WorldWideScience

Sample records for waste solidification performance

  1. Nuclear waste solidification

    Science.gov (United States)

    Bjorklund, William J.

    1977-01-01

    High level liquid waste solidification is achieved on a continuous basis by atomizing the liquid waste and introducing the atomized liquid waste into a reaction chamber including a fluidized, heated inert bed to effect calcination of the atomized waste and removal of the calcined waste by overflow removal and by attrition and elutriation from the reaction chamber, and feeding additional inert bed particles to the fluidized bed to maintain the inert bed composition.

  2. Performance testing of grout-based waste forms for the solidification of anion exchange resins

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, I.L.; Bostick, W.D.

    1990-10-01

    The solidification of spent ion exchanges resins in a grout matrix as a means of disposing of spent organic resins produced in the nuclear fuel cycle has many advantages in terms of process simplicity and economy, but associated with the process is the potential for water/cement/resins to interact and degrade the integrity of the waste form solidified. Described in this paper is one possible solution to preserving the integrity of these solidified waste forms: the encapsulation of beaded anion exchange resins in grout formulations containing ground granulated blast furnace slag, Type I-II (mixed) portland cement, and additives (clays, amorphous silica, silica fume, and fly ash). The results of the study reported herein show the cured waste form tested has a low leach rate for nitrate ion from the resin (and a low leach rate is inferred for Tc-99) and acceptable durability as assessed by the water immersion and freezing/thawing test protocols. The results also suggest a tested surrogate waste form prepared in vinyl ester styrene binder performs satisfactorily against the wetting/drying criterion, and it should offer additional insight into future work on the solidification of spent organic resins. 26 refs., 4 figs., 5 tabs.

  3. Polyethylene solidification of low-level wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kalb, P.D.; Colombo, P.

    1985-02-01

    This topical report describes the results of an investigation on the solidification of low-level radioactive waste in polyethylene. Waste streams selected for this study included those which result from advanced volume reduction technologies (dry evaporator concentrate salts and incinerator ash) and those which remain problematic for solidification using contemporary agents (ion exchange resins). Four types of commercially available low-density polyethylenes were employed which encompass a range of processing and property characteristics. Process development studies were conducted to ascertain optimal process control parameters for successful solidification. Maximum waste loadings were determined for each waste and polyethylene type. Property evaluation testing was performed on laboratory-scale specimens to assess the potential behavior of actual waste forms in a disposal environment. Waste form property tests included water immersion, deformation under compressive load, thermal cycling and radionuclide leaching. Recommended waste loadings of 70 wt % sodium sulfate, 50 wt % boric acid, 40 wt % incinerator ash, and 30 wt % ion exchange resins, which are based on process control and waste form performance considerations are reported. 37 refs., 33 figs., 22 tabs.

  4. Phosphate bonded solidification of radioactive incinerator wastes

    Energy Technology Data Exchange (ETDEWEB)

    Walker, B. W.; Langton, C. A.; Singh, D.

    1999-12-03

    The incinerator at the Department of Energy Savannah River Site burns low level radioactive and hazardous waste. Ash and scrubber system waste streams are generated during the incineration process. Phosphate Ceramic technology is being tested to verify the ash and scrubber waste streams can be stabilized using this solidification method. Acceptance criteria for the solid waste forms include leachability, bleed water, compression testing, and permeability. Other testing on the waste forms include x-ray diffraction and scanning electron microscopy.

  5. Solidification of radioactive waste resins using cement mixed with organic material

    Energy Technology Data Exchange (ETDEWEB)

    Laili, Zalina, E-mail: liena@nm.gov.my [Nuclear Science Programme, School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), Bangi, 43600, Selangor Malaysia (Malaysia); Waste and Environmental Technology Division, Malaysian Nuclear Agency (Nuclear Malaysia), Bangi, 43000 Kajang, Selangor (Malaysia); Yasir, Muhamad Samudi [Nuclear Science Programme, School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia (UKM), Bangi, 43600, Selangor Malaysia (Malaysia); Wahab, Mohd Abdul [Waste and Environmental Technology Division, Malaysian Nuclear Agency (Nuclear Malaysia), Bangi, 43000 Kajang, Selangor (Malaysia)

    2015-04-29

    Solidification of radioactive waste resins using cement mixed with organic material i.e. biochar is described in this paper. Different percentage of biochar (0%, 5%, 8%, 11%, 14% and 18%) was investigated in this study. The characteristics such as compressive strength and leaching behavior were examined in order to evaluate the performance of solidified radioactive waste resins. The results showed that the amount of biochar affect the compressive strength of the solidified resins. Based on the data obtained for the leaching experiments performed, only one formulation showed the leached of Cs-134 from the solidified radioactive waste resins.

  6. Method for solidification of radioactive and other hazardous waste

    Science.gov (United States)

    Anshits, Alexander G.; Vereshchagina, Tatiana A.; Voskresenskaya, Elena N.; Kostin, Eduard M.; Pavlov, Vyacheslav F.; Revenko, Yurii A.; Tretyakov, Alexander A.; Sharonova, Olga M.; Aloy, Albert S.; Sapozhnikova, Natalia V.; Knecht, Dieter A.; Tranter, Troy J.; Macheret, Yevgeny

    2002-01-01

    Solidification of liquid radioactive waste, and other hazardous wastes, is accomplished by the method of the invention by incorporating the waste into a porous glass crystalline molded block. The porous block is first loaded with the liquid waste and then dehydrated and exposed to thermal treatment at 50-1,000.degree. C. The porous glass crystalline molded block consists of glass crystalline hollow microspheres separated from fly ash (cenospheres), resulting from incineration of fossil plant coals. In a preferred embodiment, the porous glass crystalline blocks are formed from perforated cenospheres of grain size -400+50, wherein the selected cenospheres are consolidated into the porous molded block with a binder, such as liquid silicate glass. The porous blocks are then subjected to repeated cycles of saturating with liquid waste, and drying, and after the last cycle the blocks are subjected to calcination to transform the dried salts to more stable oxides. Radioactive liquid waste can be further stabilized in the porous blocks by coating the internal surface of the block with metal oxides prior to adding the liquid waste, and by coating the outside of the block with a low-melting glass or a ceramic after the waste is loaded into the block.

  7. Solidification/Stabilization of Elemental Mercury Waste by Amalgamation

    Energy Technology Data Exchange (ETDEWEB)

    Yim, S. P.; Ahn, B. G.; Lee, H. J.; Shon, J. S.; Chung, H.; Kim, K. J.; Lee, C. K.

    2003-02-24

    Experiments on solidification of elemental mercury waste were conducted by amalgamation with several metal powders such as copper, zinc, tin, brass and bronze. Unlike the previous studies which showed a dispersible nature after solidification, the waste forms were found to possess quite large compressive strengths in both copper and bronze amalgam forms. The durability was also confirmed by showing very minor changes of strength after 90 days of water immersion. Leachability from the amalgam forms is also shown to be low: measured mercury concentration in the leachate by the Toxicity Characteristic Leaching Procedure (TCLP) was well below the Environmental Protection Agency (EPA) limit. Long term leaching behavior by Accelerated Leach Test (ALT) has shown that the leaching process was dominated by diffusion and the effective diffusion coefficient was quite low (around 10-19 cm2/sec). The mercury vapor concentration from the amalgam forms were reduced to a 20% level of that for elemental mercury and to one-hundredth after 3 months.

  8. Study on solidification for municipal solid waste incineration fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Lu, C.; Liu, Q.; Yang, J.; Xi, W. [Chongqing Univ., Chongqing (China); Huang, B. [Southwest Petroleum Univ., Chengdu (China)

    2008-07-01

    The appropriate management of municipal solid waste (MSW) is a major environmental issues, despite the significant efforts to prevent, reduce, reuse and recycle waste. Two primary options can be used for managing MSW incineration fly ash. These are landfill disposal or incineration. Incineration is effective in toxic substance destruction, waste volume reduction and energy recovery, as compared with landfill. MSW fly ash generally contains higher content of easily leachable heavy metals such as lead, cadmium, and zinc. In China, source separation of municipal solid wastes is not well practiced and has resulted in high concentrations of heavy metals being detected in the MSW fly ash. This paper presented a preliminary study to examine the properties of MSW fly ash and the fixing abilities of ordinary Portland cement and hydrated time on heavy metals. The paper discussed the effects of experimental parameters on the properties of solidified fly ash and the optimal technology conditions. The fly ash used in the study was collected from solid waste incineration plants in Shenzhen, Shanghai, and Chongqing, China. It was concluded that the effect on solidification got better and the leaching quantities of heavy metals such as zinc, lead, cadmium, or chromium decreased with the addition of cement used as adhesive. The optimal proportion of cement was 8 per cent. 14 refs., 5 tabs., 2 figs.

  9. Laboratory stabilization/solidification of surrogate and actual mixed-waste sludge in glass and grout

    Energy Technology Data Exchange (ETDEWEB)

    Spence, R.D.; Gilliam, T.M.; Mattus, C.H.; Mattus, A.J.

    1998-03-03

    Grouting and vitrification are currently the most likely stabilization/solidification technologies for mixed wastes. Grouting has been used to stabilize and solidify hazardous and low-level waste for decades. Vitrification has long been developed as a high-level-waste alternative and has been under development recently as an alternative treatment technology for low-level mixed waste. Laboratory testing has been performed to develop grout and vitrification formulas for mixed-waste sludges currently stored in underground tanks at Oak Ridge National Laboratory (ORNL) and to compare these waste forms. Envelopes, or operating windows, for both grout and soda-lime-silica glass formulations for a surrogate sludge were developed. One formulation within each envelope was selected for testing the sensitivity of performance to variations ({+-}10 wt%) in the waste form composition and variations in the surrogate sludge composition over the range previously characterized in the sludges. In addition, one sludge sample of an actual mixed-waste tank was obtained, a surrogate was developed for this sludge sample, and grout and glass samples were prepared and tested in the laboratory using both surrogate and the actual sludge. The sensitivity testing of a surrogate tank sludge in selected glass and grout formulations is discussed in this paper, along with the hot-cell testing of an actual tank sludge sample.

  10. Utilization of coal fly ash in solidification of liquid radioactive waste from research reactor.

    Science.gov (United States)

    Osmanlioglu, Ahmet Erdal

    2014-05-01

    In this study, the potential utilization of fly ash was investigated as an additive in solidification process of radioactive waste sludge from research reactor. Coal formations include various percentages of natural radioactive elements; therefore, coal fly ash includes various levels of radioactivity. For this reason, fly ashes have to be evaluated for potential environmental implications in case of further usage in any construction material. But for use in solidification of radioactive sludge, the radiological effects of fly ash are in the range of radioactive waste management limits. The results show that fly ash has a strong fixing capacity for radioactive isotopes. Specimens with addition of 5-15% fly ash to concrete was observed to be sufficient to achieve the target compressive strength of 20 MPa required for near-surface disposal. An optimum mixture comprising 15% fly ash, 35% cement, and 50% radioactive waste sludge could provide the solidification required for long-term storage and disposal. The codisposal of radioactive fly ash with radioactive sludge by solidification decreases the usage of cement in solidification process. By this method, radioactive fly ash can become a valuable additive instead of industrial waste. This study supports the utilization of fly ash in industry and the solidification of radioactive waste in the nuclear industry.

  11. Solidification of Acidic, High Nitrate Nuclear Wastes by Grouting or Absorption on Silica Gel

    Energy Technology Data Exchange (ETDEWEB)

    A. K. Herbst; S. V. Raman; R. J. Kirkham

    2004-01-01

    The use of grout and silica gel were explored for the solidification of four types of acidic, high nitrate radioactive wastes. Two methods of grouting were tested: direct grouting and pre-neutralization. Two methods of absorption on silica gel were also tested: direct absorption and rotary spray drying. The waste simulant acidity varied between 1 N and 12 N. The waste simulant was neutralized by pre-blending calcium hydroxide with Portland cement and blast furnace slag powders prior to mixing with the simulant for grout solidification. Liquid sodium hydroxide was used to partially neutralize the simulant to a pH above 2 and then it was absorbed for silica gel solidification. Formulations for each of these methods are presented along with waste form characteristics and properties. Compositional variation maps for grout formulations are presented which help determine the optimum "recipe" for a particular waste stream. These maps provide a method to determine the proportions of waste, calcium hydroxide, Portland cement, and blast furnace slag that provide a waste form that meets the disposal acceptance criteria. The maps guide researchers in selecting areas to study and provide an operational envelop that produces acceptable waste forms. The grouts both solidify and stabilize the wastes, while absorption on silica gel produces a solid waste that will not pass standard leaching procedures (TCLP) if required. Silica gel wastes can be made to pass most leach tests if heated to 600ºC.

  12. Use of flue gas desulphurisation (FGD) waste and rejected fly ash in waste stabilization/solidification systems.

    Science.gov (United States)

    Qiao, X C; Poon, C S; Cheeseman, C

    2006-01-01

    Stabilization/solidification (S/S) processes have been used as the final treatment step for hazardous wastes prior to land disposal. Fly ash is a by-product of coal-fired power generation; a significant proportion of this material is low-grade, reject material (rFA) that is unsuitable as a cement replacement due to its high carbon content and large particle size (>45 microm). Flue gas desulphurization (FGD) sludge is a by-product from the air pollution control systems used in coal-fired power plants. The objective of this work was to investigate the performance of S/S waste binder systems containing these two waste materials (rFA and FGD). Strength tests show that cement-based waste forms with rFA and FGD replacement were suitable for disposal in landfills. The addition of an appropriate quantity of Ca(OH)2 and FGD reduces the deleterious effect of heavy metals on strength development. Results of TCLP testing and the progressive TCLP test show that cement-rFA-Ca(OH)2 systems with a range of FGD additions can form an effective S/S binder. The Leachability Index indicates that cement-based waste forms with rFA replacement were effective in reducing the mobility of heavy metals.

  13. Using cement, lignite fly ash and baghouse filter waste for solidification of chromium electroplating treatment sludge

    OpenAIRE

    Wantawin, C.; Chobthiangtham, P.

    2004-01-01

    The objective of the study is to use baghouse filter waste as a binder mixed with cement and lignite fly ash to solidify sludge from chromium electroplating wastewater treatment. To save cost of solidification, reducing cement in binder and increasing sludge in the cube were focused on. Minimum percent cement in binder of 20 for solidification of chromium sludge was found when controlling lignite fly ash to baghouse filter waste at the ratio of 30:70, sludge to binder ratio of 0.5, water to m...

  14. A literature review of mixed waste components: Sensitivities and effects upon solidification/stabilization in cement-based matrices

    Energy Technology Data Exchange (ETDEWEB)

    Mattus, C.H.; Gilliam, T.M.

    1994-03-01

    The US DOE Oak Ridge Field Office has signed a Federal Facility Compliance Agreement (FFCA) regarding Oak Ridge Reservation (ORR) mixed wastes subject to the land disposal restriction (LDR) provisions of the Resource conservation and Recovery Act. The LDR FFCA establishes an aggressive schedule for conducting treatability studies and developing treatment methods for those ORR mixed (radioactive and hazardous) wastes listed in Appendix B to the Agreement. A development, demonstration, testing, and evaluation program has been initiated to provide those efforts necessary to identify treatment methods for all of the wastes that meet Appendix B criteria. The program has assembled project teams to address treatment development needs in a variety of areas, including that of final waste forms (i.e., stabilization/solidification processes). A literature research has been performed, with the objective of determining waste characterization needs to support cement-based waste-form development. The goal was to determine which waste species are problematic in terms of consistent production of an acceptable cement-based waste form and at what concentrations these species become intolerable. The report discusses the following: hydration mechanisms of Portland cement; mechanisms of retardation and acceleration of cement set-factors affecting the durability of waste forms; regulatory limits as they apply to mixed wastes; review of inorganic species that interfere with the development of cement-based waste forms; review of radioactive species that can be immobilized in cement-based waste forms; and review of organic species that may interfere with various waste-form properties.

  15. Survey of agents and techniques applicable to the solidification of low-level radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Fuhrmann, M.; Neilson, R.M. Jr.; Colombo, P.

    1981-12-01

    A review of the various solidification agents and techniques that are currently available or potentially applicable for the solidification of low-level radioactive wastes is presented. An overview of the types and quantities of low-level wastes produced is presented. Descriptions of waste form matrix materials, the wastes types for which they have been or may be applied and available information concerning relevant waste form properties and characteristics follow. Also included are descriptions of the processing techniques themselves with an emphasis on those operating parameters which impact upon waste form properties. The solidification agents considered in this survey include: hydraulic cements, thermoplastic materials, thermosetting polymers, glasses, synthetic minerals and composite materials. This survey is part of a program supported by the United States Department of Energy's Low-Level Waste Management Program (LLWMP). This work provides input into LLWMP efforts to develop and compile information relevant to the treatment and processing of low-level wastes and their disposal by shallow land burial.

  16. Stabilization and Solidification of Nitric Acid Effluent Waste at Y-12

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Dileep [Argonne National Lab. (ANL), Argonne, IL (United States); Lorenzo-Martin, Cinta [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-12-16

    Consolidated Nuclear Security, LLC (CNS) at the Y-12 plant is investigating approaches for the treatment (stabilization and solidification) of a nitric acid waste effluent that contains uranium. Because the pH of the waste stream is 1-2, it is a difficult waste stream to treat and stabilize by a standard cement-based process. Alternative waste forms are being considered. In this regard, Ceramicrete technology, developed at Argonne National Laboratory, is being explored as an option to solidify and stabilize the nitric acid effluent wastes.

  17. Solidification Technologies for Radioactive and Chemical Liquid Waste Treatment - Final CRADA Report

    Energy Technology Data Exchange (ETDEWEB)

    Castiglioni, Andrew J. [Argonne National Lab. (ANL), Argonne, IL (United States); Gelis, Artem V. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-01-01

    This project, organized under DOE/NNSA's Global Initiatives for Proliferation Prevention program, joined Russian and DOE scientists in developing more effective solidification and storage technologies for liquid radioactive waste. Several patent applications were filed by the Russian scientists (Russia only) and in 2012, the technology developed was approved by Russia's Federal State Unitary Enterprise RADON for application throughout Russia in cleaning up and disposing of radioactive waste.

  18. WASTE SOLIDIFICATION BUILDING BENCH SCALE HIGH ACTIVITY WASTE SIMULANT VARIABILITY STUDY FY2008

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, E; Timothy Jones, T; Tommy Edwards, T; Alex Cozzi, A

    2009-03-20

    The primary objective of this task was to perform a variability study of the high activity waste (HAW) acidic feed to determine the impact of feed variability on the quality of the final grout and on the mixability of the salt solution into the dry powders. The HAW acidic feeds were processed through the neutralization/pH process, targeting a final pH of 12. These fluids were then blended with the dry materials to make the final waste forms. A secondary objective was to determine if elemental substitution for cost prohibitive or toxic elements in the simulant affects the mixing response, thus providing a more economical simulant for use in full scale tests. Though not an objective, the HAW simulant used in the full scale tests was also tested and compared to the results from this task. A statistically designed test matrix was developed based on the maximum molarity inputs used to make the acidic solutions. The maximum molarity inputs were: 7.39 HNO{sub 3}, 0.11618 gallium, 0.5423 silver, and 1.1032 'other' metals based on their NO{sub 3}{sup -} contribution. Substitution of the elements aluminum for gallium and copper for silver was also considered in this test matrix, resulting in a total of 40 tests. During the NaOH addition, the neutralization/pH adjustment process was controlled to a maximum temperature of 60 C. The neutralized/pH adjusted simulants were blended with Portland cement and zircon flour at a water to cement mass ratio of 0.30. The mass ratio of zircon flour to Portland cement was 1/12. The grout was made using a Hobart N-50 mixer running at low speed for two minutes to incorporate and properly wet the dry solids with liquid and at medium speed for five minutes for mixing. The resulting fresh grout was measured for three consecutive yield stress measurements. The cured grout was measured for set, bleed, and density. Given the conditions of preparing the grout in this task, all of the grouts were visually well mixed prior to preparing the

  19. Solidification/stabilisation of liquid oil waste in metakaolin-based geopolymer

    Energy Technology Data Exchange (ETDEWEB)

    Cantarel, V.; Nouaille, F.; Rooses, A.; Lambertin, D., E-mail: david.lambertin@cea.fr; Poulesquen, A.; Frizon, F.

    2015-09-15

    Highlights: • Formulation with 20 vol.% of oil in a geopolymer have been successful tested. • Oil waste is encapsulated as oil droplets in metakaolin-based geopolymer. • Oil/geopolymer composite present good mechanical performance. • Carbon lixiviation of oil/geopolymer composite is very low. - Abstract: The solidification/stabilisation of liquid oil waste in metakaolin based geopolymer was studied in the present work. The process consists of obtaining a stabilised emulsion of oil in a water-glass solution and then adding metakaolin to engage the setting of a geopolymer block with an oil emulsion stabilised in the material. Geopolymer/oil composites have been made with various oil fraction (7, 14 and 20 vol.%). The rigidity and the good mechanical properties have been demonstrated with compressive strength tests. Leaching tests evidenced the release of oil from the composite material is very limited whereas the constitutive components of the geopolymer (Na, Si and OH{sup −}) are involved into diffusion process.

  20. Immobilization of antimony waste slag by applying geopolymerization and stabilization/solidification technologies.

    Science.gov (United States)

    Salihoglu, Güray

    2014-11-01

    During the processing of antimony ore by pyrometallurgical methods, a considerable amount of slag is formed. This antimony waste slag is listed by the European Union as absolutely hazardous waste with a European Waste Catalogue code of 10 08 08. Since the levels of antimony and arsenic in the leachate of the antimony waste slag are generally higher than the landfilling limits, it is necessary to treat the slag before landfilling. In this study, stabilization/solidification and geopolymerization technologies were both applied in order to limit the leaching potential of antimony and arsenic. Different combinations ofpastes by using Portland cement, fly ash, clay, gypsum, and blast furnace slag were prepared as stabilization/solidification or geopoljymer matrixes. Sodium silicate-sodium hydroxide solution and sodium hydroxide solution at 8 M were used as activators for geopolymer samples. Efficiencies of the combinations were evaluated in terms of leaching and unconfined compressive strength. None of the geopolymer samples prepared with the activators yielded arsenic and antimony leaching below the regulatory limit at the same time, although they yielded high unconfined compressive strength levels. On the other hand, the stabilization/solidification samples prepared by using water showed low leaching results meeting the landfilling criteria. Use of gypsum as an additive was found to be successful in immobilizing the arsenic and antimony.

  1. Using cement, lignite fly ash and baghouse filter waste for solidification of chromium electroplating treatment sludge

    Directory of Open Access Journals (Sweden)

    Wantawin, C.

    2004-02-01

    Full Text Available The objective of the study is to use baghouse filter waste as a binder mixed with cement and lignite fly ash to solidify sludge from chromium electroplating wastewater treatment. To save cost of solidification, reducing cement in binder and increasing sludge in the cube were focused on. Minimum percent cement in binder of 20 for solidification of chromium sludge was found when controlling lignite fly ash to baghouse filter waste at the ratio of 30:70, sludge to binder ratio of 0.5, water to mixer ratio of 0.3 and curing time of 7 days. Increase of sludge to binder ratio from 0.5 to 0.75 and 1 resulted in increase in the minimum percent cement in binder up to 30 percent in both ratios. With the minimum percent cement in binder, the calculated cement to sludge ratios for samples with sludge to binder ratios of 0.5, 0.75 and 1 were 0.4, 0.4 and 0.3 respectively. Leaching chromium and compressive strength of the samples with these ratios could achieve the solidified waste standard by the Ministry of Industry. For solidification of chromium sludge at sludge to binder ratio of 1, the lowest cost binder ratio of cement to lignite fly ash and baghouse filter waste in this study was 30:21:49. The cost of binder in this ratio was 718 baht per ton dry sludge.

  2. Effective solidification/stabilisation of mercury-contaminated wastes using zeolites and chemically bonded phosphate ceramics.

    Science.gov (United States)

    Zhang, Shaoqing; Zhang, Xinyan; Xiong, Ya; Wang, Guoping; Zheng, Na

    2015-02-01

    In this study, two kinds of zeolites materials (natural zeolite and thiol-functionalised zeolite) were added to the chemically bonded phosphate ceramic processes to treat mercury-contaminated wastes. Strong promotion effects of zeolites (natural zeolite and thiol-functionalised zeolite) on the stability of mercury in the wastes were obtained and these technologies showed promising advantages toward the traditional Portland cement process, i.e. using Portland cement as a solidification agent and natural or thiol-functionalised zeolite as a stabilisation agent. Not only is a high stabilisation efficiency (lowered the Toxicity Characteristic Leaching Procedure Hg by above 10%) obtained, but also a lower dosage of solidification (for thiol-functionalised zeolite as stabilisation agent, 0.5 g g(-1) and 0.7 g g(-1) for chemically bonded phosphate ceramic and Portland cement, respectively) and stabilisation agents (for natural zeolite as stabilisation agent, 0.35 g g(-1) and 0.4 g g(-1) for chemically bonded phosphate ceramic and Portland cement, respectively) were used compared with the Portland cement process. Treated by thiol-functionalised zeolite and chemically bonded phosphate ceramic under optimum parameters, the waste containing 1500 mg Hg kg(-1) passed the Toxicity Characteristic Leaching Procedure test. Moreover, stabilisation/solidification technology using natural zeolite and chemically bonded phosphate ceramic also passed the Toxicity Characteristic Leaching Procedure test (the mercury waste containing 625 mg Hg kg(-1)). Moreover, the presence of chloride and phosphate did not have a negative effect on the chemically bonded phosphate ceramic/thiol-functionalised zeolite treatment process; thus, showing potential for future application in treatment of 'difficult-to-manage' mercury-contaminated wastes or landfill disposal with high phosphate and chloride content. © The Author(s) 2015.

  3. Solidification of coal mining wastes using pozzolanic fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Laczny, J.M.; Dabrowska, L. [Inst. for Ecology of Industrial Areas, Katowice (Poland)

    2001-07-01

    A detailed analysis of chemical composition of porous waters in coal mining wastes and fly ashes has shown that there is a possibility of such alternate disposal which would facilitate forming a protective barrier, which due to reactions undergoing between chemical compounds of both phases would result in forming the so called 'reactive barrier'. This new solution is under patent procedure. 6 refs.

  4. Preliminary evaluation of alternative waste form solidification processes. Volume I. Identification of the processes.

    Energy Technology Data Exchange (ETDEWEB)

    Treat, R.L.; Nesbitt, J.F.; Blair, H.T.; Carter, J.G.; Gorton, P.S.; Partain, W.L.; Timmerman, C.L.

    1980-04-01

    This document contains preconceptual design data on 11 processes for the solidification and isolation of nuclear high-level liquid wastes (HLLW). The processes are: in-can glass melting (ICGM) process, joule-heated glass melting (JHGM) process, glass-ceramic (GC) process, marbles-in-lead (MIL) matrix process, supercalcine pellets-in-metal (SCPIM) matrix process, pyrolytic-carbon coated pellets-in-metal (PCCPIM) matrix process, supercalcine hot-isostatic-pressing (SCHIP) process, SYNROC hot-isostatic-pressing (SYNROC HIP) process, titanate process, concrete process, and cermet process. For the purposes of this study, it was assumed that each of the solidification processes is capable of handling similar amounts of HLLW generated in a production-sized fuel reprocessing plant. It was also assumed that each of the processes would be enclosed in a shielded canyon or cells within a waste facility located at the fuel reprocessing plant. Finally, it was assumed that all of the processes would be subject to the same set of regulations, codes and standards. Each of the solidification processes converts waste into forms that may be acceptable for geological disposal. Each process begins with the receipt of HLLW from the fuel reprocessing plant. In this study, it was assumed that the original composition of the HLLW would be the same for each process. The process ends when the different waste forms are enclosed in canisters or containers that are acceptable for interim storage. Overviews of each of the 11 processes and the bases used for their identification are presented in the first part of this report. Each process, including its equipment and its requirements, is covered in more detail in Appendices A through K. Pertinent information on the current state of the art and the research and development required for the implementation of each process are also noted in the appendices.

  5. High level liquid waste solidification using a ''Cold' crucible induction melter

    Energy Technology Data Exchange (ETDEWEB)

    Demine, A.V.; Krylova, N.V.; Polyektov, P.P.; Shestoperov, I.N.; Smelova, T.V. [SSC RF VNIINM, Moscow (Russian Federation); Gorn, V.F.; Medvedev, G.M. [IA ' ' MAYAK' ' , Ozersk (Russian Federation)

    2000-07-01

    At the present time the primary problem in a closed nuclear fuel cycle is the management of high level liquid waste (HLLW) generated by the recovery of uranium and plutonium from the spent nuclear fuel. Long-term storage of the HLLW, even in special storage facilities, poses a real threat of ecological accidents. This problem can be solved by incorporating the radioactive waste into solid fixed forms that minimize the potential for biosphere pollution by long-lived radionuclides and ensure ecologically acceptable safe storage, transportation, and disposal. In the present report, the advantages of a two-stage HLLW solidification process using a 'cold' crucible induction melter (CCIM) are considered in comparison with a one-stage vitrification process in a ceramic melter. This paper describes the features of a process and equipment for two-stage HLLW solidification technology using a 'cold' crucible induction melter (CCIM) and its advantages compared to a one stage ceramic melter. A two-stage pilot facility and the technical characteristics of the equipment are described using a once-through evaporated and induction cold-crucible melter currently operational at the IA 'Mayak' facility in Ozersk, Russia. The results of pilot-plant tests with simulated HLLW to produce a phosphate glass are described. Features of the new mineral-like waste form matrices synthesized by the CCIM method are also described. Subject to further development, the CCIM technology is planned to be used to solidify all accumulated HLLW at Mayak - first to produce borosilicate glass waste forms then mineral-like waste forms. (authors)

  6. Stabilization/solidification of a municipal solid waste incineration residue using fly ash-based geopolymers.

    Science.gov (United States)

    Luna Galiano, Y; Fernández Pereira, C; Vale, J

    2011-01-15

    The stabilization/solidification (S/S) of a municipal solid waste incineration (MSWI) fly ash containing hazardous metals such as Pb, Cd, Cr, Zn or Ba by means of geopolymerization technology is described in this paper. Different reagents such as sodium hydroxide, potassium hydroxide, sodium silicate, potassium silicate, kaolin, metakaolin and ground blast furnace slag have been used. Mixtures of MSWI waste with these kinds of geopolymeric materials and class F coal fly ash used as silica and alumina source have been processed to study the potential of geopolymers as waste immobilizing agents. To this end, the effects of curing conditions and composition have been tested. S/S solids are submitted to compressive strength and leaching tests to assess the results obtained and to evaluate the efficiency of the treatment. Compressive strength values in the range 1-9 MPa were easily obtained at 7 and 28 days. Concentrations of the metals leached from S/S products were strongly pH dependent, showing that the leachate pH was the most important variable for the immobilization of metals. Comparison of fly ash-based geopolymer systems with classical Portland cement stabilization methods has also been accomplished. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Waste stabilization/solidification of an electric arc furnace dust using fly ash-based geopolymers

    Energy Technology Data Exchange (ETDEWEB)

    C. Fernandez Pereira; Y. Luna; X. Querol; D. Antenucci; J. Vale [University of Seville, Seville (Spain). School of Industrial Engineering

    2009-07-15

    The stabilization/solidification (S/S) of a carbon steel electric arc furnace (EAF) dust containing hazardous metals such as Pb, Cd, Cr or Zn using geopolymerization technology is described in this paper. Different reagents such as sodium hydroxide, potassium hydroxide, sodium silicate, potassium silicate, kaolinite, metakaolinite and blast furnace slag have been used. Mixtures of EAF waste with these geopolymeric materials and class F fly ash have been processed for studying the potential of geopolymers as waste immobilizing agents. Compressive strength tests and leaching tests for determining the efficiency of heavy metal immobilisation have been carried out. Comparison of fly ash-based geopolymer systems with classic Portland cement stabilization methods has also been accomplished. Compressive strength values far better than those achieved by hydraulic S/S methods were easily obtained by geopolymer solids at 28 days. Regarding leachability, the geopolymer S/S solids also manifested in general a better behaviour, showing very promising results. 40 refs., 1 fig., 9 tabs.

  8. Design of a novel system allowing the selection of an adequate binder for solidification/stabilization of wastes

    Energy Technology Data Exchange (ETDEWEB)

    Pera, J.; Thevenin, G.; Chabannet, M. [INSA de Lyon, Villeurbanne (France)

    1997-10-01

    Literature review shows that there is a lack of complete and consistent data on waste-binder interactions. Few links exist between research on the Solidification/Stabilization (S/S) mechanisms and the formulation of binders for immobilization. Therefore, a twofold program was developed allowing both to be done in parallel. This protocol had two targets: understanding the mechanisms involved in the S/S of heavy metals for each type of binder and rating the binder capacity for fixing heavy metals. The experimental procedure relies on two substrates: (1) the study of suspensions by means of conductimetry, XRD, FTIR, DTA, SEM-EDXA, ICP, ion chromatography, and colorimetry; and (2) the study of pure pastes for leaching tests and microstructural characterization (XRD, FTIR, DTA, SEM-EDXA). Results confirm whether the pollutant modifies the hydration or not, give access to the extent of binder stabilization without taking into account the solidification part, and elucidate the mechanisms involved.

  9. Sulfur polymer stabilization/solidification (SPSS) treatment of mixed waste mercury recovered from environmental restoration activities at BNL

    Energy Technology Data Exchange (ETDEWEB)

    Kalb, P.; Adams, J.; Milian, L.

    2001-01-29

    Over 1,140 yd{sup 3} of radioactively contaminated soil containing toxic mercury (Hg) and several liters of mixed-waste elemental mercury were generated during a Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) removal action at Brookhaven National Laboratory (BNL). The US Department of Energy's (DOE) Office of Science and Technology Mixed Waste Focus Area (DOE MWFA) is sponsoring a comparison of several technologies that may be used to treat these wastes and similar wastes at BNL and other sites across the DOE complex. This report describes work conducted at BNL on the application and pilot-scale demonstration of the newly developed Sulfur Polymer Stabilization/Solidification (SPSS) process for treatment of contaminated mixed-waste soils containing high concentrations ({approximately} 5,000 mg/L) of mercury and liquid elemental mercury. BNL's SPSS (patent pending) process chemically stabilizes the mercury to reduce vapor pressure and leachability and physically encapsulates the waste in a solid matrix to eliminate dispersion and provide long-term durability. Two 55-gallon drums of mixed-waste soil containing high concentrations of mercury and about 62 kg of radioactive contaminated elemental mercury were successfully treated. Waste loadings of 60 wt% soil were achieved without resulting in any increase in waste volume, while elemental mercury was solidified at a waste loading of 33 wt% mercury. Toxicity Characteristic Leaching Procedure (TCLP) analyses indicate the final waste form products pass current Environmental Protection Agency (EPA) allowable TCLP concentrations as well as the more stringent proposed Universal Treatment Standards. Mass balance measurements show that 99.7% of the mercury treated was successfully retained within the waste form, while only 0.3% was captured in the off gas system.

  10. Grout and glass performance in support of stabilization/solidification of ORNL tank sludges

    Energy Technology Data Exchange (ETDEWEB)

    Spence, R.D.; Mattus, C.H.; Mattus, A.J.

    1998-09-01

    Wastewater at Oak Ridge National Laboratory (ORNL) is collected, evaporated, and stored in the Melton Valley Storage Tanks (MVST) and Bethel Valley Evaporator Storage Tanks (BVEST) pending treatment for disposal. In addition, some sludges and supernatants also requiring treatment remain in two inactive tank systems: the gunite and associated tanks (GAAT) and the old hydrofracture (OHF) tank. The waste consists of two phases: sludge and supernatant. The sludges contain a high amount of radioactivity, and some are classified as TRU sludges. Some Resource Conservation and Recovery Act (RCRA) metal concentrations are high enough to be defined as RCRA hazardous; therefore, these sludges are presumed to be mixed TRU waste. Grouting and vitrification are currently two likely stabilization/solidification alternatives for mixed wastes. Grouting has been used to stabilize/solidify hazardous and low-level radioactive waste for decades. Vitrification has been developed as a high-level radioactive alternative for decades and has been under development recently as an alternative disposal technology for mixed waste. The objective of this project is to define an envelope, or operating window, for grout and glass formulations for ORNL tank sludges. Formulations will be defined for the average composition of each of the major tank farms (BVEST/MVST, GAAT, and OHF) and for an overall average composition of all tank farms. This objective is to be accomplished using surrogates of the tank sludges with hot testing of actual tank sludges to check the efficacy of the surrogates.

  11. Study of stabilization/solidification processes (of solid porous wastes) based on hydraulic or bituminous binders; Etude des procedes de stabilisation/solidification (des dechets solides poreux) a base de liants hydrauliques ou de liants bitumineux

    Energy Technology Data Exchange (ETDEWEB)

    Sing-Teniere, Ch.

    1998-02-01

    The first part of this thesis presents the regulatory framework and the technical context linked with the study of stabilized/solidified wastes and with the evaluation of stabilization/solidification processes. A presentation of the two type of ultimate wastes under study (a used catalyst and an activated charcoal) and an analysis of the processes is given. The second part is devoted to the experimental characterization of both types of porous wastes. The third part deals with the processing of such wastes using an hydraulic binder. The study stresses on both on the stabilization/solidification efficiency of the process and on the conditions of its implementation. The same work is made for a process that uses a bituminous binder. Some choice criteria for the selection of the better process are deduced from the examination of the overall data collected. The waste characterization methodology is applied six times: two times for the raw wastes, two times for the same wastes processed with an hydraulic binder, and two times for the same wastes processed with a bituminous binder. (J.S.)

  12. Stabilization/solidification of a porous waste by an hydraulic binder. Effects of grain size on the quality of the solidified product. Industrial test; Stabilisation/solidification d`un dechet poreux par un liant hydraulique influence de la granulometrie sur la qualite du produit solidifie, test industriel

    Energy Technology Data Exchange (ETDEWEB)

    Eyraud, P.; Teniere, C. [Groupement de Recherches de Lacq, 64 (France)

    1997-12-31

    The solidification of a porous and highly reactive waste (a catalyst that has been used for sulfuric acid) by the mean of a hydraulic binder, has been studied. Three different grain size distributions have been tested in order to determine if grinding is required before stabilization/solidification. The solidified waste is then evaluated through the SRETIE protocol. Site tests allowed for the optimization of an industrial scale implementation

  13. Small hazardous waste generators in developing countries: use of stabilization/solidification process as an economic tool for metal wastewater treatment and appropriate sludge disposal.

    Science.gov (United States)

    Silva, Marcos A R; Mater, Luciana; Souza-Sierra, Maria M; Corrêa, Albertina X R; Sperb, Rafael; Radetski, Claudemir M

    2007-08-25

    The aim of this study was to propose a profitable destination for an industrial sludge that can cover the wastewater treatment costs of small waste generators. Optimized stabilization/solidification technology was used to treat hazardous waste from an electroplating industry that is currently released untreated to the environment. The stabilized/solidified (S/S) waste product was used as a raw material to build concrete blocks, to be sold as pavement blocks or used in roadbeds and/or parking lots. The quality of the blocks containing a mixture of cement, lime, clay and waste was evaluated by means of leaching and solubility tests according to the current Brazilian waste regulations. Results showed very low metal leachability and solubility of the block constituents, indicating a low environmental impact. Concerning economic benefits from the S/S process and reuse of the resultant product, the cost of untreated heavy metal-containing sludge disposal to landfill is usually on the order of US$ 150-200 per tonne of waste, while 1tonne of concrete roadbed blocks (with 25% of S/S waste constitution) has a value of around US$ 100. The results of this work showed that the cement, clay and lime-based process of stabilization/solidification of hazardous waste sludge is sufficiently effective and economically viable to stimulate the treatment of wastewater from small industrial waste generators.

  14. Grout performance in support of in situ stabilization/solidification of the GAAT tank sludges

    Energy Technology Data Exchange (ETDEWEB)

    Spence, R. D. [Oak Ridge National Lab., TN (United States); Kauschinger, J. L. [Ground Environmental Services, Inc., Alpharetta, GA (United States)

    1997-05-01

    The Gunite{trademark} and associated tanks (GAATs) were constructed at ORNL between 1943 and 1951 and were used for many years to collect radioactive and chemical wastes. These tanks are currently inactive. Varying amounts of the sludge were removed and disposed of through the Hydrofracture Program. Thus, some tanks are virtually empty, while others still contain significant amounts of sludge and supernatant. In situ grouting of the sludges in the tanks using multi-point injection (MPI{trademark}), a patented, proprietary technique, is being investigated as a low-cost alternative to (1) moving the sludges to the Melton Valley Storage Tanks (MVSTs) for later solidification and disposal, (2) ex situ grouting of the sludges followed by either disposal back in the tanks or containerizing and disposal elsewhere, and (3) vitrification of the sludges. The paper discusses the chemical characteristics of the GAATs and the type of chemical surrogate that was used during the leachability tests. T his is followed by the experimental work, which, consisted of scope testing and sensitivity testing. The scope testing explored the rheology of the proposed jetting slurries and the settling properties of the proposed grouts using sand-water mixes for the wet sludge. After establishing a jetting slurry and grout with an acceptable rheology and settling properties, the proposed in situ grout formulation was subjected to sensitivity testing for variations in the formulation.

  15. Spray Calciner/In-Can Melter high-level waste solidification technical manual

    Energy Technology Data Exchange (ETDEWEB)

    Larson, D.E. (ed.)

    1980-09-01

    This technical manual summarizes process and equipment technology developed at Pacific Northwest Laboratory over the last 20 years for vitrification of high-level liquid waste by the Spray Calciner/In-Can Melter process. Pacific Northwest Laboratory experience includes process development and demonstration in laboratory-, pilot-, and full-scale equipment using nonradioactive synthetic wastes. Also, laboratory- and pilot-scale process demonstrations have been conducted using actual high-level radioactive wastes. In the course of process development, more than 26 tonnes of borosilicate glass have been produced in 75 canisters. Four of these canisters contained radioactive waste glass. The associated process and glass chemistry is discussed. Technology areas described include calciner feed treatment and techniques, calcination, vitrification, off-gas treatment, glass containment (the canister), and waste glass chemistry. Areas of optimization and site-specific development that would be needed to adapt this base technology for specific plant application are indicated. A conceptual Spray Calciner/In-Can Melter system design and analyses are provided in the manual to assist prospective users in evaluating the process for plant application, to provide equipment design information, and to supply information for safety analyses and environmental reports. The base (generic) technology for the Spray Calciner/In-Can Melter process has been developed to a point at which it is ready for plant application.

  16. Solidification/stabilization of ash from medical waste incineration into geopolymers.

    Science.gov (United States)

    Tzanakos, Konstantinos; Mimilidou, Aliki; Anastasiadou, Kalliopi; Stratakis, Antonis; Gidarakos, Evangelos

    2014-10-01

    In the present work, bottom and fly ash, generated from incinerated medical waste, was used as a raw material for the production of geopolymers. The stabilization (S/S) process studied in this paper has been evaluated by means of the leaching and mechanical properties of the S/S solids obtained. Hospital waste ash, sodium hydroxide, sodium silicate solution and metakaolin were mixed. Geopolymers were cured at 50°C for 24h. After a certain aging time of 7 and 28 days, the strength of the geopolymer specimens, the leachability of heavy metals and the mineralogical phase of the produced geopolymers were studied. The effects of the additions of fly ash and calcium compounds were also investigated. The results showed that hospital waste ash can be utilized as source material for the production of geopolymers. The addition of fly ash and calcium compounds considerably improves the strength of the geopolymer specimens (2-8 MPa). Finally, the solidified matrices indicated that geopolymerization process is able to reduce the amount of the heavy metals found in the leachate of the hospital waste ash. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Critical Review of Cement-Based Stabilisation/Solidification Techniques for the Disposal of Hazardous Wastes.

    Science.gov (United States)

    1986-12-01

    wollastonite. J. Chem. Tech. Biotechnol., 34A, 367-373 (1984). 34 R. Papachristou. In Flyash for defluoridation . Water and Waste Treatment, 28 (5), 40...porosity of the solidified product (eg. by using an extreme low water /cement ratio or the use of polymer impregnation techniques). It has also been...would finally appear in water as sodium, potassium and calcium sulphate. 6 It should be noted that the characteristics of PFA vary with ;ts source. Even

  18. Special Analysis for the Disposal of the Consolidated Edison Uranium Solidification Project Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Management

    2013-01-31

    The purpose of this Special Analysis (SA) is to determine if the Oak Ridge (OR) Consolidated Edison Uranium Solidification Project (CEUSP) uranium-233 (233U) waste stream (DRTK000000050, Revision 0) is acceptable for shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada National Security Site (NNSS). The CEUSP 233U waste stream requires a special analysis because the concentrations of thorium-229 (229Th), 230Th, 232U, 233U, and 234U exceeded their NNSS Waste Acceptance Criteria action levels. The acceptability of the waste stream is evaluated by determining if performance assessment (PA) modeling provides a reasonable expectation that SLB disposal is protective of human health and the environment. The CEUSP 233U waste stream is a long-lived waste with unique radiological hazards. The SA evaluates the long-term acceptability of the CEUSP 233U waste stream for near-surface disposal as a two tier process. The first tier, which is the usual SA process, uses the approved probabilistic PA model to determine if there is a reasonable expectation that disposal of the CEUSP 233U waste stream can meet the performance objectives of U.S. Department of Energy Manual DOE M 435.1-1, “Radioactive Waste Management,” for a period of 1,000 years (y) after closure. The second tier addresses the acceptability of the OR CEUSP 233U waste stream for near-surface disposal by evaluating long-term site stability and security, by performing extended (i.e., 10,000 and 60,000 y) modeling analyses, and by evaluating the effect of containers and the depth of burial on performance. Tier I results indicate that there is a reasonable expectation of compliance with all performance objectives if the OR CEUSP 233U waste stream is disposed in the Area 5 RWMS SLB disposal units. The maximum mean and 95th percentile PA results are all less than the performance objective for 1,000 y. Monte Carlo uncertainty analysis indicates that there is a high likelihood of

  19. Solidification of Simulated Liquid Effluents Originating From Sodium-Bearing Waste at the Idaho Nuclear Technology and Engineering Center, FY-03 Report

    Energy Technology Data Exchange (ETDEWEB)

    S. V. Raman; A. K. Herbst; B. A. Scholes; S. H. Hinckley; R. D. Colby

    2003-09-01

    In this report, the mechanism and methods of fixation of acidic waste effluents in grout form are explored. From the variations in the pH as a function of total solids addition to acidic waste effluent solutions, the stages of gellation, liquefaction, slurry formation and grout development are quantitatively revealed. Experimental results indicate the completion of these reaction steps to be significant for elimination of bleed liquid and for setting of the grout to a dimensionally stable and hardened solid within a reasonable period of about twenty eight days that is often observed in the cement and concrete industry. The reactions also suggest increases in the waste loading in the direction of decreasing acid molarity. Consequently, 1.0 molar SBW-180 waste is contained in higher quantity than the 2.8 molar SBW-189, given the same grout formulation for both effluents. The variations in the formulations involving components of slag, cement, waste and neutralizing agent are represented in the form of a ternary formulation map. The map in turn graphically reveals the relations among the various formulations and grout properties, and is useful in predicting the potential directions of waste loading in grouts with suitable properties such as slurry viscosity, Vicat hardness, and mechanical strength. A uniform formulation for the fixation of both SBW-180 and SBW-189 has emerged from the development of the formulation map. The boundaries for the processing regime on this map are 100 wt% cement to 50 wt% cement / 50 wt% slag, with waste loadings ranging from 55 wt% to 68 wt%. Within these compositional bounds all the three waste streams SBW-180, SBW-189 and Scrub solution are amenable to solidification. A large cost advantage is envisaged to stem from savings in labor, processing time, and processing methodology by adopting a uniform formulation concept for fixation of compositionally diverse waste streams. The experimental efforts contained in this report constitute the

  20. Prediction of solidification and phase transformation in weld metals for welding of high performance stainless steels; Kotaishoku kotainetsu stainless koyo yosetsu kinzoku no gyoko hentai no yosoku gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Koseki, T.; Inoue, H.; Morimoto, H.; Okita, S. [Nippon Steel Corp., Tokyo (Japan)

    1995-02-28

    Prediction technology is introduced on the solidification and transformation of weld metals used for high performance stainless steel. A model has been developed which uses Thermo Calc, a multiple balanced calculation program, as a means to analyze the solidification of multi-component alloys including the polyphase solidification such as eutectic and peritectic. Verification has been in progress concerning the adequacy of this model and the adaptability as a practical steel. The following are the prediction technologies for solidification and transformation which have been derived from experiments and applied to welding techniques: the effects of nitrogen on the solidification mode and residual {gamma}quantity of a welding metal that is required for controlling the welding/solidification of high nitrogen content {gamma}system stainless steel; the structural control of weld metal for high corrosion resistance high Mo stainless steel, in which high Ni and high Mo contents are indispensable for attaining the optimum structure; the structural control of weld metal for two-phase stainless steel containing Mo and N, in which it is essential to secure a high nitrogen content and a {delta}/{gamma}phase balance in a weld metal; and the precipitation prediction of intermetallic compound in a high alloy weld metal for a high alloy stainless steel, for which an explanation is there by Cieslak et al. based on the phase stability theory. 22 refs., 16 figs.

  1. Stable solidification of silica-based ammonium molybdophosphate by allophane: Application to treatment of radioactive cesium in secondary solid wastes generated from fukushima.

    Science.gov (United States)

    Wu, Yan; Lee, Chuan-Pin; Mimura, Hitoshi; Zhang, Xiaoxia; Wei, Yuezhou

    2018-01-05

    Silica-based ammonium molybdophosphate (AMP/SiO2) is an absorbent material that can effectively remove Cs from radioactive-contaminated wastewater (RCW) generated by Fukushima nuclide accident. Pressing/sintering method was used for final disposal of secondary waste (spent absorbent) to achieve the volume reduction of AMP-Cs/SiO2 (AMP/SiO2 saturation adsorption of Cs) and stable solidification of Cs by adding natural allophane. The structure of AMP-Cs completely collapsed at approximately 700°C, and most Mo and P species in AMP sublimed. The optimal sintering temperature was estimated as 900°C. The stable crystalline phase of Cs4Al4Si20O48 was recrystallized by the reaction of Cs2O, Al2O3, and SiO2, and the immobilization ratio of Cs was approximately 100%. The leachability of Cs from the sintered product in distilled water was approximately 0.41%. The high immobilization and low leachability of Cs were attributed to the excellent solidification properties of the sintered products of AMP-Cs/SiO2-allophane. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Grout and Glass Performance in Support of Stabilization/Solidification of the MVST Tank Sludges

    Energy Technology Data Exchange (ETDEWEB)

    Gilliam, T.M.; Spence, R.D.

    1998-11-01

    Wastewater at Oak Ridge National Laboratory (ORNL) is collected, evaporated, and stored in the Melton Valley Storage Tanks (MVST) pending treatment for disposal. The waste separates into two phases: sludge and supematant. Some of the supematant from these tanks has been decanted, solidified into a grout, and stored for disposal as a solid low-level waste. The sludges in the tank bottoms have been accumulating ,for several years. Some of the sludges contain a high amount of gamma activity (e.g., `37CS concentration range of 0.01 3-11 MBq/g) and contain enough transuranic (TRU) radioisotopes to be classified as TRU wastes. Some Resource Conservation and Recovery Act (RCRA) metal concentrations are high enough in the available total constituent analysis for the MVST sludge to be classified as RCRA hazardous; therefore, these sludges are presumed to be mixed TRU waste.

  3. Performance Evaluation of Waste Plastic Oil Converter

    Directory of Open Access Journals (Sweden)

    Elmo C. Rapsing, Jr.

    2017-05-01

    Full Text Available This research aimed to evaluate the performance of the waste plastic oil converter. The equipment is a prototype model powered by electricity and utilizes a non-catalytic pyrolysis process of converting waste plastic to oil. The primary objective of the study is to identify the type of waste plastic that the equipment can process and determine its performance in terms of conversion efficiency (wt %, waste reduction efficiency (wt % and oil recovery (ml oil/kg waste plastic. The equipment was initially tested for Type 1-Polyethylene Terephthalate, Type 2-High Density Polyethylene, Type 4-Low Density Polyethylene, Type 5-Polypropylene and Type 6 -Polystyrene. It was observed that the equipment is only capable of converting Type 5 and 6 waste plastic into oil. For the performance evaluation of the equipment, 1000g Type 5 and 1000g Type 6 waste plastic were used as feedstock. The experiments were performed separately for each of them. Five trials using 200g per trial for each type of plastic was conducted to test the equipment. The temperature at the bottom of the reactor was set to 4000C and the operating time was 2 hour per trial with 15 minutes cracking time, 1 minute vapor residence time and 1 minute vapor evacuation time. Results show that the conversion efficiency of the equipment for Type 5 was 60.90% and for Type 6 was 83.6%. Waste reduction efficiency was 94.8% for Type 5 and 95.6% for Type 6. The oil recovery of the equipment was 766 ml/kg for Type 5 and 919 ml/kg for Type 6. Thus, the waste plastic oil converter is a potential solution in reducing the amount of plastic waste due to its capability of producing oil out ofwaste Type 5 and Type 6 plastics.

  4. Melting, solidification, remelting, and separation of glass and metal

    Energy Technology Data Exchange (ETDEWEB)

    Ebadian, M.A.; Xin, R.C.; Liu, Y.Z.

    1998-01-01

    Several high-temperature vitrification technologies have been developed for the treatment of a wide range of mixed waste types in both the low-level waste and transuranic (TRU) mixed waste categories currently in storage at DOE sites throughout the nation. The products of these processes are an oxide slag phase and a reduced metal phase. The metal phase has the potential to be recycled within the DOE Complex. Enhanced slag/metal separation methods are needed to support these processes. This research project involves an experimental investigation of the melting, solidification, remelting, and separation of glass and metal and the development of an efficient separation technology. The ultimate goal of this project is to find an efficient way to separate the slag phase from the metal phase in the molten state. This two-year project commenced in October 1995 (FY96). In the first fiscal year, the following tasks were accomplished: (1) A literature review and an assessment of the baseline glass and metal separation technologies were performed. The results indicated that the baseline technology yields a high percentage of glass in the metal phase, requiring further separation. (2) The main melting and solidification system setup was established. A number of melting and solidification tests were conducted. (3) Temperature distribution, solidification patterns, and flow field in the molten metal pool were simulated numerically for the solidification processes of molten aluminum and iron steel. (4) Initial designs of the laboratory-scale DCS and CS technologies were also completed. The principal demonstration separation units were constructed. (5) An application for a patent for an innovative liquid-liquid separation technology was submitted and is pending.

  5. Multi-point injection demonstration for solidification of shallow buried waste at Oak Ridge Reservation, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The multi-point injection (MPI) technology is a precision, high-velocity jetting process for the in situ delivery of various agents to treat radiological and/or chemical wastes. A wide variety of waste forms can be treated, varying from heterogeneous waste dumped into shallow burial trenches to contaminated soils consisting of sands/gravels, silts/clays and soft rock. The robustness of the MPI system is linked to its broad range of applications which vary from in situ waste treatment to creation of both vertical and horizontal barriers. The only major constraint on the type of in situ treatment which can be delivered by the NTI system is that agents must be in a slurry form.

  6. Reduction of68Ge activity containing liquid waste from68Ga PET chemistry in nuclear medicine and radiopharmacy by solidification.

    Science.gov (United States)

    de Blois, Erik; Chan, Ho Sze; Roy, Kamalika; Krenning, Eric P; Breeman, Wouter A P

    PET with 68 Ga from the TiO 2 - or SnO 2 - based 68 Ge/ 68 Ga generators is of increasing interest for PET imaging in nuclear medicine. In general, radionuclidic purity ( 68 Ge vs. 68 Ga activity) of the eluate of these generators varies between 0.01 and 0.001%. Liquid waste containing low amounts of 68 Ge activity is produced by eluting the 68 Ge/ 68 Ga generators and residues from PET chemistry. Since clearance level of 68 Ge activity in waste may not exceed 10 Bq/g, as stated by European Directive 96/29/EURATOM, our purpose was to reduce 68 Ge activity in solution from >10 kBq/g to waste. Most efficient method to reduce the 68 Ge activity is by sorption of TiO 2 or Fe 2 O 3 and subsequent centrifugation. The required 10 Bq per mL level of 68 Ge activity in waste was reached by Fe 2 O 3 logarithmically, whereas with TiO 2 asymptotically. The procedure with Fe 2 O 3 eliminates ≥90% of the 68 Ge activity per treatment. Eventually, to simplify the processing a recirculation system was used to investigate 68 Ge activity sorption on TiO 2 , Fe 2 O 3 or Zeolite. Zeolite was introduced for its high sorption at low pH, therefore 68 Ge activity containing waste could directly be used without further interventions. 68 Ge activity containing liquid waste at different HCl concentrations (0.05-1.0 M HCl), was recirculated at 1 mL/min. With Zeolite in the recirculation system, 68 Ge activity showed highest sorption.

  7. Treatment of radioactive waste salt by using synthetic silica-based phosphate composite for de-chlorination and solidification

    Science.gov (United States)

    Cho, In-Hak; Park, Hwan-Seo; Lee, Ki-Rak; Choi, Jung-Hun; Kim, In-Tae; Hur, Jin Mok; Lee, Young-Seak

    2017-09-01

    In the radioactive waste management, waste salts as metal chloride generated from a pyrochemical process to recover uranium and transuranic elements are one of problematic wastes due to their intrinsic properties such as high volatility and low compatibility with conventional glasses. This study reports a method to stabilize and solidify LiCl waste via de-chlorination using a synthetic composite, U-SAP (SiO2-Al2O3-B2O3-Fe2O3-P2O5) prepared by a sol-gel process. The composite was reacted with alkali metal elements to produce some metal aluminosilicates, aluminophosphates or orthophosphate as a crystalline or amorphous compound. Different from the original SAP (SiO2-Al2O3-P2O5), the reaction product of U-SAP could be successfully fabricated as a monolithic wasteform without a glassy binder at a proper reaction/consolidation condition. From the results of the FE-SEM, FT-IR and MAS-NMR analysis, it could be inferred that the Si-rich phase and P-rich phase as a glassy grains would be distributed in tens of nm scale, where alkali metal elements would be chemically interacted with Si-rich or P-rich region in the virgin U-SAP composite and its products was vitrified into a silicate or phosphate glass after a heat-treatment at 1150 °C. The PCT-A (Product Consistency Test, ASTM-1208) revealed that the mass loss of Cs and Sr in the U-SAP wasteform had a range of 10-3∼10-1 g/m2 and the leach-resistance of the U-SAP wasteform was comparable to other conventional wasteforms. From the U-SAP method, LiCl waste salt was effectively stabilized and solidified with high waste loading and good leach-resistance.

  8. SOLIDIFICATION OF THE HANFORD LAW WASTE STREAM PRODUCED AS A RESULT OF NEAR-TANK CONTINUOUS SLUDGE LEACHING AND SODIUM HYDROXIDE RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    Reigel, M.; Johnson, F.; Crawford, C.; Jantzen, C.

    2011-09-20

    The U.S. Department of Energy (DOE), Office of River Protection (ORP), is responsible for the remediation and stabilization of the Hanford Site tank farms, including 53 million gallons of highly radioactive mixed wasted waste contained in 177 underground tanks. The plan calls for all waste retrieved from the tanks to be transferred to the Waste Treatment Plant (WTP). The WTP will consist of three primary facilities including pretreatment facilities for Low Activity Waste (LAW) to remove aluminum, chromium and other solids and radioisotopes that are undesirable in the High Level Waste (HLW) stream. Removal of aluminum from HLW sludge can be accomplished through continuous sludge leaching of the aluminum from the HLW sludge as sodium aluminate; however, this process will introduce a significant amount of sodium hydroxide into the waste stream and consequently will increase the volume of waste to be dispositioned. A sodium recovery process is needed to remove the sodium hydroxide and recycle it back to the aluminum dissolution process. The resulting LAW waste stream has a high concentration of aluminum and sodium and will require alternative immobilization methods. Five waste forms were evaluated for immobilization of LAW at Hanford after the sodium recovery process. The waste forms considered for these two waste streams include low temperature processes (Saltstone/Cast stone and geopolymers), intermediate temperature processes (steam reforming and phosphate glasses) and high temperature processes (vitrification). These immobilization methods and the waste forms produced were evaluated for (1) compliance with the Performance Assessment (PA) requirements for disposal at the IDF, (2) waste form volume (waste loading), and (3) compatibility with the tank farms and systems. The iron phosphate glasses tested using the product consistency test had normalized release rates lower than the waste form requirements although the CCC glasses had higher release rates than the

  9. Final waste forms project: Performance criteria for phase I treatability studies

    Energy Technology Data Exchange (ETDEWEB)

    Gilliam, T.M. [Oak Ridge National Lab., TN (United States); Hutchins, D.A. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States); Chodak, P. III [Massachusetts Institute of Technology (United States)

    1994-06-01

    This document defines the product performance criteria to be used in Phase I of the Final Waste Forms Project. In Phase I, treatability studies will be performed to provide {open_quotes}proof-of-principle{close_quotes} data to establish the viability of stabilization/solidification (S/S) technologies. This information is required by March 1995. In Phase II, further treatability studies, some at the pilot scale, will be performed to provide sufficient data to allow treatment alternatives identified in Phase I to be more fully developed and evaluated, as well as to reduce performance uncertainties for those methods chosen to treat a specific waste. Three main factors influence the development and selection of an optimum waste form formulation and hence affect selection of performance criteria. These factors are regulatory, process-specific, and site-specific waste form standards or requirements. Clearly, the optimum waste form formulation will require consideration of performance criteria constraints from each of the three categories. Phase I will focus only on the regulatory criteria. These criteria may be considered the minimum criteria for an acceptable waste form. In other words, a S/S technology is considered viable only if it meet applicable regulatory criteria. The criteria to be utilized in the Phase I treatability studies were primarily taken from Environmental Protection Agency regulations addressed in 40 CFR 260 through 265 and 268; and Nuclear Regulatory Commission regulations addressed in 10 CFR 61. Thus the majority of the identified criteria are independent of waste form matrix composition (i.e., applicable to cement, glass, organic binders etc.).

  10. Reduction of 68Ge activity containing liquid waste from 68Ga PET chemistry in nuclear medicine and radiopharmacy by solidification

    NARCIS (Netherlands)

    E. de Blois (Erik); H.S. Chan (Ho Sze); K. Roy (Kamalika); E.P. Krenning (Eric); W.A.P. Breeman (Wouter)

    2011-01-01

    textabstractPET with68Ga from the TiO2- or SnO2- based68Ge/68Ga generators is of increasing interest for PET imaging in nuclear medicine. In general, radionuclidic purity (68Ge vs.68Ga activity) of the eluate of these generators varies between 0.01 and 0.001%. Liquid waste containing low amounts

  11. Concentration and solidification of liquid radioactive wastes. Laboratory studies; Concentracion e inmovilizacion de residuos liquidos radiactivos. Estudio de Laboratorio

    Energy Technology Data Exchange (ETDEWEB)

    Nuche Vazquez F.; Lora Soria, F. de

    1969-07-01

    Bench scale runs on concentration of intermediate level radioactive wastes, and incorporation of the concentrates in asphalt, are described. The feasibility of the process has been demonstrated, with a maximum incorporation of 60 percent of salts into the asphaltic matrix and a volume reduction factor of 10. (Author) 14 refs.

  12. Dechlorination/Solidification of LiCl waste by using a synthetic inorganic composite with different compositions

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Na Young; Cho, In Hak; Park, Hwan Seo; Ahn, Do Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-09-15

    Waste salt generated from a pyro-processing for the recovery of uranium and transuranic elements has high volatility at vitrification temperature and low compatibility in conventional waste glasses. For this reason, KAERI (Korea Atomic Energy Research Institute) suggested a new method to de-chlorinate waste salt by using an inorganic composite named SAP (SiO{sub 2}-Al{sub 2}O{sub 3}-P{sub 2}O{sub 5}). In this study, the de-chlorination behavior of waste salt and the microstructure of consolidated form were examined by adding B{sub 2}O{sub 3} and Fe{sub 2}O{sub 3} to the original SAP composition. De-chlorination behavior of metal chloride waste was slightly changed with given compositions, compared with that of original SAP. In the consolidated forms, the phase separation between Si-rich phase and P-rich phase decreases with the amount of Al{sub 2}O{sub 3} or B{sub 2}O{sub 3} as a connecting agent between Si and P-rich phase. The results of PCT (Product Consistency Test) indicated that the leach-resistance of consolidated forms out of reference composition was lowered, even though the leach-resistance was higher than that of EA (Environmental Assessment) glass. From these results, it could be inferred that the change in the content of Al or B in U-SAP affected the microstructure and leach-resistance of consolidated form. Further studies related with correlation between composition and characteristics of wasteform are required for a better understanding.

  13. SECONDARY WASTE MANAGEMENT STRATEGY FOR EARLY LOW ACTIVITY WASTE TREATMENT

    Energy Technology Data Exchange (ETDEWEB)

    TW, CRAWFORD

    2008-07-17

    This study evaluates parameters relevant to River Protection Project secondary waste streams generated during Early Low Activity Waste operations and recommends a strategy for secondary waste management that considers groundwater impact, cost, and programmatic risk. The recommended strategy for managing River Protection Project secondary waste is focused on improvements in the Effiuent Treatment Facility. Baseline plans to build a Solidification Treatment Unit adjacent to Effluent Treatment Facility should be enhanced to improve solid waste performance and mitigate corrosion of tanks and piping supporting the Effiuent Treatment Facility evaporator. This approach provides a life-cycle benefit to solid waste performance and reduction of groundwater contaminants.

  14. Sets of Reports and Articles Regarding Cement Wastes Forms Containing Alpha Emitters that are Potentially Useful for Development of Russian Federation Waste Treatment Processes for Solidification of Weapons Plutonium MOX Fuel Fabrication Wastes for

    Energy Technology Data Exchange (ETDEWEB)

    Jardine, L J

    2003-06-12

    This is a set of nine reports and articles that were kindly provided by Dr. Christine A. Langton from the Savannah River Site (SRS) to L. J. Jardine LLNL in June 2003. The reports discuss cement waste forms and primarily focus on gas generation in cement waste forms from alpha particle decays. However other items such as various cement compositions, cement product performance test results and some cement process parameters are also included. This set of documents was put into this Lawrence Livermore National Laboratory (LLNL) releasable report for the sole purpose to provide a set of documents to Russian technical experts now beginning to study cement waste treatment processes for wastes from an excess weapons plutonium MOX fuel fabrication facility. The intent is to provide these reports for use at a US RF Experts Technical Meeting on: the Management of Wastes from MOX Fuel Fabrication Facilities, in Moscow July 9-11, 2003. The Russian experts should find these reports to be very useful for their technical and economic feasibility studies and the supporting R&D activities required to develop acceptable waste treatment processes for use in Russia as part of the ongoing Joint US RF Plutonium Disposition Activities.

  15. Alternative High-Performance Ceramic Waste Forms

    Energy Technology Data Exchange (ETDEWEB)

    Sundaram, S. K. [Alfred Univ., NY (United States)

    2017-02-01

    This final report (M5NU-12-NY-AU # 0202-0410) summarizes the results of the project titled “Alternative High-Performance Ceramic Waste Forms,” funded in FY12 by the Nuclear Energy University Program (NEUP Project # 12-3809) being led by Alfred University in collaboration with Savannah River National Laboratory (SRNL). The overall focus of the project is to advance fundamental understanding of crystalline ceramic waste forms and to demonstrate their viability as alternative waste forms to borosilicate glasses. We processed single- and multiphase hollandite waste forms based on simulated waste streams compositions provided by SRNL based on the advanced fuel cycle initiative (AFCI) aqueous separation process developed in the Fuel Cycle Research and Development (FCR&D). For multiphase simulated waste forms, oxide and carbonate precursors were mixed together via ball milling with deionized water using zirconia media in a polyethylene jar for 2 h. The slurry was dried overnight and then separated from the media. The blended powders were then subjected to melting or spark plasma sintering (SPS) processes. Microstructural evolution and phase assemblages of these samples were studied using x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion analysis of x-rays (EDAX), wavelength dispersive spectrometry (WDS), transmission electron spectroscopy (TEM), selective area x-ray diffraction (SAXD), and electron backscatter diffraction (EBSD). These results showed that the processing methods have significant effect on the microstructure and thus the performance of these waste forms. The Ce substitution into zirconolite and pyrochlore materials was investigated using a combination of experimental (in situ XRD and x-ray absorption near edge structure (XANES)) and modeling techniques to study these single phases independently. In zirconolite materials, a transition from the 2M to the 4M polymorph was observed with increasing Ce content. The resulting

  16. Radioactive Waste Management Complex performance assessment: Draft

    Energy Technology Data Exchange (ETDEWEB)

    Case, M.J.; Maheras, S.J.; McKenzie-Carter, M.A.; Sussman, M.E.; Voilleque, P.

    1990-06-01

    A radiological performance assessment of the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory was conducted to demonstrate compliance with appropriate radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the general public. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the general public via air, ground water, and food chain pathways. Projections of doses were made for both offsite receptors and individuals intruding onto the site after closure. In addition, uncertainty analyses were performed. Results of calculations made using nominal data indicate that the radiological doses will be below appropriate radiological criteria throughout operations and after closure of the facility. Recommendations were made for future performance assessment calculations.

  17. Waste-Form Development Program. Annual progress report, October 1981-September 1982

    Energy Technology Data Exchange (ETDEWEB)

    Neilson, R.M. Jr.; Colombo, P.

    1982-09-01

    Low-level wastes (LLW) at nuclear facilities have traditionally been solidified using portland cement (with and without additives). Urea-formaldehyde has been used for LLW solidification while bitumen (asphalt) and thermosetting polymers will be applied to domestic wastes in the near future. Operational difficulties have been observed with each of these solidification agents. Such difficulties include incompatibility with waste constitutents inhibiting solidification, premature setting, free standing water and fires. Some specific waste types have proven difficult to solidify with one or more of the contemporary agents. Similar problems are also anticipated for the solidification of new wastes, which are generated using advanced volume reduction technologies, and with the application of additional agents which may be introduced in the near future for the solidification of LLW. In the Waste Form Development program, contemporary solidification agents are being investigated relative to their potential applications to major fuel cycle and non-fuel cycle LLW streams. The range of conditions under which these solidification agents can be satisfactorily applied to specific LLW streams is being determined. These studies are primarily directed towards defining operating parameters for both improved solidification of problem wastes such as ion exchange resins, organic liquids and oils for which prevailing processes, as currently employed, appear to be inadequate, and solidification of new LLW streams including high solids content evaporator concentrates, dry solids, and incinerator ash generated from advanced volume reduction technologies. Solidified waste forms are tested and evaluated to demonstrate compliance with waste form performance and shallow land burial (SLB) acceptance criteria and transportation requirements (both as they currently exist and as they are anticipated to be modified with time).

  18. Polymer Solidification Technology - Technical Issues and Challenges

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Charles [Diversified Technologies Services, Inc., Knoxville (United States); Kim, Juyoul [Seoul National Univ., Seoul (Korea, Republic of)

    2010-07-01

    Many factors come into play, most of which are discovered and resolved only during full-scale solidification testing of each of the media commonly used in nuclear power plants. Each waste stream is unique, and must be addressed accordingly. This testing process is so difficult that Diversified's Vinyl Ester Styrene and Advanced Polymer Solidification are the only two approved processes in the United States today. This paper summarizes a few of the key obstacles that must be overcome to achieve a reliable, repeatable process for producing an approved Stable Class B and C waste form. Before other solidification and encapsulation technologies can be considered compliant with the requirements of a Stable waste form, the tests, calculations and reporting discussed above must be conducted for both the waste form and solidification process used to produce the waste form. Diversified's VERI{sup TM} and APS{sup TM} processes have gained acceptance in the UK. These processes have also been approved and gained acceptance in the U. S. because we have consistently overcome technical hurdles to produce a complaint product. Diversified Technologies processes are protected intellectual property. In specific instances, we have patents pending on key parts of our process technology.

  19. Solidification of low-volume power plant sludges. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bell, N.E.; Halverson, M.A.; Mercer, B.M.

    1981-12-01

    A literature review was conducted to obtain information on the status of hazardous waste solidification technology and application of this technology to low-volume power plant waste sludges. Because of scarcity of sludge composition data, anticipated major components were identified primarily by chemical reactions that are known to occur during treatment of specific wastewaters. Chemical and physical properties of these sludges were critically analyzed for compatibility with several types of commercially available solidification processes. The study pointed out the need for additional information on the nature of these sludges, especially leaching characteristics and the presence of substances that will interfere with solidification processes. Laboratory studies were recommended for evaluation of solidification process which have the greatest potential for converting hazardous low-volume sludges to non-hazardous waste forms.

  20. Fundamental Metallurgy of Solidification

    DEFF Research Database (Denmark)

    Tiedje, Niels

    2004-01-01

    The text takes the reader through some fundamental aspects of solidification, with focus on understanding the basic physics that govern solidification in casting and welding. It is described how the first solid is formed and which factors affect nucleation. It is described how crystals grow from ...

  1. Advances in Solidification Processing

    Indian Academy of Sciences (India)

    Unknown

    Advances in Solidification Processing. FOREWORD. Solidification phenomena are the heart of most of ... Besides these, the new advances in the understanding of the process have led to the ... steel chemistry on the thermo-mechanical state of solidifying strands is discussed. Finally, control of continuous casting of stainless ...

  2. Development and Performance Evaluation of a Low Cost Waste ...

    African Journals Online (AJOL)

    The design, development and performance evaluation of a low cost waste-water treatment plant had been carried out. The aim was to harness the usefulness of waste-waters from residential, institutional and commercial sources. The facultative lagoon method of waste-water treatment was adopted. Biological analysis of ...

  3. Secondary Waste Cementitious Waste Form Data Package for the Integrated Disposal Facility Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, Kirk J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Serne, R Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cozzi, Alex D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-05-16

    A review of the most up-to-date and relevant data currently available was conducted to develop a set of recommended values for use in the Integrated Disposal Facility (IDF) performance assessment (PA) to model contaminant release from a cementitious waste form for aqueous wastes treated at the Hanford Effluent Treatment Facility (ETF). This data package relies primarily upon recent data collected on Cast Stone formulations fabricated with simulants of low-activity waste (LAW) and liquid secondary wastes expected to be produced at Hanford. These data were supplemented, when necessary, with data developed for saltstone (a similar grout waste form used at the Savannah River Site). Work is currently underway to collect data on cementitious waste forms that are similar to Cast Stone and saltstone but are tailored to the characteristics of ETF-treated liquid secondary wastes. Recommended values for key parameters to conduct PA modeling of contaminant release from ETF-treated liquid waste are provided.

  4. Evolution of solidification texture during additive manufacturing

    Science.gov (United States)

    Wei, H. L.; Mazumder, J.; DebRoy, T.

    2015-01-01

    Striking differences in the solidification textures of a nickel based alloy owing to changes in laser scanning pattern during additive manufacturing are examined based on theory and experimental data. Understanding and controlling texture are important because it affects mechanical and chemical properties. Solidification texture depends on the local heat flow directions and competitive grain growth in one of the six preferred growth directions in face centered cubic alloys. Therefore, the heat flow directions are examined for various laser beam scanning patterns based on numerical modeling of heat transfer and fluid flow in three dimensions. Here we show that numerical modeling can not only provide a deeper understanding of the solidification growth patterns during the additive manufacturing, it also serves as a basis for customizing solidification textures which are important for properties and performance of components. PMID:26553246

  5. Advances in Solidification Processing

    Directory of Open Access Journals (Sweden)

    Hugo F. Lopez

    2015-08-01

    Full Text Available Melt solidification is the shortest and most viable route to obtain components, starting from the design to the finished products. Hence, a sound knowledge of the solidification of metallic materials is essential for the development of advanced structural metallic components that drive modern technological societies. As a result, there have been innumerable efforts and full conferences dedicated to this important subject [1–6]. In addition, there are various scientific journals fully devoted to investigating the various aspects which give rise to various solidification microstructures [7–9]. [...

  6. Minority carrier lifetime evaluation of periphery edge region in high-performance multicrystalline ingot produced by seed-assisted directional solidification

    Science.gov (United States)

    Li, Zhong; Li, Jia-Dan; Zhuang, Lin; Hong, Rui-Jiang

    2017-10-01

    A high-performance multicrystalline silicon (mc-Si) ingot was produced by seed-assisted directional solidification, and the minority carrier lifetime of the periphery edge region was evaluated. The defects and impurities in the periphery edge region of the silicon wafers were systematically studied with photoluminescence (PL) imaging, minority carrier lifetime mapping, and Fourier transform infrared (FTIR) spectroscopy. Their relationships with the minority carrier lifetime were investigated. The concentration of substitutional carbon, interstitial oxygen, and dislocation clusters is not directly correlated with the low minority carrier lifetime of the edge zone of the mc-Si ingot. Inhomogeneous grain size distribution and contamination with iron impurities were demonstrated to be the main factors affecting the low minority carrier lifetime. By controlling the impurities and improving the grain size distribution, a modified furnace was designed and a higher-quality mc-Si ingot was manufactured.

  7. Performance Of The Akosombo Waste Stabilization Ponds In Ghana ...

    African Journals Online (AJOL)

    A study was conducted to determine the treatment performance of the Akosombo waste stabilization ponds and the effect of seasonal changes on the final effluent quality. The waste water quality parameters adopted to determine the treatment performance were suspended solids (SS), biochemical oxygen demand (BOD), ...

  8. Solidification and casting

    CERN Document Server

    Cantor, Brian

    2002-01-01

    INDUSTRIAL PERSPECTIVEDirect chillcasting of aluminium alloysContinuous casting of aluminium alloysContinuous casting of steelsCastings in the automotive industryCast aluminium-silicon piston alloysMODELLING AND SIMULATIONModelling direct chill castingMold filling simulation of die castingThe ten casting rulesGrain selection in single crystal superalloy castingsDefects in aluminium shape castingPattern formation during solidificationPeritectic solidificationSTRUCTURE AND DEFECTSHetergeneous nucleation in aluminium alloysCo

  9. Waste forms technology and performance: final report

    National Research Council Canada - National Science Library

    Committee on Waste Forms Technology and Performance; National Research Council

    2011-01-01

    "The Department of Energy's Office of Environmental Management (DOE-EM) is responsible for cleaning up radioactive waste and environmental contamination resulting from five decades of nuclear weapons production and testing...

  10. A study of separation and solidification of group II nuclides in waste salt delivered from the pyrochemical process of used nuclear fuel

    Science.gov (United States)

    Eun, H. C.; Choi, J. H.; Kim, N. Y.; Lee, T. K.; Han, S. Y.; Jang, S. A.; Kim, T. J.; Park, H. S.; Ahn, D. H.

    2017-08-01

    If group II nuclides, which contain high heat-generative elements, in waste salt are fabricated into a waste form rich in group II nuclides, the waste form can be used in radionuclide thermoelectric generator applications. For this reason, the separation of group II nuclides in salt (LiCl, LiCl-KCl) was conducted, after which a waste form rich in them was fabricated. In this study, group II nuclide chlorides in salt were effectively separated into a carbonate or oxychloride form, and the separated nuclides were successfully fabricated into a homogenous and stable glass waste form with high contents (45-50 wt%) of these nuclides.

  11. Liquid secondary waste. Waste form formulation and qualification

    Energy Technology Data Exchange (ETDEWEB)

    Cozzi, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dixon, K. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hill, K. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); King, W. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nichols, R. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-03-01

    The Hanford Site Effluent Treatment Facility (ETF) currently treats aqueous waste streams generated during Site cleanup activities. When the Hanford Tank Waste Treatment and Immobilization Plant (WTP) begins operations, a liquid secondary waste (LSW) stream from the WTP will need to be treated. The volume of effluent for treatment at the ETF will increase significantly. Washington River Protection Solutions is implementing a Secondary Liquid Waste Immobilization Technology Development Plan to address the technology needs for a waste form and solidification process to treat the increased volume of waste planned for disposal at the Integrated Disposal Facility IDF). Waste form testing to support this plan is composed of work in the near term to demonstrate the waste form will provide data as input to a performance assessment (PA) for Hanford’s IDF.

  12. Performance Evaluation of Concrete using Marble Mining Waste

    Directory of Open Access Journals (Sweden)

    Kore Sudarshan Dattatraya

    2016-12-01

    Full Text Available A huge amount waste (approximately 60% is generated during mining and processing in marble industries. Such waste can be best utilized in infrastructure development works. Coarse aggregate 75% by weight was replaced by aggregate obtained from marble mining waste. The impact of marble waste as a partial replacement for conventional coarse aggregate on the properties of concrete mixes such as workability, compressive strength, permeability, abrasion, etc. was evaluated. The test results revealed that the compressive strength was comparable to that of control concrete. Other properties such as workability of concrete increased, water absorption reduced by 17%, and resistance to abrasion was marginally increased by 2% as compared to that of control concrete. Ultrasonic pulse velocity and FTIR results show improvement in quality of concrete with crushed marble waste. From the TGA analysis it was confirmed that, aggregate produced from marble waste shows better performance under elevated temperature than that of conventional aggregates.

  13. Challenges when performing economic optimization of waste treatment: A review

    Energy Technology Data Exchange (ETDEWEB)

    Juul, N., E-mail: njua@dtu.dk [DTU Management, Risø Campus, Technical University of Denmark (Denmark); Münster, M., E-mail: maem@dtu.dk [DTU Management, Risø Campus, Technical University of Denmark (Denmark); Ravn, H., E-mail: hans.ravn@aeblevangen.dk [RAM-løse edb, Æblevangen 55, 2765 Smørum (Denmark); Söderman, M. Ljunggren, E-mail: maria.ljunggren@chalmers.se [Energy and Environment, Chalmers University of Technology, Gothenburg (Sweden); IVL Swedish Environmental Research Institute, Gothenburg (Sweden)

    2013-09-15

    Highlights: • Review of main optimization tools in the field of waste management. • Different optimization methods are applied. • Different fractions are analyzed. • There is focus on different parameters in different geographical regions. • More research is needed which encompasses both recycling and energy solutions. - Abstract: Strategic and operational decisions in waste management, in particular with respect to investments in new treatment facilities, are needed due to a number of factors, including continuously increasing amounts of waste, political demands for efficient utilization of waste resources, and the decommissioning of existing waste treatment facilities. Optimization models can assist in ensuring that these investment strategies are economically feasible. Various economic optimization models for waste treatment have been developed which focus on different parameters. Models focusing on transport are one example, but models focusing on energy production have also been developed, as well as models which take into account a plant’s economies of scale, environmental impact, material recovery and social costs. Finally, models combining different criteria for the selection of waste treatment methods in multi-criteria analysis have been developed. A thorough updated review of the existing models is presented, and the main challenges and crucial parameters that need to be taken into account when assessing the economic performance of waste treatment alternatives are identified. The review article will assist both policy-makers and model-developers involved in assessing the economic performance of waste treatment alternatives.

  14. Secondary Waste Cast Stone Waste Form Qualification Testing Plan

    Energy Technology Data Exchange (ETDEWEB)

    Westsik, Joseph H.; Serne, R. Jeffrey

    2012-09-26

    The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the 56 million gallons of radioactive waste stored in 177 underground tanks at the Hanford Site. The WTP includes a pretreatment facility to separate the wastes into high-level waste (HLW) and low-activity waste (LAW) fractions for vitrification and disposal. The LAW will be converted to glass for final disposal at the Integrated Disposal Facility (IDF). Cast Stone – a cementitious waste form, has been selected for solidification of this secondary waste stream after treatment in the ETF. The secondary-waste Cast Stone waste form must be acceptable for disposal in the IDF. This secondary waste Cast Stone waste form qualification testing plan outlines the testing of the waste form and immobilization process to demonstrate that the Cast Stone waste form can comply with the disposal requirements. Specifications for the secondary-waste Cast Stone waste form have not been established. For this testing plan, Cast Stone specifications are derived from specifications for the immobilized LAW glass in the WTP contract, the waste acceptance criteria for the IDF, and the waste acceptance criteria in the IDF Permit issued by the State of Washington. This testing plan outlines the testing needed to demonstrate that the waste form can comply with these waste form specifications and acceptance criteria. The testing program must also demonstrate that the immobilization process can be controlled to consistently provide an acceptable waste form product. This testing plan also outlines the testing needed to provide the technical basis for understanding the long-term performance of the waste form in the disposal environment. These waste form performance data are needed to support performance assessment analyses of the long-term environmental impact of the secondary-waste Cast Stone waste form in the IDF

  15. Waste form development program. Annual report, October 1982-September 1983

    Energy Technology Data Exchange (ETDEWEB)

    Colombo, P.; Kalb, P.D.; Fuhrmann, M.

    1983-09-01

    This report provides a summary of the work conducted for the Waste Form Development/Test Program at Brookhaven National Laboratory in FY 1983 under the sponsorship of the US Department of Energy's Low-Level Waste Management Program. The primary focus of this work is the investigation of new solidification agents which will provide improved immobilization of low-level radioactive wastes in an efficient, cost-effective manner. A working set of preliminary waste form evaluation criteria which could impact upon the movement of radionuclides in the disposal environment was developed. The selection of potential solidification agents for further investigation is described. Two thermoplastic materials, low-density polyethylene and a modified sulfur cement were chosen as primary candidates for further study. Three waste types were selected for solidification process development and waste form property evaluation studies which represent both new volume reduction wastes (dried evaporator concentrates and incinerator ash) and current problem wastes (ion exchange resins). Preliminary process development scoping studies were conducted to verify the compatibility of selected solidification agents and waste types and the potential for improved solidification. Waste loadings of 60 wt % Na/sub 2/SO/sub 4/, 25 wt % H/sub 3/BO/sub 3/, 25 wt % incinerator ash and 50 wt % dry ion exchange resin were achieved using low density polyethylene as a matrix material. Samples incorporating 65 wt % Na/sub 2/SO/sub 4/, 40 wt % H/sub 3/BO/sub 3/, 20 wt % incinerator ash and 40 wt % dry ion exchange resin were successfully solidified in modified sulfur cement. Additional improvements are expected for both matrix materials as process parameters are optimized. Several preliminary property evaluation studies were performed to provide the basis for an initial assessment of waste form acceptability. These included a two-week water immersion test and compressive load testing.

  16. Feasibility study on the solidification of liquid low-level radioactive mixed waste in the inactive tank system at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Trussell, S. (Texas A and M Univ., College Station, TX (United States). Dept. of Civil Engineering); Spence, R.D. (Oak Ridge National Lab., TN (United States))

    1993-01-01

    A literature survey was conducted to help determine the feasibility of solidifying a liquid low-level radioactive mixed waste in the inactive tank system at Oak Ridge National Laboratory (ORNL). The goal of this report is to facilitate a decision on the disposition of these wastes by identifying any waste constituents that might (1) compromise the strength or stability of the waste form or (2) be highly leachable. Furthermore, its goal is to identify ways to circumvent interferences and to decrease the leachability of the waste constituents. This study has sought to provide an understanding of inhibition of cement set by identifying the fundamental chemical mechanisms by which this inhibition takes place. From this fundamental information, it is possible to draw some conclusions about the potential effects of waste constituents, even in the absence of particular studies on specific compounds.

  17. Performance Demonstration Program Plan for Nondestructive Assay of Drummed Wastes for the TRU Waste Characterization Program

    Energy Technology Data Exchange (ETDEWEB)

    Carlsbad Field Office

    2005-08-03

    The Performance Demonstration Program (PDP) for Nondestructive Assay (NDA) is a test program designed to yield data on measurement system capability to characterize drummed transuranic (TRU) waste generated throughout the Department of Energy (DOE) complex. The tests are conducted periodically and provide a mechanism for the independent and objective assessment of NDA system performance and capability relative to the radiological characterization objectives and criteria of the Office of Characterization and Transportation (OCT). The primary documents requiring an NDA PDP are the Waste Acceptance Criteria for the Waste Isolation Pilot Plant (WAC), which requires annual characterization facility participation in the PDP, and the Quality Assurance Program Document (QAPD). This NDA PDP implements the general requirements of the QAPD and applicable requirements of the WAC. Measurement facilities must demonstrate acceptable radiological characterization performance through measurement of test samples comprised of pre-specified PDP matrix drum/radioactive source configurations. Measurement facilities are required to analyze the NDA PDP drum samples using the same procedures approved and implemented for routine operational waste characterization activities. The test samples provide an independent means to assess NDA measurement system performance and compliance per criteria delineated in the NDA PDP Plan. General inter-comparison of NDA measurement system performance among DOE measurement facilities and commercial NDA services can also be evaluated using measurement results on similar NDA PDP test samples. A PDP test sample consists of a 55-gallon matrix drum containing a waste matrix type representative of a particular category of the DOE waste inventory and nuclear material standards of known radionuclide and isotopic composition typical of DOE radioactive material. The PDP sample components are made available to participating measurement facilities as designated by the

  18. Application of coal combustion residues to the stabilization/solidification of industrial wastes (IRIS); Desarrollo de un Proceso, a Escala Piloto de Inertizacion de Residuos Industriales con Cenizas Volantes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    Stabilization/solidification (S/S) processes, also called inertization processes, are a group of techniques which employ additives to reduce the mobility of the hazardous components from the waste and make possible for the residue to be accepted for its disposal in a safe way. These processes, mainly applied to wastes that contain heavy metals (such as lead, zinc, cadminum, mercury, copper, nickel, titanium, chromium-III, chromium-VI, arsenic,....) change the waste into a solid-like material in which the metals are trapped (nets and matrix) by physical or chemical links. The IRIS Project, carried out by AICIA through the ECSC Coal Programme with the participation of two industrial partners (Sevillana de Electricidad and EGMASA, a public-owned company for waste treatment), has developed, at pilot scale, a new S/S process for inorganic industrial wastes that uses great quantities of fly ash in the place of other more commonly used and expansive reagents. A pilot plant for 200 kg/h has been designed, built and operated. This facility has allowed to add improvements and scientific foundations to existing S/S technology. It has also allowed to obtain industrial scale parameters for fixed and portable plants. Experiencie have been mainly carried out using fly ash from high quality coals, but types of ash have been tested coming from coals with a greater calcium content, from fluidised bed combustion boilers and from desulphurisation processes, giving very suitable characteristics for their application to S/S processes. The addition of fly ash (up to 30%) in the IRIS process improves the results in comparison with the S/S processes that use only cement, because the final pH obtained (8-11) does not allow amphoteric metallic ions to escape in the leachate. The same as other S/S processes, IRIS can be applied also to wastes that contain certain metals (chromium-VI, arsenic, for example) with specific pre-treatments (redox, for example). The efficiency of the IRIS treatment

  19. Performance Demonstration Program Plan for Nondestructive Assay of Boxed Wastes for the TRU Waste Characterization Program

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2009-10-01

    Each testing and analytical facility performing waste characterization activities for the Waste Isolation Pilot Plant (WIPP) participates in the Performance Demonstration Program (PDP) to comply with the Transuranic Waste Acceptance Criteria for the Waste Isolation Pilot Plant (WAC) (DOE/WIPP-02-3122) and the Quality Assurance Program Document (QAPD) (CBFO-94-1012). The PDP serves as a quality control check for data generated in the characterization of waste destined for WIPP. Single-blind audit samples are prepared and distributed to each of the facilities participating in the PDP. Different PDPs evaluate the analyses of simulated headspace gases (HSGs), constituents of the Resource Conservation and Recovery Act (RCRA), and transuranic (TRU) radionuclides using nondestructive assay (NDA) techniques.

  20. Performance Demonstration Program Plan for Nondestructive Assay of Drummed Wastes for the TRU Waste Characterization Program

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    2009-04-01

    Each testing and analytical facility performing waste characterization activities for the Waste Isolation Pilot Plant (WIPP) participates in the Performance Demonstration Program (PDP) to comply with the Transuranic Waste Acceptance Criteria for the Waste Isolation Pilot Plant (WAC) (DOE/WIPP-02-3122) and the Quality Assurance Program Document (QAPD) (CBFO-94-1012). The PDP serves as a quality control check for data generated in the characterization of waste destined for WIPP. Single blind audit samples are prepared and distributed to each of the facilities participating in the PDP. The PDP evaluates analyses of simulated headspace gases, constituents of the Resource Conservation and Recovery Act (RCRA), and transuranic (TRU) radionuclides using nondestructive assay (NDA) techniques.

  1. Performance of green waste biocovers for enhancing methane oxidation.

    Science.gov (United States)

    Mei, Changgen; Yazdani, Ramin; Han, Byunghyun; Mostafid, M Erfan; Chanton, Jeff; VanderGheynst, Jean; Imhoff, Paul

    2015-05-01

    Green waste aged 2 and 24months, labeled "fresh" and "aged" green waste, respectively, were placed in biocover test cells and evaluated for their ability to oxidize methane (CH4) under high landfill gas loading over a 15-month testing period. These materials are less costly to produce than green waste compost, yet satisfied recommended respiration requirements for landfill compost covers. In field tests employing a novel gas tracer to correct for leakage, both green wastes oxidized CH4 at high rates during the first few months of operation - 140 and 200g/m(2)/day for aged and fresh green waste, respectively. Biocover performance degraded during the winter and spring, with significant CH4 generated from anaerobic regions in the 60-80cm thick biocovers. Concurrently, CH4 oxidation rates decreased. Two previously developed empirical models for moisture and temperature dependency of CH4 oxidation in soils were used to test their applicability to green waste. Models accounted for 68% and 79% of the observed seasonal variations in CH4 oxidation rates for aged green waste. Neither model could describe similar seasonal changes for the less stable fresh green waste. This is the first field application and evaluation of these empirical models using media with high organic matter. Given the difficulty of preventing undesired CH4 generation, green waste may not be a viable biocover material for many climates and landfill conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Challenges when performing economic optimization of waste treatment: a review.

    Science.gov (United States)

    Juul, N; Münster, M; Ravn, H; Söderman, M Ljunggren

    2013-09-01

    Strategic and operational decisions in waste management, in particular with respect to investments in new treatment facilities, are needed due to a number of factors, including continuously increasing amounts of waste, political demands for efficient utilization of waste resources, and the decommissioning of existing waste treatment facilities. Optimization models can assist in ensuring that these investment strategies are economically feasible. Various economic optimization models for waste treatment have been developed which focus on different parameters. Models focusing on transport are one example, but models focusing on energy production have also been developed, as well as models which take into account a plant's economies of scale, environmental impact, material recovery and social costs. Finally, models combining different criteria for the selection of waste treatment methods in multi-criteria analysis have been developed. A thorough updated review of the existing models is presented, and the main challenges and crucial parameters that need to be taken into account when assessing the economic performance of waste treatment alternatives are identified. The review article will assist both policy-makers and model-developers involved in assessing the economic performance of waste treatment alternatives. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Solid waste drum array fire performance

    Energy Technology Data Exchange (ETDEWEB)

    Louie, R.L. [Westinghouse Hanford Co., Richland, WA (United States); Haecker, C.F. [Los Alamos Technical Associates, Inc., Kennewick, WA (United States); Beitel, J.J.; Gottuck, D.T.; Rhodes, B.T.; Bayier, C.L. [Hughes Associates, Inc., Baltimore, MD (United States)

    1995-09-01

    Fire hazards associated with drum storage of radioactively contaminated waste are a major concern in DOE waste storage facilities. This report is the second of two reports on fire testing designed to provide data relative to the propagation of a fire among storage drum arrays. The first report covers testing of individual drums subjected to an initiating fire and the development of the analytical methodology to predict fire propagation among storage drum arrays. This report is the second report, which documents the results of drum array fire tests. The purpose of the array tests was to confirm the analytical methodology developed by Phase I fire testing. These tests provide conclusive evidence that fire will not propagate from drum to drum unless an continuous fuel source other than drum contents is provided.

  4. Preliminary study on immobilization of buffing dust by solidification method in ceramic brick

    Science.gov (United States)

    Yuliansyah, Ahmad Tawfiequrrahman; Prasetya, Agus; Putra, Arif Eka; Satriawan, Humam Budi

    2017-11-01

    Leather-based industries generate a substantial amount of hazardous solid and liquid wastes in their process. One of the solid wastes is buffing dust, which is fine particulates containing fat, tanning, dyes and chromium. From 1 ton of leather processed, approximately 2-6 kg of buffing dust is generated. Chromium in the buffing dust is carcinogenic, so a proper handling is highly required. Solidification is a method commonly used to immobilize toxic material. Hence, the material is trapped in a matrix made of binding agents to minimize its mobility. However, a very small amount of the materials is sometimes released to the environment during storage. This study investigates leaching process of chromium from immobilized buffing dust in ceramic brick. Buffing dust, which contains chromium, is solidified by mixing it with clay at certain compositions and fired in a muffle furnace to produce a ceramic brick. Performance of the solidification process is evaluated by measuring the leaching of chromium in the leaching test. The results show that the solidification has significantly reduced the potential release of chromium to the environment. Higher of the firing temperature, less chromium is leached from ceramic brick. The chromium concentration of leachate water from 800°C brick is 0.376 ppm, while those from 850 and 900°C brick are 0.212 and 0.179 ppm respectively.

  5. Solidification microstructure development

    Indian Academy of Sciences (India)

    Unknown

    Primary manufacturing processes such as ingot casting, continuous casting, squeeze casting, pressure casting and atomization, and secondary manufacturing processes such as welding, soldering, brazing, cladding and sintering, involve solidification as an important stage of the process. Thermal and solutal conditions that ...

  6. The performance of blended conventional and novel binders in the in-situ stabilisation/solidification of a contaminated site soil.

    Science.gov (United States)

    Wang, Fei; Wang, Hailing; Jin, Fei; Al-Tabbaa, Abir

    2015-03-21

    This paper presents an investigation of the effects of novel binders and pH values on the effectiveness of the in-situ stabilisation/solidification technique in treating heavy metals and organic contaminated soils after 1.5-year treatment. To evaluate the performance of different binders, made ground soils of SMiRT site, upto 5 m depth, were stabilised/solidified with the triple auger system and cores were taken for laboratory testing after treatment. Twenty four different binders were used including Portland cement (PC), ground granulated blastfurnace slag (GGBS), pulverised fuel ash (PFA), MgO and zeolite. Unconfined compressive strength (UCS), leachate pH and the leachability of heavy metals and total organics were applied to study the behaviours of binders in treating site soils. Under various contaminant level and binder level, the results show that UCS values were 22-3476 kPa, the leachability of the total organics was in the range of 22-241 mg/l and the heavy metals was in the range of 0.002-0.225 mg/l. In addition, the combination of GGBS and MgO at a ratio of 9:1 shows better immobilisation efficiency in treating heavy metals and organic contaminated soils after 1.5-year treatment, and the binding mechanisms under different binders were also discussed in this paper. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Hanford low-level tank waste interim performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Mann, F.M.

    1996-09-16

    The Hanford Low-Level Tank Waste Interim Performance Assessment examines the long-term environmental and human health effects associated with the disposal of the low-level fraction of the Hanford single- and double-shell tank waste in the Hanford Site 200 East Area. This report was prepared as a good management practice to provide needed information about the relationship between the disposal system design and its performance as early as possible in the project cycle. The calculations in this performance assessment show that the disposal of the low-level fraction can meet environmental and health performance objectives.

  8. Hanford low-level tank waste interim performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Mann, F.M.

    1997-09-12

    The Hanford Low-Level Tank Waste Interim Performance Assessment examines the long-term environmental and human health effects associated with the disposal of the low-level fraction of the Hanford single and double-shell tank waste in the Hanford Site 200 East Area. This report was prepared as a good management practice to provide needed information about the relationship between the disposal system design and performance early in the disposal system project cycle. The calculations in this performance assessment show that the disposal of the low-level fraction can meet environmental and health performance objectives.

  9. SOLIDIFICATION CHARACTERISTIC OF TITANIUM CARBIDE PARTICULATE REINFORCED ALUMINIUM ALLOY MATRIX COMPOSITES

    Directory of Open Access Journals (Sweden)

    N. FATCHURROHMAN

    2012-04-01

    Full Text Available In this research solidification characteristic of metal matrix composites consisted of titanium carbide particulate reinforced aluminium-11.8% silicon alloy matrix is performed. Vortex mixing and permanent casting method are used as the manufacturing method to produce the specimens. Temperature measurements during the casting process are captured and solidification graphs are plotted to represent the solidification characteristic. The results show, as volume fraction of particulate reinforcement is increased, solidification time is faster. Particulate reinforcement promotes rapid solidification which will support finer grain size of the casting specimen. Hardness test is performed and confirmed that hardness number increased as more particulate are added to the system.

  10. Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC).

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter Andrew

    2011-12-01

    The objective of the U.S. Department of Energy Office of Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) is to provide an integrated suite of computational modeling and simulation (M&S) capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive-waste storage facility or disposal repository. Achieving the objective of modeling the performance of a disposal scenario requires describing processes involved in waste form degradation and radionuclide release at the subcontinuum scale, beginning with mechanistic descriptions of chemical reactions and chemical kinetics at the atomic scale, and upscaling into effective, validated constitutive models for input to high-fidelity continuum scale codes for coupled multiphysics simulations of release and transport. Verification and validation (V&V) is required throughout the system to establish evidence-based metrics for the level of confidence in M&S codes and capabilities, including at the subcontiunuum scale and the constitutive models they inform or generate. This Report outlines the nature of the V&V challenge at the subcontinuum scale, an approach to incorporate V&V concepts into subcontinuum scale modeling and simulation (M&S), and a plan to incrementally incorporate effective V&V into subcontinuum scale M&S destined for use in the NEAMS Waste IPSC work flow to meet requirements of quantitative confidence in the constitutive models informed by subcontinuum scale phenomena.

  11. Liquid secondary waste: Waste form formulation and qualification

    Energy Technology Data Exchange (ETDEWEB)

    Cozzi, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dixon, K. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hill, K. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nichols, R. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-07-31

    The Hanford Site Effluent Treatment Facility (ETF) currently treats aqueous waste streams generated during site cleanup activities. When the Hanford Tank Waste Treatment and Immobilization Plant (WTP) begins operations, including Direct Feed Low Activity Waste (DFLAW) vitrification, a liquid secondary waste (LSW) stream from the WTP will need to be treated. The volume of effluent for treatment at the ETF will increase significantly. The powdered salt waste form produced by the ETF will be replaced by a stabilized solidified waste form for disposal in Hanford’s Integrated Disposal Facility (IDF). Washington River Protection Solutions is implementing a Secondary Liquid Waste Immobilization Technology Development Plan to address the technology needs for a waste form and solidification process to treat the increased volume of waste planned for disposal at the IDF. Waste form testing to support this plan is composed of work in the near term to provide data as input to a performance assessment (PA) for Hanford’s IDF. In 2015, three Hanford Liquid Secondary Waste simulants were developed based on existing and projected waste streams. Using these waste simulants, fourteen mixes of Hanford Liquid Secondary Waste were prepared and tested varying the waste simulant, the water-to-dry materials ratio, and the dry materials blend composition.1 In FY16, testing was performed using a simulant of the EMF process condensate blended with the caustic scrubber—from the Low Activity Waste (LAW) melter—, processed through the ETF. The initial EMF-16 simulant will be based on modeling efforts performed to determine the mass balance of the ETF for the DFLAW.2 The compressive strength of all of the mixes exceeded the target of 3.4 MPa (500 psi) to meet the requirements identified as potential IDF Waste Acceptance Criteria in Table 1 of the Secondary Liquid Waste Immobilization Technology Development Plan.3 The hydraulic properties of the waste forms tested (hydraulic conductivity

  12. Validation of an in situ solidification/stabilization technique for hazardous barium and cyanide waste for safe disposal into a secured landfill.

    Science.gov (United States)

    Vaidya, Rucha; Kodam, Kisan; Ghole, Vikram; Surya Mohan Rao, K

    2010-09-01

    The aim of the present study was to devise and validate an appropriate treatment process for disposal of hazardous barium and cyanide waste into a landfill at a Common Hazardous Waste Treatment Storage Disposal Facility (CHWTSDF). The waste was generated during the process of hardening of steel components and contains cyanide (reactive) and barium (toxic) as major contaminants. In the present study chemical fixation of the contaminants was carried out. The cyanide was treated by alkali chlorination with calcium hypochlorite and barium by precipitation with sodium sulfate as barium sulfate. The pretreated mixture was then solidified and stabilized by binding with a combination of slag cement, ordinary Portland cement and fly ash, molded into blocks (5 x 5 x 5 cm) and cured for a period of 3, 7 and 28 days. The final experiments were conducted with 18 recipe mixtures of waste + additive:binder (W:B) ratios. The W:B ratios were taken as 80:20, 70:30 and 50:50. The optimum proportions of additives and binders were finalized on the basis of the criteria of unconfined compressive strength and leachability. The leachability studies were conducted using the Toxicity Characteristic Leaching Procedure. The blocks were analyzed for various physical and leachable chemical parameters at the end of each curing period. Based on the results of the analysis, two recipe mixtures, with compositions - 50% of [waste + (120 g Ca(OCl)(2) + 290 g Na(2)SO(4)) kg(-1) of waste] + 50% of binders, were validated for in situ stabilization into a secured landfill of CHWTSDF. 2010 Elsevier Ltd. All rights reserved.

  13. Characterization of Transport and Solidification in the Metal Recycling Processes

    Energy Technology Data Exchange (ETDEWEB)

    M. A. Ebadian; R. C. Xin; Z. F. Dong

    1997-08-06

    The characterization of the transport and solidification of metal in the melting and casting processes is significant for the optimization of the radioactively contaminated metal recycling and refining processes. . In this research project, the transport process in the melting and solidification of metal was numerically predicted, and the microstructure and radionuclide distribution have been characterized by scanning electron microscope/electron diffractive X-ray (SEWEDX) analysis using cesium chloride (CSC1) as the radionuclide surrogate. In the melting and solidification process, a resistance furnace whose heating and cooling rates are program- controlled in the helium atmosphere was used. The characterization procedures included weighing, melting and solidification, weighing after solidification, sample preparation, and SEM/EDX analysis. This analytical methodology can be used to characterize metal recycling and refining products in order to evaluate the performance of the recycling process. The data obtained provide much valuable information that is necessary for the enhancement of radioactive contaminated metal decontamination and recycling technologies. The numerical method for the prediction of the melting and solidification process can be implemented in the control and monitoring system-of the melting and casting process in radioactive contaminated metal recycling. The use of radionuclide surrogates instead of real radionuclides enables the research to be performed without causing harmfid effects on people or the community. This characterization process has been conducted at the Hemispheric Center for Environmental Technology (HCET) at Florida International University since October 1995. Tests have been conducted on aluminum (Al) and copper (Cu) using cesium chloride (CSCI) as a radionuclide surrogate, and information regarding the radionuclide transfer and distribution in melting and solidification process has been obtained. The numerical simulation of

  14. Hanford immobilized low-activity tank waste performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Mann, F.M.

    1998-03-26

    The Hanford Immobilized Low-Activity Tank Waste Performance Assessment examines the long-term environmental and human health effects associated with the planned disposal of the vitrified low-level fraction of waste presently contained in Hanford Site tanks. The tank waste is the by-product of separating special nuclear materials from irradiated nuclear fuels over the past 50 years. This waste has been stored in underground single and double-shell tanks. The tank waste is to be retrieved, separated into low and high-activity fractions, and then immobilized by private vendors. The US Department of Energy (DOE) will receive the vitrified waste from private vendors and plans to dispose of the low-activity fraction in the Hanford Site 200 East Area. The high-level fraction will be stored at Hanford until a national repository is approved. This report provides the site-specific long-term environmental information needed by the DOE to issue a Disposal Authorization Statement that would allow the modification of the four existing concrete disposal vaults to provide better access for emplacement of the immobilized low-activity waste (ILAW) containers; filling of the modified vaults with the approximately 5,000 ILAW containers and filler material with the intent to dispose of the containers; construction of the first set of next-generation disposal facilities. The performance assessment activity will continue beyond this assessment. The activity will collect additional data on the geotechnical features of the disposal sites, the disposal facility design and construction, and the long-term performance of the waste. Better estimates of long-term performance will be produced and reviewed on a regular basis. Performance assessments supporting closure of filled facilities will be issued seeking approval of those actions necessary to conclude active disposal facility operations. This report also analyzes the long-term performance of the currently planned disposal system as a basis

  15. Rapid extraction and determination of amphetamines in human urine samples using dispersive liquid-liquid microextraction and solidification of floating organic drop followed by high performance liquid chromatography.

    Science.gov (United States)

    Ahmadi-Jouibari, Toraj; Fattahi, Nazir; Shamsipur, Mojtaba

    2014-06-01

    A novel, rapid, simple and sensitive dispersive liquid-liquid microextraction method based on the solidification of floating organic drop (DLLME-SFO) combined with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) was used to determine amphetamine and methamphetamine in urine samples. The factors affecting the extraction efficiency of DLLME-SFO such as the kind and volume of the extraction and the disperser solvents, effect of concentration of K2CO3 and extraction time were investigated and the optimal extraction conditions were established. Under the optimum conditions (extraction solvent: 30.0μl 1-undecanol; disperser solvent: 300μl acetonitrile; buffer concentration: 2% (w/v) K2CO3 and extraction time: 1min), calibration curves are linear in the range of 10-3000μgl(-1) and limit of detections (LODs) are in the range of 2-8μgl(-1). The relative standard deviations (RSDs) for 100μgl(-1) of amphetamine and methamphetamine in diluted urine are in the range of 6.2-7.8% (n=7). The method was successfully applied for the determination of amphetamine and methamphetamine in the actual urine samples. The relative recoveries of urine samples spiked with amphetamine and methamphetamine are 87.8-113.2%. The obtained results show that DLLME-SFO combined with HPLC-UV is a fast and simple method for the determination of amphetamine and methamphetamine in urine. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Regulatory basis for the Waste Isolation Pilot Plant performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    HOWARD,BRYAN A.; CRAWFORD,M.B.; GALSON,D.A.; MARIETTA,MELVIN G.

    2000-05-22

    The Waste Isolation Pilot Plant (WIPP) is the first operational repository designed for the safe disposal of transuranic (TRU) radioactive waste from the defense programs of the US Department of Energy (DOE). The US Environmental Protection Agency (EPA) is responsible for certifications and regulation of the WIPP facility for the radioactive components of the waste. The EPA has promulgated general radioactive waste disposal standards at 40 CFR Part 191. and WIPP-specific criteria to implement and interpret the generic disposal standards at 40 CFR Part 194. In October 1996. the DOE submitted its Compliance Certification Application (CCA) to the EPA to demonstrate compliance with the disposal standards at Subparts B and C of 40 CFR Part 191. This paper summarizes the development of the overall legal framework for radioactive waste disposal at the WIPP, the parallel development of the WIPP performance assessment (PA), and how the EPA disposal standards and implementing criteria formed the basis for the CCA WIPP PA. The CCA resulted in a certification in May 1998 by the EPA of the WIPP'S compliance with the EPA's disposal standard, thus enabling the WIPP to begin radioactive waste disposal.

  17. Solidification of metal oxide from electrokinetic-electrodialytic decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Daeseo; Park, Uk-Ryang; Kim, Gye-Nam; Kim, Seung-Soo; Moon, Jei-Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Electrokinectic-electrodialytic decontamination technology reduced 80% of the concentration of the uranium soil waste to below the concentration of self-disposal. After conducting electrokinectic-electrodialytic decontamination, more than 10% of the remainder of radioactive waste from the cathodes of electrokinectic-electrodialytic equipment were produced. To dispose of such waste, it is necessary to solidify second radioactive waste owing to the requirements of radioactive waste from public corporations. In this study, a solidification experiment was carried out using a polymer. At first, a sampling of second radioactive waste was conducted. Then, second radioactive waste and a polymer were mixed. Third, the solidified state between the second radioactive waste and polymer was checked. In our next study, an experiment for the requirements of a public radioactive waste corporation will be conducted.

  18. Radioactive Waste Management Complex low-level waste radiological performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Maheras, S.J.; Rood, A.S.; Magnuson, S.O.; Sussman, M.E.; Bhatt, R.N.

    1994-04-01

    This report documents the projected radiological dose impacts associated with the disposal of radioactive low-level waste at the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory. This radiological performance assessment was conducted to evaluate compliance with applicable radiological criteria of the US Department of Energy and the US Environmental Protection Agency for protection of the public and the environment. The calculations involved modeling the transport of radionuclides from buried waste, to surface soil and subsurface media, and eventually to members of the public via air, groundwater, and food chain pathways. Projections of doses were made for both offsite receptors and individuals inadvertently intruding onto the site after closure. In addition, uncertainty and sensitivity analyses were performed. The results of the analyses indicate compliance with established radiological criteria and provide reasonable assurance that public health and safety will be protected.

  19. Solid waste digestors: process performance and practice for municipal solid waste digestion.

    Science.gov (United States)

    Lissens, G; Vandevivere, P; De Baere, L; Biey, E M; Verstrae, W

    2001-01-01

    The most common types of anaerobic digesters for solid wastes have been compared based on biological and technical performance and reliability. Batch systems have the most simple designs and are the least expensive solid waste digesters. They have high potential for application in developing countries. Two-stage systems are the most complex and most expensive systems. Their greatest advantage lies in the equalisation of the organic loading rate in the first stage, allowing a more constant feeding rate of the methanogenic second stage. Two-stage systems with biomass accumulation devices in the second stage display a larger resistance toward toxicants and inhibiting substances such as ammonia. However, the large majority of industrial applications use one-stage systems and these are evenly split between "dry" systems (wastes are digested as received) and "wet" systems (wastes are slurried to about 12% total solids). Regarding biological performance, this study compares the different digester systems in terms of organic loading rates and biogas yields considering differences in input waste composition. As a whole, "dry" designs have proven reliable due to their higher biomass concentration, controlled feeding and spatial niches. Moreover, from a technical viewpoint the "dry" systems are more robust and flexible than "wet' systems.

  20. Effect of yoghurt waste on gut morphology and growth performance ...

    African Journals Online (AJOL)

    The experiment was carried out to determine the effect of yoghurt waste on intestinal morphology and growth performance of pigs weaned at 7 weeks of age. A total of 20 weaned pigs (15.6 ± 2kg, initial body weight {BW}) were randomly assigned in groups of four, to 5 experimental treatments in a randomized block design.

  1. Estimation of waste package performance requirements for a nuclear waste repository in basalt

    Energy Technology Data Exchange (ETDEWEB)

    Wood, B J

    1980-07-01

    A method of developing waste package performance requirements for specific nuclides is described, and based on federal regulations concerning permissible concentrations in solution at the point of discharge to the accessible environment, a simple and conservative transport model, and baseline and potential worst-case release scenarios.

  2. Challenges when performing economic optimization of waste treatment: A review

    DEFF Research Database (Denmark)

    Juul, Nina; Münster, Marie; Ravn, H.

    2013-01-01

    example, but models focusing on energy production have also been developed, as well as models which take into account a plant’s economies of scale, environmental impact, material recovery and social costs. Finally, models combining different criteria for the selection of waste treatment methods in multi......-criteria analysis have been developed.A thorough updated review of the existing models is presented, and the main challenges and crucial parameters that need to be taken into account when assessing the economic performance of waste treatment alternatives are identified. The review article will assist both policy...

  3. Langevin formalism for solidification

    Energy Technology Data Exchange (ETDEWEB)

    Karma, A. (Department of Physics, Northeastern University, Boston, Massachusetts 02115 (United States))

    1993-05-31

    The question of how thermal noise should be incorporated in the continuum equations of solidification in a way which is consistent with both bulk and interfacial equilibrium fluctuations is investigated. The proper Langevin formalism which accomplishes this task is found to consist of the usual bulk forces, which remain unaffected by the presence of a two-phase boundary, and an extra stochastic force on the interface associated with its kinetics. The relevance of this force in the context of pattern formation is examined.

  4. Solute redistribution in dendritic solidification with diffusion in the solid

    Science.gov (United States)

    Ganesan, S.; Poirier, D. R.

    1989-01-01

    An investigation of solute redistribution during dendritic solidification with diffusion in the solid has been performed using numerical techniques. The extent of diffusion is characterized by the instantaneous and average diffusion parameters. These parameters are functions of the diffusion Fourier number, the partition ratio and the fraction solid. Numerical results are presented as an approximate model, which is used to predict the average diffusion parameter and calculate the composition of the interdendritic liquid during solidification.

  5. Fluctuations in solidification

    Energy Technology Data Exchange (ETDEWEB)

    Karma, A. (Physics Department, Northeastern University, Boston, Massachusetts 02115 (United States))

    1993-11-01

    We present an analytical treatment of (i) the incorporation of thermal noise in the basic continuum models of solidification, (ii) fluctuations about nonequilibrium steady states, and (iii) the amplification of noise near the onset of morphological instability. In (i), we find that the proper Langevin formalism, consistent with both bulk and interfacial equilibrium fluctuations, consists of the usual bulk forces and an extra stochastic force on the interface associated with its local kinetics. At sufficiently large solidification rate, this force affects interfacial fluctuations on scales where they are macroscopically amplified and, thus, becomes relevant. An estimate of this rate is given. In (ii), we extend the Langevin formalism outside of equilibrium to characterize the fluctuations of a stationary and a directionally solidified planar interface in a temperature gradient. Finally, in (iii), we derive an analytic expression for the linear growth of the mean-square amplitude of fluctuations slightly above the onset of morphological instability. The amplitude of the noise is found to be determined by the small parameter [ital k][sub [ital B]T[ital E]d0][sup [ital c]l][sub [ital T

  6. Microstructural development during solidification of stainless steel alloys

    Science.gov (United States)

    Elmer, J. W.; Allen, S. M.; Eagar, T. W.

    1989-10-01

    The microstructures that develop during the solidification of stainless steel alloys are related to the solidification conditions and the specific alloy composition. The solidification conditions are determined by the processing method, i.e., casting, welding, or rapid solidification, and by parametric variations within each of these techniques. One variable that has been used to characterize the effects of different processing conditions is the cooling rate. This factor and the chemical composition of the alloy both influence (1) the primary mode of solidification, (2) solute redistribution and second-phase formation during solidification, and (3) the nucleation and growth behavior of the ferrite-to-austenite phase transformation during cooling. Consequently, the residual ferrite content and the microstructural morphology depend on the cooling rate and are governed by the solidification process. This paper investigates the influence of cooling rate on the microstructure of stainless steel alloys and describes the conditions that lead to the many microstructural morphologies that develop during solidification. Experiments were performed on a series of seven high-purity Fe-Ni-Cr alloys that spanned the line of twofold saturation along the 59 wt pct Fe isopleth of the ternary alloy system. High-speed electron-beam surface-glazing was used to melt and resolidify these alloys at scan speeds up to 5 m/s. The resulting cooling rates were shown to vary from 7°C/s to 7.5×106°C/s, and the resolidified melts were analyzed by optical metallographic methods. Five primary modes of solidification and 12 microstructural morphologies were characterized in the resolidified alloys, and these features appear to be a complete “set” of the possible microstructures for 300-series stainless steel alloys. The results of this study were used to create electron-beam scan speed vs composition diagrams, which can be used to predict the primary mode of solidification and the

  7. Performance assessment requirements for the identification and tracking of transuranic waste intended for disposal at the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Snider, C.A. [Department of Energy, Carlsbad, NM (United States); Weston, W.W. [Westinghouse Electric Corp., Carlsbad, NM (United States)

    1997-11-01

    To demonstrate compliance with environmental radiation protection standards for management and disposal of transuranic (TRU) radioactive wastes, a performance assessment (PA) of the Waste Isolation Pilot Plant (WIPP) was made of waste-waste and waste-repository interactions and impacts on disposal system performance. An estimate of waste components and accumulated quantities was derived from a roll-up of the generator/storage sites` TRU waste inventories. Waste components of significance, and some of negligible effect, were fixed input parameters in the model. The results identified several waste components that require identification and tracking of quantities to ensure that repository limits are not exceeded. The rationale used to establish waste component limits based on input estimates is discussed. The distinction between repository limits and waste container limits is explained. Controls used to ensure that no limits are exceeded are identified. For waste components with no explicit repository based limits, other applicable limits are contained in the WIPP Waste Acceptance Criteria (WAC). The 10 radionuclides targeted for identification and tracking on either a waste container or a waste stream basis include Am-241, Pu-238, Pu-239, Pu-240, Pu-242, U-233, U-234, U-238, Sr-90, and Cs-137. The accumulative activities of these radionuclides are to be inventoried at the time of emplacement in the WIPP. Changes in inventory curie content as a function of radionuclide decay and ingrowth over time will be calculated and tracked. Due to the large margin of compliance demonstrated by PA with the 10,000 year release limits specified, the quality assurance objective for radioassay of the 10 radionuclides need to be no more restrictive than those already identified for addressing the requirements imposed by transportation and WIPP disposal operations in Section 9 of the TRU Waste Characterization Quality Assurance Program Plan. 6 refs.

  8. Dendritic Alloy Solidification Experiment (DASE)

    Science.gov (United States)

    Beckermann, C.; Karma, A.; Steinbach, I.; deGroh, H. C., III

    2001-01-01

    A space experiment, and supporting ground-based research, is proposed to study the microstructural evolution in free dendritic growth from a supercooled melt of the transparent model alloy succinonitrile-acetone (SCN-ACE). The research is relevant to equiaxed solidification of metal alloy castings. The microgravity experiment will establish a benchmark for testing of equiaxed dendritic growth theories, scaling laws, and models in the presence of purely diffusive, coupled heat and solute transport, without the complicating influences of melt convection. The specific objectives are to: determine the selection of the dendrite tip operating state, i.e. the growth velocity and tip radius, for free dendritic growth of succinonitrile-acetone alloys; determine the growth morphology and sidebranching behavior for freely grown alloy dendrites; determine the effects of the thermal/solutal interactions in the growth of an assemblage of equiaxed alloy crystals; determine the effects of melt convection on the free growth of alloy dendrites; measure the surface tension anisotropy strength of succinon itrile -acetone alloys establish a theoretical and modeling framework for the experiments. Microgravity experiments on equiaxed dendritic growth of alloy dendrites have not been performed in the past. The proposed experiment builds on the Isothermal Dendritic Growth Experiment (IDGE) of Glicksman and coworkers, which focused on the steady growth of a single crystal from pure supercooled melts (succinonitrile and pivalic acid). It also extends the Equiaxed Dendritic Solidification Experiment (EDSE) of the present investigators, which is concerned with the interactions and transients arising in the growth of an assemblage of equiaxed crystals (succinonitrile). However, these experiments with pure substances are not able to address the issues related to coupled heat and solute transport in growth of alloy dendrites.

  9. Segregation behaviour and phase developments during solidification of Inconel 625; effect of iron and carbon

    DEFF Research Database (Denmark)

    Højerslev, Christian; Tiedje, Niels; Hald, John

    2004-01-01

    of the protective layer is observed to occur predominately along either the dendrite cores, D.C. or in the inter-dendric regions, I.D. ¡V which occasionally results in unexpected large (and possibly detrimental) local corrosion rates. In this investigation microstructure characterization was performed......The key to improve the performance of Inconel 625 weld overlays applied for corrosion resistance in waste incinerator plants is to understand the solidification process: At present, enhanced resistance against fireside corrosion in waste incinerator boilers is commonly achieved by overlay welding...... with nickel based alloys i.e. Inconel grades. The final layer has a thickness of at least 2 mm. This layer has a dendritic morphology with a dendrite arm spacing of a few microns. In general, this combination of material and process technology provides an adequate solution. However, corrosive attacks...

  10. Performance of municipal waste stabilization ponds in the Canadian Arctic

    DEFF Research Database (Denmark)

    Ragush, Colin M.; Schmidt, Jordan J.; Krkosek, Wendy H.

    2015-01-01

    The majority of small remote communities in the Canadian arctic territory of Nunavut utilize waste stabilization ponds (WSPs) for municipal wastewater treatment because of their relatively low capital and operational costs, and minimal complexity. New national effluent quality regulations have been...... implemented in Canada, but not yet applied to Canada’s Arctic due to uncertainty related to the performance of current wastewater treatment systems. Waste stabilization pond (WSP) treatment performance is impacted by community water use, pond design, and climate. The greatest challenge arctic communities......), and ammonia-nitrogen were measured during the summer treatment period (late June until early September) from 2011 to 2014 in the WSP systems of four Nunavut communities; Pond Inlet, Clyde River, Grise Fiord and Kugaaruk. Monitoring results showed that WSPs in their current single cell design can achieve...

  11. Performance and Reliability of Exhaust Gas Waste Heat Recovery Units

    Science.gov (United States)

    2014-09-01

    Khalil, Zohir, and Farid (2010) investigated heat transfer related to swirling and non- swirling flows through sudden pipe expansions at constant pumping... swirl in air flow in a tube for a concentric double- pipe heat exchanger. The use of a snail entrance feature increased the Nusselt number in the...exhaust gas WHRU. 14. SUBJECT TERMS waste heat recovery, heat recovery performance, swirling flow , pressure drop penalty, temperature

  12. Using a visual plate waste study to monitor menu performance.

    Science.gov (United States)

    Connors, Priscilla L; Rozell, Sarah B

    2004-01-01

    Two visual plate waste studies were conducted in 1-week phases over a 1-year period in an acute care hospital. A total of 383 trays were evaluated in the first phase and 467 in the second. Food items were ranked for consumption from a low (1) to high (6) score, with a score of 4.0 set as the benchmark denoting a minimum level of acceptable consumption. In the first phase two entrees, four starches, all of the vegetables, sliced white bread, and skim milk scored below the benchmark. As a result six menu items were replaced and one was modified. In the second phase all entrees scored at or above 4.0, as did seven vegetables, and a dinner roll that replaced sliced white bread. Skim milk continued to score below the benchmark. A visual plate waste study assists in benchmarking performance, planning menu changes, and assessing effectiveness.

  13. Performance assessment for municipal solid waste collection in Taiwan.

    Science.gov (United States)

    Huang, You-Ti; Pan, Tze-Chin; Kao, Jehng-Jung

    2011-04-01

    Collecting municipal solid waste (MSW) is a major and expensive task for local waste management authorities, thus efficient MSW collection is a necessity. This study presents a procedure for developing an aggregate indicator (AI) to assess MSW collection efficiency based on multiple factors. The applicabilities of various key performance indicators (KPIs) are evaluated based on five selection criteria, and five KPIs are chosen to form the AI. The relative efficiencies of local MSW collection services are analyzed by the data envelopment analysis (DEA) method. A set of common weights for all five KPIs is then generated based on DEA results and four selection rules by modifying a previous approach. Finally, the proposed AI is applied to assess the MSW collection services provided by 307 local governments in Taiwan, and associated results are compared and discussed. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Microstructure and Corrosion Resistance Property of a Zn-AI-Mg Alloy with Different Solidification Processes

    Directory of Open Access Journals (Sweden)

    Jiang Guang-rui

    2017-01-01

    Full Text Available Zn-Al-Mg alloy coating attracted much attention due to its high corrosion resistance properties, especially high anti-corrosion performance at the cut edge. As the Zn-Al-Mg alloy coating was usually produced by hot-dip galvanizing method, solidification process was considered to influence its microstructure and corrosion properties. In this work, a Zn-Al-Mg cast alloy was melted and cooled to room temperature with different solidification processes, including water quench, air cooling and furnace cooling. Microstructure of the alloy with different solidification processes was characterized by scanning electron microscopy (SEM. Result shows that the microstructure of the Zn-Al-Mg alloy are strongly influenced by solidification process. With increasing solidification rate, more Al is remained in the primary crystal. Electrochemical analysis indicates that with lowering solidification rate, the corrosion current density of the Zn-Al-Mg alloy decreases, which means higher corrosion resistance.

  15. Performance of continuous biodigestors supplied by young bull waste

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Monica Sarolli S. de M. [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil)], E-mail: monicas@unioeste.br; Lucas Junior, Jorge de [Universidade Estadual Paulista (FCA/UNESP), Jaboticabal, SP (Brazil). Fac. de Ciencias Agrarias e Veterinarias; Pivetta, Laercio Augusto [Universidade Estadual do Oeste do Parana (UNIOESTE), Marechal C. Rondon, PR (Brazil); Costa, Luiz A. de Mendonca

    2008-07-01

    The various systems of livestock farming in the industrial model promote physical and chemical changes on waste. In the fattening of cattle in the model of confinement for young bulls has been a reversal in the proportion between roughage and concentrate, or the animals receive a higher amount of protein compared to the traditional system of confinement. This change of the waste characteristics involves modification in the system of treatment used. In this work, it was aimed to evaluate the performance of batch biodigestors operated in continuous system, supplied by young bulls waste which received two differentiated diets by the proportion between roughage and concentrate, whether or not containing inoculum in the substrate composition and subjected to three levels of temperature (25, 35 and 40 deg C). The parameters evaluated were: reduction of total solids (TS) and volatile (VS), and the potential for biogas production. The results showed a reduction of TS higher in the treatment which was not used inoculum for diet 1 and 2 with the exception of the treatment which the substrate was referred to temperature of 40 deg C on diet 2. For the reduction of VS there was no interference from the use of inoculum on diet 1. On diet 2, the largest reductions were observed without the use of inoculum, with the exception of the 40 deg C temperature. For the potential for biogas production the treatment where they used waste derived from animals fed with diet 2, with the use of inoculum, in the temperature of 40 deg C showed the greatest value, or 0.53 m{sup 3} of biogas per kg TS added. (author)

  16. Secondary Waste Simulant Development for Cast Stone Formulation Testing

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Renee L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rinehart, Donald E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Swanberg, David J. [Washington River Protection Solutions, Richland, WA (United States); Mahoney, J. [Washington River Protection Solutions, Richland, WA (United States)

    2015-04-01

    Washington River Protection Solutions, LLC (WRPS) funded Pacific Northwest National Laboratory (PNNL) to conduct a waste form testing program to implement aspects of the Secondary Liquid Waste Treatment Cast Stone Technology Development Plan (Ashley 2012) and the Hanford Site Secondary Waste Roadmap (PNNL 2009) related to the development and qualification of Cast Stone as a potential waste form for the solidification of aqueous wastes from the Hanford Site after the aqueous wastes are treated at the Effluent Treatment Facility (ETF). The current baseline is that the resultant Cast Stone (or grout) solid waste forms would be disposed at the Integrated Disposal Facility (IDF). Data and results of this testing program will be used in the upcoming performance assessment of the IDF and in the design and operation of a solidification treatment unit planned to be added to the ETF. The purpose of the work described in this report is to 1) develop simulants for the waste streams that are currently being fed and future WTP secondary waste streams also to be fed into the ETF and 2) prepare simulants to use for preparation of grout or Cast Stone solid waste forms for testing.

  17. Performance Analysis of Waste Heat Driven Pressurized Adsorption Chiller

    KAUST Repository

    LOH, Wai Soong

    2010-01-01

    This article presents the transient modeling and performance of waste heat driven pressurized adsorption chillers for refrigeration at subzero applications. This innovative adsorption chiller employs pitch-based activated carbon of type Maxsorb III (adsorbent) with refrigerant R134a as the adsorbent-adsorbate pair. It consists of an evaporator, a condenser and two adsorber/desorber beds, and it utilizes a low-grade heat source to power the batch-operated cycle. The ranges of heat source temperatures are between 55 to 90°C whilst the cooling water temperature needed to reject heat is at 30°C. A parametric analysis is presented in the study where the effects of inlet temperature, adsorption/desorption cycle time and switching time on the system performance are reported in terms of cooling capacity and coefficient of performance. © 2010 by JSME.

  18. Microwave waste processing technology overview

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, R.D.

    1993-02-01

    Applications using microwave energy in the chemical processing industry have increased within the last ten years. Recently, interest in waste treatment applications process development, especially solidification, has grown. Microwave waste processing offers many advantages over conventional waste treatment technologies. These advantages include a high density, leach resistant, robust waste form, volume and toxicity reduction, favorable economics, in-container treatment, good public acceptance, isolated equipment, and instantaneous energy control. The results from the {open_quotes}cold{close_quotes} demonstration scale testing at the Rocky Flats nuclear weapons facility are described. Preliminary results for a transuranic (TRU) precipitation sludge indicate that volume reductions of over 80% are achievable over the current immobilization process. An economic evaluation performed demonstrated cost savings of $11.68 per pound compared to the immobilization process currently in use on wet sludge.

  19. Hanford Site Secondary Waste Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Westsik, Joseph H.

    2009-01-29

    Summary The U.S. Department of Energy (DOE) is making plans to dispose of 54 million gallons of radioactive tank wastes at the Hanford Site near Richland, Washington. The high-level wastes and low-activity wastes will be vitrified and placed in permanent disposal sites. Processing of the tank wastes will generate secondary wastes, including routine solid wastes and liquid process effluents, and these need to be processed and disposed of also. The Department of Energy Office of Waste Processing sponsored a meeting to develop a roadmap to outline the steps necessary to design the secondary waste forms. Representatives from DOE, the U.S. Environmental Protection Agency, the Washington State Department of Ecology, the Oregon Department of Energy, Nuclear Regulatory Commission, technical experts from the DOE national laboratories, academia, and private consultants convened in Richland, Washington, during the week of July 21-23, 2008, to participate in a workshop to identify the risks and uncertainties associated with the treatment and disposal of the secondary wastes and to develop a roadmap for addressing those risks and uncertainties. This report describes the results of the roadmap meeting in Richland. Processing of the tank wastes will generate secondary wastes, including routine solid wastes and liquid process effluents. The secondary waste roadmap workshop focused on the waste streams that contained the largest fractions of the 129I and 99Tc that the Integrated Disposal Facility risk assessment analyses were showing to have the largest contribution to the estimated IDF disposal impacts to groundwater. Thus, the roadmapping effort was to focus on the scrubber/off-gas treatment liquids with 99Tc to be sent to the Effluent Treatment Facility for treatment and solidification and the silver mordenite and carbon beds with the captured 129I to be packaged and sent to the IDF. At the highest level, the secondary waste roadmap includes elements addressing regulatory and

  20. Solidification behaviour of Ni-base superalloy CMSX-6

    OpenAIRE

    Ma, D.; Meyer Ter Vehn, M.; Busse, P.; Sahm, P.

    1993-01-01

    The solidification behaviour of the single crystal superalloy CMSX-6 has been investigated using directional solidification technique. The longitudinal sections of the quenched samples were taken to identify the solidification structure. The experimentally determined solidification diagram gives the relationship between solidification structure and process parameters. The analysis of the transverse sections yields the solidification sequence and the solid fraction against the temperature decr...

  1. Performance validation of commercially available mobile waste-assay systems: Preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Schanfein, M.; Bonner, C.; Maez, R. [Los Alamos National Lab., NM (United States)] [and others

    1997-11-01

    Prior to disposal, nuclear waste must be accurately characterized to identify and quantify the radioactive content to reduce the radioactive hazard to the public. Validation of the waste-assay systems` performance is critical for establishing the credibility of the assay results for storage and disposal purposes. Canberra Nuclear has evaluated regulations worldwide and identified standard, modular, neutron- and gamma-waste-assay systems that can be used to characterize a large portion of existing and newly generated transuranic (TRU) and low-level waste. Before making claims of guaranteeing any system`s performance for specific waste types, the standardized systems` performance be evaluated. 7 figs., 11 tabs.

  2. Waste Form Release Data Package for the 2001 Immobilized Low-Activity Waste Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    McGrail, B. Peter; Icenhower, Jonathan P.; Martin, Paul F.; Schaef, Herbert T.; O' Hara, Matthew J.; Rodriguez, Eugenio; Steele, Jackie L.

    2001-02-01

    This data package documents the experimentally derived input data on the representative waste glasses LAWABP1 and HLP-31 that will be used for simulations of the immobilized lowactivity waste disposal system with the Subsurface Transport Over Reactive Multiphases (STORM) code. The STORM code will be used to provide the near-field radionuclide release source term for a performance assessment to be issued in March of 2001. Documented in this data package are data related to 1) kinetic rate law parameters for glass dissolution, 2) alkali-H ion exchange rate, 3) chemical reaction network of secondary phases that form in accelerated weathering tests, and 4) thermodynamic equilibrium constants assigned to these secondary phases. The kinetic rate law and Na+-H+ ion exchange rate were determined from single-pass flow-through experiments. Pressurized unsaturated flow and vapor hydration experiments were used for accelerated weathering or aging of the glasses. The majority of the thermodynamic data were extracted from the thermodynamic database package shipped with the geochemical code EQ3/6. However, several secondary reaction products identified from laboratory tests with prototypical LAW glasses were not included in this database, nor are the thermodynamic data available in the open literature. One of these phases, herschelite, was determined to have a potentially significant impact on the release calculations and so a solubility product was estimated using a polymer structure model developed for zeolites. Although this data package is relatively complete, final selection of ILAW glass compositions has not been done by the waste treatment plant contractor. Consequently, revisions to this data package to address new ILAW glass formulations are to be regularly expected.

  3. Melting and solidification characteristics of a mixture of two types of latent heat storage material in a vessel

    Science.gov (United States)

    Yu, JikSu; Horibe, Akihiko; Haruki, Naoto; Machida, Akito; Kato, Masashi

    2016-11-01

    In this study, we investigated the fundamental melting and solidification characteristics of mannitol, erythritol, and their mixture (70 % by mass mannitol: 30 % by mass erythritol) as potential phase-change materials (PCMs) for latent heat thermal energy storage systems, specifically those pertaining to industrial waste heat, having temperatures in the range of 100-250 °C. The melting point of erythritol and mannitol, the melting peak temperature of their mixture, and latent heat were measured using differential scanning calorimetry. The thermal performance of the mannitol mixture was determined during melting and solidification processes, using a heat storage vessel with a pipe heat exchanger. Our results indicated phase-change (fusion) temperatures of 160 °C for mannitol and 113 and 150 °C for the mannitol mixture. Nondimensional correlation equations of the average heat transfer during the solidification process, as well as the temperature and velocity efficiencies of flowing silicon oil in the pipe and the phase-change material (PCM), were derived using several nondimensional parameters.

  4. Nucleation and solidification of thin walled ductile iron - Experiments and numerical simulation

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2005-01-01

    Investigation of solidification of thin walled ductile cast iron has been performed based on experiments and numerical simulation. The experiments were based on temperature and microstructure examination. Results of the experiments have been compared with a 1-D numerical solidification model...

  5. Nonequilibrium solidification in undercooled Ti45Al55 melts

    Science.gov (United States)

    Hartmann, H.; Galenko, P. K.; Holland-Moritz, D.; Kolbe, M.; Herlach, D. M.; Shuleshova, O.

    2008-04-01

    Ti-Al alloys are of high technological interest as light-weight high-performance materials. When produced by solidification from the liquid state, the material properties of as-solidified materials are strongly dependent on the conditions governing the solidification process. Nonequilibrium solidification from the state of an undercooled liquid may result to the formation of metastable solid materials. On the one hand undercooling under special cases may influence the phase selection behavior during solidification, and on the other hand during rapid growth of solid phases in undercooled melts nonequilibrium effects such as solute trapping and disorder trapping may occur. In the present work containerless processing by electromagnetic levitation is used to undercool Ti45Al55 melts deeply below the liquidus temperature. The dendrite growth velocity during the solidification is measured as a function of undercooling by application of a high-speed video camera. In situ diffraction experiments at ESRF in Grenoble and microstructure investigations are performed in order to identify the primary solidified phases. The experimental findings are interpreted within current theoretical models for dendritic growth and solute trapping.

  6. Rapid Solidification of Magnetic Oxides

    Science.gov (United States)

    Kalonji, G.; Deguire, M. R.

    1985-01-01

    The enhanced control over microstructural evolution inherent in rapid solidification processing techniques are exploited to create novel ceramic magnetic materials. The great sensitivity of magnetic properties to local structure provides a powerful probe both for the study of structure and of microscopic solidification mechanisms. The first system studied is the SrO-Fe2O3 binary, which contains the commercially important hard magnetic compound strontium hexaferrite. The products were analyzed by transmission electron microscopy, Mossbauer spectroscopy, magnetic measurements, and differential thermal analysis. As-quenched ribbons contain high concentrations of super-paramagnetic particles, 80 to 250 Angstroms in diameter, in a glassy matrix. This suggests the possibility of crystallizing monodomain strontium hexaferrite during subsequent heat treatment, with a resulting increase in coercivity over conventionally processed ferrite magnets. That magnetic properties can be controlled in solidification processing by varying the quench rate is demonstrated.

  7. Preparation and Performance of Asphalt Compound Modified with Waste Crumb Rubber and Waste Polyethylene

    Directory of Open Access Journals (Sweden)

    Yuqiao Yang

    2016-01-01

    Full Text Available Three kinds of modified asphalt were prepared by adding waste crumb rubber (WCR, waste polyethylene (WPE, and WCR/WPE to base asphalt, respectively. The influence of different doses on the performance of modified asphalt, such as 25°C penetration, softening point, 5°C ductility, and 135°C, 165°C viscosity, was studied, and the modification mechanism of modified asphalt was discussed through the fluorescence microscope. As the waterproofing materials, the waterproofness of WCR/WPE compound modified asphalt was tested. The results show that the WPE modified asphalt has excellent resistance to high temperature and WCR modified asphalt has good low temperature resistance. The resistance to deformation ability of WPE modified asphalt is better than that of the WCR modified asphalt. The 135°C viscosity of compound modified asphalt is better than that of WPE and WCR modified asphalt. In addition, the waterproofness of compound modified asphalt using waterproofing materials is better than that of common waterproofing materials.

  8. Solidification/stabilization of fly ash from city refuse incinerator facility and heavy metal sludge with cement additives.

    Science.gov (United States)

    Cerbo, Atlas Adonis V; Ballesteros, Florencio; Chen, Teng Chien; Lu, Ming-Chun

    2017-01-01

    Solidification and stabilization are well-known technologies used for treating hazardous waste. These technologies that use cementitious binder have been applied for decades as a final treatment procedure prior to the hazardous waste disposal. In the present work, hazardous waste like fly ash containing high concentrations of heavy metals such Zn (4715.56 mg/kg), Pb (1300.56 mg/kg), and Cu (534.72 mg/kg) and amounts of Ag, Cd, Co, Cr, Mn, and Ni was sampled from a city refuse incinerator facility. This fly ash was utilized in the solidification/stabilization of heavy metal sludge since fly ash has cement-like characteristics. Cement additives such as sodium sulfate, sodium carbonate, and ethylenediaminetetraacetic acid (EDTA) was incorporated to the solidified matrix in order to determine its effect on the solidification/stabilization performance. The solidified matrix was cured for 7, 14, 21, and 28 days prior for its physical and chemical characterizations. The results show that the solidified matrix containing 40% fly ash and 60% cement with heavy metal sludge was the formulation that has the highest fly ash content with a satisfactory strength. The solidified matrix was also able to immobilize the heavy metals both found in the fly ash and sludge based on the toxicity characteristic leaching procedure (TCLP) test. It also shows that the incorporation of sodium carbonate into the solidified matrix not only further improved the compressive strength from 0.36 MPa (without Na2CO3) to 0.54 MPa (with Na2CO3) but also increased its leaching resistance.

  9. An Alternative to Performing Remote-Handled Transuranic Waste Container Headspace Gas Sampling and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Spangler, L. R.; Djordjevic, S. M.; Kehrman, R. F.; Most, W. A.

    2002-02-26

    The Waste Isolation Pilot Plant (WIPP) is operating under a Resource Conservation and Recovery Act (RCRA) Hazardous Waste Facility Permit (HWFP) for contact-handled (CH) transuranic (TRU) waste. The HWFP contains limitations on allowable emissions from waste disposed in the underground. This environmental performance standard imposed on the WIPP consists of limiting volatile organic compound (VOC) emissions from emplaced waste to ensure protection of human health and the environment. The standard is currently met by tracking individual waste container headspace gas concentrations, which are determined by headspace gas sampling and analysis of CH TRU waste containers. The WIPP is seeking a HWFP modification to allow the disposal of remote-handled (RH) TRU waste. Because RH TRU waste is limited to approximately 5% of the waste volume and is emplaced in the disposal room walls, it is possible to bound the potential RH TRU waste contribution to VOC emissions using conservative upper bounds. These conservative upper bounds were developed as an alternative to RH TRU waste canister headspace gas sampling and analysis. The methodology used to perform the calculations used to evaluate VOC emissions from emplaced RH TRU waste canisters applied the same equations as those used to evaluate VOC emissions in the original HWFP application.

  10. Radionuclide Incorporation and Long Term Performance of Apatite Waste Forms

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jianwei [Louisiana State Univ., Baton Rouge, LA (United States); Lian, Jie [Rensselaer Polytechnic Inst., Troy, NY (United States); Gao, Fei [Univ. of Michigan, Ann Arbor, MI (United States)

    2016-01-04

    This project aims to combines state-of-the-art experimental and characterization techniques with atomistic simulations based on density functional theory (DFT) and molecular dynamics (MD) simulations. With an initial focus on long-lived I-129 and other radionuclides such as Cs, Sr in apatite structure, specific research objectives include the atomic scale understanding of: (1) incorporation behavior of the radionuclides and their effects on the crystal chemistry and phase stability; (2) stability and microstructure evolution of designed waste forms under coupled temperature and radiation environments; (3) incorporation and migration energetics of radionuclides and release behaviors as probed by DFT and molecular dynamics (MD) simulations; and (4) chemical durability as measured in dissolution experiments for long term performance evaluation and model validation.

  11. Solidification of nitrate solutions with alkali-activated slag and slag–metakaolin cements

    Energy Technology Data Exchange (ETDEWEB)

    Rakhimova, Nailia R., E-mail: rahimova.07@list.ru [Kazan State University of Architecture and Engineering, Kazan (Russian Federation); Rakhimov, Ravil Z. [Kazan State University of Architecture and Engineering, Kazan (Russian Federation); Osin, Yury N. [Kazan Federal University, Kazan (Russian Federation); Naumkina, Natalia I.; Gubaidullina, Alfiya M. [Central Research Institute for Geology of Industrial Minerals, Kazan (Russian Federation); Yakovlev, Grigory I.; Shaybadullina, Arina V. [Kalashnikov Izhevsk State Technical University, Izhevsk (Russian Federation)

    2015-02-15

    Highlights: • The effectiveness of an AASC matrix for NaNO{sub 3} solution solidification is stated. • XRD, DTA-TG, and X-ray microtomography experiments were performed. • Crystallization of NaNO{sub 3} reduces the shrinkage of hardened AASC-based waste forms. • Metakaolin shortens the setting time and increases the compressive strength of AASC. - Abstract: The solidification of nitrate solutions with alkali-activated slag (AASC) and slag–metakaolin cements (AASMC) and the resulting setting times, compressive strengths, dimensional stability, water resistance, hydration products, microstructures, and macroporous network structures were evaluated. The influences of the alkali activator concentration, mineral composition of metakaolin, ratio of slag to slag + metakaolin, and concentration of NaNO{sub 3} on the cement performance were all evaluated in detail. The compressive strength of cemented nitrate solutions with AASC and AASMC aged for 28 days was from 13.4 to 42 MPa depending on the NaNO{sub 3} concentration. X-ray diffractometer, differential thermal analyzer, and electron microscope analyses suggested that NaNO{sub 3} crystallizes in cementitious matrices without reacting with the hydration products of AASC and AASMC. X-ray microtomography showed that the solidified NaNO{sub 3} solution with a salt concentration of 700 g/l and AASC had a denser microstructure without shrinkage microcracks, a smaller macropore volume, and smaller macropore sizes than hardened AASC-based paste mixed with water.

  12. Linear Stability of Binary Alloy Solidification for Unsteady Growth Rates

    Science.gov (United States)

    Mazuruk, K.; Volz, M. P.

    2010-01-01

    An extension of the Mullins and Sekerka (MS) linear stability analysis to the unsteady growth rate case is considered for dilute binary alloys. In particular, the stability of the planar interface during the initial solidification transient is studied in detail numerically. The rapid solidification case, when the system is traversing through the unstable region defined by the MS criterion, has also been treated. It has been observed that the onset of instability is quite accurately defined by the "quasi-stationary MS criterion", when the growth rate and other process parameters are taken as constants at a particular time of the growth process. A singular behavior of the governing equations for the perturbed quantities at the constitutional supercooling demarcation line has been observed. However, when the solidification process, during its transient, crosses this demarcation line, a planar interface is stable according to the linear analysis performed.

  13. Determination of performance criteria for high-level solidified nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Heckman, R.A.; Holdsworth, T.

    1979-05-07

    To minimize radiological risk from the operation of a waste management system, performance limits on volatilization, particulate dispersion, and dissolution characteristics of solidified high level waste must be specified. The results show clearly that the pre-emplacement environs are more limiting in establishing the waste form performance criteria than the post-emplacement environs. Absolute values of expected risk are very sensitive to modeling assumptions. The transportation and interim storage operations appear to be most limiting in determining the performance characteristics required. The expected values of risk do not rely upon the repositories remaining intact over the potentially hazardous lifetime of the waste.

  14. Modelling of solidification processing and continuous strip casting for copper-base alloys

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoudi, Jafar [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Materials Processing

    2000-04-01

    An experimental and numerical study was carried out to investigate the solidification process in a copper continuous strip casting process. Heat flow and solidification process has been experimentally studied. Cooling curves during solidification were registered using a thermocouple of type K connected to a data acquisition system. Temperature measurements in the mould and cooling water were also performed. The numerical model considers a generalized set of mass, momentum and heat equations that is valid for the solid, liquid and solidification interval in the cast. A k-{epsilon} turbulence model, produced with the commercial program CFX, is used to analyse the solidification process of pure copper in the mould region of the caster. The fluid flow, temperature and heat flux distributions in the mould region of the caster were computed. The shape and location of the solidification front were also determined. The effects of the parameters such as heat transfer coefficient, casting speed, casting temperature, heat of fusion and specific heat on the shape and location of the solidification front and the heat transport at the mould-cast interface were investigated. The predicted temperature and heat flux distributions were compared with experimental measurements, and reasonable agreement was obtained. The solidification behaviour of pure copper and different copper base alloys has been studied. A series of solidification experiments using DTA furnace, mirror furnace and levitation technique were performed on different copper-base alloys. The undercooling, cooling rates of the liquid and the solid states, solidification times and temperatures were evaluated from the curves. The cooling curves for different samples were simulated using a FEM solidification program. It was found that the calculated values of the heat of fusion were much lower than the tabulated ones. The fraction of solid formed before quenching, in the DTA experiments, has been observed to be much higher

  15. 20 Development and Performance Evaluation of a Low Cost Waste ...

    African Journals Online (AJOL)

    Choice-Academy

    Keywords: Waste-water; Toxicity; Micro-organisms; Filtration tank; Low-cost; Colony forming Unit (CFU). Introduction very community produces both liquid and solid wastes. The liquid portion, which is wastewater, is essentially the water supply to the community after it has been fouled by a variety of uses. Looking at.

  16. Reproductive performance of rabbits fed maize-milling waste based ...

    African Journals Online (AJOL)

    Owner

    treatments comprised of autoclaved and unautoclaved maize-milling waste, groundnut cake/maize meal diets formulated with 0 (I), ... waste was observed to improve the nutritional value of the diets and neither abortion nor still births were seen for the .... Autoclaving is the process of steam heating of feedstuffs to improve ...

  17. The Constitution, waste facility performance standards, and radioactive waste classification: Is equal protection possible?

    Energy Technology Data Exchange (ETDEWEB)

    Eye, R.V. [Kansas Dept. of Health and Environment, Topeka, KS (United States)

    1993-03-01

    The process for disposal of so-called low-level radioactive waste is deadlocked at present. Supporters of the proposed near-surface facilities assert that their designs will meet minimum legal and regulatory standards currently in effect. Among opponents there is an overarching concern that the proposed waste management facilities will not isolate radiation from the biosphere for an adequate length of time. This clash between legal acceptability and a perceived need to protect the environment and public health by requiring more than the law demand sis one of the underlying reasons why the process is deadlocked. Perhaps the most exhaustive public hearing yet conducted on low-level radioactive waste management has recently concluded in Illinois. The Illinois Low-Level Radioactive Waste Disposal Facility Sitting Commission conducted 71 days of fact-finding hearings on the safety and suitability of a site near Martinsville, Illinois, to serve as a location for disposition of low-level radioactive waste. Ultimately, the siting commission rejected the proposed facility site for several reasons. However, almost all the reasons were related, to the prospect that, as currently conceived, the concrete barrier/shallow-land burial method will not isolate radioactive waste from the biosphere. This paper reviews the relevant legal framework of the radioactive waste classification system and will argue that it is inadequate for long-lived radionuclides. Next, the paper will present a case for altering the classification system based on high-level waste regulatory considerations.

  18. A system dynamics-based environmental performance simulation of construction waste reduction management in China.

    Science.gov (United States)

    Ding, Zhikun; Yi, Guizhen; Tam, Vivian W Y; Huang, Tengyue

    2016-05-01

    A huge amount of construction waste has been generated from increasingly higher number of construction activities than in the past, which has significant negative impacts on the environment if they are not properly managed. Therefore, effective construction waste management is of primary importance for future sustainable development. Based on the theory of planned behaviors, this paper develops a system dynamic model of construction waste reduction management at the construction phase to simulate the environmental benefits of construction waste reduction management. The application of the proposed model is shown using a case study in Shenzhen, China. Vensim is applied to simulate and analyze the model. The simulation results indicate that source reduction is an effective waste reduction measure which can reduce 27.05% of the total waste generation. Sorting behaviors are a premise for improving the construction waste recycling and reuse rates which account for 15.49% of the total waste generated. The environmental benefits of source reduction outweigh those of sorting behaviors. Therefore, to achieve better environmental performance of the construction waste reduction management, attention should be paid to source reduction such as low waste technologies and on-site management performance. In the meantime, sorting behaviors encouragement such as improving stakeholders' waste awareness, refining regulations, strengthening government supervision and controlling illegal dumping should be emphasized. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Phosphate-bonded ceramics as candidate final-waste-form materials

    Energy Technology Data Exchange (ETDEWEB)

    Singh, D.; Wagh, A.S.; Cunnane, J.; Sutaria, M.; Kurokawa, S. [Argonne National Lab., IL (United States); Mayberry, J. [Science Applications International Corp., Idaho Falls, ID (United States)

    1994-12-31

    Room-temperature-setting phosphate-bonded ceramics were studied as candidate materials for stabilizing DOE low-level problem mixed wastes, which cannot be treated by other established stabilization techniques. Phosphates of Mg, Mg-Na, Al, and Zr were studied to stabilize ash-surrogate waste that contained RCRA metals as nitrates and RCRA organics. We show that for a typical loading of 35 wt.% of ash waste, the phosphate ceramics pass the Toxic Chemicals Leaching Procedure test (TCLP). The waste forms have high compression strength that exceeds ASTM recommendations for final waste forms. Detailed X-ray diffraction studies and differential thermal analyses of the waste forms show evidence of chemical reaction of the waste with phosphoric acid and the host matrix. SEM studies show evidence of physical bonding. Excellent performance in the leaching test is attributed to chemical solidification and to both physical and chemical bonding of the ash wastes with the phosphate ceramics.

  20. Proposed Model For Industrial Waste Management Practices and Its Impact on Organisational Performance

    Directory of Open Access Journals (Sweden)

    Suzy Noviyanti

    2015-03-01

    Full Text Available Due to environment protection issue, waste management becomes one of important factors in maintaining organization sustainability. In developed country, a growing number of companies began to integrate the pro environment practices, such as waste management practices, into their business strategy. In contrast, the implementation of waste management practices by business organizations in developing country, like Indonesia, is still rare. Waste generated by industries is greater than the capacity to manage this volume of waste. This poses a problem that leads to improper disposal of waste and pollution. This study aims to design a research model which investigates the relation of institutional environment including cognitive, regulatory, and normative element; manager environmental attitudes, worker environmental attitudes, environmental policy, strategic waste management practices, and financial performance.

  1. Los Alamos low-level waste performance assessment status

    Energy Technology Data Exchange (ETDEWEB)

    Wenzel, W.J.; Purtymun, W.D.; Dewart, J.M.; Rodgers, J.E. (comps.)

    1986-06-01

    This report reviews the documented Los Alamos studies done to assess the containment of buried hazardous wastes. Five sections logically present the environmental studies, operational source terms, transport pathways, environmental dosimetry, and computer model development and use. This review gives a general picture of the Los Alamos solid waste disposal and liquid effluent sites and is intended for technical readers with waste management and environmental science backgrounds but without a detailed familiarization with Los Alamos. The review begins with a wide perspective on environmental studies at Los Alamos. Hydrology, geology, and meteorology are described for the site and region. The ongoing Laboratory-wide environmental surveillance and waste management environmental studies are presented. The next section describes the waste disposal sites and summarizes the current source terms for these sites. Hazardous chemical wastes and liquid effluents are also addressed by describing the sites and canyons that are impacted. The review then focuses on the transport pathways addressed mainly in reports by Healy and Formerly Utilized Sites Remedial Action Program. Once the source terms and potential transport pathways are described, the dose assessment methods are addressed. Three major studies, the waste alternatives, Hansen and Rogers, and the Pantex Environmental Impact Statement, contributed to the current Los Alamos dose assessment methodology. Finally, the current Los Alamos groundwater, surface water, and environmental assessment models for these mesa top and canyon sites are described.

  2. Mechanical–biological treatment: Performance and potentials. An LCA of 8 MBT plants including waste characterization

    DEFF Research Database (Denmark)

    Montejo, Cristina; Tonini, Davide; Márquez, María del Carmen

    2013-01-01

    In the endeavour of avoiding presence of biodegradable waste in landfills and increasing recycling, mechanical–biological treatment (MBT) plants have seen a significant increase in number and capacity in the last two decades. The aim of these plants is separating and stabilizing the quickly...... biodegradable fraction of the waste as well as recovering recyclables from mixed waste streams. In this study the environmental performance of eight MBT-based waste management scenarios in Spain was assessed by means of life cycle assessment. The focus was on the technical and environmental performance...

  3. Cellular multiplets in directional solidification

    Energy Technology Data Exchange (ETDEWEB)

    Kopczynski, P.; Rappel, W.; Karma, A. [Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts 02115 (United States)

    1997-02-01

    We report the existence of new branches of steady state cellular structures in directional solidification. These structures consist of repeating cellular subunits, or multiplets, each containing a set of distinct cells separated by unequal grooves. A detailed numerical study of the symmetric model of directional solidification reveals that all multiplets bifurcate off the main singlet solution branch in two sets. Two points on the main branch, one corresponding to the onset of the Eckhaus instability at small cell spacing and the other to a fold of this branch at large spacing, are argued to be separate accumulation points for each set of multiplets. The set of structures bifurcating near the fold are morphologically similar to experimentally observed multiplets. In contrast, those bifurcating near the Eckhaus instability do not resemble experimental shapes. Furthermore, they are argued to be generically unstable. {copyright} {ital 1997} {ital The American Physical Society}

  4. Proceedings of the 1st workshop on radioactive waste treatment technologies, October 28, 1997 Taejon, Korea

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This proceedings describes the volume reduction of radioactive waste, the radioactive waste treatment technology, the decontamination and decommissioning, and the incineration and solidification of radioactive waste. Twenty two papers are submitted.

  5. Research on the Environmental Performance Evaluation of Electronic Waste Reverse Logistics Enterprise

    Science.gov (United States)

    Yang, Yu-Xiang; Chen, Fei-Yang; Tong, Tong

    According to the characteristic of e-waste reverse logistics, environmental performance evaluation system of electronic waste reverse logistics enterprise is proposed. We use fuzzy analytic hierarchy process method to evaluate the system. In addition, this paper analyzes the enterprise X, as an example, to discuss the evaluation method. It's important to point out attributes and indexes which should be strengthen during the process of ewaste reverse logistics and provide guidance suggestions to domestic e-waste reverse logistics enterprises.

  6. Test for Fauske and Associates to perform tube propagation experiments with simulated Hanford tank wastes

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, C.D.

    1996-02-01

    This test plan, prepared at Pacific Northwest National Laboratory for Westinghouse Hanford Company, provides guidance for performing tube propagation experiments on simulated Hanford tank wastes and on actual tank waste samples. Simulant compositions are defined and an experimental logic tree is provided for Fauske and Associates (FAI) to perform the experiments. From this guidance, methods and equipment for small-scale tube propagation experiments to be performed at the Hanford Site on actual tank samples will be developed. Propagation behavior of wastes will directly support the safety analysis (SARR) for the organic tanks. Tube propagation may be the definitive tool for determining the relative reactivity of the wastes contained in the Hanford tanks. FAI have performed tube propagation studies previously on simple two- and three-component surrogate mixtures. The simulant defined in this test plan more closely represents actual tank composition. Data will be used to support preparation of criteria for determining the relative safety of the organic bearing wastes.

  7. Data Package for Secondary Waste Form Down-Selection—Cast Stone

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R. Jeffrey; Westsik, Joseph H.

    2011-09-05

    Available literature on Cast Stone and Saltstone was reviewed with an emphasis on determining how Cast Stone and related grout waste forms performed in relationship to various criteria that will be used to decide whether a specific type of waste form meets acceptance criteria for disposal in the Integrated Disposal Facility (IDF) at Hanford. After the critical review of the Cast Stone/Saltstone literature, we conclude that Cast Stone is a good candidate waste form for further consideration. Cast stone meets the target IDF acceptance criteria for compressive strength, no free liquids, TCLP leachate are below the UTS permissible concentrations and leach rates for Na and Tc-99 are suiteably low. The cost of starting ingredients and equipment necessary to generate Cast Stone waste forms with secondary waste streams are low and the Cast Stone dry blend formulation can be tailored to accommodate variations in liquid waste stream compositions. The database for Cast Stone short-term performance is quite extensive compared to the other three candidate waste solidification processes. The solidification of liquid wastes in Cast Stone is a mature process in comparison to the other three candidates. Successful production of Cast Stone or Saltstone has been demonstrated from lab-scale monoliths with volumes of cm3 through m3 sized blocks to 210-liter sized drums all the way to the large pours into vaults at Savannah River. To date over 9 million gallons of low activity liquid waste has been solidified and disposed in concrete vaults at Savannah River.

  8. Chemical and mechanical performance properties for various final waste forms -- PSPI scoping study

    Energy Technology Data Exchange (ETDEWEB)

    Farnsworth, R.K.; Larsen, E.D.; Sears, J.W.; Eddy, T.L.; Anderson, G.L.

    1996-09-01

    The US DOE is obtaining data on the performance properties of the various final waste forms that may be chosen as primary treatment products for the alpha-contaminated low-level and transuranic waste at the INEL`s Transuranic Storage Area. This report collects and compares selected properties that are key indicators of mechanical and chemical durability for Portland cement concrete, concrete formed under elevated temperature and pressure, sulfur polymer cement, borosilicate glass, and various forms of alumino-silicate glass, including in situ vitrification glass and various compositions of iron-enriched basalt (IEB) and iron-enriched basalt IV (IEB4). Compressive strength and impact resistance properties were used as performance indicators in comparative evaluation of the mechanical durability of each waste form, while various leachability data were used in comparative evaluation of each waste form`s chemical durability. The vitrified waste forms were generally more durable than the non-vitrified waste forms, with the iron-enriched alumino-silicate glasses and glass/ceramics exhibiting the most favorable chemical and mechanical durabilities. It appears that the addition of zirconia and titania to IEB (forming IEB4) increases the leach resistance of the lanthanides. The large compositional ranges for IEB and IEB4 more easily accommodate the compositions of the waste stored at the INEL than does the composition of borosilicate glass. It appears, however, that the large potential variation in IEB and IEB4 compositions resulting from differing waste feed compositions can impact waste form durability. Further work is needed to determine the range of waste stream feed compositions and rates of waste form cooling that will result in acceptable and optimized IEB or IEB4 waste form performance. 43 refs.

  9. Feasibility study on the solidification of liquid low-level radioactive mixed waste in the inactive tank system at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Trussell, S. [Texas A and M Univ., College Station, TX (United States). Dept. of Civil Engineering; Spence, R.D. [Oak Ridge National Lab., TN (United States)

    1993-01-01

    A literature survey was conducted to help determine the feasibility of solidifying a liquid low-level radioactive mixed waste in the inactive tank system at Oak Ridge National Laboratory (ORNL). The goal of this report is to facilitate a decision on the disposition of these wastes by identifying any waste constituents that might (1) compromise the strength or stability of the waste form or (2) be highly leachable. Furthermore, its goal is to identify ways to circumvent interferences and to decrease the leachability of the waste constituents. This study has sought to provide an understanding of inhibition of cement set by identifying the fundamental chemical mechanisms by which this inhibition takes place. From this fundamental information, it is possible to draw some conclusions about the potential effects of waste constituents, even in the absence of particular studies on specific compounds.

  10. Incinerator performance: effects of changes in waste input and furnace operation on air emissions and residues

    DEFF Research Database (Denmark)

    Astrup, Thomas; Riber, Christian; Pedersen, Anne Juul

    2011-01-01

    Waste incineration can be considered a robust technology for energy recovery from mixed waste. Modern incinerators are generally able to maintain relatively stable performance, but changes in waste input and furnace operation may affect emissions. This study investigated how inorganic air emissio...... ranges of element transfer coefficients were provided as the basis for sensitivity analysis of life-cycle assessment (LCA) results involving waste incinerator technologies...... and residue composition at a full-scale incinerator were affected by known additions of specific waste materials to the normal municipal solid waste (MSW) input. Six individual experiments were carried out (% ww of total waste input): NaCl (0.5%), shoes (1.6%), automobile shredder waste (14%), batteries (0.......5%), poly(vinyl chloride) (5.5%) and chromate-cupper-arsenate impregnated wood (11%). Materials were selected based on chemical composition and potential for being included or excluded from the waste mix. Critical elements in the waste materials were identified based on comparison with six experiments...

  11. Performance of on-site Medical waste disinfection equipment in hospitals of Tabriz, Iran

    Directory of Open Access Journals (Sweden)

    Hassan Taghipour

    2016-10-01

    Full Text Available Background: The number of studies available on the performance of on-site medical waste treatment facilities is rare, to date. The aim of this study was to evaluate the performance of onsite medical waste treatment equipment in hospitals of Tabriz, Iran. Methods: A various range of the on-site medical waste disinfection equipment (autoclave, chemical disinfection, hydroclave, and dry thermal treatment was considered to select 10 out of 22 hospitals in Tabriz to be included in the survey. The apparatus were monitored mechanically, chemically, and biologically for a six months period in all of the selected hospitals. Results: The results of the chemical monitoring (Bowie-Dick tests indicated that 38.9% of the inspected autoclaves had operational problems in pre-vacuum, air leaks, inadequate steam penetration into the waste, and/or vacuum pump. The biological indicators revealed that about 55.55% of the samples were positive. The most of applied devices were not suitable for treating anatomical, pharmaceutical, cytotoxic, and chemical waste. Conclusion: Although on-site medical waste treating facilities have been installed in all the hospitals, the most of infectious-hazardous medical waste generated in the hospitals were deposited into a municipal solid waste landfill, without enough disinfection. The responsible authorities should stringently inspect and evaluate the operation of on-site medical waste treating equipment. An advanced off-site central facility with multi-treatment and disinfection equipment and enough capacity is recommended as an alternative.

  12. Determination of four acidic nonsteroidal anti-inflammatory drugs in wastewater samples by dispersive liquid-liquid microextraction based on solidification of floating organic droplet and high-performance liquid chromatography.

    Science.gov (United States)

    Beldean-Galea, Mihail Simion; Coman, Virginia; Thiébaut, Didier; Vial, Jérome

    2015-02-01

    A simple, environmentally friendly, and sensitive dispersive liquid-liquid microextraction based on solidification of floating organic droplet for the extraction of four acidic nonsteroidal anti-inflammatory drugs (ketoprofen, naproxen, ibuprofen, and diclofenac) from wastewater samples subsequent by high-performance liquid chromatography analysis was developed. The influence of extraction parameters such as pH, the effect of solution ionic strength, type of extraction solvent, disperser solvent, and extraction solvent volume were studied. High enrichment factors (283-302) were obtained through the developed method. The method provides good linearity (r > 0.999) in a concentration range of 1-100 μg/L, good intra- and inter-day precision (relative standard deviation < 7%) and low limits of quantification. The relative recoveries of the selected compounds were situated over 80% both in synthetic and real water samples. The developed method has been successfully applied for the analysis of the selected compounds in wastewater samples. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Challenges when Performing Economic Optimization of Waste Treatment

    DEFF Research Database (Denmark)

    Juul, Nina; Münster, Marie; Ravn, Hans

    2011-01-01

    on transport are one example but models focusing on energy production have also been developed as well as models which take into account the plants economies of scale, environmental impact, material recovery and social costs. Finally, models combining different criteria for selection of waste treatment methods...

  14. Chemically bonded phosphate ceramics for low-level mixed waste stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Singh, D.; Wagh, A.S.; Cunnane, J.C. [Argonne National Lab., IL (United States); Mayberry, J.L. [Science Applications International Corp., Idaho Falls, ID (United States)

    1994-12-31

    Novel chemically bonded phosphate ceramics (CBPCs) are being developed and fabricated for low-temperature stabilization and solidification of mixed waste streams which are amenable to conventional high-temperature stabilization processes due to presence of volatiles such as heavy metal chloride and fluorides and/or pyrophorics in the wastes. Phosphates of Mg, Mg-Na and Zr are being developed as candidate matrix materials. In this paper, we present the fabrication procedures of phosphate waste forms using surrogates compositions of three typical mixed wastes streams -- ash, cement sludges, and salts. The performance of the final waste forms such as compression strength, leachability of the contaminants, durability in aqueous environment were conducted. In addition, parameteric studies have been conducted to establish the optimal waste loading in a particular binder system. Based on the results, we present potential applications in the treatment of various mixed waste streams.

  15. Results from five years of treatability studies using hydraulic binders to stabilize low-level mixed waste at the INEL

    Energy Technology Data Exchange (ETDEWEB)

    Gering, K.L.; Schwendiman, G.L.

    1997-05-01

    This paper summarizes work involving bench-scale solidification of nonincinerable, land disposal restricted low-level mixed waste. Waste forms included liquids, sludges, and solids; treatment techniques included hydraulic systems (Portland cement with and without additives), proprietary commercial formulations, and sulphur polymer cement. Solidification was performed to immobilize hazardous heavy metals (including mercury, lead, chromium, and cadmium), and volatile and semivolatile organic compounds. Pretreatment options for mixed wastes are discussed, using a decision tree based on the form of mixed waste and the type of hazardous constituents. Hundreds of small concrete monoliths were formed for a variety of waste types. The experimental parameters used for the hydraulic concrete systems include the ratio of waste to dry binder (Portland cement, proprietary materials, etc.), the total percentage of water in concrete, and the amount of concrete additives. The only parameter that was used for the sulfur polymer-based monoliths is ratio of waste to binder. Optimum concrete formulations or {open_quotes}recipes{close_quotes} for a given type of waste were derived through this study, as based on results from the Toxicity Characteristic Leaching Procedure analyses and a free liquids test. Overall results indicate that high waste loadings in the concrete can be achieved while the monolithic mass maintains excellent resistance to leaching of heavy metals. In our study the waste loadings in the concrete generally fell within the range of 0.5 to 2.0 kg mixed waste per kg dry binder. Likewise, the most favorable amount of water in concrete, which is highly dependent upon the concrete constituents, was determined to be generally within the range of 300 to 330 g/kg (30-33% by weight). The results of this bench-scale study will find applicability at facilities where mixed or hazardous waste solidification is a planned or ongoing activity. 19 refs., 1 fig., 5 tabs.

  16. Environmental performance of an innovative waste refinery based on enzymatic treatment

    DEFF Research Database (Denmark)

    Tonini, Davide; Astrup, Thomas

    2011-01-01

    ) from the waste. The waste refinery was compared to alternative treatments such as incineration, bioreactor landfill and mechanical-biological treatment followed by utilization of the RDF (refuse-derived fuel) for energy. The performance of the waste refinery turned out to be comparable...... for virgin material and saving fossil resources. In this paper a life-cycle assessment of a pilot-scale waste refinery for the enzymatic treatment of municipal solid waste (MSW) is presented. The refinery produced a liquid (liquefied organic materials and paper) and a solid fraction (non-degradable materials...... with incineration for most environmental categories. Landfilling turned out to be the worst option with respect to most categories (especially energy-related such as GW). The refinery treatment has large margins of improvement with respect to the environmental performance. These are mainly associated...

  17. Low-level waste disposal performance assessments - Total source-term analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wilhite, E.L.

    1995-12-31

    Disposal of low-level radioactive waste at Department of Energy (DOE) facilities is regulated by DOE. DOE Order 5820.2A establishes policies, guidelines, and minimum requirements for managing radioactive waste. Requirements for disposal of low-level waste emplaced after September 1988 include providing reasonable assurance of meeting stated performance objectives by completing a radiological performance assessment. Recently, the Defense Nuclear Facilities Safety Board issued Recommendation 94-2, {open_quotes}Conformance with Safety Standards at Department of Energy Low-Level Nuclear Waste and Disposal Sites.{close_quotes} One of the elements of the recommendation is that low-level waste performance assessments do not include the entire source term because low-level waste emplaced prior to September 1988, as well as other DOE sources of radioactivity in the ground, are excluded. DOE has developed and issued guidance for preliminary assessments of the impact of including the total source term in performance assessments. This paper will present issues resulting from the inclusion of all DOE sources of radioactivity in performance assessments of low-level waste disposal facilities.

  18. Wavelength selection in directional solidification

    Energy Technology Data Exchange (ETDEWEB)

    Karma, A.

    1986-08-18

    Cell-spacing selection in directional solidification is investigated. An integral equation describing steady-state cells in the limit where the solute diffusion length is much larger than the cell spacing is derived and solved numerically by Newton's method. With surface tension and no crystalline anisotropy present the spatial periodicity of a one-dimensional array of cells with cusp singularities is found to be determined uniquely by a solvability condition. The inclusion of crystalline anisotropy has no other effect than to shift the value of the selected spacing.

  19. Finite element modelling of solidification phenomena

    Indian Academy of Sciences (India)

    The process of solidification process is complex in nature and the simulation of such process is required in industry before it is actually undertaken. Finite element method is used to simulate the heat transfer process accompanying the solidification process. The metal and the mould along with the air gap formation is ...

  20. Effect of thermosolutal convection on directional solidification

    Indian Academy of Sciences (India)

    The impact of thermosolutal convection during directional solidification is explored via results of numerical investigations. Results from fully transient numerical simulations of directional solidification in a differentially heated cavity under terrestrial conditions and Bridgman crystal growth in space are discussed. The pivotal ...

  1. Methodology to remediate a mixed waste site

    Energy Technology Data Exchange (ETDEWEB)

    Berry, J.B.

    1994-08-01

    In response to the need for a comprehensive and consistent approach to the complex issue of mixed waste management, a generalized methodology for remediation of a mixed waste site has been developed. The methodology is based on requirements set forth in the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Resource Conservation and Recovery Act (RCRA) and incorporates ``lessons learned`` from process design, remediation methodologies, and remediation projects. The methodology is applied to the treatment of 32,000 drums of mixed waste sludge at the Oak Ridge K-25 Site. Process technology options are developed and evaluated, first with regard to meeting system requirements and then with regard to CERCLA performance criteria. The following process technology options are investigated: (1) no action, (2) separation of hazardous and radioactive species, (3) dewatering, (4) drying, and (5) solidification/stabilization. The first two options were eliminated from detailed consideration because they did not meet the system requirements. A quantitative evaluation clearly showed that, based on system constraints and project objectives, either dewatering or drying the mixed waste sludge was superior to the solidification/stabilization process option. The ultimate choice between the drying and the dewatering options will be made on the basis of a technical evaluation of the relative merits of proposals submitted by potential subcontractors.

  2. Environmental performance of household waste management in Europe - An example of 7 countries.

    Science.gov (United States)

    Andreasi Bassi, Susanna; Christensen, Thomas H; Damgaard, Anders

    2017-11-01

    An attributional life cycle assessment (LCA) of the management of 1ton of household waste was conducted in accordance with ISO 14044:2006 and the ILCD Handbook for seven European countries, namely Germany, Denmark, France, UK, Italy, Poland and Greece, representing different household waste compositions, waste management practices, technologies, and energy systems. National data were collected from a range of sources regarding household waste composition, household sorting efficiency, collection, waste treatments, recycling, electricity and heat composition, and technological efficiencies. The objective was to quantify the environmental performance in the different countries, in order to analyze the sources of the main environmental impacts and national differences which affect the results. In most of the seven countries, household waste management provides environmental benefits when considering the benefits of recycling of materials and recovering and utilization of energy. Environmental benefits come from paper recycling and, to a lesser extent, the recycling of metals and glass. Waste-to-energy plants can lead to an environmental load (as in France) or a saving (Germany and Denmark), depending mainly on the composition of the energy being substituted. Sensitivity analysis and a data quality assessment identified a range of critical parameters, suggesting from where better data should be obtained. The study concluded that household waste management is environmentally the best in European countries with a minimum reliance on landfilling, also induced by the implementation of the Waste Hierarchy, though environmental performance does not correlate clearly with the rate of material recycling. From an environmental point of view, this calls for a change in the waste management paradigm, with less focus on where the waste is routed and more of a focus on the quality and utilization of recovered materials and energy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Investigation of Performance Analysis and Emission Characteristics of Waste Plastic Fuel

    Science.gov (United States)

    Ruban, M.; Ramasubramanian, S.; Pugazhenthi, R.; Sivaganesan

    2017-03-01

    Today the world is confronted with the twin crisis of fossil fuel depletion and stringent emission norms, because of the environmental awareness. The disposal and degradation of waste plastic is a major issue and scarcities of fuel were major focus area of the researchers. In this virtue the waste plastic fuel extraction makes more attention to the researchers. In this research work focused to find the performance of the waste plastic fuel and compared to diesel. The waste plastic fuel extract from thermal cracking method this process the polymer chains were breakdown into useful lower molecular weight compounds and it becomes plastic pyrolysis it can be utilized as a fuel. The properties of the waste plastic fuel is obtained by various testing process and which is analyze and compare with the fossil fuel diesel. It is found that almost it has similar properties to the diesel and almost all properties of the pyrolysis is closer to that of diesel. The characteristics of the pyrolysis were tested in the engine test bed. The pyrolysis / waste plastic fuel can be directly used in diesel engines over the entire load spectrum smoothly without any major modification. The performance of the waste plastic fuel / pyrolysis is evidenced that it is one of the best alternative fuel as well as the waste plastic can be converted into a useful fuel

  4. Performance assessment for continuing and future operations at solid waste storage area 6

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    This revised performance assessment (PA) for the continued disposal operations at Solid Waste Storage Area (SWSA) 6 on the Oak Ridge Reservation (ORR) has been prepared to demonstrate compliance with the performance objectives for low-level radioactive waste (LLW) disposal contained in the US Department of Energy (DOE) Order 5820.2A. This revised PA considers disposal operations conducted from September 26, 1988, through the projects lifetime of the disposal facility.

  5. Incorporation of evaporator concentrates mock-up waste in Brazilian bitumen; Incorporacao de rejeitos simulados de concentrado de evaporador em betume nacional

    Energy Technology Data Exchange (ETDEWEB)

    Guzella, Marcia Flavia Righi; Silva, Tania Valeria da [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil)]. E-mail: mfrg@cdtn.br; silvatv@cdtn.br

    2005-07-01

    The solidification of radioactive liquid waste generated in nuclear power plants is required by the safety standards for the transportation, storage and deposition. CDTN/CNEN has carried out studies and experimental research aiming at the solidification and stabilization of radioactive wastes on different matrixes, such as cement and bitumen, therefore contributing to the improvement of treatment processes of low and intermediate radioactive waste from NPPs in Brazil. Experiments with solidification of waste in national bitumen, using NPP Angra 2 mock-up equipment, were carried out at a pilot-scale at CDTN. The evaporator concentrates were simulated by boric acid solution, salts and corrosion products. Caesium chloride was added to the solution for comparison with former experiments that evaluated the influence of boron and sodium in the matrix resistance to leaching. This word presents the results of the waste form characterization, obtained according to the softening point, flash point, resistance to leaching and penetration tests, plus thermodifferencial analysis. The experiments were performed according to either ABNT or ISO standards. The correct characterization of the waste form is important not only for a safe disposal but also to obtain the necessary safety level during the operation of the radioactive waste bituminization system. (author)

  6. Equiaxed Dendritic Solidification Experiment (EDSE)

    Science.gov (United States)

    Beckermann, C.; Karma, A.; Steinbach, I.; deGroh, H. C., III

    2001-01-01

    The objective of the research is to quantitatively determine and understand the fundamental mechanisms that control the microstructural evolution during equiaxed dendritic solidification. A microgravity experiment will be conducted to obtain benchmark data on the transient growth and interaction of up to four equiaxed crystals of a pure and transparent metal analog (succinonitrile, SCN) under strictly diffusion-dominated conditions. Of interest in the experiment are the transient evolution of the primary and secondary dendrite tip speeds, the dendrite morphology and solid fraction, the tip selection criterion, and the temperature field in the melt for a range of interaction "strengths" between the crystals. The experiment extends the microgravity measurements of Glicksman and co-workers isothermal dendritic growth experiment (IDGE) for steady growth of a single dendrite to a case where growth transients are introduced due to thermal interactions between neighboring dendrites - a situation closer to actual casting conditions. Corresponding Earth-based experiments will be conducted to ascertain the influence of melt convection. The experiments are supported by a variety of analytical models and numerical simulations. The data will be used to develop and test theories of transient dendritic growth and the solidification of multiple interacting equiaxed crystals in a supercooled melt.

  7. Dynamic visualisation of municipal waste management performance in the EU using Ternary Diagram method.

    Science.gov (United States)

    Pomberger, R; Sarc, R; Lorber, K E

    2017-03-01

    This contribution describes the dynamic visualisation of European (EU 28) municipal waste management performance, using the Ternary Diagram Method. Municipal waste management performance depends primarily on three treatment categories: recycling & composting, incineration and landfilling. The framework of current municipal waste management including recycling targets, etc. is given by the Waste Framework Directive - 2008/98/EC. The proposed Circular Economy Package should stimulate Europe's transition towards more sustainable resources and energy oriented waste management. The Package also includes a revised legislative proposal on waste that sets ambitious recycling rates for municipal waste for 2025 (60%) and 2030 (65%). Additionally, the new calculation method for monitoring the attainment of the targets should be applied. In 2014, ca. 240 million tonnes of municipal waste were generated in the EU. While in 1995, 17% were recycled and composted, 14% incinerated and 64% landfilled, in 2014 ca. 71% were recovered but 28% landfilled only. Considering the treatment performance of the individual EU member states, the EU 28 can be divided into three groups, namely: "Recovery Countries", "Transition Countries" and "Landfilling Countries". Using Ternary Diagram Method, three types of visualization for the municipal waste management performance have been investigated and extensively described. Therefore, for better understanding of municipal waste management performance in the last 20years, dynamic visualisation of the Eurostat table-form data on all 28 member states of the EU has been carried out in three different ways: 1. "Performance Positioning" of waste management unit(s) at a specific date; 2. "Performance dynamics" over a certain time period and; 3. "Performance development" expressed as a track(s). Results obtained show that the Ternary Diagram Method is very well suited to be used for better understanding of past developments and coherences, for monitoring of

  8. Environmental performance of hydrothermal carbonization of four wet biomass waste streams at industry-relevant scales

    DEFF Research Database (Denmark)

    Owsianiak, Mikolaj; Ryberg, Morten; Renz, Michael

    2016-01-01

    Hydrothermal carbonization (HTC) of green waste, food waste, organic fraction of municipal solid waste (MSW), and digestate is assessed using life cycle assessment as a potential technology to treat biowaste. Water content of the biowaste and composition of the resulting hydrochar are important...... parameters influencing environmental performance. Hydrochar produced from green waste performs best and second best in respectively 2 and 10 out of 15 impact categories, including climate change, mainly due to low transportation needs of the biowaste and optimized pumping efficiency for the feedstock....... By contrast, hydrochar produced from the organic fraction of MSW performs best in 6 impact categories, but has high potential impacts on human health and ecosystems caused by emissions of toxic elements through ash disposal. The greatest potential for environmental optimization for the HTC technology...

  9. Performance of a Steel/Oxide Composite Waste Form for Combined Waste Steams from Advanced Electrochemical Processes

    Energy Technology Data Exchange (ETDEWEB)

    Indacochea, J. E. [Univ. of Illinois, Chicago, IL (United States); Gattu, V. K. [Univ. of Illinois, Chicago, IL (United States); Chen, X. [Univ. of Illinois, Chicago, IL (United States); Rahman, T. [Univ. of Illinois, Chicago, IL (United States)

    2017-06-15

    The results of electrochemical corrosion tests and modeling activities performed collaboratively by researchers at the University of Illinois at Chicago and Argonne National Laboratory as part of workpackage NU-13-IL-UIC-0203-02 are summarized herein. The overall objective of the project was to develop and demonstrate testing and modeling approaches that could be used to evaluate the use of composite alloy/ceramic materials as high-level durable waste forms. Several prototypical composite waste form materials were made from stainless steels representing fuel cladding, reagent metals representing metallic fuel waste streams, and reagent oxides representing oxide fuel waste streams to study the microstructures and corrosion behaviors of the oxide and alloy phases. Microelectrodes fabricated from small specimens of the composite materials were used in a series of electrochemical tests to assess the corrosion behaviors of the constituent phases and phase boundaries in an aggressive acid brine solution at various imposed surface potentials. The microstructures were characterized in detail before and after the electrochemical tests to relate the electrochemical responses to changes in both the electrode surface and the solution composition. The results of microscopic, electrochemical, and solution analyses were used to develop equivalent circuit and physical models representing the measured corrosion behaviors of the different materials pertinent to long-term corrosion behavior. This report provides details regarding (1) the production of the composite materials, (2) the protocol for the electrochemical measurements and interpretations of the responses of multi-phase alloy and oxide composites, (3) relating corrosion behaviors to microstructures of multi-phase alloys based on 316L stainless steel and HT9 (410 stainless steel was used as a substitute) with added Mo, Ni, and/or Mn, and (4) modeling the corrosion behaviors and rates of several alloy/oxide composite

  10. Performance Assessment for the Idaho National Laboratory Remote-Handled Low-Level Waste Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Annette L. Schafer; A. Jeffrey Sondrup; Arthur S. Rood

    2012-05-01

    This performance assessment for the Remote-Handled Low-Level Radioactive Waste Disposal Facility at the Idaho National Laboratory documents the projected radiological dose impacts associated with the disposal of low-level radioactive waste at the facility. This assessment evaluates compliance with the applicable radiological criteria of the U.S. Department of Energy and the U.S. Environmental Protection Agency for protection of the public and the environment. The calculations involve modeling transport of radionuclides from buried waste to surface soil and subsurface media, and eventually to members of the public via air, groundwater, and food chain pathways. Projections of doses are calculated for both offsite receptors and individuals who inadvertently intrude into the waste after site closure. The results of the calculations are used to evaluate the future performance of the low-level radioactive waste disposal facility and to provide input for establishment of waste acceptance criteria. In addition, one-factor-at-a-time, Monte Carlo, and rank correlation analyses are included for sensitivity and uncertainty analysis. The comparison of the performance assessment results to the applicable performance objectives provides reasonable expectation that the performance objectives will be met

  11. Data Packages for the Hanford Immobilized Low Activity Tank Waste Performance Assessment 2001 Version [SEC 1 THRU 5

    Energy Technology Data Exchange (ETDEWEB)

    MANN, F.M.

    2000-03-02

    Data package supporting the 2001 Immobilized Low-Activity Waste Performance Analysis. Geology, hydrology, geochemistry, facility, waste form, and dosimetry data based on recent investigation are provided. Verification and benchmarking packages for selected software codes are provided.

  12. Solidification/stabilization of technetium in cement-based grouts

    Energy Technology Data Exchange (ETDEWEB)

    Gilliam, T.M.; Bostick, W.D.; Spence, R.D.; Shoemaker, J.L. (Oak Ridge National Lab., TN (USA); Oak Ridge Gaseous Diffusion Plant, TN (USA); Oak Ridge National Lab., TN (USA); Oak Ridge Gaseous Diffusion Plant, TN (USA))

    1990-01-01

    Mixed low-level radioactive and chemically hazardous process treatment wastes from the Portsmouth Gaseous Diffusion Plant are stabilized by solidification in cement-based grouts. Conventional portland cement and fly ash grouts have been shown to be effective for retention of hydrolyzable metals (e.g., lead, cadmium, uranium and nickel) but are marginally acceptable for retention of radioactive Tc-99, which is present in the waste as the highly mobile pertechnate anion. Addition of ground blast furnace slag to the grout is shown to reduce the leachability of technetium by several orders of magnitude. The selective effect of slag is believed to be due to its ability to reduce Tc(VII) to the less soluble Tc(IV) species. 12 refs., 4 tabs.

  13. Updated Liquid Secondary Waste Grout Formulation and Preliminary Waste Form Qualification

    Energy Technology Data Exchange (ETDEWEB)

    Saslow, Sarah A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Russell, Renee L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Asmussen, Robert M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sahajpal, Rahul [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2017-07-01

    This report describes the results from liquid secondary waste grout (LSWG) formulation and cementitious waste form qualification tests performed by Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions, LLC (WRPS). New formulations for preparing a cementitious waste form from a high-sulfate liquid secondary waste stream simulant, developed for Effluent Management Facility (EMF) process condensates merged with low activity waste (LAW) caustic scrubber, and the release of key constituents (e.g. 99Tc and 129I) from these monoliths were evaluated. This work supports a technology development program to address the technology needs for Hanford Site Effluent Treatment Facility (ETF) liquid secondary waste (LSW) solidification and supports future Direct Feed Low-Activity Waste (DFLAW) operations. High-priority activities included simulant development, LSWG formulation, and waste form qualification. The work contained within this report relates to waste form development and testing and does not directly support the 2017 integrated disposal facility (IDF) performance assessment (PA). However, this work contains valuable information for use in PA maintenance past FY17, and for future waste form development efforts. The provided data should be used by (i) cementitious waste form scientists to further understanding of cementitious dissolution behavior, (ii) IDF PA modelers who use quantified constituent leachability, effective diffusivity, and partitioning coefficients to advance PA modeling efforts, and (iii) the U.S. Department of Energy (DOE) contractors and decision makers as they assess the IDF PA program. The results obtained help fill existing data gaps, support final selection of a LSWG waste form, and improve the technical defensibility of long-term waste form performance estimates.

  14. Dispersive liquid-phase microextraction with solidification of floating organic droplet coupled with high-performance liquid chromatography for the determination of Sudan dyes in foodstuffs and water samples.

    Science.gov (United States)

    Chen, Bo; Huang, Yuming

    2014-06-25

    Dispersive liquid-phase microextraction with solidification of floating organic drop (SFO-DLPME) is one of the most interesting sample preparation techniques developed in recent years. In this paper, a new, rapid, and efficient SFO-DLPME coupled with high-performance liquid chromatography (HPLC) was established for the extraction and sensitive detection of banned Sudan dyes, namely, Sudan I, Sudan II, Sudan III, and Sudan IV, in foodstuff and water samples. Various factors, such as the type and volume of extractants and dispersants, pH and volume of sample solution, extraction time and temperature, ion strength, and humic acid concentration, were investigated and optimized to achieve optimal extraction of Sudan dyes in one single step. After optimization of extraction conditions using 1-dodecanol as an extractant and ethanol as a dispersant, the developed procedure was applied for extraction of the target Sudan dyes from 2 g of food samples and 10 mL of the spiked water samples. Under the optimized conditions, all Sudan dyes could be easily extracted by the proposed SFO-DLPME method. Limits of detection of the four Sudan dyes obtained were 0.10-0.20 ng g(-1) and 0.03 μg L(-1) when 2 g of foodstuff samples and 10 mL of water samples were adopted, respectively. The inter- and intraday reproducibilities were below 4.8% for analysis of Sudan dyes in foodstuffs. The method was satisfactorily used for the detection of Sudan dyes, and the recoveries of the target for the spiked foodstuff and water samples ranged from 92.6 to 106.6% and from 91.1 to 108.6%, respectively. These results indicated that the proposed method is simple, rapid, sensitive, and suitable for the pre-concentration and detection of the target dyes in foodstuff samples.

  15. Performance of sand-lime products made with plastic waste

    Directory of Open Access Journals (Sweden)

    Nowek Milena

    2016-01-01

    Full Text Available The paper describes the studies on the sand-lime (silicate masonry units modified with recycled plastics in various forms: regranulate, regrind and powder. The following materials were examined: high impact polystyrene (HIPS and acrylonitrile butadiene styrene (ABS. The results of the functional properties tests, such as compressive strength, softening behavior, bulk density and water absorption are presented in the article. The microstructure of the products was analyzed using SEM and XRD methods.Obtained results show that the properties of modified product largely depend on the type, form and amount of used polymer. The highest compressive strength was achieved with 15% of HIPS regranulate in the product (by weight. ABS does not improve the strength of the sample, however, it does block the capillary action in the sand-lime product. The lowest softening coefficient was obtained in the sample modified with HIPS regranulate. The examined polymers contributed to decrease in bulk density of the samples as well as lowered their water absorption. The samples with pulverized polymer have the worst properties. All the results are compared with those of the traditional sand-lime bricks and sand-lime product modified with other additives. The analysis indicate that silicate masonry units with post-production and post-consumption plastic waste can possess interesting functional properties what brings a new potential possibility to dispose of still growing number of plastic waste.

  16. Determining the Performance of an Arid Zone Radioactive Waste Site Through Site Characterization, Modeling, and Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    B. L. Dozier; D. G. Levitt; M. J. Sully; and C. F. Lohrstorfer

    1999-03-09

    A strategy of site characterization, modeling, and monitoring are used to evaluate the performance of an interim cover at a low-level radioactive waste management site. The soil water migration papthway must be evaluated to assure the long-term isolation of low-level radioactive waste. Water balance studies using precision weighing lysimeters have been conducted for five years near the radioactive waste site ath the Nevada Test Site. The numerical flow models UNSAT-H and HYDRUS-2D were tested using the weighing lysimeter data and then used to evaluate various cover design issues including cover thickness, presence of vegetation, and monitoring system design.

  17. Annual Summary of Immobilized Low Activity Tank Waste (ILAW) Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    MANN, F M

    2000-05-01

    As required by the Department of Energy (DOE) order on radioactive waste management (DOE 1999a) as implemented by the Maintenance Plan for the Hanford Immobilized Low-Activity Tank Waste Performance Assessment (Mann 2000a), an annual summary of the adequacy of the Hanford Immobilized Low-Activity Tank Waste Performance Assessment (ILAW PA) must be submitted to DOE headquarters each year that a performance assessment is not submitted. Considering the results of data collection and analysis, the conclusions of the 1998 version of the ILAW PA (Mann 1998) as conditionally approved (DOE 1999b) remain valid, but new information indicates more conservatism in the results than previously estimated. A white paper (Mann 2000b) is attached as Appendix A to justify this statement. Recent ILAW performance estimates used on the waste form and geochemical data have resulted in increased confidence that the disposal of ILAW will meet performance objectives. The ILAW performance assessment program will continue to interact with science and technology activities, disposal facility design staff, and operations, as well as to continue to collect new waste form and disposal system data to further increase the understanding of the impacts of the disposal of ILAW. The next full performance assessment should be issued in the spring of 2001.

  18. Nuclear Waste Management quarterly progress report, October--December 1976

    Energy Technology Data Exchange (ETDEWEB)

    Platt, A.M. (comp.)

    1977-04-01

    Research topics on which progress is reported include decontamination and densification of chop-leach cladding residues, monitoring of effluents from waste solidification, TRU waste fixation, krypton solidification, /sup 14/C and /sup 129/I fixation, waste management system studies, organic complexes of fission products, characterization of 300 Area burial grounds, electropolishing as a decontamination technique, and decommissioning of Hanford facilities. 11 tables, 18 figures. (DLC)

  19. Fluid mechanics of directional solidification at reduced gravity

    Science.gov (United States)

    Chen, C. F.

    1992-01-01

    The primary objective of the proposed research is to provide additional groundbased support for the flight experiment 'Casting and Solidification Technology' (CAST). This experiment is to be performed in the International Microgravity Laboratory-1 (IML-1) scheduled to be flown on a space shuttle mission scheduled for 1992. In particular, we will provide data on the convective motion and freckle formation during directional solidification of NH4Cl from its aqueous solution at simulated parameter ranges equivalent to reducing the gravity from the sea-level value down to 0.1 g or lower. The secondary objectives of the proposed research are to examine the stability phenomena associated with the onset of freckles and the mechanisms for their subsequent growth and decline (to eventual demise of some) by state-of-the-art imaging techniques and to formulate mathematical models for the prediction of the observed phenomena.

  20. Effect of Mix Parameters on the Strength Performance of Waste Plastics Incorporated Concrete Mixes

    Directory of Open Access Journals (Sweden)

    Santhosh M. Malkapur

    2014-01-01

    Full Text Available Disposal of solid wastes has been a major problem all over the world. Out of all the different types of solid wastes, the major challenge of disposal is posed by the ever increasing volumes of plastic wastes. While several methods are in practice, producing newer useful materials by recycling of such plastic wastes is, by far, the best method of their disposal. One such possible method is to use the waste plastics as an ingredient in the production of the concrete mixes in the construction industry. The present study aims to investigate the relative contributions of the various mix parameters to the mechanical properties of concrete mixes produced with waste plastics as partial replacement (10–30% by volume to coarse aggregates. Initially, strength test results of a set of trial mixes, selected based on Taguchi’s design of experiments (DOE method are obtained. A detailed analysis of the experimental results is carried out to study the effect of using waste plastics as a partial replacement to coarse aggregates on the strength parameters of these concrete mixes. It is found that all these trial mixes have performed satisfactorily in terms of workability in the fresh state and strength properties in their hardened state.

  1. Improving Asphalt Mixture Performance by Partially Replacing Bitumen with Waste Motor Oil and Elastomer Modifiers

    Directory of Open Access Journals (Sweden)

    Sara Fernandes

    2017-08-01

    Full Text Available The environmental concern about waste generation and the gradual decrease of oil reserves has led the way to finding new waste materials that may partially replace the bitumens used in the road paving industry. Used motor oil from vehicles is a waste product that could answer that demand, but it can also drastically reduce the viscosity, increasing the asphalt mixture’s rutting potential. Therefore, polymer modification should be used in order to avoid compromising the required performance of asphalt mixtures when higher amounts of waste motor oil are used. Thus, this study was aimed at assessing the performance of an asphalt binder/mixture obtained by replacing part of a paving grade bitumen (35/50 with 10% waste motor oil and 5% styrene-butadiene-styrene (SBS as an elastomer modifier. A comparison was also made with the results of a previous study using a blend of bio-oil from fast pyrolysis and ground tire rubber modifier as a partial substitute for usual PG64-22 bitumen. The asphalt binders were tested by means of Fourier infrared spectra and dynamic shear rheology, namely by assessing their continuous high-performance grade. Later, the water sensitivity, fatigue cracking resistance, dynamic modulus and rut resistance performance of the resulting asphalt mixtures was evaluated. It was concluded that the new binder studied in this work improves the asphalt mixture’s performance, making it an excellent solution for paving works.

  2. Evolution of solidification texture during additive manufacturing

    National Research Council Canada - National Science Library

    Wei, H L; Mazumder, J; DebRoy, T

    2015-01-01

    Striking differences in the solidification textures of a nickel based alloy owing to changes in laser scanning pattern during additive manufacturing are examined based on theory and experimental data...

  3. Development of high-performance supercapacitor electrode derived from sugar industry spent wash waste.

    Science.gov (United States)

    Mahto, Ashesh; Gupta, Rajeev; Ghara, Krishna Kanta; Srivastava, Divesh N; Maiti, Pratyush; D, Kalpana; Rivera, Paul-Zavala; Meena, R; Nataraj, S K

    2017-10-15

    This study aims at developing supercapacitor materials from sugar and distillery industry wastes, thereby mediating waste disposal problem through reuse. In a two-step process, biomethanated spent wash (BMSW) was acid treated to produce solid waste sludge and waste water with significantly reduced total organic carbon (TOC) and biological oxygen demand (BOD) content. Further, waste sludge was directly calcined in presence of activating agent ZnCl2 in inert atmosphere resulting in high surface area (730-900m2g-1) carbon of unique hexagonal morphology. Present technique resulted in achieving two-faceted target of liquid-solid waste remediation and production of high-performance carbon material. The resulted high surface area carbon was tested in both three and two electrode systems. Electrochemical tests viz. cyclic voltammetry, galvanostatic charge-discharge and impedance measurement were carried out in aqueous KOH electrolyte yielding specific capacitance as high as 120Fg-1, whereas all solid supercapacitor devised using PVA/H3PO4 polyelectrolyte showed stable capacitance of 105Fg-1 at 0.2Ag-1. The presence of transition metal particles and hetero-atoms on carbon surface were confirmed by XPS, EDX and TEM analysis which enhanced the conductivity and imparted pseudocapacitance to some extent into the working electrode. The present study successfully demonstrated production of high-performance electrode material from dirtiest wastewater making process green, sustainable and economically viable. Copyright © 2017. Published by Elsevier B.V.

  4. Performance Characteristics of Waste Glass Powder Substituting Portland Cement in Mortar Mixtures

    Science.gov (United States)

    Kara, P.; Csetényi, L. J.; Borosnyói, A.

    2016-04-01

    In the present work, soda-lime glass cullet (flint, amber, green) and special glass cullet (soda-alkaline earth-silicate glass coming from low pressure mercury-discharge lamp cullet and incandescent light bulb borosilicate glass waste cullet) were ground into fine powders in a laboratory planetary ball mill for 30 minutes. CEM I 42.5N Portland cement was applied in mortar mixtures, substituted with waste glass powder at levels of 20% and 30%. Characterisation and testing of waste glass powders included fineness by laser diffraction particle size analysis, specific surface area by nitrogen adsorption technique, particle density by pycnometry and chemical analysis by X-ray fluorescence spectrophotometry. Compressive strength, early age shrinkage cracking and drying shrinkage tests, heat of hydration of mortars, temperature of hydration, X-ray diffraction analysis and volume stability tests were performed to observe the influence of waste glass powder substitution for Portland cement on physical and engineering properties of mortar mixtures.

  5. Performance of continuous stirred tank reactor (CSTR) on fermentative biohydrogen production from melon waste

    Science.gov (United States)

    Cahyari, K.; Sarto; Syamsiah, S.; Prasetya, A.

    2016-11-01

    This research was meant to investigate performance of continuous stirred tank reactor (CSTR) as bioreactor for producing biohydrogen from melon waste through dark fermentation method. Melon waste are commonly generated from agricultural processing stages i.e. cultivation, post-harvesting, industrial processing, and transportation. It accounted for more than 50% of total harvested fruit. Feedstock of melon waste was fed regularly to CSTR according to organic loading rate at value 1.2 - 3.6 g VS/ (l.d). Optimum condition was achieved at OLR 2.4 g VS/ (l.d) with the highest total gas volume 196 ml STP. Implication of higher OLR value is reduction of total gas volume due to accumulation of acids (pH 4.0), and lower substrate volatile solid removal. In summary, application of this method might valorize melon waste and generates renewable energy sources.

  6. Annual Summary of Immobilized Low Activity Tank Waste (ILAW) Performance Assessment for 2002

    Energy Technology Data Exchange (ETDEWEB)

    Mann, F. M.

    2002-08-01

    As required by the Department of Energy ( DOE), an annual summary of the adequacy of the Hanford Immobilized Low-Activity Tank Waste Performance Assessment (ILAW PA) is necessary in each year in which a full performance assessment is not issued.

  7. Investigation of Melting and Solidification of Thin Polycrystalline Silicon Films via Mixed-Phase Solidification

    Science.gov (United States)

    Wang, Ying

    Melting and solidification constitute the fundamental pathways through which a thin-film material is processed in many beam-induced crystallization methods. In this thesis, we investigate and leverage a specific beam-induced, melt-mediated crystallization approach, referred to as Mixed-Phase Solidification (MPS), to examine and scrutinize how a polycrystalline Si film undergoes the process of melting and solidification. On the one hand, we develop a more general understanding as to how such transformations can transpire in polycrystalline films. On the other hand, by investigating how the microstructure evolution is affected by the thermodynamic properties of the system, we experimentally reveal, by examining the solidified microstructure, fundamental information about such properties (i.e., the anisotropy in interfacial free energy). Specifically, the thesis consists of two primary parts: (1) conducting a thorough and extensive investigation of the MPS process itself, which includes a detailed characterization and analysis of the microstructure evolution of the film as it undergoes MPS cycles, along with additional development and refinement of a previously proposed thermodynamic model to describe the MPS melting-and-solidification process; and (2) performing MPS-based experiments that were systematically designed to reveal more information on the anisotropic nature of Si-SiO2 interfacial energy (i.e., sigma Si-SiO2). MPS is a recently developed radiative-beam-based crystallization technique capable of generating Si films with a combination of several sought-after microstructural characteristics. It was conceived, developed, and characterized within our laser crystallization laboratory at Columbia University. A preliminary thermodynamic model was also previously proposed to describe the overall melting and solidification behavior of a polycrystalline Si film during an MPS cycle, wherein the grain-orientation-dependent solid-liquid interface velocity is identified

  8. Uncertainty analysis for low-level radioactive waste disposal performance assessment at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Lee, D.W.; Yambert, M.W.; Kocher, D.C.

    1994-12-31

    A performance assessment of the operating Solid Waste Storage Area 6 (SWSA 6) facility for the disposal of low-level radioactive waste at the Oak Ridge National Laboratory has been prepared to provide the technical basis for demonstrating compliance with the performance objectives of DOE Order 5820.2A, Chapter 111.2 An analysis of the uncertainty incorporated into the assessment was performed which addressed the quantitative uncertainty in the data used by the models, the subjective uncertainty associated with the models used for assessing performance of the disposal facility and site, and the uncertainty in the models used for estimating dose and human exposure. The results of the uncertainty analysis were used to interpret results and to formulate conclusions about the performance assessment. This paper discusses the approach taken in analyzing the uncertainty in the performance assessment and the role of uncertainty in performance assessment.

  9. Hanford Tank Farms Waste Feed Flow Loop Phase VI: PulseEcho System Performance Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Denslow, Kayte M.; Bontha, Jagannadha R.; Adkins, Harold E.; Jenks, Jeromy WJ; Hopkins, Derek F.

    2012-11-21

    This document presents the visual and ultrasonic PulseEcho critical velocity test results obtained from the System Performance test campaign that was completed in September 2012 with the Remote Sampler Demonstration (RSD)/Waste Feed Flow Loop cold-test platform located at the Monarch test facility in Pasco, Washington. This report is intended to complement and accompany the report that will be developed by WRPS on the design of the System Performance simulant matrix, the analysis of the slurry test sample concentration and particle size distribution (PSD) data, and the design and construction of the RSD/Waste Feed Flow Loop cold-test platform.

  10. Carbon materials derived from waste tires as high-performance anodes in microbial fuel cells.

    Science.gov (United States)

    Chen, Wei; Feng, Huajun; Shen, Dongsheng; Jia, Yufeng; Li, Na; Ying, Xianbin; Chen, Ting; Zhou, Yuyang; Guo, Jiayun; Zhou, Mengjiao

    2017-10-15

    In this study, carbonized waste tires were directly used as a high-performance anode material in microbial fuel cells (MFCs). The effect of the pyrolysis temperature used for waste tire carbonization on the current output performance was investigated to determine the optimal pyrolysis temperature. Thermal gravimetric analysis/differential scanning calorimetry showed that tire carbonization started at 200°C and ended at about 500°C; the weight loss was about 64%. When used in an MFC, the electrode obtained from waste tires carbonized at 800°C gave a current density of 23.1±1.4Am(-2), which is much higher than that achieved with traditional graphite felt anodes (5.5±0.1Am(-2)). The results of this study will be useful in optimizing the design of carbonized waste tire anodes for enhancing MFC performances and will alleviate the environmental problems caused by waste tires. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Performance evaluation model of a pilot food waste collection system in Suzhou City, China.

    Science.gov (United States)

    Wen, Zongguo; Wang, Yuanjia; De Clercq, Djavan

    2015-05-01

    This paper analyses the food waste collection and transportation (C&T) system in a pilot project in Suzhou by using a novel performance evaluation method. The method employed to conduct this analysis involves a unified performance evaluation index containing qualitative and quantitative indicators applied to data from Suzhou City. Two major inefficiencies were identified: a) low system efficiency due to insufficient processing capacity of commercial food waste facilities; and b) low waste resource utilization due to low efficiency of manual sorting. The performance evaluation indicated that the pilot project collection system's strong points included strong economics, low environmental impact and low social impact. This study also shows that Suzhou's integrated system has developed a comprehensive body of laws and clarified regulatory responsibilities for each of the various government departments to solve the problems of commercial food waste management. Based on Suzhou's experience, perspectives and lessons can be drawn for other cities and areas where food waste management systems are in the planning stage, or are encountering operational problems. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Performance optimization of biological waste treatment by flotation clarification at a chemical manufacturing facility

    Energy Technology Data Exchange (ETDEWEB)

    Kerecz, B.J. [Air Products and Chemicals, Inc., Allentown, PA (United States); Miller, D.R. [Komline-Sanderson, Peapack, NJ (United States)

    1995-12-31

    Air Products and Chemicals, Inc., utilizes a deep-tank activated sludge wastewater treatment system with a dissolved air flotation clarifier (DAF) to effectively treat amine wastes containing residual organics, ammonia-nitrogen and organic nitrogen. The bio-system, a deep tank aeration system, produces a high quality final effluent low in biochemical oxygen demand (BOD), ammonia and organic nitrogen, turbidity and total suspended solids. Prior to installing the DAF, treatment performance was at risk with a gravity clarifier. Waste treatment performance was jeopardized by poor settling bio-flocs and uncontrollable solids-liquid separation problems within the gravity clarifier. The solids settleability problems resulted primarily from mixed liquor nitrogen supersaturation degassing in the clarifier. As a result of the degassing, biomass floated on the gravity clarifier or overflowed the effluent weir. As a result of biomass loss periodically organic carbon and total Kjeldahl nitrogen loadings had to be reduced in order to maintain optimal food-to-mass ratios. As biomass levels dropped within the aeration basin, waste treatment performance was at risk and waste loads had to be decreased causing waste inventories to increase in storage tanks.

  13. Does performance evaluation help public managers? A Balanced Scorecard approach in urban waste services.

    Science.gov (United States)

    Guimarães, Bernardo; Simões, Pedro; Marques, Rui Cunha

    2010-12-01

    The urban waste market has evolved significantly in the past decades, which among other changes, has led to the creation of new utilities and new business models. However, very few things have changed for the users. Urban waste collection remains mainly under the responsibility of local authorities and the charges paid by the users in most countries are very low compared to the provision costs. This situation forces the injection of public money into the system, encouraging the 'quiet-life' within the utilities and, therefore, inefficiency. The present study intends to analyze the potential for the application of the Balanced Scorecard (BSc) methodology into the waste utilities. After a comprehensive revision of the urban waste sector in Portugal, the methodology of BSc and its application in local public services is described and discussed. Focusing on implementation rather than on strategy, a set of performance indicators is proposed to be utilized in the different management models of waste utilities in Portugal: the municipalities, semi-autonomous utilities, municipal companies and mixed companies. This implementation is then exemplified through four case studies, one for each type of utility. This paper provides a flexible framework proposal to be applied to waste utilities operating both in Portugal and abroad. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Deployment of Performance Management Methodology as part of Liquid Waste Program at Savannah River Site - 12178

    Energy Technology Data Exchange (ETDEWEB)

    Prod' homme, A.; Drouvot, O.; Gregory, J. [AREVA, Paris (France); Barnes, B.; Hodges, B.; Hart, M. [SRR, Aiken, SC (United States)

    2012-07-01

    In 2009, Savannah River Remediation LLC (SRR) assumed the management lead of the Liquid Waste (LW) Program at the Savannah River Site (SRS). The four SRR partners and AREVA, as an integrated subcontractor are performing the ongoing effort to safely and reliably: - Close High Level Waste (HLW) storage tanks; - Maximize waste throughput at the Defense Waste Processing Facility (DWPF); - Process salt waste into stable final waste form; - Manage the HLW liquid waste material stored at SRS. As part of these initiatives, SRR and AREVA deployed a performance management methodology based on Overall Equipment Effectiveness (OEE) at the DWPF in order to support the required production increase. This project took advantage of lessons learned by AREVA through the deployment of Total Productive Maintenance and Visual Management methodologies at the La Hague reprocessing facility in France. The project also took advantage of measurement data collected from different steps of the DWPF process by the SRR team (Melter Engineering, Chemical Process Engineering, Laboratory Operations, Plant Operations). Today the SRR team has a standard method for measuring processing time throughout the facility, a reliable source of objective data for use in decision-making at all levels, and a better balance between engineering department goals and operational goals. Preliminary results show that the deployment of this performance management methodology to the LW program at SRS has already significantly contributed to the DWPF throughput increases and is being deployed in the Saltstone facility. As part of the liquid waste program on Savannah River Site, SRR committed to enhance production throughput of DWPF. Beyond technical modifications implemented at different location of the facility, SRR deployed performance management methodology based on OEE metrics. The implementation benefited from the experience gained by AREVA in its own facilities in France. OEE proved to be a valuable tool in order

  15. Waste Oil Burn-Off in Coast Guard Powerplants : Waste Oil Filtering Systems and Diesel Engine Performance

    Science.gov (United States)

    1976-06-01

    This report documents two tasks of a continuing study to determine the feasibility of burning waste lubricating oils in Coast Guard powerplants. The first task evaluated the effectiveness of two treatment devices for the clean-up of waste lubricating...

  16. Methods of calculating the post-closure performance of high-level waste repositories

    Energy Technology Data Exchange (ETDEWEB)

    Ross, B. (ed.)

    1989-02-01

    This report is intended as an overview of post-closure performance assessment methods for high-level radioactive waste repositories and is designed to give the reader a broad sense of the state of the art of this technology. As described here, ''the state of the art'' includes only what has been reported in report, journal, and conference proceedings literature through August 1987. There is a very large literature on the performance of high-level waste repositories. In order to make a review of this breadth manageable, its scope must be carefully defined. The essential principle followed is that only methods of calculating the long-term performance of waste repositories are described. The report is organized to reflect, in a generalized way, the logical order to steps that would be taken in a typical performance assessment. Chapter 2 describes ways of identifying scenarios and estimating their probabilities. Chapter 3 presents models used to determine the physical and chemical environment of a repository, including models of heat transfer, radiation, geochemistry, rock mechanics, brine migration, radiation effects on chemistry, and coupled processes. The next two chapters address the performance of specific barriers to release of radioactivity. Chapter 4 treats engineered barriers, including containers, waste forms, backfills around waste packages, shaft and borehole seals, and repository design features. Chapter 5 discusses natural barriers, including ground water systems and stability of salt formations. The final chapters address optics of general applicability to performance assessment models. Methods of sensitivity and uncertainty analysis are described in Chapter 6, and natural analogues of repositories are treated in Chapter 7. 473 refs., 19 figs., 2 tabs.

  17. Performance assessment for continuing and future operations at solid waste storage area 6. Appendices

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    This appendix provides the radionuclide inventory data used for the Solid Waste Storage Area (SWSA) 6 Performance Assessment (PA). The uncertainties in the radionuclide inventory data are also provided, along with the descriptions of the methods used to estimate the uncertainties.

  18. Repository performance assessment of waste forms from the electrometallurgical treatment of sodium-bonded spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Morris, E. E.; Fanning, T. H.; Feldman, E. E.; Petri, M. C.

    2000-03-20

    The ceramic and metal waste forms produced by electrometallurgical treatment of sodium-bonded spent nuclear fuel are undergoing evaluation as to how they will perform within the geologic repository which is proposed to be built at Yucca Mountain. An initial assessment, making use of preliminary degradation models for the waste forms, is described. The analyses are performed with a simplified version of the Total System Performance Assessment--Viability Assessment repository model. Results indicate that the ability of the ceramic and metal waste forms to retain radionuclides is similar to and sometimes better than defense high-level waste glass.

  19. 1-D diffusion based solidification model with volumetric expansion and shrinkage effect: A semi-analytical approach

    Science.gov (United States)

    Monde, Aniket D.; Chakraborty, Prodyut R.

    2017-10-01

    Volumetric expansion and shrinkage due to different densities of solid and liquid phases are common phenomena during solidification process. Simple analytical models addressing effect of volumetric expansion/shrinkage during solidification are rarely found. The few existing 1-D solidification models are valid only for semi-infinite domain with limitations of their application for finite domain size. The focus of the present work is to develop a 1-D semi-analytical solidification model addressing effects of volumetric expansion/shrinkage in a finite domain. The proposed semi-analytical scheme involves finding simultaneous solution of transient 1-D heat diffusion equations at solid and liquid domain coupled at the interface by Stefan condition. The change of the total domain length during solidification due to volumetric expansion/shrinkage is addressed by using mass conservation. For validation of the proposed model, solidification of water in a finite domain is studied without considering volumetric expansion/shrinkage effect and results are compared with those obtained from existing enthalpy updating based numerical model. After validation, case studies pertaining to volumetric expansion and shrinkage are performed considering solidification of water and paraffin respectively and physically consistent results are obtained. The study is relevant for understanding unidirectional crystal growth under the effect of controlled boundary condition.

  20. Polyethylene encapsulatin of nitrate salt wastes: Waste form stability, process scale-up, and economics

    Energy Technology Data Exchange (ETDEWEB)

    Kalb, P.D.; Heiser, J.H. III; Colombo, P.

    1991-07-01

    A polyethylene encapsulation system for treatment of low-level radioactive, hazardous, and mixed wastes has been developed at Brookhaven National Laboratory. Polyethylene has several advantages compared with conventional solidification/stabilization materials such as hydraulic cements. Waste can be encapsulated with greater efficiency and with better waste form performance than is possible with hydraulic cement. The properties of polyethylene relevant to its long-term durability in storage and disposal environments are reviewed. Response to specific potential failure mechanisms including biodegradation, radiation, chemical attack, flammability, environmental stress cracking, and photodegradation are examined. These data are supported by results from extensive waste form performance testing including compressive yield strength, water immersion, thermal cycling, leachability of radioactive and hazardous species, irradiation, biodegradation, and flammability. The bench-scale process has been successfully tested for application with a number of specific problem'' waste streams. Quality assurance and performance testing of the resulting waste form confirmed scale-up feasibility. Use of this system at Rocky Flats Plant can result in over 70% fewer drums processed and shipped for disposal, compared with optimal cement formulations. Based on the current Rocky Flats production of nitrate salt per year, polyethylene encapsulation can yield an estimated annual savings between $1.5 million and $2.7 million, compared with conventional hydraulic cement systems. 72 refs., 23 figs., 16 tabs.

  1. Source term model evaluations for the low-level waste facility performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Yim, M.S.; Su, S.I. [North Carolina State Univ., Raleigh, NC (United States)

    1995-12-31

    The estimation of release of radionuclides from various waste forms to the bottom boundary of the waste disposal facility (source term) is one of the most important aspects of LLW facility performance assessment. In this work, several currently used source term models are comparatively evaluated for the release of carbon-14 based on a test case problem. The models compared include PRESTO-EPA-CPG, IMPACTS, DUST and NEFTRAN-II. Major differences in assumptions and approaches between the models are described and key parameters are identified through sensitivity analysis. The source term results from different models are compared and other concerns or suggestions are discussed.

  2. A review of technologies and performances of thermal treatment systems for energy recovery from waste

    Energy Technology Data Exchange (ETDEWEB)

    Lombardi, Lidia, E-mail: lidia.lombardi@unicusano.it [Niccolò Cusano University, via Don Carlo Gnocchi, 3, 00166 Rome (Italy); Carnevale, Ennio [Industrial Engineering Department, University of Florence, via Santa Marta, 3, 50129 Florence (Italy); Corti, Andrea [Department of Information Engineering and Mathematics, University of Siena, via Roma, 56, 53100 (Italy)

    2015-03-15

    Highlights: • The topic of energy recovery from waste by thermal treatment is reviewed. • Combustion, gasification and pyrolysis were considered. • Data about energy recovery performances were collected and compared. • Main limitations to high values of energy performances were illustrated. • Diffusion of energy recovery from waste in EU, USA and other countries was discussed. - Abstract: The aim of this work is to identify the current level of energy recovery through waste thermal treatment. The state of the art in energy recovery from waste was investigated, highlighting the differences for different types of thermal treatment, considering combustion/incineration, gasification and pyrolysis. Also different types of wastes – Municipal Solid Waste (MSW), Refuse Derived Fuel (RDF) or Solid Refuse Fuels (SRF) and some typologies of Industrial Waste (IW) (sludge, plastic scraps, etc.) – were included in the analysis. The investigation was carried out mainly reviewing papers, published in scientific journals and conferences, but also considering technical reports, to gather more information. In particular the goal of this review work was to synthesize studies in order to compare the values of energy conversion efficiencies measured or calculated for different types of thermal processes and different types of waste. It emerged that the dominant type of thermal treatment is incineration associated to energy recovery in a steam cycle. When waste gasification is applied, the produced syngas is generally combusted in a boiler to generate steam for energy recovery in a steam cycle. For both the possibilities – incineration or gasification – cogeneration is the mean to improve energy recovery, especially for small scale plants. In the case of only electricity production, the achievable values are strongly dependent on the plant size: for large plant size, where advanced technical solutions can be applied and sustained from an economic point of view, net

  3. Interaction of Multiple Particles with a Solidification Front: From Compacted Particle Layer to Particle Trapping.

    Science.gov (United States)

    Saint-Michel, Brice; Georgelin, Marc; Deville, Sylvain; Pocheau, Alain

    2017-06-13

    The interaction of solidification fronts with objects such as particles, droplets, cells, or bubbles is a phenomenon with many natural and technological occurrences. For an object facing the front, it may yield various fates, from trapping to rejection, with large implications regarding the solidification pattern. However, whereas most situations involve multiple particles interacting with each other and the front, attention has focused almost exclusively on the interaction of a single, isolated object with the front. Here we address experimentally the interaction of multiple particles with a solidification front by performing solidification experiments of a monodisperse particle suspension in a Hele-Shaw cell with precise control of growth conditions and real-time visualization. We evidence the growth of a particle layer ahead of the front at a close-packing volume fraction, and we document its steady-state value at various solidification velocities. We then extend single-particle models to the situation of multiple particles by taking into account the additional force induced on an entering particle by viscous friction in the compacted particle layer. By a force balance model this provides an indirect measure of the repelling mean thermomolecular pressure over a particle entering the front. The presence of multiple particles is found to increase it following a reduction of the thickness of the thin liquid film that separates particles and front. We anticipate the findings reported here to provide a relevant basis to understand many complex solidification situations in geophysics, engineering, biology, or food engineering, where multiple objects interact with the front and control the resulting solidification patterns.

  4. Residential Waste

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Fruergaard, Thilde; Matsufuji, Y.

    2011-01-01

    Residential waste comes from residential areas with multi-family and single-family housing and includes four types of waste: household waste, garden waste, bulky waste and household hazardous waste. Typical unit generation rates, material composition, chemical composition and determining factors...... are discussed in this chapter. Characterizing residential waste is faced with the problem that many residences already divert some waste away from the official collection systems, for example performing home composting of vegetable waste and garden waste, having their bundled newspaper picked up by the scouts...... twice a year or bringing their used furniture to the flea markets organized by charity clubs. Thus, much of the data available on residential waste represents collected waste and not necessarily all generated waste. The latter can only be characterized by careful studies directly at the source...

  5. Performance assessment for a hypothetical low-level waste disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.S.; Rohe, M.J.; Ritter, P.D. [and others

    1997-01-01

    Disposing of low-level waste (LLW) is a concern for many states throughout the United States. A common disposal method is below-grade concrete vaults. Performance assessment analyses make predictions of contaminant release, transport, ingestion, inhalation, or other routes of exposure, and the resulting doses for various disposal methods such as the below-grade concrete vaults. Numerous assumptions are required to simplify the processes associated with the disposal facility to make predictions feasible. In general, these assumptions are made conservatively so as to underestimate the performance of the facility. The objective of this report is to describe the methodology used in conducting a performance assessment for a hypothetical waste facility located in the northeastern United States using real data as much as possible. This report consists of the following: (a) a description of the disposal facility and site, (b) methods used to analyze performance of the facility, (c) the results of the analysis, and (d) the conclusions of this study.

  6. Performance assessment for continuing and future operations at Solid Waste Storage Area 6

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This radiological performance assessment for the continued disposal operations at Solid Waste Storage Area 6 (SWSA 6) on the Oak Ridge Reservation (ORR) has been prepared to demonstrate compliance with the requirements of the US DOE. The analysis of SWSA 6 required the use of assumptions to supplement the available site data when the available data were incomplete for the purpose of analysis. Results indicate that SWSA 6 does not presently meet the performance objectives of DOE Order 5820.2A. Changes in operations and continued work on the performance assessment are expected to demonstrate compliance with the performance objectives for continuing operations at the Interim Waste Management Facility (IWMF). All other disposal operations in SWSA 6 are to be discontinued as of January 1, 1994. The disposal units at which disposal operations are discontinued will be subject to CERCLA remediation, which will result in acceptable protection of the public health and safety.

  7. Performance of mechanical biological treatment of residual municipal waste in Poland

    Science.gov (United States)

    den Boer, Emilia; Jędrczak, Andrzej

    2017-11-01

    The number and capacity of mechanical-biological treatment (MBT) plants in Europe increased significantly in the past two decades as a response to the legal obligation to limit the landfilling of biodegradable waste in landfills and to increase recycling and energy recovery from waste. The aim of these plants is to prepare residual municipal waste for recovery and disposal operations, including especially separation and stabilization of the easily biodegradable fraction (the biofraction). The final products of MBP technology are recyclables, stabilate, high calorific fraction which is used for the production of refuse derived fuel (RDF) and the remaining residual fraction. The shares of the output fractions, especially of the recyclables and RDF determine the overall efficiency of MBT technology in diverting waste from landfills. In this paper results of an assessment of one exemplary MBT plant are provided. The analysis was performed within a comparative study in which 20 selected MBT plants in Poland were subject to a detailed analysis, focusing, both at the design parameters as well as operational ones. The selected plant showed relatively higher overall materials recovery efficiency. With the view to circular economy targets, increased automation of the mechanical waste treatment will be required to support achieving high level diversion from landfills. The study reviled that stabilisation of biofraction should be improved by a better control of process conditions, especially moisture content.

  8. Preliminary Performance Assessment for the Waste Management Area C at the Hanford Site in Southeast Washington

    Energy Technology Data Exchange (ETDEWEB)

    Bergeron, Marcel P. [Washington River Protection Solutions LLC, Richland, WA (United States); Singleton, Kristin M. [Washington River Protection Solutions LLC, Richland, WA (United States); Eberlein, Susan J. [Washington River Protection Solutions LLC, Richland, WA (United States)

    2015-01-07

    A performance assessment (PA) of Single-Shell Tank (SST) Waste Management Area C (WMA C) located at the U.S. Department of Energy's (DOE) Hanford Site in southeastern Washington is being conducted to satisfy the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO), as well as other Federal requirements and State-approved closure plans and permits. The WMP C PA assesses the fate, transport, and impacts of radionuclides and hazardous chemicals within residual wastes left in tanks and ancillary equipment and facilities in their assumed closed configuration and the subsequent risks to humans into the far future. The part of the PA focused on radiological impacts is being developed to meet the requirements for a closure authorization under DOE Order 435.1 that includes a waste incidental to reprocessing determination for residual wastes remaining in tanks, ancillary equipment, and facilities. An additional part of the PA will evaluate human health and environmental impacts from hazardous chemical inventories in residual wastes remaining in WMA C tanks, ancillary equipment, and facilities needed to meet the requirements for permitted closure under RCRA.

  9. Energy performance of an integrated bio-and-thermal hybrid system for lignocellulosic biomass waste treatment.

    Science.gov (United States)

    Kan, Xiang; Yao, Zhiyi; Zhang, Jingxin; Tong, Yen Wah; Yang, Wenming; Dai, Yanjun; Wang, Chi-Hwa

    2017-03-01

    Lignocellulosic biomass waste, a heterogeneous complex of biodegradables and non-biodegradables, accounts for large proportion of municipal solid waste. Due to limitation of single-stage treatment, a two-stage hybrid AD-gasification system was proposed in this work, in which AD acted as pre-treatment to convert biodegradables into biogas followed by gasification converting solid residue into syngas. Energy performance of single and two-stage systems treating 3 typical lignocellulosic wastes was studied using both experimental and numerical methods. In comparison with conventional single-stage gasification treatment, this hybrid system could significantly improve the quality of produced gas for all selected biomass wastes and show its potential in enhancing total gas energy production by a maximum value of 27% for brewer's spent grain treatment at an organic loading rate (OLR) of 3gVS/L/day. The maximum overall efficiency of the hybrid system for horticultural waste treatment was 75.2% at OLR of 11.3gVS/L/day, 5.5% higher than conventional single-stage system. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Mechanical-biological treatment: performance and potentials. An LCA of 8 MBT plants including waste characterization.

    Science.gov (United States)

    Montejo, Cristina; Tonini, Davide; Márquez, María del Carmen; Astrup, Thomas Fruergaard

    2013-10-15

    In the endeavour of avoiding presence of biodegradable waste in landfills and increasing recycling, mechanical-biological treatment (MBT) plants have seen a significant increase in number and capacity in the last two decades. The aim of these plants is separating and stabilizing the quickly biodegradable fraction of the waste as well as recovering recyclables from mixed waste streams. In this study the environmental performance of eight MBT-based waste management scenarios in Spain was assessed by means of life cycle assessment. The focus was on the technical and environmental performance of the MBT plants. These widely differed in type of biological treatment and recovery efficiencies. The results indicated that the performance is strongly connected with energy and materials recovery efficiency. The recommendation for upgrading and/or commissioning of future plants is to optimize materials recovery through increased automation of the selection and to prioritize biogas-electricity production from the organic fraction over direct composting. The optimal strategy for refuse derived fuel (RDF) management depends upon the environmental compartment to be prioritized and the type of marginal electricity source in the system. It was estimated that, overall, up to ca. 180-190 kt CO2-eq. y(-1) may be saved by optimizing the MBT plants under assessment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Non newtonian annular alloy solidification in mould

    Energy Technology Data Exchange (ETDEWEB)

    Moraga, Nelson O.; Garrido, Carlos P. [Universidad de La Serena, Departamento de Ingenieria Mecanica, La Serena (Chile); Castillo, Ernesto F. [Universidad de Santiago de Chile, Departamento de Ingenieria Mecanica, Santiago (Chile)

    2012-08-15

    The annular solidification of an aluminium-silicon alloy in a graphite mould with a geometry consisting of horizontal concentric cylinders is studied numerically. The analysis incorporates the behavior of non-Newtonian, pseudoplastic (n=0.2), Newtonian (n=1), and dilatant (n=1.5) fluids. The fluid mechanics and heat transfer coupled with a transient model of convection diffusion are solved using the finite volume method and the SIMPLE algorithm. Solidification is described in terms of a liquid fraction of a phase change that varies linearly with temperature. The final results make it possible to infer that the fluid dynamics and heat transfer of solidification in an annular geometry are affected by the non-Newtonian nature of the fluid, speeding up the process when the fluid is pseudoplastic. (orig.)

  12. Non Newtonian annular alloy solidification in mould

    Science.gov (United States)

    Moraga, Nelson O.; Castillo, Ernesto F.; Garrido, Carlos P.

    2012-08-01

    The annular solidification of an aluminium-silicon alloy in a graphite mould with a geometry consisting of horizontal concentric cylinders is studied numerically. The analysis incorporates the behavior of non-Newtonian, pseudoplastic ( n = 0.2), Newtonian ( n = 1), and dilatant ( n = 1.5) fluids. The fluid mechanics and heat transfer coupled with a transient model of convection diffusion are solved using the finite volume method and the SIMPLE algorithm. Solidification is described in terms of a liquid fraction of a phase change that varies linearly with temperature. The final results make it possible to infer that the fluid dynamics and heat transfer of solidification in an annular geometry are affected by the non-Newtonian nature of the fluid, speeding up the process when the fluid is pseudoplastic.

  13. Rapid solidification of Nb-base alloys

    Science.gov (United States)

    Gokhale, A. B.; Javed, K. R.; Abbaschian, G. J.; Lewis, R. E.

    1988-01-01

    New Nb-base alloys are of interest for aerospace structural applications at high temperatures, viz, 800 to 1650 C. Fundamental information regarding the effects of rapid solidification in achieving greatly refined microstructures, extended solid solubility, suppression of embrittling equilibrium phases, and formation of new phases is desired in a number of Nb-X alloys. The microstructures and selected properties of Nb-Si and other Nb-base alloys are presented for materials both rapidly quenched from the equilibrium liquidus and rapidly solidified following deep supercooling. Electromagnetic levitation was used to achieve melting and supercooling in a containerless inert gas environment. A variety of solidification conditions were employed including splatting or drop casting of supercooled samples. The morphology and composition of phases formed are discussed in terms of both solidification history and bulk composition.

  14. Data used in preliminary performance assessment of the Waste Isolation Pilot Plant (1990)

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P (Sandia National Labs., Albuquerque, NM (USA)); Luzzolino, H. (Geo-Centers, Inc., Albuquerque, NM (USA)); Sandha, J.S. (Science Applications International Corp., Albuquerque, NM (USA))

    1990-12-01

    This report documents the data available as of August 1990 and used by the Performance Assessment Division of Sandia National Laboratories in its December 1990 preliminary performance assessment of the Waste Isolation Pilot Plant (WIPP). Parameter values are presented in table form for the geologic subsystem, engineered barriers, borehole flow properties, climate variability, and intrusion characteristics. Sources for the data and a brief discussion of each parameter are provided. 101 refs., 72 figs., 21 tabs.

  15. Nuclear Energy Advanced Modeling and Simulation (NEAMS) Waste Integrated Performance and Safety Codes (IPSC) : FY10 development and integration.

    Energy Technology Data Exchange (ETDEWEB)

    Criscenti, Louise Jacqueline; Sassani, David Carl; Arguello, Jose Guadalupe, Jr.; Dewers, Thomas A.; Bouchard, Julie F.; Edwards, Harold Carter; Freeze, Geoffrey A.; Wang, Yifeng; Schultz, Peter Andrew

    2011-02-01

    This report describes the progress in fiscal year 2010 in developing the Waste Integrated Performance and Safety Codes (IPSC) in support of the U.S. Department of Energy (DOE) Office of Nuclear Energy Advanced Modeling and Simulation (NEAMS) Campaign. The goal of the Waste IPSC is to develop an integrated suite of computational modeling and simulation capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive waste storage or disposal system. The Waste IPSC will provide this simulation capability (1) for a range of disposal concepts, waste form types, engineered repository designs, and geologic settings, (2) for a range of time scales and distances, (3) with appropriate consideration of the inherent uncertainties, and (4) in accordance with robust verification, validation, and software quality requirements. Waste IPSC activities in fiscal year 2010 focused on specifying a challenge problem to demonstrate proof of concept, developing a verification and validation plan, and performing an initial gap analyses to identify candidate codes and tools to support the development and integration of the Waste IPSC. The current Waste IPSC strategy is to acquire and integrate the necessary Waste IPSC capabilities wherever feasible, and develop only those capabilities that cannot be acquired or suitably integrated, verified, or validated. This year-end progress report documents the FY10 status of acquisition, development, and integration of thermal-hydrologic-chemical-mechanical (THCM) code capabilities, frameworks, and enabling tools and infrastructure.

  16. E AREA LOW LEVEL WASTE FACILITY DOE 435.1 PERFORMANCE ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Wilhite, E

    2008-03-31

    This Performance Assessment for the Savannah River Site E-Area Low-Level Waste Facility was prepared to meet requirements of Chapter IV of the Department of Energy Order 435.1-1. The Order specifies that a Performance Assessment should provide reasonable assurance that a low-level waste disposal facility will comply with the performance objectives of the Order. The Order also requires assessments of impacts to water resources and to hypothetical inadvertent intruders for purposes of establishing limits on radionuclides that may be disposed near-surface. According to the Order, calculations of potential doses and releases from the facility should address a 1,000-year period after facility closure. The point of compliance for the performance measures relevant to the all pathways and air pathway performance objective, as well as to the impact on water resources assessment requirement, must correspond to the point of highest projected dose or concentration beyond a 100-m buffer zone surrounding the disposed waste following the assumed end of active institutional controls 100 years after facility closure. During the operational and institutional control periods, the point of compliance for the all pathways and air pathway performance measures is the SRS boundary. However, for the water resources impact assessment, the point of compliance remains the point of highest projected dose or concentration beyond a 100-m buffer zone surrounding the disposed waste during the operational and institutional control periods. For performance measures relevant to radon and inadvertent intruders, the points of compliance are the disposal facility surface for all time periods and the disposal facility after the assumed loss of active institutional controls 100 years after facility closure, respectively. The E-Area Low-Level Waste Facility is located in the central region of the SRS known as the General Separations Area. It is an elbow-shaped, cleared area, which curves to the northwest

  17. X-Ray Radiographic Observation of Directional Solidification Under Microgravity: XRMON-GF Experiments on MASER12 Sounding Rocket Mission

    Science.gov (United States)

    Reinhart, G.; NguyenThi, H.; Bogno, A.; Billia, B.; Houltz, Y.; Loth, K.; Voss, D.; Verga, A.; dePascale, F.; Mathiesen, R. H.; hide

    2012-01-01

    The European Space Agency (ESA) - Microgravity Application Promotion (MAP) programme entitled XRMON (In situ X-Ray MONitoring of advanced metallurgical processes under microgravity and terrestrial conditions) aims to develop and perform in situ X-ray radiography observations of metallurgical processes in microgravity and terrestrial environments. The use of X-ray imaging methods makes it possible to study alloy solidification processes with spatio-temporal resolutions at the scales of relevance for microstructure formation. XRMON has been selected for MASER 12 sounding rocket experiment, scheduled in autumn 2011. Although the microgravity duration is typically six minutes, this short time is sufficient to investigate a solidification experiment with X-ray radiography. This communication will report on the preliminary results obtained with the experimental set-up developed by SSC (Swedish Space Corporation). Presented results dealing with directional solidification of Al-Cu confirm the great interest of performing in situ characterization to analyse dynamical phenomena during solidification processes.

  18. Quantitative performance targets by using balanced scorecard system: application to waste management and public administration.

    Science.gov (United States)

    Mendes, Paula; Nunes, Luis Miguel; Teixeira, Margarida Ribau

    2014-09-01

    This article demonstrates how decision-makers can be guided in the process of defining performance target values in the balanced scorecard system. We apply a method based on sensitivity analysis with Monte Carlo simulation to the municipal solid waste management system in Loulé Municipality (Portugal). The method includes two steps: sensitivity analysis of performance indicators to identify those performance indicators with the highest impact on the balanced scorecard model outcomes; and sensitivity analysis of the target values for the previously identified performance indicators. Sensitivity analysis shows that four strategic objectives (IPP1: Comply with the national waste strategy; IPP4: Reduce nonrenewable resources and greenhouse gases; IPP5: Optimize the life-cycle of waste; and FP1: Meet and optimize the budget) alone contribute 99.7% of the variability in overall balanced scorecard value. Thus, these strategic objectives had a much stronger impact on the estimated balanced scorecard outcome than did others, with the IPP1 and the IPP4 accounting for over 55% and 22% of the variance in overall balanced scorecard value, respectively. The remaining performance indicators contribute only marginally. In addition, a change in the value of a single indicator's target value made the overall balanced scorecard value change by as much as 18%. This may lead to involuntarily biased decisions by organizations regarding performance target-setting, if not prevented with the help of methods such as that proposed and applied in this study. © The Author(s) 2014.

  19. A moving boundary solution for solidification of lava lake and ...

    Indian Academy of Sciences (India)

    During the solidification of a lava lake heat is released convectively from the top surface as well as conductively into the country rock from the base, leading to non-uniform solidification. The upper solidified layer grows at a faster rate than the lower solidified layer. Similarly, solidification of magma intrusion within the crust is ...

  20. Process envelopes for stabilisation/solidification of contaminated soil using lime-slag blend.

    Science.gov (United States)

    Kogbara, Reginald B; Yi, Yaolin; Al-Tabbaa, Abir

    2011-09-01

    Stabilisation/solidification (S/S) has emerged as an efficient and cost-effective technology for the treatment of contaminated soils. However, the performance of S/S-treated soils is governed by several intercorrelated variables, which complicates the optimisation of the treatment process design. Therefore, it is desirable to develop process envelopes, which define the range of operating variables that result in acceptable performance. In this work, process envelopes were developed for S/S treatment of contaminated soil with a blend of hydrated lime (hlime) and ground granulated blast furnace slag (GGBS) as the binder (hlime/GGBS = 1:4). A sand contaminated with a mixture of heavy metals and petroleum hydrocarbons was treated with 5%, 10% and 20% binder dosages, at different water contents. The effectiveness of the treatment was assessed using unconfined compressive strength (UCS), permeability, acid neutralisation capacity and contaminant leachability with pH, at set periods. The UCS values obtained after 28 days of treatment were up to ∼800 kPa, which is quite low, and permeability was ∼10(-8) m/s, which is higher than might be required. However, these values might be acceptable in some scenarios. The binder significantly reduced the leachability of cadmium and nickel. With the 20% dosage, both metals met the waste acceptance criteria for inert waste landfill and relevant environmental quality standards. The results show that greater than 20% dosage would be required to achieve a balance of acceptable mechanical and leaching properties. Overall, the process envelopes for different performance criteria depend on the end-use of the treated material.

  1. Nuclear waste management. Quarterly progress report, July--September 1978

    Energy Technology Data Exchange (ETDEWEB)

    Platt, A.M.; Powell, J.A. (comps.)

    1979-01-01

    Research on the following is reported: decontamination and densification of chop-leach cladding residues; monitoring methods for particulate and gaseous effluents from waste solidification processes; TRU waste immobilization; krypton solidification; /sup 14/C and /sup 129/I fixation; waste management system studies; waste management safety studies; waste isolation safety assessment; well logging instrumentation for shallow land burial; monitoring and physical characteriztion of unsaturated zone transport; detection and characterization of mobile organic complexes of fission products; and electropolishing for surface decontamination of metals. 21 figures, 17 tables.

  2. Evaluation of performance indicators applied to a material recovery facility fed by mixed packaging waste.

    Science.gov (United States)

    Mastellone, Maria Laura; Cremiato, Raffaele; Zaccariello, Lucio; Lotito, Roberta

    2017-06-01

    Most of the integrated systems for municipal solid waste management aim to increase the recycling of secondary materials by means of physical processes including sorting, shredding and reprocessing. Several restrictions prevent from reaching a very high material recycling efficiency: the variability of the composition of new-marketed materials used for packaging production and its shape and complexity are critical issues. The packaging goods are in fact made of different materials (aluminium, polymers, paper, etc.), possibly assembled, having different shape (flat, cylindrical, one-dimensional, etc.), density, colours, optical properties and so on. These aspects limit the effectiveness and efficiency of the sorting and reprocessing plants. The scope of this study was to evaluate the performance of a large scale Material Recovery Facility (MRF) by utilizing data collected during a long period of monitoring. The database resulted from the measured data has been organized in four sections: (1) data related to the amount and type of inlet waste; (2) amount and composition of output products and waste; (3) operating data (such as worked hours for shift, planned and unscheduled maintenance time, setting parameters of the equipment, and energy consumption for shift); (4) economic data (value of each product, disposal price for the produced waste, penalty for non-compliance of products and waste, etc.). A part of this database has been utilized to build an executive dashboard composed by a set of performance indicators suitable to measure the effectiveness and the efficiency of the MRF operations. The dashboard revealed itself as a powerful tool to support managers and engineers in their decisions in respect to the market demand or compliance regulation variation as well as in the designing of the lay-out improvements. The results indicated that the 40% of the input waste was recovered as valuable products and that a large part of these (88%) complied with the standards of

  3. PERFORMANCE TESTING OF THE NEXT-GENERATION CSSX SOLVENT WITH ACTUAL SRS TANK WASTE

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, R.; Peters, T.; Crowder, M.; Fink, S.

    2011-11-01

    Efforts are underway to qualify the Next-Generation Solvent for the Caustic Side Solvent Extraction (CSSX) process. Researchers at multiple national laboratories have been involved in this effort. As part of the effort to qualify the solvent extraction system at the Savannah River Site (SRS), SRNL performed a number of tests at various scales. First, SRNL completed a series of batch equilibrium, or Extraction-Scrub-Strip (ESS), tests. These tests used {approx}30 mL of Next-Generation Solvent and either actual SRS tank waste, or waste simulant solutions. The results from these cesium mass transfer tests were used to predict solvent behavior under a number of conditions. At a larger scale, SRNL assembled 12 stages of 2-cm (diameter) centrifugal contactors. This rack of contactors is structurally similar to one tested in 2001 during the demonstration of the baseline CSSX process. Assembly and mechanical testing found no issues. SRNL performed a nonradiological test using 35 L of cesium-spiked caustic waste simulant and 39 L of actual tank waste. Test results are discussed; particularly those related to the effectiveness of extraction.

  4. The role of laboratory analog experiments in assessing the performance of waste package materials

    Energy Technology Data Exchange (ETDEWEB)

    Cunnane, J.C.; Bates, J.K.

    1990-12-31

    There is an immediate need to begin to validate models that can be used for assessing the performance of waste package materials in an unsaturated repository environment. This paper examines available testing information and testing approaches that could support validation of models for engineering barrier system (EBS) radionuclide release. The content is presented in the context of the general methodology that has been proposed for validating performance assessment models. Available experimental observations are used to test some of the EBS release rate modeling premises. These observations include evidence of fluid film formation on waste glass surfaces in isothermal humid environments, accelerated waste glass reaction rates under repository service conditions of large glass surface area to water volume ratio, and mobilization of radionuclides as solutes and colloids. It is concluded that some important modeling premises may not be consistent with available experimental information. However, it is also concluded that future laboratory testing, which simulates the integrated waste package systems, is needed to evaluate the significance of these inconsistencies and to test the system level models. A small-scale apparatus which was developed and tested to examine the feasibility of laboratory analog testing for the unsaturated Yucca Mountain repository environment is described. 16 refs., 4 figs., 1 tab.

  5. The Effect of Soy Sauce Waste in Ration on Performance of Mojosari Duck

    Directory of Open Access Journals (Sweden)

    G. A. A. Larasati

    2017-06-01

    Full Text Available The purpose of study was to determined the effect of soy sauce waste in ration in the ration on the performance of Mojosari duck. The materials used were 240 of Mojosari which are 20 weeks olds with average body weight 1,385.0 ± 130.85 grams (CV = 9.44%. Feed ingredients used were, rice bran, soybean meal, yellow corn, fish meal, pollard and premix. The design that used was Completely Randomized Design (CRD with 4 treatments and 6 replications.The treatment applied soy sauce waste at level 5, 7,5 and 10%. The parameters observed were consumption, egg production, feed conversion. The data were analyzed by analysis of variance with F test. The results showed that soy sauce waste did not effected on performance (consumption of ration, egg production, ration conversion of Mojosari duck. The conclusion of this research is soy sauce waste be used as feed stuff of Mojosari duck ration until level 10%.

  6. Sulfur Polymer Stabilization/Solidification Treatability Study of Mercury Contaminated Soil from the Y-12 Site

    Energy Technology Data Exchange (ETDEWEB)

    Kalb P.; Milian, L.; Yim, S. P.

    2012-11-30

    As a result of past operations, the Department of Energy’s (DOE) Oak Ridge Y-12 National Security Complex (Y-12 Plant) has extensive mercury-contamination in building structures, soils, storm sewer sediments, and stream sediments, which are a source of pollution to the local ecosystem. Because of mercury’s toxicity and potential impacts on human health and the environment, DOE continues to investigate and implement projects to support the remediation of the Y-12 site.URS and #9122;CH2M Oak Ridge LLC (UCOR) under its prime contract with DOE has cleanup responsibilities on the DOE Oak Ridge Reservation and is investigating potential mercury-contaminated soil treatment technologies through an agreement with Babcock and Wilcox (B and W) Y-12, the Y-12 operating contractor to DOE. As part of its investigations, UCOR has subcontracted with Brookhaven National Laboratory (BNL) to conduct laboratory-scale studies evaluating the applicability of the Sulfur Polymer Stabilization/Solidification (SPSS) process using surrogate and actual mixed waste Y-12 soils containing mercury (Hg) at 135, 2,000, and 10,000 ppm.SPSS uses a thermoplastic sulfur binder to convert Hg to stable mercury sulfide (HgS) and solidifies the chemically stable product in a monolithic solid final waste form to reduce dispersion and permeability. Formulations containing 40 – 60 dry wt% Y-12 soil were fabricated and samples were prepared in triplicate for Environmental Protection Agency Toxicity Characteristic Leaching Procedure (TCLP) testing by an independent laboratory. Those containing 50 and 60 wt% soil easily met the study criteria for maximum allowable Hg concentrations (47 and 1 ppb, respectively compared with the TCLP limit of 200 ppb Hg). The lowest waste loading of 40 wt% yielded TCLP Hg concentrations slightly higher (240 ppb) than the allowable limit. Since the Y-12 soil tended to form clumps, the improved leaching at higher waste loadings was probably due to reduction in particle size

  7. Annual summary of Immobilized Low-Activity Waste (ILAW) Performance Assessment for 2003 Incorporating the Integrated Disposal Facility Concept

    Energy Technology Data Exchange (ETDEWEB)

    MANN, F M

    2003-09-01

    To Erik Olds 09/30/03 - An annual summary of the adequacy of the Hanford Immobilized Low-Activity Tank Waste Performance Assessment (ILAW PA) is necessary in each year in which a full performance assessment is not issued.

  8. Solidification of hipereutectoid high speed steel for rolls

    Directory of Open Access Journals (Sweden)

    J. Gontarev

    2011-01-01

    Full Text Available This work presents results of microstructural development through solidification, heat treated processes and characterization of two low-alloyed hypereutectoid alloys, emphasizing the effects of the alloy chemical composition. Samples of different compositions were prepared by melting in the induction furnace. The microstructural difference of the different HSS steels will affect the performance of the end products. The main features of the as cast microstructure are the distribution and morphology of eutectic carbides which have been obtained through progress in alloy design concerning the type, morphology, and the volume fraction of the eutectic carbides. Samples were characterized by optical and Scanning electron microscopy.

  9. Solidification of the Sludge of a metal plating; La solidificacion de los lodos de la industria del laminado

    Energy Technology Data Exchange (ETDEWEB)

    Balkan, M.; Kocasoy, G.

    2000-07-01

    The sludge from metal plating industry is generally considered as hazardous waste due to its toxic heavy metal content. Solidification/stabilization techniques which are applied as prior to landfill gives good results for the disposal of especially inorganic sludges into the landfill in a safe manner. The research is aimed to investigate an effective and low cost solidification technique for the sludge of a metal plating factory by using different particles sizes of clinoptilolite. Clinoptilolite is a kind of natural zeolite and it was used in the research due to its good pozzolanic characteristic and its abundant reserves in Turkey. According to the results of the research, clinoptilolite was found as a successful solidification additive yielding products with high unconfined compressive strength and low leaching. (Author) 14 refs.

  10. Biogeochemical Investigations to Evaluate the Performance of the Waste Isolation Pilot Plant (WIPP) (Invited)

    Science.gov (United States)

    Gillow, J. B.

    2009-12-01

    The Waste Isolation Pilot Plant (WIPP) is a U.S. Department of Energy facility located in southeastern New Mexico, approximately 655 m (2150 ft.) below ground surface in a bedded salt, Permian evaporite formation. This mined geologic repository has been receiving transuranic (TRU) waste from defense-related and environmental-management activities since March 1999. TRU waste contains alpha-emitting transuranic nuclides with half-lives greater than twenty years at concentrations greater than 100 nCi/gram. These actinide-contaminated wastes were generated from nuclear-weapons production and related processing activities. They include various organics, adsorbed liquids, sludges, cellulosics, plastics, rubber, and a variety of metals and cemented materials. An extensive set of investigations were performed to establish the basis for TRU waste disposal at WIPP and to support initial certification from the U.S. Environmental Protection Agency. A significant element of the conceptual geochemical model for WIPP is the microbiologically-driven reactions leading to biodegradation of organic constituents in TRU wastes, as well as interactions with actinides present in the waste. This presentation will discuss the biogeochemical investigations that were performed to evaluate microbiological activity at WIPP, including studies of gas generation due to biodegradation of cellulose, plastic, and rubber materials and actinide-microbe interactions leading to changes in actinide chemical speciation. Highlights of this work are discussed here. Cellulose biodegradation in salt-brine systems results in the generation of carbon dioxide and hydrogen, and aqueous fermentation products (low molecular weight organic acids). Hypersaline brine can limit the range of microbial metabolic pathways, due to the energetic stresses of maintaining osmotic balance compatible with metabolic processes. Methanogenesis yields the lowest free energy per mole of carbon and as such is often not detected in

  11. Avaliação da técnica de solidificação/estabilização no tratamento de resíduo têxtil: produção de bloco cerâmico de vedação Evaluation of solidification/stabilization process in the treatment of textile wastes: production of ceramic blocks

    Directory of Open Access Journals (Sweden)

    F. M. S. Ramos

    2009-12-01

    through the solidification/stabilization (s/s process. Initially, the characterization of the textile waste and clay, used as matrices for the production of the ceramic blocks, was carried out. The chemical composition of textile waste varies and contains Al, Fe, Mn, Na, Pb, Cu, Zn and Cr, from the textile process and the treatment of sewage generated in the process. The waste was classified as a not-dangerous and not-inert residue. Afterwards, blocks with compositions 0, 5, 10, 15, 20 and 25% of textile waste were prepared. The mixture was made proportional with a percentage of dry mass. For comparative analysis of the chemical characteristics of these blocks incorporated with textile waste, were produced ceramic blocks only with clay. The experimental results indicated that concentrations of analyzed metals in both leached and solubilized extracts from ceramic blocks with incorporation of textile waste were below the limits set by a ABNT standard for solid residue. They can then be classified as non-hazardous and inert, offering no risk of future contamination of soil during their lifetime, as well as when disposed in landfill after their use. Experimental results related to the brick compressive strength showed that all the proportions of incorporation met the requirements an ABNT standard. Results also showed that, with up to 20% of textile waste added to the bricks, water absorption met the requirements of the ABNT standard. Thus, the s/s process was able to effectively immobilize the metals present in the textile waste into the ceramic blocks.

  12. Impact of Corrections to the Spallings Volume Calculation on Waste Isolation Pilot Plant Performance Assessment [Poster

    Energy Technology Data Exchange (ETDEWEB)

    Kicker, Dwayne Curtis; Herrick, Courtney G; Zeitler, Todd

    2016-01-01

    The numerical code DRSPALL (from direct release spallings) is written to calculate the volume of Waste Isolation Pilot Plant solid waste subject to material failure and transport to the surface (i.e., spallings) as a result of a hypothetical future inadvertent drilling intrusion into the repository. An error in the implementation of the DRSPALL finite difference equations was discovered and documented in a software problem report in accordance with the quality assurance procedure for software requirements. This paper describes the corrections to DRSPALL and documents the impact of the new spallings data from the modified DRSPALL on previous performance assessment calculations. Updated performance assessments result in more simulations with spallings, which generally translates to an increase in spallings releases to the accessible environment. Total normalized radionuclide releases using the modified DRSPALL data were determined by forming the summation of releases across each potential release pathway, namely borehole cuttings and cavings releases, spallings releases, direct brine releases, and transport releases. Because spallings releases are not a major contributor to the total releases, the updated performance assessment calculations of overall mean complementary cumulative distribution functions for total releases are virtually unchanged. Therefore, the corrections to the spallings volume calculation did not impact Waste Isolation Pilot Plant performance assessment calculation results.

  13. Impact of Corrections to the Spallings Volume Calculation on Waste Isolation Pilot Plant Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kicker, Dwayne Curtis [Stoller Newport News Nuclear, Inc., Carlsbad, NM (United States); Herrick, Courtney G [Sandia National Laboratories., Carlsbad, NM (United States); Zeitler, Todd [Sandia National Laboratories., Carlsbad, NM (United States)

    2015-11-01

    The numerical code DRSPALL (from direct release spallings) is written to calculate the volume of Waste Isolation Pilot Plant solid waste subject to material failure and transport to the surface (i.e., spallings) as a result of a hypothetical future inadvertent drilling intrusion into the repository. An error in the implementation of the DRSPALL finite difference equations was discovered and documented in a software problem report in accordance with the quality assurance procedure for software requirements. This paper describes the corrections to DRSPALL and documents the impact of the new spallings data from the modified DRSPALL on previous performance assessment calculations. Updated performance assessments result in more simulations with spallings, which generally translates to an increase in spallings releases to the accessible environment. Total normalized radionuclide releases using the modified DRSPALL data were determined by forming the summation of releases across each potential release pathway, namely borehole cuttings and cavings releases, spallings releases, direct brine releases, and transport releases. Because spallings releases are not a major contributor to the total releases, the updated performance assessment calculations of overall mean complementary cumulative distribution functions for total releases are virtually unchanged. Therefore, the corrections to the spallings volume calculation did not impact Waste Isolation Pilot Plant performance assessment calculation results.

  14. Performance Evaluation of Asphalt Modified with Municipal Wastes for Sustainable Pavement Construction

    Directory of Open Access Journals (Sweden)

    Muhammad Nasir Amin

    2016-09-01

    Full Text Available The severe hot temperature and high traffic loadings in the Kingdom of Saudi Arabia (KSA are causing distress in flexible pavements within a few years of service. Secondly, the conventional bitumen extracted from Saudi oil refineries have a performance grade of 64-10 (PG 64-10, which does not meet the SuperPave performance grade requirement for most of the KSA’s regions. In order to improve the performance grade of bitumen, different percentages of municipal wastes (plastic and crumb rubber were used as bitumen additives. The performance of bitumen at low, intermediate, and high temperatures was evaluated. This is important as the waste production is rising significantly due to the fast urbanization and high population growth in the KSA. Particularly, when there are very few ways of recycling these wastes (municipal, as well as industrial, which in fact have great impact on the environment. High-density polyethylene (HDP, low-density polyethylene (LDP, and crumb rubber (CR with 5%, 10%, and 15% by weight of bitumen, were mixed with the base bitumen (PG 64-10. Rotational viscometer (RV, dynamic shear rheometer (DSR, and bending beam rheometer (BBR were used to evaluate the viscosity, rutting, fatigue, and low-temperature behavior of base and modified binders. The test results indicated that the rutting (permanent deformation and fatigue resistance were significantly improved in modified binders due to the improvement in the visco-elastic properties.

  15. Performance Assessment of a Generic Repository in Bedded Salt for DOE-Managed Nuclear Waste

    Science.gov (United States)

    Stein, E. R.; Sevougian, S. D.; Hammond, G. E.; Frederick, J. M.; Mariner, P. E.

    2016-12-01

    A mined repository in salt is one of the concepts under consideration for disposal of DOE-managed defense-related spent nuclear fuel (SNF) and high level waste (HLW). Bedded salt is a favorable medium for disposal of nuclear waste due to its low permeability, high thermal conductivity, and ability to self-heal. Sandia's Generic Disposal System Analysis framework is used to assess the ability of a generic repository in bedded salt to isolate radionuclides from the biosphere. The performance assessment considers multiple waste types of varying thermal load and radionuclide inventory, the engineered barrier system comprising the waste packages, backfill, and emplacement drifts, and the natural barrier system formed by a bedded salt deposit and the overlying sedimentary sequence (including an aquifer). The model simulates disposal of nearly the entire inventory of DOE-managed, defense-related SNF (excluding Naval SNF) and HLW in a half-symmetry domain containing approximately 6 million grid cells. Grid refinement captures the detail of 25,200 individual waste packages in 180 disposal panels, associated access halls, and 4 shafts connecting the land surface to the repository. Equations describing coupled heat and fluid flow and reactive transport are solved numerically with PFLOTRAN, a massively parallel flow and transport code. Simulated processes include heat conduction and convection, waste package failure, waste form dissolution, radioactive decay and ingrowth, sorption, solubility limits, advection, dispersion, and diffusion. Simulations are run to 1 million years, and radionuclide concentrations are observed within an aquifer at a point approximately 4 kilometers downgradient of the repository. The software package DAKOTA is used to sample likely ranges of input parameters including waste form dissolution rates and properties of engineered and natural materials in order to quantify uncertainty in predicted concentrations and sensitivity to input parameters. Sandia

  16. Kinetic Phase Diagrams of Ternary Al-Cu-Li System during Rapid Solidification: A Phase-Field Study.

    Science.gov (United States)

    Yang, Xiong; Zhang, Lijun; Sobolev, Sergey; Du, Yong

    2018-02-08

    Kinetic phase diagrams in technical alloys at different solidification velocities during rapid solidification are of great importance for guiding the novel alloy preparation, but are usually absent due to extreme difficulty in performing experimental measurements. In this paper, a phase-field model with finite interface dissipation was employed to construct kinetic phase diagrams in the ternary Al-Cu-Li system for the first time. The time-elimination relaxation scheme was utilized. The solute trapping phenomenon during rapid solidification could be nicely described by the phase-field simulation, and the results obtained from the experiment measurement and/or the theoretical model were also well reproduced. Based on the predicted kinetic phase diagrams, it was found that with the increase of interface moving velocity and/or temperature, the gap between the liquidus and solidus gradually reduces, which illustrates the effect of solute trapping and tendency of diffusionless solidification.

  17. Dendritic Solidification in a Copper Nickel Alloy

    OpenAIRE

    DÜNDAR, Sacit

    2014-01-01

    The distribution of nickel in dendrite arms and in interdendritic regions of copper-10% nickel alloy solidified under production conditions designed to provide 4 different cooling rates was investigated. The results indicate that at different rates of solidification undercooling, diffusion and convection mechanisms affect the microsegregation of nickel and copper in the cast materials to various extents.

  18. Microstructure Development during Solidification of Aluminium Alloys

    NARCIS (Netherlands)

    Ruvalcaba Jimenez, D.G.

    2009-01-01

    This Thesis demonstrates studies on microstructure development during the solidification of aluminium alloys. New insights of structure development are presented here. Experimental techniques such as quenching and in-situ High-brilliance X-ray microscopy were utilized to study the microstructure

  19. Effect of Convection on the Isothermal Coupled Peritectic Solidification in the Single Crystal Superalloy

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Jiho; Sung, Changhoon; Lee, Jehyun [Changwon National University, Changwon (Korea, Republic of); Shin, Jongho [Doosan Heavy Industries and Construction Co. Ltd, Changwon (Korea, Republic of); Seo, Seongmoon [Korea Institute of Materials Science, Changwon (Korea, Republic of)

    2016-04-15

    The γ/γ´ two-phase growth commonly observed at γ interdendritic regions in Ni-base superalloys is known to be the eutectic microstructure. However, it is still unclear whether this is due to a eutectic or peritectic reaction. Directional solidification experiments of the Ni-base superalloy CMSX-10 were performed at low solidification rates in order to induce the coupled growth of γ/γ´ phases and to investigate their growth behavior. The γ and γ´ phases were found to grow simultaneously, maintaining an isothermal interface. Directional solidification experiments in a thin tube (0.8 mm ID) suggest that convection enhances the formation of two phase peritectic growth with a planar interface and the γ/γ´ might be the couped peritectic.

  20. Numerical modelling of solidification of thin walled hypereutectic ductile cast iron

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Hattel, Jesper; Tiedje, Niels

    2006-01-01

    Numerical simulation of solidification of ductile cast iron is normally based on a model where graphite nodules are surrounded by an austenite shell. The two phases are then growing as two concentric spheres governed by diffusion of carbon through the austenite shell. Experiments have however shown...... simulation of thin-walled ductile iron castings. Simulations have been performed with a 1-D numerical solidi¬fication model that includes the precipitation of non-eutectic austenite during the eutectic stage. Results from the simulations have been compared with experimental castings with wall thick...... solidification had only one main stage. The simulations reveal that the first stage of solidification can be explained by precipitation of off-eutectic austenite...

  1. Analysis of the effect of shrinkage on macrosegregation in alloy solidification

    Science.gov (United States)

    Krane, Matthew John M.; Incropera, Frank P.

    1995-09-01

    Numerical calculations based on a continuum model are used to examine the effects of solidification shrinkage on the redistribution of solute in a Pb-19.2 pct Sn mixture which is convectively cooled at a sidewall. For each of three different cooling rates, separate calculations are performed for shrinkage and buoyancy-induced flows, as well as for the combined influence of shrinkage and buoyancy effects. The calculations reveal that flow and macrosegregation patterns are more strongly influenced by buoyancy effects over a wide range of solidification rates. Although extremely large solidification rates yield small regions near the chilled wall in which shrinkage-induced flows control the redis-tribution of solute, the overall effect on macrosegregation is small relative to that associated with buoyancy. Scaling analysis of the governing equations produces reference shrinkage and buoyancy velocities which can be used to extend the current numerical results to other binary systems.

  2. A Probabilistic Performance Assessment Study of Potential Low-Level Radioactive Waste Disposal Sites in Taiwan

    Science.gov (United States)

    Knowlton, R. G.; Arnold, B. W.; Mattie, P. D.; Kuo, M.; Tien, N.

    2006-12-01

    For several years now, Taiwan has been engaged in a process to select a low-level radioactive waste (LLW) disposal site. Taiwan is generating LLW from operational and decommissioning wastes associated with nuclear power reactors, as well as research, industrial, and medical radioactive wastes. The preliminary selection process has narrowed the search to four potential candidate sites. These sites are to be evaluated in a performance assessment analysis to determine the likelihood of meeting the regulatory criteria for disposal. Sandia National Laboratories and Taiwan's Institute of Nuclear Energy Research have been working together to develop the necessary performance assessment methodology and associated computer models to perform these analyses. The methodology utilizes both deterministic (e.g., single run) and probabilistic (e.g., multiple statistical realizations) analyses to achieve the goals. The probabilistic approach provides a means of quantitatively evaluating uncertainty in the model predictions and a more robust basis for performing sensitivity analyses to better understand what is driving the dose predictions from the models. Two types of disposal configurations are under consideration: a shallow land burial concept and a cavern disposal concept. The shallow land burial option includes a protective cover to limit infiltration potential to the waste. Both conceptual designs call for the disposal of 55 gallon waste drums within concrete lined trenches or tunnels, and backfilled with grout. Waste emplaced in the drums may be solidified. Both types of sites are underlain or placed within saturated fractured bedrock material. These factors have influenced the conceptual model development of each site, as well as the selection of the models to employ for the performance assessment analyses. Several existing codes were integrated in order to facilitate a comprehensive performance assessment methodology to evaluate the potential disposal sites. First, a need

  3. The Department of Energy, Office of Environmental Restoration and Waste Management: Project performance study

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    The Office of Environmental Restoration and Waste Management (EM) of the US Department of Energy commissioned Independent Project Analysis, Inc. (IPA) to perform this Project Performance Study to provide a quantitative analysis determining how well EM develops and executes environmental remediation and waste management projects. The approach consisted of collecting detailed data on a sample of 65 completed and ongoing EM projects conducted since 1984. These data were then compared with key project characteristics and outcomes from 233 environmental remediation projects (excluding EM) in IPA`s Environmental Remediation Database and 951 projects In IPA`s Capital Projects Database. The study establishes the standing of the EM system relative to other organizations, and suggests areas and opportunities for improvement.

  4. Performance assessments insights on the use of cements in waste management

    Directory of Open Access Journals (Sweden)

    Snyder K.

    2011-04-01

    Full Text Available The use of cementitious materials has been proposed in a variety of waste management systems because these materials can have a variety of desirable performance characteristics: hydraulic isolation, chemical isolation, structural stability. Cementitious barriers are commonly engineered with a goal of achieving the highest quality material possible (e.g. minimizing hydraulic conductivity, porosity, tortuosity, diffusivity. However, a single performance goal may not be optimum when practical considerations of designs and performance characteristics are considered simultaneously. In addition, laboratory-scale optimized designs may have field-scale characteristics that are less than ideal.

  5. Waste Form Release Data Package for the 2005 Integrated Disposal Facility Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Eric M.; McGrail, B. Peter; Rodriguez, Elsa A.; Schaef, Herbert T.; Saripalli, Prasad; Serne, R. Jeffrey; Krupka, Kenneth M.; Martin, P. F.; Baum, Steven R.; Geiszler, Keith N.; Reed, Lunde R.; Shaw, Wendy J.

    2004-09-01

    This data package documents the experimentally derived input data on the representative waste glasses; LAWA44, LAWB45, and LAWC22. This data will be used for Subsurface Transport Over Reactive Multi-phases (STORM) simulations of the Integrated Disposal Facility (IDF) for immobilized low-activity waste (ILAW). The STORM code will be used to provide the near-field radionuclide release source term for a performance assessment to be issued in July 2005. Documented in this data package are data related to 1) kinetic rate law parameters for glass dissolution, 2) alkali (Na+)-hydrogen (H+) ion exchange rate, 3) chemical reaction network of secondary phases that form in accelerated weathering tests, and 4) thermodynamic equilibrium constants assigned to these secondary phases. The kinetic rate law and Na+-H+ ion exchange rate were determined from single-pass flow-through experiments. Pressurized unsaturated flow (PUF) and product consistency (PCT) tests where used for accelerated weathering or aging of the glasses in order to determine a chemical reaction network of secondary phases that form. The majority of the thermodynamic data used in this data package were extracted from the thermody-namic database package shipped with the geochemical code EQ3/6, version 8.0. Because of the expected importance of 129I release from secondary waste streams being sent to IDF from various thermal treatment processes, parameter estimates for diffusional release and solubility-controlled release from cementitious waste forms were estimated from the available literature.

  6. Diesel engine performance and emissions with fuels derived from waste tyres.

    Science.gov (United States)

    Verma, Puneet; Zare, Ali; Jafari, Mohammad; Bodisco, Timothy A; Rainey, Thomas; Ristovski, Zoran D; Brown, Richard J

    2018-02-06

    The disposal of waste rubber and scrap tyres is a significant issue globally; disposal into stockpiles and landfill poses a serious threat to the environment, in addition to creating ecological problems. Fuel production from tyre waste could form part of the solution to this global issue. Therefore, this paper studies the potential of fuels derived from waste tyres as alternatives to diesel. Production methods and the influence of reactor operating parameters (such as reactor temperature and catalyst type) on oil yield are outlined. These have a major effect on the performance and emission characteristics of diesel engines when using tyre derived fuels. In general, tyre derived fuels increase the brake specific fuel consumption and decrease the brake thermal efficiency. The majority of studies indicate that NOx emissions increase with waste tyre derived fuels; however, a few studies have reported the opposite trend. A similar increasing trend has been observed for CO and CO 2 emissions. Although most studies reported an increase in HC emission owing to lower cetane number and higher density, some studies have reported reduced HC emissions. It has been found that the higher aromatic content in such fuels can lead to increased particulate matter emissions.

  7. Fluidized bed steam reformed mineral waste form performance testing to support Hanford Supplemental Low Activity Waste Immobilization Technology Selection

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pierce, E. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Cozzi, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, C. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Daniel, W. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Herman, C. C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Miller, D. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Missimer, D. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, C. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Williams, M. F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Brown, C. F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, N. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Neeway, J. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Valenta, M. M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gill, G. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Swanberg, D. J. [Washington River Protection Solutions (WRPS), Richland, WA (United States); Robbins, R. A. [Washington River Protection Solutions (WRPS), Richland, WA (United States); Thompson, L. E. [Washington River Protection Solutions (WRPS), Richland, WA (United States)

    2015-10-01

    This report describes the benchscale testing with simulant and radioactive Hanford Tank Blends, mineral product characterization and testing, and monolith testing and characterization. These projects were funded by DOE EM-31 Technology Development & Deployment (TDD) Program Technical Task Plan WP-5.2.1-2010-001 and are entitled “Fluidized Bed Steam Reformer Low-Level Waste Form Qualification”, Inter-Entity Work Order (IEWO) M0SRV00054 with Washington River Protection Solutions (WRPS) entitled “Fluidized Bed Steam Reforming Treatability Studies Using Savannah River Site (SRS) Low Activity Waste and Hanford Low Activity Waste Tank Samples”, and IEWO M0SRV00080, “Fluidized Bed Steam Reforming Waste Form Qualification Testing Using SRS Low Activity Waste and Hanford Low Activity Waste Tank Samples”. This was a multi-organizational program that included Savannah River National Laboratory (SRNL), THOR® Treatment Technologies (TTT), Pacific Northwest National Laboratory (PNNL), Oak Ridge National Laboratory (ORNL), Office of River Protection (ORP), and Washington River Protection Solutions (WRPS). The SRNL testing of the non-radioactive pilot-scale Fluidized Bed Steam Reformer (FBSR) products made by TTT, subsequent SRNL monolith formulation and testing and studies of these products, and SRNL Waste Treatment Plant Secondary Waste (WTP-SW) radioactive campaign were funded by DOE Advanced Remediation Technologies (ART) Phase 2 Project in connection with a Work-For-Others (WFO) between SRNL and TTT.

  8. Near-Field Hydrology Data Package for the Immobilized Low-Activity Waste 2001 Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    PD Meyer; RJ Serne

    1999-12-21

    Lockheed Martin Hanford Company (LMHC) is designing and assessing the performance of disposal facilities to receive radioactive wastes that are currently stored in single- and double-shell tanks at the Hanford Site. The preferred method for disposing of the portion that is classified as immobilized low-activity waste (ILAW) is to vitrify the waste and place the product in new-surface, shallow land burial facilities. The LMHC project to assess the performance of these disposal facilities is the Hanford ILAW Performance Assessment (PA) Activity. The goal of this project is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface water resources, and inadvertent intruders. Achieving this goal will require prediction of contaminant migration from the facilities. This migration is expected to occur primarily via the movement of water through the facilities and the consequent transport of dissolved contaminants in the pore water of the vadose zone. Pacific Northwest National Laboratory (PNNL) assists LMHC in its performance assessment activities. One of PNNL's tasks is to provide estimates of the physical, hydraulic, and transport properties of the materials comprising the disposal facilities and the disturbed region around them. These materials are referred to as the near-field materials. Their properties are expressed as parameters of constitutive models used in simulations of subsurface flow and transport. In addition to the best-estimate parameter values, information on uncertainty in the parameter values and estimates of the changes in parameter values over time are required to complete the PA. These parameter estimates and information are contained in this report, the Near-Field Hydrology Data Package.

  9. Performance analysis for waste repositories in the nordic countries. Report for project AFA-1.2

    Energy Technology Data Exchange (ETDEWEB)

    Vuori, S. [VTT Energy (Finland); Broden, K. [Studsvik RadWaste AB (Sweden); Carugati, S.; Brodersen, K. [Forskningscenter Risoe (Denmark); Walderhaug, T. [Icelandic Radiation Protection Institute (Iceland); Helgason, J. [Ekra Geological Consulting (Iceland); Sneve, M.; Hornkjoel, S. [Norwegian Radiation Protection (Norway); Backe, S. [IFE (Norway)

    1997-02-01

    The Nordic Nuclear Safety Research (NKS) project (AFA-1) focused on safety in the final disposal of long-lived low and medium level radioactive waste and its sub project (AFA-1.2), where this report has been produced, is dealing with the performance analysis of the engineered barrier system (near-field) of the repositories for low-and medium level wastes. The topic intentionally excludes the discussion of the characteristics of the geological host medium. Therefore a more generic discussion of the features of performance analysis is possible independent of the fact that different host media are considered in the Nordic countries. The different waste management systems existing and planned in the Nordic countries are shortly described in the report. In the report main emphasis is paid on the general repositories. Some of the phenomena and interactions relevant for a generic type of repository are discussed as well. Among the different approaches for the development of scenarios for safety and performance analyses one particular method - the Rock Engineering System (RES) - was chosen to be demonstratively tested in a brainstorming session, where the possible interactions and their safety significance were discussed employing a simplified and generic Nordic repository system as the reference system. As an overall impression, the AFA-project group concludes that the use of the RES approach is very easy to learn even during a short discussion session. The use of different ways to indicate the safety significance of various interactions in a graphical user interface increases the clarity. Within the project a simple software application was developed employing a generally available spread sheet programme. The developed tool allows an easy opportunity to link the cell specific comments readily available for the `reader` of the obtained results. A short review of the performance analyses carried out in the Nordic countries for actual projects concerning repositories for

  10. Performance Analysis of Organic Rankine-vapor Compression Ice Maker Utilizing Food Industry Waste Heat

    OpenAIRE

    Bing Hu; Yuanshu Cao; Weibin Ma

    2015-01-01

    To develop the organic Rankine-vapor compression ice maker driven by food industry exhaust gases and engine cooling water, an organic Rankine-vapor compression cycle system was employed for ice making and a thermodynamic model was developed and the effects of working fluid types, hot water temperature and condensation temperature on the system performance were analyzed and the ice making capacity from unit mass hot water and unit power waste heat were evaluated. The calculated results show th...

  11. Immobilization of fission products in phosphate ceramic waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Singh, D. [Argonne National Lab., IL (United States)

    1996-10-01

    The goal of this project is to develop and demonstrate the feasibility of a novel low-temperature solidification/stabilization (S/S) technology for immobilizing waste streams containing fission products such as cesium, strontium, and technetium in a chemically bonded phosphate ceramic. This technology can immobilize partitioned tank wastes and decontaminate waste streams containing volatile fission products.

  12. Mixing Performance of a Suspended Stirrer for Homogenizing Biodegradable Food Waste from Eatery Centers

    Directory of Open Access Journals (Sweden)

    Olumide Babarinsa

    2014-08-01

    Full Text Available Numerical simulation of a suspended stirrer within a homogenizing system is performed towards determining the mixing performance of a homogenizer. A two-dimensional finite volume formulation is developed for the cylindrical system that is used for the storage and stirring of biodegradable food waste from eatery centers. The numerical solver incorporates an analysis of the property distribution for viscous food waste in a storage tank, while coupling the impact of mixing on the slurry fluid. Partial differential equations, which describe the conservation of mass, momentum and energy, are applied. The simulation covers the mixing and heating cycles of the slurry. Using carrot-orange soup as the operating fluid (and its thermofluid properties and assuming constant density and temperature-dependent viscosity, the velocity and temperature field distribution under the influence of the mixing source term are analyzed. A parametric assessment of the velocity and temperature fields is performed, and the results are expected to play a significant role in designing a homogenizer for biodegradable food waste.

  13. Technology for safe treatment of radioisotope organic wastes

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Jin; Park, Chong Mook; Choi, W. K.; Lee, K. W.; Moon, J. K.; Yang, H. Y.; Kim, B. T.; Park, S. C

    1999-12-01

    An examination of chemical and radiological characteristics of RI organic liquid waste, wet oxidation by Fenton reaction and decomposition liquid waste treatment process were studied. These items will be applied to develop the equipment of wet oxidation and decomposition liquid waste treatment mixed processes for the safe treatment of RI organic liquid waste which is consisted of organic solvents such as toluene, alcohol and acetone. Two types of toluene solutions were selected as a candidate decomposition material. As for the first type, the concentration of toluene was above 20 vol percent. As for the second type, the solubility of toluene was considered. The decomposition ration by Fenton reaction was above 95 percent for both of them. From the adsorption equilibrium tests, a -Na{sup +} substituted/acid treated activated carbon and Zeocarbon mixed adsorbent was selected for the fixed adsorption column. This mixed adsorbent will be used to obtain the basic design data of liquid waste purification equipment for the treatment of decomposition liquid waste arising from the wet oxidation process. Solidification and degree of strength tests were performed with the simulated sludge/spent adsorbent of MgO as an oxide type and KH{sub 2}PO{sub 4}. From the test results, the design and fabrication of wet oxidation and liquid waste purification process equipment was made, and a performance test was carried out. (author)

  14. E-waste : Collect more, treat better; Tracking take-back system performance for eco-efficient electronics recycling

    NARCIS (Netherlands)

    Wang, F.

    2014-01-01

    This dissertation establishes a methodology for evaluating the performance of take-back and treatment systems for end-oflife electronics (e-waste). First, a comprehensive classification is developed to fully understand the complex characteristics of e-waste. A multivariate model is then created to

  15. 40 CFR 60.1025 - Do subpart E new source performance standards also apply to my municipal waste combustion unit?

    Science.gov (United States)

    2010-07-01

    ... subpart E of this part does not apply to your municipal waste combustion unit. ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Do subpart E new source performance standards also apply to my municipal waste combustion unit? 60.1025 Section 60.1025 Protection of...

  16. Proceedings of the tenth annual DOE low-level waste management conference: Session 2: Site performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    1988-12-01

    This document contains twelve papers on various aspects of low-level radioactive waste management. Topics of this volume include: performance assessment methodology; remedial action alternatives; site selection and site characterization procedures; intruder scenarios; sensitivity analysis procedures; mathematical models for mixed waste environmental transport; and risk assessment methodology. Individual papers were processed separately for the database. (TEM)

  17. Incorporation of fragmentation into a volume average solidification model

    Science.gov (United States)

    Zheng, Y.; Wu, M.; Kharicha, A.; Ludwig, A.

    2018-01-01

    In this study, a volume average solidification model was extended to consider fragmentation as a source of equiaxed crystals during mixed columnar-equiaxed solidification. The formulation suggested for fragmentation is based on two hypotheses: the solute-driven remelting is the dominant mechanism; and the transport of solute-enriched melt through an interdendritic flow in the columnar growth direction is favorable for solute-driven remelting and is the necessary condition for fragment transportation. Furthermore, a test case with Sn-10 wt%Pb melt solidifying vertically downward in a 2D domain (50 × 60 mm2) was calculated to demonstrate the model’s features. Solidification started from the top boundary, and a columnar structure developed initially with its tip growing downward. Furthermore, thermo-solutal convection led to fragmentation in the mushy zone near the columnar tip front. The fragments transported out of the columnar region continued to grow and sink, and finally settled down and piled up in the bottom domain. The growing columnar structure from the top and pile-up of equiaxed crystals from the bottom finally led to a mixed columnar-equiaxed structure, in turn leading to a columnar-to-equiaxed transition (CET). A special macrosegregation pattern was also predicted, in which negative segregation occurred in both columnar and equiaxed regions and a relatively strong positive segregation occurred in the middle domain near the CET line. A parameter study was performed to verify the model capability, and the uncertainty of the model assumption and parameter was discussed.

  18. Performance management system as a tool for promoting effective waste control : the case of Emfuleni Local Municipality / Sipho J. Ngwenya

    OpenAIRE

    Ngwenya, Sipho Jeffrey

    2014-01-01

    This study aimed at evaluating the degree to which Performance Management System is being executed at Waste Management Unit within the Emfuleni Local Municipality hence the topic “Performance Management System as a tool for promoting effective waste control: The case of the Emfuleni Local Municipality.” The Performance Management System issues a structure for establishing development needs, determining suitable resources, and making the recommendations regarding suitable PMS of which managers...

  19. NWTS program criteria for mined geologic disposal of nuclear waste: repository performance and development criteria. Public draft

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-07-01

    This document, DOE/NWTS-33(3) is one of a series of documents to establish the National Waste Terminal Storage (NWTS) program criteria for mined geologic disposal of high-level radioactive waste. For both repository performance and repository development it delineates the criteria for design performance, radiological safety, mining safety, long-term containment and isolation, operations, and decommissioning. The US Department of Energy will use these criteria to guide the development of repositories to assist in achieving performance and will reevaluate their use when the US Nuclear Regulatory Commission issues radioactive waste repository rules.

  20. Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) verification and validation plan. version 1.

    Energy Technology Data Exchange (ETDEWEB)

    Bartlett, Roscoe Ainsworth; Arguello, Jose Guadalupe, Jr.; Urbina, Angel; Bouchard, Julie F.; Edwards, Harold Carter; Freeze, Geoffrey A.; Knupp, Patrick Michael; Wang, Yifeng; Schultz, Peter Andrew; Howard, Robert (Oak Ridge National Laboratory, Oak Ridge, TN); McCornack, Marjorie Turner

    2011-01-01

    The objective of the U.S. Department of Energy Office of Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) is to provide an integrated suite of computational modeling and simulation (M&S) capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive-waste storage facility or disposal repository. To meet this objective, NEAMS Waste IPSC M&S capabilities will be applied to challenging spatial domains, temporal domains, multiphysics couplings, and multiscale couplings. A strategic verification and validation (V&V) goal is to establish evidence-based metrics for the level of confidence in M&S codes and capabilities. Because it is economically impractical to apply the maximum V&V rigor to each and every M&S capability, M&S capabilities will be ranked for their impact on the performance assessments of various components of the repository systems. Those M&S capabilities with greater impact will require a greater level of confidence and a correspondingly greater investment in V&V. This report includes five major components: (1) a background summary of the NEAMS Waste IPSC to emphasize M&S challenges; (2) the conceptual foundation for verification, validation, and confidence assessment of NEAMS Waste IPSC M&S capabilities; (3) specifications for the planned verification, validation, and confidence-assessment practices; (4) specifications for the planned evidence information management system; and (5) a path forward for the incremental implementation of this V&V plan.

  1. FY16 Annual Accomplishments - Waste Form Development and Performance: Evaluation Of Ceramic Waste Forms - Comparison Of Hot Isostatic Pressed And Melt Processed Fabrication Methods

    Energy Technology Data Exchange (ETDEWEB)

    Amoroso, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dandeneau, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-10-13

    FY16 efforts were focused on direct comparison of multi-phase ceramic waste forms produced via melt processing and HIP methods. Based on promising waste form compositions previously devised at SRNL, simulant material was prepared at SRNL and a portion was sent to the Australian Nuclear Science and Technology Organization (ANSTO) for HIP treatments, while the remainder of the material was melt processed at SRNL. The microstructure, phase formation, elemental speciation, and leach behavior, and radiation stability of the fabricated ceramics was performed. In addition, melt-processed ceramics designed with different fractions of hollandite, zirconolite, perovskite, and pyrochlore phases were investigated. for performance and properties.

  2. Municipal household solid waste collection strategies in an African megacity: analysis of public private partnership performance in Lagos.

    Science.gov (United States)

    Aliu, Ibrahim Rotimi; Adeyemi, Oluwagbemiga Ezekiel; Adebayo, Adeolu

    2014-09-01

    Managing municipal solid waste is a pervasive urban problem globally. While several strategies have been applied for efficient municipal solid waste management in developing economies, their performance level has not been critically investigated. Among these strategies, the public private partnership has widest appeal. This study examines the performance of public private partnership in household solid waste collection in Lagos, Nigeria. We collected primary data using a municipal solid waste survey in three residential density areas of Lagos megacity. Descriptive and inferential statistics were used to analyse the data. Two indexes of service performance, namely the service reliability index and operational quality index, were created to produce evidence on public private partnership performance in municipal solid waste collection in Lagos. Results show that the average amount of household solid waste generation per week ranges between 22.75 kg in the medium residential density area and 30.39 kg in the high residential density region of the city. The estimated per capita waste generated in Lagos Megacity is 0.95 kg day(-1). Regression models indicate that the public private partnership performance is significantly influenced by economic status, affordability, flexibility, consistency, cleanliness, coverage and accessibility, as well as number of waste collection vehicles, vehicle maintenance, capacity, trip rate, frequency, number of personnel and quality of personnel. Findings from this study reveal that Lagos residents have strong positive perception of public private partnership as a waste collection policy framework. The study has important policy and practical implications for urban waste management, public health and sustainability in developing economies. © The Author(s) 2014.

  3. Utilization of fly ash for stabilization/solidification of heavy metal contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Dermatas, D.; Meng, X. [Stevens Inst. of Technology, Hoboken, NJ (United States)

    1995-12-01

    Pozzolanic-based stabilization/solidification (S/S) is an effective, yet economic technological alternative to immobilize heavy metals in contaminated soils and sludges. Fly ash waste materials were used along with quicklime (CaO) to immobilize lead, trivalent and hexavalent chromium present in contaminated clayey sand soils. The degree of heavy metal immobilization was evaluated using the Toxicity Characteristic Leaching Procedure (TCLP) as well as controlled extraction experiments. These leaching test results along with X-ray diffraction (XRD), scanning electron microscope and energy dispersive x-ray (SEM-EDX) analyses were also implemented to elucidate the mechanisms responsible for immobilization of the heavy metals under study. Finally, the reusability of the stabilized waste forms in construction applications was also investigated by performing unconfined compressive strength and swell tests. Results suggest that the controlling mechanism for both lead and hexavalent chromium immobilization is surface adsorption, whereas for trivalent chromium it is hydroxide precipitation. Addition of fly ash to the contaminated soils effectively reduced heavy metal leachability well below the non-hazardous regulatory limits. However, quicklime addition was necessary in order to attain satisfactory immobilization levels. Overall, fly ash addition increases the immobilization pH region for all heavy metals tested, and significantly improves the stress-strain properties of the treated solids, thus allowing their reuse as readily available construction materials. The only potential problem associated with this quicklime/fly ash treatment is the excessive formation of the pozzolanic product ettringite in the presence of sulfates. Ettringite, when brought in contact with water, may cause significant swelling and subsequent deterioration of the stabilized matrix. Addition of minimum amounts of barium hydroxide was shown to effectively eliminate ettringite formation.

  4. Numerical Model for Solidification Zones Selection in the Large Ingots

    Directory of Open Access Journals (Sweden)

    Wołczyński W.

    2015-12-01

    Full Text Available A vertical cut at the mid-depth of the 15-ton forging steel ingot has been performed by curtesy of the CELSA - Huta Ostrowiec plant. Some metallographic studies were able to reveal not only the chilled undersized grains under the ingot surface but columnar grains and large equiaxed grains as well. Additionally, the structural zone within which the competition between columnar and equiaxed structure formation was confirmed by metallography study, was also revealed. Therefore, it seemed justified to reproduce some of the observed structural zones by means of numerical calculation of the temperature field. The formation of the chilled grains zone is the result of unconstrained rapid solidification and was not subject of simulation. Contrary to the equiaxed structure formation, the columnar structure or columnar branched structure formation occurs under steep thermal gradient. Thus, the performed simulation is able to separate both discussed structural zones and indicate their localization along the ingot radius as well as their appearance in term of solidification time.

  5. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Volume 2, Technical basis

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    Before disposing of transuranic radioactive waste in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments (PAs) of the WIPP for the DOE to provide interim guidance while preparing for a final compliance evaluation. This volume, Volume 2, contains the technical basis for the 1992 PA. Specifically, it describes the conceptual basis for consequence modeling and the PA methodology, including the selection of scenarios for analysis, the determination of scenario probabilities, and the estimation of scenario consequences using a Monte Carlo technique and a linked system of computational models. Additional information about the 1992 PA is provided in other volumes. Volume I contains an overview of WIPP PA and results of a preliminary comparison with the long-term requirements of the EPA`s Environmental Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). Volume 3 contains the reference data base and values for input parameters used in consequence and probability modeling. Volume 4 contains uncertainty and sensitivity analyses related to the preliminary comparison with 40 CFR 191B. Volume 5 contains uncertainty and sensitivity analyses of gas and brine migration for undisturbed performance. Finally, guidance derived from the entire 1992 PA is presented in Volume 6.

  6. Impact of Waste Materials and Organic Amendments on Soil Properties and Vegetative Performance

    Directory of Open Access Journals (Sweden)

    Steven L. McGeehan

    2012-01-01

    Full Text Available Waste materials, and materials derived from wastes, possess many characteristics that can improve soil fertility and enhance crop performance. These materials can be particularly useful as amendments to severely degraded soils associated with mining activities. This study evaluated biosolids, composts, log yard wastes, and two organic soil treatments for improved soil fertility and vegetative performance using side-by-side comparisons. Each plot was seeded with a standardized seed mix and evaluated for a series of soil chemical and physical parameters, total vegetation response, species diversity, ecological plant response, and invasion indices. All treatments were successful at improving soil fertility and promoting a self-sustaining vegetative cover. The level of available nitrogen had a strong impact on vegetative coverage, species distribution, and extent of unseeded vegetation. For example, high nitrogen treatments promoted a grass-dominated (low forb plant community with a low content of unseeded vegetation. In contrast, low nitrogen treatments promoted a more balanced plant community with a mixture of grass and forb species and greater susceptibility to unseeded vegetation establishment.

  7. Performance Assessment in Support of the 1996 Compliance Certification Application for the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D.R.; Basabilvazo, G.; Helton, J.C.; Jow, H.-N.; Marietta, M.G.

    1998-10-14

    The conceptual and computational structure of a performance assessment (PA) for the Waste Isolation Pilot Plant (WIPP) is described. Important parts of thk structure are @ maintenance of a separation between stochastic (i.e., aleatory) and subjective (i.e., epistemic) uncertain, with stochastic uncefinty arising from the many possible disruptions that could occur over the 10,000 Y regulatory period fiat applies to the WIPP and subjective uncertainty arising from `the imprecision with which many of the quantities rquired in tie `hdysis are known, (ii) use of Latin hypercttbe sampling to incorporate the effects of subjective uncefirtty, (iii) use of Monte Carlo (i.e., random) sampling to incorporate the effects of stochastic uncetinty, and OV) efficient use of tie necessarily limited number of mechanistic calculations that can be performed to SUPPOII the analysis. The WIPP is under development by the U.S. Department of Ener~ (DOE) for the geologic (i.e., deep underground) disposal of transuranic (TRU) waste, with the indicated PA supporting a ~Compliance Certification Application (CCA) by the DOE to the U.S. Environmental Protection Agency (EPA) in October 1996 for tie necessary certifications for the WIPP to begin operation. If certified, the WIPP will be the first operational faciliv in tie United States for the geologic disposal of ra&oactive waste.

  8. Sandia solidification process: consolidation and characterization. Part I. Consolidation studies

    Energy Technology Data Exchange (ETDEWEB)

    Johnstone, J.K.

    1978-05-01

    The consolidation behavior of a complex polycrystalline ceramic nuclear waste form composed of titanates, zeolite, and metallic silicon was studied. Initial solidification takes place by an ion exchange process. The resulting powder exhibits a large surface area, approximately 350 m/sup 2//g, and several decomposition, crystallization and phase change reactions from room temperature to 1100/sup 0/C. In spite of the large surface area, consolidation by cold pressing and atmospheric sintering to 1100/sup 0/C was not satisfactory. Vacuum hot pressing was found to produce fully dense pellets (less than 1% residual porosity) under very mild conditions, 6.9 MPa (1100 psi) and 1100/sup 0/C. The dominant densification mechanism was viscous flow. Under less than optimum hot pressing conditions, three stages of densification were observed. Initial densification took place by particle rearrangement which was described with a viscous flow model. Second stage densification occurred by a solution-precipitation process controlled by a phase boundary dissolution reaction. In several cases, a third, final densification stage was observed. Detailed studies describe the effects of heating rate, processing temperature, pressure, residence time, atmosphere, composition, heat treatment, and the addition of consolidation aids on the densification behavior. In addition, fully radioactive high level mixed fission product titanate/waste pellets (1.27 cm diameter) were hot pressed at Oak Ridge National Laboratory to demonstrate the feasibility of such a process in a remotely operated hot cell. High density uniform pellets were obtained.

  9. CFD analysis of sludge accumulation and hydraulic performance of a waste stabilization pond.

    Science.gov (United States)

    Alvarado, Andres; Sanchez, Esteban; Durazno, Galo; Vesvikar, Mehul; Nopens, Ingmar

    2012-01-01

    Sludge management in waste stabilization ponds (WSPs) is essential for safeguarding the system performance. Sludge accumulation patterns in WSPs are strongly influenced by the pond hydrodynamics. CFD modeling was applied to study the relation between velocity profiles and sludge deposition during 10 years of operation of the Ucubamba WSP in Cuenca (Ecuador). One tracer experiment was performed and three sludge accumulation scenarios based on bathymetric surveys were simulated. A residence time distribution (RTD) analysis illustrated the decrease of residence times due to sludge deposition. Sludge accumulation rates were calculated. The influence of flow pattern on the sludge deposition was studied, enabling better planning of future pond operation and desludging.

  10. Production of biodiesel by enzymatic transesterification of waste sardine oil and evaluation of its engine performance

    Directory of Open Access Journals (Sweden)

    A. Arumugam

    2017-12-01

    Full Text Available Waste sardine oil, a byproduct of fish industry, was employed as a low cost feedstock for biodiesel production. It has relatively high free fatty acid (FFA content (32 mg KOH/g of oil. Lipase enzyme immobilized on activated carbon was used as the catalyst for the transesterification reaction. Process variables viz. reaction temperature, water content and oil to methanol molar ratio were optimized. Optimum methanol to oil molar ratio, water content and temperature were found to be 9:1, 10 v/v% and 30 °C respectively. Reusability of immobilized lipase was studied and it was found after 5 cycles of reuse there was about 13% drop in FAME yield. Engine performance of the produced biodiesel was studied in a Variable Compression Engine and the results confirm that waste sardine oil is a potential alternate and low-cost feedstock for biodiesel production.

  11. Selection of a computer code for Hanford low-level waste engineered-system performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    McGrail, B.P.; Mahoney, L.A.

    1995-10-01

    Planned performance assessments for the proposed disposal of low-level waste (LLW) glass produced from remediation of wastes stored in underground tanks at Hanford, Washington will require calculations of radionuclide release rates from the subsurface disposal facility. These calculations will be done with the aid of computer codes. Currently available computer codes were ranked in terms of the feature sets implemented in the code that match a set of physical, chemical, numerical, and functional capabilities needed to assess release rates from the engineered system. The needed capabilities were identified from an analysis of the important physical and chemical process expected to affect LLW glass corrosion and the mobility of radionuclides. The highest ranked computer code was found to be the ARES-CT code developed at PNL for the US Department of Energy for evaluation of and land disposal sites.

  12. Performance of Spent Mushroom Farming Waste (SMFW) Activated Carbon for Ni (II) Removal

    Science.gov (United States)

    Desa, N. S. Md; Ghani, Z. Ab; Talib, S. Abdul; Tay, C. C.

    2016-07-01

    The feasibility of a low cost agricultural waste of spent mushroom farming waste (SMFW) activated carbon for Ni(II) removal was investigated. The batch adsorption experiments of adsorbent dosage, pH, contact time, metal concentration, and temperature were determined. The samples were shaken at 125 rpm, filtered and analyzed using ICP-OES. The fifty percent of Ni(II) removal was obtained at 0.63 g of adsorbent dosage, pH 5-6 (unadjusted), 60 min contact time, 50 mg/L Ni(II) concentration and 25 °C temperature. The evaluated SMFW activated carbon showed the highest performance on Ni(II) removal compared to commercial Amberlite IRC86 resin and zeolite NK3. The result indicated that SMFW activated carbon is a high potential cation exchange adsorbent and suitable for adsorption process for metal removal. The obtained results contribute toward application of developed SMFW activated carbon in industrial pilot study.

  13. Value-based performance measures for Hanford Tank Waste Remedition System (TWRS) Program

    Energy Technology Data Exchange (ETDEWEB)

    Keeney, R.L.; von Winterfeldt, D.

    1996-01-01

    The Tank Waste Remediation Systems (TWRS) Program is responsible for the safe storage, retrieval, treatment, and preparation for disposal of high-level waste currently stored in underground storage tanks at the Hanford site in Richland. The TWRS program has adopted a logical approach to decision making that is based on systems engineering and decision analysis (Westinghouse Hanford Company, 1995). This approach involves the explicit consideration of stakeholder values and an evaluation of the TWRS alternatives in terms of these values. Such evaluations need to be consistent across decisions. Thus, an effort was undertaken to develop a consistent, quantifiable set of measures that can be used by TVVRS to assess alternatives against the stakeholder values. The measures developed also met two additional requirements: 1) the number of measure should be relatively small; and 2) performance with respect to the measures should be relatively easy to estimate.

  14. Nuclear waste management. Quarterly progress report, July-September 1980

    Energy Technology Data Exchange (ETDEWEB)

    Chikalla, T.D.

    1980-11-01

    Research is reported on: high-level waste immobilization, alternative waste forms, TRU waste immobilization and decontamination, krypton solidification, thermal outgassing, /sup 129/I fixation, unsaturated zone transport, well-logging instrumentation, waste management system and safety studies, effectiveness of geologic isolation systems, waste/rock interactions, engineered barriers, backfill material, spent fuel storage (criticality), barrier sealing and liners for U mill tailings, and revegetation of inactive U tailings sites. (DLC)

  15. Approaches to consider covers and liners in a low-level waste disposal facility performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Seitz, Roger [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Phifer, Mark [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Suttora, Linda [USDOE, Office of Environmental Management, Germantown, MD (United States)

    2015-03-17

    On-site disposal cells are in use and being considered at several USDOE sites as the final disposition for large amounts of waste associated with cleanup of contaminated areas and facilities. These disposal cells are typically regulated by States and/or the USEPA in addition to having to comply with requirements in DOE Order 435.1, Radioactive Waste Management. The USDOE-EM Office of Site Restoration formed a working group to foster improved communication and sharing of information for personnel associated with these Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) disposal cells and work towards more consistent assumptions, as appropriate, for technical and policy considerations related to performance and risk assessments in support of a Record of Decision and Disposal Authorization Statement. One task completed by the working group addressed approaches for considering the performance of covers and liners/leachate collection systems in the context of a performance assessment (PA). A document has been prepared which provides recommendations for a general approach to address covers and liners/leachate collection systems in a PA and how to integrate assessments with defense-in-depth considerations such as design, operations and waste acceptance criteria to address uncertainties. Specific information and references are provided for details needed to address the evolution of individual components of cover and liner/leachate collection systems. This information is then synthesized into recommendations for best practices for cover and liner system design and examples of approaches to address the performance of covers and liners as part of a performance assessment of the disposal system.

  16. Probabilistic performance-assessment modeling of the mixed waste landfill at Sandia National Laboratories.

    Energy Technology Data Exchange (ETDEWEB)

    Peace, Gerald (Jerry) L. (.); Goering, Timothy James (GRAM, Inc.); Miller, Mark Laverne; Ho, Clifford Kuofei

    2007-01-01

    A probabilistic performance assessment has been conducted to evaluate the fate and transport of radionuclides (americium-241, cesium-137, cobalt-60, plutonium-238, plutonium-239, radium-226, radon-222, strontium-90, thorium-232, tritium, uranium-238), heavy metals (lead and cadmium), and volatile organic compounds (VOCs) at the Mixed Waste Landfill (MWL). Probabilistic analyses were performed to quantify uncertainties inherent in the system and models for a 1,000-year period, and sensitivity analyses were performed to identify parameters and processes that were most important to the simulated performance metrics. Comparisons between simulated results and measured values at the MWL were made to gain confidence in the models and perform calibrations when data were available. In addition, long-term monitoring requirements and triggers were recommended based on the results of the quantified uncertainty and sensitivity analyses.

  17. Effect of Organic Waste Concentration on Reactor Performance in Anaerobic Co-Fermentation of Wastewater of Tofu Industry and Organic Solid Waste

    Directory of Open Access Journals (Sweden)

    Sofyan Sofyan

    2015-06-01

    Full Text Available Fuel crisis of oil and gas that are faced currently requires a thought to look for an alternative energy. The objective of this study was to observe the effect of organic waste addition on reactor performance and to increase the production of biogas as an alternative renewable energy. The wastewater used was the wastewater from agglomeration of soy pulp in tofu industry, while the solid waste used was a mixture of organic waste from household and market waste. The study was conducted by fermenting the wastewater and organic waste together with sample volume 300 ml. The reactors were operated semi-continuously with substrate feeding every two weeks. The treatment used in this study were mass comparison of organic waste and wastewater (0:100%; (5:95%; (10:90%; (20:80%; (30:70%; and (40:60%. The results showed that the addition of organic waste affected the reactor performance and the amount of biogas produced. Anaerobic co-fermentation of wastewater from tofu industry and organic waste produced biogas more than fermentation of wastewater without organic waste. The highest amount of biogas was obtained in the treatment of organic waste addition as much as 30% with average volume of biogas was 728 ml in steady state condition.ABSTRAKKrisis bahan bakar minyak dan gas yang dihadapi saat ini memerlukan pemikiran untuk mencari energi alternatif. Penelitian ini bertujuan untuk mengamati pengaruh penambahan sampah organik terhadap kinerja reaktor anaerobik dan meningkatkan produksi biogas sebagai salah satu energi alternatif terbarukan. Limbah cair yang digunakan adalah limbah cair dari penggumpalan bubur kedelai pada industri tahu, sedangkan sampah organik yang digunakan adalah gabungan sampah organik dari rumah tangga dan sampah pasar. Penelitian dilakukan dengan mendigestasi limbah cair industri tahu dan sampah organik secara bersama-sama dalam reaktor anaerobik dengan volume sampel 300 ml. Reaktor dioperasikan secara semi kontinyu dengan pengumpanan

  18. Nuclear waste management. Quarterly progress report, April-June 1979

    Energy Technology Data Exchange (ETDEWEB)

    Platt, A.M.; Powell, J.A. (comps.)

    1979-09-01

    Progress is reported on: decontamination and densification of chop-leach cladding residues; monitoring methods for particulate and gaseous effluents from waste solidification process; TRU waste immobilization; krypton solidification; /sup 14/C and /sup 129/I fixation; waste management system and safety studies; waste isolation safety assessment; well logging instrumentation development for shallow land burial; monitoring and physical characterization of unsaturated zone transport; detection and characterization of mobile organic complexes of fission products; and electropolishing for surface decontamination of metals. 9 figures, 14 tables. (DLC)

  19. Challenge problem and milestones for : Nuclear Energy Advanced Modeling and Simulation (NEAMS) waste Integrated Performance and Safety Codes (IPSC).

    Energy Technology Data Exchange (ETDEWEB)

    Freeze, Geoffrey A.; Wang, Yifeng; Howard, Robert; McNeish, Jerry A.; Schultz, Peter Andrew; Arguello, Jose Guadalupe, Jr.

    2010-09-01

    This report describes the specification of a challenge problem and associated challenge milestones for the Waste Integrated Performance and Safety Codes (IPSC) supporting the U.S. Department of Energy (DOE) Office of Nuclear Energy Advanced Modeling and Simulation (NEAMS) Campaign. The NEAMS challenge problems are designed to demonstrate proof of concept and progress towards IPSC goals. The goal of the Waste IPSC is to develop an integrated suite of modeling and simulation capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive waste storage or disposal system. The Waste IPSC will provide this simulation capability (1) for a range of disposal concepts, waste form types, engineered repository designs, and geologic settings, (2) for a range of time scales and distances, (3) with appropriate consideration of the inherent uncertainties, and (4) in accordance with robust verification, validation, and software quality requirements. To demonstrate proof of concept and progress towards these goals and requirements, a Waste IPSC challenge problem is specified that includes coupled thermal-hydrologic-chemical-mechanical (THCM) processes that describe (1) the degradation of a borosilicate glass waste form and the corresponding mobilization of radionuclides (i.e., the processes that produce the radionuclide source term), (2) the associated near-field physical and chemical environment for waste emplacement within a salt formation, and (3) radionuclide transport in the near field (i.e., through the engineered components - waste form, waste package, and backfill - and the immediately adjacent salt). The initial details of a set of challenge milestones that collectively comprise the full challenge problem are also specified.

  20. Commercial and Industrial Solid Waste Incineration Units (CISWI): New Source Performance Standards (NSPS) and Emission Guidelines (EG) for Existing Sources

    Science.gov (United States)

    Learn about the New Source Performance Standards (NSPS) for commercial and industrial solid waste incineration (CISWI) units including emission guidelines and compliance times for the rule. Read the rule history and summary, and find supporting documents

  1. Strategy for identifying natural analogs of the long-term performance of low-level waste disposal sites

    Energy Technology Data Exchange (ETDEWEB)

    Chatters, J.C.; Waugh, W.J.; Foley, M.G.; Kincaid, C.T.

    1990-07-01

    The US Department of Energy's Low-Level Waste (LLW) Management Program has asked Pacific Northwest Laboratory (PNL) to explore the feasibility of using natural analogs of anticipated waste site and conditions to help validate predictions of the performance of LLW disposal sites. Current regulations require LLW facilities to control the spread of hazardous substances into the environment for at least the next 500 years. Natural analog studies can provide information about processes affecting waste containment that cannot be fully explored through laboratory experimentation and modeling because of the extended period of required performance. For LLW applications, natural analogs include geochemical systems, pedogenic (soil formation) indicators, proxy climate data, and ecological and archaeological settings that portray long-term changes in disposal site environments and the survivability of proposed waste containment materials and structures. Analog data consist of estimates of performance assessment (PA) model input parameters that define possible future environmental states of waste sites, validation parameters that can be predicted by PA models, and descriptive information that can build public confidence in waste disposal practices. This document describes PNL's overall stategy for identifying analogs for LLW disposal systems, reviews lessons learned from past analogs work, outlines the findings of the workshop, and presents examples of analog studies that workshop participants found to be applicable to LLW performance assessment. The lessons from the high-level waste analogs experience and workshop discussions will be used to develop detailed study plans during FY 1990. 39 refs.

  2. Effect of solidification conditions on the solidification mode in austenitic stainless steels

    Science.gov (United States)

    Suutala, N.

    1983-02-01

    The effect of the solidification conditions on the solidification mode in the composition range in which the primary austenitic and ferritic modes compete is studied by varying the welding parameters in gas tungsten arc (GTA) welding and by comparing the results with those obtained from other laboratory experiments. A good agreement holds if the effect of the composition is described by the ratio Creq/Nieq (Creq = pct Cr + 1.37 × pct Mo + 1.5 × pct Si + 2 × pct Nb + 3 × pct Ti and Nieq = pct Ni + 0.31 × pct Mn + 22 × pct C + 14.2 × pct N + pct Cu) and the effect of the solidification conditions by the growth rate. The critical value of the ratio Creq/Nieq corresponding to the transition from primary austenitic to ferritic solidification increases from 1.43 to 1.55 with increasing growth rate. The upper limit is valid in GTA welding at high welding speeds, while the lower limit corresponds to the practical conditions which exist in ingot and shaped casting. The validity and applicability of this solidification model are discussed.

  3. Construction Waste Management Profiles, Practices, and Performance: A Cross-Jurisdictional Analysis in Four Countries

    Directory of Open Access Journals (Sweden)

    Vivian Wing-Yan Tam

    2016-02-01

    Full Text Available Construction waste management (CWM has received worldwide attention for some time. As a result, a plethora of research, investigating a wide array of CWM issues such as their profiles, practices, and performance, has been reported in individual economies around the globe. However, a cross-jurisdictional comparison of these issues is limitedly presented in the literature despite its importance to benchmarking performance and identifying best CWM practices in the context of globalization whereby knowledge sharing has already transcended traditional country boundaries. The aim of this ex post facto research is to compare CWM profiles, practices, and performance in Australia, Europe (Europe refers to EU-27 member countries in the European Union, including Belgium, France, Germany, Italy, Luxembourg, Netherlands, Denmark, Great Britain, Ireland, Portugal, Spain, Greece, Austria, Finland, Sweden, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia, Slovenia, Malta, Cyprus, Bulgaria, and Romania., Hong Kong, and the United Kingdom at a national-level, with a view to facilitating CWM knowledge sharing internationally. It does so by triangulating empirical data collected from various national statistical yearbooks with research papers and professional reports on CWM in these economies. It is found that in producing one million (US dollars’ work, construction contributes a volume of solid waste ranging from 28 to 121 tons among countries. Conscientious CWM practices can make a significant difference in reducing, reusing, or recycling construction waste, as evident in the large variation in the CWM performance. While it might be oversimplified to conclude that the best practices in one country can be applied in another, the research provides insightful references into sharing CWM knowledge across boundaries.

  4. Phase-field modeling of directional solidification

    Science.gov (United States)

    Echebarria, Blas; Karma, Alain

    2001-06-01

    Phase-field models have become an important tool to simulate interfacial pattern formation in solidification and other systems. Here we investigate the directional solidification of a dilute binary alloy by means of a new phase-field model. The thin interface limit of this model yields a much less stringent restriction on the choice of interface thickness than previous models and permits, in addition, to eliminate non-equilibrium effects at the interface that are typically negligibly small in low growth rate experiments. Simulations of this model are used to investigate the interface evolution far above the onset of morphological instability for realistic values of the physical parameters and to make quantitative comparisons with experiments.

  5. Simulation of spreading with solidification: assessment synthesis of Thema code

    Energy Technology Data Exchange (ETDEWEB)

    Spindler, B.; Veteau, J.M. [CEA Grenoble, Direction de l' Energie Nucleaire, Dept. de Technologie Nucleaire, Service d' Etudes Thermohydrauliques et Technologiques, 38 (France)

    2004-07-01

    After a presentation of the models included in THEMA code, which simulates the spreading of a fluid with solidification, the whole assessment calculations are presented. The first series concerns the comparison with analytical or numerical solutions: dam break, conduction for the heat transfer in the substrate, crust growth. The second series concerns the comparison with the CORINE isothermal tests (simulating fluid at low temperature). The third series concerns the CORINE tests with heat transfer. The fourth series concerns the tests with simulating materials at medium or high temperature (RIT, KATS). The fifth series concerns the tests with prototypical materials (COMAS, FARO, VULCANO). Finally the blind simulations of the ECOKATS tests are presented. All the calculations are performed with the same physical models (THEMA version 2.5), without any variable tuning parameter according to the test under consideration. Sensitivity studies concern the influence of the viscosity model in the solidification interval, and for the tests with prototypical materials the inlet temperature and the solid fraction. The relative difference between the calculated and measured spreading areas is generally less than 20 % except for the test with prototypical materials, for which the assessment is not easy due to the large experimental uncertainties. The level of validation of THEMA is considered as satisfactory, taking into account the required accuracy. (authors)

  6. Quantitative phase-field model of alloy solidification

    Science.gov (United States)

    Echebarria, Blas; Folch, Roger; Karma, Alain; Plapp, Mathis

    2004-12-01

    We present a detailed derivation and thin interface analysis of a phase-field model that can accurately simulate microstructural pattern formation for low-speed directional solidification of a dilute binary alloy. This advance with respect to previous phase-field models is achieved by the addition of a phenomenological “antitrapping” solute current in the mass conservation relation [A. Karma, Phys. Rev. Lett. 87, 115701 (2001)]. This antitrapping current counterbalances the physical, albeit artificially large, solute trapping effect generated when a mesoscopic interface thickness is used to simulate the interface evolution on experimental length and time scales. Furthermore, it provides additional freedom in the model to suppress other spurious effects that scale with this thickness when the diffusivity is unequal in solid and liquid [R. F. Almgren, SIAM J. Appl. Math. 59, 2086 (1999)], which include surface diffusion and a curvature correction to the Stefan condition. This freedom can also be exploited to make the kinetic undercooling of the interface arbitrarily small even for mesoscopic values of both the interface thickness and the phase-field relaxation time, as for the solidification of pure melts [A. Karma and W.-J. Rappel, Phys. Rev. E 53, R3017 (1996)]. The performance of the model is demonstrated by calculating accurately within a phase-field approach the Mullins-Sekerka stability spectrum of a planar interface and nonlinear cellular shapes for realistic alloy parameters and growth conditions.

  7. Investigation of solidification dynamics of Zr-based alloys

    Energy Technology Data Exchange (ETDEWEB)

    Kobold, Raphael; Herlach, Dieter [Institut fuer Materialphysik im Weltraum, Deutsches Zentrum fuer Luft- und Raumfahrt, 51170 Koeln (Germany); Ruhr-Universitaet Bochum, 44780 Bochum (Germany)

    2013-07-01

    In contrast to experiments with most undercooled binary alloys the velocity of dendritic growth of a Cu50Zr50 alloy does not increase monotonically with undercooling but passes through a maximum and then decreases. To study this behaviour we investigate Zr-based alloys such as CuZr, NiZr and NiZrAl with Zirconium concentrations ranging from 36 to 64 at.% including eutectic and intermetallic phases. We use electrostatic levitation technique to melt and undercool samples with a diameter of 2-3 mm under ultra-high-vacuum conditions. Containerless processing is an effective tool for undercooling metallic melts far below their equilibrium melting temperatures since heterogeneous nucleation on container walls is completely avoided. During crystallisation of the undercooled melt the heat of crystallisation is released. The rapid increase of the temperature at the solid-liquid interface makes the solidification front visible. The velocities of the solidification front are recorded by using a high-speed camera with a maximum rate of 50.000 frames per second and are analyzed with a software for optical ray tracing. Furthermore, we try to model the growth velocity vs. the undercooling temperature and perform sample EBSD analysis with a scanning electron microscope.

  8. Enhancing anaerobic digestion performance of crude lipid in food waste by enzymatic pretreatment.

    Science.gov (United States)

    Meng, Ying; Luan, Fubo; Yuan, Hairong; Chen, Xue; Li, Xiujin

    2017-01-01

    Three lipases were applied to hydrolyze the floatable grease (FG) in the food waste for eliminating FG inhibition and enhancing digestion performance in anaerobic process. Lipase-I, Lipase-II, and Lipase-III obtained from different sources were used. Animal fat (AF) and vegetable oil (VO) are major crude lipids in Chinese food waste, therefore, applied as substrates for anaerobic digestion tests. The results showed that Lipase-I and Lipase-II were capable of obviously releasing long chain fatty acid in AF, VO, and FG when hydrolyzed in the conditions of 24h, 1000-1500μL and 40-50°C. Compared to the untreated controls, the biomethane production rate were increased by 80.8-157.7%, 26.9-53.8%, and 37.0-40.7% for AF, VO, and FG, respectively, and the digestion time was shortened by 10-40d. The finding suggests that pretreating lipids with appropriate lipase could be one of effective methods for enhancing anaerobic digestion of food waste rich in crude lipid. Copyright © 2016. Published by Elsevier Ltd.

  9. SPARTAN: a simple performance assessment code for the Nevada Nuclear Waste Storage Investigations Project

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Y.T.

    1985-12-01

    SPARTAN is a simple computer model designed for the Nevada Nuclear Waste Storage Investigations Project to calculate radionuclide transport in geologic media. The physical processes considered are limited to Darcy`s flow, radionuclide decay, and convective transport with constant retardation of radionuclides relative to water flow. Inputs for the model must be provided for the geometry, repository area, flow path, water flux, effective porosity, initial inventory, waste solubility, canister lifetime, and retardation factors. Results from the model consist of radionuclide release rates from the prospective Yucca Mountain repository for radioactive waste and cumulative curies released across the flow boundaries at the end of the flow path. The rates of release from the repository relative to NRC performance objectives and releases to the accessible environment relative to EPA requirements are also calculated. Two test problems compare the results of simulations from SPARTAN with analytical solutions. The comparisons show that the SPARTAN solution closely matches the analytical solutions across a range of conditions that approximate those that might occur at Yucca Mountain.

  10. Synthesis of Petroleum-Based Fuel from Waste Plastics and Performance Analysis in a CI Engine

    Directory of Open Access Journals (Sweden)

    Christine Cleetus

    2013-01-01

    Full Text Available The present work involves the synthesis of a petroleum-based fuel by the catalytic pyrolysis of waste plastics. Catalytic pyrolysis involves the degradation of the polymeric materials by heating them in the absence of oxygen and in the presence of a catalyst. In the present study different oil samples are produced using different catalysts under different reaction conditions from waste plastics. The synthesized oil samples are subjected to a parametric study based on the oil yield, selectivity of the oil, fuel properties, and reaction temperature. Depending on the results from the above study, an optimization of the catalyst and reaction conditions was done. Gas chromatography-mass spectrometry of the selected optimized sample was done to find out its chemical composition. Finally, performance analysis of the selected oil sample was carried out on a compression ignition (CI engine. Polythene bags are selected as the source of waste plastics. The catalysts used for the study include silica, alumina, Y zeolite, barium carbonate, zeolite, and their combinations. The pyrolysis reaction was carried at polymer to catalyst ratio of 10 : 1. The reaction temperature ranges between 400°C and 550°C. The inert atmosphere for the pyrolysis was provided by using nitrogen as a carrier gas.

  11. Performance evaluation of a full-scale innovative swine waste-to-energy system.

    Science.gov (United States)

    Xu, Jiele; Adair, Charles W; Deshusses, Marc A

    2016-09-01

    Intensive monitoring was carried out to evaluate the performance of a full-scale innovative swine waste-to-energy system at a commercial swine farm with 8640 heads of swine. Detailed mass balances over each unit of the system showed that the system, which includes a 7600m(3) anaerobic digester, a 65-kW microturbine, and a 4200m(3) aeration basin, was able to remove up to 92% of the chemical oxygen demand (COD), 99% of the biological oxygen demand (BOD), 77% of the total nitrogen (TN), and 82% of the total phosphorous (TP) discharged into the system as fresh pig waste. The overall biogas yield based on the COD input was 64% of the maximum theoretical, a value that indicates that even greater environmental benefits could be obtained with process optimization. Overall, the characterization of the materials fluxes in the system provides a greater understanding of the fate of organics and nutrients in large scale animal waste management systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Summary discussion of the 1996 performance assessment for the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    HELTON,JON CRAIG; ANDERSON,D. RICHARD; BASABILVAZO,G.; JOW,HONG-NIAN; MARIETTA,MELVIN G.

    2000-05-19

    The Waste Isolation Pilot Plant (WIPP) is under development by the US Department of Energy (DOE) for the geologic disposal of transuranic waste. The construction of complementary cumulative distribution functions (CCDFs) for total radionuclide release from the WIPP to the accessible environment is described. The resultant CCDFs (1) combine releases due to cuttings and cavings, spallings, direct brine release, and long-term transport in flowing groundwater, (2) fall substantially to the left of the boundary line specified by the U.S. Environmental Protection Agency's (EPA's) standard 40 CFR 191 for the geologic disposal of radioactive waste, and (3) constitute an important component of the DOE's successful Compliance Certification Application to the EPA for the WIPP. Insights and perspectives gained in the performance assessment (PA) that led to these CCDFs are described, including the importance of (1) an iterative approach to PA, (2) uncertainty and sensitivity analysis, (3) a clear conceptual model for the analysis, (4) the separation of stochastic (i.e., aleatory) and subjective (i.e., epistemic) uncertainty, (5) quality assurance procedures, (6) early involvement of peer reviewers, regulators, and stake holders, (7) avoidance of conservative assumptions, and (8) adequate documentation.

  13. Historical Background on Assessment the Performance of the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P.

    1999-06-01

    In 1979, six years after selecting the Delaware Basin as a potential disposal area, Congress authorized the US Department of Energy to build the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico, as a research and development facility for the safe management, storage, and disposal of waste contaminated with transuranic radioisotopes. In 1998, 19 years after authorization and 25 years after site selection, the US Environmental Protection Agency (EPA) certified that the WIPP disposal system complied with its regulations. The EPA's decision was primarily based on the results from a performance assessment conducted in 1996. This performance assessment was the culmination of four preliminary performance assessments conducted between 1989 and 1992. This report provides a historical setting and context for how the performance of the deep geologic repository at the WIPP was analyzed. Also included is background on political forces acting on the project. For example, the federal requirement to provide environmental impact statements and negotiated agreements with the State of New Mexico influenced the type of scientific areas that were investigated and the engineering analysis prior to 1989 for the WIPP.

  14. Molecular dynamics modelling of solidification in metals

    Energy Technology Data Exchange (ETDEWEB)

    Boercker, D.B.; Belak, J.; Glosli, J. [Lawrence Livermore National Lab., CA (United States)

    1997-12-31

    Molecular dynamics modeling is used to study the solidification of metals at high pressure and temperature. Constant pressure MD is applied to a simulation cell initially filled with both solid and molten metal. The solid/liquid interface is tracked as a function of time, and the data are used to estimate growth rates of crystallites at high pressure and temperature in Ta and Mg.

  15. Constraints to Strategy Implementation and their Influence on Business Performance: the Case of a Waste Management Logistics Company

    Directory of Open Access Journals (Sweden)

    Chengedzai Mafini

    2016-08-01

    Full Text Available Waste management companies in developing countries often have to contend with a plethora of factors that inhibit their business performance. The primary objective of this study was to investigate the influence of constraints to strategy implementation on the business performance of a waste management logistics company in South Africa. The study was triggered by the lack of previous research focusing on constraints to strategy implementation in the waste management sector. The study employed a quantitative approach using the cross sectional survey design in which data were collected from 309 employees of a waste management logistics company based in Gauteng Province. Seven constraints to strategy implementation; namely, management practices, human resource capabilities, customer service, external orientation, internal communication, innovation and employee motivation were identified through Exploratory Factor Analysis. Pearson correlations showed that business performance is negatively affected as and when each constraint becomes more prevalent. Regression analysis showed that all constraints were statistically significant. To academics, the study provides current insights on factors impacting on business performance in waste management organisations. Management practitioners may improve the levels of business performance through structural adjustments of the seven constraints identified in this study. The study may be used as a reference point in the diagnosis of business performance related challenges in companies operating within the waste management sector.

  16. Interface dynamics and banding in rapid solidification

    Energy Technology Data Exchange (ETDEWEB)

    Karma, A.; Sarkissian, A. (Physics Department, Northeastern University, Boston, Massachusetts 02115 (United States))

    1993-01-01

    Rapid-solidification experiments on metallic alloys in the last decade have provided widespread observations of a novel banded structure.'' We report the results of numerical and analytical studies of the interface dynamics underlying the formation of this structure in a model of directional solidification which includes both solute and heat diffusion and nonequilibrium effects. The thrust of these studies is on the unsteady dynamics of the planar interface and thermal effects. The main conclusion is that the origin of banding can be related to relaxation oscillations of the solidification front, characterized by large variations of the interface velocity, which are dramatically affected by latent-heat diffusion. Without the latter, the oscillations are found to be reasonably well approximated by the phenomenological model of Carrard [ital et] [ital al]. [Acta Metall. 40, 983 (1992)], and the band spacing is inversely proportional to the temperature gradient. In contrast, with latent-heat diffusion the band spacing is insensitive to the temperature gradient, but is controlled instead by the interplay of solute and heat diffusion. The smallness of the solutal diffusivity to thermal diffusivity ratio is exploited to explain analytically this effect and to derive considerably simpler equations of interface motion that provide an efficient numerical means to study the nonplanar interface dynamics expected to cause dark bands. A reasonable agreement with experiment is found for the spacing of banded structures dominated by light-band microsegregation-free regions in Al-Fe alloys.

  17. Numerical models for casting solidification: Part II. Application of the boundary element method to solidification problems

    Science.gov (United States)

    Hong, C. P.; Umeda, T.; Kimura, Y.

    1984-01-01

    A new numerical model, which is based on the boundary element method, was proposed for the simulation of solidification problems, and its application was demonstrated for solidification of metals in metal and sand molds. Comparisons were made between results from this model and those from the explicit finite difference method. Temperature recovery method was successfully adopted to estimate the liberation of latent heat of freezing in the boundary element method. A coupling method was proposed for problems in which the boundary condition of the interface consisting of inhomogeneous bodies is governed by Newton’s law of cooling in the boundary element method. It was concluded that the boundary element method which has several advantages, such as the wide variety of element shapes, simplicity of data preparation, and small CPU times, will find wide application as an alternative for finite difference or finite element methods, in the fields of solidification problems, especially for complex, three-dimensional geometries.

  18. Investigation of the Performance of a Heat Pump Using Waste Water as a Heat Source

    Directory of Open Access Journals (Sweden)

    Ali Kahraman

    2009-08-01

    Full Text Available In this research, a water-water heat pump system using waste water as a heat source, a type that is not often used in Turkey and the World, was experimentally modeled. The experiments were performed under the conditions of simulated waste water temperature values of 20 °C, 30 °C and 40 °C. Inlet and outlet water temperatures of the evaporator and condenser, water flow rates in the evaporator and condenser circuits, pressures at the compressor inlet and outlet and power consumption of the system were measured. The heating coefficients of performance were calculated based on the measurements. It was found that the maximum temperature in the energy storage tank was about 50.6 °C. For the heat source temperatures of 20 °C, 30 °C and 40 °C, the heating coefficients of the performance of the system became 3.36, 3.43 and 3.69, respectively, 6 min. after the start time of the experiments and then they were decreased to 1.87, 1.83 and 1.77 with increasing water temperature in the condenser tank. The mean uncertainty value of the measurement parameters was found to be about ±2.47%. Finally, for the purpose of meeting hot water need as well as floor heating system requirements, it is seen that energy quality level of a waste low grade temperature heat source can be increased by using a heat pump system.

  19. Innovative Solidification Techniques for Hazardous Wastes at Army Installations.

    Science.gov (United States)

    1985-11-01

    6.35-cm wire mesh, dried at 40* C, and ground with a mortar and pestle. The particle-size distribution of the soil is shown in Figure 3. The flyash was...the liquid with soil in order to adsorb copper. The resulting slurry was solidified using flyash and lime as setting agents. In order to investigate...0 9 . . . . .. . * . 0 0 49 REFERENCES a & o . o . . . * o o 9 o o o e o 9 o 9 e o o 50 APPENDIX A: FLYASH POZZOLAN REPORT . ............... .. Al 2

  20. Waste Form Release Data Package for the 2005 Integrated Disposal Facility Performance Assessment. Erratum

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Gary L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-06

    This report refers to or contains Kg values for glasses LAWA44, LAWB45 and LAWC22 affected by calculations errors as identified by Papathanassiu et al. (2011). The corrected Kg values are reported in an erratum included in the revised version of the original report. The revised report can be referenced as follows: Pierce E. M. et al. (2004) Waste Form Release Data Package for the 2005 Integrated Disposal Facility Performance Assessment. PNNL-14805 Rev. 0 Erratum. Pacific Northwest National Laboratory, Richland, WA, USA.

  1. Recharge Data Package for the Immobilized Low-Activity Waste 2001 Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    MJ Fayer; EM Murphy; JL Downs; FO Khan; CW Lindenmeier; BN Bjornstad

    2000-01-18

    Lockheed Martin Hanford Company (LMHC) is designing and assessing the performance of disposal facilities to receive radioactive wastes that are currently stored in single- and double-shell tanks at the Hanford Site. The preferred method of disposing of the portion that is classified as immobilized low-activity waste (ILAW) is to vitrify the waste and place the product in near-surface, shallow-land burial facilities. The LMHC project to assess the performance of these disposal facilities is known as the Hanford ILAW Performance Assessment (PA) Activity, hereafter called the ILAW PA project. The goal of this project is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface-water resources, and inadvertent intruders. Achieving this goal will require predictions of contaminant migration from the facility. To make such predictions will require estimates of the fluxes of water moving through the sediments within the vadose zone around and beneath the disposal facility. These fluxes, loosely called recharge rates, are the primary mechanism for transporting contaminants to the groundwater. Pacific Northwest National Laboratory (PNNL) assists LMHC in their performance assessment activities. One of the PNNL tasks is to provide estimates of recharge rates for current conditions and long-term scenarios involving the shallow-land disposal of ILAW. Specifically, recharge estimates are needed for a filly functional surface cover; the cover sideslope, and the immediately surrounding terrain. In addition, recharge estimates are needed for degraded cover conditions. The temporal scope of the analysis is 10,000 years, but could be longer if some contaminant peaks occur after 10,000 years. The elements of this report compose the Recharge Data Package, which provides estimates of recharge rates for the scenarios being considered in the 2001 PA. Table S.1 identifies the surface features and

  2. An appraisal of the 1992 preliminary performance assessment for the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lee, W.W.L.; Chaturvedi, L.; Silva, M.K.; Weiner, R.; Neill, R.H. [Environmental Evaluation Group, Albuquerque, NM (United States)]|[Environmental Evaluation Group, Carlsbad, NM (United States)

    1994-09-01

    The purpose of the New Mexico Environmental Evaluation Group is to conduct an independent technical evaluation of the Waste Isolation Pilot Plant (WIPP) Project to ensure the protection of the public health and safety and the environment. The WIPP Project, located in southeastern New Mexico, is being constructed as a repository for the disposal of transuranic (TRU) radioactive wastes generated by the national defense programs. The Environmental Evaluation Group (EEG) has reviewed the WIPP 1992 Performance Assessment (Sandia WIPP Performance Assessment Department, 1992). Although this performance assessment was released after the October 1992 passage of the WIPP Land Withdrawal Act (PL 102-579), the work preceded the Act. For individual and ground-water protection, calculations have been done for 1000 years post closure, whereas the US Environmental Protection Agency`s Standards (40 CFR 191) issued in 1993 require calculations for 10,000 years. The 1992 Performance Assessment continues to assimilate improved understanding of the geology and hydrogeology of the site, and evolving conceptual models of natural barriers. Progress has been made towards assessing WIPP`s compliance with the US Environmental Protection Agency`s Standards (40 CFR 191). The 1992 Performance Assessment has addressed several items of major concern to EEG, outlined in the July 1992 review of the 1991 performance assessment (Neill et al., 1992). In particular, the authors are pleased that some key results in this performance assessment deal with sensitivity of the calculated complementary cumulative distribution functions (CCDF) to alterative conceptual models proposed by EEG -- that flow in the Culebra be treated as single-porosity fracture-flow; with no sorption retardation unless substantiated by experimental data.

  3. Performance of gas diffusion layer from coconut waste for proton exchange membrane fuel cell

    Science.gov (United States)

    Widodo, H.; Destyorini, F.; Insiyanda, D. R.; Subhan, A.

    2017-04-01

    The performance of Gas Diffusion Layer (GDL) synthesized from coconut waste. Gas Diffusion Layer (GDL), produced from coconut waste, as a part of Proton Exchange Membrane Fuel Cell (PEMFC) component, has been characterized. In order to know the performance, the commercial products were used as the remaining parts of PEMFC. The proposed GDL possesses 69% porosity for diffusion of Hydrogen fuel and Oxygen, as well as for transporting electron. With the electrical conductivity of 500 mS.cm-1, it also has hydrophobic properties, which is important to avoid the reaction with water, with the contact angle of 139°. The 5 × 5 cm2 GDL paper was co-assembled with the catalyst, Nafion membrane, bipolar plate, current collector, end plate to obtain single Stack PEMFC. The performance was examined by flowing fuel and gas with the flow rate of 500 and 1000 ml.min-1, respectively, and analyse the I-V polarization curve. The measurements were carried out at 30, 35, and 40°C for 5 cycles to ensure the repeatability. The results shows that the current density and the maximum power density reaches 203 mA.cm-2 and 143 mW.cm-2, respectively, with a given voltage 0.6 V, at 40°C.

  4. Performance assessment on grouted double-shell tank waste at Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, D.H; McNair, G.W. [Pacific Northwest Lab., Richland, WA (United States); Allison, J.M. [Westinghouse Hanford Co., Richland, WA (United States)

    1989-11-01

    The low-level fraction of liquid waste stored in double-shell tanks at Hanford will be solidified in a cementitious matrix (grout) and disposed in subsurface vaults. This paper discusses activities related to the preparation of a site-specific performance assessment as required by DOE Order 5820.2A. A draft performance assessment has been prepared for the planned grout disposal system at Hanford using site-specific data. The assessment estimates the incremental increase in the dose to future populations who, after loss of institutional control at the site, use groundwater downgradient of the disposal site. Increases in nonradiological species in water from a hypothetical well are also estimated. Two-dimensional transport models were used to estimate contaminant concentrations in groundwater. Based on diffusional release from the waste package, the projected radiological dose to an individual on a hypothetical farm using water from a well at the disposal facility boundary is estimated at less than one percent of the 25 mrem/yr standard in Order 5820.2. Technetium accounted for about 95% of the dose. Nitrate was the principle chemical contaminant at 0.3% to 0.5% of apportioned drinking water standards. Sensitivity studies on various parameters are in progress. This performance assessment will be updated as additional data become available.

  5. Investigation of Performance and Emissions Effects of Waste Vegetable Oil Methyl Ester in A Diesel Engine

    Directory of Open Access Journals (Sweden)

    Yahya ULUSOY

    2016-12-01

    Full Text Available In this study engine and emission performance of a 4-stroke, 4 cylinder, direct injection 62,5 kW engine, with three different biodiesel blends (B25, B50, B75,  was compared with those obtained with use of normal diesel (B0 through a 8-mode experimental test procedure, in convention with ISO 8178-C1. The results of the study showed that, performance and emission values of biodiesel fuels produced from vegetable oil and those obtained with diesel fuel (B0 are very close to each other.  In this context, the waste cooking oil, which is a serious risk to the environment and should be collected according to related legistlative measures,  could be processed to and used as biodiesel without creating any significant loss in terms of engine performance, while providing significant advantages in terms of engine emissions. These results revealed that, waste frying oils can be used as diesel fuel and to create an adding value for the economy instead of being potential environmental risk. 

  6. Use of alternative waste materials in producing ultra-high performance concrete

    Directory of Open Access Journals (Sweden)

    Ahmad Shamsad

    2017-01-01

    Full Text Available In a corrosive environment similar to that of the Arabian Gulf, use of high-performance concrete is one of the options to ensure a target service life of concrete structures. However, in absence of good quality coarse aggregates, it is a challenging task to produce high-performance concrete. Recently, the possibility of producing ultra-high-performance concrete (UHPC has been widely reported in the literature. UHPC is produced without coarse aggregates at very low water to cementitious materials ratio, high amounts of cement, mineral admixtures, and superplasticizer along with fine quartz sand as aggregate, quartz powder as micro-filler, a nd steel fibres for fracture toughness. In the present work, an effort was made to utilize local waste materials as alternative mineral admixtures and local dune sand as aggregate in producing different UHPC mixtures without addition of quartz powder. The mechanical properties, shrinkage, and durability characteristics of the UHPC mixtures were studied. Test results indicate that it is possible to produce UHPC mixtures using alternative waste materials, which would have targeted flow, strength, toughness, and resistance against reinforcement corrosion. The information presented in the paper would help in optimum selection of a mixture of UHPC considering the availability of local materials, exposure conditions and structural requirements.

  7. Development of a High Chromium Ni-Base Filler Metal Resistant to Ductility Dip Cracking and Solidification Cracking

    Science.gov (United States)

    Hope, Adam T.

    Many nuclear reactor components previously constructed with Ni-based alloys containing 20 wt% Cr have been found to be susceptible to stress corrosion cracking. The nuclear power industry now uses high chromium (˜30wt%) Ni-based filler metals to mitigate stress corrosion cracking. Current alloys are plagued with weldability issues, either solidification cracking or ductility dip cracking (DDC). Solidification cracking is related to solidification temperature range and the DDC is related to the fraction eutectic present in the microstructure. It was determined that an optimal alloy should have a solidification temperature range less than 150°C and at least 2% volume fraction eutectic. Due to the nature of the Nb rich eutectic that forms, it is difficult to avoid both cracking types simultaneously. Through computational modeling, alternative eutectic forming elements, Hf and Ta, have been identified as replacements for Nb in such alloys. Compositions have been optimized through a combination of computational and experimental techniques combined with a design of experiment methodology. Small buttons were melted using commercially pure materials in a copper hearth to obtain the desired compositions. These buttons were then subjected to a gas tungsten arc spot weld. A type C thermocouple was used to acquire the cooling history during the solidification process. The cooling curves were processed using Single Sensor Differential Thermal Analysis to determine the solidification temperature range, and indicator of solidification cracking susceptibility. Metallography was performed to determine the fraction eutectic present, an indicator of DDC resistance. The optimal level of Hf to resist cracking was found to be 0.25 wt%. The optimal level of Ta was found to be 4 wt%. gamma/MC type eutectics were found to form first in all Nb, Ta, and Hf-bearing compositions. Depending on Fe and Cr content, gamma/Laves eutectic was sometimes found in Nb and Ta-bearing compositions, while

  8. Property Measurements and Solidification Studies by Electrostatic Levitation

    National Research Council Canada - National Science Library

    PARADIS, PAUL‐FRANÇOIS; YU, JIANDING; ISHIKAWA, TAKEHIKO; YODA, SHINICHI

    2004-01-01

    A bstract : The National Space Development Agency of Japan has recently developed several electrostatic levitation furnaces and implemented new techniques and procedures for property measurement, solidification...

  9. Ultrasound-assisted surfactant-enhanced emulsification microextraction with solidification of floating organic droplet followed by high performance liquid chromatography for the determination of strobilurin fungicides in fruit juice samples.

    Science.gov (United States)

    Liang, Pei; Liu, Guojiao; Wang, Fang; Wang, Wanting

    2013-05-01

    A novel method, ultrasound-assisted surfactant-enhanced emulsification microextraction with solidification of floating organic droplet (UASEME-SFOD), has been developed for the extraction of four strobilurin fungicides (kresoxim-methyl, picoxystrobin, pyraclostrobin and trifloxystrobin) in fruit juices. In the UASEME-SFOD technique, Tween 80 was used as emulsifier, and 1-undecanol was used as extraction solvent without using any organic dispersive solvent. Several parameters that affect the extraction efficiency, such as the kind and volume of extraction solvent, the type and concentration of the surfactant, extraction time, extraction temperature and salt addition were investigated and optimized. Under the optimum extraction condition, the method yields a linear calibration curve in the concentration range from 5 to 10,000 ng mL(-1) for the targeted analytes with the correlation coefficient ranging from 0.9991 to 0.9998. The enrichment factors were in the range between 95 and 135, and the limits of detection of the method were 2-4 ng mL(-1). The fruit juice samples were successfully analyzed using the proposed method, and the relative recoveries at fortified levels of 50 and 100 ng mL(-1) were in the range of 82.6-97.5%. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Supplemental Immobilization of Hanford Low-Activity Waste: Cast Stone Screening Tests

    Energy Technology Data Exchange (ETDEWEB)

    Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Piepel, Gregory F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lindberg, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Heasler, Patrick G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mercier, Theresa M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Russell, Renee L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cozzi, Alex [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Daniel, William E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Eibling, Russell E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hansen, E. K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Reigel, Marissa M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Swanberg, David J. [Washington River Protection Solutions (WRPS), Aiken, SC (United States)

    2013-09-30

    More than 56 million gallons of radioactive and hazardous waste are stored in 177 underground storage tanks at the U.S. Department of Energy’s (DOE’s) Hanford Site in southeastern Washington State. The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the wastes and immobilize them in a glass waste form. The WTP includes a pretreatment facility to separate the wastes into a small volume of high-level waste (HLW) containing most of the radioactivity and a larger volume of low-activity waste (LAW) containing most of the nonradioactive chemicals. The HLW will be converted to glass in the HLW vitrification facility for ultimate disposal at an offsite federal repository. At least a portion (~35%) of the LAW will be converted to glass in the LAW vitrification facility and will be disposed of onsite at the Integrated Disposal Facility (IDF). The pretreatment and HLW vitrification facilities will have the capacity to treat and immobilize the wastes destined for each facility. However, a second LAW immobilization facility will be needed for the expected volume of LAW requiring immobilization. A cementitious waste form known as Cast Stone is being considered to provide the required additional LAW immobilization capacity. The Cast Stone waste form must be acceptable for disposal in the IDF. The Cast Stone waste form and immobilization process must be tested to demonstrate that the final Cast Stone waste form can comply with the waste acceptance criteria for the disposal facility and that the immobilization processes can be controlled to consistently provide an acceptable waste form product. Further, the waste form must be tested to provide the technical basis for understanding the long-term performance of the waste form in the disposal environment. These waste form performance data are needed to support risk assessment and performance assessment (PA) analyses of the long-term environmental impact of the waste disposal in the IDF

  11. Utilization of air pollution control residues for the stabilization/solidification of trace element contaminated soil.

    Science.gov (United States)

    Travar, I; Kihl, A; Kumpiene, J

    2015-12-01

    The aim of this study was to evaluate the stabilization/solidification (S/S) of trace element-contaminated soil using air pollution control residues (APCRs) prior to disposal in landfill sites. Two soil samples (with low and moderate concentrations of organic matter) were stabilized using three APCRs that originated from the incineration of municipal solid waste, bio-fuels and a mixture of coal and crushed olive kernels. Two APCR/soil mixtures were tested: 30% APCR/70% soil and 50% APCR/50% soil. A batch leaching test was used to study immobilization of As and co-occurring metals Cr, Cu, Pb and Zn. Solidification was evaluated by measuring the unconfined compression strength (UCS). Leaching of As was reduced by 39-93% in APCR/soil mixtures and decreased with increased amounts of added APCR. Immobilization of As positively correlated with the amount of Ca in the APCR and negatively with the amount of soil organic matter. According to geochemical modelling, the precipitation of calcium arsenate (Ca3(AsO4)2/4H2O) and incorporation of As in ettringite (Ca6Al2(SO4)3(OH)12 · 26H2O) in soil/APCR mixtures might explain the reduced leaching of As. A negative effect of the treatment was an increased leaching of Cu, Cr and dissolved organic carbon. Solidification of APCR/soil was considerably weakened by soil organic matter.

  12. Growth performance of free-range village chickens fed dehydrated processed food waste

    Directory of Open Access Journals (Sweden)

    Hossein, S.

    2015-06-01

    Full Text Available The effect of dehydrated processed food waste (DPFW inclusion in the diets on the growth performance (feed intake, body weight gain, body weight change and feed conversion ratio of free-range village chickens was investigated. Food waste collected from 20 different restaurants of Universiti Putra Malaysia Serdang Selangor was processed into DPFW containing 89.3% dry matter, 16% crude protein, 7.1% crude fat, 3.7% crude fiber, 7.4% crude ash, 3.07% NaCl, 1.56% Ca, 0.87% phosphorous and 4053 kcal/kg GE. A total of of 180 village chickens of the Arabian breed were randomly allocated into four dietary treatments of 0 (control, 20, 40 and 60% DPFW for 5-9 week grower and 10-14 week finisher periods with three replicates (15 birds for each replicate. The results showed that the highest feed intake in grower and finisher phases was observed in the control group by 634.0 g and 2,722.1 g, respectively, while the lowest was in 60% DPFW with 586.3 g for grower and 2,542.6 g for finisher phases (P0.05. Body weight gain and body weight change declined linearly with increasing levels of DPFW of more than 20% in the village chicken diets during both grower and finisher rearing phases. FAR increased (P0.05. In conclusion it seems that the dehydrated processed food waste could substitute 20% of formulated feed in grower and finisher phases of free-range village chickens without any adverse effects on growth performance.

  13. Stabilization/solidification of hot dip galvanizing ash using different binders.

    Science.gov (United States)

    Vinter, S; Montanes, M T; Bednarik, V; Hrivnova, P

    2016-12-15

    This study focuses on solidification of hot dip-galvanizing ash with a high content of zinc and soluble substances. The main purpose of this paper is to immobilize these pollutants into a matrix and allow a safer way for landfill disposal of that waste. Three different binders (Portland cement, fly ash and coal fluidized-bed combustion ash) were used for the waste solidification. Effectiveness of the process was evaluated using leaching test according to EN 12457-4 and by using the variance analysis and the categorical multifactorial test. In the leaching test, four parameters were observed: pH, zinc concentration in leachate, and concentration of chlorides and dissolved substances in leachate. The acquired data was then processed using statistical software to find an optimal solidifying ratio of the addition of binder, water, and waste to the mixture, with the aim to fulfil the requirement for landfill disposal set by the Council Decision 2003/33/EC. The influence on the main observed parameters (relative amount of water and a binder) on the effectiveness of the used method and their influence of measured parameters was also studied. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory. Volume 2: Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste, as mandated by the Nuclear Waste Policy Act of 1982. The waste forms comprised about 700 metric tons of initial heavy metal (or equivalent units) stored at the INEL: graphite spent fuel, experimental low enriched and highly enriched spent fuel, and high-level waste generated during reprocessing of some spent fuel. Five different waste treatment options were studied; in the analysis, the options and resulting waste forms were analyzed separately and in combination as five waste disposal groups. When the waste forms were studied in combination, the repository was assumed to also contain vitrified high-level waste from three DOE sites for a common basis of comparison and to simulate the impact of the INEL waste forms on a moderate-sized repository, The performance of the waste form was assessed within the context of a whole disposal system, using the U.S. Environmental Protection Agency`s Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191, promulgated in 1985. Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories.

  15. Russia: results and prospects of liquid solidification experiments at ROSATOM sites

    Energy Technology Data Exchange (ETDEWEB)

    Pokhitonov, Y.; Babain, V.; Kamachev, V. [V.G. Khlopin Radium Inst., St. Petersburg (Russian Federation); Kelley, D. [Pacific Nuclear Solutions, Indianapolis, Indiana (United States)

    2011-07-01

    Ongoing experimental work has been underway at selected nuclear sites in the Russian State Atomic Energy Corporation (ROSATOM) during the past two years to determine the effectiveness, reliability, application and acceptability of high technology polymers for liquid radioactive waste solidification. The long term project is funded by the U.S. Department of Energy's Initiatives for Proliferation Prevention (IPP) program. IPP was established in 1994 as a non-proliferation program of DOE / National Nuclear Security Administration and receives its funding each year through Congressional appropriation. The objectives of IPP are: To engage former Soviet nuclear weapons scientists, engineers and technicians, currently or formerly involved with weapons of mass destruction, in peaceful and sustainable commercial activities; To identify non-military, commercial applications for former Soviet institute technologies through cooperative projects among former Soviet weapons scientists, U.S. national laboratories and U.S. industry; and, To create new technology sources and to provide business opportunities for U.S. companies, while offering commercial opportunities and meaningful employment for former weapons scientists. Argonne National Laboratory provides management oversight for this project. More than 60 former weapons scientists are engaged in this project. With the project moving toward its conclusion in 2012, the emphasis is now on expanding the experimental work to include the sub-sites of Seversk (SGCHE), Zheleznogorsk (GKhK) located in Siberia and Gatchyna (KRI) and applying the polymer technology to actual problematic waste streams as well as to evaluate the prospects for new applications, beyond their current use in the nuclear waste treatment field. Work to date includes over the solidification of over 100 waste streams for the purpose of evaluating all aspects of the polymer's effectiveness with LLW and ILW complex waste. Waste stream compositions include

  16. The use of new PHACOMP in understanding the solidification microstructure of nickel base alloy weld metal

    Science.gov (United States)

    Cieslak, M. J.; Knorovsky, G. A.; Headley, T. J.; Romig, A. D.

    1986-12-01

    The weld metal microstructures of five commercial nickel base alloys (HASTELLOYS* C-4, C-22, and C-276, and INCONELS* 625 and 718) have been examined by electron probe microanalysis and analytical electron microscopy. It has been found that solidification terminates in many of these alloys with the formation of a constituent containing a topologically-close-packed (TCP) intermetallic phase (i.e., σ, P, Laves). Electron microprobe examination of gas-tungsten-arc welds revealed a solidification segregation pattern of Ni depletion and solute enrichment in interdendritic volumes. New PHACOMP calculations performed on these segregation profiles revealed a pattern of increasing M d (metal- d levels) in traversing from a dendrite core to an adjacent interdendritic volume. In alloys forming a terminal solidification TCP constituent, the calculated M d values in interdendritic regions were greater than the critical M d values for formation of σ as stated by Morinaga et al. Implications of the correlation between TCP phase formation and M d in the prediction of weld metal solidification microstructure, prediction of potential hot-cracking behavior, and applications in future alloy design endeavors are discussed.

  17. Performance assessment for low-level waste disposal in the UK

    Energy Technology Data Exchange (ETDEWEB)

    Ashworth, A.B. [UK Dept. of the Environment, London (United Kingdom)

    1995-12-31

    British Nuclear Fuels plc (BNFL) operate a site for the disposal of Low Level Radioactive Waste at Drigg in West Cumbria, in North-West England. HMIP are responsible for the regulation of the site with regard to environmental discharges of radioactive materials, both operational and post-closure. This paper is concerned with post-closure matters only. Two post-closure performance assessments have been carried out for this site: one by the National Radiological Protection Board (NRPB) in 1987; and a subsequent one carried out on behalf of HMIP, completed in 1991. Currently, BNFL are preparing a Safety Case for continued operation of the Drigg site, and it expected that the core of this Case will comprise BNFL`s own analysis of post-closure performance. HMIP has developed procedures for the assessment of this Case, based upon experience of the previous Drigg assessments, and also upon the experience of similar work carried out in the assessment of Intermediate Level Waste (ILW) disposal at both deep and shallow potential sites. This paper describes the more important features of these procedures.

  18. Performance Assessment of a Low-Level Radioactive Waste Disposal Site using GoldSim Integrated Systems Model

    Science.gov (United States)

    Merrell, G.; Singh, A.; Tauxe, J.; Perona, R.; Dornsife, W.; grisak, G. E.; Holt, R. M.

    2011-12-01

    Texas Commission on Environmental Quality has approved licenses for four landfills at the Waste Control Specialists (WCS) site located in Andrews County, West Texas. The site includes a hazardous waste landfill and three landfills for radioactive waste. An updated performance assessment is necessary prior to acceptance of waste at the landfills. The updated performance assessment a) provides for more realistic and flexible dose modeling capabilities, b) addresses all plausible release and accident scenarios as they relate to the performance objectives, c) includes impact of climate and hydrologic scenarios that may impact long-term performance of the landfill, d) addresses impact of cover naturalization and degradation on the landfill, and e) incorporates uncertainty and sensitivity analysis for critical parameters. For the updated performance assessment, WCS has developed an integrated systems level performance assessment model using the GoldSim platform. GoldSim serves as a model for integrating all of the major components of a performance assessment, which include the radionuclide source term, facility design, environmental transport pathways, exposure scenarios, and radiological doses. Unlike many computer models that are based on first principles, GoldSim is a systems level model that can be used to integrate and abstract more complex sub-models into one system. This can then be used to assess the results into a unified model of the disposal system and environment. In this particular application, the GoldSim model consists of a) hydrogeologic model that simulates flow and transport through the Dockum geologic unit that underlies all of the waste facilities, b) waste cells that represent the containment unit and simulate degradation of waste forms, radionuclide leaching, and partitioning into the liquid and vapor phase within the waste unit, c) a cover system model that simulates upward diffusive transport from the underground repository to the atmosphere. In

  19. Waste Acceptance Testing of Secondary Waste Forms: Cast Stone, Ceramicrete and DuraLith

    Energy Technology Data Exchange (ETDEWEB)

    Mattigod, Shas V.; Westsik, Joseph H.; Chung, Chul-Woo; Lindberg, Michael J.; Parker, Kent E.

    2011-08-12

    To support the selection of a waste form for the liquid secondary wastes from WTP, Washington River Protection Solutions has initiated secondary-waste-form testing work at Pacific Northwest National Laboratory (PNNL). In anticipation of a down-selection process for a waste form for the Solidification Treatment Unit to be added to the ETF, PNNL is conducting tests on four candidate waste forms to evaluate their ability to meet potential waste acceptance criteria for immobilized secondary wastes that would be placed in the IDF. All three waste forms demonstrated compressive strengths above the minimum 3.45 MPa (500 psi) set as a target for cement-based waste forms. Further, none of the waste forms showed any significant degradation in compressive strength after undergoing thermal cycling (30 cycles in a 10 day period) between -40 C and 60 C or water immersion for 90 days. The three leach test methods are intended to measure the diffusion rates of contaminants from the waste forms. Results are reported in terms of diffusion coefficients and a leachability index (LI) calculated based on the diffusion coefficients. A smaller diffusion coefficient and a larger LI are desired. The NRC, in its Waste Form Technical Position (NRC 1991), provides recommendations and guidance regarding methods to demonstrate waste stability for land disposal of radioactive waste. Included is a recommendation to conduct leach tests using the ANS 16.1 method. The resulting leachability index (LI) should be greater than 6.0. For Hanford secondary wastes, the LI > 6.0 criterion applies to sodium leached from the waste form. For technetium and iodine, higher targets of LI > 9 for Tc and LI > 11 for iodine have been set based on early waste-disposal risk and performance assessment analyses. The results of these three leach tests conducted for a total time between 11days (ASTM C1308) to 90 days (ANS 16.1) showed: (1) Technetium diffusivity: ANSI/ANS 16.1, ASTM C1308, and EPA 1315 tests indicated that

  20. Final Project Report CFA-14-6357: A New Paradigm for Understanding Multiphase Ceramic Waste Form Performance

    Energy Technology Data Exchange (ETDEWEB)

    Brinkman, Kyle [Clemson Univ., SC (United States); Bordia, Rajendra [Clemson Univ., SC (United States); Reifsnider, Kenneth [Univ. of South Carolina, Columbia, SC (United States); Chiu, Wilson [Univ. of Connecticut, Storrs, CT (United States); Amoroso, Jake [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-12-28

    This project fabricated model multiphase ceramic waste forms with processing-controlled microstructures followed by advanced characterization with synchrotron and electron microscopy-based 3D tomography to provide elemental and chemical state-specific information resulting in compositional phase maps of ceramic composites. Details of 3D microstructural features were incorporated into computer-based simulations using durability data for individual constituent phases as inputs in order to predict the performance of multiphase waste forms with varying microstructure and phase connectivity.

  1. Combustion Analysis of a CI Engine Performance Using Waste Cooking Biodiesel Fuel with an Artificial Neural Network Aid

    OpenAIRE

    Najafi, Gholamhassan; Ghobadian, Barat; TALAL F. YUSAF; Hadi RAHIMI

    2007-01-01

    A comprehensive combustion analysis has been conducted to evaluate the performance of a commercial DI engine, water cooled two cylinders, in-line, naturally aspirated, RD270 Ruggerini diesel engine using waste vegetable cooking oil as an alternative fuel. In order to compare the brake power and the torques values of the engine, it has been tested under same operating conditions with diesel fuel and waste cooking biodiesel fuel blends. The results were found to be very comparable. The properti...

  2. Stabilization and solidification of electric arc furnace dust originating from steel industry by using low grade MgO

    Directory of Open Access Journals (Sweden)

    Bayraktar Ahmet Can

    2015-12-01

    Full Text Available In this study, solidification/stabilization (S/S of electric arc furnace dust (EAFD which is generated during the production of steel from scrap metals and classified as hazardous waste were investigated by using different ratios of cement and low grade MgO (LG MgO as binding agents. Type I PC 42.5 R portland cement and LG MgO which contains 70–80% MgO were used. S/S blocks that contain different ratios of binding agents which have 1/0.5 – 1/1 – 1/2 – 1/3 – 1/4 – 1/5 cement/LG MgO ratio and S/S blocks which contain only cement and no LG MgO agents were prepared. These blocks, which contain 3 different waste ratios according to weight, 20%, 30% and 40% respectively, were produced and exposed to 28-day water purification. At the end of the purification process, S/S blocks were extracted using TCLP (Toxicity Characteristic Leaching Procedure tests in order to determine the leaching behavior of Zn, Pb, and Cd in S/S blocks. By the end of this study, it was concluded that the recovery of EAFD is possible and applicable by immobilization. The findings of the study concluded that environmental performances or structural properties of blocks contain 30% waste by weight are suitable. This method is a proper one for recovering and treatment of EAFD with mixture of cement and LG MgO.

  3. Importance-performance analysis of municipal solid waste management in uncertainty.

    Science.gov (United States)

    Tseng, Ming-Lang

    2011-01-01

    The aim of this study was to evaluate and position the perceptions of importance and performance of municipal solid waste management aspects and criteria. The study results propose dependence relations among four aspects and 33 criteria pertaining to metropolitan Taipei. Evaluation was based on linguistically described preferences and multiple aspects and criteria analysis; in particular, applied fuzzy set theory was used to evaluate linguistic vagueness, and the analytic network process was applied for dependence relations among the aspects and criteria. In order to compile managerial implications and concluding remarks, importance-performance analysis was conducted, using several mathematical techniques applied to the objectives as well as the participation and input of professionals and academicians. Overall results and concluding remarks are discussed.

  4. Performance evaluation of the bioreactor landfill in treatment and stabilisation of mechanically biologically treated municipal solid waste.

    Science.gov (United States)

    Lakshmikanthan, P; Sivakumar Babu, G L

    2017-03-01

    The potential of bioreactor landfills to treat mechanically biologically treated municipal solid waste is analysed in this study. Developing countries like India and China have begun to investigate bioreactor landfills for municipal solid waste management. This article describes the impacts of leachate recirculation on waste stabilisation, landfill gas generation, leachate characteristics and long-term waste settlement. A small-scale and large-scale anaerobic cell were filled with mechanically biologically treated municipal solid waste collected from a landfill site at the outskirts of Bangalore, India. Leachate collected from the same landfill site was recirculated at the rate of 2-5 times a month on a regular basis for 370 days. The total quantity of gas generated was around 416 L in the large-scale reactor and 21 L in the small-scale reactor, respectively. Differential settlements ranging from 20%-26% were observed at two different locations in the large reactor, whereas 30% of settlement was observed in the small reactor. The biological oxygen demand/chemical oxygen demand (COD) ratio indicated that the waste in the large reactor was stabilised at the end of 1 year. The performance of the bioreactor with respect to the reactor size, temperature, landfill gas and leachate quality was analysed and it was found that the bioreactor landfill is efficient in the treatment and stabilising of mechanically biologically treated municipal solid waste.

  5. Performance-assessment comparisons for a repository containing LWR spent fuel or partitioned/transmutted nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, R.W. [Sandia National Lab., System Performance Assessment, Division 6312, Albuquerque, NM (US); Lee, W.W.L. [Univ. of California, Lawrence Berkeley Lab., Earth Sciences Div., Berkeley, CA (US)

    1992-11-01

    This paper describes one component of the total-system performance assessment analyses being performed for a potential geologic repository containing partitioned and/or transmuted waste. An analysis of the releases of radionuclides at the earth`s surface due to human intrusion is presented here. The results are compared with other total-system performance assessments for the potential Yucca Mountain repository containing light-water-reactor spent fuel. Although most of the releases from a repository containing partitioned/transmuted waste are lower than those from a repository containing conventional spent fuel, the maximum releases are not significantly different.

  6. Performance-assessment comparisons for a repository containing LWR spent fuel or partitioned/transmuted nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, R.W. (Sandia National Labs., Albuquerque, NM (United States)); Lee, W.W.L. (Lawrence Berkeley Lab., CA (United States))

    1992-01-01

    This paper describes one component of the total-system performance assessment analyses being performed for a potential geologic repository containing partitioned and/or transmuted waste. An analysis of the releases of radionuclides at the earth's surface due to human intrusion is presented here. The results are compared with other total-system performance assessments for the potential Yucca Mountain repository containing light-water-reactor spent fuel. Although most of the releases from a repository containing partitioned/transmuted waste are lower than those from a repository containing conventional spent fuel, the maximum releases are not significantly different.

  7. Performance-assessment comparisons for a repository containing LWR spent fuel or partitioned/transmuted nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, R.W. [Sandia National Labs., Albuquerque, NM (United States); Lee, W.W.L. [Lawrence Berkeley Lab., CA (United States)

    1992-01-01

    This paper describes one component of the total-system performance assessment analyses being performed for a potential geologic repository containing partitioned and/or transmuted waste. An analysis of the releases of radionuclides at the earth`s surface due to human intrusion is presented here. The results are compared with other total-system performance assessments for the potential Yucca Mountain repository containing light-water-reactor spent fuel. Although most of the releases from a repository containing partitioned/transmuted waste are lower than those from a repository containing conventional spent fuel, the maximum releases are not significantly different.

  8. Development of performance assessment methodology for establishment of quantitative acceptance criteria of near-surface radioactive waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Kim, C. R.; Lee, E. Y.; Park, J. W.; Chang, G. M.; Park, H. Y.; Yeom, Y. S. [Korea Hydro and Nuclear Power Co., Ltd., Seoul (Korea, Republic of)

    2002-03-15

    The contents and the scope of this study are as follows : review of state-of-the-art on the establishment of waste acceptance criteria in foreign near-surface radioactive waste disposal facilities, investigation of radiological assessment methodologies and scenarios, investigation of existing models and computer codes used in performance/safety assessment, development of a performance assessment methodology(draft) to derive quantitatively radionuclide acceptance criteria of domestic near-surface disposal facility, preliminary performance/safety assessment in accordance with the developed methodology.

  9. Influence of gravity on the solidification of a drop

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, A.; Meseguer, J.; Mayo, L.

    1987-03-01

    In this paper the influence of gravity on the solidification of a drop formed at the end of a rod is analyzed. Although similar studies (but ignoring gravity effects) already exist, a theoretical analysis including gravity effects allows one to improve the experimental procedure to measure on Earth relevant properties of crystals (mainly the receding contact angle phi/sub i/) which are of importance in shaped crystal growth processes. One of the main results here obtained are the shapes of the solidified drops, which are strongly dependent on the value of phi/sub i/. Therefore, fitting theoretical shapes to experimental ones is a way to perform accurate measurements of phi/sub i/.

  10. Finite Element Modelling Of Solidification Of Zinc Alloy | Osinkolu ...

    African Journals Online (AJOL)

    The solidification process of Zinc alloy is modelled by solving heat transfer equations with the aid of finite element method (FEM) using appropriate boundary conditions at the mould walls. The commercial software, Matlab, has been used to model the solidification process. The temperature profiles for each casting condition ...

  11. Study on Combustion Performance of Diesel Engine Fueled by Synthesized Waste Cooking Oil Biodiesel Blends

    Directory of Open Access Journals (Sweden)

    Duraid F. Maki

    2018-02-01

    Full Text Available The waste cooking oil or used cooking oil is the best source of biodiesel synthesizing because it enters into the so-called W2E field whereas not only get rid of the used cooking oils but produce energy from waste fuel. In this study, biodiesel was synthesized from the used cooking oil and specifications are tested. From 1 liter of used cooking oil, 940 ml is gained. The remaining of liter is glycerin and water. Blend of 20% of biodiesel with 80% of net diesel by volume is formed. Blends of 100% diesel and 100% biodiesel are prepared too. The diesel engine combustion performance is studied. Brake thermal efficiency, brake specific fuel consumption, volumetric efficiency, mean effective pressure, and engine outlet temperature. Cylinder pressure variation with crank angle is analyzed. At last not least, the concentrations of hydro carbon and nitrogen pollutants are measured. The results showed significant enhancement in engine power and pollutant gases emitted. There is positive compatible with other critical researches.

  12. Performance and emission study on waste cooking oil biodiesel and distillate blends for microturbine application

    Directory of Open Access Journals (Sweden)

    Ee Sann Tan

    2015-11-01

    Full Text Available Biodiesel is defined as domestic renewable energy resource, which can be derived from natural oils through the transesterification. The implementation of biodiesel is essential due to the energy depletion crisis and the impact on exacerbating environment caused by rapid consumption of conventional diesel. Waste cooking oil (WCO was used as the raw material to produce biodiesel in order to reduce wastes polluting the environment. This paper studies the technical potential of WCO biodiesel to be used as an alternative fuel for microturbine. The ASTM D6751 and ASTM D2881 standards were selected as references to evaluate the compatibility with distillate to be used as a microturbine fuel. The performance and emission tests were conducted employing a 30 kW microturbine, without any modification, using biodiesel and distillate blends up to maximum of 20% biodiesel mixing ratio. It was found that the thermal efficiency peaked at 20% biodiesel blend with distillate, despite the fact that biodiesel had a lower calorific value and a higher fuel consumption. The emission test results showed reduction of CO emission by increasing the WCO biodiesel mixing ratio, while NOx emission was dependent on the exhaust gas temperature. In conclusion, biodiesel derived from WCO has the potential to substitute distillate in the microturbine application.

  13. Investigations of subterranean microorganisms. Their importance for performance assessment of radioactive waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, K. [Goeteborg Univ. (Sweden). General and Marine Microbiology; Karlsson, Fred [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    1995-06-01

    This report presents a broad and thorough description of how microorganisms may influence safety of repositories for radioactive waste. First, an overview of the Swedish concepts for disposal is given, including a discussion of the geological, chemical and hydrological conditions in repositories. Then the limiting and stimulating factors for life of microorganisms are reviewed, such as relations to oxygen, temperature, pH, radiation, pressure, water and nutrients availability. Bacteria in the cycles of carbon, nitrogen, sulfur, iron, manganese and hydrogen are also discussed. A literature review of subterranean bacteria is given in chapter 4. Chapter 5 treats investigations of microorganisms in repository-like environments, and microbial corrosion and redox processes relevant for materials in the repository and for the mobility of radionuclides. Possibilities to predict the activity and presence of microorganisms through mathematical models are discussed in chapter 6. Chapter 7 summarizes the conclusion drawn in the report, how microorganisms may influence performance safety assessment of radioactive waste disposal, and also identifies research needs. 293 refs, 43 figs, 36 tabs.

  14. Development of performance indicators for municipal solid waste management (PIMS): A review.

    Science.gov (United States)

    Sanjeevi, V; Shahabudeen, P

    2015-12-01

    The aim of this paper is to review papers on municipal solid waste management (SWM) systems, especially on performance indicators (PIs), and suggest practical methods to manage the same by administrators. Worldwide, about 4 billion metric tons of solid waste (SW) is generated annually; the management of SW across cities is increasingly getting more complex and the funds available for providing service to citizens are shrinking. Analysis of the non-technical research papers shows that focus areas on SW can be grouped into 18 types, one being PIs. Historically, PIs for municipal SWM (PIMS) commenced with the publication of guidelines by various government agencies, starting in 1969. This was followed by a few benchmarking studies, commencing in 1998, by various international institutions. Many published comparative studies also disseminated good practices across the cities. From the 1990s onwards, research work started defining PIMS. These initiatives by various researchers took multiple dimensions and are reviewed in this paper. In almost all studies, the PIMS is measured in terms of investment decisions, public acceptance levels, social participation and environmental needs. The multiple indicators are complex, however, and managers of cities need simple tools to use. To make it simple, five-factor PIs are arrived at, considering simplicity and covering all the factors. A research agenda is outlined for future directions in the areas of cost reduction, citizens' services, citizen involvement and environmental impact. © The Author(s) 2015.

  15. Co-digestion performance of organic fraction of municipal solid waste with leachate: Preliminary studies.

    Science.gov (United States)

    Guven, Huseyin; Akca, Mehmet Sadik; Iren, Erol; Keles, Fatih; Ozturk, Izzet; Altinbas, Mahmut

    2017-05-04

    The main aim of the study was to evaluate the co-digestion performance of OFMSW with different wastes. Leachate, reverse osmosis (RO) concentrate collected from a leachate treatment facility and dewatered sewage sludge taken from a wastewater treatment plant (WWTP) were used for co-digestion in this paper. An extra effort was made to observe the effect of leachate inclusion in the co-digestion. In the study, the mono-digestion of OFMSW, leachate, RO concentrate and sewage sludge as well as digestion of 7 different waste mixtures were carried out for this objective. The experiments were carried out for approximately 50days under mesophilic conditions. The highest methane yield was 785L CH4/kg VSadded in the reactor, which had only OFMSW. While the methane yield derived from OFMSW was found higher than previous studies, methane yield of leachate was found to be 110L CH4/kg VSadded, which was lower than findings in the literature. The mono-substrate of OFMSW was followed by the reactor of having waste mixture of leachate+sewage sludge+OFMSW+water (C7) with 391L CH4/kg VSadded, which was the only combination included water. In order to understand the effect of leachate and water inclusions on co-digestion, two separate waste combinations; leachate+sewage sludge+OFMSW+water (C7) and leachate+sewage sludge+OFMSW (C1) were prepared that had different amounts of leachate but same amounts of other wastes. The methane yield of leachate+sewage sludge+OFMSW+water (C7) indicated that addition of some water instead of leachate could stimulate biogas production. Methane yield of this reactor was found to be 71% higher than the waste combination of leachate+sewage sludge+OFMSW (C1). It could be thought that the high amount of non-biodegradable matters in leachate could be responsible for lower methane yield in leachate+sewage sludge+OFMSW (C1) reactor. Methane yields of the reactors showed that co-digestion of OFMSW and leachate could be a solution not only for treatment of

  16. Product acceptance of a certified Class C low-level waste form at the West Valley Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Valenti, P.J. [West Valley Nuclear Services Co., Inc., NY (United States); Maestas, E.; Yeazel, J.A. [Dept. of Energy, West Valley, NY (United States). West Valley Project Office; McIntosh, T.W. [Dept. of Energy, Washington, DC (United States). Office of Remedial Action and Waste Technology

    1989-11-01

    The Department of Energy, is charged with the solidification of high-level liquid waste (HLW) remaining from nuclear fuel reprocessing activities, which were conducted at West Valley, New York between 1966 and 1972. One important aspect of the West Valley Demonstration Project`s fully integrated waste program is the treatment and conditioning of low-level wastes which result from processing liquid high-level waste. The treatment takes place in the project`s Integrated Radwaste Treatment System which removes Cesium-137 from the liquid or supernatant phase of the HLW by utilizing an ion exchange technique. The resulting decontaminated and conditioned liquid waste stream is solidified into a Class C low-level cement waste form that meets the waste form criteria specified in NRC 10 CFR 61. The waste matrix is placed in 71-gallon square drums, remotely handled and stored on site until determination of final disposition. This paper discusses the programs in place at West Valley to ensure production of an acceptable cement-based product. Topics include the short and long term test programs to predict product storage and disposal performance, description of the Process Control Plan utilized to control and maintain cement waste form product specifications and finally discuss the operational performance characteristics of the Integrated Radwaste Treatment System. Operational data and product statistics are provided.

  17. Synthesis and Performance Evaluation of a New Deoiling Agent for Treatment of Waste Oil-Based Drilling Fluids

    Directory of Open Access Journals (Sweden)

    Pingting Liu

    2014-01-01

    Full Text Available Oil-based drilling fluid is used more and more in the field of oil and gas exploration. However, because of unrecyclable treating agent and hard treatment conditions, the traditional treating technologies of waste oil-based drilling fluid have some defects, such as waste of resource, bulky equipment, complex treatment processes, and low oil recovery rate. In this work, switchable deoiling agent (SDA, as a novel surfactant for treatment of waste oil-based drilling fluid, was synthesized by amine, formic acid, and formaldehyde solution. With this agent, the waste oil-based drilling fluid can be treated without complex process and expensive equipment. Furthermore, the agent used in the treatment can be recycled, which reduces waste of resource and energy. The switch performance, deoiling performance, structural characterization, and mechanisms of action are studied. The experimental results show that the oil content of the recycled oil is higher than 96% and more than 93% oil in waste oil-based drilling fluid can be recycled. The oil content of the solid residues of deoiling is less than 3%.

  18. Synthesis and performance evaluation of a new deoiling agent for treatment of waste oil-based drilling fluids.

    Science.gov (United States)

    Liu, Pingting; Huang, Zhiyu; Deng, Hao; Wang, Rongsha; Xie, Shuixiang

    2014-01-01

    Oil-based drilling fluid is used more and more in the field of oil and gas exploration. However, because of unrecyclable treating agent and hard treatment conditions, the traditional treating technologies of waste oil-based drilling fluid have some defects, such as waste of resource, bulky equipment, complex treatment processes, and low oil recovery rate. In this work, switchable deoiling agent (SDA), as a novel surfactant for treatment of waste oil-based drilling fluid, was synthesized by amine, formic acid, and formaldehyde solution. With this agent, the waste oil-based drilling fluid can be treated without complex process and expensive equipment. Furthermore, the agent used in the treatment can be recycled, which reduces waste of resource and energy. The switch performance, deoiling performance, structural characterization, and mechanisms of action are studied. The experimental results show that the oil content of the recycled oil is higher than 96% and more than 93% oil in waste oil-based drilling fluid can be recycled. The oil content of the solid residues of deoiling is less than 3%.

  19. Performance assessment for the disposal of low-level waste in the 200 east area burial grounds

    Energy Technology Data Exchange (ETDEWEB)

    Wood, M.I., Westinghouse Hanford

    1996-08-15

    A performance assessment analysis was completed for the 200 East Area Low-Level Burial Grounds (LLBG) to satisfy compliance requirements in DOE Order 5820.2A. In the analysis, scenarios of radionuclide release from the 200 East Area Low-Level waste facility was evaluated. The analysis focused on two primary scenarios leading to exposure. The first was inadvertent intrusion. In this scenario, it was assumed that institutional control of the site and knowledge of the disposal facility has been lost. Waste is subsequently exhumed and dose from exposure is received. The second scenario was groundwater contamination.In this scenario, radionuclides are leached from the waste by infiltrating precipitation and transported through the soil column to the underlying unconfined aquifer. The contaminated water is pumped from a well 100 m downstream and consumed,causing dose. Estimates of potential contamination of the surrounding environment were developed and the associated doses to the maximum exposed individual were calculated. The doses were compared with performance objective dose limits, found primarily in the DOE order 5850.2A. In the 200 East Area LLBG,it was shown that projected doses are estimated to be well below the limits because of the combination of environmental, waste inventory, and disposal facility characteristics of the 200 East Area LLBG. Waste acceptance criteria were also derived to ensure that disposal of future waste inventories in the 200 East Area LLBG will not cause an unacceptable increase in estimated dose.

  20. Performance evaluation of restaurant food waste and biowaste to biogas pilot projects in China and implications for national policy.

    Science.gov (United States)

    De Clercq, Djavan; Wen, Zongguo; Fan, Fei

    2017-03-15

    The objective of this research was to conduct a performance evaluation of three food waste/biowaste-to-biogas pilot projects across 7 scenarios in China based on multi-criteria decision analysis (MCDA) methodology. The projects ranked included a food waste-biogas project in Beijing, a food waste-biogas project in Suzhou and a co-digestion project producing biomethane in Hainan. The projects were ranked from best to worst based on technical, economic and environmental criteria under the MCDA framework. The results demonstrated that some projects are encountering operational problems. Based on these findings, six national policy recommendations were provided: (1) shift away from capital investment subsidies to performance-based subsidies; (2) re-design feed in tariffs; (3) promote bio-methane and project clustering; (4) improve collection efficiency by incentivizing FW producers to direct waste to biogas projects; (5) incentivize biogas projects to produce multiple outputs; (6) incentivize food waste-based projects to co-digest food waste with other substrates for higher gas output. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Statements of work for FY 1996 to 2001 for the Hanford Low-Level Tank Waste Performance Assessment Project

    Energy Technology Data Exchange (ETDEWEB)

    Mann, F.M.

    1995-06-07

    The statements of work for each activity and task of the Hanford Low-Level Tank Waste Performance Assessment project are given for the fiscal years 1996 through 2001. The end product of this program is approval of a final performance assessment by the Department of Energy in the year 2000.

  2. Geochemical data package for the Hanford immobilized low-activity tank waste performance assessment (ILAW PA)

    Energy Technology Data Exchange (ETDEWEB)

    DI Kaplan; RJ Serne

    2000-02-24

    Lockheed Martin Hanford Company (LMHC) is designing and assessing the performance of disposal facilities to receive radioactive wastes that are stored in single- and double-shell tanks at the Hanford Site. The preferred method of disposing of the portion that is classified as low-activity waste is to vitrify the liquid/slurry and place the solid product in near-surface, shallow-land burial facilities. The LMHC project to assess the performance of these disposal facilities is the Hanford Immobilized Low-Activity Tank Waste (ILAW) Performance Assessment (PA) activity. The goal of this project is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface-water resources, and inadvertent intruders. Achieving this goal will require prediction of contaminant migration from the facilities. This migration is expected to occur primarily via the movement of water through the facilities, and the consequent transport of dissolved contaminants in the porewater of the vadose zone. Pacific Northwest National Laboratory assists LMHC in their performance assessment activities. One of the PNNL tasks is to provide estimates of the geochemical properties of the materials comprising the disposal facility, the disturbed region around the facility, and the physically undisturbed sediments below the facility (including the vadose zone sediments and the aquifer sediments in the upper unconfined aquifer). The geochemical properties are expressed as parameters that quantify the adsorption of contaminants and the solubility constraints that might apply for those contaminants that may exceed solubility constraints. The common parameters used to quantify adsorption and solubility are the distribution coefficient (K{sub d}) and the thermodynamic solubility product (K{sub sp}), respectively. In this data package, the authors approximate the solubility of contaminants using a more simplified construct

  3. Lab-scale co-digestion of kitchen waste and brown water for a preliminary performance evaluation of a decentralized waste and wastewater management.

    Science.gov (United States)

    Lavagnolo, Maria Cristina; Girotto, Francesca; Hirata, Osamu; Cossu, Raffaello

    2017-08-01

    An overall interaction is manifested between wastewater and solid waste management schemes. At the Laboratory of Environmental Engineering (LISA) of the University of Padova, Italy, the scientific and technical implications of putting into practice a decentralized waste and wastewater treatment based on the separation of grey water, brown water (BW - faecal matter) and yellow water (YW - urine) are currently undergoing investigation in the Aquanova Project. An additional aim of this concept is the source segregation of kitchen waste (KW) for subsequent anaerobic co-digestion with BW. To determine an optimal mixing ratio and temperature for use in the treatment of KW, BW, and eventually YW, by means of anaerobic digestion, a series of lab-scale batch tests were performed. Organic mixtures of KW and BW performed much better (max. 520mlCH 4 /gVS) in terms of methane yields than the individual substrates alone (max. 220mlCH 4 /gVS). A small concentration of urine proved to have a positive effect on anaerobic digestion performance, possibly due to the presence of micronutrients in YW. When considering high YW concentrations in the anaerobically digested mixtures, no ammonia inhibition was observed until a 30% and 10% YW content was added under mesophilic and thermophilic conditions, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Sandia National Laboratories performance assessment methodology for long-term environmental programs : the history of nuclear waste management.

    Energy Technology Data Exchange (ETDEWEB)

    Marietta, Melvin Gary; Anderson, D. Richard; Bonano, Evaristo J.; Meacham, Paul Gregory (Raytheon Ktech, Albuquerque, NM)

    2011-11-01

    Sandia National Laboratories (SNL) is the world leader in the development of the detailed science underpinning the application of a probabilistic risk assessment methodology, referred to in this report as performance assessment (PA), for (1) understanding and forecasting the long-term behavior of a radioactive waste disposal system, (2) estimating the ability of the disposal system and its various components to isolate the waste, (3) developing regulations, (4) implementing programs to estimate the safety that the system can afford to individuals and to the environment, and (5) demonstrating compliance with the attendant regulatory requirements. This report documents the evolution of the SNL PA methodology from inception in the mid-1970s, summarizing major SNL PA applications including: the Subseabed Disposal Project PAs for high-level radioactive waste; the Waste Isolation Pilot Plant PAs for disposal of defense transuranic waste; the Yucca Mountain Project total system PAs for deep geologic disposal of spent nuclear fuel and high-level radioactive waste; PAs for the Greater Confinement Borehole Disposal boreholes at the Nevada National Security Site; and PA evaluations for disposal of high-level wastes and Department of Energy spent nuclear fuels stored at Idaho National Laboratory. In addition, the report summarizes smaller PA programs for long-term cover systems implemented for the Monticello, Utah, mill-tailings repository; a PA for the SNL Mixed Waste Landfill in support of environmental restoration; PA support for radioactive waste management efforts in Egypt, Iraq, and Taiwan; and, most recently, PAs for analysis of alternative high-level radioactive waste disposal strategies including repositories deep borehole disposal and geologic repositories in shale and granite. Finally, this report summarizes the extension of the PA methodology for radioactive waste disposal toward development of an enhanced PA system for carbon sequestration and storage systems

  5. Carburizer Effect on Cast Iron Solidification

    Science.gov (United States)

    Janerka, Krzysztof; Kondracki, Marcin; Jezierski, Jan; Szajnar, Jan; Stawarz, Marcin

    2014-06-01

    This paper presents the effect of carburizing materials on cast iron solidification and crystallization. The studies consisted of cast iron preparation from steel scrap and different carburizers. For a comparison, pig iron was exclusively used in a solid charge. Crystallization analysis revealed the influence of the carburizer material on the crystallization curves as well as differences in the solidification paths of cast iron prepared with the use of different charge materials. The carburizers' influence on undercooling during the eutectic crystallization process was analyzed. The lowest undercooling rate was recorded for the melt with pig iron, then for synthetic graphite, natural graphite, anthracite, and petroleum coke (the highest undercooling rate). So a hypothesis was formulated that eutectic cells are created most effectively with the presence of carbon from pig iron (the highest nucleation potential), and then for the graphite materials (crystallographic similarity with the carbon precipitation in the cast iron). The most difficult eutectic crystallization is for anthracite and petroleum coke (higher undercooling is necessary). This knowledge can be crucial when the foundry plant is going to change the solid charge composition replacing the pig iron by steel scrap and the recarburization process.

  6. Solidification microstructures: Recent developments, future directions

    Energy Technology Data Exchange (ETDEWEB)

    Boettinger, W.J.; Coriell, S.R.; Greer, A.L.; Karma, A.; Kurz, W.; Rappaz, M.; Trivedi, R.

    2000-01-01

    The status of solidification science is critically evaluated and future directions of research in this technologically important area are proposed. The most important advances in solidification science and technology of the last decade are discussed: interface dynamics, phase selection, microstructure selection, peritectic growth, convection effects, multicomponent alloys, and numerical techniques. It is shown how the advent of new mathematical techniques (especially phase-field and cellular automata models) coupled with powerful computers now allows the following: modeling of complicated interface morphologies, taking into account not only steady state but also non-steady state phenomena; considering real alloys consisting of many elements through on-line use of large thermodynamic data banks; and taking into account natural and forced convection effects. A series of open questions and future prospects are also given. It is hoped that the reader is encouraged to explore this important and highly interesting field and to add her/his contributions to an ever better understanding and modeling of microstructure development.

  7. Geologic Data Package for 2001 Immobilized Low-Activity Waste Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    SP Reidel; DG Horton

    1999-12-21

    This database is a compilation of existing geologic data from both the existing and new immobilized low-activity waste disposal sites for use in the 2001 Performance Assessment. Data were compiled from both surface and subsurface geologic sources. Large-scale surface geologic maps, previously published, cover the entire 200-East Area and the disposal sites. Subsurface information consists of drilling and geophysical logs from nearby boreholes and stored sediment samples. Numerous published geological reports are available that describe the subsurface geology of the area. Site-specific subsurface data are summarized in tables and profiles in this document. Uncertainty in data is mainly restricted to borehole information. Variations in sampling and drilling techniques present some correlation uncertainties across the sites. A greater degree of uncertainty exists on the new site because of restricted borehole coverage. There is some uncertainty to the location and orientation of elastic dikes across the sites.

  8. JNC thermodynamic database for performance assessment of high-level radioactive waste disposal system

    Energy Technology Data Exchange (ETDEWEB)

    Yui, Mikazu; Azuma, Jiro; Shibata, Masahiro [Japan Nuclear Cycle Development Inst., Tokai Works, Waste Isolation Research Division, Tokai, Ibaraki (Japan)

    1999-11-01

    This report is a summary of status, frozen datasets, and future tasks of the JNC (Japan Nuclear Cycle Development Institute) thermodynamic database (JNC-TDB) for assessing performance of high-level radioactive waste in geological environments. The JNC-TDB development was carried out after the first progress report on geological disposal research in Japan (H-3). In the development, thermodynamic data (equilibrium constants at 25degC, I=0) for important radioactive elements were selected/determined based on original experimental data using different models (e.g., SIT, Pitzer). As a result, the reliability and traceability of the data for most of the important elements were improved over those of the PNC-TDB used in H-3 report. For detailed information of data analysis and selections for each element, see the JNC technical reports listed in this document. (author)

  9. The Hydrological Performance of Lightweight Green Roofs Made From Recycled Waste Materials As the Drainage Layer

    Directory of Open Access Journals (Sweden)

    Afizah Asman Nurul Shahadahtul

    2017-01-01

    Full Text Available Green roofs can be used for promoting infiltration and provide temporary storage spaces. Hence, in urban stormwater structural design, the investigation of the hydrological performance investigation is often required. Thus, this paper presents the results of a hydrological investigation in term of peak flow reduction and green roof’s weight using 0, 2, and 6% slope for three specimens drainage layer in green roofs. Three types of recycled waste are selected for each test bed which is rubber crumbs, palm oil shell, and polyfoam. Another test bed without a drainage layer as a control. The result indicates that rubber crumbs can be used as a stormwater control and runoff reduction while ensuring a good drainage and aeration of the substrate and roofs. From the results obtained shows that rubber crumbs are suitable as a drainage layer and a proposed slope of 6% are suitable for lightweight green roofs.

  10. Nuclear Energy Advanced Modeling and Simulation (NEAMS) waste Integrated Performance and Safety Codes (IPSC) : gap analysis for high fidelity and performance assessment code development.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joon H.; Siegel, Malcolm Dean; Arguello, Jose Guadalupe, Jr.; Webb, Stephen Walter; Dewers, Thomas A.; Mariner, Paul E.; Edwards, Harold Carter; Fuller, Timothy J.; Freeze, Geoffrey A.; Jove-Colon, Carlos F.; Wang, Yifeng

    2011-03-01

    This report describes a gap analysis performed in the process of developing the Waste Integrated Performance and Safety Codes (IPSC) in support of the U.S. Department of Energy (DOE) Office of Nuclear Energy Advanced Modeling and Simulation (NEAMS) Campaign. The goal of the Waste IPSC is to develop an integrated suite of computational modeling and simulation capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive waste storage or disposal system. The Waste IPSC will provide this simulation capability (1) for a range of disposal concepts, waste form types, engineered repository designs, and geologic settings, (2) for a range of time scales and distances, (3) with appropriate consideration of the inherent uncertainties, and (4) in accordance with rigorous verification, validation, and software quality requirements. The gap analyses documented in this report were are performed during an initial gap analysis to identify candidate codes and tools to support the development and integration of the Waste IPSC, and during follow-on activities that delved into more detailed assessments of the various codes that were acquired, studied, and tested. The current Waste IPSC strategy is to acquire and integrate the necessary Waste IPSC capabilities wherever feasible, and develop only those capabilities that cannot be acquired or suitably integrated, verified, or validated. The gap analysis indicates that significant capabilities may already exist in the existing THC codes although there is no single code able to fully account for all physical and chemical processes involved in a waste disposal system. Large gaps exist in modeling chemical processes and their couplings with other processes. The coupling of chemical processes with flow transport and mechanical deformation remains challenging. The data for extreme environments (e.g., for elevated temperature and high ionic strength media) that are

  11. Performance Analysis of Thermoelectric Based Automotive Waste Heat Recovery System with Nanofluid Coolant

    Directory of Open Access Journals (Sweden)

    Zhi Li

    2017-09-01

    Full Text Available Output performance of a thermoelectric-based automotive waste heat recovery system with a nanofluid coolant is analyzed in this study. Comparison between Cu-Ethylene glycol (Cu-EG nanofluid coolant and ethylene glycol with water (EG-W coolant under equal mass flow rate indicates that Cu-EG nanofluid as a coolant can effectively improve power output and thermoelectric conversion efficiency for the system. Power output enhancement for a 3% concentration of nanofluid is 2.5–8 W (12.65–13.95% compared to EG-Water when inlet temperature of exhaust varies within 500–710 K. The increase of nanofluid concentration within a realizable range (6% has positive effect on output performance of the system. Study on the relationship between total area of thermoelectric modules (TEMs and output performance of the system indicates that optimal total area of TEMs exists for maximizing output performance of the system. Cu-EG nanofluid as coolant can decrease optimal total area of TEMs compared with EG-W, which will bring significant advantages for the optimization and arrangement of TEMs whether the system space is sufficient or not. Moreover, power output enhancement under Cu-EG nanofluid coolant is larger than that of EG-W coolant due to the increase of hot side heat transfer coefficient of TEMs.

  12. Thermo-Economic Performance Analysis of a Regenerative Superheating Organic Rankine Cycle for Waste Heat Recovery

    Directory of Open Access Journals (Sweden)

    Zhonghe Han

    2017-10-01

    Full Text Available The Organic Rankine Cycle (ORC is a promising form of technology for recovering low-grade waste heat. In this study, a regenerative ORC system is established to recover the waste flue gas of 160 °C. Focusing on thermodynamic and economic performance while simultaneously considering the limitations of volume flow ratio (VFR and the effect of superheat, working fluid selection and parameter optimization have been investigated. The optimization of the evaporation temperature is carried out by analyzing the variation of net power output and specific investment cost (SIC. Then, the net power output, specific net power output, total exergy destruction rate, VFR, total capital cost, and levelized electricity cost (LEC are selected as criteria, and a fuzzy multi-criteria evaluation method is adopted to select a more suitable working fluid and determine the optimal degree of superheat. In addition, the preheating coefficient, latent heat coefficient, superheating coefficient, and internal heat coefficient were proposed to explore the effect of working fluid critical temperature on thermal efficiency. Research studies demonstrate that there is an optimal evaporation temperature, maximizing net power output and minimizing the SIC. Isohexane and butane have greater specific net power output due to greater latent heat. A suitable degree of superheat is not only conducive to improving the working capacity of working fluids, but also reduces the VFR, total capital cost, SIC, and LEC for different working fluids. Thus, the system’s thermodynamic and economic performance—as well as the operational stability—are improved. Among the six working fluids, butane exhibits the best comprehensive performance, and its optimal evaporation temperature and degree of superheat are 100 °C and 5 °C, respectively.

  13. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory. Volume 1, Methodology and results

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste. Although numerous caveats must be placed on the results, the general findings were as follows: Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories.

  14. Radionuclide Retention Mechanisms in Secondary Waste-Form Testing: Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Um, Wooyong; Valenta, Michelle M.; Chung, Chul-Woo; Yang, Jungseok; Engelhard, Mark H.; Serne, R. Jeffrey; Parker, Kent E.; Wang, Guohui; Cantrell, Kirk J.; Westsik, Joseph H.

    2011-09-26

    This report describes the results from laboratory tests performed at Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions (WRPS) to evaluate candidate stabilization technologies that have the potential to successfully treat liquid secondary waste stream effluents produced by the Hanford Tank Waste Treatment and Immobilization Plant (WTP). WRPS is considering the design and construction of a Solidification Treatment Unit (STU) for the Effluent Treatment Facility (ETF) at Hanford. The ETF, a multi-waste, treatment-and-storage unit that has been permitted under the Resource Conservation and Recovery Act (RCRA), can accept dangerous, low-level, and mixed wastewaters for treatment. The STU needs to be operational by 2018 to receive secondary liquid waste generated during operation of the WTP. The STU will provide the additional capacity needed for ETF to process the increased volume of secondary waste expected to be produced by WTP. This report on radionuclide retention mechanisms describes the testing and characterization results that improve understanding of radionuclide retention mechanisms, especially for pertechnetate, {sup 99}TcO{sub 4}{sup -} in four different waste forms: Cast Stone, DuraLith alkali aluminosilicate geopolymer, encapsulated fluidized bed steam reforming (FBSR) product, and Ceramicrete phosphate bonded ceramic. These data and results will be used to fill existing data gaps on the candidate technologies to support a decision-making process that will identify a subset of the candidate waste forms that are most promising and should undergo further performance testing.

  15. The effect of adding boron in solidification microstructure of dilute iron-carbon alloy as assessed by phase-field modeling

    Directory of Open Access Journals (Sweden)

    Henrique Silva Furtado

    2011-01-01

    Full Text Available Alloying element like boron, even in small addition, is well known to improve hardenability of steels. Its application can improve mechanical properties of steels and reduce alloying costs. Despite these benefits is not easy to cast boron steels, mainly in dynamical solidification process like continuous casting, due to their crack susceptibility1,2. The strategy of using Phase-Field simulation of the solidification process is based on its proved capacity of predicting realistic microstructure that emerge during solidification under conditions even far from equilibrium3-5. Base on this, some comparative simulations were performed using a three component dilute alloy in a two dimensional domain under unconstrained (isothermal and constrained (directional solidification. Simulation results suggested two fragile mechanisms: one related to a deep dendritic primary arms space and other due to the remelting of this region at low temperature. Both resulted mainly from the high boron segregation in interdendritic regions.

  16. Tapped density optimisation for four agricultural wastes - Part II: Performance analysis and Taguchi-Pareto

    Directory of Open Access Journals (Sweden)

    Ajibade Oluwaseyi Ayodele

    2016-01-01

    Full Text Available In this attempt, which is a second part of discussions on tapped density optimisation for four agricultural wastes (particles of coconut, periwinkle, palm kernel and egg shells, performance analysis for comparative basis is made. This paper pioneers a study direction in which optimisation of process variables are pursued using Taguchi method integrated with the Pareto 80-20 rule. Negative percentage improvements resulted when the optimal tapped density was compared with the average tapped density. However, the performance analysis between optimal tapped density and the peak tapped density values yielded positive percentage improvements for the four filler particles. The performance analysis results validate the effectiveness of using the Taguchi method in improving the tapped density properties of the filler particles. The application of the Pareto 80-20 rule to the table of parameters and levels produced revised tables of parameters and levels which helped to identify the factor-levels position of each parameter that is economical to optimality. The Pareto 80-20 rule also produced revised S/N response tables which were used to know the relevant S/N ratios that are relevant to optimality.

  17. Demonstration of GTS Duratek Process for Stabilizing Mercury Contaminated (<260 ppm) Mixed Wastes. Mixed Waste Focus Area. OST Reference No. 2409

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1999-09-01

    Mercury-contaminated wastes in many forms are present at various U. S. Department of Energy (DOE) sites. At least 26 different DOE sites have this type of mixed low-level waste in their storage facilities, totaling approximately 6,000 m3. Mercury contamination in the wastes at DOE sites presents a challenge because it exists in various forms, such as soil, sludges, and debris, as well as in different chemical species of mercury. Stabilization is of interest for radioactively contaminated mercury waste (<260 ppm Hg) because of its success with particular wastes, such as soils, and its promise of applicability to a broad range of wastes. However, stabilization methods must be proven to be adequate to meet treatment standards. They must also be proven feasible in terms of economics, operability, and safety. This report summarizes the findings from a stabilization technology demonstration conducted by GTS Duratek, Inc. Phase I of the study involved receipt and repackaging of the material, followed by preparations for waste tracking. Phase II examined the bench-scale performance of grouting at two different loadings of waste to grouted mass. Phase III demonstrated in-drum mixing and solidification using repackaged drums of sludge. Phase IV initially intended to ship final residues to Envirocare for disposal. The key results of the demonstration are as follows: (1) Solidification tests were performed at low and high waste loading, resulting in stabilization of mercury to meet the Universal Treatment Standard of 0.025 mg/L at the low loading and for two of the three runs at the high loading. The third high-loading run had a Toxicity Characteristic Leaching Procedure (TCLP) of 0.0314 mg/L. (2) Full-drum stabilization using the low loading formula was demonstrated. (3) Organic compound levels were discovered to be higher than originally reported, including the presence of some pesticides. Levels of some radionuclides were much higher than initially reported. (4

  18. Properties of radioactive wastes and waste containers. Progress report No. 7, October--December 1977

    Energy Technology Data Exchange (ETDEWEB)

    Colombo, P.; Neilson, Jr, R. M.

    1978-04-01

    Trial solidifications were made using portland type II cement--sodium silicate as the solidification agent. The sodium silicate was found to produce an initial rapid set for all wastes because of the precipitation of relatively insoluble silicate compounds upon reaction with soluble multivalent cations in solution in the cement-waste mixture. Achievement of the ultimate waste form strength required time intervals similar to waste forms produced using portland cement alone. A hard waste form was not obtained within seventy-eight days with formulations used to solidify boric acid waste. The flash points and flame points of Pioneer 221 bitumen and bitumen waste forms were determined using the Cleveland open cup method. The bitumen alone had a flash point of 610 +- 2/sup 0/F and a flame point of 668 +- 4/sup 0/F. The bitumen waste forms exhibited similar flame points but slightly higher (15 to 20/sup 0/F) flash points were measured. Self-irradiation exposure dose curves were calculated for BWR and PWR waste forms. These curves indicate the cumulative waste form exposure dose with time and serve as the basis for radiation stability experiments. Waste form specific activities of 0.01 to 100 Ci/ft/sup 3/ were considered. Bitumen waste forms containing sodium sulfate from the solidification of BWR chemical regenerative waste were prepared and leach tested. These specimens swelled and cracked during leach testing, exposing substantial new surface area to the leachant. The volumetric efficiencies of urea-formaldehyde and portland type II cement for various wastes and waste/binder ratios were calculated from compression test specimen data.

  19. Statement of Work (SOW) for FY 2001 to FY 2006 for the Hanford Low Activity Tank Waste Performance Assessment Program

    Energy Technology Data Exchange (ETDEWEB)

    PUIGH, R.J.

    2000-07-25

    This document describes the tasks included in the Hanford Low-Activity Tank Waste Performance Assessment activity though the close of the project in 2028. Near-term (2001-2006) tasks are described in detail, while tasks further in the future are simply grouped by year. The major tasks are displayed in the table provided. The major goals of the performance assessment activity are to provide the technical basis for the Department of Energy to continue to authorize the construction of disposal facilities, the onsite disposal of immobilized low-activity Hanford tank waste in those facilities, and the closure of the disposal facilities. Other significant goals are to provide the technical basis for the setting of the specifications of the immobilized waste and to support permitting of the disposal facilities.

  20. Environmental performance of household waste management in Europe - an example of 7 countries

    DEFF Research Database (Denmark)

    Andreasi Bassi, Susanna; Christensen, Thomas Højlund; Damgaard, Anders

    2017-01-01

    An attributional life cycle assessment (LCA) of the management of 1 ton of household waste was conducted in accordance with ISO 14044:2006 and the ILCD Handbook for seven European countries, namely Germany, Denmark, France, UK, Italy, Poland and Greece, representing different household waste...... mainly on the composition of the energy being substituted. Sensitivity analysis and a data quality assessment identified a range of critical parameters, suggesting from where better data should be obtained. The study concluded that household waste management is environmentally the best in European...... compositions, waste management practices, technologies, and energy systems. National data were collected from a range of sources regarding household waste composition, household sorting efficiency, collection, waste treatments, recycling, electricity and heat composition, and technological efficiencies...

  1. Experimental study of segregation in plane front solidification and its relevance to iron meteorite solidification

    Science.gov (United States)

    Sellamuthu, R.; Goldstein, J. I.

    1983-01-01

    A directional solidification technique was developed and applied to the problem of fractional crystallization of an iron meteorite parent body. Samples of Fe-Ni alloys close to meteorite compositions and containing S, P, and C were made. The solidified structures contain secondary phases such as sulphides within the proeutectic single crystal austenite (taenite). As a result of these experiments, we propose that the secondary phases observed in iron meteorites were formed during primary solidification of austenite (taenite). The measured composition profiles of Ni, P and C in the alloys were used to explain the elemental distribution within a chemical group of iron meteorites. An analytical procedure was applied to determine the equilibrium distribution coefficients as a function of fraction solidified for Ni and P from the composition profiles. The distribution coefficients of Ni and P agree with previous values. These distribution coefficients are of particular interest in the determination of the elemental distributions in iron meteorites.

  2. Release of radionuclides and chelating agents from cement-solidified decontamination low-level radioactive waste collected from the Peach Bottom Atomic Power Station Unit 3

    Energy Technology Data Exchange (ETDEWEB)

    Akers, D.W.; Kraft, N.C.; Mandler, J.W. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

    1994-03-01

    As part of a study being performed for the Nuclear Regulatory Commission (NRC), small-scale waste-form specimens were collected during a low oxidation-state transition-metal ion (LOMI)-nitric permanganate (NP)-LOMI solidification performed in October 1989 at the Peach Bottom Atomic Power Station Unit 3. The purpose of this program was to evaluate the performance of cement-solidified decontamination waste to meet the low-level waste stability requirements defined in the NRC`s ``Technical Position on Waste Form,`` Revision 1. The samples were acquired and tested because little data have been obtained on the physical stability of actual cement-solidified decontamination ion-exchange resin waste forms and on the leachability of radionuclides and chelating agents from those waste forms. The Peach Bottom waste-form specimens were subjected to compressive strength, immersion, and leach testing in accordance with the NRC`s ``Technical Position on Waste Form,`` Revision 1. Results of this study indicate that the specimens withstood the compression tests (>500 psi) before and after immersion testing and leaching, and that the leachability indexes for all radionuclides, including {sup 14}C, {sup 99}{Tc}, and {sup 129}I, are well above the leachability index requirement of 6.0, required by the NRC`s ``Technical Position on Waste Form,`` Revision 1.

  3. Analysing the sustainability performance and critical improvement factors of urban municipal waste systems - Case study Trondheim

    OpenAIRE

    Unander, Silje Madalena Oliveira

    2017-01-01

    The management of the natural output of consumption, waste, has to become more sustainable. Ideally this would mean that it simply ceased to exist, but as unrealistic that may be, the current discourse in waste legislation and management is on increasing the material recycling rate. This is a part of the circular economy. Analysing waste management systems is crucial to know what effect different measures might have on the actual recycling rate. In turn, these measures might impact the energ...

  4. Waste Metal For Improving Concrete Performance And Utilisation As An Alternative Of Reinforcement Bar

    OpenAIRE

    Tanvir Qureshi; Mustaq Ahmed

    2015-01-01

    Waste material disposal is considered as a difficult issue to adopt in current world. Waste metal, which has been recognised as a major problem in the environment and resource deficiency, could have important implications in the concrete construction industries. Waste metal utilisation in construction of reinforced cement concrete (RCC) works is immerging in recent time. Construction industries are looking for cost effective structural materials and utilisation of renewable materi...

  5. Laboratory Testing of Bulk Vitrified Low-Activity Waste Forms to Support the 2005 Integrated Disposal Facility Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Eric M.; McGrail, B. Peter; Bagaasen, Larry M.; Rodriguez, Elsa A.; Wellman, Dawn M.; Geiszler, Keith N.; Baum, Steven R.; Reed, Lunde R.; Crum, Jarrod V.; Schaef, Herbert T.

    2006-06-30

    The purpose of this report is to document the results from laboratory testing of the bulk vitri-fied (BV) waste form that was conducted in support of the 2005 integrated disposal facility (IDF) performance assessment (PA). Laboratory testing provides a majority of the key input data re-quired to assess the long-term performance of the BV waste package with the STORM code. Test data from three principal methods, as described by McGrail et al. (2000a; 2003a), are dis-cussed in this testing report including the single-pass flow-through test (SPFT) and product con-sistency test (PCT). Each of these test methods focuses on different aspects of the glass corrosion process. See McGrail et al. (2000a; 2003a) for additional details regarding these test methods and their use in evaluating long-term glass performance. In addition to evaluating the long-term glass performance, this report discusses the results and methods used to provided a recommended best estimate of the soluble fraction of 99Tc that can be leached from the engineer-ing-scale BV waste package. These laboratory tests are part of a continuum of testing that is aimed at improving the performance of the BV waste package.

  6. Laboratory Testing of Bulk Vitrified Low-Activity Waste Forms to Support the 2005 Integrated Disposal Facility Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Eric M.; McGrail, B. Peter; Bagaasen, Larry M.; Rodriguez, Elsa A.; Wellman, Dawn M.; Geiszler, Keith N.; Baum, Steven R.; Reed, Lunde R.; Crum, Jarrod V.; Schaef, Herbert T.

    2005-03-31

    The purpose of this report is to document the results from laboratory testing of the bulk vitri-fied (BV) waste form that was conducted in support of the 2005 integrated disposal facility (IDF) performance assessment (PA). Laboratory testing provides a majority of the key input data re-quired to assess the long-term performance of the BV waste package with the STORM code. Test data from three principal methods, as described by McGrail et al. (2000a; 2003a), are dis-cussed in this testing report including the single-pass flow-through test (SPFT) and product con-sistency test (PCT). Each of these test methods focuses on different aspects of the glass corrosion process. See McGrail et al. (2000a; 2003a) for additional details regarding these test methods and their use in evaluating long-term glass performance. In addition to evaluating the long-term glass performance, this report discusses the results and methods used to provided a recommended best estimate of the soluble fraction of 99Tc that can be leached from the engineer-ing-scale BV waste package. These laboratory tests are part of a continuum of testing that is aimed at improving the performance of the BV waste package.

  7. Multi-criteria group decision making for evaluating the performance of e-waste recycling programs under uncertainty.

    Science.gov (United States)

    Wibowo, Santoso; Deng, Hepu

    2015-06-01

    This paper presents a multi-criteria group decision making approach for effectively evaluating the performance of e-waste recycling programs under uncertainty in an organization. Intuitionistic fuzzy numbers are used for adequately representing the subjective and imprecise assessments of the decision makers in evaluating the relative importance of evaluation criteria and the performance of individual e-waste recycling programs with respect to individual criteria in a given situation. An interactive fuzzy multi-criteria decision making algorithm is developed for facilitating consensus building in a group decision making environment to ensure that all the interest of individual decision makers have been appropriately considered in evaluating alternative e-waste recycling programs with respect to their corporate sustainability performance. The developed algorithm is then incorporated into a multi-criteria decision support system for making the overall performance evaluation process effectively and simple to use. Such a multi-criteria decision making system adequately provides organizations with a proactive mechanism for incorporating the concept of corporate sustainability into their regular planning decisions and business practices. An example is presented for demonstrating the applicability of the proposed approach in evaluating the performance of e-waste recycling programs in organizations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Developments in life cycle assessment applied to evaluate the environmental performance of construction and demolition wastes.

    Science.gov (United States)

    Bovea, M D; Powell, J C

    2016-04-01

    This paper provides a review of the literature that applies the life cycle assessment (LCA) methodology to the assessment of the environmental performance of the life cycle of construction and demolition waste (CDW) management systems. This article is focused on generating a general mapping of the literature and on identifying the best practices in compliance with LCA framework and proposing directions for future LCA studies in this field. The temporal evolution of the research in this field and the aim of the studies have grown in parallel with the legal framework related to waste and energy efficiency of buildings. Most studies have been published in Europe, followed by USA. Asia and Australia, being at an incipient application stage to the rest of the world. Topics related to "LCA of buildings, including their EoL" and "LCA of general CDW management strategies" are the most frequently analysed, followed by "LCA of EoL of construction elements" and "LCA of natural material vs recycled material". Regarding the strategies, recycling off-site and incineration, both combined with landfill for the rejected fractions, are the most commonly applied. Re-use or recycling on-site is the strategy least applied. The key aspect when LCA is applied to evaluate CDW management systems is the need to normalise which processes to include in the system boundary and the functional unit, the use of inventory data adapted to the context of the case study and the definition of a common set of appropriate impact assessment categories. Also, it is important to obtain results disaggregated by unit processes. This will allow the comparison between case studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. EFFECT OF FEEDING COOKED HATCHERY WASTE ON THE PERFORMANCE OF BROILERS

    Directory of Open Access Journals (Sweden)

    Sohail Hassan Khan and Bashir Mahmood Bhatti

    2002-01-01

    Full Text Available Raw hatchery waste was cooked with water at 2:1 ratio for 15 minutes and then oven dried at 65C and ground. Hatchery waste meal (HWM thus prepared contained 32% crude protein, 16% ether extract, 0.9% crude fibre, 40% total ash, 11.1% nitrogen free extract, 20% calcium and 0.6 % available phosphorous with no E.Coli and Salmonella. In biological evaluation trail, non significant differences was observed among rations in which HWM replaced the fish meal at 0(A, 25(B, 50(C and 75 (D levels in broiler rations. These rations showed that protein efficiency ratios were 1.68, 1.79, 1.65,and 1.64 apparent biological value 59.96, 60.25, 59.75 and 58.32% respectively, indicating better balance of amino acid in HWM to be replaced with fish meal,. In 6 weeks performance trail, the body weight gains were 1807.69, 1916.39, 1788.39 and 1635.66 gm in A, B, C and D rations, respectively. Whereas, FCR values were 2.59, 2.32, 2.43 and 2.63 in the corresponding groups, which shows no significant difference among all rations. The cost per chick to market age was lowest in ration containing high level of HWM (7.5% and highest in ration containing high level of fish meal (10% indicating maximum replacement of fish meal by HWM in broiler ration is economical. Similarly, slaughtering data revealed no significant difference among all rations in all parameters. It may be concluded that the HWM can completely replace fish meal in commercial broiler rations.

  10. Performance assessments for radioactive waste repositories; the rate of movement of faults

    Science.gov (United States)

    Trask, Newell J.

    1982-01-01

    Performance assessments of mined repositories for radioactive waste require estimates of the likelihood of fault movements and earthquakes that may affect the repository and its surrounding ground water flow system. Some previous assessments have attempted to estimate the rate of formation of new faults; some have relied heavily on historic seismicity or the time of latest movement on faults. More appropriate emphasis is on the identification of faults that have been active or may have been active under the present teconic regime in a broad region and on estimates of the long-term rate of movement of such faults. Faults that have moved under the current stress field, even at low rates, are likely to move again during the time the wastes will remain toxic. A continuum exists for the present rate of movement of faults which ranges from 10 mm per year for obviously active faults along the western margin of the North American plate to as low as 10 -4 mm per year for recently documented faults in the Atlantic Coast province. On the basis of regional consistency in movement rates and constraints imposed by geomorphology, I derive upper bounds for the rates of occurrence of fault offsets for various crustal stress provinces in the conterminous United States. These upper bounds are not meant to substitute for detailed studies of specific faults and seismicity at specific sites. They can help to reduce the considerable uncertainty that attaches to all estimates of future tectonic activity. The principal uncertainty in their estimation is the manner in which total slip across faults is distributed among discrete events especially in regions in which the rate of movement is very low.

  11. Performance catalytic ozonation over the carbosieve in the removal of toluene from waste air stream.

    Science.gov (United States)

    Samarghandi, Mohammad Reza; Babaee, Seyed Alireza; Ahmadian, Mohammad; Asgari, Ghorban; Ghorbani Shahna, Farshid; Poormohammadi, Ali

    2014-01-01

    Toluene is a volatile organic compound, one of 189 hazardous air pollutants (HAPs) and the most important pollutant found in most industries and indoor environments; owing to its adverse health, toluene must be treated before being released into the environment. In this research study, a continuous-flow system (including an air compressor, silica gel filters and activated charcoal, impinger, an ozone generation and a fixed bed reactor packed with the carbosieve in size 1.8-2.3 mm, specific surface: 972 m2/g,) was used. This glass reactor was 0.7 m in height; at a distance of 0.2 m from its bottom, a mesh plane was installed so as to hold the adsorbent. Moreover, 3 l/min oxygen passed through this system, 0.43 g/h ozone was prepared. The flow rate of waste airstream was 300 ml/min. The efficiency of this system for removal of toluene was compared under the same experimental conditions. Under similar conditions, performance of catalytic ozonation was better in toluene removal than that of ozonation and carbosieve alone. On average, increasing the removal efficiency was 45% at all concentrations. When carbosieve and ozone come together, their synergistic effects increased on toluene degradation. Catalytic ozonation is a suitable, high-efficient and available method for removing toluene from various concentrations of waste air stream. This process due to the short contact time, low energy consuming and making use of cheap catalysts can be used as a novel process for removing various concentrations of volatile organic compounds.

  12. Performance of a large-scale melter off-gas system utilizing simulated SRP DWPF waste

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, J L; Randall, C T

    1984-03-01

    The Department of Energy and the DuPont Company have begun construction of a Defense Waste Processing Facility to immobilize radioactive waste now stored as liquids at the Department of Energy's Savannah River Plant. The immobilization process solidifies waste sludge by vitrification into a leach-resistant borosilicate glass. Development of the process has been the responsibility of the Savannah River Laboratory. As part of the development, two large-scale glass melter systems have been designed and operated with simulated waste. Experimental data from these operations show that process requirements will be met. 6 references, 8 figures, 4 tables.

  13. Report: transboundary hazardous waste management. part II: performance auditing of treatment facilities in importing countries.

    Science.gov (United States)

    Chang, Tien-Chin; Ni, Shih-Piao; Fan, Kuo-Shuh; Lee, Ching-Hwa

    2006-06-01

    Before implementing the self-monitoring model programme of the Basel Convention in the Asia, Taiwan has conducted a comprehensive 4-year follow-up project to visit the governmental authorities and waste-disposal facilities in the countries that import waste from Taiwan. A total of nine treatment facilities, six of which are reported in this paper, and the five countries where the plants are located were visited in 2001-2002. France, Belgium and Finland primarily handled polychlorinated biphenyl capacitors, steel mill dust and metal waste. The United States accepted metal sludge, mainly electroplating sludge, from Taiwan. Waste printed circuit boards, waste wires and cables, and a mixture of waste metals and electronics were the major items exported to China. Relatively speaking, most treatment plants for hazardous waste paid close attention to environmental management, such as pollution control and monitoring, site zoning, system management regarding occupational safety and hygiene, data management, permits application, and image promotion. Under the tight restrictions formulated by the central environment agency, waste treatment plants in China managed the environmental issues seriously. For example, one of the treatment plants had ISO 14001 certification. It is believed that with continuous implementation of regulations, more improvement is foreseeable. Meanwhile, Taiwan and China should also continuously enhance their collaboration regarding the transboundary management of hazardous waste.

  14. Performance analysis of a low-temperature waste heat-driven adsorption desalination prototype

    KAUST Repository

    Thu, Kyaw

    2013-10-01

    This paper discusses the performance analysis of an advanced adsorption desalination (AD) cycle with an internal heat recovery between the condenser and the evaporator. The AD cycle employs the adsorption-desorption principles to convert sea or brackish water into high-grade potable water with total dissolved solids (TDS) less than 10 ppm (mg/L) utilizing low-temperature heat source. The salient features of the AD cycle are the utilization of low temperature waste heat (typically 55 C to 85 C) with the employment of an environment-friendly silica gel/water pair and the low maintenance as it has no major moving parts other than the pumps and valves. For improved performance of the AD pilot plant, the internal heat recovery scheme between the condenser and evaporator has been implemented with a run-about water circuit between them. The efficacy of the scheme is analyzed in terms of key performance indicators such as the specific daily water production (SDWP) and the performance ratio (PR). Extensive experiments were performed for assorted heat source temperatures ranging from 70 C to 50 C. From the experiments, the SDWP of the AD cycle with the proposed heat recovery scheme is found to be 15 m3 of water per ton of silica gel that is almost twice that of the yield obtained by a conventional AD cycle for the same operation conditions. Another important finding of AD desalination plant is that the advanced AD cycle could still be operational with an inlet heat source temperature of 50 C and yet achieving a SDWP of 4.3 m3 - a feat that never seen by any heat-driven cycles. © 2013 Elsevier Ltd. All rights reserved.

  15. Hanford facility dangerous waste permit application, 325 hazardous waste treatment units. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    This report contains the Hanford Facility Dangerous Waste Permit Application for the 325 Hazardous Waste Treatment Units (325 HWTUs) which consist of the Shielded Analytical Laboratory, the 325 Building, and the 325 Collection/Loadout Station Tank. The 325 HWTUs receive, store, and treat dangerous waste generated by Hanford Facility programs. Routine dangerous and/or mixed waste treatment that will be conducted in the 325 HWTUs will include pH adjustment, ion exchange, carbon absorption, oxidation, reduction, waste concentration by evaporation, precipitation, filtration, solvent extraction, solids washing, phase separation, catalytic destruction, and solidification/stabilization.

  16. GPU-accelerated phase-field simulation of dendritic solidification in a binary alloy

    Science.gov (United States)

    Yamanaka, Akinori; Aoki, Takayuki; Ogawa, Satoi; Takaki, Tomohiro

    2011-03-01

    The phase-field simulation for dendritic solidification of a binary alloy has been accelerated by using a graphic processing unit (GPU). To perform the phase-field simulation of the alloy solidification on GPU, a program code was developed with computer unified device architecture (CUDA). In this paper, the implementation technique of the phase-field model on GPU is presented. Also, we evaluated the acceleration performance of the three-dimensional solidification simulation by using a single NVIDIA TESLA C1060 GPU and the developed program code. The results showed that the GPU calculation for 5763 computational grids achieved the performance of 170 GFLOPS by utilizing the shared memory as a software-managed cache. Furthermore, it can be demonstrated that the computation with the GPU is 100 times faster than that with a single CPU core. From the obtained results, we confirmed the feasibility of realizing a real-time full three-dimensional phase-field simulation of microstructure evolution on a personal desktop computer.

  17. Anaerobic digestion of municipal solid waste composed of food waste, wastepaper, and plastic in a single-stage system: performance and microbial community structure characterization.

    Science.gov (United States)

    Wan, Shungang; Sun, Lei; Douieb, Yaniv; Sun, Jian; Luo, Wensui

    2013-10-01

    The performance of municipal organic solid waste anaerobic digestion was investigated using a single-stage bioreactor, and the microbial community structures were characterized during the digestion. The results showed that the biogas and methane production rates were 592.4 and 370.1L/kg with volatile solid added at the ratio of 2:1:1 for food waste, wastepaper, and plastic based on dry weight. The methane volume concentration fluctuated between 44.3% and 75.4% at steady stage. Acetic acid, propionic acid, and butyric acid were the major volatile fatty acids produced during the digestion process. The anaerobic process was not inhibited by the accumulation of ammonia and free ammonia. The bacterial community was found to consist of at least 21 bands of bacteria and 12 bands of archaea at the steady state. All of the results indicated that the mixture of food waste, wastepaper, and plastic could be efficiently co-digested using the anaerobic digestion system. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Simulation of continuous cast steel product solidification

    Directory of Open Access Journals (Sweden)

    Ardelean, E.

    2007-06-01

    Full Text Available Primary cooling – inside the tundish – has a great impact over the thickness of the solidified steel crust. If on exiting the tundish the crust is too thin, it can punch and break, as a result of the ferrostatic pressure exerted from the inside by the liquid steel as well as because of the weight of the molten steel. The parameters that influence the amount of dissipated heat depend on the cooling water flow of the tundish, on the pressure and temperature of the cooling water but also on the overheating of the continuously cast steel. The secondary cooling takes place at the exit of the semi-finished product from the tundish, when the solidification is supposed to take place all along the cross section of the strand. In order to achieve it, in addition to a correctly managed primary cooling, it is necessary to obtain the proper correlation of the factors that influence the secondary cooling as well: the water flow rate long the three zones of the installation and its pressure in the secondary circuit. All these have in view a proper solidification length; an intense cooling can generate cracks due to the thermal stress, while a too slow cooling can generate a partial solidification of the strand up to the cropping machine area. The paper presents a mathematical simulation of the continuously cast steel solidification.

    El enfriamiento primario del cristalizador tiene una gran importancia sobre el espesor de la costra de acero solidificado. Si al salir del cristalizador, esta costra es demasiado sutil, bajo la acción de la presión ferro estática ejercitada por el acero líquido del interior y gracias el peso propio del hilo, ésta, puede perforar resultando su rompimiento. Los parámetros que influenyen sobre la cantidad de calor cedida dependen del agua de enfriamiento del catalizador, de la presión y de la temperatura de agua de enfriamiento, pero también del sobrecalentamiento del acero fundido continuamente. A la salida del

  19. Feedback control of unstable cellular solidification fronts

    Science.gov (United States)

    Pons, A. J.; Karma, A.; Akamatsu, S.; Newey, M.; Pomerance, A.; Singer, H.; Losert, W.

    2007-02-01

    We present a feedback control scheme to stabilize unstable cellular patterns during the directional solidification of a binary alloy. The scheme is based on local heating of cell tips which protrude ahead of the mean position of all tips in the array. The feasibility of this scheme is demonstrated using phase-field simulations and, experimentally, using a real-time image processing algorithm, to track cell tips, coupled with a movable laser spot array device to heat the tips locally. We demonstrate, both numerically and experimentally, that spacings well below the threshold for a period-doubling instability can be stabilized. As predicted by the numerical calculations, cellular arrays become stable with uniform spacing through the feedback control which is maintained with minimal heating.

  20. Numerical simulation on directional solidification of Al-Ni-Co alloy based on FEM

    OpenAIRE

    Yang Zhili; Chen Dengming; Tian Shilong

    2010-01-01

    The ratio, of the temperature gradient at the solidification front to the solidification rate of solid-liquid interface, plays a large part in columnar grain growth. The transient temperature fields of directional solidification of Al-Ni-Co alloy were studied by employing a finite element method. The temperature gradient at the solidification front and the solidification rate were analyzed for molten steels pouring at different temperatures. The results show that with different initial pourin...

  1. Role of natural analogs in performance assessment of nuclear waste repositories

    Energy Technology Data Exchange (ETDEWEB)

    Sagar, B.; Wittmeyer, G.W. [Center for Nuclear Waste Regulatory Analysis, San Antonio, TX (United States)

    1995-09-01

    Mathematical models of the flow of water and transport of radionuclides in porous media will be used to assess the ability of deep geologic repositories to safely contain nuclear waste. These models must, in some sense, be validated to ensure that they adequately describe the physical processes occurring within the repository and its geologic setting. Inasmuch as the spatial and temporal scales over which these models must be applied in performance assessment are very large, validation of these models against laboratory and small-scale field experiments may be considered inadequate. Natural analogs may provide validation data that are representative of physico-chemical processes that occur over spatial and temporal scales as large or larger than those relevant to repository design. The authors discuss the manner in which natural analog data may be used to increase confidence in performance assessment models and conclude that, while these data may be suitable for testing the basic laws governing flow and transport, there is insufficient control of boundary and initial conditions and forcing functions to permit quantitative validation of complex, spatially distributed flow and transport models. The authors also express their opinion that, for collecting adequate data from natural analogs, resources will have to be devoted to them that are much larger than are devoted to them at present.

  2. Effect of alternate cooling systems and beneficial use of waste heat on power plant performance

    Energy Technology Data Exchange (ETDEWEB)

    Rao, D.K.; Porter, R.W.

    1978-11-01

    The performance and cost of alternate closed-cycle cooling systems for steam--electric power plants are discussed. Included are cooling ponds, spray canals and mechanical- and natural-draft wet cooling towers. Besides equipment, operational and maintenance costs, loss of generating capacity is determined on a seasonal basis in order to determine life-cycle costs relative to once-through cooling. In addition, two beneficial uses of waste heat are similarly analyzed: once-through discharge of condenser coolant into a municipal water supply and interaction of a conventional cooling system with a wastewater treatment plant. Both typical nuclear- and fossil-fueled power plants are considered throughout. Meteorological and system parameters were taken for the Chicago area as an example. Plant heat rates, availability and unit costs were selected from the literature. A new unified analysis of closed-cycle-cooling system performance is developed in order to facilitate computation of loss of generating capacity. The order of cooling systems in terms of increasing cost is: once-through, pond, natural-draft wet tower, spray canal and mechanical-draft wet tower. Alternatively, once-through discharge into a municipal water supply would save 1 to 2% of power-plant fuel and 14 to 22% of residential water-heater energy. Or, the interactive wastewater plant would save 2 to 15% of treatment costs, favoring larger facilities.

  3. Treatment of high strength aqueous wastes in a thermophilic aerobic membrane reactor (TAMR): performance and resilience.

    Science.gov (United States)

    Collivignarelli, Maria Cristina; Abbà, Alessandro; Bertanza, Giorgio; Barbieri, Giacomo

    2017-12-01

    In the present work, the thermophilic aerobic membrane reactor technology was studied for the treatment of high strength aqueous wastes mainly containing dyes, surfactants and solvents. The thermophilic biomass resilience and the process stability under critical conditions (such as rapid rise of the mixed liquor pH, oxygen supply interruption, etc.) were also evaluated. The experimental work was carried out with the use of a pilot plant at semi-industrial scale, which was managed throughout for 14 months; the operation temperature was 49 °C and the organic loading rate was increased from 3 to 12 kgCOD m-3 d-1. Critical conditions, especially the interruption of oxygen supply, affected the pilot plant performance but did not cause a complete system break down. After the temporary reduction of process performance, also proven by the decrease in the oxygen consumption, the normal working conditions were restored. Moreover, the longer non-aerated phase involved a significant reduction (40%) of volatile suspended solids concentration in the biological reactor and the increase of 30% in foaming power; nevertheless, once the oxygen supply was reactivated, optimal conditions were rapidly restored. Therefore, the study showed the high resilience of the thermophilic biomass, which was able to recover full functionality after critical events.

  4. Addendum to the performance assessment analysis for low-level waste disposal in the 200 west area active burial grounds

    Energy Technology Data Exchange (ETDEWEB)

    Wood, M.I., Westinghouse Hanford

    1996-12-20

    An addendum was completed to the performance assessment (PA) analysis for the active 200 West Area low-level solid waste burial grounds. The addendum includes supplemental information developed during the review of the PA analysis, an ALARA analysis, a comparison of PA results with the Hanford Groundwater Protection Strategy, and a justification for the assumption of 500 year deterrence to the inadvertent intruder.

  5. Analytical and experimental evaluation of solid waste drum fire performance volumes I and II

    Energy Technology Data Exchange (ETDEWEB)

    Hecker, C.F., [Los Alamos Technical Associates, Inc., Kennewick, WA (United States); Rhodes, B.T.; Beitel, J.J.; Gottuk, D.T.; Beyler, C.L.; Rosenbaum, E.R., [Hughes Associates, Inc., Columbia, MD (United States)

    1995-04-28

    Fire hazards associated with drum storage of radioactively contaminated wastes are a major concern in DOE facilities design for long term storage of solid wastes in drums. These facilities include drums stored in pallet arrays and in rack storage systems. This report details testing in this area

  6. Environmental performance of construction waste: Comparing three scenarios from a case study in Catalonia, Spain.

    Science.gov (United States)

    Ortiz, O; Pasqualino, J C; Castells, F

    2010-04-01

    The main objective of this paper is to evaluate environmental impacts of construction wastes in terms of the LIFE 98 ENV/E/351 project. Construction wastes are classified in accordance with the Life Program Environment Directive of the European Commission. Three different scenarios to current waste management from a case study in Catalonia (Spain) have been compared: landfilling, recycling and incineration, and these scenarios were evaluated by means of Life Cycle Assessment. The recommendations of the Catalan Waste Catalogue and the European Waste Catalogue have been taken into account. Also, the influence of transport has been evaluated. Results show that in terms of the Global Warming Potential, the most environmentally friendly treatment was recycling, followed by incineration and lastly landfilling. According to the influence of treatment plants location on the GWP indicator, we observe that incineration and recycling of construction wastes are better than landfilling, even for long distances from the building site to the plants. This is true for most wastes except for the stony types, than should be recycled close to the building site. In summary, data from construction waste of a Catalan case study was evaluated using the well established method of LCA to determine the environmental impacts. Copyright 2009 Elsevier Ltd. All rights reserved.

  7. Performance assessment of the direct disposal in unsaturated tuff or spent nuclear fuel and high-level waste owned by USDOE: Volume 2, Methodology and results

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P. [ed.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservations. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM.

  8. Evaluating the performance and intellectual structure of construction and demolition waste research during 2000-2016.

    Science.gov (United States)

    Liu, Yanli; Sun, Tiantian; Yang, Lie

    2017-08-01

    Construction and demolition (C&D) waste diminishes scarce land resources and endangers human health and the surrounding environment. Quantitative and visualized analysis was conducted to evaluate worldwide scientific research output on C&D waste from 2000 to 2016. The related information of 857 publications was collected from SCI-Expanded database and statistically analyzed. The number of documents about C&D waste presented a general growth during the last 17 years. Construction and Building Materials publication ranked first in the most productive journals. China and Spain acted as dominated roles comparing to other countries, and Hong Kong Polytechnic University was the institution with the largest amount of C&D waste research. Recycled aggregates, sustainable C&D waste management, and the rewarding program and commerce system were the hottest topics during 2000-2016 and in the near future according to the intellectual structure analysis.

  9. In situ observations of graphite formation during solidification of cast iron

    DEFF Research Database (Denmark)

    Bjerre, Mathias Karsten

    . This is important since the shapes of the graphite precipitates play a determining role for the properties of grey cast irons. However, to reach the full potential of cast irons and enable high-performance light-weight designs, more in-depth knowledge of the mechanisms controlling graphite growth and morphological...... cast iron it is important to estimate the density of nodules as well as the distribution of nodule shapes and sizes at room temperature. This emphasises the importance of models which can correctly describe the nucleation and growth of spheroidal graphite during solidification. In this thesis...... state growth presented in the present thesis. From the analysis it is clear that the presented data is of an unprecedented quality and that it represents a solid basis for validation of future models. Solidification simulations of a ductile cast iron component highlights the importance of the nucleation...

  10. Basic Research on a Latent Heat Thermal Energy Storage by Direct Contact Melting and Solidification

    Science.gov (United States)

    Saito, Akihiro; Saito, Akio; Utaka, Yoshio; Okuda, Kenichi; Katayama, Kozo

    A basic experimental research on a latent heat thermal energy storage system, utilizing a simple and effective heat exchange mechanism by a direct contact between the phase change material (PCM) and the heat transfer fluid (HTF) , was shown. In this report, authors proposed the direct contact latent heat thermal energy storage system using industrial paraffin and n-Eicosane as the PCM, and using water as the HTF. The observations were performed concerning the HTF separation from the solid PCM in the solidification process (heat discharging process), and concerning the water pass formation within the solid PCM. Then, it was confirmed that the system worked effectively by using n-Eicosane as the PCM. And authors discussed the mechanism of direct contact solidification process from experimental results.

  11. A mathematical model for distribution of calcium in silicon by vacuum directional solidification

    Directory of Open Access Journals (Sweden)

    Zheng D.

    2016-01-01

    Full Text Available Calcium is one of the main impurity elements in silicon. The removal of calcium strongly affects the quality of the polycrystalline silicon ingot produced by a vacuum directional solidification method. Based on the considerations of the theory of segregation, mass transfer and evaporation during vacuum directional solidification process, a mathematical model for calcium distribution in silicon was proposed and it can be used to explain the removal mechanism. In order to confirm the mathematical model, an industrial scale experiment on UMG-Si with an initial purity of 99.98 wt. % was performed. Since the reaction temperature strongly influences both the evaporation and segregation of calcium, the dependences of effective segregation coefficient (keff and the evaporation coefficient (kE on temperature were carefully investigated. The results showed that the proposed mathematical model was highly consistent with the experimental data and the calcium removal efficiency mainly relied on the evaporation step.

  12. The evolution of structural and chemical heterogeneity during rapid solidification at gas atomization

    Science.gov (United States)

    Golod, V. M.; Sufiiarov, V. Sh

    2017-04-01

    Gas atomization is a high-performance process for manufacturing superfine metal powders. Formation of the powder particles takes place primarily through the fragmentation of alloy melt flow with high-pressure inert gas, which leads to the formation of non-uniform sized micron-scale particles and subsequent their rapid solidification due to heat exchange with gas environment. The article presents results of computer modeling of crystallization process, simulation and experimental studies of the cellular-dendrite structure formation and microsegregation in different size particles. It presents results of adaptation of the approach for local nonequilibrium solidification to conditions of crystallization at gas atomization, detected border values of the particle size at which it is possible a manifestation of diffusionless crystallization.

  13. Evaluation of municipal solid waste management performance by material flow analysis: Theoretical approach and case study.

    Science.gov (United States)

    Zaccariello, Lucio; Cremiato, Raffaele; Mastellone, Maria Laura

    2015-10-01

    The main role of a waste management plan is to define which is the combination of waste management strategies and method needed to collect and manage the waste in such a way to ensure a given set of targets is reached. Objectives have to be sustainable and realistic, consistent with the environmental policies and regulations and monitored to verify the progressive achievement of the given targets. To get the aim, the setting up and quantification of indicators can allow the measurement of efficiency of a waste management system. The quantification of efficiency indicators requires the developing of a material flow analysis over the system boundary, from waste collection to secondary materials selling, processing and disposal. The material flow analysis has been carried out with reference to a case study for which a reliable, time- and site-specific database was available. The material flow analysis allowed the evaluation of the amount of materials sent to recycling, to landfilling and to waste-to-energy, by highlighting that the sorting of residual waste can further increase the secondary materials amount. The utilisation of energy recovery to treat the low-grade waste allows the maximisation of waste diversion from landfill with a low production of hazardous ash. A preliminary economic balance has been carried out to define the gate fee of the waste management system that was in the range of 84-145 € t(-1) without including the separate collection cost. The cost of door-by-door separate collection, designed to ensure the collection of five separate streams, resulted in 250 € t(-1) ±30%. © The Author(s) 2015.

  14. Performance Test on Compression Ignition Engine by Blending Ethanol and Waste Plastic Pyrolysis Oil with Cetane Additive

    Science.gov (United States)

    Padmanabhan, S.; Ganesan, S.; Jeswin Arputhabalan, J.; Chithrala, Varun; Ganesh Bairavan, P.

    2017-05-01

    The demand for diesel fuel is higher than that of petrol throughout the world hence seeking alternative to mineral diesel is a natural choice. Alternative fuels should be easily available at lower cost, environment friendly and fulfill energy needs without modifying engine’s operational parameters. Waste to energy is the trend in the selection of alternate fuels. In this work, Waste Plastic Pyrolysis oil (WPPO), Ethanol, Diesel blend with Cetane additive has been attempted as an alternative fuel. A Twin cylinder, Direct Injection engine was used to assess the engine performance and emission characteristics of waste plastic pyrolysis oil with cetane additive. Experimental results of blended plastic fuel and diesel fuel were compared.

  15. Hanford Immobilized Low Activity Waste (ILAW) Performance Assessment 2001 Version [Formerly DOE/RL-97-69] [SEC 1 & 2

    Energy Technology Data Exchange (ETDEWEB)

    MANN, F.M.

    2000-08-01

    The Hanford Immobilized Low-Activity Waste Performance Assessment examines the long-term environmental and human health effects associated with the planned disposal of the vitrified low-activity fraction of waste presently contained in Hanford Site tanks. The tank waste is the byproduct of separating special nuclear materials from irradiated nuclear fuels over the past 50 years. This waste is stored in underground single- and double-shell tanks. The tank waste is to be retrieved, separated into low-activity and high-level fractions, and then immobilized by vitrification. The US. Department of Energy (DOE) plans to dispose of the low-activity fraction in the Hanford Site 200 East Area. The high-level fraction will be stored at the Hanford Site until a national repository is approved. This report provides the site-specific long-term environmental information needed by the DOE to modify the current Disposal Authorization Statement for the Hanford Site that would allow the following: construction of disposal trenches; and filling of these trenches with ILAW containers and filler material with the intent to dispose of the containers.

  16. Stabilization/solidification of synthetic Nigerian drill cuttings

    African Journals Online (AJOL)

    EJIRO

    , Port Harcourt, Rivers State, Nigeria. Accepted 20 January ... the contaminants into a form which is less soluble, mobile or toxic. Solidification/Stabilization has many advantages since it requires minimal energy input and results in minimal ...

  17. Non-equilibrium solidification of undercooled droplets during ...

    Indian Academy of Sciences (India)

    equilibrium solidification of ... A mathematical model, based on classical theory of heterogeneous nucleation and volume separation of nucleants among droplets size distribution, is described to predict undercooling of droplets. Newtonian heat flow ...

  18. Effect Of Natural Convection On Directional Solidification Of Pure Metal

    Directory of Open Access Journals (Sweden)

    Skrzypczak T.

    2015-06-01

    Full Text Available The paper is focused on the modeling of the directional solidification process of pure metal. During the process the solidification front is sharp in the shape of the surface separating liquid from solid in three dimensional space or a curve in 2D. The position and shape of the solid-liquid interface change according to time. The local velocity of the interface depends on the values of heat fluxes on the solid and liquid sides. Sharp interface solidification belongs to the phase transition problems which occur due to temperature changes, pressure, etc. Transition from one state to another is discontinuous from the mathematical point of view. Such process can be identified during water freezing, evaporation, melting and solidification of metals and alloys, etc.

  19. Sludge accumulation and distribution impact the hydraulic performance in waste stabilisation ponds.

    Science.gov (United States)

    Coggins, Liah X; Ghisalberti, Marco; Ghadouani, Anas

    2017-03-01

    Waste stabilisation ponds (WSPs) are used worldwide for wastewater treatment, and throughout their operation require periodic sludge surveys. Sludge accumulation in WSPs can impact performance by reducing the effective volume of the pond, and altering the pond hydraulics and wastewater treatment efficiency. Traditionally, sludge heights, and thus sludge volume, have been measured using low-resolution and labour intensive methods such as 'sludge judge' and the 'white towel test'. A sonar device, a readily available technology, fitted to a remotely operated vehicle (ROV) was shown to improve the spatial resolution and accuracy of sludge height measurements, as well as reduce labour and safety requirements. Coupled with a dedicated software package, the profiling of several WSPs has shown that the ROV with autonomous sonar device is capable of providing sludge bathymetry with greatly increased spatial resolution in a greatly reduced profiling time, leading to a better understanding of the role played by sludge accumulation in hydraulic performance of WSPs. The high-resolution bathymetry collected was used to support a much more detailed hydrodynamic assessment of systems with low, medium and high accumulations of sludge. The results of the modelling show that hydraulic performance is not only influenced by the sludge accumulation, but also that the spatial distribution of sludge plays a critical role in reducing the treatment capacity of these systems. In a range of ponds modelled, the reduction in residence time ranged from 33% in a pond with a uniform sludge distribution to a reduction of up to 60% in a pond with highly channelized flow. The combination of high-resolution measurement of sludge accumulation and hydrodynamic modelling will help in the development of frameworks for wastewater sludge management, including the development of more reliable computer models, and could potentially have wider application in the monitoring of other small to medium water bodies

  20. An introduction to the mechanics of performance assessment using examples of calculations done for the Waste Isolation Pilot Plant between 1990 and 1992. Revision

    Energy Technology Data Exchange (ETDEWEB)

    Rechard, R.P.

    1996-06-01

    This document provides an overview of the processes used to access the performance of the Waste Isolation Pilot Plant (WIPP). The quantitative metrics used in the performance-assessment (PA) process are those put forward in the Environmental Protection Agency`s Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, HIgh-LEvel and transuranic radioactive Wastes (40 CFR 191).

  1. Measurement and Evaluation of Heating Performance of Heat Pump Systems Using Wasted Heat from Electric Devices for an Electric Bus

    OpenAIRE

    Cho, Chung-Won; Lee, Ho-Seong; Won, Jong-Phil; Lee, Moo-Yeon

    2012-01-01

    The objective of this study is to investigate heating performance characteristics of a coolant source heat pump using the wasted heat from electric devices for an electric bus. The heat pump, using R-134a, is designed for heating a passengers’ compartment by using discharged energy from the coolant of electric devices, such as motors and inverters of the electric bus. The heating performance of the heat pump was tested by varying the operating parameters, such as outdoor temperature and volum...

  2. Alternatives for managing wastes from reactors and post-fission operations in the LWR fuel cycle. Volume 2. Alternatives for waste treatment

    Energy Technology Data Exchange (ETDEWEB)

    1976-05-01

    Volume II of the five-volume report is devoted to the description of alternatives for waste treatment. The discussion is presented under the following section titles: fuel reprocessing modifications; high-level liquid waste solidification; treatment and immobilization of chop-leach fuel bundle residues; treatment of noncombustible solid wastes; treatment of combustible wastes; treatment of non-high-level liquid wastes; recovery of transuranics from non-high-level wastes; immobilization of miscellaneous non-high-level wastes; volatile radioisotope recovery and off-gas treatment; immobilization of volatile radioisotopes; retired facilities (decontamination and decommissioning); and, modification and use of selected fuel reprocessing wastes. (JGB)

  3. Performance evaluation of the PITBULL{trademark} pump for the removal of hazardous waste

    Energy Technology Data Exchange (ETDEWEB)

    Hatchell, B.K.; Combs, W.H.; Hymas, C.R.; Powell, M.R.; Rinker, M.W.; White, M.

    1998-09-01

    One objective of the Waste Removal Project at the Department of Energy`s Savannah River Site (SRS) is to explore methods to successfully remove waste heels that will remain in the high-level waste tanks after bulk waste removal has been completed. Tank closure is not possible unless this residue is removed. As much as 151,000 liters of residue can remain after a conventional waste removal campaign. The waste heels can be comprised of sludge, zeolite, and silica. The heels are generally hardened or compacted insoluble particulate with relatively rapid settling velocities. A PITBULL{trademark} pump is being considered by SRS to retrieve sludge-type waste from Tank 19. Sections 1 through 4 of this report present the scope and objectives of the test program, describe the principles of operation of the PITBULL, and present the test approach, set-up, and instrumentation. Test results, including pumping rates with water and slurry, are provided in Section 5, along with considerations for remote operation. Conclusions and recommendations are provided in Section 6.

  4. Source team evaluation for radioactive low-level waste disposal performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Cowgill, M.G.; Sullivan, T.M. [Brookhaven National Lab., Upton, NY (United States)

    1993-01-01

    Information compiled on the low-level radioactive waste disposed at the three currently operating commercial disposal sites during the period 1987--1989 have been reviewed and processed in order to determine the total activity distribution in terms of waste stream, waste classification and waste form. The review identified deficiencies in the information currently being recorded on shipping manifests and the development of a uniform manifest is recommended (the NRC is currently developing a rule to establish a uniform manifest). The data from waste disposed during 1989 at one of the sites (Richland, WA) were more detailed than the data available during other years and at other sites, and thus were amenable to a more in-depth treatment. This included determination of the distribution of activity for each radionuclide by waste form, and thus enabled these data to be evaluated in terms of the specific needs for improved modeling of releases from waste packages. From the results, preliminary lists have been prepared of the isotopes which might be the most significant from the aspect of the development of a source term model.

  5. Solidification thermal parameters affecting the columnar-to-equiaxed transition

    OpenAIRE

    Siqueira, CA; Cheung, N; Garcia, A

    2002-01-01

    Experiments were conducted to analyze the columnar-to-equiaxed transition (CET) during the upward unsteady-state directional solidification of Al-Cu and Sn-Pb alloys, under different conditions of superheat and heat-transfer efficiencies at the metal/mold interface. A combined theoretical and experimental approach is developed to quantitatively determine the solidification thermal parameters: transient heat-transfer coefficients, tip growth rates, thermal gradients, and cooling rates. The obs...

  6. EFFECT OF FEEDING DINNING ROOM AND KITCHEN WASTE ON GROWTH PERFORMANCE OF GROWING PIGS

    Directory of Open Access Journals (Sweden)

    Guadalupe Ramírez Zúñiga

    2014-08-01

    Full Text Available This research used 41 growing backyard piglets (11.47 ± 1.2 kg BW fed for 22 d and assigned at random to three treatment (T groups, respectively (T1 to T3 with three repetitions. The proportion of commercial concentrate (CC to kitchen waste (DW was: T1, 100:0; T2, 50:50 and T3, 0:100. Diets contained: T1, 17.3, 13.6 and 16.3% CP and 3,321, 3,526 and 4,011 McCall/kg of ME, respectively. Weight gain, carcass characteristics, minerals and metabolites in blood serum were evaluated. The weight gain, slaughter weight, hot and cold carcass weight, hot and cold carcass yield, rib eye area and back fat thickness were not affected by DW (P> 0.05. The cuts of leg shoulder and rib were not affected by treatment (P> 0.05 for dry matter, ash and crude protein content. The increase in DW reduced ether extract content of leg and rib (P 0.05. The concentration of Ca decreased with DW inclusion (P 0.05. It is concluded that feeding with DW the backyard growing pig do not affect growth performance or quality of meat.

  7. Performance-assessment progress for the Rozan low-level waste disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Smietanski, L.; Mitrega, J.; Frankowski, Z. [Polish Geological Institute, Warsaw (Poland)] [and others

    1995-12-31

    The paper presents a condensed progress report on the performance assessment of Poland`s low-level waste disposal facility which is operating since 1961. The Rozan repository is of near-surface type with facilities which are the concrete fortifications built about 1910. Site characterization activities supplied information on regional geology, geohydrology, climatic and hydrologic conditions and terrain surface evolution due to geodynamic processes. Field surveys enabled to decode lithological, hydrogeological and geochemical site specific conditions. From the laboratory tests the data on groundwater chemistry and soil geochemical and hydraulic characteristics were obtained. The site geohydrologic main vulnerable element is the upmost directly endangered unconfined aquifer which is perched in relation to the region-wide hydraulic system. Heterogeneity of this system reflects in a wide range of hydraulic conductivity and thickness variations. It strongly affects velocity and flow directions. The chemistry of groundwater is unstable due to large sensitivity to external impacts. Modeling of the migration of the critical long-lived radionuclides Tc-99, U-238 and Pu-239 showed that the nearly 20 m thick unsaturated zone plays crucial role as an effective protective barrier. These radionuclides constitute minor part of the total inventory. Modeling of the development of the H-3 plume pointed out the role the macrodispersion plays in the unsaturated zone beneath the repository.

  8. Biodiesel production from waste cotton seed oil using low cost catalyst: Engine performance and emission characteristics

    Directory of Open Access Journals (Sweden)

    Duple Sinha

    2016-09-01

    Full Text Available Production of fatty acid methyl esters from waste cotton seed oil through transesterification was reported. The GC–MS analysis of WCCO oil was studied and the major fatty acids were found to be palmitic acid (27.76% and linoleic acid (42.84%. The molecular weight of the oil was 881.039 g/mol. A maximum yield of 92% biodiesel was reported when the reaction temperature, time, methanol/oil ratio and catalyst loading rate were 60 °C, 50 min, 12:1 and 3% (wt.%, respectively. The calcined egg shell catalyst was prepared and characterized. Partial purification of the fatty acid methyl esters was proposed for increasing the purity of the biodiesel and better engine performance. The flash point and the fire point of the biodiesel were found to be 128 °C and 136 °C, respectively. The Brake thermal efficiency of WCCO B10 biodiesel was 26.04% for maximum load, specific fuel consumption for diesel was 0.32 kg/kW h at maximum load. The use of biodiesel blends showed a reduction of carbon monoxide and hydrocarbon emissions and a marginal increase in nitrogen oxides (NOx emissions improved emission characteristics.

  9. Conceptual structure of the 1996 performance assessment for the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    HELTON,JON CRAIG; ANDERSON,D. RICHARD; BASABILVAZO,G.; JOW,HONG-NIAN; MARIETTA,MELVIN G.

    2000-05-18

    The conceptual structure of the 1996 performance assessment (PA) for the Waste Isolation Pilot Plant (WIPP) is described. This structure involves three basic entities (EN1, EN2, EN3): (1) EN1, a probabilistic characterization of the likelihood of different futures occurring at the WIPP site over the next 10,000 yr, (2) EN2, a procedure for estimating the radionuclide releases to the accessible environment associated with each of the possible futures that could occur at the WIPP site over the next 10,000 yr, and (3) EN3, a probabilistic characterization of the uncertainty in the parameters used in the definition of EN1 and EN2. In the formal development of the 1996 WIPP PA, EN1 is characterized by a probability space (S{sub st}, P{sub st}, p{sub st}) for stochastic (i.e., aleatory) uncertainly; EN2 is characterized by a function {line_integral} that corresponds to the models and associated computer programs used to estimate radionuclide releases; and EN3 is characterized by a probability space (S{sub su}, P{sub su}, p{sub su}) for subjective (i.e., epistemic) uncertainty. A high-level overview of the 1996 WIPP PA and references to additional sources of information are given in the context of (S{sub st}, P{sub st}, p{sub st}), {line_integral} and (S{sub su}, P{sub su}, p{sub su}).

  10. Effects of treatment time and temperature on the DC corona pretreatment performance of waste activated sludge

    Science.gov (United States)

    Yu, GAO; Ning, ZHAO; Yongdi, DENG; Minghang, WANG; Boxue, DU

    2018-02-01

    In order to improve the anaerobic digestion efficiency of waste activated sludge (WAS), a pretreatment procedure should be carried out so as to disrupt the microbial cell structure, thus releasing intracellular organic matters. In this paper, a corona discharge triggered by a DC voltage was employed to pre-treat WAS for various time periods under different temperatures. The magnitude of the DC voltage was 4 kV at both negative and positive polarities. The changes in the soluble chemical oxygen demand, phosphorus and nitrogen content, and pH value within the WAS were utilized to estimate the pretreatment performance of the DC corona. It was found that with increasing treatment time, the pretreatment efficiency tends to be reduced. With increased temperature, the pretreatment efficiency appears to be better. It is suggested that the oxidative species and the active particles generated in the corona discharge play an important role in disrupting the microbial cell structure, which is dependent upon the treatment time and the temperature.

  11. Engineering Properties and Microstructural Performance of Low Energy Super-Sulfated Cement Using Industrial Waste Anhydrite

    Directory of Open Access Journals (Sweden)

    Huang Tsung-Yuan

    2017-01-01

    Full Text Available This study aims at proposing the mix proportions of low energy super-sulfated cement (SSC concrete from industrial waste anhydrite from circulating fluidized bed combustion (CFBC fly ash (CFA as an alternative sulfate activator of ground granulated blast furnace slag (GGBFS/slag. The optimized mix proportion of the SSC was carried out by using mixture of different amounts of CFA in range of 25—45 wt.% and various quantities of ordinary Portland cement (OPC in range of 0 — 10 wt.% to trigger the hydration of slag. Experimental results showed that with the expected slump at values of 190 — 220 mm, the 28-day compressive strengths of the concrete with low energy SSC reached 43.69 MPa which can be feasibly applied for widely advanced construction materials. The OPC in range of 3 — 5 wt.% and 25 wt.% of CFA were considered as the optimum ingredients of the activator and was suggested to be used for fabricating the low energy SSC concrete with the good performance on compressive strength, dynamic Young’s modulus, UPV measurement, and stabilized change of length. The OPC additive up to 10 wt.% was encouraged to be used for producing the SSC concrete with significant reduction on creep.

  12. Combustion, Performance, and Emission Evaluation of a Diesel Engine with Biodiesel Like Fuel Blends Derived From a Mixture of Pakistani Waste Canola and Waste Transformer Oils

    Directory of Open Access Journals (Sweden)

    Muhammad Qasim

    2017-07-01

    Full Text Available The aim of this work was to study the combustion, performance, and emission characteristics of a 5.5 kW four-stroke single-cylinder water-cooled direct-injection diesel engine operated with blends of biodiesel-like fuel (BLF15, BLF20 & BLF25 obtained from a 50:50 mixture of transesterified waste transformer oil (TWTO and waste canola oil methyl esters (WCOME with petroleum diesel. The mixture of the waste oils was named as biodiesel-like fuel (BLF.The engine fuelled with BLF blends was evaluated in terms of combustion, performance, and emission characteristics. FTIR analysis was carried out to know the functional groups in the BLF fuel. The experimental results revealed the shorter ignition delay and marginally higher brake specific fuel consumption (BSFC, brake thermal efficiency (BTE and exhaust gas temperature (EGT values for BLF blends as compared to diesel. The hydrocarbon (HC and carbon monoxide (CO emissions were decreased by 10.92–31.17% and 3.80–6.32%, respectively, as compared to those of diesel fuel. Smoke opacity was significantly reduced. FTIR analysis has confirmed the presence of saturated alkanes and halide groups in BLF fuel. In comparison to BLF20 and BLF25, the blend BLF15 has shown higher brake thermal efficiency and lower fuel consumption values. The HC, CO, and smoke emissions of BLF15 were found lower than those of petroleum diesel. The fuel blend BLF15 is suggested to be used as an alternative fuel for diesel engines without any engine modification.

  13. Integration of PFLOTRAN into Waste Isolation Pilot Plant Performance Assessment and Human Borehole Intrusion Cases

    Science.gov (United States)

    Park, H.

    2016-12-01

    The Waste Isolation Pilot Plant (WIPP), located in southeastern New Mexico, has been developed by the U.S. Department of Energy (DOE) for the deep geologic disposal of transuranic (TRU) waste. WIPP performance assessment (PA) calculations estimate the probability and consequence of potential radionuclide releases from the repository to the accessible environment arising from events and processes that could occur over the 10,000 year regulatory period. The conceptual model estimates three possible cases and the combinations of these cases: 1) undisturbed condition of the repository, 2) human borehole intrusion condition that penetrates the repository, and 3) human borehole intrusion that penetrates pressurized brine underlying the repository. This presentation demonstrates a simple proof-of-concept model for human borehole intrusion scenarios in fully saturated domain using PFLOTRAN. One simulation demonstrates a near hydrostatic condition of pressurized brine below the repository releasing pressure due to borehole intrusion and the other illustrates a lithostatic condition of pressurized brine. The result of these simulations are completely irrelevant to the real repository simulation; however, it shows the possibility to apply on a true-scale repository simulations. Not only these simulations are important for PA results, but PFLOTRAN also must be integrated with the rest of PA system. WIPP PA mainly consists of ten codes and PFLOTRAN may replace up to the duties of five codes for flow and reactive transport calculations. This presentation illustrates the complexity and potentials of integrating PFLOTRAN into WIPP PA. For example, PFLOTRAN uses HDF5 binary files; thus, data transfer format must be changed from CAMDAT binary files which are used in current WIPP PA. Pre-process of simulations are being developed to retrieve parameters from WIPP databases, apply algebraic calculations to meet criteria of PFLOTRAN input, and populate related input files. Post

  14. Waste Management Facilities Cost Information Report

    Energy Technology Data Exchange (ETDEWEB)

    Feizollahi, F.; Shropshire, D.

    1992-10-01

    The Waste Management Facility Cost Information (WMFCI) Report, commissioned by the US Department of Energy (DOE), develops planning life-cycle cost (PLCC) estimates for treatment, storage, and disposal facilities. This report contains PLCC estimates versus capacity for 26 different facility cost modules. A procedure to guide DOE and its contractor personnel in the use of estimating data is also provided. Estimates in the report apply to five distinctive waste streams: low-level waste, low-level mixed waste, alpha contaminated low-level waste, alpha contaminated low-level mixed waste, and transuranic waste. The report addresses five different treatment types: incineration, metal/melting and recovery, shredder/compaction, solidification, and vitrification. Data in this report allows the user to develop PLCC estimates for various waste management options.

  15. Decommissioning and safety issues of liquid-mercury waste generated from high power spallation sources with particle accelerators

    CERN Document Server

    Chiriki, S; Odoj, R; Moormann, R; Hinssen, H. K; Bukaemskiy, A

    2009-01-01

    Large spallation sources are intended to be constructed in Europe (EURISOL nuclear physics facility and ESS-European Spallation Source). These facilities accumulate more than 20 metric tons of irradiated mercury in the target, which has to be treated as highly radioactive and chemo-toxic waste. Because solids are the only appropriate (immobile) form for this radiotoxic and toxic type of waste solidification is required for irradiated mercury. Our irradiation experimental studies on mercury waste revealed that mercury sulfide is a reasonable solid for disposal and shows larger stability in assumed accidents with water ingress in a repository compared to amalgams. For preparation of mercury sulfide a wet process is more suitable than a dry one. It is easier to perform under hot cell conditions and allows complete Hg-conversion. Embedding HgS in a cementitious matrix increases its stability.

  16. Experimental Determination of the Primary Solidification Phase dependency on the solidification velocity for 17 different austenitic stainless steel compositions

    DEFF Research Database (Denmark)

    Laursen, Birthe Nørgaard; Olsen, Flemming Ove; Yardy, John

    1997-01-01

    , the primary solidification phase is found to change from ferrite to austenite.A novel laser remelting technique has been modified to enable the transition velocity for laser welded austenitic stainless steels to be deermined experimentally and on the basis of results from 17 different alloy compositions......When studying laser welding of austenitic stainless steel, hot cracking is frequently observed. To prevent hot cracking in laser welded stainless steel it is advantageous to obtain primary solidification of the ferrite phase that subsequently, on cooling, transforms in the solid state...... to the austenite phase.Most stainless steels are weldable by conventional welding techniques. However, during laser weldng the solidification velocities can be very much higher than by conventional welding techniques. By increasing the solidification velocity to a critical value known as the transition velocity...

  17. Interpretations of Tracer Tests Performed in the Culebra Dolomite at the Waste Isolation Pilot Plant Site

    Energy Technology Data Exchange (ETDEWEB)

    MEIGS,LUCY C.; BEAUHEIM,RICHARD L.; JONES,TOYA L.

    2000-08-01

    This report provides (1) an overview of all tracer testing conducted in the Culebra Dolomite Member of the Rustler Formation at the Waste Isolation Pilot Plant (WPP) site, (2) a detailed description of the important information about the 1995-96 tracer tests and the current interpretations of the data, and (3) a summary of the knowledge gained to date through tracer testing in the Culebra. Tracer tests have been used to identify transport processes occurring within the Culebra and quantify relevant parameters for use in performance assessment of the WIPP. The data, especially those from the tests performed in 1995-96, provide valuable insight into transport processes within the Culebra. Interpretations of the tracer tests in combination with geologic information, hydraulic-test information, and laboratory studies have resulted in a greatly improved conceptual model of transport processes within the Culebra. At locations where the transmissivity of the Culebra is low (< 4 x 10{sup -6} m{sup 2}/s), we conceptualize the Culebra as a single-porosity medium in which advection occurs largely through the primary porosity of the dolomite matrix. At locations where the transmissivity of the Culebra is high (> 4 x 10{sup -6} m{sup 2}/s), we conceptualize the Culebra as a heterogeneous, layered, fractured medium in which advection occurs largely through fractures and solutes diffuse between fractures and matrix at multiple rates. The variations in diffusion rate can be attributed to both variations in fracture spacing (or the spacing of advective pathways) and matrix heterogeneity. Flow and transport appear to be concentrated in the lower Culebra. At all locations, diffusion is the dominant transport process in the portions of the matrix that tracer does not access by flow.

  18. Performance assessment for the disposal of low-level waste in the 200 West Area Burial Grounds

    Energy Technology Data Exchange (ETDEWEB)

    Wood, M.I.; Khaleel, R.; Rittmann, P.D.; Lu, A.H.; Finfrock, S.H.; DeLorenzo, T.H. [Westinghouse Hanford Co., Richland, WA (United States); Serne, R.J.; Cantrell, K.J. [Pacific Northwest Lab., Richland, WA (United States)

    1995-06-01

    This document reports the findings of a performance assessment (PA) analysis for the disposal of solid low-level radioactive waste (LLW) in the 200 West Area Low-Level Waste Burial Grounds (LLBG) in the northwest corner of the 200 West Area of the Hanford Site. This PA analysis is required by US Department of Energy (DOE) Order 5820.2A (DOE 1988a) to demonstrate that a given disposal practice is in compliance with a set of performance objectives quantified in the order. These performance objectives are applicable to the disposal of DOE-generated LLW at any DOE-operated site after the finalization of the order in September 1988. At the Hanford Site, DOE, Richland Operations Office (RL) has issued a site-specific supplement to DOE Order 5820.2A, DOE-RL 5820.2A (DOE 1993), which provides additiona I ce objectives that must be satisfied.

  19. Geopolymers with a high percentage of bottom ash for solidification/immobilization of different toxic metals

    Energy Technology Data Exchange (ETDEWEB)

    Boca Santa, Rozineide A. Antunes, E-mail: roosebs@gmail.com; Soares, Cíntia; Riella, Humberto Gracher

    2016-11-15

    Highlights: • Geopolymers from bottom ash and metakaolin (BA/M). • Solidification/immobilization (S/I) waste of heavy metals. • Activators: Sodium hydroxide (NaOH), potassium hydroxide (KOH) and sodium silicate (Na{sub 2}SiO{sub 3}). - Abstract: Geopolymers are produced using alkali-activated aluminosilicates, either as waste or natural material obtained from various sources. This study synthesized geopolymers from bottom ash and metakaolin (BA/M) in a 2:1 wt ratio to test the solidification/immobilization (S/I) properties of heavy metals in geopolymer matrices, since there is very little research using BA in this type of matrices. Therefore, a decision was made to use more than 65% of BA in geopolymer synthesis with and without the addition of heavy metals. The S/I tests with metals used 10, 15 and 30 ml of a waste solution after pickling of printed circuit boards containing metals, including Pb, Cr, Cu, Fe, Sn, As and Ni, in different proportions. As alkali activator, the NaOH and KOH were used in the concentrations of 8 and 12 M in the composition of Na{sub 2}SiO{sub 3} in 1:2 vol ratios. To test S/I efficiency, tests were conducted to obtain the leached and solubilized extract. The analysis was carried out through X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Scanning Electron Microscope (SEM), Energy-Dispersive X-Ray Spectroscopy (EDS) and compressive strength tests. The geopolymer showed a high degree of S/I of the metals; in some samples, the results reached nearly 100%.

  20. Separation Mechanism of Fatty Acids from Waste Cooking Oil and Its Flotation Performance in Iron Ore Desiliconization

    Directory of Open Access Journals (Sweden)

    Wenda Guo

    2017-12-01

    Full Text Available Using the mixed fatty acids (MFA produced by waste cooking oil as flotation collectors directly, the flotation effect is usually not satisfactory, especially at lower temperature, which may be due to the presence of large amounts of saturated fatty acids. In this study, waste cooking oil was separated into saturated fatty acids (SFA and unsaturated fatty acids (UFA. The separation mechanism was studied by molecular simulation based on quantum and molecular mechanics. SFA and UFA were analyzed by iodine value, melting point measurement and Fourier transform infrared (FT-IR spectroscopy to check the result of the separation. The micro-flotation and bench-scale flotation tests were performed to investigate the flotation differences between SFA and UFA. The results showed that the poor flotation performance of waste cooking oil was due to the large amount of SFA in presence. If the SFA was separated out, the TFe grade and recovery of the flotation concentrates would be increased by 4.09 and 2.70 percentage points, respectively and the SiO2 grade would be 4.03 percentage points lower at the same time. This study would provide technical supports and theoretical guidance for the waste cooking oil application in the field of mineral processing.

  1. Diesel engine performance and exhaust emission analysis using waste cooking biodiesel fuel with an artificial neural network

    Energy Technology Data Exchange (ETDEWEB)

    Ghobadian, B.; Rahimi, H.; Nikbakht, A.M.; Najafi, G. [Tarbiat Modares University, P.O. Box 14115-111, Tehran (Iran); Yusaf, T.F. [University of Southern Queensland, Toowoomba 4350 QLD (Australia)

    2009-04-15

    This study deals with artificial neural network (ANN) modeling of a diesel engine using waste cooking biodiesel fuel to predict the brake power, torque, specific fuel consumption and exhaust emissions of the engine. To acquire data for training and testing the proposed ANN, a two cylinders, four-stroke diesel engine was fuelled with waste vegetable cooking biodiesel and diesel fuel blends and operated at different engine speeds. The properties of biodiesel produced from waste vegetable oil was measured based on ASTM standards. The experimental results revealed that blends of waste vegetable oil methyl ester with diesel fuel provide better engine performance and improved emission characteristics. Using some of the experimental data for training, an ANN model was developed based on standard Back-Propagation algorithm for the engine. Multi layer perception network (MLP) was used for non-linear mapping between the input and output parameters. Different activation functions and several rules were used to assess the percentage error between the desired and the predicted values. It was observed that the ANN model can predict the engine performance and exhaust emissions quite well with correlation coefficient (R) 0.9487, 0.999, 0.929 and 0.999 for the engine torque, SFC, CO and HC emissions, respectively. The prediction MSE (Mean Square Error) error was between the desired outputs as measured values and the simulated values were obtained as 0.0004 by the model. (author)

  2. System Performance Testing of the Pulse-Echo Ultrasonic Instrument for Critical Velocity Determination during Hanford Tank Waste Transfer Operations - 13584

    Energy Technology Data Exchange (ETDEWEB)

    Denslow, Kayte M.; Bontha, Jagannadha R.; Adkins, Harold E.; Jenks, Jeromy W.J.; Hopkins, Derek F. [Pacific Northwest National Laboratory, Richland, Washington 99354 (United States); Thien, Michael G.; Kelly, Steven E.; Wooley, Theodore A. [Washington River Protection Solutions, Richland, Washington 99354 (United States)

    2013-07-01

    The delivery of Hanford double-shell tank waste to the Hanford Tank Waste Treatment and Immobilization Plant (WTP) is governed by specific Waste Acceptance Criteria that are identified in ICD 19 - Interface Control Document for Waste Feed. Waste must be certified as acceptable before it can be delivered to the WTP. The fluid transfer velocity at which solid particulate deposition occurs in waste slurry transport piping (critical velocity) is a key waste acceptance parameter that must be accurately characterized to determine if the waste is acceptable for transfer to the WTP. Washington River Protection Solutions and the Pacific Northwest National Laboratory have been evaluating the ultrasonic PulseEcho instrument since 2010 for its ability to detect particle settling and determine critical velocity in a horizontal slurry transport pipeline for slurries containing particles with a mean particle diameter of =14 micrometers (μm). In 2012 the PulseEcho instrument was further evaluated under WRPS' System Performance test campaign to identify critical velocities for slurries that are expected to be encountered during Hanford tank waste retrieval operations or bounding for tank waste feed. This three-year evaluation has demonstrated the ability of the ultrasonic PulseEcho instrument to detect the onset of critical velocity for a broad range of physical and rheological slurry properties that are likely encountered during the waste feed transfer operations between the Hanford tank farms and the WTP. (authors)

  3. System Performance Testing of the Pulse-Echo Ultrasonic Instrument for Critical Velocity Determination during Hanford Tank Waste Transfer Operations - 13584

    Energy Technology Data Exchange (ETDEWEB)

    Denslow, Kayte M.; Bontha, Jagannadha R.; Adkins, Harold E.; Jenks, Jeromy WJ; Hopkins, Derek F.; Thien, Michael G.; Kelly, Steven E.; Wooley, Theodore A.

    2013-06-01

    The delivery of Hanford double-shell tank waste to the Hanford Tank Waste Treatment and Immobilization Plant (WTP) is governed by specific Waste Acceptance Criteria that are identified in ICD 19 - Interface Control Document for Waste Feed. Waste must be certified as acceptable before it can be delivered to the WTP. The fluid transfer velocity at which solid particulate deposition occurs in waste slurry transport piping (critical velocity) is a key waste acceptance parameter that must be accurately characterized to determine if the waste is acceptable for transfer to the WTP. Washington River Protection Solutions and the Pacific Northwest National Laboratory have been evaluating the ultrasonic PulseEcho instrument since 2010 for its ability to detect particle settling and determine critical velocity in a horizontal slurry transport pipeline for slurries containing particles with a mean particle diameter of ≥14 micrometers (μm). In 2012 the PulseEcho instrument was further evaluated under WRPS’ System Performance test campaign to identify critical velocities for slurries that are expected to be encountered during Hanford tank waste retrieval operations or bounding for tank waste feed. This three-year evaluation has demonstrated the ability of the ultrasonic PulseEcho instrument to detect the onset of critical velocity for a broad range of physical and rheological slurry properties that are likely encountered during the waste feed transfer operations between the Hanford tank farms and the WTP.

  4. Exposure Scenarios and Unit Dose Factors for the Hanford Immobilized Low Activity Tank Waste Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    RITTMANN, P.D.

    1999-12-29

    Exposure scenarios are defined to identify potential pathways and combinations of pathways that could lead to radiation exposure from immobilized tank waste. Appropriate data and models are selected to permit calculation of dose factors for each exposure

  5. Technical Exchange on Improved Design and Performance of High Level Waste Melters - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    SK Sundaram; ML Elliott; D Bickford

    1999-11-19

    SIA Radon is responsible for management of low- and intermediate-level radioactive waste (LILW) produced in Central Russia. In cooperation with Minatom organizations Radon carries out R and D programs on treatment of simulated high level waste (HLW) as well. Radon scientists deal with a study of materials for LILW, HLW, and Nuclear Power Plants (NPP) wastes immobilization, and development and testing of processes and technologies for waste treatment and disposal. Radon is mostly experienced in LILW vitrification. This experience can be carried over to HLW vitrification especially in field of melting systems. The melter chosen as a basic unit for the vitrification plant is a cold crucible. Later on Radon experience in LILW vitrification as well as our results on simulated HLW vitrification are briefly described.

  6. Municipal Solid Waste Landfills: New Source Performance Standards (NSPS), Emission Guidelines (EG) and Compliance Times

    Science.gov (United States)

    learn about the NSPS for municipal solid waste landfills by reading the rule summary, rule history, code of federal regulations text, fact sheets, background information documents, related rules and compliance information.

  7. Solid secondary waste testing for maintenance of the Hanford Integrated Disposal Facility Performance Assessment - FY 2017

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, Ralph L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Seitz, Roger R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dixon, Kenneth L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-08-01

    The Waste Treatment and Immobilization Plant (WTP) at Hanford is being constructed to treat 56 million gallons of radioactive waste currently stored in underground tanks at the Hanford site. Operation of the WTP will generate several solid secondary waste (SSW) streams including used process equipment, contaminated tools and instruments, decontamination wastes, high-efficiency particulate air filters (HEPA), carbon adsorption beds, silver mordenite iodine sorbent beds, and spent ion exchange resins (IXr) all of which are to be disposed in the Integrated Disposal Facility (IDF). An applied research and development program was developed using a phased approach to incrementally develop the information necessary to support the IDF PA with each phase of the testing building on results from the previous set of tests and considering new information from the IDF PA calculations. This report contains the results from the exploratory phase, Phase 1 and preliminary results from Phase 2. Phase 3 is expected to begin in the fourth quarter of FY17.

  8. Modeling and Performance of Waste Tires as Media in Fixed Bed Sequence Batch Reactor

    Directory of Open Access Journals (Sweden)

    Zahra Derakhshan

    2016-12-01

    Results: The maximum removal efficiencies of dissolved chemical oxygen demand for FBSBR and SBR reactors were 98.3 % and 97.9 %, respectively. In addition, Stover-Kincannon model provided a very suitable fitness (R2   > 0.99 for loading the bioreactor FBSBR. Conclusion: According to the results, not only waste tires can be reused, but also these wastes can be employed as a proper biological bed in wastewater refineries to improve their efficiency.

  9. Directional Solidification and Mechanical Properties of NiAl-NiAlTa Alloys

    Science.gov (United States)

    Johnson, D. R.; Chen, X. F.; Oliver, B. F.; Noebe, R. D.; Whittenberger, J. D.

    1995-01-01

    Directional solidification of eutectic alloys is a promising technique for producing in-situ composite materials exhibiting a balance of properties. Consequently, the microstructure, creep strength and fracture toughness of directionally solidified NiAl-NiAlTa alloys were investigated. Directional solidification was performed by containerless processing techniques to minimize alloy contamination. The eutectic composition was found to be NiAl-15.5 at% Ta and well-aligned microstructures were produced at this composition. A near-eutectic alloy of NiAl-14.5Ta was also investigated. Directional solidification of the near-eutectic composition resulted in microstructures consisting of NiAl dendrites surrounded by aligned eutectic regions. The off-eutectic alloy exhibited promising compressive creep strengths compared to other NiAl-based intermetallics, while preliminary testing indicated that the eutectic alloy was competitive with Ni-base single crystal superalloys. The room temperature toughness of these two-phase alloys was similar to that of polycrystalline NiAl even with the presence of the brittle Laves phase NiAlTa.

  10. Onset of solid state mantle convection and mixing during magma ocean solidification

    Science.gov (United States)

    Maurice, Maxime; Tosi, Nicola; Samuel, Henri; Plesa, Ana-Catalina; Hüttig, Christian; Breuer, Doris

    2017-04-01

    The fractional crystallization of a magma ocean can cause the formation of a compositional layering that can play a fundamental role for the subsequent long-term dynamics of the interior, for the evolution of geochemical reservoirs, and for surface tectonics. In order to assess to what extent primordial compositional heterogeneities generated by magma ocean solidification can be preserved, we investigate the solidification of a whole-mantle Martian magma ocean, and in particular the conditions that allow solid state convection to start mixing the mantle before solidification is completed. To this end, we performed 2-D numerical simulations in a cylindrical geometry. We treat the liquid magma ocean in a parametrized way while we self-consistently solve the conservation equations of thermochemical convection in the growing solid cumulates accounting for pressure-, temperature- and, where it applies, melt-dependent viscosity as well as parametrized yield stress to account for plastic yielding. By testing the effects of different cooling rates and convective vigor, we show that for a lifetime of the liquid magma ocean of 1 Myr or longer, the onset of solid state convection prior to complete mantle crystallization is likely and that a significant part of the compositional heterogeneities generated by fractionation can be erased by efficient mantle mixing.

  11. Experimental Study on Melting and Solidification of Phase Change Material Thermal Storage

    Science.gov (United States)

    Ambarita, H.; Abdullah, I.; Siregar, C. A.; Siregar, R. E. T.; Ronowikarto, A. D.

    2017-03-01

    Melting and solidification process of Phase Change Materials (PCMs) are investigated experimentally. The tested PCMs are Paraffin wax and Steric acid which typically used for solar water heater. The objective is to explore the characteristics of the PCM when it is being melted and solidified. The experiments are performed in a glass box. One side of the box wall is heated while the opposite wall is kept constant and other walls are insulated. Temperature of the heated wall are kept constant at 80°C, 85°C, and 90°C, respectively. Every experiment is carried out for 600 minutes. Temperatures are recorded and the melting and solidification processes are pictured by using camera. The results show that the melting process starts from the upper part of the thermal storage. In the solidification process, it starts from the lower part of the thermal storage. As a thermal energy storage, Paraffin wax is better than Steric acid. This is because Paraffin wax can store more energy. At heat source temperature of 90°C, thermal energy stored by Paraffin wax and Stearic acid is 61.84 kJ and 57.39 kJ, respectively. Thus it is better to used Paraffin wax in the solar water heater as thermal energy storage.

  12. Influence of cooling rate on microstructure formation during rapid solidification of binary TiAl alloys

    Energy Technology Data Exchange (ETDEWEB)

    Kenel, C., E-mail: Christoph.Kenel@empa.ch; Leinenbach, C.

    2015-07-15

    Highlights: • Rapid solidification studies with varying cooling rates were realized for Ti–Al. • Experiments were combined with finite element simulations of heat transfer. • The resulting microstructure of Ti–Al alloys is strongly dependent on the Al content. • The microstructure and phase transformation behavior can be predicted. • The method allows alloy development for processes involving rapid solidification. - Abstract: Titanium aluminides as structural intermetallics are possible candidates for a potential weight reduction and increased performance of high temperature components. A method for the characterization of the microstructure formation in rapidly solidified alloys was developed and applied for binary Ti–(44–48)Al (at.%). The results show a strong dependency of the microstructure on the Al content at cooling rates between 6 ⋅ 10{sup 2} and 1.5 ⋅ 10{sup 4} K s{sup −1}. The formation of α → α{sub 2} ordering, lamellar α{sub 2} + γ colonies and interdendritic TiAl γ-phase were observed, depending on the Al amount. Based on thermodynamic calculations the observed microstructure can be explained using the CALPHAD approach taking into account the non-equilibrium conditions. The presented method provides a useful tool for alloy development for processing techniques involving rapid solidification with varying cooling rates.

  13. Solidification and immobilization of MSWI fly ash through aluminate geopolymerization: Based on partial charge model analysis.

    Science.gov (United States)

    Zheng, Lei; Wang, Wei; Gao, Xingbao

    2016-12-01

    This study presents an integrated synopsis of the solidification and immobilization mechanisms of fly ash-based geopolymers. A rational analysis of the ion reactions involved in geopolymerization was conducted using the partial charge model (PCM). The following conclusions were obtained: (1) heavy metal cations cannot be immobilized as counter cations through exchange with Na(+); (2) isomorphous substitution of heavy metals in the geopolymer can be expected from the condensation reaction between the hydrolyzed heavy metal species and aluminosilicate; (3) the hydrolyzed species condensation could result in solidification and immobilization and be promoted by aluminates; and (4) a geopolymer with the highest immobilization and solidification efficiency can be obtained at an intermediate pH value. The partial charges on the framework of Si, Al, and O in the primary building blocks of aluminosilicate and heavy metal-doped aluminosilicate were confirmed through XPS and (29)Si NMR spectroscopy analyses. The effects of activator dosage and types on fly ash-based geopolymers were also investigated, and the results verify the PCM analysis. A geopolymer with the highest strength was produced at an intermediate alkaline dosage. Silicate or aluminate introduced into the activator improved the strength and immobilization efficiency, and aluminate exhibited better performance. Heavy metals bound to the exchangeable or acid-soluble fraction were transformed into aluminosilicate species during geopolymerization. Copyright © 2016. Published by Elsevier Ltd.

  14. Performance of A Horizontal Cylinder Type Rotary Dryer for Drying Process ofOrganic Compost from Solid Waste Cocoa Pod

    Directory of Open Access Journals (Sweden)

    Sukrisno Widyotomo

    2008-07-01

    Full Text Available Cocoa pod husk is the bigest component of cocoa pod, about 70% of total ht of mature pod, and to potentially used as organic compost source. Poten tial solid waste of cocoa pod husk from a cocoa processing centre is about 15— 22 m3/ha/year. A cocoa plantation needs about 20—30 ton/ha/year of organic matters. One of important steps in compos processing technology of cocoa pod solid waste is drying process. Organic compost with 20% moisture content is more easy in handling, application, storage and distribution. Indonesian Coffee and Cocoa Research Institute has designed and tested a horizontal cylinder type rotary dryer for drying process of organic compos from solid waste cocoa pod with kerosene burner as energy sources. The objective of this research is to study performance of a horizontal cylinder type rotary dryer using kerosene burner as energy source for drying process of organic compost from solid waste cocoa pod. The material used was solid waste cocoa pod with 70—75% moisture content (wet basis, 70% size particle larger than 4.76 mm, and 30% size particle less than 4.76 mm, 690—695 kg/m3 bulk density. Drying process temperatures treatment were 60OC, 80OC, and 100OC, and cylinder rotary speed treatments were 7 rpm, 10 rpm, dan 16 rpm. The results showed that dryer had capacity about 102—150 kg/h depend on drying temperature and cylinder rotary speed. Optimum operation condition at 100OC drying temperature, and 10 rpm cylinder rotary speed with drying time to reach final moisture content of 20% was 1,6 h, capacity 136,14 kg/ h, bulk density 410 kg/m3, porocity 45,15%, kerosene consumption as energy source was 2,57 l/h, and drying efficiency 68,34%. Key words : cocoa, drying, rotary dryer, compost, waste

  15. Enhancement of biogas production from food waste and sewage sludge - Environmental and economic life cycle performance.

    Science.gov (United States)

    Eriksson, Ola; Bisaillon, Mattias; Haraldsson, Mårten; Sundberg, Johan

    2016-06-15

    Management of municipal solid waste is an efficient method to increase resource efficiency, as well as to replace fossil fuels with renewable energy sources due to that (1) waste to a large extent is renewable as it consists of food waste, paper, wood etc. and (2) when energy and materials are recovered from waste treatment, fossil fuels can be substituted. In this paper results from a comprehensive system study of future biological treatment of readily degradable waste in two Swedish regions are presented. Different collection and separation systems for food waste in households have been applied as well as technical improvements of the biogas process as to reduce environmental impact. The results show that central sorting of a mixed fraction into recyclables, combustibles, biowaste and inert is a competitive option compared to source separation. Use of pellets is beneficial compared to direct spreading as fertiliser. Fuel pellets seem to be the most favourable option, which to a large extent depends on the circumstances in the energy system. Separation and utilisation of nitrogen in the wet part of the digestion residue is made possible with a number of technologies which decreases environmental impact drastically, however to a substantial cost in some cases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Performances of broiler supplemented with antibiotic and Morinda citrifolia waste as sources of bioactive compounds

    Directory of Open Access Journals (Sweden)

    I.A.K Bintang

    2008-03-01

    Full Text Available A study on the use of Zinc bacitracin antibiotic (ZnB and dried Morinda citrifolia waste as feed additive in broiler ration was conducted. Two hundred and sixteen day old chicks (DOC was allocated into 4 treatments: control; control + 50 ppm ZnB, and control + M. citrifolia waste at 2 levels (5 and 10 g/kg ration with 9 replications. Each replicatation consist of 6 birds. The treatments were allocated in a completely randomized design. Variables measured were feed intake, live weight, feed conversion ratio (FCR, percentages of carcass and internal organs (liver, gizard, abdominal fat, and thickness of intestine. The results showed that feed intake of M. citrifolia waste was significantly (P0.05 from that of control. The use of M. citrifolia waste (5 and 10 g/kg gave significantly lower (P0.05, but was significantly lower (P0,05 than that of control, control + antibiotic ZnB and M. citrifolia waste 5g/kg. It is concluded that the supplementation of M. citrifolia waste (5 g/kg could substitute ZnB to improve feed eficiency in broiler ration.

  17. Influence of gravity acceleration on macrosegregation and macrostructure during the unidirectional solidification of cast binary alloys: A numerical investigation

    Energy Technology Data Exchange (ETDEWEB)

    Nastac, L. [Concurrent Technologies Corp., Johnstown, PA (United States)

    1999-02-12

    A comprehensive numerical approach was developed for modeling of macrosegregation during the solidification of cast binary alloy. The model accounts for the competition between dendritic (columnar and equiaxed) and eutectic structures through the use of the solidification-kinetics modeling for fraction of solid evolution. Microsegregation analytical calculations are performed assuming molecular diffusion in both solid and liquid. The coupling between the macroscopic and microscopic calculations is accomplished with the micro-latent heat method. A numerical analysis was performed of the thermosolutal convection effects on macrosegregation and macrostructure (grain structure) during the solidification of a liquid Pb-10 wt.% Sn alloy cooled from below in terrestrial and low-gravity (g) environments. Below 0.01 g, the macrosegregation tendency is insignificant. Freckles, fingers (which are caused by plumes), and channels enriched in Sn as well as isolated pockets poor in Sn develop for 1 g and sufficiently low thermosolutal Rayleigh number. For the simulation conditions used in this work (e.g., high thermal gradients), small effects of the thermosolutal convection on the solidification macrostructure were observed.

  18. The Gunite and Associated Tanks Remediation Project Tank Waste Retrieval Performance and Lessons Learned, vol. 1 [of 2

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, BE

    2003-10-07

    The Gunite and Associated Tanks (GAAT) Remediation Project was the first of its kind performed in the United States. Robotics and remotely operated equipment were used to successfully transfer almost 94,000 gal of remote-handled transuranic sludge containing over 81,000 Ci of radioactive contamination from nine large underground storage tanks at the Oak Ridge National Laboratory (ORNL). The sludge was transferred with over 439,000 gal of radioactive waste supernatant and {approx}420,500 gal of fresh water that was used in sluicing operations. The GAATs are located in a high-traffic area of ORNL near a main thoroughfare. A phased and integrated approach to waste retrieval operations was used for the GAAT Remediation Project. The project promoted safety by obtaining experience from low-risk operations in the North Tank Farm before moving to higher-risk operations in the South Tank Farm. This approach allowed project personnel to become familiar with the tanks and waste, as well as the equipment, processes, procedures, and operations required to perform successful waste retrieval. By using an integrated approach to tank waste retrieval and tank waste management, the project was completed years ahead of the original baseline schedule, which resulted in avoiding millions of dollars in associated costs. This report is organized in two volumes. Volume 1 provides information on the various phases of the GAAT Remediation Project. It also describes the different types of equipment and how they were used. The emphasis of Volume 1 is on the description of the tank waste retrieval performance and the lessons learned during the GAAT Remediation Project. Volume 2 provides the appendixes for the report, which include the following information: (A) Background Information for the Gunite and Associated Tanks Operable Unit; (B) Annotated Bibliography; (C) Comprehensive Listing of the Sample Analysis Data from the GAAT Remediation Project; (D) GAAT Equipment Matrix; and (E) Vendor List

  19. An Evaluation of Long-Term Performance of Liner Systems for Low-Level Waste Disposal Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Arthur S. Rood; Annette L. Schafer; A. Jeffrey Sondrup

    2011-03-01

    Traditional liner systems consisting of a geosynthetic membrane underlying a waste disposal facility coupled with a leachate collection system have been proposed as a means of containing releases of low-level radioactive waste within the confines of the disposal facility and thereby eliminating migration of radionuclides into the vadose zone and groundwater. However, this type of hydraulic containment liner system is only effective as long as the leachate collection system remains functional or an overlying cover limits the total infiltration to the volumetric pore space of the disposal system. If either the leachate collection system fails, or the overlying cover becomes less effective during the 1,000’s of years of facility lifetime, the liner may fill with water and release contaminated water in a preferential or focused manner. If the height of the liner extends above the waste, the waste will become submerged which could increase the release rate and concentration of the leachate. If the liner extends near land surface, there is the potential for contamination reaching land surface creating a direct exposure pathway. Alternative protective liner systems can be engineered that eliminate radionuclide releases to the vadose zone during operations and minimizing long term migration of radionuclides from the disposal facility into the vadose zone and aquifer. Non-traditional systems include waste containerization in steel or composite materials. This type of system would promote drainage of clean infiltrating water through the facility without contacting the waste. Other alternatives include geochemical barriers designed to transmit water while adsorbing radionuclides beneath the facility. Facility performance for a hypothetical disposal facility has been compared for the hydraulic and steel containerization liner alternatives. Results were compared in terms of meeting the DOE Order 435.1 low-level waste performance objective of 25 mrem/yr all-pathways dose

  20. Performance and kinetic study of semi-dry thermophilic anaerobic digestion of organic fraction of municipal solid waste

    Energy Technology Data Exchange (ETDEWEB)

    Sajeena Beevi, B., E-mail: sajeenanazer@gmail.com [Department of Chemical Engineering, Govt. Engineering College, Thrissur, Kerala 680 009 (India); Madhu, G., E-mail: profmadhugopal@gmail.com [Division of Safety & Fire Engineering, School of Engineering, Cochin University of Science and Technology, Cochin, Kerala 682 022 (India); Sahoo, Deepak Kumar, E-mail: dksahoo@gmail.com [Division of Safety & Fire Engineering, School of Engineering, Cochin University of Science and Technology, Cochin, Kerala 682 022 (India)

    2015-02-15

    Highlights: • Performance of the reactor was evaluated by the degradation of volatile solids. • Biogas yield at the end of the digestion was 52.9 L/kg VS. • Value of reaction rate constant, k, obtained was 0.0249 day{sup −1}. • During the digestion 66.7% of the volatile solid degradation was obtained. - Abstract: Anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) is promoted as an energy source and waste disposal. In this study semi dry anaerobic digestion of organic solid wastes was conducted for 45 days in a lab-scale batch experiment for total solid concentration of 100 g/L for investigating the start-up performances under thermophilic condition (50 °C). The performance of the reactor was evaluated by measuring the daily biogas production and calculating the degradation of total solids and the total volatile solids. The biogas yield at the end of the digestion was 52.9 L/kg VS (volatile solid) for the total solid (TS) concentration of 100 g/L. About 66.7% of the volatile solid degradation was obtained during the digestion. A first order model based on the availability of substrate as the limiting factor was used to perform the kinetic studies of batch anaerobic digestion system. The value of reaction rate constant, k, obtained was 0.0249 day{sup −1}.

  1. Effect of Increasing Total Solids Contents on Anaerobic Digestion of Food Waste under Mesophilic Conditions: Performance and Microbial Characteristics Analysis

    Science.gov (United States)

    Jin, Jingwei; Dai, Xiaohu

    2014-01-01

    The total solids content of feedstocks affects the performances of anaerobic digestion and the change of total solids content will lead the change of microbial morphology in systems. In order to increase the efficiency of anaerobic digestion, it is necessary to understand the role of the total solids content on the behavior of the microbial communities involved in anaerobic digestion of organic matter from wet to dry technology. The performances of mesophilic anaerobic digestion of food waste with different total solids contents from 5% to 20% were compared and the microbial communities in reactors were investigated using 454 pyrosequencing technology. Three stable anaerobic digestion processes were achieved for food waste biodegradation and methane generation. Better performances mainly including volatile solids reduction and methane yield were obtained in the reactors with higher total solids content. Pyrosequencing results revealed significant shifts in bacterial community with increasing total solids contents. The proportion of phylum Chloroflexi decreased obviously with increasing total solids contents while other functional bacteria showed increasing trend. Methanosarcina absolutely dominated in archaeal communities in three reactors and the relative abundance of this group showed increasing trend with increasing total solids contents. These results revealed the effects of the total solids content on the performance parameters and the behavior of the microbial communities involved in the anaerobic digestion of food waste from wet to dry technologies. PMID:25051352

  2. Effect of increasing total solids contents on anaerobic digestion of food waste under mesophilic conditions: performance and microbial characteristics analysis.

    Directory of Open Access Journals (Sweden)

    Jing Yi

    Full Text Available The total solids content of feedstocks affects the performances of anaerobic digestion and the change of total solids content will lead the change of microbial morphology in systems. In order to increase the efficiency of anaerobic digestion, it is necessary to understand the role of the total solids content on the behavior of the microbial communities involved in anaerobic digestion of organic matter from wet to dry technology. The performances of mesophilic anaerobic digestion of food waste with different total solids contents from 5% to 20% were compared and the microbial communities in reactors were investigated using 454 pyrosequencing technology. Three stable anaerobic digestion processes were achieved for food waste biodegradation and methane generation. Better performances mainly including volatile solids reduction and methane yield were obtained in the reactors with higher total solids content. Pyrosequencing results revealed significant shifts in bacterial community with increasing total solids contents. The proportion of phylum Chloroflexi decreased obviously with increasing total solids contents while other functional bacteria showed increasing trend. Methanosarcina absolutely dominated in archaeal communities in three reactors and the relative abundance of this group showed increasing trend with increasing total solids contents. These results revealed the effects of the total solids content on the performance parameters and the behavior of the microbial communities involved in the anaerobic digestion of food waste from wet to dry technologies.

  3. Rate of solidification of aluminium casting in varying wall thickness of cylindrical metallic moulds

    Directory of Open Access Journals (Sweden)

    Katsina Christopher BALA

    2014-02-01

    Full Text Available The quality of final casting mainly depends on the rate of solidification as rapid solidification produces fine grains structures with better mechanical properties. The analysis of heat transfer during the casting and solidification of aluminium alloy as well as the experimental investigation of the rate of solidification in varying thicknesses of cylindrical metallic mould was carried out. The temperature variation with time of the casting was recorded from which cooling curves were obtained for the determination of solidification time of the cast. The results showed that as the cylindrical mould thickness increases the solidification time decreases due to the chilling effect of the mould.

  4. A review of technologies and performances of thermal treatment systems for energy recovery from waste.

    Science.gov (United States)

    Lombardi, Lidia; Carnevale, Ennio; Corti, Andrea

    2015-03-01

    The aim of this work is to identify the current level of energy recovery through waste thermal treatment. The state of the art in energy recovery from waste was investigated, highlighting the differences for different types of thermal treatment, considering combustion/incineration, gasification and pyrolysis. Also different types of wastes - Municipal Solid Waste (MSW), Refuse Derived Fuel (RDF) or Solid Refuse Fuels (SRF) and some typologies of Industrial Waste (IW) (sludge, plastic scraps, etc.) - were included in the analysis. The investigation was carried out mainly reviewing papers, published in scientific journals and conferences, but also considering technical reports, to gather more information. In particular the goal of this review work was to synthesize studies in order to compare the values of energy conversion efficiencies measured or calculated for different types of thermal processes and different types of waste. It emerged that the dominant type of thermal treatment is incineration associated to energy recovery in a steam cycle. When waste gasification is applied, the produced syngas is generally combusted in a boiler to generate steam for energy recovery in a steam cycle. For both the possibilities--incineration or gasification--co-generation is the mean to improve energy recovery, especially for small scale plants. In the case of only electricity production, the achievable values are strongly dependent on the plant size: for large plant size, where advanced technical solutions can be applied and sustained from an economic point of view, net electric efficiency may reach values up to 30-31%. In small-medium plants, net electric efficiency is constrained by scale effect and remains at values around 20-24%. Other types of technical solutions--gasification with syngas use in internally fired devices, pyrolysis and plasma gasification--are less common or studied at pilot or demonstrative scale and, in any case, offer at present similar or lower levels

  5. Performance test results of noninvasive characterization of Resource Conservation and Recovery Act surrogate waste by prompt gamma neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Gehrke, R.J.; Streier, G.G.

    1997-03-01

    During FY-96, a performance test was carried out with funding from the Mixed Waste Focus Area (MWFA) of the Department of Energy (DOE) to determine the noninvasive elemental assay capabilities of commercial companies for Resource Conservation and Recovery Act (RCRA) metals present in 8-gal drums containing surrogate waste. Commercial companies were required to be experienced in the use of prompt gamma neutron activation analysis (PGNAA) techniques and to have a prototype assay system with which to conduct the test assays. Potential participants were identified through responses to a call for proposals advertised in the Commerce Business Daily and through personal contacts. Six companies were originally identified. Two of these six were willing and able to participate in the performance test, as described in the test plan, with some subsidizing from the DOE MWFA. The tests were conducted with surrogate sludge waste because (1) a large volume of this type of waste awaits final disposition and (2) sludge tends to be somewhat homogeneous. The surrogate concentrations of the above RCRA metals ranged from {approximately} 300 ppm to {approximately} 20,000 ppm. The lower limit was chosen as an estimate of the expected sensitivity of detection required by noninvasive, pretreatment elemental assay systems to be of value for operational and compliance purposes and to still be achievable with state-of-the-art methods of analysis. The upper limit of {approximately} 20,000 ppm was chosen because it is the opinion of the author that assay above this concentration level is within current state-of-the-art methods for most RCRA constituents. This report is organized into three parts: Part 1, Test Plan to Evaluate the Technical Status of Noninvasive Elemental Assay Techniques for Hazardous Waste; Part 2, Participants` Results; and Part 3, Evaluation of and Comments on Participants` Results.

  6. Interface Pattern Selection in Directional Solidification

    Science.gov (United States)

    Trivedi, Rohit; Tewari, Surendra N.

    2001-01-01

    The central focus of this research is to establish key scientific concepts that govern the selection of cellular and dendritic patterns during the directional solidification of alloys. Ground-based studies have established that the conditions under which cellular and dendritic microstructures form are precisely where convection effects are dominant in bulk samples. Thus, experimental data can not be obtained terrestrially under pure diffusive regime. Furthermore, reliable theoretical models are not yet possible which can quantitatively incorporate fluid flow in the pattern selection criterion. Consequently, microgravity experiments on cellular and dendritic growth are designed to obtain benchmark data under diffusive growth conditions that can be quantitatively analyzed and compared with the rigorous theoretical model to establish the fundamental principles that govern the selection of specific microstructure and its length scales. In the cellular structure, different cells in an array are strongly coupled so that the cellular pattern evolution is controlled by complex interactions between thermal diffusion, solute diffusion and interface effects. These interactions give infinity of solutions, and the system selects only a narrow band of solutions. The aim of this investigation is to obtain benchmark data and develop a rigorous theoretical model that will allow us to quantitatively establish the physics of this selection process.

  7. Onset of sidebranching in directional solidification

    Science.gov (United States)

    Echebarria, Blas; Karma, Alain; Gurevich, Sebastian

    2010-02-01

    We use a computationally efficient phase-field formulation [B. Echebarria , Phys. Rev. E 70, 061604 (2004)] to investigate the origin and dynamics of sidebranching in directional solidification for realistic parameters of a dilute alloy previously studied experimentally [M. Gorgelin and A. Pocheau, Phys. Rev. E 57, 3189 (1998)]. Sidebranching is found to result either from noise amplification or from deterministic oscillations that exist both in two dimensions and in a three-dimensional thin-sample geometry. The oscillatory branch of growth solutions bifurcates subcritically from the main steady-state branch of solutions and exists over a finite range of large array spacings. In contrast, noise-induced sidebranching is associated with a smooth transition where the sidebranching amplitude increases exponentially with spacing up to nonlinear saturation due to the overlap of diffusion fields from neighboring cells, as observed experimentally. In the latter case where sidebranching is noise-induced, we find that increasing the externally imposed thermal gradient reduces the onset velocity and wavelength of sidebranching, as also observed experimentally. We show that this counterintuitive effect is due to tip blunting with increasing thermal gradient that promotes noise amplification in the tip region.

  8. Phase-field approach for faceted solidification

    Science.gov (United States)

    Debierre, Jean-Marc; Karma, Alain; Celestini, Franck; Guérin, Rahma

    2003-10-01

    We extend the phase-field approach to model the solidification of faceted materials. Our approach consists of using an approximate γ plot with rounded cusps that can approach arbitrarily closely the true γ plot with sharp cusps that correspond to faceted orientations. The phase-field equations are solved in the thin-interface limit with local equilibrium at the solid-liquid interface [A. Karma and W.-J. Rappel, Phys. Rev. E 53, R3017 (1996)]. The convergence of our approach is first demonstrated for equilibrium shapes. The growth of faceted needle crystals in an undercooled melt is then studied as a function of undercooling and the cusp amplitude δ for a γ plot of the form γ=γ0[1+δ(|sin θ|+|cos θ|)]. The phase-field results are consistent with the scaling law Λ˜V-1/2 observed experimentally, where Λ is the facet length and V is the growth rate. In addition, the variation of V and Λ with δ is found to be reasonably well predicted by an approximate sharp-interface analytical theory that includes capillary effects and assumes circular and parabolic forms for the front and trailing rough parts of the needle crystal, respectively.

  9. Stability of eutectic interface during directional solidification

    Energy Technology Data Exchange (ETDEWEB)

    Han, Seung Hoon [Iowa State Univ., Ames, IA (United States)

    1996-04-23

    Directional solidification of eutectic alloys shows different types of eutectic morphologies. These include lamellar, rod, oscillating and tilting modes. The growth of these morphologies occurs with a macroscopically planar interface. However, under certain conditions, the planar eutectic front becomes unstable and gives rise to a cellular or a dendritic structure. This instability leads to the cellular/dendritic structure of either a primary phase or a two-phase structure. The objective of this work is to develop a fundamental understanding of the instability of eutectic structure into cellular/dendritic structures of a single phase and of two-phases. Experimental studies have been carried out to examine the transition from a planar to two-phase cellular and dendritic structures in a ceramic system of Alumina-Zirconia (Al2O3-ZrO2) and in a transparent organic system of carbon tetrabromide and hexachloroethane (CBr4-C2Cl6). Several aspects of eutectic interface stability have been examined.

  10. SOLIDIFICATION TESTING FOR A HIGH ACTIVITY WASTESTREAM FROM THE SAVANNAH RIVER SITE USING GROUT AND GAMMA RADIATION SHEILDING MATERIALS - 10017

    Energy Technology Data Exchange (ETDEWEB)

    Burns, H.

    2009-11-10

    The U.S. Department of Energy (DOE) tasked MSE Technology Applications, Inc. (MSE) with evaluating grouts that include gamma radiation shielding materials to solidify surrogates of liquid aqueous radioactive wastes from across the DOE Complex. The Savannah River Site (SRS) identified a High Activity Waste (HAW) that will be treated and solidified at the Waste Solidification Building (WSB) for surrogate grout testing. The HAW, which is produced at the Mixed Oxide Fuel Fabrication Facility (MFFF), is an acidic aqueous wastestream generated by the alkaline treatment process and the aqueous purification process. The HAW surrogate was solidified using Portland cement with and without the inclusion of different gamma radiation shielding materials to determine the shielding material that is the most effective to attenuate gamma radiation for this application.

  11. Processing of alnico permanent magnets by advanced directional solidification methods

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Min; Johnson, Francis; Zhang, Wanming; Zhao, Qi; Rutkowski, Stephen F. [Ceramic and Metallurgy Technologies, General Electric Global Research, Niskayuna, NY (United States); Zhou, Lin; Kramer, Matthew J. [Ames Laboratory, Ames, IA (United States); Iowa State University, Ames, IA (United States)

    2016-12-15

    Advanced directional solidification methods have been used to produce large (>15 cm length) castings of Alnico permanent magnets with highly oriented columnar microstructures. In combination with subsequent thermomagnetic and draw thermal treatment, this method was used to enable the high coercivity, high-Titanium Alnico composition of 39% Co, 29.5% Fe, 14% Ni, 7.5% Ti, 7% Al, 3% Cu (wt%) to have an intrinsic coercivity (H{sub ci}) of 2.0 kOe, a remanence (B{sub r}) of 10.2 kG, and an energy product (BH){sub max} of 10.9 MGOe. These properties compare favorably to typical properties for the commercial Alnico 9. Directional solidification of higher Ti compositions yielded anisotropic columnar grained microstructures if high heat extraction rates through the mold surface of at least 200 kW/m{sup 2} were attained. This was achieved through the use of a thin walled (5 mm thick) high thermal conductivity SiC shell mold extracted from a molten Sn bath at a withdrawal rate of at least 200 mm/h. However, higher Ti compositions did not result in further increases in magnet performance. Images of the microstructures collected by scanning electron microscopy (SEM) reveal a majority α phase with inclusions of secondary α{sub γ} phase. Transmission electron microscopy (TEM) reveals that the α phase has a spinodally decomposed microstructure of FeCo-rich needles in a NiAl-rich matrix. In the 7.5% Ti composition the diameter distribution of the FeCo needles was bimodal with the majority having diameters of approximately 50 nm with a small fraction having diameters of approximately 10 nm. The needles formed a mosaic pattern and were elongated along one 〈001〉 crystal direction (parallel to the field used during magnetic annealing). Cu precipitates were observed between the needles. Regions of abnormal spinodal morphology appeared to correlate with secondary phase precipitates. The presence of these abnormalities did not prevent the material from displaying superior magnetic

  12. Processing of alnico permanent magnets by advanced directional solidification methods

    Science.gov (United States)

    Zou, Min; Johnson, Francis; Zhang, Wanming; Zhao, Qi; Rutkowski, Stephen F.; Zhou, Lin; Kramer, Matthew J.

    2016-12-01

    Advanced directional solidification methods have been used to produce large (>15 cm length) castings of Alnico permanent magnets with highly oriented columnar microstructures. In combination with subsequent thermomagnetic and draw thermal treatment, this method was used to enable the high coercivity, high-Titanium Alnico composition of 39% Co, 29.5% Fe, 14% Ni, 7.5% Ti, 7% Al, 3% Cu (wt%) to have an intrinsic coercivity (Hci) of 2.0 kOe, a remanence (Br) of 10.2 kG, and an energy product (BH)max of 10.9 MGOe. These properties compare favorably to typical properties for the commercial Alnico 9. Directional solidification of higher Ti compositions yielded anisotropic columnar grained microstructures if high heat extraction rates through the mold surface of at least 200 kW/m2 were attained. This was achieved through the use of a thin walled (5 mm thick) high thermal conductivity SiC shell mold extracted from a molten Sn bath at a withdrawal rate of at least 200 mm/h. However, higher Ti compositions did not result in further increases in magnet performance. Images of the microstructures collected by scanning electron microscopy (SEM) reveal a majority α phase with inclusions of secondary αγ phase. Transmission electron microscopy (TEM) reveals that the α phase has a spinodally decomposed microstructure of FeCo-rich needles in a NiAl-rich matrix. In the 7.5% Ti composition the diameter distribution of the FeCo needles was bimodal with the majority having diameters of approximately 50 nm with a small fraction having diameters of approximately 10 nm. The needles formed a mosaic pattern and were elongated along one crystal direction (parallel to the field used during magnetic annealing). Cu precipitates were observed between the needles. Regions of abnormal spinodal morphology appeared to correlate with secondary phase precipitates. The presence of these abnormalities did not prevent the material from displaying superior magnetic properties in the 7.5% Ti composition

  13. Effects of temperature and organic loading rate on the performance and microbial community of anaerobic co-digestion of waste activated sludge and food waste.

    Science.gov (United States)

    Gou, Chengliu; Yang, Zhaohui; Huang, Jing; Wang, Huiling; Xu, Haiyin; Wang, Like

    2014-06-01

    Anaerobic co-digestion of waste activated sludge and food waste was investigated semi-continuously using continuously stirred tank reactors. Results showed that the performance of co-digestion system was distinctly influenced by temperature and organic loading rate (OLR) in terms of gas production rate (GPR), methane yield, volatile solids (VS) removal efficiency and the system stability. The highest GPR at 55 °C was 1.6 and 1.3 times higher than that at 35 and 45 °C with the OLR of 1 g VSL(-1)d(-1), and the corresponding average CH₄ yields were 0.40, 0.26 and 0.30 L CH₄ g(-1)VSadded, respectively. The thermophilic system exhibited the best load bearing capacity at extremely high OLR of 7 g VSL(-1)d(-1), while the mesophilic system showed the best process stability at low OLRs (< 5 g VSL(-1)d(-1)). Temperature had a more remarkable effect on the richness and diversity of microbial populations than the OLR. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Weld solidification cracking in 304 to 304L stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Hochanadel, Patrick W [Los Alamos National Laboratory; Lienert, Thomas J [Los Alamos National Laboratory; Martinez, Jesse N [Los Alamos National Laboratory; Martinez, Raymond J [Los Alamos National Laboratory; Johnson, Matthew Q [Los Alamos National Laboratory

    2010-01-01

    A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for GTAW display a greater range of compositions that are not crack susceptible relative to those developed for pulsed LBW. Contrary to the predictions of the GTAW weldability diagram, cracking was found. This result was rationalized in terms of the more rapid solidification rate of the pulsed gas tungsten arc welds. In addition, for the pulsed LBW conditions, the material compositions were predicted to be, by themselves, 'weldable' according to the pulsed LBW weldability diagram. However, the composition range along the tie line connecting the two compositions passed through the crack susceptible range. Microstructurally, the primary solidification mode (PSM) of the material processed with higher power LBW was determined to be austenite (A), while solidification mode of the materials processed with lower power LBW apparently exhibited a dual PSM of both austenite (A) and ferrite-austenite (FA) within the same weld. The materials processed by pulsed GT A W showed mostly primary austenite solidification, with some regions of either primary austenite-second phase ferrite (AF) solidification or primary ferrite-second phase austenite (FA) solidification. This work demonstrates that variations in crack susceptibility may be realized when welding different heats of 'weldable' materials together, and that slight variations in processing can also contribute to crack susceptibility.

  15. Weld solidification cracking in 304 to 204L stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Hochanadel, Patrick W [Los Alamos National Laboratory; Lienert, Thomas J [Los Alamos National Laboratory; Martinez, Jesse N [Los Alamos National Laboratory; Johnson, Matthew Q [Los Alamos National Laboratory

    2010-09-15

    A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for GTAW display a greater range of compositions that are not crack susceptible relative to those developed for pulsed LBW. Contrary to the predictions of the GTAW weldability diagram, cracking was found.This result was rationalized in terms of the more rapid solidification rate of the pulsed gas tungsten arc welds. In addition, for the pulsed LBW conditions, the material compositions were predicted to be, by themselves, 'weldable' according to the pulsed LBW weldability diagram. However, the composition range along the tie line connecting the two compositions passed through the crack susceptible range. Microstructurally, the primary solidification mode (PSM) of the material processed with higher power LBW was determined to be austenite (A), while solidification mode of the materials processed with lower power LBW apparently exhibited a dual PSM of both austenite (A) and ferrite-austenite (FA) within the same weld. The materials processed by pulsed GTAW showed mostly primary austenite solidification, with some regions of either primary austenite-second phase ferrite (AF) solidification or primary ferrite-second phase austenite (FA) solidification. This work demonstrates that variations in crack susceptibility may be realized when welding different heats of 'weldable' materials together, and that slight variations in processing can also contribute to crack susceptibility.

  16. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Volume 3, Model parameters: Sandia WIPP Project

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-29

    This volume documents model parameters chosen as of July 1992 that were used by the Performance Assessment Department of Sandia National Laboratories in its 1992 preliminary performance assessment of the Waste Isolation Pilot Plant (WIPP). Ranges and distributions for about 300 modeling parameters in the current secondary data base are presented in tables for the geologic and engineered barriers, global materials (e.g., fluid properties), and agents that act upon the WIPP disposal system such as climate variability and human-intrusion boreholes. The 49 parameters sampled in the 1992 Preliminary Performance Assessment are given special emphasis with tables and graphics that provide insight and sources of data for each parameter.

  17. Energy recovery from Municipal Solid Waste in EU: proposals to assess the management performance under a circular economy perspective

    Directory of Open Access Journals (Sweden)

    Rada Elena Cristina

    2017-01-01

    Full Text Available In 2015 the European Commission issued a package of documents on Circular Economy concerning an integrated revision of legislative proposals on waste management. The aim was to stimulate a European transition towards a circular economy concept, which is expected to foster competitiveness, sustainable economic growth and new jobs generation. Three indicators are proposed in this paper to contribute to the assessment of the energy recovery management performance from MSW in a scenario of circular economy: a referring to MSW directly used (RMSW or indirectly used (SRF as input of thermochemical plants, an indicator can be the percentage of waste having LHV > 13MJ/kg; b referring to the MSW directly or indirectly used as input of thermochemical plants, the percentage of waste having ash recovered; c referring to food waste, percentage of this stream sent to anaerobic digestion. The above indicators, proposed and discussed in this paper, have to be integrated with other ones in order to complete the quantification of the role of MSW management in term of energy recovery under a circular economy strategy. It is not the aim of the present paper to give a comprehensive solution to this complex issue.

  18. Supplementation of Morinda citrifolia waste as bioactive compound on the performances of broiler

    Directory of Open Access Journals (Sweden)

    I.A.K Bintang

    2007-03-01

    Full Text Available A study on the use of dried Morinda citrifolia waste as feed additive in broiler ration was conducted. One hundred day old chicks (doc were allocated into 4 levels (control; 0.0; 1.2; 2.4 and 4.8 g/kg feed of M. citrifolia waste with 5 replication. Each replication had 5 birds. The treatments were allocated in a completely randomized design. Variables measured were: feed intake, live weight, feed conversion ratio (FCR, percentages of carcass and internal organs ( liver. gizard, abdominal fat, and thickness of intestine. The results showed that M citrifolia waste supply did not significantly (P>0.05 affect all variables measured, but feed intake of those fed with high levels (4,8 g/kg of M. citrifolia waste was significantly (P<0.05 lower than those fed with 1.2 g/kg. FCR was significantly (P<0.05 lower as compared to the control; 1.2 and 2.4 g/kg. It is concluded that the best treatment was the supplementation of M. citrifolia waste of 4.8 g/kg, this treatment improved feed efficiency by 5% as compared to the control.

  19. Performance evaluation of integrated solid-liquid wastes treatment technology in palm oil industry

    Science.gov (United States)

    Amelia, J. R.; Suprihatin, S.; Indrasti, N. S.; Hasanudin, U.; Fujie, K.

    2017-05-01

    The oil palm industry significantly contributes to environmental degradation if without waste management properly. The newest alternative waste management that might be developed is by utilizing the effluent of POME anaerobic digestion with EFB through integrated anaerobic decomposition process. The aim of this research was to examine and evaluate the integrated solid-liquid waste treatment technology in the view point of greenhouse gasses emission, compost, and biogas production. POME was treated in anaerobic digester with loading rate about 1.65 gCOD/L/day. Treated POME with dosis of 15 and 20 L/day was sprayed to the anaerobic digester that was filled of 25 kg of EFB. The results of research showed that after 60 days, the C/N ratio of EFB decreased to 12.67 and 10.96 for dosis of treated POME 15 and 20 L/day, respectively. In case of 60 day decomposition, the integrated waste treatment technology could produce 51.01 and 34.34 m3/Ton FFB which was equivalent with 636,44 and 466,58 kgCO2e/ton FFB for dosis of treated POME 15 and 20 L/day, respectively. The results of research also showed that integrated solid-liquid wastes treatment technology could reduce GHG emission about 421.20 and 251.34 kgCO2e/ton FFB for dosis of treated POME 15 and 20 L/day, respectively.

  20. Mechanical and Physical Performance of Concrete Including Waste Electrical Cable Rubber

    Science.gov (United States)

    Taner Yildirim, Salih; Pelin Duygun, Nur

    2017-10-01

    Solid wastes are important environmental problem all over the World. Consumption of the plastic solid waste covers big portion within the total solid waste. Although a numerous plastic material is subjected to the recycling process, it is not easy to be destroyed by nature. One of the recommended way to prevent is to utilize as an aggregate in cement-based material. There are many researches on use of recycling rubber in concrete. However, studies on recycling of waste electrical cable rubber (WECR) in concrete is insufficient although there are many research on waste tyre rubbers in concrete. In this study, fine aggregate was replaced with WECR which were 5%, 10%, and 15 % of the total aggregate volume in the concrete and researched workability, unit weight, water absorption, compressive strength, flexural strength, ultrasonic pulse velocity, modulus of elasticity, and abrasion resistance of concrete. As a result of experimental studies, increase of WECR amount in concrete increases workability due to lack of adherence between cement paste and WECR, and hydrophobic structure of WECR while it influences negatively mechanical properties of concrete. It is possible to use WECR in concrete taking into account the reduction in mechanical properties.

  1. Evaluation of Materials Performance in a Large-Scale Glass Melter after Two Years of Vitrifying Simulated SRP Defense Waste

    Energy Technology Data Exchange (ETDEWEB)

    Iverson, D.C.

    1984-11-21

    The Large Slurry Fed Melter (LSFM) at the Department of Energy's Savannah River Plant recently completed two years of service and was shut down for evaluation. This paper reviews the melter operating history and describes the condition of the refractories and metal components. The excellent condition of the LSFM verifies the expected performance of the materials of construction and indicates that a two year melter life is achievable in the Defense Waste Processing Facility (DWPF).

  2. Preparation of activated carbon from molasses-to-ethanol process waste vinasse and its performance as adsorbent material.

    Science.gov (United States)

    Kazak, Omer; Ramazan Eker, Yasin; Bingol, Haluk; Tor, Ali

    2017-10-01

    Herein, the preparation of activated carbon from waste vinasse by using hydrothermal H 2 O 2 oxidation combined with a two-step pyrolysis process has been described for the first time as a new utilization approach for the waste vinasse. The characterization studies were performed by TGA, FT-IR, Raman spectroscopy, SEM-EDX and gas adsorption measurements. The approach generated a microporous activated carbon with high specific surface area (989m 2 /g) from waste vinasse. After simple experiments on various dye solutions, adsorption performance of the activated carbon was specifically studied on the methylene blue solution as functions of solution pH, contact time, adsorbent amount and reusability. The obtained activated carbon had a higher Langmuir adsorption capacity towards methylene blue (909.091±31.900mg/g) than many other adsorbents and it is reusable for at least six cycles. The adsorption performance of the obtained activated carbon was also evaluated using both simulated and real dye-house effluents. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Performance and kinetic study of semi-dry thermophilic anaerobic digestion of organic fraction of municipal solid waste.

    Science.gov (United States)

    Sajeena Beevi, B; Madhu, G; Sahoo, Deepak Kumar

    2015-02-01

    Anaerobic digestion (AD) of the organic fraction of municipal solid waste (OFMSW) is promoted as an energy source and waste disposal. In this study semi dry anaerobic digestion of organic solid wastes was conducted for 45 days in a lab-scale batch experiment for total solid concentration of 100g/L for investigating the start-up performances under thermophilic condition (50 °C). The performance of the reactor was evaluated by measuring the daily biogas production and calculating the degradation of total solids and the total volatile solids. The biogas yield at the end of the digestion was 52.9L/kg VS (volatile solid) for the total solid (TS) concentration of 100g/L. About 66.7% of the volatile solid degradation was obtained during the digestion. A first order model based on the availability of substrate as the limiting factor was used to perform the kinetic studies of batch anaerobic digestion system. The value of reaction rate constant, k, obtained was 0.0249 day(-1). Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Effects of Partition Coefficients, Diffusion Coefficients, and Solidification Paths on Microsegregation in Fe-Based Multinary Alloy

    Science.gov (United States)

    Huang, Yunwei; Long, Mujun; Liu, Peng; Chen, Dengfu; Chen, Huabiao; Gui, Lintao; Liu, Tao; Yu, Sheng

    2017-10-01

    To quantitatively study the effects of partition coefficients, diffusion coefficients, and solidification paths on solute microsegregation, an analytical model was developed combined with the calculation of thermodynamic software FactSage. This model, applied with variational partition coefficients and temperature-dependent diffusion coefficients, is based on the Voller-Beckermann model and is extended to take into account the effects of multiple components and the peritectic phase transformation using FactSage. The predictions agree well with a range of measured data and the results of other numerical solutions. As the results indicate, the partition coefficients of solutes are functions of temperature and phase fraction during the solidification process, and the solute microsegregation increases significantly with decreasing partition coefficients. The calculations of solute microsegregation ratio ( C L/ C 0) in the interdendritic region are related to solidification paths. The microsegregation ratios of P and S increase as the initial C concentration increases, while they reduce with increasing initial C contents for solutes C and Si. Parameter sensitivity analysis was performed, and the results indicate that the solute microsegregation shows larger variation with partition coefficients and solidification paths than diffusion coefficients.

  5. A phenomenological approach of solidification of polymeric phase change materials

    Science.gov (United States)

    Bahrani, Seyed Amir; Royon, Laurent; Abou, Bérengère; Osipian, Rémy; Azzouz, Kamel; Bontemps, André

    2017-01-01

    Phase Change Materials (PCMs) are widely used in thermal energy storage and thermal management systems due to their small volume for a given stored energy and their capability for maintaining nearly constant temperatures. However, their performance is limited by their low thermal conductivity and possible leaks while in the liquid phase. One solution is to imprison the PCM inside a polymer mesh to create a Polymeric Phase Change Material (PPCM). In this work, we have studied the cooling and solidification of five PPCMs with different PCMs and polymer fractions. To understand the heat transfer mechanisms involved, we have carried out micro- and macrorheological measurements in which Brownian motion of tracers embedded in PPCMs has been depicted and viscoelastic moduli have been measured, respectively. Beyond a given polymer concentration, it was shown that the Brownian motion of the tracers is limited by the polymeric chains and that the material exhibits an elastic behavior. This would suggest that heat transfer essentially occurs by conduction, instead of convection. Experiments were conducted to measure temperature variation during cooling of the five samples, and a semi-empirical model based on a phenomenological approach was proposed as a practical tool to choose and size PPCMs.

  6. Field lysimeter studies for performance evaluation of grouted Hanford defense wastes

    Energy Technology Data Exchange (ETDEWEB)

    Last, G.V.; Serne, R.J.; LeGore, V.L.

    1995-02-01

    The Grout Waste Test Facility (GWTF) consisted of four large field lysimeters designed to test the leaching and migration rates of grout-solidified low-level radioactive wastes generated by Hanford Site operations. Each lysimeter was an 8-m-deep by 2-media closed-bottom caisson that was placed in the ground such that the uppermost rim remained just above grade. Two of these lysimeters were used; the other two remained empty. The two lysimeters that were used (A-1 and B-1) were backfilled with a two-layer soil profile representative of the proposed grout disposal site. The proposed grout disposal site (termed the Grout Treatment Facility Landfill) is located immediately east of the Hanford Site`s 200 East Area. This soil profile consisted of a coarse sand into which the grout waste forms were placed and covered by 4 m of a very fine sand. The A-1 lysimeter was backfilled in March 1985, with a grout-solidified phosphate/sulfate liquid waste from N Reactor decontamination and ion exchange resin regeneration. The B-1 lysimeter was backfilled in September 1985 and received a grout-solidified simulated cladding removal waste representative of waste generated from fuel reprocessing operations at the head end of the Plutonium Uranium Extraction (PUREX) plant. Routine monitoring and leachate collection activities were conducted for over three years, terminating in January 1989. Drainage was collected sporadically between January 1989 and December 1992. Decontamination and decommissioning of these lysimeters during the summer of 1994, confirmed the presence of a 15 to 20-cm-long hairline crack in one of the bottom plate welds. This report discusses the design and construction of the GWTF, presents the routine data collected from this facility through January 1989 and subsequent data collected sporadically between 1989 and 1993, and provides a brief discussion concerning preliminary interpretation of the results.

  7. Performance characterization of water recovery and water quality from chemical/organic waste products

    Science.gov (United States)

    Moses, W. M.; Rogers, T. D.; Chowdhury, H.; Cullingford, H. S.

    1989-01-01

    The water reclamation subsystems currently being evaluated for the Space Shuttle Freedom are briefly reviewed with emphasis on a waste water management system capable of processing wastes containing high concentrations of organic/inorganic materials. The process combines low temperature/pressure to vaporize water with high temperature catalytic oxidation to decompose volatile organics. The reclaimed water is of potable quality and has high potential for maintenance under sterile conditions. Results from preliminary experiments and modifications in process and equipment required to control reliability and repeatability of system operation are presented.

  8. Predicting weld solidification cracking using damage mechanics -- LDRD summary report

    Energy Technology Data Exchange (ETDEWEB)

    Dike, J.J.; Brooks, J.A.; Bammann, D.J.; Li, M.; Krafcik, J.S.; Yang, N.Y.C.

    1997-04-01

    This report summarizes the efforts to develop and validate a finite element based model to predict weld solidification cracking behavior. Such a model must capture the solidification behavior, the thermal behavior in the weld pool region, the material mechanical response, and some failure criteria to determine when solidification cracking will occur. For such a program to be successful, each aspect of the model had to be accurately modeled and verified since the output of one portion of the model served as the input to other portions of the model. A solidification model which includes dendrite tip and eutectic undercooling was developed and used in both the thermal and mechanical finite element analysis. High magnification video techniques were developed to measure strains for validation of the mechanical predictions using a strain rate and temperature dependent constitutive model. This model was coupled with a ductile void growth damage model and correlated with experimental observations to determine capabilities of predicting cracking response. A two phase (solid + liquid) material model was also developed that can be used to more accurately capture the mechanics of weld solidification cracking. In general, reasonable agreement was obtained between simulation and experiment for location of crack initiation and extent of cracking for 6061-T6 aluminum. 35 refs.

  9. Directional solidification studies in Ni-Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Je-hyun [Iowa State Univ., Ames, IA (United States)

    1993-05-01

    Three solid phases are involved in the phase equilibria of the intermetallic compound Ni3Al near its melting point, β, γ'(Ni3Al), and γ. The generally-accepted phase diagram involves a eutectic reaction between β' and γ, but some recent studies agree with an older diagram due to Schramm, which has a eutectic reaction between the β and γ' phases. The phase equilibria near Ni3Al compositions was evaluated using quenched directional solidification experiments, that preserve the microstructures tonned at the solidification front, and using diffusion couple experiments. These experiments show that eutectic forms between β and γ' phases, as in the Schramm diagram. Growth and phase transformations of these three phases are also studied in the directional solidification experiments. Microstructure analysis shows that etching of Ni3Al(γ') is very sensitive to small composition variations and crystallographic orientation changes. The eutectic solidification study confirms that the equilibrium eutectic is γ'+β, and that the metastable γ+β eutectic might be also produced in this system according to the impurities, solidification rates, and composition variations.

  10. Solidification and stabilization of the incinerated wastewater sludge from textile industry

    Science.gov (United States)

    Aziz, Hamidi Abdul; Ghazali, Miskiah Fadzilah; Omran, Abdelnaser; Umar, Muhammad

    2017-10-01

    This paper describes the investigation of solidification and stabilization (S/S) process for the safe disposal of incinerated wastewater sludge produced from a textile industry in Penang, Malaysia. Physical and chemical properties of the samples were first characterized. Various ratios of ordinary Portland cement (OPC) as a binder were used to immobilize the metals. The leachability of metals in these cement-based waste materials was studied by standard toxicity characteristic leaching procedure (TCLP) and the mechanical strength was tested by a compressive strength test. TCLP results showed the ability of OPC to immobilize various metals such as Zn, Cu, Fe, Al, Ti, and K within the limits set by USEPA and Malaysia Environment Quality Act, 1974. However, the strength of the solidified matrixes was generally lower than the control specimens, ranging from 1-23 Mpa, which was well above the specified limit of 414 kPa for such matrices for their disposal in landfills.

  11. Continuous solidification of photovoltaic multicrystalline silicon from an inductive cold crucible

    Energy Technology Data Exchange (ETDEWEB)

    Dour, Gilles [Ecole des Mines, Albi-Carmaux (France); Ehret, Eric; Laugier, A. [LPM INSA, Lyon (France); Sarti, Dominique [Photowatt Int., Bourgoin-Jallieu (France); Garnier, Marcel; Durand, Francis [EPM-Madylam, CNRS and INP Grenoble, ENSHMG, BP 95, F-38402 St. Martin d`Heres (France)

    1998-09-15

    An inductive cold crucible is used to melt photovoltaic granular silicon and to form massive multicrystalline billets by continuous pulling downwards. The cold crucible is noncontaminating. In the billet the impurity content is kept at the same low level as it is in the feed stock, even for copper, and somewhat lower for oxygen. Square billets are as easy to shape as circular ones. Continuous solidification gives the material uniform grain structure and properties, so that a considerable reduction in waste material is expected. Details are given on the experimental procedure and on measurements. For a given pulling rate, the optimal electrical conditions result from a fine compromise between the risk of a liquid leak, and the risk of nonmelting granules. Among the electrical and thermal measurements which were tested, the electrical frequency seems to give a possible gage for estimating the variation of the amount of liquid

  12. Refining of metallurgical silicon by directional solidification

    Energy Technology Data Exchange (ETDEWEB)

    Martorano, M.A., E-mail: martoran@usp.br [Department of Metallurgical and Materials Engineering, University of Sao Paulo, Av. Prof. Mello Moraes, 2463 Sao Paulo-SP, 05508-900 (Brazil); Neto, J.B. Ferreira, E-mail: jbfn@ipt.br [Laboratory of Metallurgy and Ceramics Materials, Institute for Technological Research, Av. Prof. Almeida Prado, 532, Sao Paulo-SP, 05508-901 (Brazil); Oliveira, T.S., E-mail: theo.usp@bol.com.br [Department of Metallurgical and Materials Engineering, University of Sao Paulo, Av. Prof. Mello Moraes, 2463 Sao Paulo-SP, 05508-900 (Brazil); Tsubaki, T.O., E-mail: tomoe@ipt.br [Laboratory of Metallurgy and Ceramics Materials, Institute for Technological Research, Av. Prof. Almeida Prado, 532, Sao Paulo-SP, 05508-901 (Brazil)

    2011-02-25

    The directional solidification of a typical and a previously refined metallurgical silicon was carried out in a vertical Bridgman furnace. The mold velocity out of the hot zone of the furnace changed from one experiment to another in the range between 5 and 110 {mu}m s{sup -1}. Samples were extracted from the cylindrical ingots obtained in the experiments to investigate the effects of the mold velocity on the micro and macrostructures and on the concentration profiles of impurities along the ingots. At the lowest mold velocity, the macrostructures consist of columnar grains oriented approximately parallel to the ingot axis. As velocity increases, grains become thinner and more inclined in the radial direction. Precipitated particles containing Si, Fe, Al, and Ti are observed at the top of all ingots and, as the mold velocity increases, they are also seen at the ingot bottom and middle. The concentration profiles of several impurities have been measured along the ingots by inductively coupled plasma atomic emission spectrometry (ICP), indicating an accumulation of impurities at the ingot top. Consequently, the bottom and middle of the ingots are purer than the corresponding metallurgical silicon from which they solidified. Slices from the ingot bottom have also been analyzed by the glow discharge mass spectrometry technique (GDMS), allowing measurement of impurity concentrations that were below the quantification limit of the ICP. The purification effect and the accumulation of impurities at the ingot top are more pronounced as the mold velocity decreases. In the ingots obtained from the typical metallurgical silicon at the lowest mold velocities (5 and 10 {mu}m s{sup -1}), except for Al, all impurities are in concentrations below an important maximum limit for the feedstock of solar grade silicon. At the same mold velocities, the concentrations of Fe, Ti, Cu, Mn, and Ni measured at the bottom of the ingots obtained from both types of metallurgical silicon (typical

  13. Influence of Kitchen/food waste on growth performance of grower piglets

    Directory of Open Access Journals (Sweden)

    Saikia

    2010-02-01

    Full Text Available Crossbred (Landrace x Desi pigs (24 were randomly distributed into 2 dietary treatments (T1 and T2 diets each having 12 pigs of 6 castrated male and 6 females. The pigs were fed on ad libitum control diet in T1 and ad libitum FW in T2 collected from student’s hostel and air force mess. During the feeding trial, the CP and EE %of food wastes was found to be higher in food waste (FW than standard ration (SR. However, CF was less in FW. The DMI (g/d was significantly lower in pigs fed on food waste based diets. However, ADG was significantly (P<0.05 higher in T2, which in turn increasing feed conversion efficiency of pigs in T2. Feed cost per kg live weight gain was also lower (P<0.05 in T2 compared to T1. Thus, it can be concluded that nutritive value of food waste based diets was much higher than the concentrate mixture based diets. Piglets grew more in FW based diets and could be utilized as an alternate economic feed for pigs without any negative effects. [Vet. World 2010; 3(1.000: 34-36

  14. Process performance and modelling of anaerobic digestion using source-sorted organic household waste

    DEFF Research Database (Denmark)

    Khoshnevisan, Benyamin; Tsapekos, Panagiotis; Alvarado-Morales, Merlin

    2018-01-01

    Three distinctive start-up strategies of biogas reactors fed with source-sorted organic fraction of municipal solid waste were investigated to reveal the most reliable procedure for rapid process stabilization. Moreover, the experimental results were compared with mathematical modeling outputs. T...

  15. Agglomeration behaviour of steel plants solid waste and its effect on sintering performance

    Directory of Open Access Journals (Sweden)

    Prince Kumar Singh

    2017-07-01

    Full Text Available Recycling has been the fascinating topic among the researchers for all times. The present study shows the recycling of steel plant's solid wastes as blast furnace flue dust and sludge towards agglomeration and their use in the production of sinter. These wastes consist of metal oxides and coke fines as a valuable material with some alkali oxides. Using these wastes as it is in the form of fines exacerbate the further processing. Pellets of these wastes are prepared with three types of binders as molasses, dextrin and bentonite. The result reveals that properties as compressive strength, shatter strength, are better in the case of bentonite binder having the productivity of the disc pelletizer machine as 75. After that, these macro pellets used for sintering with iron ore and other ingredients in pot type, down draft laboratory grade sintering machine, which shows very high productivity and good mechanical properties of the sinter as well. The microstructural analysis reveals the presence of re-oxidized hematite and a little bit of a magnetite phase with some slag phases, which confirmed later by XRD analysis. Results also show the decrease in coke rate, i.e. coke consumption to produce sinter and at the same time, this process is highly eco-friendly.

  16. Improved Economic Performance of Municipal Solid Waste Combustion Plants by Model Based Combustion Control

    NARCIS (Netherlands)

    Leskens, M.

    2013-01-01

    The combustion of municipal solid waste (MSW) is used for its inertisation, reduction of its volume and the conversion of its energy content into heat and/or electricity. Operation and control of modern large scale MSW combustion (MSWC) plants is determined by economic and environmental objectives

  17. Solidification of arsenic and heavy metal containing tailings using cement and blast furnace slag.

    Science.gov (United States)

    Kim, Jung-Wook; Jung, Myung Chae

    2011-01-01

    The objective of this study is to examine the solidification of toxic elements in tailings by the use of cement and blast furnace slag. Tailings samples were taken at an Au-Ag mine in Korea. To examine the best mixing ratio of tailings and the mixture of ordinary Portland cement (OPC) and blast furnace slag (SG) of 5:5, 6:6, 7:3, and 8:2, the 7:3 ratio of tailings and OPC+SG was adapted. In addition, the mixing ratios of water and OPC + SG were applied to 10, 20, and 30 wt%. After 7, 14, and 28 days' curing, the UCS test was undertaken. A relatively high strength of solidified material (137.2 kg cm⁻² in average of 3 samples) at 28 days' curing was found in 20 wt% of water content (WC). This study also examined the leachability of arsenic and heavy metals (Cd, Cu, Pb, and Zn) under the Korean Standard Leaching Test, and it showed that the reductions in leachabilities of As and heavy metals of solidified samples were ranged from 76 to 99%. Thus, all the solidified samples were within the guidelines for special and hazardous waste materials by the Waste Management Act in Korea. In addition, the result of freeze-thaw cycle test of the materials indicated that the durability of the materials was sufficient. In conclusion, solidification using a 7:3 mixing ratio of tailings and a 1:1 mixture of OPC + SG with 20% of WC is one of the best methods for the remediation of arsenic and heavy metals in tailings and other contaminated materials.

  18. A mathematical model for the performance assessment of engineering barriers of a typical near surface radioactive waste disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, Raphaela N.; Rotunno Filho, Otto C. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Lab. de Hidrologia e Estudos do Meio Ambiente]. E-mail: otto@hidro.ufrj.br; Ruperti Junior, Nerbe J.; Lavalle Filho, Paulo F. Heilbron [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)]. E-mail: nruperti@cnen.gov.br

    2005-07-01

    This work proposes a mathematical model for the performance assessment of a typical radioactive waste disposal facility based on the consideration of a multiple barrier concept. The Generalized Integral Transform Technique is employed to solve the Advection-Dispersion mass transfer equation under the assumption of saturated one-dimensional flow, to obtain solute concentrations at given times and locations within the medium. A test-case is chosen in order to illustrate the performance assessment of several configurations of a multi barrier system adopted for the containment of sand contaminated with Ra-226 within a trench. (author)

  19. Use of groundwater lifetime expectancy for the performance assessment of a deep geologic waste repository: 1. Theory, illustrations, and implications

    CERN Document Server

    Cornaton, F J; Normani, S D; Sudicky, E A; Sykes, J F

    2011-01-01

    Long-term solutions for the disposal of toxic wastes usually involve isolation of the wastes in a deep subsurface geologic environment. In the case of spent nuclear fuel, if radionuclide leakage occurs from the engineered barrier, the geological medium represents the ultimate barrier that is relied upon to ensure safety. Consequently, an evaluation of radionuclide travel times from a repository to the biosphere is critically important in a performance assessment analysis. In this study, we develop a travel time framework based on the concept of groundwater lifetime expectancy as a safety indicator. Lifetime expectancy characterizes the time that radionuclides will spend in the subsurface after their release from the repository and prior to discharging into the biosphere. The probability density function of lifetime expectancy is computed throughout the host rock by solving the backward-in-time solute transport adjoint equation subject to a properly posed set of boundary conditions. It can then be used to defi...

  20. LIFE ESTIMATION OF HIGH LEVEL WASTE TANK STEEL FOR F-TANK FARM CLOSURE PERFORMANCE ASSESSMENT - 9310

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, K; Bruce Wiersma, B; Stephen Harris, S

    2009-01-12

    High level radioactive waste (HLW) is stored in underground carbon steel storage tanks at the Savannah River Site. The underground tanks will be closed by removing the bulk of the waste, chemical cleaning, heel removal, stabilizing remaining residuals with tailored grout formulations, and severing/sealing external penetrations. The life of the carbon steel materials of construction in support of the performance assessment has been completed. The estimation considered general and localized corrosion mechanisms of the tank steel exposed to grouted conditions. A stochastic approach was followed to estimate the distributions of failures based upon mechanisms of corrosion accounting for variances in each of the independent variables. The methodology and results used for one-type of tank is presented.