the inhalable particle fraction and blood, plasma, or urine. In conclusion, our study of formal e-waste recycling shows that workers performing recycling tasks are exposed to multiple toxic metals. Copyright © 2014. Published by Elsevier Ltd.

  10. A study of the metal content of municipal solid waste. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Churney, K.L.; Domalski, E.S.

    1998-01-01

    Knowledge of the content of toxic components, so called pollutant precursors, in the municipal solid waste (MSW) stream is essential to development of the strategies for source reduction and reuse, recycling, composting and disposal. Data are scarce; trends in composition for any locality even more so. In a previous study the total and water soluble chlorine content of the components of municipal solid waste were determined from sampling studies at two sites, Baltimore County, MD, and Brooklyn, NY, each for a five day period. The total sulfur content of the combined combustible components was also determined. Because of the scarcity of data and synergistic effects, it seemed appropriate to determine the heavy metal content of the preceding material prior to its disposal. The metals chosen were the so-called priority pollutant metals (PPM): antimony, arsenic, beryllium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, thallium, and zinc.

  11. Burn Pit Emissions Exposure and Respiratory and Cardiovascular Conditions Among Airborne Hazards and Open Burn Pit Registry Participants.

    Science.gov (United States)

    Liu, Jason; Lezama, Nicholas; Gasper, Joseph; Kawata, Jennifer; Morley, Sybil; Helmer, Drew; Ciminera, Paul

    2016-07-01

    The aim of this study was to determine how burn pit emissions exposure is associated with the incidence of respiratory and cardiovascular conditions. We examined the associations between assumed geographic and self-reported burn pit emissions exposure and respiratory and cardiovascular outcomes in participants of the Airborne Hazards and Open Burn Pit Registry. We found significant dose-response associations for higher risk of self-reported emphysema, chronic bronchitis, or chronic obstructive pulmonary disease with increased days of deployment within 2 miles of selected burn pits (P-trend = 0.01) and self-reported burn pit smoke exposure (P-trend = 0.0005). We found associations between burn pit emissions exposure and higher incidence of post-deployment self-reported respiratory and cardiovascular conditions, but these findings should be interpreted with caution because the surrogate measurements of burn pit emissions exposure in this analysis may not reflect individual exposure levels.

  12. Evaluation of thermal hydraulics characteristics of natural cooling low level radioactive waste storage system

    International Nuclear Information System (INIS)

    Yoshii, Toshihiro; Iwaki, Chikako; Ikeda, Tatsumi; Ikeda, Hiroshi; Koyama, Tomonori; Usui, Nobuhiko; Watanabe, Hisao; Masaki, Yoshikazu

    2012-01-01

    It is necessary to design a low level radioactive waste storage system so that the decay heat of radioactive waste does not breach the structural safety limit. Currently, this waste storage system is designed as a natural cooling system, which continuously cools the radioactive waste without an active device. It consists simply of a storage pit for radioactive waste and air inlet and outlet ducts. The radioactive waste is cooled by natural convective air flow, which is generated by the buoyancy of heated air due to the decay heat of radioactive waste. It is important to clarify the flow characteristics in the systems in order to evaluate the cooling performance. The air mass flow rate through the system is determined by the balance between the natural convective flow force and pressure loss within the system. Therefore, the pressure drop and flow pattern in the waste storage pit are important flow characteristics. In this study, the pressure drop and air temperature distribution, greatly influenced by the flow pattern in the pit, were measured using a 1/5 scale model and compared with the results obtained from CFD. Flow network analysis, which is a simple model that simulates the flow by nodes and junctions, was conducted and its validity was confirmed by experimental results and CFD. (author)

  13. Kinetics of growth of semi-spheric pittings in the vicinity repassivation potential depending on bulk concentration of activator anions

    International Nuclear Information System (INIS)

    Frejman, L.I.

    1985-01-01

    A general case of semi-spheric pittings development in aqueous solutions of electrolyte of NaCl or LiCl type at different values of C 0 , usually studied in the range approximately equal to 10 -5 -10 -3 g-ionxcm -3 (approximately equal to 10 -2 -10 0 g-ionxl -1 ), has been analyzed. On the basis of experimental data on participation of anion-activators and water molecules in the process of metal dissolution in pitting, and using the previously obtained equations, kinetics of open and closed semi-spheric pittings during galvanostatic anode polarization in neutral chloride solutions with different volumetric concentration of Cl - -ions (C 0 ) has been considered. In a general case the process kinetics is described by a complex equation, the boundary, more simple forms of which, correspond to the initial (A) and subsequent (B) stages of open pitting development, or to certain stable conditions of closed pitting development

  14. Spatial distribution of heavy metal contamination in soils near a primitive e-waste recycling site.

    Science.gov (United States)

    Quan, Sheng-Xiang; Yan, Bo; Yang, Fan; Li, Ning; Xiao, Xian-Ming; Fu, Jia-Mo

    2015-01-01

    The total concentrations of 12 heavy metals in surface soils (SS, 0-20 cm), middle soils (MS, 30-50 cm) and deep soils (DS, 60-80 cm) from an acid-leaching area, a deserted paddy field and a deserted area of Guiyu were measured. The results showed that the acid-leaching area was heavily contaminated with heavy metals, especially in SS. The mean concentrations of Ni, Cu, Zn, Cd, Sn, Sb and Pb in SS from the acid-leaching area were 278.4, 684.1, 572.8, 1.36, 3,472, 1,706 and 222.8 mg/kg, respectively. Heavy metal pollution in the deserted paddy field was mainly concentrated in SS and MS. The average values of Sb in SS and MS from the deserted paddy field were 16.3 and 20.2 mg/kg, respectively. However, heavy metal contamination of the deserted area was principally found in the DS. Extremely high concentrations of heavy metals were also observed at some special research sites, further confirming that the level of heavy metal pollution was very serious. The geoaccumulation index (Igeo) values revealed that the acid-leaching area was severely polluted with heavy metals in the order of Sb > Sn > Cu > Cd > Ni > Zn > Pb, while deserted paddy field was contaminated predominately by metals in the order of Sb > Sn > Cu. It was obvious that the concentrations of some uncommon contaminants, such as Sb and Sn, were higher than principal contaminants, such as Ni, Cu, Zn and Pb, suggesting that particular attention should be directed to Sn and Sb contamination in the future research of heavy metals in soils from e-waste-processing areas. Correlation analysis suggested that Li and Be in soils from the acid-leaching area and its surrounding environment might have originated from other industrial activities and from batteries, whereas Ni, Cu, Zn, Cd, Pb, Sn and Sb contamination was most likely caused by uncontrolled electronic waste (e-waste) processing. These results indicate the significant need for optimisation of e-waste-dismantling technologies and remediation of polluted soil

  15. Study on the behavior of heavy metals during thermal treatment of municipal solid waste (MSW) components.

    Science.gov (United States)

    Yu, Jie; Sun, Lushi; Wang, Ben; Qiao, Yu; Xiang, Jun; Hu, Song; Yao, Hong

    2016-01-01

    Laboratory experiments were conducted to investigate the volatilization behavior of heavy metals during pyrolysis and combustion of municipal solid waste (MSW) components at different heating rates and temperatures. The waste fractions comprised waste paper (Paper), disposable chopstick (DC), garbage bag (GB), PVC plastic (PVC), and waste tire (Tire). Generally, the release trend of heavy metals from all MSW fractions in rapid-heating combustion was superior to that in low-heating combustion. Due to the different characteristics of MSW fractions, the behavior of heavy metals varied. Cd exhibited higher volatility than the rest of heavy metals. For Paper, DC, and PVC, the vaporization of Cd can reach as high as 75% at 500 °C in the rapid-heating combustion due to violent combustion, whereas a gradual increase was observed for Tire and GB. Zn and Pb showed a moderate volatilization in rapid-heating combustion, but their volatilities were depressed in slow-heating combustion. During thermal treatment, the additives such as kaolin and calcium can react or adsorb Pb and Zn forming stable metal compounds, thus decreasing their volatilities. The formation of stable compounds can be strengthened in slow-heating combustion. The volatility of Cu was comparatively low in both high and slow-heating combustion partially due to the existence of Al, Si, or Fe in residuals. Generally, in the reducing atmosphere, the volatility of Cd, Pb, and Zn was accelerated for Paper, DC, GB, and Tire due to the formation of elemental metal vapor. TG analysis also showed the reduction of metal oxides by chars forming elemental metal vapor. Cu2S was the dominant Cu species in reducing atmosphere below 900 °C, which was responsible for the low volatility of Cu. The addition of PVC in wastes may enhance the release of heavy metals, while GB and Tire may play an opposite effect. In controlling heavy metal emission, aluminosilicate- and calcium-based sorbents can be co-treated with fuels. Moreover

  16. Development of engineering parameters for the design of metal biosorption waste treatment systems

    Energy Technology Data Exchange (ETDEWEB)

    Graham, W.S.

    1991-12-03

    Untreated landfill leachates and wastes from metal plating and mining operations are sources of environmental contamination by heavy metals. Because of their toxicity and potential for accumulation, the discharge of heavy metals must be controlled. Standard physical and chemical treatments used to remove metals from wastes such as concentration by electro-precipitation, ion exchange, solvent extraction, evaporative recovery, and conventional precipitation, are usually expensive and produce high quantities of sludge. Biosorption is the removal of metals from aqueous solutions by microorganisms. It is called biosorption rather than bioadsorption or bioaccumulation because the mechanisms of removal are not restricted to adsorption or metabolic uptake and so the more general term is preferable and has come to be accepted. In this thesis the focus is one two microorganisms and two metals. However, the possible combinations of conditions such as pH, relative metal molarities, time of contact, and organism are numerous. These experiments are designed to provide optimized parameters to facilitate the design of a functioning biosorption system. The two metals chosen for study are copper and lead in aqueous solution. The two types of microorganisms chosen for testing include an actinomycete and a fungus. The purpose of this research is to identify the significant engineering parameters to be evaluated include reaction rates, equilibrium partitioning of metal ions between those in solution and those removed to the cells, optimum pH for achieving the removal or recovery goal, and biosorption selectivity for one metal over another.

  17. Persimmon leaf bio-waste for adsorptive removal of heavy metals from aqueous solution.

    Science.gov (United States)

    Lee, Seo-Yun; Choi, Hee-Jeong

    2018-03-01

    The aim of this study was to investigate heavy metal removal using waste biomass adsorbent, persimmon leaves, in an aqueous solution. Persimmon leaves, which are biomaterials, have a large number of hydroxyl groups and are highly suitable for removal of heavy metals. Therefore, in this study, we investigated the possibility of removal of Cu, Pb, and Cd in aqueous solution by using raw persimmon leaves (RPL) and dried persimmon leaves (DPL). Removal of heavy metals by RPL and DPL showed that DPL had a 10%-15% higher removal than RPL, and the order of removal efficiency was found to be Pb > Cu > Cd. The pseudo-second order model was a better fit to the heavy metal adsorption experiments using RPL and DPL than the pseudo-first order model. The adsorption of Cu, Pb, and Cd by DPL was more suitable with the Freundlich isothermal adsorption and showed an ion exchange reaction which occurred in the uneven adsorption surface layer. The maximum adsorption capacity of Cu, Pb, and Cd was determined to be 19.42 mg/g, 22.59 mg/g, and 18.26 mg/g, respectively. The result of the adsorption experiments showed that the n value was higher than 2 regardless of the dose, indicating that the heavy metal adsorption on DPL was easy. In the thermodynamic experiment, ΔG° was a negative value, and ΔH° and ΔS° were positive values. It can be seen that the heavy metal adsorption process using DPL was spontaneous in nature and was an endothermic process. Moreover, as the temperature increased, the adsorption increased, and the affinity of heavy metal adsorption to DPL was very good. This experiment, in which heavy metals are removed using the waste biomass of persimmon leaves is an eco-friendly new bioadsorbent method because it can remove heavy metals without using chemicals while utilizing waste recycling. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Closing the Loop: Key Role of Iron in Metal-Bearing Waste Recycling

    Directory of Open Access Journals (Sweden)

    Sedlakova-Kadukova J.

    2017-09-01

    Full Text Available The role of iron in metal-bearing waste bioleaching was studied. Four various types of waste (printed circuit boards (PCBs, Ni-Cd batteries, alkaline batteries and Li-ion batteries were treated by bioleaching using the acidophilic bacteria A. ferrooxidans and A. thiooxidans (separately or in mixture. Role of main leaching agents (Fe3+ ions or sulphuric acid was simulated in abiotic experiments. Results showed that oxidation abilities of Fe3+ ions were crucial for recovery of Cu and Zn from PCBs, with the efficiencies of 88% and 100%, respectively. To recover 68% of Ni from PCBs, and 55% and 100% of Ni and Cd, respectively, from Ni-Cd batteries both oxidation action and hydrolysis of Fe3+ were required. The importance of Fe2+ ions as a reducing agent was showed in bioleaching of Co from Li-ion batteries and Mn from alkaline batteries. The efficiency of the processes has increased by 70% and 40% in Co and Mn bioleaching, respectively, in the presence of Fe2+ ions. Based on the results we suggest the integrated biometallurgical model of metal-bearing waste recycling in the effort to develop zero-waste and less energy-dependent technologies.

  19. Heavy metal removal from municipal solid waste fly ash by chlorination and thermal treatment

    International Nuclear Information System (INIS)

    Nowak, B.; Pessl, A.; Aschenbrenner, P.; Szentannai, P.; Mattenberger, H.; Rechberger, H.; Hermann, L.; Winter, F.

    2010-01-01

    Municipal solid waste (MSW) fly ash is classified as a hazardous material because it contains high amounts of heavy metals. For decontamination, MSW fly ash is first mixed with alkali or alkaline earth metal chlorides (e.g. calcium chloride) and water, and then the mixture is pelletized and treated in a rotary reactor at about 1000deg. C. Volatile heavy metal compounds are formed and evaporate. In this paper, the effect of calcium chloride addition, gas velocity, temperature and residence time on the separation of heavy metals are studied. The fly ash was sampled at the waste-to-energy plant Fernwaerme Wien/Spittelau (Vienna, Austria). The results were obtained from batch tests performed in an indirectly heated laboratory-scale rotary reactor. More than 90% of Cd and Pb and about 60% of Cu and 80% of Zn could be removed in the experiments.

  20. Laboratory scale vitrification of low-level radioactive nitrate salts and soils from the Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Shaw, P.; Anderson, B.

    1993-07-01

    INEL has radiologically contaminated nitrate salt and soil waste stored above and below ground in Pad A and the Acid Pit at the Radioactive Waste Management Complex. Pad A contain uranium and transuranic contaminated potassium and sodium nitrate salts generated from dewatered waste solutions at the Rocky Flats Plant. The Acid Pit was used to dispose of liquids containing waste mineral acids, uranium, nitrate, chlorinated solvents, and some mercury. Ex situ vitrification is a high temperature destruction of nitrates and organics and immobilizes hazardous and radioactive metals. Laboratory scale melting of actual radionuclides containing INEL Pad A nitrate salts and Acid Pit soils was performed. The salt/soil/additive ratios were varied to determine the range of glass compositions (resulted from melting different wastes); maximize mass and volume reduction, durability, and immobilization of hazardous and radioactive metals; and minimize viscosity and offgas generation for wastes prevalent at INEL and other DOE sites. Some mixtures were spiked with additional hazardous and radioactive metals. Representative glasses were leach tested and showed none. Samples spiked with transuranic showed low nuclide leaching. Wasteforms were two to three times bulk densities of the salt and soil. Thermally co-processing soils and salts is an effective remediation method for destroying nitrate salts while stabilizing the radiological and hazardous metals they contain. The measured durability of these low-level waste glasses approached those of high-level waste glasses. Lab scale vitrification of actual INEL contaminated salts and soils was performed at General Atomics Laboratory as part of the INEL Waste Technology Development and Environmental Restoration within the Buried Waste Integrated Demonstration Program

  1. A practical approach to proving waste metals suitable for consignment as radiologically exempt materials - 59266

    International Nuclear Information System (INIS)

    Carvel, Iain; Gunn, Richard D.; Orr, Christopher H.; Strange, Robin

    2012-01-01

    Building 220 at Harwell was built by the Ministry of Works as a Radiochemical Research and Development facility in the latter part of the 1940's. The facility has been operational since 1949 and has been extended several times, most notably the Plutonium Glove Box Wing in the 1950's and the Remote Handling Wing in the 1980's. Only the Remote Handling wing remains operational, processing Historic Waste which is being recovered from storage holes elsewhere on site. The remainder of the facility is undergoing progressive strip out and decommissioning. In the Plutonium Wing and associated areas the waste 'fingerprint' (nuclide vector) consists predominately of alpha emitting radionuclides. Decommissioning and Decontamination (D and D) operations often result in the production of large volumes of scrap metal waste with little or no radioactive contamination. Proving that the waste is clean can be costly and time consuming, as the shape and size of the metallic waste items often means that it is difficult or impossible to monitor all surfaces using conventional hand-held survey meters. This is a particular problem for alpha contamination measurement. Traditional radiological surveying techniques are very labour intensive and involve surveyors checking every surface using hand held instruments and smear sampling the hard to access areas. Even then 100% monitoring cannot be guaranteed. An alternative to traditional methods is the Long Range Alpha Detection (LRAD) technique which remotely detects and measures secondary ionization created in air by alpha particle interactions, allowing extremely low levels of alpha contamination to be measured. A survey system, IonSens R , using the LRAD technique, was developed by BNFL Instruments Ltd (now Babcock Nuclear) which allows rapid surveying of scrap metal for alpha contamination at very low levels. Two versions of this system exist but both essentially comprise a measurement chamber into which scrap metal is placed and sealed

  2. Pitting corrosion inhibition of aluminum 2024 by Bacillus biofilms secreting polyaspartate or gamma-polyglutamate.

    Science.gov (United States)

    Ornek, D; Jayaraman, A; Syrett, B C; Hsu, C-H; Mansfeld, F B; Wood, T K

    2002-04-01

    Pitting corrosion of aluminum 2024 in Luria Bertani medium was reduced by the secretion of anionic peptides by engineered and natural Bacillus biofilms and was studied in continuous reactors using electrochemical impedance spectroscopy. Compared to sterile controls, pitting was reduced dramatically by the presence of the biofilms. The secretion of a 20 amino acid polyaspartate peptide by an engineered Bacillus subtilis WB600/pBE92-Asp biofilm slightly reduced the corrosion rate of the passive aluminum alloy at pH 6.5; however, the secretion of gamma-polyglutamate by a Bacillus licheniformis biofilm reduced the corrosion rate by 90% (compared to the B. subtilis WB600/pBE92 biofilm which did not secrete polyaspartate or gamma-polyglutamate). The corrosion potential ( E(corr)) of aluminum 2024 was increased by about 0.15-0.44 V due to the formation of B. subtilis and B. licheniformis biofilms as compared to sterile controls. The increase of E(corr) and the observed prevention of pitting indicate that the pitting potential ( E(pit)) had increased. This result and the further decrease of corrosion rates for the passive aluminum alloy suggest that the rate of the anodic metal dissolution reaction was reduced by an inhibitor produced by the biofilms. Purified gamma-polyglutamate also decreased the corrosion rates of aluminum 2024.

  3. Parturition pit: the bony imprint of vaginal birth

    International Nuclear Information System (INIS)

    McArthur, Tatum A.; Meyer, Isuzu; Jackson, Bradford; Pitt, Michael J.; Larrison, Matthew C.

    2016-01-01

    To retrospectively evaluate for pits along the dorsum of the pubic body in females and compare the presence/absence of these pits to vaginal birth data. We retrospectively reviewed females with vaginal birth data who underwent pelvic CT. The presence of pits along the dorsum of the pubic body, pit grade (0 = not present; 1 = faintly imperceptible; 2 = present; 3 = prominent), and the presence of osteitis condensans ilii, preauricular sulcus, and sacroiliac joint vacuum phenomenon were assessed on imaging. Musculoskeletal radiologists who were blinded to the birth data evaluated the CTs. 48 males were also evaluated for the presence of pits. 482 female patients underwent CT pelvis and 171 were excluded due to lack of vaginal birth data. Of the 311 study patients, 262 had prior vaginal birth(s) and 194 had pits on CT. Only 7 of the 49 patients without prior vaginal birth had pits. There was a statistically significant association between vaginal birth and presence of pits (p < 0.0001). Patients with more prominent pits (grades 2/3) had a greater number of vaginal births. As vaginal deliveries increased, the odds of having parturition pits greatly increased, adjusting for age and race at CT (p < 0.0001). No males had pits. Our study indicates that parturition pits are associated with prior vaginal birth and should be considered a characteristic of the female pelvis. The lytic appearance of prominent pits on imaging can simulate disease and create a diagnostic dilemma for interpreting radiologists. (orig.)

  4. New Engineering Solutions in Creation of Mini-BOF for Metallic Waste Recycling

    Science.gov (United States)

    Eronko, S. P.; Gorbatyuk, S. M.; Oshovskaya, E. V.; Starodubtsev, B. I.

    2017-12-01

    New engineering solutions used in design of the mini melting unit capable of recycling industrial and domestic metallic waste with high content of harmful impurities are provided. High efficiency of the process technology implemented with its use is achieved due to the possibility of the heat and mass transfer intensification in the molten metal bath, controlled charge into it of large amounts of reagents in lumps and in fines, and cut-off of remaining process slag during metal tapping into the teeming ladle.

  5. Post-pit optimization strategic alignment

    OpenAIRE

    Breed, M.F.; van Heerden, D.

    2016-01-01

    Successful development of projects or life-of-mine strategies requires an understanding of the relative sensitivity of value drivers such as grade, tonnage, energy costs, direct operational costs, and recoveries. For example, the results could vary significantly depending on the grade strategy, given a specific orebody amenable to open pitting. Pit optimization is a very powerful tool widely used in the industry to determine the pit shell with the most attractive value potential. Based on the...

  6. Characterization of the Burma Road Rubble Pit at the Savannah River Site, Aiken, South Carolina

    International Nuclear Information System (INIS)

    Ward, K.G.; Frazier, W.L.; McAdams, T.D.; McFalls, S.L.; Rabin, M.; Voss, L.

    1996-01-01

    The Burma Road Rubble Pit (BRRP) is located at the Savannah River Site (SRS). The BRRP unit consists of two unlined earthen pits dug into surficial soil and filled with various waste materials. It was used from 1973--1983 for the disposal of dry inert rubble such as metal, concrete, lumber, poles, light fixtures, and glass. No record of the disposal of hazardous substances at the BRRP has been found. In 1983, the BRRP was closed by covering it with soil. In September 1988, a Ground Penetrating Radar survey detected three disturbed areas of soil near the BRRP, and a detailed and combined RCRA Facility Investigation/Remedial Investigation was conducted from November 1993 to February 1994 to determine whether hazardous substances were present in the subsurface, to evaluate the nature and extent of contamination, and to evaluate the risks posed to the SRS facility due to activities conducted at the BRRP site. Metals, semi-volatile organic compounds, volatile organic compounds, radionuclides and one pesticide (Aldrin) were detected in soil and groundwater samples collected from seventeen BRRP locations. A baseline risk assessment (BRA) was performed quantitatively to evaluate whether chemical and radionuclide concentrations detected in soil and groundwater at the BRRP posed an unacceptable threat to human health and the environment. The exposure scenarios identifiable for the BRRP were for environmental researchers, future residential and occupational land use. The total site noncancer hazard indices were below unity, and cancer risk levels were below 1.0E-06 for the existing and future case environmental researcher scenario. The future case residential and occupational scenarios showed total hazard and risk levels which exceeded US EPA criterion values relative to groundwater scenarios. For the most part, the total carcinogenic risks were within the 1.0E-04 to 1.0E-06 risk range. Only the future adult residential scenario was associated with risks exceeding 1.0E-04

  7. The analysis on the current status of the overseas recycle technology of the metallic radioactive wastes

    International Nuclear Information System (INIS)

    Shin, Jae In; Kim, Hee Reyoung; Jung, Kee Jung

    2002-05-01

    It was understood that regulation criteria for material release varied with countries and that international standards were not setup. But, most advanced countries are continuously studying on the recycling of metallic wastes for the purpose of the reuse of resources and disposal cost reduction. Practically, the advanced countries make a lot of cost profits compared with disposal as their metallic wastes are recycled and reused through technology like melting. The reasonable international standards are also expected to be set in the near future because of the aggressive cooperation between international agencies such as IAEA and NEA toward recycling these wastes. In our case, the recycle criteria for radioactive waste containing radioactive nuclide with long half-life such as Cs-137(half-life: 30y) and Co-60(half-life: 5.26y) including others, which are generated from the nuclear fission or dismantling of nuclear facilities, are not yet established. Therefore, it is required that the recommendation and legalization of the regulatory criteria be carried out for the recycle and reuse of metallic wastes to be generated from the dismantling of domestic nuclear facilities in the future

  8. Enhanced bioleaching efficiency of metals from E-wastes driven by biochar

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shuhua; Zheng, Yue; Yan, Weifu; Chen, Lixiang [CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China); University of Chinese Academy of Sciences, Beijing, 100049 (China); Dummi Mahadevan, Gurumurthy [CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China); Zhao, Feng, E-mail: fzhao@iue.ac.cn [CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 (China)

    2016-12-15

    Electronic wastes (E-wastes) contain a huge amount of valuable metals that are worth recovering. Bioleaching has attracted widespread attention as an environment-friendly and low-cost technology for the recycling of E-wastes. To avoid the disadvantages of being time-consuming or having a relatively low efficiency, biochar with redox activity was used to enhance bioleaching efficiency of metals from a basic E-waste (i.e., printed circuit boards in this study). The role of biochar was examined through three basic processes: Carbon-mediated, Sulfur-mediated and Iron-mediated bioleaching pathways. Although no obvious enhancement of bioleaching performance was observed in the C-mediated and S-mediated systems, Fe-mediated bioleaching was significantly promoted by the participation of biochar, and its leaching time was decreased by one-third compared with that of a biochar-free system. By mapping the dynamic concentration of Fe(II) and Cu(II), biochar was proved to facilitate the redox action between Fe(II) to Fe(III), which resulted in effective leaching of Cu. Two dominant functional species consisting of Alicyclobacillus spp. and Sulfobacillus spp. may cooperate in the Fe-mediated bioleaching system, and the ratio of these two species was regulated by biochar for enhancing the efficiency of bioleaching. Hence, this work provides a method to improve bioleaching efficiency with low-cost solid redox media.

  9. Enhanced bioleaching efficiency of metals from E-wastes driven by biochar

    International Nuclear Information System (INIS)

    Wang, Shuhua; Zheng, Yue; Yan, Weifu; Chen, Lixiang; Dummi Mahadevan, Gurumurthy; Zhao, Feng

    2016-01-01

    Electronic wastes (E-wastes) contain a huge amount of valuable metals that are worth recovering. Bioleaching has attracted widespread attention as an environment-friendly and low-cost technology for the recycling of E-wastes. To avoid the disadvantages of being time-consuming or having a relatively low efficiency, biochar with redox activity was used to enhance bioleaching efficiency of metals from a basic E-waste (i.e., printed circuit boards in this study). The role of biochar was examined through three basic processes: Carbon-mediated, Sulfur-mediated and Iron-mediated bioleaching pathways. Although no obvious enhancement of bioleaching performance was observed in the C-mediated and S-mediated systems, Fe-mediated bioleaching was significantly promoted by the participation of biochar, and its leaching time was decreased by one-third compared with that of a biochar-free system. By mapping the dynamic concentration of Fe(II) and Cu(II), biochar was proved to facilitate the redox action between Fe(II) to Fe(III), which resulted in effective leaching of Cu. Two dominant functional species consisting of Alicyclobacillus spp. and Sulfobacillus spp. may cooperate in the Fe-mediated bioleaching system, and the ratio of these two species was regulated by biochar for enhancing the efficiency of bioleaching. Hence, this work provides a method to improve bioleaching efficiency with low-cost solid redox media.

  10. Enhanced bioleaching efficiency of metals from E-wastes driven by biochar.

    Science.gov (United States)

    Wang, Shuhua; Zheng, Yue; Yan, Weifu; Chen, Lixiang; Dummi Mahadevan, Gurumurthy; Zhao, Feng

    2016-12-15

    Electronic wastes (E-wastes) contain a huge amount of valuable metals that are worth recovering. Bioleaching has attracted widespread attention as an environment-friendly and low-cost technology for the recycling of E-wastes. To avoid the disadvantages of being time-consuming or having a relatively low efficiency, biochar with redox activity was used to enhance bioleaching efficiency of metals from a basic E-waste (i.e., printed circuit boards in this study). The role of biochar was examined through three basic processes: Carbon-mediated, Sulfur-mediated and Iron-mediated bioleaching pathways. Although no obvious enhancement of bioleaching performance was observed in the C-mediated and S-mediated systems, Fe-mediated bioleaching was significantly promoted by the participation of biochar, and its leaching time was decreased by one-third compared with that of a biochar-free system. By mapping the dynamic concentration of Fe(II) and Cu(II), biochar was proved to facilitate the redox action between Fe(II) to Fe(III), which resulted in effective leaching of Cu. Two dominant functional species consisting of Alicyclobacillus spp. and Sulfobacillus spp. may cooperate in the Fe-mediated bioleaching system, and the ratio of these two species was regulated by biochar for enhancing the efficiency of bioleaching. Hence, this work provides a method to improve bioleaching efficiency with low-cost solid redox media. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Influence of Pitting Corrosion on Fatigue and Corrosion Fatigue of Ship and Offshore Structures, Part II: Load - Pit - Crack Interaction

    Directory of Open Access Journals (Sweden)

    Jakubowski Marek

    2015-09-01

    Full Text Available In the paper has been discussed influence of stresses on general corrosion rate and corrosion pit nucleation rate and growth , whose presence has been questioned by some authors but accepted by most of them. Influence of roughness of pit walls on fatigue life of a plate suffering pit corrosion and presence of the so called „ non-damaging” pits which never lead to initiation of fatigue crack, has been presented. Possibility of prediction of pit-to-crack transition moment by two different ways, i.e. considering a pit a stress concentrator or an equivalent crack, has been analyzed. Also, influence of statistical distribution of depth of corrosion pits as well as anticorrosion protection on fatigue and corrosion fatigue has been described.

  12. [Determination of metals in waste bag filter of steel works by microwave digestion-flame atomic absorption spectrometry].

    Science.gov (United States)

    Ning, Xun-An; Zhou, Yun; Liu, Jing-Yong; Wang, Jiang-Hui; Li, Lei; Ma, Xiao-Guo

    2011-09-01

    A method of microwave digestion technique-flame atomic absorption spectrometry was proposed to determine the total contents of Cu, Zn, Pb, Cd, Cr and Ni in five different kinds of waste bag filters from a steel plant. The digestion effects of the six acid systems on the heavy metals digestion were studied for the first time. The relative standard deviation (RSD) of the method was between 1.02% and 9.35%, and the recovery rates obtained by standard addition method ranged from 87.7% to 105.6%. The results indicated that the proposed method exhibited the advantages of simplicity, speediness, accuracy and repeatability, and it was suitable for determining the metal elements of the waste bag filter. The results also showed that different digestion systems should be used according to different waste bag filters. The waste bag filter samples from different production processes had different metal elements content. The Pb and Zn were the highest in the waste bag filters, while the Cu, Ni, Cd and Cr were relatively lower. These determination results provided the scientific data for further treatment and disposal of the waste bag filter.

  13. Function of all-metal separators for waste fuels. Phase 1; Funktion av allmetallseparatorer foer avfallsbraenslen. Etapp 1

    Energy Technology Data Exchange (ETDEWEB)

    Jacoby, Juergen; Wrangensten, Lars

    2004-08-01

    Various waste incineration facilities, which use different types of waste fuels, have difficulties with a high content of non-magnetic metal, especially aluminum in their fuels. Aluminum may melt on the grate and can lead to corrosion or fouling in the furnace. Additionally, a high content of aluminum in the flyash may cause difficulties in terms of storage or further use of the ash as e.g. construction material. The industrial demand for efficient separators for non-magnetic metals from a fuel stream is rather large. There is however some uncertainty in the performance and efficiency of metal separators. Two types of separators can be found, the first type is called eddy current separator, the other type is based upon a metal detector with a sorting unit in the form of a chute or similar afterwards. An eddy current separator consists of a fast rotating drum containing several permanent magnets with alternating polarity. Due to the rotation, the change in the magnetic field induces eddy currents in conducting materials. The eddy currents cause a force in non-magnetic metal, the Lorentz force, which repels the material away from the rotating drum while all other material follows the systems flow direction. Systems equipped with a metal detector activate a mechanical sorting device, separate chute or air nozzles, when a metal particle is detected. In contrast to eddy current separators all types of metals can be detected and sorted out by systems based on metal detector. Several technical solutions for metal separation supplied by various manufacturers are described in the report. The companies have been asked to supply product information on the working principle, technical data, efficiency and limits for different types of metals. Two reference power plants have been visited and their experiences with all-metal separators are described. Haendeloeverket in Norrkoeping uses eddy current separators for separation of non-magnetic metals from household waste

  14. INAA of toxic heavy metals in solid wastes from Indian cities

    International Nuclear Information System (INIS)

    Garg, A.N.; Ramakrishna, V.V.S.; Singh, V.

    1997-01-01

    Solid wastes and sewage sludges in metropolitan cities are potential health hazards due to toxic heavy metal pollutants. Sewage sludges from six Indian cities viz., Ahmedabad, Bikaner, Bombay, Calcutta, Jaipur, Kanpur and solid wastes from six different disposal sites of the capital city of Delhi have been analyzed for 26 elements (As, Au, Ba, Br, Co, Cr, Cs, Cu, Eu, Fe, Hg, Hf, K, La, Mg, Mn, Mo, Na, P, Rb, Sb, Sc, Se, Sr, Th and Zn) by employing instrumental neutron activation analysis (INAA). Sewage sludges from Bombay after different treatments (settled, digested, aerobic, anaerobic) along with several environmental SRMs were also analyzed. An attempt has been made to attribute the pollutant sources to the degree of urbanisation and industrialization of the city. Role of treatment processes in the removal/retention of heavy metals is discussed. (author)

  15. pitting corrosion susceptibility pitting corrosion susceptibility of aisi

    African Journals Online (AJOL)

    eobe

    2DEPARTMENT OF MECHANICAL ENGINEERING, UNIVERSITY OF BENIN, BENIN- CITY, EDO STATE, NIGERIA. E-mail addresses: ... fluids and aggressive chemicals. Pitting corrosion ... the kitchen, food manufacturing and dispensing and.

  16. Sources of heavy metal contamination in Swedish wood waste used for combustion

    International Nuclear Information System (INIS)

    Krook, J.; Martensson, A.; Eklund, M.

    2006-01-01

    In this paper, wood waste (RWW) recovered for heat production in Sweden was studied. Previous research has concluded that RWW contains elevated amounts of heavy metals, causing environmental problems during waste management. This study extends previous work on RWW by analysing which pollution sources cause this contamination. Using existing data on the metal contents in various materials, and the amounts of these materials in RWW, the share of the elevated amounts of metals in RWW that these materials explain was quantified. Six different materials occurring in RWW were studied and the results show that they explain from 70% to 100% of the amounts of arsenic, chromium, lead, copper and zinc in RWW. The most important materials contributing to contamination of RWW are surface-treated wood, industrial preservative-treated wood, plastic and galvanised fastening systems. These findings enable the development and evaluation of strategies aiming to decrease pollution and resource loss from handling RWW. It is argued that source separation and measures taken further downstream from the generation site, such as treatment, need to be combined to substantially decrease the amount of heavy metals in RWW

  17. The role of noble metals in electric melting of nuclear waste glass

    International Nuclear Information System (INIS)

    Roth, G.; Weisenburger, S.

    1990-01-01

    Electrical melting of nuclear waste glass in ceramic melters applies Joule heating, with the molten glass acting as the conductive medium. The local energy release inside the melt relieves from the restriction of external heat addition, allowing to scale up the melter to industrial units. Certainly, that principle makes the melter operation susceptible for changes of the electrical properties of the glass melt. Hence, the melt properties are required to be locally uniform and constant with time. Temporary fluctuations in the feed composition, however, are usually attenuated by the high retention times being in the order of a day and more. More essential for the melter operation are segregation effects occurring systematically. This behaviour can be observed in the case of the so-called noble metal elements Ruthenium, Palladium and Rhodium, belonging to the Platinum metal group. The subject of this paper is to describe the behaviour of the noble metals in electric melting and the problems they can contribute to. The discussion is based on detailed knowledge gained from PAMELA's LEWC processing and from large-scale vitrification of commercial-like waste simulate at INE/KfK. Finally, ways are indicated to solve the noble metal problem technically

  18. RCRA closure plan for the Bear Creek Burial Grounds B Area and Walk-In Pits at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1992-11-01

    The Bear Creek Burial Grounds (BCBG) are located on the southwest flank of Pine Ridge ∼1.5 miles west of the Oak Ridge Y-12 Plant in Bear Creek Valley. This facility consists of several contiguous disposal sites identified as Burial Grounds A, B, C, and D. Each burial site consists of a series of trenches used for disposal of solid wastes and, in some cases, liquid wastes. Initially, the RCRA Closure/Postclosure plan for the BCBG was intended to apply to A Area, C-West, B Area, and the walk-in pits for BCBG. However, a plan was provided to include the B Area in the walk-in pits so that both areas cold be closed under one cap. The closure plan for B Area and the walk-in pits is presented in this document. The actual quantity and identity of materials is uncertain. The largest volume of material disposed in BCBG consists of uranium-contaminated industrial trash (paper, wood, steel, glass, and rubble)

  19. Biogas-centred domestic waste recycling system

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, C L

    1983-04-01

    In fast developing suburban towns, there is an urgent need for an integrated system for waste recycling and energy and fertiliser supply on a single house basis. This is because even though toilet waste is handled by a septic tank-soak pit arrangement, kitchen and bathroom water and solid organic wastes have to be discharged outside the house. A biogas based domestic waste recycling system has been designed and constructed and has been successfully working. Some salient features of this plant are discussed here.

  20. Removal of heavy metals from aqueous phases using chemically modified waste Lyocell fiber

    Energy Technology Data Exchange (ETDEWEB)

    Bediako, John Kwame; Wei, Wei; Kim, Sok; Yun, Yeoung-Sang, E-mail: ysyun@jbnu.ac.kr

    2015-12-15

    Highlights: • Waste Lyocell fiber was chemically modified into cellulose xanthate. • The sorbent showed high affinity for Pb(II), Cd(II) and Cu(II) ions. • The sorbent also showed strong Cu(II) selectivity in Pb(II)–Cd(II)–Cu(II) ternary metal solutions. - Abstract: In this study, an outstanding performance of chemically modified waste Lyocell for heavy metals treatment is reported. The sorbent, which was prepared by a simple and concise method, was able to bind heavy metals such as Pb(II), Cu(II) and Cd(II), with very high efficiencies. The binding mechanisms were studied through adsorption and standard characterization tests such as scanning electron microscopy, energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction analyses. Adsorption kinetics was very fast and attained equilibrium within 5 min in all metals studied. The maximum single metal uptakes were 531.29 ± 0.28 mg/g, 505.64 ± 0.21 mg/g, and 123.08 ± 0.26 mg/g for Pb(II), Cd(II) and Cu(II), respectively. In ternary metal systems, Cu(II) selectivity was observed and the underlying factors were discussed. The sorbent by its nature, could be very effective in treating large volumes of wastewater with the contact of very little amount.

  1. What's weathering? Mineralogy and field leach studies in mine waste, Leadville and Montezuma mining districts, Colorado

    Science.gov (United States)

    Diehl, S.F.; Hageman, Phil L.; Smith, Kathleen S.

    2006-01-01

    Weathering is important in the development of rock fabrics that control porosity in mine-waste materials, and in turn, porosity affects metal transport through and from mine-waste piles into watersheds. Mine-waste piles are dynamic physical and chemical systems as evidenced by remnant Fe-oxide boxwork structures after sulfide minerals, development of alteration rinds and etch pits on grains, and precipitation of secondary minerals under low temperature conditions. These microscale changes in the mine-waste materials are the result of partial to total dissolution of sulfide and other minerals. Mine-waste materials from the Dinero, Lower Chatauqua, and Saints John sites, Leadville and Montezuma mining districts, Colorado, exhibit rock fabrics that indicate that weathering products, e.g., Fe oxyhydroxides, jarosite, and clays, have been transported in suspension through the waste piles and deposited in voids and as coatings on rock fragments. Microscale characterization of weathered, partially dissolved minerals lends insight into the source of leachable metals in these mine-waste sites. Mineralogic studies show that galena in the Lower Chatauqua waste is enriched in Ag. Qualitative and semiquantitative microanalysis of weathered, altered galena grains from all three sites show that the Ag-bearing galena is more susceptible to dissolution. It is not surprising, then, that solutions experimentally leached from Lower Chatauqua waste are higher in Pb (2310 ppb) compared to leachates from the Dinero (31 ppb) and Saints John (1360 ppb) wastes. The mobility of metals is increased at acidic pH. Using the USGS Field Leach Test protocol, leachate derived from the Dinero waste has a pH of 3 and high concentrations of Al (443 ppb), Fe (441 ppb), and Zn (7970 ppb). Leachate from Sts. John tailings has a pH about 4 and high concentrations of Mn (1520 ppb), Zn (2240 ppb), and Pb (1360 ppb). Leachate from the Lower Chatauqua waste has an intermediate pH of 5, but in addition to the

  2. Analysis of physical composition and heavy metals pollution of municipal solid waste (MSW) in Beijing

    Science.gov (United States)

    Zhang, H. B.; Zhang, H. Y.; Wang, G. Q.; Bai, X. J.

    2018-03-01

    By using on-site sampling and physical-chemical analysis, the physical composition and the contents of heavy metals in Beijing MSW were researched. The result showed that the main components of MSW in Beijing are mainly kitchen waste, the average content of kitchen waste are more than 60% and 50% in summer and in winter, respectively. The pollution of Cu, Hg and Cr are all more serious for MSW in Haidian and Dongcheng district. The heavy metal pollution of MSW in summer is higher than that in winter in Beijing. Seasonal impacts should be taken into consideration when dealing with MSW. The content of heavy metals in MSW exceeded the background value of soil in Haidian and Dongcheng districts. In order to reduce heavy metal pollution, the MSW should be separated collection and treated.

  3. Environmental assessments for the existing radioactive materials in the Weldon Spring raffinate pits

    International Nuclear Information System (INIS)

    Yang, J.Y.; Wang, J.

    1985-01-01

    Various radioactive residues (raffinates) and wastes from the processing of uranium and thorium between 1957 and 1966 are stored in four pits at Weldon Spring, Missouri. The US Department of Energy (DOE) plans to stabilize all the contaminated materials on a long-term (more than 1000-year) basis. The effectiveness of stabilization measures are evaluated by estimating radioactive releases under two options: (1) no action, and (2) improved containment using the existing raffinate pits. Two major pathways of radiation exposure are examined: (1) airborne radioactive gases and particulates, and (2) seepage into near-surface groundwater. The relative reductions of releases into the air and groundwater for a reference stabilization option (improved containment) are analyzed using mathematical models for radioactive and particulate gas fluxes and atmospheric dispersion, as well as groundwaterr transport and dispersion. The consequent health risks for nearby individuals and the general public are also evaluated. This study focuses on the migration of radionuclides under existing conditions and evaluates the effectiveness of proposed stabilization measures at the pits. Results indicate that the potential effects to the general public would be insignificant. 22 refs., 2 figs., 6 tabs

  4. Scoping evaluation of the technical capabilities of DOE sites for disposal of hazardous metals in mixed low-level waste

    International Nuclear Information System (INIS)

    Gruebel, M.M.; Waters, R.D.; Langkopf, B.S.

    1997-05-01

    A team of analysts designed and conducted a scoping evaluation to estimate the technical capabilities of fifteen Department of Energy sites for disposal of the hazardous metals in mixed low-level waste (i.e., waste that contains both low-level radioactive materials and hazardous constituents). Eight hazardous metals were evaluated: arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver. The analysis considered transport only through the groundwater pathway. The results are reported as site-specific estimates of maximum concentrations of each hazardous metal in treated mixed low-level waste that do not exceed the performance measures established for the analysis. Also reported are site-specific estimates of travel times of each hazardous metal to the point of compliance

  5. Precious metal recovery from waste printed circuit boards using cyanide and non-cyanide lixiviants--A review.

    Science.gov (United States)

    Akcil, Ata; Erust, Ceren; Gahan, Chandra Sekhar; Ozgun, Mehmet; Sahin, Merve; Tuncuk, Aysenur

    2015-11-01

    Waste generated by the electrical and electronic devices is huge concern worldwide. With decreasing life cycle of most electronic devices and unavailability of the suitable recycling technologies it is expected to have huge electronic and electrical wastes to be generated in the coming years. The environmental threats caused by the disposal and incineration of electronic waste starting from the atmosphere to the aquatic and terrestrial living system have raised high alerts and concerns on the gases produced (dioxins, furans, polybrominated organic pollutants, and polycyclic aromatic hydrocarbons) by thermal treatments and can cause serious health problems if the flue gas cleaning systems are not developed and implemented. Apart from that there can be also dissolution of heavy metals released to the ground water from the landfill sites. As all these electronic and electrical waste do posses richness in the metal values it would be worth recovering the metal content and protect the environmental from the pollution. Cyanide leaching has been a successful technology worldwide for the recovery of precious metals (especially Au and Ag) from ores/concentrates/waste materials. Nevertheless, cyanide is always preferred over others because of its potential to deliver high recovery with a cheaper cost. Cyanidation process also increases the additional work of effluent treatment prior to disposal. Several non-cyanide leaching processes have been developed considering toxic nature and handling problems of cyanide with non-toxic lixiviants such as thiourea, thiosulphate, aqua regia and iodine. Therefore, several recycling technologies have been developed using cyanide or non-cyanide leaching methods to recover precious and valuable metals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Determination of Heavy Metal Levels in Various Industrial Waste Waters

    Directory of Open Access Journals (Sweden)

    Mustafa Şahin Dündar

    2012-06-01

    Full Text Available Important part of the environmetal pollution consists of waste water and water pollution. The water polluted by anthropogenical, industrial, and agricultural originated sources are defined as waste waters which are the main pollution sources for reservoirs, rivers, lakes, and seas. In this work, waste waters of leather, textile, automotive side, and metal plating industries were used to determine the levels of Cu, Zn, Cr, Pb and Ni by using Flame Atomic Absorption Spectrometer. As a result, highest mean levels of copper in supernatants of plating and textile industries were observed as 377,18 ng ml-1, respectively 103 ng ml-1 lead and 963,6 ng ml-1 nickel in plating industry, 1068,2 ng ml-1 zinc and 14557,1 ng ml-1 chromium in plating and leather industries were determined.

  7. Species redistribution during solidification of nuclear fuel waste metal castings

    Energy Technology Data Exchange (ETDEWEB)

    Naterer, G F; Schneider, G E [Waterloo Univ., ON (Canada)

    1994-12-31

    An enthalpy-based finite element model and a binary system species redistribution model are developed and applied to problems associated with solidification of nuclear fuel waste metal castings. Minimal casting defects such as inhomogeneous solute segregation and cracks are required to prevent container corrosion and radionuclide release. The control-volume-based model accounts for equilibrium solidification for low cooling rates and negligible solid state diffusion for high cooling rates as well as intermediate conditions. Test problems involving nuclear fuel waste castings are investigated and correct limiting cases of species redistribution are observed. (author). 11 refs., 1 tab., 13 figs.

  8. Oxygen pitting failure of a bagasse boiler tube

    CSIR Research Space (South Africa)

    Heyes, AM

    2001-04-01

    Full Text Available Examination of a failed roof tube from a bagasse boiler showed transverse through-cracks and extensive pitting. The pitting was typically oxygen induced pitting and numerous fatigue cracks had started within these pits. It is highly probable...

  9. Accountability Quality Shuffler Measurements on Pits

    International Nuclear Information System (INIS)

    Rinard, P.M.

    2000-01-01

    Pits have generally been treated as accountable units that are intact if merely present and they are excluded from the more demanding nondestructive assay requirements. As pits begin to flow into disposition streams, there may be more incentive to measure the masses of their fissile components for accountability purposes. This Department of Energy Office of Safeguards and Security (OSS) Lifecycle Project has explored some ways in which such measurements may be done successfully. The active neutron instrument called a shuffler has been used to measure a variety of actual pits, and a calculational technique has been developed to accurately predict such count rates. Passive multiplicity counting has previously been applied to pits for determining their plutonium contents. This combination of measurement and calculational techniques provide powerful and accurate tools for determining the fissile contents of pits with the quality needed for accountability purposes

  10. Selective removal/recovery of RCRA metals from waste and process solutions using polymer filtration trademark technology

    International Nuclear Information System (INIS)

    Smith, B.F.

    1997-01-01

    Resource Conservation and Recovery Act (RCRA) metals are found in a number of process and waste streams at many DOE, U.S. Department of Defense, and industrial facilities. RCRA metals consist principally of chromium, mercury, cadmium, lead, and silver. Arsenic and selenium, which form oxyanions, are also considered RCRA elements. Discharge limits for each of these metals are based on toxicity and dictated by state and federal regulations (e.g., drinking water, RCRA, etc.). RCRA metals are used in many current operations, are generated in decontamination and decommissioning (D ampersand D) operations, and are also present in old process wastes that require treatment and stabilization. These metals can exist in solutions, as part of sludges, or as contaminants on soils or solid surfaces, as individual metals or as mixtures with other metals, mixtures with radioactive metals such as actinides (defined as mixed waste), or as mixtures with a variety of inert metals such as calcium and sodium. The authors have successfully completed a preliminary proof-of-principle evaluation of Polymer Filtration trademark (PF) technology for the dissolution of metallic mercury and have also shown that they can remove and concentrate RCRA metals from dilute solutions for a variety of aqueous solution types using PF technology. Another application successfully demonstrated is the dilute metal removal of americium and plutonium from process streams. This application was used to remove the total alpha contamination to below 30 pCi/L for the wastewater treatment plant at TA-50 at Los Alamos National Laboratory (LANL) and from nitric acid distillate in the acid recovery process at TA-55, the Plutonium Facility at LANL (ESP-CP TTP AL16C322). This project will develop and optimize the PF technology for specific DOE process streams containing RCRA metals and coordinate it with the needs of the commercial sector to ensure that technology transfer occurs

  11. Selective removal/recovery of RCRA metals from waste and process solutions using polymer filtration{trademark} technology

    Energy Technology Data Exchange (ETDEWEB)

    Smith, B.F. [Los Alamos National Lab., NM (United States)

    1997-10-01

    Resource Conservation and Recovery Act (RCRA) metals are found in a number of process and waste streams at many DOE, U.S. Department of Defense, and industrial facilities. RCRA metals consist principally of chromium, mercury, cadmium, lead, and silver. Arsenic and selenium, which form oxyanions, are also considered RCRA elements. Discharge limits for each of these metals are based on toxicity and dictated by state and federal regulations (e.g., drinking water, RCRA, etc.). RCRA metals are used in many current operations, are generated in decontamination and decommissioning (D&D) operations, and are also present in old process wastes that require treatment and stabilization. These metals can exist in solutions, as part of sludges, or as contaminants on soils or solid surfaces, as individual metals or as mixtures with other metals, mixtures with radioactive metals such as actinides (defined as mixed waste), or as mixtures with a variety of inert metals such as calcium and sodium. The authors have successfully completed a preliminary proof-of-principle evaluation of Polymer Filtration{trademark} (PF) technology for the dissolution of metallic mercury and have also shown that they can remove and concentrate RCRA metals from dilute solutions for a variety of aqueous solution types using PF technology. Another application successfully demonstrated is the dilute metal removal of americium and plutonium from process streams. This application was used to remove the total alpha contamination to below 30 pCi/L for the wastewater treatment plant at TA-50 at Los Alamos National Laboratory (LANL) and from nitric acid distillate in the acid recovery process at TA-55, the Plutonium Facility at LANL (ESP-CP TTP AL16C322). This project will develop and optimize the PF technology for specific DOE process streams containing RCRA metals and coordinate it with the needs of the commercial sector to ensure that technology transfer occurs.

  12. In situ technology evaluation and functional and operational guidelines for treatability studies at the radioactive waste management complex at the Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Hyde, R.A.; Donehey, A.J.; Piper, R.B.; Roy, M.W.; Rubert, A.L.; Walker, S.

    1991-07-01

    The purpose of this document is to provide EG ampersand G Idaho's Waste Technology Development Department with a basis for selection of in situ technologies for demonstration at the Radioactive Waste Management Complex (RWMC) of the Idaho National Engineering Laboratory (INEL) and to provide information for Feasibility Studies to be performed according to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). The demonstrations will aid in meeting Environmental Restoration/Waste Management (ER/WM) schedules for remediation of waste at Waste Area Group (WAG) 7. This report is organized in six sections. Section 1, summarizes background information on the sites to be remediated at WAG-7, specifically, the acid pit, soil vaults, and low-level pits and trenches. Section 2 discusses the identification and screening of in situ buried waste remediation technologies for these sites. Section 3 outlines the design requirements. Section 4 discusses the schedule [in accordance with Buried Waste Integrated Demonstration (BWID) scoping]. Section 5 includes recommendations for the acid pit, soil vaults, and low-level pits and trenches. A listing of references used to compile the report is given in Section 6. Detailed technology information is included in the Appendix section of this report

  13. Operation for Rokkasho Low Level Radioactive Waste Disposal Center

    International Nuclear Information System (INIS)

    Kamizono, Hideki

    2008-01-01

    The Rokkasho Low Level Radioactive Waste (LLW) Disposal Center is located in Oishitai, Rokkasho-mura, Kamikitagun, of Aomori Prefecture. This district is situated in the southern part of Shimohita Peninsula in the northeastern corner of the prefecture, which lies at the northern tip of Honshu, Japan's main island. The Rokkasho LLW Disposal Center deals with only LLW generated by operating of nuclear power plants. The No.1 and No.2 disposal facility are now in operation. The disposal facilities in operation have a total dispose capacity of 80,000m 3 (equivalent to 400,000 drums). Our final business scope is to dispose of radioactive waste corresponding to 600,000 m 3 (equivalent to 3000,000 drums). For No.1 disposal facility, we have been disposing of homogeneous waste, including condensed liquid waste, spent resin, solidified with cement and asphalt, etc. For No.2 disposal facility, we can bury a solid waste solidified with mortar, such as activated metals and plastics, etc. Using an improved construction technology for an artificial barrier, the concrete pits in No.2 disposal facility could be constructed more economical and spacious than that of No.1. Both No.1 and No.2 facility will be able to bury about 200,000 waste packages (drums) each corresponding to 40,000 m 3 . As of March 17, 2008, Approximately 200,00 waste drums summing up No.1 and No.2 disposal facility have been received from Nuclear power plants and buried. (author)

  14. Storage facility for radioactive wastes

    International Nuclear Information System (INIS)

    Okada, Kyo

    1998-01-01

    Canisters containing high level radioactive wastes are sealed in overpacks in a receiving building constructed on the ground. A plurality of storage pits are formed in a layered manner vertically in multi-stages in deep underground just beneath the receiving building, for example underground of about 1000m from the ground surface. Each of the storage pits is in communication with a shaft which vertically communicates the receiving building and the storage pits, and is extended plainly in a horizontal direction from the shaft. The storage pit comprises an overpack receiving chamber, a main gallery and a plurality of galleries. A plurality of holes for burying the overpacks are formed on the bottom of the galleries in the longitudinal direction of the galleries. A plurality of overpack-positioning devices which run in the main gallery and the galleries by remote operation are disposed in the main gallery and the galleries. (I.N.)

  15. Selective chelation-supercritical fluid extraction of metal ions from waste materials

    International Nuclear Information System (INIS)

    Wai, C.N.; Laintz, K.E.; Yonker, C.R.

    1993-01-01

    The removal of toxic organics, metals, and radioisotopes from solids or liquids is a major concern in the treatment of industrial and nuclear wastes. For this reason, developing methods for selective separation of toxic metals and radioactive materials from solutions of complex matrix is an important problem in environmental research. Recent developments indicate supercritical fluids are good solvents for organic compounds. Many gases become supercritical fluids under moderate temperatures and pressures. For example, the critical temperature and pressure of carbon dioxide are 31 degrees C and 73 atm, respectively. The high diffusivity, low viscosity, and T-P dependence of solvent strength are some attractive properties of supercritical fluid extraction (SFE). Since CO 2 offers the additional benefits of stability and non-toxicity, the SFE technique avoids generation of organic liquid waste and exposure of personnel to toxic solvents. While direct extraction of metal ions by supercritical fluids is highly inefficient, these ions when complexed with organic ligands become quite soluble in supercritical fluids. Specific ligands can be used to achieve selective extraction of metal ions in this process. After SFE, the fluid phase can be depressurized for precipitation of the metal chelates and recycled. The ligand can also be regenerated for repeated use. The success of this selective chelation-supercritical fluid extraction (SC-SFE) process depends on a number of factors including the efficiencies of the selective chelating agents, solubilities of metal chelates in supercritical fluids, rate of extraction, ease of regeneration of the ligands, etc. In this report, the authors present recent results on the studies of the solubilities of metal chelates in supercritical CO 2 , experimental ions from aqueous solution, and the development of selective chelating agents (ionizable crown ethers) for the extraction of lanthanides and actinides

  16. Record of Decision Remedial Alternative Selection for the D-Area Burning/Rubble Pits (431-D and 431-1D)

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, E.R. [Westinghouse Savannah River Company, AIKEN, SC (United States); Mason, J.T.

    1997-02-01

    The D-Area Burning/Rubble Pits (DBRP) (431-D and 431-1D) Waste Unit is listed as a Resource Conservation and Recovery Act (RCRA) 3004(U) Solid Waste Management Unit/Comprehensive Environmental Response Compensation and Liability Act (CERCLA) unit in Appendix C of the Federal Facility Agreement (FFA) for the Savannah River Site (SRS). This decision document presents the selected remedial alternative for the DBRP located at the SRS in Aiken, South Carolina.

  17. Evaluation of physical, chemical and heavy metal concentration of food waste composting

    Directory of Open Access Journals (Sweden)

    Abdul Kadir Aeslina

    2017-01-01

    Full Text Available In this study, food waste composting with rice husk and coconut fibre as compost medium were carried out. Two types of different fermentation liquids were prepared which were fermented liquid (banana peel and fermented liquid from fermented soybeans. During the composting process, a compost samples for a twenty week duration at an interval time of two weeks. Among the physico-chemical parameters that were tested were temperature, moisture content, pH value, Total Nitrogen, Total Phosphorous, Potassium and Total Organic Carbon and Carbon Nitrogen ratio. Heavy metals such as copper, cadmium, lead, nickel and arsenic were observed and analysed. From this study, it was found that, the temperature increased during the thermophilic phase while there was gradually increase of Total Nitrogen, Total Phosphorous and Potassium from the beginning till the end of the composting process. It was also found that the total organic carbon (TOC and the carbon nitrogen ratio decreased significantly during the decomposition process. Traces amounts of heavy metals were also detected and remains below the standard Malaysian Environmental regulations. It was concluded that, the composting process was faster with processed food waste followed by combination of processed food waste and raw. Raw food waste were demonstrated the lowest degradation rate.

  18. Activation of aluminum as an effective reducing agent by pitting corrosion for wet-chemical synthesis.

    Science.gov (United States)

    Li, Wei; Cochell, Thomas; Manthiram, Arumugam

    2013-01-01

    Metallic aluminum (Al) is of interest as a reducing agent because of its low standard reduction potential. However, its surface is invariably covered with a dense aluminum oxide film, which prevents its effective use as a reducing agent in wet-chemical synthesis. Pitting corrosion, known as an undesired reaction destroying Al and is enhanced by anions such as F⁻, Cl⁻, and Br⁻ in aqueous solutions, is applied here for the first time to activate Al as a reducing agent for wet-chemical synthesis of a diverse array of metals and alloys. Specifically, we demonstrate the synthesis of highly dispersed palladium nanoparticles on carbon black with stabilizers and the intermetallic Cu₂Sb/C, which are promising candidates, respectively, for fuel cell catalysts and lithium-ion battery anodes. Atomic hydrogen, an intermediate during the pitting corrosion of Al in protonic solvents (e.g., water and ethylene glycol), is validated as the actual reducing agent.

  19. Sedimentary modelling and nuclear-waste disposal

    International Nuclear Information System (INIS)

    Van Loon, A.J.

    1982-01-01

    Nuclear energy is an important source of energy. Recently a slow down is experienced in its growth rate, due to the following factors: a) the supposed shortage of uranium; b) the fear for the consequences of nuclear accident, and c) the problem of nuclear wastes. Two types of waste are distinguished: a) fission products and actinides, and b) operational waste. The United States have started a program that must lead in 1989 to the first final storage of such waste in salt. Open-pit mines and oil-well drilling are discussed as possible solutions for operational waste storage

  20. Effects of cold working on the pitting corrosion behavior s of AISI 304 stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kee Min; Kim, Jong Soo; Kim, Young Jun; Kwon, Houk Sang [KAIST, Daejon (Korea, Republic of)

    2015-12-15

    These microstructural changes by cold working can lead improvement of mechanical properties, however from a corrosion resistant point of view, the effects of cold working on the corrosion resistance of stainless steel have been argued. Several studies has been focused on the influence of cold working on the localized corrosion resistance of stainless steels. However, the opinions about the role of cold working on the localized corrosion resistance are highly in consistence. Some studies report that the pitting potential of austenitic stainless steels decreased with cold working level, on the other hands, other studies claimed that the pitting resistance was increased by cold working. Therefore it is necessary to verify how cold working affects pitting corrosion behavior of austenitic stainless steels. In the present work, the influence of cold working on the localized corrosion of AISI 304stainless steel in the neutral chloride solution was studied based on point defect model (PDM). The fraction of deformation-induced martensite was linearly increased with cold rolling level. Through cold rolling, the pitting potential was decreased, the metastable pitting event density was significantly increased and the repassivation potential was decreased. The overall localized corrosion resistance was decreased with cold working, however cold working level increased from 30 % to 50 %, localized corrosion resistance was recovered. The accumulated cation vacancy generates a void at metal/film interface, therefore film breakdown accelerates for cold worked alloys.

  1. Effects of cold working on the pitting corrosion behavior s of AISI 304 stainless steels

    International Nuclear Information System (INIS)

    Jung, Kee Min; Kim, Jong Soo; Kim, Young Jun; Kwon, Houk Sang

    2015-01-01

    These microstructural changes by cold working can lead improvement of mechanical properties, however from a corrosion resistant point of view, the effects of cold working on the corrosion resistance of stainless steel have been argued. Several studies has been focused on the influence of cold working on the localized corrosion resistance of stainless steels. However, the opinions about the role of cold working on the localized corrosion resistance are highly in consistence. Some studies report that the pitting potential of austenitic stainless steels decreased with cold working level, on the other hands, other studies claimed that the pitting resistance was increased by cold working. Therefore it is necessary to verify how cold working affects pitting corrosion behavior of austenitic stainless steels. In the present work, the influence of cold working on the localized corrosion of AISI 304stainless steel in the neutral chloride solution was studied based on point defect model (PDM). The fraction of deformation-induced martensite was linearly increased with cold rolling level. Through cold rolling, the pitting potential was decreased, the metastable pitting event density was significantly increased and the repassivation potential was decreased. The overall localized corrosion resistance was decreased with cold working, however cold working level increased from 30 % to 50 %, localized corrosion resistance was recovered. The accumulated cation vacancy generates a void at metal/film interface, therefore film breakdown accelerates for cold worked alloys

  2. Inhibition of acid mine drainage and immobilization of heavy metals from copper flotation tailings using a marble cutting waste

    Science.gov (United States)

    Tozsin, Gulsen

    2016-01-01

    Acid mine drainage (AMD) with high concentrations of sulfates and metals is generated by the oxidation of sulfide bearing wastes. CaCO3-rich marble cutting waste is a residual material produced by the cutting and polishing of marble stone. In this study, the feasibility of using the marble cutting waste as an acid-neutralizing agent to inhibit AMD and immobilize heavy metals from copper flotation tailings (sulfide- bearing wastes) was investigated. Continuous-stirring shake-flask tests were conducted for 40 d, and the pH value, sulfate content, and dissolved metal content of the leachate were analyzed every 10 d to determine the effectiveness of the marble cutting waste as an acid neutralizer. For comparison, CaCO3 was also used as a neutralizing agent. The average pH value of the leachate was 2.1 at the beginning of the experiment ( t = 0). In the experiment employing the marble cutting waste, the pH value of the leachate changed from 6.5 to 7.8, and the sulfate and iron concentrations decreased from 4558 to 838 mg/L and from 536 to 0.01 mg/L, respectively, after 40 d. The marble cutting waste also removed more than 80wt% of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) from AMD generated by copper flotation tailings.

  3. Assessing metal contamination from construction and demolition (C&D) waste used to infill wetlands: using Deroceras reticulatum (Mollusca: Gastropoda).

    Science.gov (United States)

    Staunton, John A; Mc Donnell, Rory J; Gormally, Michael J; Williams, Chris D; Henry, Tiernan; Morrison, Liam

    2014-11-01

    Large quantities of construction and demolition waste (C&D) are produced globally every year, with little known about potential environmental impacts. In the present study, the slug, Deroceras reticulatum (Mollusca: Gastropoda) was used as the first biomonitor of metals (Ag, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Ti, Tl, V and Zn) on wetlands post infilling with construction and demolition (C&D) waste. The bioaccumulation of As, Ba, Cd, Co, Sb, Se and Tl were found to be significantly elevated in slugs collected on C&D waste when compared to unimproved pastures (control sites), while Mo, Se and Sr had significantly higher concentrations in slugs collected on C&D waste when compared to known contaminated sites (mining locations), indicating the potential hazardous nature of C&D waste to biota. Identifying exact sources for these metals within the waste can be problematic, due to its heterogenic nature. Biomonitors are a useful tool for future monitoring and impact studies, facilitating policy makers and regulations in other countries regarding C&D waste infill. In addition, improving separation of C&D waste to allow increased reuse and recycling is likely to be effective in reducing the volume of waste being used as infill, subsequently decreasing potential metal contamination.

  4. Development of Ceramic Coating on Metal Substrate using Industrial Waste and Ore Minerals

    Science.gov (United States)

    Bhuyan, S. K.; Thiyagarajan, T. K.; Mishra, S. C.

    2017-02-01

    The technological advancement in modern era has a boon for enlightening human life; but also is a bane to produce a huge amount of (industrial) wastes, which is of great concern for utilization and not to create environmental threats viz. polution etc. In the present piece of research work, attempts have been made to utilize fly ash (wastes of thermal power plants) and along with alumina bearing ore i.e. bauxite, for developing plasma spray ceramic coatings on metals. Fly ash and with 10 and 20% bauxite addition is used to deposit plasma spray coatings on a metal substrate. The surface morphology of the coatings deposited at different power levels of plasma spraying investigated through SEM and EDS analysis. The coating thickness is measured. The porosity levels of the coatings are evaluated. The coating hardness isalso measured. This piece of research work will be beneficial for future development and use of industrial waste and ore minerals for high-valued applications.

  5. Application of fuel cell for pyrite and heavy metal containing mining waste

    Science.gov (United States)

    Keum, H.; Ju, W. J.; Jho, E. H.; Nam, K.

    2015-12-01

    Once pyrite and heavy metal containing mining waste reacts with water and air it produces acid mine drainage (AMD) and leads to the other environmental problems such as contamination of surrounding soils. Pyrite is the major source of AMD and it can be controlled using a biological-electrochemical dissolution method. By enhancing the dissolution of pyrite using fuel cell technology, not only mining waste be beneficially utilized but also be treated at the same time by. As pyrite-containing mining waste is oxidized in the anode of the fuel cell, electrons and protons are generated, and electrons moves through an external load to cathode reducing oxygen to water while protons migrate to cathode through a proton exchange membrane. Iron-oxidizing bacteria such as Acidithiobacillus ferrooxidans, which can utilize Fe as an electron donor promotes pyrite dissolution and hence enhances electrochemical dissolution of pyrite from mining waste. In this study mining waste from a zinc mine in Korea containing 17 wt% pyrite and 9% As was utilized as a fuel for the fuel cell inoculated with A. ferrooxidans. Electrochemically dissolved As content and chemically dissolved As content was compared. With the initial pH of 3.5 at 23℃, the dissolved As concentration increased (from 4.0 to 13 mg/L after 20 d) in the fuel cell, while it kept decreased in the chemical reactor (from 12 to 0.43 mg/L after 20 d). The fuel cell produced 0.09 V of open circuit voltage with the maximum power density of 0.84 mW/m2. Dissolution of As from mining waste was enhanced through electrochemical reaction. Application of fuel cell technology is a novel treatment method for pyrite and heavy metals containing mining waste, and this method is beneficial for mining environment as well as local community of mining areas.

  6. Metal mobilization from metallurgical wastes by soil organic acids.

    Science.gov (United States)

    Potysz, Anna; Grybos, Malgorzata; Kierczak, Jakub; Guibaud, Gilles; Fondaneche, Patrice; Lens, Piet N L; van Hullebusch, Eric D

    2017-07-01

    Three types of Cu-slags differing in chemical and mineralogical composition (historical, shaft furnace, and granulated slags) and a matte from a lead recovery process were studied with respect to their susceptibility to release Cu, Zn and Pb upon exposure to organic acids commonly encountered in soil environments. Leaching experiments (24-960 h) were conducted with: i) humic acid (20 mg/L) at pH t 0  = 4.4, ii) fulvic acid (20 mg/L) at pH t 0  = 4.4, iii) an artificial root exudates (ARE) (17.4 g/L) solution at pH t 0  = 4.4, iv) ARE solution at pH t 0  = 2.9 and v) ultrapure water (pH t 0  = 5.6). The results demonstrated that the ARE contribute the most to the mobilization of metals from all the wastes analyzed, regardless of the initial pH of the solution. For example, up to 14%, 30%, 24% and 5% of Cu is released within 960 h from historical, shaft furnace, granulated slags and lead matte, respectively, when exposed to the artificial root exudates solution (pH 2.9). Humic and fulvic acids were found to have a higher impact on granulated and shaft furnace slags as compared to the ultrapure water control and increased the release of metals by a factor up to 37.5 (Pb) and 20.5 (Cu) for granulated and shaft furnace slags, respectively. Humic and fulvic acids amplified the mobilization of metals by a maximal factor of 13.6 (Pb) and 12.1 (Pb) for historical slag and lead matte, respectively. The studied organic compounds contributed to different release rates of metallic contaminants from individual metallurgical wastes under the conditions tested. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Design of an innovative, ecological portable waste compressor for in-house recycling of paper, plastic and metal packaging waste.

    Science.gov (United States)

    Xevgenos, D; Athanasopoulos, N; Kostazos, P K; Manolakos, D E; Moustakas, K; Malamis, D; Loizidou, M

    2015-05-01

    Waste management in Greece relies heavily on unsustainable waste practices (mainly landfills and in certain cases uncontrolled dumping of untreated waste). Even though major improvements have been achieved in the recycling of municipal solid waste during recent years, there are some barriers that hinder the achievement of high recycling rates. Source separation of municipal solid waste has been recognised as a promising solution to produce high-quality recycled materials that can be easily directed to secondary materials markets. This article presents an innovative miniature waste separator/compressor that has been designed and developed for the source separation of municipal solid waste at a household level. The design of the system is in line with the Waste Framework Directive (2008/98/EC), since it allows for the separate collection (and compression) of municipal solid waste, namely: plastic (polyethylene terephthalate and high-density polyethylene), paper (cardboard and Tetrapak) and metal (aluminium and tin cans). It has been designed through the use of suitable software tools (LS-DYNA, INVENTROR and COMSOL). The results from the simulations, as well as the whole design process and philosophy, are discussed in this article. © The Author(s) 2015.

  8. Case studies of corrosion of mixed waste and transuranic waste drums

    International Nuclear Information System (INIS)

    Kosiewicz, S.T.

    1993-01-01

    This paper presents three case studies of corrosion of waste drums at the Los Alamos National Laboratory (LANL). Corrosion was not anticipated by the waste generators, but occurred because of subtle chemical or physical mechanisms. In one case, drums of a cemented transuranic (TRU) sludge experienced general and pitting corrosion. In the second instance, a chemical from a commercial paint stripper migrated from its primary containment drums to chemically attack overpack drums made of mild carbon steel. In the third case, drums of mixed low level waste (MLLW) soil corroded drum packaging even though the waste appeared to be dry when it was placed in the drums. These case studies are jointly discussed as ''lessons learned'' to enhance awareness of subtle mechanisms that can contribute to the corrosion of radioactive waste drums during interim storage

  9. Experimental Stress Analysis at Railway Inspection Pit

    Directory of Open Access Journals (Sweden)

    Nicuşor Laurentiu Zaharia

    2008-10-01

    Full Text Available Railway inspection pits are used in railway halls. The purpose of inspection pits is to allow the working under the vehicle. Inspection pits can be found in locomotive depots, factories etc. The new design for a inspection pit in a railway hall involve tests in purpose of homologations the railway infrastructure. Before the homologation committee meeting, tests are made; after the test, a testing report is made which it will be part at homologation documents.

  10. Materials testing for in situ stabilization treatability study of INEEL mixed wastes soils

    International Nuclear Information System (INIS)

    Heiser, J.; Fuhrmann, M.

    1997-09-01

    This report describes the contaminant-specific materials testing phase of the In Situ Stabilization Comprehensive Environment Response, Compensation, and Liability Act (CERCLA) Treatability Study (TS). The purpose of materials testing is to measure the effectiveness of grouting agents to stabilize Idaho National Engineering and Environmental Laboratory (INEEL) Acid Pit soils and select a grout material for use in the Cold Test Demonstration and Acid Pit Stabilization Treatability Study within the Subsurface Disposal Area (SDA) at the Radioactive Waste Management Complex (RWMC). Test results will assist the selecting a grout material for the follow-on demonstrations described in Test Plan for the Cold Test Demonstration and Acid Pit Stabilization Phases of the In Situ Stabilization Treatability Study at the Radioactive Waste Management Complex

  11. The effects of passivation parameters on pitting potential of biomedical stainless steel

    Directory of Open Access Journals (Sweden)

    Petković Dušan Lj.

    2017-01-01

    Full Text Available Passivation is a chemical process in which the electrochemical condition of passivity is gained on the surface of metal alloys. Biomedical AISI 316LVM stainless steel (SS can be passivized by means of nitric acid immersion in order to improve a protective oxide layer on the surface and consequently increase corrosion resistance of the SS in the physiological solutions. In this study, multiple regression analysis and artificial neural network (ANN were employed for mathematical modeling of the AISI 316LVM SS passivation process after immersion in the nitric acid solution. The pitting potential, which represents the mea-sure of pitting corrosion resistance, was chosen as the response, while the passivation parameters were nitric acid concentration, temperature and passivation time. The comparison between experimental results and models predictions showed that only the ANN model provided statistically accurate predictions with a high coefficient of determination and a low mean relative error. Finally, based on the derived ANN equation, the effects of the passivation parameters on pitting potential were examined. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. ON174004 and Grant no. TR35034

  12. Pits on Ascraeus

    Science.gov (United States)

    2005-01-01

    24 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows collapse pits and troughs on the lower northeast flank of the giant martian volcano, Ascraeus Mons. Layers of volcanic rock are evident in some of the pit and valley walls, and boulders the size of houses and trucks that were liberated from these walls by gravity can be seen on the floors of the depressions. Location near: 13.6oN, 102.6oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

  13. Separation and Extraction of Some Heavy and Toxic Metal Ions from Their Wastes by Ionic Membranes

    International Nuclear Information System (INIS)

    El-Sayed Hegazy, A.; Kamal, H.; Mahmoud, Gh. A.; Khalifa, N.A.

    1999-01-01

    Preparation and characterisation of a series of ion-exchange membranes for the purpose of separation and extraction of some heavy and toxic metal ions from their wastes have been studied. Such ion exchange membranes prepared by γ-radiation grafting of acrylonitrile (AN) and vinyl acetate (VAc) in a binary monomers mixture onto low density polyethylene (LDPE) using direct technique of grafting. The reaction conditions at which grafting process proceeds successfully have been determined. Many modification treatments have been attempted for the prepared membranes to improve their ion-exchange properties. The possibility of their practical use in waste water treatment from some heavy and toxic metal ions such as Pb 2+ , Cd 2+ ,Cu 2+ ,Fe 3+ ,Sr 2+ and Li + have been investigated. These grafted membranes showed great promise for its use in the field of extraction and removal of some heavy and toxic metals from their wastes

  14. Superfund Record of Decision (EPA Region 7): Weldon Spring Quarry/Plant/Pits (USDOE), Weldon Spring, MO. (Second remedial action), September 1990

    International Nuclear Information System (INIS)

    1990-01-01

    The 226-acre Weldon Spring Quarry/Plant/Pits (USDOE) site is a former ordnance works and chemical plant near the city of Weldon Spring in St. Charles County, Missouri. The site is divided into two noncontiguous areas: a 217-acre chemical plant area, comprised of various buildings, ponds and four raffinate pits, and a 9-acre quarry, which forms a valley wall at the edge of the Missouri River floodplain. Since the early 1940s, the site has been used by various government agencies for chemical and ordnance processing with chemical and radioactive waste disposal in the quarry. From 1941 to 1946, the site was an Army ordnance works used for the production of trinitrotoluene (TNT) and dinitrotoluene (DNT) explosives. The selected interim remedial action for the site includes excavating an estimated 95,000 cubic yards of chemically and radioactively contaminated bulk wastes from the quarry and temporarily storing the wastes onsite in the chemical plant area; and implementing site access restrictions. The estimated total cost for the remedial action is $11,000,000

  15. Change of heavy metal speciation, mobility, bioavailability, and ecological risk during potassium ferrate treatment of waste-activated sludge.

    Science.gov (United States)

    Yu, Ming; Zhang, Jian; Tian, Yu

    2018-05-01

    The effects of potassium ferrate treatment on the heavy metal concentrations, speciation, mobility, bioavailability, and environmental risk in waste-activated sludge (WAS) at various dosages of potassium ferrate and different treatment times were investigated. Results showed that the total concentrations of all metals (except Cd) were decreased slightly after treatment and the order of metal concentrations in WAS and treated waste-activated sludge (TWAS) was Mg > Zn > Cu > Cr > Pb > Ni > Cd. Most heavy metals in WAS remained in TWAS after potassium ferrate treatment with metal residual rates over 67.8% in TWAS. The distribution of metal speciation in WAS was affected by potassium ferrate treatment. The bioavailability and the mobility of heavy metals (except Mg) in TWAS were mitigated, compared to those in WAS. Meanwhile, the environmental risk of heavy metals (except Pb and Cu) was alleviated after potassium ferrate treatment.

  16. Application of Molecular Techniques to Elucidate the Influence of Cellulosic Waste on the Bacterial Community Structure at a Simulated Low-Level-Radioactive-Waste Site

    International Nuclear Information System (INIS)

    Field, Erin K.; D'Imperio, Seth; Miller, Amber R.; VanEngelen, Michael R.; Gerlach, Robin; Lee, Brady D.; Apel, William A.; Peyton, Brent M.

    2010-01-01

    Low-level radioactive waste sites, including those at various U.S. Department of Energy (DOE) sites, frequently contain cellulosic waste in the form of paper towels, cardboard boxes, or wood contaminated with heavy metals and radionuclides such as chromium and uranium. To understand how the soil microbial community is influenced by the presence of cellulosic waste products, multiple soil samples were obtained from a non-radioactive model low-level waste test pit at the Idaho National Laboratory. Samples were analyzed using 16S rDNA clone libraries and 16S rRNA gene microarray (PhyloChip) analyses. Both the clone library and PhyloChip results revealed changes in the bacterial community structure with depth. In all samples, the PhyloChip detected significantly more unique Operational Taxonomic Units (OTUs), and therefore more relative diversity, than the clone libraries. Calculated diversity indices suggest that diversity is lowest in the Fill (F) and Fill Waste (FW) layers and greater in the Wood Waste (WW) and Waste Clay (WC) layers. Principal coordinates analysis and lineage specific analysis determined that Bacteroidetes and Actinobacteria phyla account for most of the significant differences observed between the layers. The decreased diversity in the FW layer and increased members of families containing known cellulose degrading microorganisms suggests the FW layer is an enrichment environment for cellulose degradation. Overall, these results suggest that the presence of the cellulosic material significantly influences the bacterial community structure in a stratified soil system.

  17. Enhanced selective metal adsorption on optimised agroforestry waste mixtures.

    Science.gov (United States)

    Rosales, Emilio; Ferreira, Laura; Sanromán, M Ángeles; Tavares, Teresa; Pazos, Marta

    2015-04-01

    The aim of this work is to ascertain the potentials of different agroforestry wastes to be used as biosorbents in the removal of a mixture of heavy metals. Fern (FE), rice husk (RI) and oak leaves (OA) presented the best removal percentages for Cu(II) and Ni(II), Mn(II) and Zn(II) and Cr(VI), respectively. The performance of a mixture of these three biosorbents was evaluated, and an improvement of 10% in the overall removal was obtained (19.25mg/g). The optimum mixture proportions were determined using simplex-centroid mixture design method (FE:OA:RI=50:13.7:36.3). The adsorption kinetics and isotherms of the optimised mixture were fit by the pseudo-first order kinetic model and Langmuir isotherm. The adsorption mechanism was studied, and the effects of the carboxylic, hydroxyl and phenolic groups on metal-biomass binding were demonstrated. Finally, the recoveries of the metals using biomass were investigated, and cationic metal recoveries of 100% were achieved when acidic solutions were used. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Variation and distribution of metals and metalloids in soil/ash mixtures from Agbogbloshie e-waste recycling site in Accra, Ghana.

    Science.gov (United States)

    Itai, Takaaki; Otsuka, Masanari; Asante, Kwadwo Ansong; Muto, Mamoru; Opoku-Ankomah, Yaw; Ansa-Asare, Osmund Duodu; Tanabe, Shinsuke

    2014-02-01

    Illegal import and improper recycling of electronic waste (e-waste) are an environmental issue in developing countries around the world. African countries are no exception to this problem and the Agbogbloshie market in Accra, Ghana is a well-known e-waste recycling site. We have studied the levels of metal(loid)s in the mixtures of residual ash, formed by the burning of e-waste, and the cover soil, obtained using a portable X-ray fluorescence spectrometer (P-XRF) coupled with determination of the 1M HCl-extractable fraction by an inductively coupled plasma mass spectrometer. The accuracy and precision of the P-XRF measurements were evaluated by measuring 18 standard reference materials; this indicated the acceptable but limited quality of this method as a screening tool. The HCl-extractable levels of Al, Co, Cu, Zn, Cd, In, Sb, Ba, and Pb in 10 soil/ash mixtures varied by more than one order of magnitude. The levels of these metal(loid)s were found to be correlated with the color (i.e., soil/ash ratio), suggesting that they are being released from disposed e-waste via open burning. The source of rare elements could be constrained using correlation to the predominant metals. Human hazard quotient values based on ingestion of soil/ash mixtures exceeded unity for Pb, As, Sb, and Cu in a high-exposure scenario. This study showed that along with common metals, rare metal(loid)s are also enriched in the e-waste burning site. We suggest that risk assessment considering exposure to multiple metal(loid)s should be addressed in studies of e-waste recycling sites. © 2013. Published by Elsevier B.V. All rights reserved.

  19. Geophysical surveys for buried waste detection at the Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Sandness, G.A.; Rising, J.L.; Kimbrough, J.R.

    1979-12-01

    This report describes a series of geophysical surveys performed at the Idaho National Engineering Laboratory (INEL). The main purpose of the surveys was to evaluate techniques, principally ground-penetrating radar, for detecting and mapping radioactive wastes buried in shallow trenches and pits. A second purpose was to determine the feasibility of using ground-penetrating radar to measure the depth of basalt bedrock. A prototype geophyscal survey system developed by the US Department of Energy's Pacific Northwest Laboratory was used for this study. Radar, magnetometer, and metal detector measurements were made at three sites in the Radioactive Waste Management Complex (RWMC) at INEL. Radar measurements were made at fourth site adjacent to the RWMC. The combination of three geophysical methods was shown to provide considerable information about the distribution of buried waste materials. The tests confirmed the potential effectiveness of the radar method, but they also pointed out the need for continued research and development in ground-penetrating radar technology. The radar system tested in this study appears to be capable of measuring the depth to basalt in the vicinity of the RWMC

  20. Effects of heat input on the pitting resistance of Inconel 625 welds by overlay welding

    Science.gov (United States)

    Kim, Jun Seok; Park, Young IL; Lee, Hae Woo

    2015-03-01

    The objective of this study was to establish the relationship between the dilution ratio of the weld zone and pitting resistance depending on the heat input to welding of the Inconel alloy. Each specimen was produced by electroslag welding using Inconel 625 as the filler metal. In the weld zone of each specimen, dendrite grains were observed near the fusion line and equiaxed grains were observed on the surface. It was also observed that a melted zone with a high Fe content was formed around the fusion line, which became wider as the welding heat input increased. In order to evaluate the pitting resistance, potentiodynamic polarization tests and CPT tests were conducted. The results of these tests confirmed that there is no difference between the pitting resistances of each specimen, as the structures of the surfaces were identical despite the effect of the differences in the welding heat input for each specimen and the minor dilution effect on the surface.