Studies on sludge from storage tank of waxy crude oil. Part I: structure and composition of distillate fractions

Energy Technology Data Exchange (ETDEWEB)

Fazal, S.A.; Zarapkar, S.S.; Joshi, G.C. [D.G. Ruparel College, Bombay (India). Dept. of Chemistry

1995-08-01

Tank bottom sludge from storage tanks of Bombay High crude oil deposited during ten years have been studied. The yield of the sludge is approximately 0.1% wt. of the crude oil through-put. The residue boiling above 500{degree}C amounts to over 50%. The distillate fractions collected at 50{degree}C intervals have been analyzed extensively and compared to fractions from whole crude of same boiling range. The sludge distillate are distinctly more paraffinic in nature. 15 refs., 7 tabs.

EXPECTED IMPACT OF HANFORD PROCESSING ORGANICS OF PLUTONIUM DURING TANK WASTE SLUDGE RETRIEVAL

International Nuclear Information System (INIS)

TROYER, G.L.; WINTERS, W.I.

2004-01-01

This document evaluates the potential for extracting plutonium from Hanford waste tanks into residual organic solvents and how this process may have an impact on criticality specifications during the retrieval of wastes. The two controlling factors for concentrating plutonium are the solubility of the plutonium in the wastes and the extraction efficiency of the potential organic extractants that may be found in these wastes. Residual Hanford tank sludges contain plutonium in solid forms that are expected to be primarily insoluble Pu(IV) hydroxides. Evaluation of thermodynamic Pourbaix diagrams, documentation on solubility studies of various components in waste tank matrices, and actual analysis of plutonium in tank supernates all indicate that the solubility of Pu in the alkaline waste is on the order of 10 -6 M. Based on an upper limit plutonium solubility of 10 -5 M in high pH and a conservative distribution coefficient for organic extractants of a 0 for plutonium in 30% TBP at 0.07 M HNO 3 ), the estimated concentration for plutonium in the organic phase would be -7 M. This is well below the process control criteria. A significant increase in plutonium solubility or the E a o would have to occur to raise this concentration to the 0.01 M concern level for organics. Measured tank chemical component values, expected operating conditions, and the characteristics of the expected chemistry and extraction mechanisms indicate that concentration of plutonium from Hanford tank residual sludges to associated process organic extractants is significantly below levels of concern

POTENTIAL IMPACT OF BLENDING RESIDUAL SOLIDS FROM TANKS 18/19 MOUNDS WITH TANK 7 OPERATIONS

Energy Technology Data Exchange (ETDEWEB)

Eibling, R; Erich Hansen, E; Bradley Pickenheim, B

2007-03-29

High level waste tanks 18F and 19F have residual mounds of waste which may require removal before the tanks can be closed. Conventional slurry pump technology, previously used for waste removal and tank cleaning, has been incapable of removing theses mounds from tanks 18F and 19F. A mechanical cleaning method has been identified that is potentially capable of removing and transferring the mound material to tank 7F for incorporation in a sludge batch for eventual disposal in high level waste glass by the Defense Waste Processing Facility. The Savannah River National Laboratory has been requested to evaluate whether the material transferred from tanks 18F/19F by the mechanical cleaning technology can later be suspended in Tank 7F by conventional slurry pumps after mixing with high level waste sludge. The proposed mechanical cleaning process for removing the waste mounds from tanks 18 and 19 may utilize a high pressure water jet-eductor that creates a vacuum to mobilize solids. The high pressure jet is also used to transport the suspended solids. The jet-eductor system will be mounted on a mechanical crawler for movement around the bottom of tanks 18 and 19. Based on physical chemical property testing of the jet-eductor system processed IE-95 zeolite and size-reduced IE-95 zeolite, the following conclusions were made: (1) The jet-eductor system processed zeolite has a mean and median particle size (volume basis) of 115.4 and 43.3 microns in water. Preferential settling of these large particles is likely. (2) The jet-eductor system processed zeolite rapidly generates settled solid yield stresses in excess of 11,000 Pascals in caustic supernates and will not be easily retrieved from Tank 7 with the existing slurry pump technology. (3) Settled size-reduced IE-95 zeolite (less than 38 microns) in caustic supernate does not generate yield stresses in excess of 600 Pascals in less than 30 days. (4) Preferential settling of size-reduced zeolite is a function of the amount of

Enhanced sludge reduction in septic tanks by increasing temperature.

Science.gov (United States)

Pussayanavin, Tatchai; Koottatep, Thammarat; Eamrat, Rawintra; Polprasert, Chongrak

2015-01-01

Septic tanks in most developing countries are constructed without drainage trenches or leaching fields to treat toilet wastewater and /or grey water. Due to the short hydraulic retention time, effluents of these septic tanks are still highly polluted, and there is usually high accumulation of septic tank sludge or septage containing high levels of organics and pathogens that requires frequent desludging and subsequent treatment. This study aimed to reduce sludge accumulation in septic tanks by increasing temperatures of the septic tank content. An experimental study employing two laboratory-scale septic tanks fed with diluted septage and operating at temperatures of 40 and 30°C was conducted. At steady-state conditions, there were more methanogenic activities occurring in the sludge layer of the septic tank operating at the temperature of 40°C, resulting in less total volatile solids (TVS) or sludge accumulation and more methane (CH4) production than in the unit operating at 30°C. Molecular analysis found more abundance and diversity of methanogenic microorganisms in the septic tank sludge operating at 40°C than at 30°C. The reduced TVS accumulation in the 40°C septic tank would lengthen the period of septage removal, resulting in a cost-saving in desluging and septage treatment. Cost-benefit analysis of increasing temperatures in septic tanks was discussed.

SLUDGE RETRIEVAL FROM HANFORD K WEST BASIN SETTLER TANKS

International Nuclear Information System (INIS)

Erpenbeck, E.G.; Leshikar, G.A.

2011-01-01

In 2010, an innovative, remotely operated retrieval system was deployed to successfully retrieve over 99.7% of the radioactive sludge from ten submerged tanks in Hanford's K-West Basin. As part of K-West Basin cleanup, the accumulated sludge needed to be removed from the 0.5 meter diameter by 5 meter long settler tanks and transferred approximately 45 meters to an underwater container for sampling and waste treatment. The abrasive, dense, non-homogeneous sludge was the product of the washing process of corroded nuclear fuel. It consists of small (less than 600 micron) particles of uranium metal, uranium oxide, and various other constituents, potentially agglomerated or cohesive after 10 years of storage. The Settler Tank Retrieval System (STRS) was developed to access, mobilize and pump out the sludge from each tank using a standardized process of retrieval head insertion, periodic high pressure water spray, retraction, and continuous pumping of the sludge. Blind operations were guided by monitoring flow rate, radiation levels in the sludge stream, and solids concentration. The technology developed and employed in the STRS can potentially be adapted to similar problematic waste tanks or pipes that must be remotely accessed to achieve mobilization and retrieval of the sludge within.

Assessment of sludges and tank bottoms treatment processes

International Nuclear Information System (INIS)

Bhutto, A.W.; Bazmi, A.A.

2005-01-01

The petroleum refining industries generate considerable amounts of sludge and tank bottoms as waste. Petroleum refinery receives crude oil containing emulsified water and solids. As the crude oil storage tanks are repeatedly filled and emptied, the water and solids settle towards the bottom as sludge. For tanks that have been in service for several years, the sludge accumulation becomes several feet deep, results in a loss of ullage in refinery crude storage tanks. The accumulation of crude storage tank bottoms is a serious problem experienced by local refineries. The refinery sludge waste is categorized as hazardous waste, which is at present buried in the tankform ground. Since the no hazardous material land filling option available, the disposal of these hazardous materials has become a major problem because of the ISO-14000 certification requirements and expectation of stakeholder. To maximize the waste oil recovery from sludge and tank bottoms and to minimize the volume of the hazardous waste, a number of waste recovery and treatment processes are available. The process designs and unit operations of each process are different and each has its own merits, in terms of the technical complexity, operation friendliness, and costs and economics. A study on each of these technologies and the subsequent tide-up to the existing unit operations is conducted, and the associated technical comparisons are made. (author)

PILOT-SCALE TESTING OF THE SUSPENSION OF MST, CST, AND SIMULATED SLUDGE SLURRIES IN A SLUDGE TANK

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.; Qureshi, Z.; Restivo, M.; Steeper, T.; Williams, M.; Herman, D.

2011-08-02

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Following strontium, actinide, and cesium removal, the concentrated solids will be transported to a sludge tank (i.e., monosodium titanate (MST)/sludge solids to Tank 42H or Tank 51H and crystalline silicotitanate (CST) to Tank 40H) for eventual transfer to the Defense Waste Processing Facility (DWPF). Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for mixing MST, CST, and simulated sludge. The purpose of this pilot scale testing is to determine the pump requirements for mixing MST and CST with sludge in a sludge tank and to determine whether segregation of particles occurs during settling. Tank 40H and Tank 51H have four Quad Volute pumps; Tank 42H has four standard pumps. The pilot-scale tank is a 1/10.85 linear scaled model of Tank 40H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 40H. The pump locations correspond to the current locations in Tank 40H (Risers B2, H, B6, and G). The pumps are pilot-scale Quad Volute pumps. Additional settling tests were conducted in a 30 foot tall, 4 inch inner diameter clear column to investigate segregation of MST, CST, and simulated sludge particles during settling.

Hanford Tank 241-C-106: Residual Waste Contaminant Release Model and Supporting Data

International Nuclear Information System (INIS)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2005-01-01

CH2M HILL is producing risk/performance assessments to support the closure of single-shell tanks at the DOE's Hanford Site. As part of this effort, staff at PNNL were asked to develop release models for contaminants of concern that are present in residual sludge remaining in tank 241-C-106 (C-106) after final retrieval of waste from the tank. This report provides the information developed by PNNL

Rheology of Savannah River site tank 42 HLW radioactive sludge

International Nuclear Information System (INIS)

Ha, B.C.

1997-01-01

Knowledge of the rheology of the radioactive sludge slurries at the Savannah River Site is necessary in order to ensure that they can be retrieved from waste tanks and processed for final disposal. At Savannah River Site, Tank 42 sludge represents on of the first HLW radioactive sludges to be vitrified in the Defense Waste Processing Facility. The rheological properties of unwashed Tank 42 sludge slurries at various solids concentrations were measured remotely in the Shielded Cells at the Savannah River Technology Center using a modified Haake Rotovisco viscometer

Factors influencing suspended solids concentrations in activated sludge settling tanks.

Science.gov (United States)

Kim, Y; Pipes, W O

1999-05-31

A significant fraction of the total mass of sludge in an activated sludge process may be in the settling tanks if the sludge has a high sludge volume index (SVI) or when a hydraulic overload occurs during a rainstorm. Under those conditions, an accurate estimate of the amount of sludge in the settling tanks is needed in order to calculate the mean cell residence time or to determine the capacity of the settling tanks to store sludge. Determination of the amount of sludge in the settling tanks requires estimation of the average concentration of suspended solids in the layer of sludge (XSB) in the bottom of the settling tanks. A widely used reference recommends averaging the concentrations of suspended solids in the mixed liquor (X) and in the underflow (Xu) from the settling tanks (XSB=0. 5{X+Xu}). This method does not take into consideration other pertinent information available to an operator. This is a report of a field study which had the objective of developing a more accurate method for estimation of the XSB in the bottom of the settling tanks. By correlation analysis, it was found that only 44% of the variation in the measured XSB is related to sum of X and Xu. XSB is also influenced by the SVI, the zone settling velocity at X and the overflow and underflow rates of the settling tanks. The method of averaging X and Xu tends to overestimate the XSB. A new empirical estimation technique for XSB was developed. The estimation technique uses dimensionless ratios; i.e., the ratio of XSB to Xu, the ratio of the overflow rate to the sum of the underflow rate and the initial settling velocity of the mixed liquor and sludge compaction expressed as a ratio (dimensionless SVI). The empirical model is compared with the method of averaging X and Xu for the entire range of sludge depths in the settling tanks and for SVI values between 100 and 300 ml/g. Since the empirical model uses dimensionless ratios, the regression parameters are also dimensionless and the model can be

Rheology of Savannah River Site Tank 42 radioactive sludges. Revision 1

International Nuclear Information System (INIS)

Ha, B.C.; Bibler, N.E.

1995-01-01

Knowledge of the rheology of the radioactive sludge slurries at the Savannah River Site (SRS) is necessary in order to ensure that they can be retrieved from waste tanks and processed for final disposal. At Savannah River Site (SRS), Tank 42 sludge represents one of the first HLW radioactive sludges to be vitrified in the Defense Waste Processing Facility (DWPF). The rheological properties of unwashed Tank 42 sludge slurries at various solids concentrations were measured remotely in the Shielded Cells at the Savannah River Technology Center (SRTC) using a modified Haake Rotovisco viscometer. Rheological properties of Tank 42 radioactive sludge were measured as a function of weight percent total solids to ensure that the first DWPF radioactive sludge batch can be pumped and processed in the DWPF with the current design bases. The yield stress and consistency of the sludge slurries were determined by assuming a Bingham plastic fluid model

Tank 241-Z-361 Sludge Retrieval and Treatment Alternatives

International Nuclear Information System (INIS)

HAMPTON, B.K.

2000-01-01

The Plutonium Finishing Plant (PFP) Tank 241-Z-361 (Z-361) contains legacy sludge resulting from waste discharges from past missions at PFP. A sketch of the tank is shown in Figure 1. In this view various risers and penetrations are shown along with the sludge level depicted by the horizontal line halfway up the tank, and the ground level depicted by the horizontal line above the tank. The HEPA filter installed for breathing is also shown on one of the risers

Sludge mobilization with submerged nozzles in horizontal cylindrical tanks

International Nuclear Information System (INIS)

Hylton, T.D.; Cummins, R.L.; Youngblood, E.L.; Perona, J.J.

1995-10-01

The Melton Valley Storage Tanks (MVSTs) and the evaporator service tanks at the Oak Ridge National Laboratory (ORNL) are used for the collection and storage of liquid low-level waste (LLLW). Wastes collected in these tanks are typically acidic when generated and are neutralized with sodium hydroxide to protect the tanks from corrosion; however, the high pH of the solution causes the formation of insoluble compounds that precipitate. These precipitates formed a sludge layer approximately 0.6 to 1.2 m (2 to 4 ft) deep in the bottom of the tanks. The sludge in the MVSTs and the evaporator service tanks will eventually need to be removed from the tanks and treated for final disposal or transferred to another storage facility. The primary options for removing the sludge include single-point sluicing, use of a floating pump, robotic sluicing, and submerged-nozzle sluicing. The objectives of this study were to (1) evaluate the feasibility of submerged-nozzle sluicing in horizontal cylindrical tanks and (2) obtain experimental data to validate the TEMPEST (time-dependent, energy, momentun, pressure, equation solution in three dimensions) computer code

Water washes and caustic leaches of sludge from Hanford Tank S-101 and water washes of sludge from Hanford Tank C-103

International Nuclear Information System (INIS)

Hunt, R.D.; Collins, J.L.; Chase, C.W.

1998-07-01

In 1993, the Department of Energy (DOE) selected the enhanced sludge washing (ESW) process as the baseline for pretreatment of Hanford tank sludges. The ESW process uses a series of water washes and caustic leaches to separate nonradioactive components such as aluminum, chromium, and phosphate from the high-level waste sludges. If the ESW process is successful, the volume of immobilized high-level waste will be significantly reduced. The tests on the sludge from Hanford Tank S-101 focused on the effects of process variables such as sodium hydroxide concentration (1 and 3 M), temperature (70 and 95 C), and leaching time (5, 24, 72, and 168 h) on the efficacy of the ESW process with realistic liquid-to-solid ratios. Another goal of this study was to evaluate the effectiveness of water washes on a sludge sample from hanford Tank C-103. The final objective of this study was to test potential process control monitors during the water washes and caustic leaches with actual sludge. Both 137 Cs activity and conductance were measured for each of the water washes and caustic leaches. Experimental procedures, a discussion of results, conclusions and recommendations are included in this report

Washing and caustic leaching of Hanford tank sludges

International Nuclear Information System (INIS)

Lumetta, G.J.; Rapko, B.M.; Colton, N.G.

1994-01-01

Methods are being developed to treat and dispose of large volumes of radioactive wastes stored in underground tanks at the U.S. Department of Energy's Hanford Site. The wastes will be partitioned into high-level waste (HLW) and low-level waste (LLW) fractions. The HLW will be vitrified into borosilicate glass and disposed of in a geologic repository, while the LLW will be immobilized in a glass matrix and will likely be disposed of by shallow burial at the Hanford Site. The wastes must be pretreated to reduce the volume of the HLW fraction, so that vitrification and disposal costs can be minimized. The current baseline process for pretreating Hanford tank sludges is to leach the sludge under caustic conditions, then remove the solubilized components of the sludge by water washing. Tests of this method have been performed with samples taken from several different tanks at Hanford. The results of these tests are presented in terms of the composition of the sludge before and after leaching. X-ray diffraction and scanning electron microscopy coupled with electron dispersive x-ray techniques have been used to identify the phases in the untreated and treated sludges

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

International Nuclear Information System (INIS)

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

Alternative treatment for septic tank sludge: co-digestion with municipal solid waste in bioreactor landfill simulators.

Science.gov (United States)

Valencia, R; den Hamer, D; Komboi, J; Lubberding, H J; Gijzen, H J

2009-02-01

Co-disposal of septic tank sludge had a positive effect on the municipal solid waste (MSW) stabilisation process in Bioreactor Landfill simulators. Co-disposal experiments were carried out using the Bioreactor Landfill approach aiming to solve the environmental problems caused by indiscriminate and inadequate disposal of MSW and especially of septic tank sludge. The simulator receiving septic tank sludge exhibited a 200 days shorter lag-phase as compared to the 350 days required by the control simulator to start the exponential biogas production. Additionally, the simulator with septic sludge apparently retained more moisture (>60% w/w), which enhanced the overall conversion of organic matter hence increasing the biogas production (0.60 m3 biogas kg(-1)VS(converted)) and removal efficiency of 60% for VS from the simulator. Alkaline pH values (pH>8.5) did not inhibit the biogas production; moreover it contributed to reduce partially the negative effects of NH(4)(+) (>2 g L(-1)) due to NH(3) volatilisation thus reducing the nitrogen content of the residues. Associated risks and hazards with septage disposal were practically eliminated as total coliform and faecal coliform contents were reduced by 99% and 100%, respectively at the end of the experiment. These results indicate that co-disposal has two direct benefits, including the safe and environmentally sound disposal of septic tank sludge and an improvement of the overall performance of the Bioreactor Landfill by increasing moisture retention and supplying a more acclimatised bacterial population.

Contaminant Release from Residual Waste in Closed Single-Shell Tanks and Other Waste Forms Associated with the Tanks

International Nuclear Information System (INIS)

Deutsch, William J.

2008-01-01

This chapter describes the release of contaminants from the various waste forms that are anticipated to be associated with closure of the single-shell tanks. These waste forms include residual sludge or saltcake that will remain in the tanks after waste retrieval. Other waste forms include engineered glass and cementitious materials as well as contaminated soil impacted by previous tank leaks. This chapter also describes laboratory testing to quantify contaminant release and how the release data are used in performance/risk assessments for the tank waste management units and the onsite waste disposal facilities. The chapter ends with a discussion of the surprises and lessons learned to date from the testing of waste materials and the development of contaminant release models

Computer modeling of ORNL storage tank sludge mobilization and mixing

International Nuclear Information System (INIS)

Terrones, G.; Eyler, L.L.

1993-09-01

This report presents and analyzes the results of the computer modeling of mixing and mobilization of sludge in horizontal, cylindrical storage tanks using submerged liquid jets. The computer modeling uses the TEMPEST computational fluid dynamics computer program. The horizontal, cylindrical storage tank configuration is similar to the Melton Valley Storage Tanks (MVST) at Oak Ridge National (ORNL). The MVST tank contents exhibit non-homogeneous, non-Newtonian rheology characteristics. The eventual goals of the simulations are to determine under what conditions sludge mobilization using submerged liquid jets is feasible in tanks of this configuration, and to estimate mixing times required to approach homogeneity of the contents of the tanks

Bench-scale enhanced sludge washing and gravity settling of Hanford Tank C-106 Sludge

International Nuclear Information System (INIS)

Brooks, K.P.; Myers, R.L.; Rappe, K.G.

1997-01-01

This report summarizes the results of a bench-scale sludge pretreatment demonstration of the Hanford baseline flowsheet using liter-quantities of sludge from Hanford Site single-shell tank 241-C-106 (tank C-106). The leached and washed sludge from these tests provided Envelope D material for the contractors supporting Tank Waste Remediation System (TWRS) Privatization. Pretreatment of the sludge included enhanced sludge washing and gravity settling tests and providing scale-up data for both these unit operations. Initial and final solids as well as decanted supernatants from each step of the process were analyzed chemically and radiochemically. The results of this work were compared to those of Lumetta et al. (1996a) who performed a similar experiment with 15 grams of C-106, sludge. A summary of the results are shown in Table S.1. Of the major nonradioactive components, those that were significantly removed with enhanced sludge washing included aluminum (31%), chromium (49%), sodium (57%), and phosphorus (35%). Of the radioactive components, a significant amount of 137 Cs (49%) were removed during the enhanced sludge wash. Only a very small fraction of the remaining radionuclides were removed, including 90 Sr (0.4%) and TRU elements (1.5%). These results are consistent with those of the screening test. All of the supernatants (both individually and as a blend) removed from these washing steps, once vitrified as LLW glasses (at 20 wt% Na 2 O), would be less than NRC Class C in TRU elements and less than NRC Class B in 90 Sr

Characterization and decant of Tank 42H sludge sample ESP-200

International Nuclear Information System (INIS)

Hay, M.S.

2000-01-01

DWPF Engineering requested that the Savannah River Technology Center (SRTC) provide a demonstration of the DWPF flowsheet on sludge from Tank 42H in the Shielded Cell facility. A 5 liter sample of the Tank 42H sludge (ESP-200), obtained with the tank contents fully mixed, arrived at SRTC on January 20, 1998. This report details receipt of the 5 liter sample at SRTC, the decant of the sample, and the characterization of the pre- and post-decant Tank 42H sludge. Evaluation of the measured composition of the supernate indicates Sample ESP-200 became diluted approximately 20 percent by volume prior to receipt. This dilution complicates the relationship of the characterization of Post-Decant ESP-200 to the current contents of Tank 42H. For the purposes of modeling the current tank contents of Tank 42H, this report provides an estimated composition based on analytical data of recent samples from Tank 42H

Characterization and decant of Tank 42H sludge sample ESP-200

Energy Technology Data Exchange (ETDEWEB)

Hay, M.S.

2000-04-25

DWPF Engineering requested that the Savannah River Technology Center (SRTC) provide a demonstration of the DWPF flowsheet on sludge from Tank 42H in the Shielded Cell facility. A 5 liter sample of the Tank 42H sludge (ESP-200), obtained with the tank contents fully mixed, arrived at SRTC on January 20, 1998. This report details receipt of the 5 liter sample at SRTC, the decant of the sample, and the characterization of the pre- and post-decant Tank 42H sludge. Evaluation of the measured composition of the supernate indicates Sample ESP-200 became diluted approximately 20 percent by volume prior to receipt. This dilution complicates the relationship of the characterization of Post-Decant ESP-200 to the current contents of Tank 42H. For the purposes of modeling the current tank contents of Tank 42H, this report provides an estimated composition based on analytical data of recent samples from Tank 42H.

TESTING OF ENHANCED CHEMICAL CLEANING OF SRS ACTUAL WASTE TANK 5F AND TANK 12H SLUDGES

Energy Technology Data Exchange (ETDEWEB)

Martino, C.; King, W.

2011-08-22

Forty three of the High Level Waste (HLW) tanks at the Savannah River Site (SRS) have internal structures that hinder removal of the last approximately five thousand gallons of waste sludge solely by mechanical means. Chemical cleaning can be utilized to dissolve the sludge heel with oxalic acid (OA) and pump the material to a separate waste tank in preparation for final disposition. This dissolved sludge material is pH adjusted downstream of the dissolution process, precipitating the sludge components along with sodium oxalate solids. The large quantities of sodium oxalate and other metal oxalates formed impact downstream processes by requiring additional washing during sludge batch preparation and increase the amount of material that must be processed in the tank farm evaporator systems and the Saltstone Processing Facility. Enhanced Chemical Cleaning (ECC) was identified as a potential method for greatly reducing the impact of oxalate additions to the SRS Tank Farms without adding additional components to the waste that would extend processing or increase waste form volumes. In support of Savannah River Site (SRS) tank closure efforts, the Savannah River National Laboratory (SRNL) conducted Real Waste Testing (RWT) to evaluate an alternative to the baseline 8 wt. % OA chemical cleaning technology for tank sludge heel removal. The baseline OA technology results in the addition of significant volumes of oxalate salts to the SRS tank farm and there is insufficient space to accommodate the neutralized streams resulting from the treatment of the multiple remaining waste tanks requiring closure. ECC is a promising alternative to bulk OA cleaning, which utilizes a more dilute OA (nominally 2 wt. % at a pH of around 2) and an oxalate destruction technology. The technology is being adapted by AREVA from their decontamination technology for Nuclear Power Plant secondary side scale removal. This report contains results from the SRNL small scale testing of the ECC process

Hanford Tanks 241-C-203 and 241-C-204: Residual Waste Contaminant Release Model and Supporting Data

Energy Technology Data Exchange (ETDEWEB)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2004-10-28

This report describes the development of release models for key contaminants that are present in residual sludge remaining after closure of Hanford Tanks 241-C-203 (C-203) and 241-C-204 (C-204). The release models were developed from data generated by laboratory characterization and testing of samples from these two tanks. Key results from this work are (1) future releases from the tanks of the primary contaminants of concern (99Tc and 238U) can be represented by relatively simple solubility relationships between infiltrating water and solid phases containing the contaminants; and (2) high percentages of technetium-99 in the sludges (20 wt% in C-203 and 75 wt% in C-204) are not readily water leachable, and, in fact, are very recalcitrant. This is similar to results found in related studies of sludges from Tank AY-102. These release models are being developed to support the tank closure risk assessments performed by CH2M HILL Hanford Group, Inc., for the U.S. Department of Energy.

Hanford Tanks 241-C-203 and 241-C-204: Residual Waste Contaminant Release Model and Supporting Data

International Nuclear Information System (INIS)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2004-01-01

This report describes the development of release models for key contaminants that are present in residual sludge remaining after closure of Hanford Tanks 241-C-203 (C-203) and 241-C-204 (C-204). The release models were developed from data generated by laboratory characterization and testing of samples from these two tanks. Key results from this work are (1) future releases from the tanks of the primary contaminants of concern (99Tc and 238U) can be represented by relatively simple solubility relationships between infiltrating water and solid phases containing the contaminants; and (2) high percentages of technetium-99 in the sludges (20 wt% in C-203 and 75 wt% in C-204) are not readily water leachable, and, in fact, are very recalcitrant. This is similar to results found in related studies of sludges from Tank AY-102. These release models are being developed to support the tank closure risk assessments performed by CH2M HILL Hanford Group, Inc., for the U.S. Department of Energy

Sludge pretreatment chemistry evaluation: Enhanced sludge washing separation factors

International Nuclear Information System (INIS)

Colton, N.G.

1995-03-01

This report presents the work conducted in Fiscal Year 1994 by the Sludge Pretreatment Chemistry Evaluation Subtask for the Tank Waste Remediation System (TWRS) Tank Waste Treatment Science Task. The main purpose of this task, is to provide the technical basis and scientific understanding to support TWRS baseline decisions and actions, such as the development of an enhanced sludge washing process to reduce the volume of waste that will require high-level waste (HLW) vitrification. One objective within the Sludge Pretreatment Chemistry Evaluation Subtask was to establish wash factors for various SST (single-shell tank) sludges. First, analytical data were compiled from existing tank waste characterization reports. These data were summarized on tank-specific worksheets that provided a uniform format for reviewing and comparing data, as well as the means to verify whether the data set for each tank was complete. Worksheets were completed for 27 SST wastes. The analytical water wash data provided tank-specific information about the fraction of each component that dissolves with water, i.e., an estimate of tank-specific wash factors for evaluating tank-by-tank processing. These wash data were then used collectively to evaluate some of the wash factors that are assumed for the overall SST waste inventory; specifically, wash factors for elements that would be found primarily in sludges. The final step in this study was to incorporate the characterization and wash factor data into a spreadsheet that provides insight into the effect of enhanced sludge washing on individual tank sludges as well as for groups of sludges that may be representative of different waste types. Spreadsheet results include the estimated mass and percentage of each element that would be removed with washing and leaching. Furthermore, estimated compositions are given of the final wash and leach streams and residual solids, in terms of both concentration and dry weight percent

Results of Sludge Mobilization Testing at Hanford High Level Waste (HLW) Tank

International Nuclear Information System (INIS)

STAEHR, T.W.

2001-01-01

Waste stored in the Tank 241-AZ-101 at the US DOE Hanford is scheduled as the initial feed for high-level waste vitrification. Tank 241-AZ-101 currently holds over 3,000,000 liters of waste made up of a settled sludge layer covered by a layer of liquid supernant. To retrieve the waste from the tank, it is necessary to mobilize and suspend the settled sludge so that the resulting slurry can be pumped from the tank for treatment and vitrification. Two 223.8-kilowatt mixer pumps have been installed in Tank 241-AZ-101 to mobilize the settled sludge layer of waste for retrieval. In May of 2000, the mixer pumps were subjected to a series of tests to determine (1) the extent to which the mixer pumps could mobilize the settle sludge layer of waste, (2) if the mixer pumps could function within operating parameters, and (3) if state-of-the-art monitoring equipment could effectively monitor and quantify the degree of sludge mobilization and suspension. This paper presents the major findings and results of the Tank 241-AZ-101 mixer pump tests, based on analysis of data and waste samples that were collected during the testing. Discussion of the results focuses on the effective cleaning radius achieved and the volume and concentration of sludge mobilized, with both one and two pumps operating in various configurations and speeds. The Tank 241-AZ-101 mixer pump tests were unique in that sludge mobilization parameters were measured using actual waste in an underground storage tank at the hanford Site. The methods and instruments that were used to measure waste mobilization parameters in Tank 241-AZ-101 can be used in other tanks. It can be concluded from the testing that the use of mixer pumps is an effective retrieval method for the mobilization of settled solids in Tank 241-AZ-101

Status Report on Phase Identification in Hanford Tank Sludges

International Nuclear Information System (INIS)

Rapko, B.M.; Lumetta, G.J.

2000-01-01

The US Department of Energy plans to vitrify Hanford's tank wastes. The vitrified wastes will be divided into low-activity and high-level fractions. There is an effort to reduce the quantity of high-activity wastes by removing nonradioactive components because of the high costs involved in treating high-level waste. Pretreatment options, such as caustic leaching, to selectively remove nonradioactive components are being investigated. The effectiveness of these proposed processes for removing nonradioactive components depends on the chemical phases in the tank sludges. This review summarizes the chemical phases identified to date in Hanford tank sludges

Low-pressure hydraulic technique for slurrying radioactive sludges in waste tanks

International Nuclear Information System (INIS)

Bradley, R.F.; Parsons, F.A.; Goodlett, C.B.; Mobley, R.M.

1977-11-01

Present technology for the removal of sludges from radioactive liquid waste storage tanks at the Savannah River Plant (SRP) requires large volumes of fresh water added through high-pressure (approx.3000 psig) nozzles positioned to resuspend and slurry the sludge. To eliminate the cost of storing and evaporating these large volumes of water (several hundred thousand gallons per tank cleaned), a technique was developed at the Savannah River Laboratory (SRL) to use recirculating, radioactive, supernate solution to resuspend the sludge. The system consists in part of a single-stage centrifugal pump operating in the sludge at approx.100 psia. Recirculating supernate is drawn into the bottom of the pump and forced out through two oppositely directed nozzles to give liquid jets with a sludge-slurrying capability equal to that obtained with the present high-pressure system. In addition to eliminating the addition of large quantities of water to the tanks, the low-pressure recirculating technique requires only approximately one-sixth of the power required by the high-pressure system. Test results with clay (as a simulant for sludge) in a waste tank mockup confirmed theoretical predictions that jets with the same momentum gave essentially the same sludge-slurrying patterns. The effective cleaning radius of the recirculating jet was directly proportional to the product of the nozzle velocity and the nozzle diameter (U 0 D). At the maximum U 0 D developed by the pump (approx.14 ft 2 /s), the effective cleaning radius in the tank mockup was approx.20 feet

Plant available nitrogen from anaerobically digested sludge and septic tank sludge applied to crops grown in the tropics.

Science.gov (United States)

Sripanomtanakorn, S; Polprasert, C

2002-04-01

Agricultural land is an attractive alternative for the disposal of biosolids since it utilises the recyclable nutrients in the production of crops. In Thailand and other tropical regions, limited field-study information exists on the effect of biosolids management strategies on crop N utilisation and plant available N (PAN) of biosolids. A field study was conducted to quantify the PAN of the applied biosolids, and to evaluate the N uptake rates of some tropical crops. Sunflower (Helianthus annuus) and tomato (Lycopersicon esculentum) were chosen in this study. Two types of biosolids used were: anaerobically digested sludge and septic tank sludge. The soil is acid sulfate and is classified as Sulfic Tropaquepts with heavy clay in texture. The anaerobically digested sludge applied rates were: 0, 156 and 312 kg N ha(-1) for the sunflower plots, and 0, 586, and 1172 kg N ha(-1) for the tomato plots. The septic tank sludge applied rates were: 0, 95 and 190 kg N ha(-1) for the sunflower plots, and 0, 354 and 708 kg N ha(-1) for the tomato plots, respectively. The results indicated the feasibility of applying biosolids to grow tropical crops. The applications of the anaerobically digested sludge and the septic tank sludge resulted in the yields of sunflower seeds and tomato fruits and the plant N uptakes comparable or better than that applied with only the chemical fertiliser. The estimated PAN of the anaerobically digested sludge was about 27-42% of the sludge organic N during the growing season. For the septic tank sludge, the PAN was about 15-58% of the sludge organic N. It is interesting to observe that an increase of the rate of septic tank sludge incorporated into this heavy clay soil under the cropping system resulted in the decrease of N mineralisation rate. This situation could cause the reduction of yield and N uptake of crops.

Gas composition of sludge residue profiles in a sludge treatment reed bed between loadings.

Science.gov (United States)

Larsen, Julie D; Nielsen, Steen M; Scheutz, Charlotte

2017-11-01

Treatment of sludge in sludge treatment reed bed systems includes dewatering and mineralization. The mineralization process, which is driven by microorganisms, produces different gas species as by-products. The pore space composition of the gas species provides useful information on the biological processes occurring in the sludge residue. In this study, we measured the change in composition of gas species in the pore space at different depth levels in vertical sludge residue profiles during a resting period of 32 days. The gas composition of the pore space in the sludge residue changed during the resting period. As the resting period proceeded, atmospheric air re-entered the pore space at all depth levels. The methane (CH 4 ) concentration was at its highest during the first part of the resting period, and then declined as the sludge residue became more dewatered and thereby aerated. In the pore space, the concentration of CH 4 often exceeded the concentration of carbon dioxide (CO 2 ). However, the total emission of CO 2 from the surface of the sludge residue exceeded the total emission of CH 4 , suggesting that CO 2 was mainly produced in the layer of newly applied sludge and/or that CO 2 was emitted from the sludge residue more readily compared to CH 4 .

Characterization of tank 51 sludge samples (HTF-51-17-44/ HTF-51-17-48) in support of sludge batch 10 processing

Energy Technology Data Exchange (ETDEWEB)

Oji, L. N. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-08-17

The Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (SRR) Engineering (SRR-E) to provide sample characterization and analyses of Tank 51 sludge samples in support of Sludge Batch (SB) 10. The two Tank 51 sludge samples were sampled and delivered to SRNL in May of 2017. These two tank 51 sludge samples were combined into one composite sample and analyzed for corrosion controls analytes, select radionuclides, chemical elements, density and weight percent total solids and aluminum hydroxides (gibbsite and boehmite) by x-ray diffraction.

HIGH LEVEL WASTE MECHANCIAL SLUDGE REMOVAL AT THE SAVANNAH RIVER SITE F TANK FARM CLOSURE PROJECT

International Nuclear Information System (INIS)

Jolly, R; Bruce Martin, B

2008-01-01

The Savannah River Site F-Tank Farm Closure project has successfully performed Mechanical Sludge Removal (MSR) using the Waste on Wheels (WOW) system for the first time within one of its storage tanks. The WOW system is designed to be relatively mobile with the ability for many components to be redeployed to multiple waste tanks. It is primarily comprised of Submersible Mixer Pumps (SMPs), Submersible Transfer Pumps (STPs), and a mobile control room with a control panel and variable speed drives. In addition, the project is currently preparing another waste tank for MSR utilizing lessons learned from this previous operational activity. These tanks, designated as Tank 6 and Tank 5 respectively, are Type I waste tanks located in F-Tank Farm (FTF) with a capacity of 2,840 cubic meters (750,000 gallons) each. The construction of these tanks was completed in 1953, and they were placed into waste storage service in 1959. The tank's primary shell is 23 meters (75 feet) in diameter, and 7.5 meters (24.5 feet) in height. Type I tanks have 34 vertically oriented cooling coils and two horizontal cooling coil circuits along the tank floor. Both Tank 5 and Tank 6 received and stored F-PUREX waste during their operating service time before sludge removal was performed. DOE intends to remove from service and operationally close (fill with grout) Tank 5 and Tank 6 and other HLW tanks that do not meet current containment standards. Mechanical Sludge Removal, the first step in the tank closure process, will be followed by chemical cleaning. After obtaining regulatory approval, the tanks will be isolated and filled with grout for long-term stabilization. Mechanical Sludge Removal operations within Tank 6 removed approximately 75% of the original 95,000 liters (25,000 gallons). This sludge material was transferred in batches to an interim storage tank to prepare for vitrification. This operation consisted of eleven (11) Submersible Mixer Pump(s) mixing campaigns and multiple intraarea

HIGH LEVEL WASTE MECHANCIAL SLUDGE REMOVAL AT THE SAVANNAH RIVER SITE F TANK FARM CLOSURE PROJECT

Energy Technology Data Exchange (ETDEWEB)

Jolly, R; Bruce Martin, B

2008-01-15

The Savannah River Site F-Tank Farm Closure project has successfully performed Mechanical Sludge Removal (MSR) using the Waste on Wheels (WOW) system for the first time within one of its storage tanks. The WOW system is designed to be relatively mobile with the ability for many components to be redeployed to multiple waste tanks. It is primarily comprised of Submersible Mixer Pumps (SMPs), Submersible Transfer Pumps (STPs), and a mobile control room with a control panel and variable speed drives. In addition, the project is currently preparing another waste tank for MSR utilizing lessons learned from this previous operational activity. These tanks, designated as Tank 6 and Tank 5 respectively, are Type I waste tanks located in F-Tank Farm (FTF) with a capacity of 2,840 cubic meters (750,000 gallons) each. The construction of these tanks was completed in 1953, and they were placed into waste storage service in 1959. The tank's primary shell is 23 meters (75 feet) in diameter, and 7.5 meters (24.5 feet) in height. Type I tanks have 34 vertically oriented cooling coils and two horizontal cooling coil circuits along the tank floor. Both Tank 5 and Tank 6 received and stored F-PUREX waste during their operating service time before sludge removal was performed. DOE intends to remove from service and operationally close (fill with grout) Tank 5 and Tank 6 and other HLW tanks that do not meet current containment standards. Mechanical Sludge Removal, the first step in the tank closure process, will be followed by chemical cleaning. After obtaining regulatory approval, the tanks will be isolated and filled with grout for long-term stabilization. Mechanical Sludge Removal operations within Tank 6 removed approximately 75% of the original 95,000 liters (25,000 gallons). This sludge material was transferred in batches to an interim storage tank to prepare for vitrification. This operation consisted of eleven (11) Submersible Mixer Pump(s) mixing campaigns and multiple

Gas composition of sludge residue profiles in a sludge treatment reed bed between loadings

DEFF Research Database (Denmark)

Larsen, Julie Dam; Nielsen, Steen M; Scheutz, Charlotte

2017-01-01

Treatment of sludge in sludge treatment reed bed systems includes dewatering and mineralization. The mineralization process, which is driven by microorganisms, produces different gas species as by-products. The pore space composition of the gas species provides useful information on the biological...... processes occurring in the sludge residue. In this study, we measured the change in composition of gas species in the pore space at different depth levels in vertical sludge residue profiles during a resting period of 32 days. The gas composition of the pore space in the sludge residue changed during...

Case study to remove radioactive hazardous sludge from long horizontal storage tanks

International Nuclear Information System (INIS)

Hylton, T.D.; Youngblood, E.L.; Cummins, R.L.

1995-01-01

The removal of radioactive hazardous sludge from waste tanks is a significant problem at several US Department of Energy (DOE) sites. The use of submerged jets produced by mixing pumps lowered into the supernatant/sludge interface to produce a homogeneous slurry is being studied at several DOE facilities. The homogeneous slurry can be pumped from the tanks to a treatment facility or alternative storage location. Most of the previous and current studies with this method are for flat-bottom tanks with vertical walls. Because of the difference in geometry, the results of these studies are not directly applicable to long horizontal tanks such as those used at the Oak Ridge National Laboratory. Mobilization and mixing studies were conducted with a surrogate sludge (e.g., kaolin clay) using submerged jets in two sizes of horizontal tanks. The nominal capacities of these tanks were 0.87 m 3 (230 gal) and 95 m 3 (25,000 gal). Mobilization efficiencies and mixing times were determined for single and bidirectional jets in both tanks with the discharge nozzles positioned at two locations in the tanks. Approximately 80% of the surrogate sludge was mobilized in the 95-m 3 tank using a fixed bidirectional jet (inside diameter = 0.035 m) and a jet velocity of 6.4 m/s (21 ft/s)

High level caves rheological studies of tanks 15H, 42H, and 8F sludge/slurries

International Nuclear Information System (INIS)

Hamm, B.A.

1984-01-01

Samples of sludge were diluted to varying solids loading with salt-supernate, deionized water or pH 12 solution (0.01M NaOH). Rheological and physical property determinations were made. There was not a large change in rhelogical properties of sludge following aluminum dissolution, and a dissolved solids contribution to yield stress was not observed. The tank 15/42 and GIW-79 sludges had aluminum concentrations from 14 to 28 wt %. The tank 8 and GIW-82 sludges had aluminum concentrations from 6 to 8 wt %. The high aluminum sludges showed a more rapid increase in yield stress as a function of insoluble solids than the low aluminum sludges. The synthetic sludge formulation used in the GIW-79 study was a fairly good match for tank 15/42 sludge and the GIW-82 formulation was a fairly food match for tank 8 sludge when comparing yield stress and consistency relationship to insoluble solids. The tank 15/42 results indicate a yield stress of about 200 dynes/cm 2 at 13 wt % insoluble solids. The tank 8 results show a yield stress of about 80 dynes/cm 2 at 19 wt % insoluble solids. The calculational procedure used yields a conservative upper limit on the value of yield stress. For sludge transfer from F to H-area (30 to 50 dynes/cm 2 ), the tank 8 sludge concentration range was 3 to 18 wt % insoluble solids. For transfer from H to S-area (30 to 100 dynes/cm 2 ), the tank 8 concentration range was 3 to 22 wt % insoluble solids and the tank 15/42 range was found to be 6 to 11 wt % insoluble solids

Sludge accumulation and conversion to methane in a septic tank treating domestic wastewater or black water.

Science.gov (United States)

Elmitwalli, Tarek

2013-01-01

Although the septic tank is the most applied on-site system for wastewater pre-treatment, limited research has been performed to determine sludge accumulation and biogas production in the tank. Therefore a dynamic mathematical model based on the Anaerobic Digestion Model No. 1 (ADM1) was developed for anaerobic digestion of the accumulated sludge in a septic tank treating domestic wastewater or black water. The results showed that influent chemical oxygen demand (COD) concentration and hydraulic retention time (HRT) of the tank mainly control the filling time with sludge, while operational temperature governs characteristics of the accumulated sludge and conversion to methane. For obtaining stable sludge and high conversion, the tank needs to be operated for a period more than a year without sludge wasting. Maximum conversion to methane in the tank is about 50 and 60% for domestic wastewater and black water, respectively. The required period for sludge wasting depends on the influent COD concentration and the HRT, while characteristics of the wasted sludge are affected by operational temperature followed by the influent COD concentration and the HRT. Sludge production from the tank ranges between 0.19 to 0.22 and 0.13 to 0.15 L/(person.d), for the domestic wastewater and black water, respectively.

Washing and caustic leaching of Hanford tank sludge: Results of FY 1997 studies

International Nuclear Information System (INIS)

Lumetta, G.J.; Burgeson, I.E.; Wagner, M.J.; Liu, J.; Chen, Y.L.

1997-08-01

The current plan for remediating the Hanford tank farms consists of waste retrieval, pretreatment, treatment (immobilization), and disposal. The tank wastes will be partitioned into high-level and low-level fractions. The HLW will be immobilized in a borosilicate glass matrix; the resulting glass canisters will then be disposed of in a geologic repository. Because of the expected high cost of HLW vitrification and geologic disposal, pretreatment processes will be implemented to reduce the volume of immobilized high-level waste (IHLW). Caustic leaching (sometimes referred to as enhanced sludge washing or ESW) represents the baseline method for pretreating Hanford tank sludges. Caustic leaching is expected to remove a large fraction of the Al, which is present in large quantities in Hanford tank sludges. A significant portion of the P is also expected to be removed from the sludge by metathesis of water-insoluble metal phosphates to insoluble hydroxides and soluble Na 3 PO 4 . Similar metathesis reactions can occur for insoluble sulfate salts, allowing the removal of sulfate from the HLW stream. This report describes the sludge washing and caustic leaching tests performed at the Pacific Northwest National Laboratory in FY 1996. The sludges used in this study were taken from Hanford tanks AN-104, BY-108, S-101, and S-111

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

International Nuclear Information System (INIS)

Spence, R.D.; Kauschinger, J.L.

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. This 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

Basic and acidic leaching of Melton Valley Storage Tank sludge at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Collins, J.L.; Egan, B.Z.; Beahm, E.C.

1995-01-01

Basic and acidic leaching tests were conducted with samples of sludge taken from an underground storage tank at the US Department of Energy Melton Valley Storage Tank facility at Oak Ridge National Laboratory. The tests evaluated separation technologies for use in sludge processing to concentrate the radionuclides and reduce the volumes of storage tank waste for final disposal. Study results of sludge characterization, caustic leaching of sludge samples at ambient temperature and at 95 degrees C, and acid leaching of sludge samples at ambient temperature are reported in detail

Characterization, Leaching, and Filtrations Testing of Ferrocyanide Tank sludge (Group 8) Actual Waste Composite

International Nuclear Information System (INIS)

Fiskum, Sandra K.; Billing, Justin M.; Crum, J.V.; Daniel, Richard C.; Edwards, Matthew K.; Shimskey, Rick W.; Peterson, Reid A.; MacFarlan, Paul J.; Buck, Edgar C.; Draper, Kathryn E.; Kozelisky, Anne E.

2009-01-01

This is the final report in a series of eight reports defining characterization, leach, and filtration testing of a wide variety of Hanford tank waste sludges. The information generated from this series is intended to supplement the Waste Treatment and Immobilization Plant (WTP) project understanding of actual waste behaviors associated with tank waste sludge processing through the pretreatment portion of the WTP. The work described in this report presents information on a high-iron waste form, specifically the ferrocyanide tank waste sludge. Iron hydroxide has been shown to pose technical challenges during filtration processing; the ferrocyanide tank waste sludge represented a good source of the high-iron matrix to test the filtration processing

Characterization, Leaching, and Filtrations Testing of Ferrocyanide Tank sludge (Group 8) Actual Waste Composite

Energy Technology Data Exchange (ETDEWEB)

Fiskum, Sandra K.; Billing, Justin M.; Crum, J. V.; Daniel, Richard C.; Edwards, Matthew K.; Shimskey, Rick W.; Peterson, Reid A.; MacFarlan, Paul J.; Buck, Edgar C.; Draper, Kathryn E.; Kozelisky, Anne E.

2009-02-28

This is the final report in a series of eight reports defining characterization, leach, and filtration testing of a wide variety of Hanford tank waste sludges. The information generated from this series is intended to supplement the Waste Treatment and Immobilization Plant (WTP) project understanding of actual waste behaviors associated with tank waste sludge processing through the pretreatment portion of the WTP. The work described in this report presents information on a high-iron waste form, specifically the ferrocyanide tank waste sludge. Iron hydroxide has been shown to pose technical challenges during filtration processing; the ferrocyanide tank waste sludge represented a good source of the high-iron matrix to test the filtration processing.

Feasibility report on criticality issues associated with storage of K Basin sludge in tanks farms

Energy Technology Data Exchange (ETDEWEB)

Vail, T.S.

1997-05-29

This feasibility study provides the technical justification for conclusions about K Basin sludge storage options. The conclusions, solely based on criticality safety considerations, depend on the treatment of the sludge. The two primary conclusions are, (1) untreated sludge must be stored in a critically safe storage tank, and (2) treated sludge (dissolution, precipitation and added neutron absorbers) can be stored in a standard Double Contained Receiver Tank (DCRT) or 241-AW-105 without future restrictions on tank operations from a criticality safety perspective.

Feasibility report on criticality issues associated with storage of K Basin sludge in tanks farms

International Nuclear Information System (INIS)

Vail, T.S.

1997-01-01

This feasibility study provides the technical justification for conclusions about K Basin sludge storage options. The conclusions, solely based on criticality safety considerations, depend on the treatment of the sludge. The two primary conclusions are, (1) untreated sludge must be stored in a critically safe storage tank, and (2) treated sludge (dissolution, precipitation and added neutron absorbers) can be stored in a standard Double Contained Receiver Tank (DCRT) or 241-AW-105 without future restrictions on tank operations from a criticality safety perspective

Characterization of Tank 51 Sludge Slurry Samples (HTF-51-17-67, -68, -69, -74, -75, and -76) in Support of Sludge Batch 10 Processing

Energy Technology Data Exchange (ETDEWEB)

Oji, L. N. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Reboul, S. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-11-09

The Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (SRR) Engineering (SRR-E) to provide sample characterization and analyses of Tank 51 sludge samples in support of Sludge Batch (SB) 10. The six Tank 51 sludge samples were sampled and delivered to SRNL in August of 2017. These six Tank 51 sludge samples, after undergoing physical characterizations which included rheology, weight percent total solid, dissolved solids and density measurements, were combined into one composite Tank 51 sample and analyzed for corrosion controls analytes, select radionuclides, chemical elements, density and weight percent total solids.

Correlation models for waste tank sludges and slurries

International Nuclear Information System (INIS)

Mahoney, L.A.; Trent, D.S.

1995-07-01

This report presents the results of work conducted to support the TEMPEST computer modeling under the Flammable Gas Program (FGP) and to further the comprehension of the physical processes occurring in the Hanford waste tanks. The end products of this task are correlation models (sets of algorithms) that can be added to the TEMPEST computer code to improve the reliability of its simulation of the physical processes that occur in Hanford tanks. The correlation models can be used to augment, not only the TEMPEST code, but other computer codes that can simulate sludge motion and flammable gas retention. This report presents the correlation models, also termed submodels, that have been developed to date. The submodel-development process is an ongoing effort designed to increase our understanding of sludge behavior and improve our ability to realistically simulate the sludge fluid characteristics that have an impact on safety analysis. The effort has employed both literature searches and data correlation to provide an encyclopedia of tank waste properties in forms that are relatively easy to use in modeling waste behavior. These properties submodels will be used in other tasks to simulate waste behavior in the tanks. Density, viscosity, yield strength, surface tension, heat capacity, thermal conductivity, salt solubility, and ammonia and water vapor pressures were compiled for solutions and suspensions of sodium nitrate and other salts (where data were available), and the data were correlated by linear regression. In addition, data for simulated Hanford waste tank supernatant were correlated to provide density, solubility, surface tension, and vapor pressure submodels for multi-component solutions containing sodium hydroxide, sodium nitrate, sodium nitrite, and sodium aluminate

Effect of micro-aeration on anaerobic digestion of primary sludge under septic tank conditions.

Science.gov (United States)

Diak, James; Örmeci, Banu; Kennedy, Kevin J

2013-04-01

Micro-aeration, which refers to the addition of very small amounts of air, is a simple technology that can potentially be incorporated in septic tanks to improve the digestion performance. The purpose of this study was to investigate and compare the effects of micro-aeration on anaerobic digestion of primary sludge under septic tank conditions. 1.6 L batch reactor experiments were carried out in duplicate using raw primary sludge, with 4.1 % total solids, and diluted primary sludge, with 2.1 % total solids. Reactors were operated for 5 weeks at room temperature to simulate septic tank conditions. Micro-aeration rate of 0.00156 vvm effectively solubilised chemical oxygen demand (COD) and improved the subsequent degradation of COD. Micro-aeration also increased the generation of ammonia and soluble proteins, but did not improve the reduction in total and volatile solids, or the reduction in carbohydrates. Experiments using diluted sludge samples showed similar trends as the experiments with raw sludge, which suggest that initial solids concentration did not have a significant effect on the degradation of primary sludge under septic tank conditions.

Basis for Selection of a Residual Waste Retrieval System for Gunite and Associated Tank W-9 at the Oak Ridge National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Lewis, B.E

2000-10-23

Waste retrieval and transfer operations at the Gunite{trademark} and Associated Tanks (GAATs) Remediation Project have been successfully accomplished using the Tank Waste Retrieval System. This system is composed of the Modified Light-Duty Utility Arm, Houdini Vehicle, Waste Dislodging and Conveyance System, Hose Management Arm, and Sludge Conditioning System. GAAT W-9 has been used as a waste-consolidation and batch-transfer tank during the retrieval of sludges and supernatants from the seven Gunite tanks in the North and South tank farms at Oak Ridge National Laboratory. Tank W-9 was used as a staging tank for the transfers to the Melton Valley Storage Tanks (MVSTs). A total of 18 waste transfers from W-9 occurred between May 25, 1999, and March 30, 2000. Most of these transfers were accomplished using the PulsAir Mixer to mobilize and mix the slurry and a submersible retrieval-transfer pump to transfer the slurry through the Sludge Conditioning System and the {approx}1-mile long, 2-in.-diam waste-transfer line to the MVSTs. The transfers from W-9 have consisted of low-solids-content slurries with solids contents ranging from {approx}2.8 to 6.8 mg/L. Of the initial {approx}88,000 gal of wet sludge estimated in the GAATs, a total of {approx}60,451 gal have been transferred to the MVSTs via tank W-9 as of March 30, 2000. Once the waste-consolidation operations and transfers from W-9 to the MVSTs are completed, the remaining material in W-9 will be mobilized and transferred to the active waste system, Bethel Valley Evaporator Service Tank W-23. Tank W-23 will serve as a batch tank for the final waste transfers from tank W-9 to the MVSTs. This report provides a summary of the requirements and recommendations for the final waste retrieval system for tank W-9, a compilation of the sample analysis data for the sludge in W-9, and brief descriptions of the various waste-retrieval system concepts that were considered for this task. The recommended residual waste retrieval

Characterization and leaching study of sludge from Melton Valley Storage Tank W-25

International Nuclear Information System (INIS)

Collins, J.L.; Egan, B.Z.; Beahm, E.C.; Chase, C.W.; Anderson, K.K.

1997-08-01

One of the greatest challenges facing the Department of Energy (DOE) is the remediation of the 100 million gallons of high-level and low-level radioactive waste in the underground storage tanks at its Hanford, Savannah River, Oak Ridge, Idaho, and Fernald sites. Bench-scale batch tests have been conducted with sludge from the Melton Valley Storage Tank (MVST) Facility at Oak Ridge National Laboratory (ORNL) to evaluate separation processes for use in a comprehensive sludge-processing flow sheet for concentrating the radionuclides and reducing the volumes of storage tanks wastes for final disposal. This report discusses the hot cell apparatus, the characterization of the sludge, and the results obtained from a variety of basic and acidic leaching tests of samples of sludge. Approximately 5 L of sludge/supernate from MVST W-25 was retrieved and transferred to a stainless steel tank for mixing and storage in a hot cell. Samples were centrifuged to separate the sludge liquid and the sludge solids. Air-dried samples of sludge were analyzed to determine the concentrations of radionuclides, other metals, and anions. Based upon the air-dried weight, about 41% of the centrifuged, wet sludge solids was water. The major alpha-, gamma-, and beta-emitting radionuclides in the centrifuged, wet sludge solids were 137 Cs, 60 Co, 154 Eu, 241 Am, 244 Cm, 90 Sr, Pu, U, and Th. The other major metals (in addition to the U and Th) and the anions were Na, Ca, Al, K, Mg, NO 3 - , CO 3 2- , OH - , and O 2- . The organic carbon content was 3.0 ± 1.0%. The pH was 13

Selective Leaching of Chromium from Hanford Tank Sludge 241-U-108

International Nuclear Information System (INIS)

Rapko, Brian M.; Vienna, John D.

2002-01-01

This study evaluated the oxidants permanganate, MnO4-, and peroxynitrite, ONOO-, as selective chromium-leaching agents from washed 241-U-108 tank sludge under varying conditions of hydroxide concentration, temperature, and time. The mass changes and final sludge compositions were evaluated using glass-property models to ascertain the relative impacts of the various oxidative alkaline leach conditions on the amount of borosilicate glass required to immobilize a given amount of washed 241-U-108 Hanford tank sludge. Only permanganate leaching removes sufficient chromium to make the chromium concentration in the oxidatively alkaline leached solids non-limiting. In the absence of added oxidants, continued washing or caustic leaching have no beneficial effects. Peroxynitrite addition reduces the amount of glass required to immobilize a given amount of washed 241-U-108 tank sludge by approximately a factor of two. Depending on the leach conditions and the exact chromium concentration limits, contact with alkaline permanganate solutions reduces the amount of immobilized high-level waste glass by a factor of 10 to 30

Selective Leaching of Chromium from Hanford Tank Sludge 241-U-108

Energy Technology Data Exchange (ETDEWEB)

Rapko, Brian M.; Vienna, John D.

2002-09-09

This study evaluated the oxidants permanganate, MnO4-, and peroxynitrite, ONOO-, as selective chromium-leaching agents from washed 241-U-108 tank sludge under varying conditions of hydroxide concentration, temperature, and time. The mass changes and final sludge compositions were evaluated using glass-property models to ascertain the relative impacts of the various oxidative alkaline leach conditions on the amount of borosilicate glass required to immobilize a given amount of washed 241-U-108 Hanford tank sludge. Only permanganate leaching removes sufficient chromium to make the chromium concentration in the oxidatively alkaline leached solids non-limiting. In the absence of added oxidants, continued washing or caustic leaching have no beneficial effects. Peroxynitrite addition reduces the amount of glass required to immobilize a given amount of washed 241-U-108 tank sludge by approximately a factor of two. Depending on the leach conditions and the exact chromium concentration limits, contact with alkaline permanganate solutions reduces the amount of immobilized high-level waste glass by a factor of 10 to 30.

Hanford Tanks 241-C-203 and 241 C 204: Residual Waste Contaminant Release Model and Supporting Data

Energy Technology Data Exchange (ETDEWEB)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Schaef, Herbert T.

2007-05-23

This report was revised in May 2007 to correct 90Sr values in Chapter 3. The changes were made on page 3.9, paragraph two and Table 3.10; page 3.16, last paragraph on the page; and Tables 3.21 and 3.31. The rest of the text remains unchanged from the original report issued in October 2004. This report describes the development of release models for key contaminants that are present in residual sludge remaining after closure of Hanford Tanks 241-C-203 (C-203) and 241-C-204 (C-204). The release models were developed from data generated by laboratory characterization and testing of samples from these two tanks. Key results from this work are (1) future releases from the tanks of the primary contaminants of concern (99Tc and 238U) can be represented by relatively simple solubility relationships between infiltrating water and solid phases containing the contaminants; and (2) high percentages of technetium-99 in the sludges (20 wt% in C-203 and 75 wt% in C-204) are not readily water leachable, and, in fact, are very recalcitrant. This is similar to results found in related studies of sludges from Tank AY-102. These release models are being developed to support the tank closure risk assessments performed by CH2M HILL Hanford Group, Inc., for the U.S. Department of Energy.

Characterization and leaching study of sludge from Melton Valley Storage Tank W-25

Energy Technology Data Exchange (ETDEWEB)

Collins, J.L.; Egan, B.Z.; Beahm, E.C.; Chase, C.W.; Anderson, K.K.

1997-08-01

One of the greatest challenges facing the Department of Energy (DOE) is the remediation of the 100 million gallons of high-level and low-level radioactive waste in the underground storage tanks at its Hanford, Savannah River, Oak Ridge, Idaho, and Fernald sites. Bench-scale batch tests have been conducted with sludge from the Melton Valley Storage Tank (MVST) Facility at Oak Ridge National Laboratory (ORNL) to evaluate separation processes for use in a comprehensive sludge-processing flow sheet for concentrating the radionuclides and reducing the volumes of storage tanks wastes for final disposal. This report discusses the hot cell apparatus, the characterization of the sludge, and the results obtained from a variety of basic and acidic leaching tests of samples of sludge. Approximately 5 L of sludge/supernate from MVST W-25 was retrieved and transferred to a stainless steel tank for mixing and storage in a hot cell. Samples were centrifuged to separate the sludge liquid and the sludge solids. Air-dried samples of sludge were analyzed to determine the concentrations of radionuclides, other metals, and anions. Based upon the air-dried weight, about 41% of the centrifuged, wet sludge solids was water. The major alpha-, gamma-, and beta-emitting radionuclides in the centrifuged, wet sludge solids were {sup 137}Cs, {sup 60}Co, {sup 154}Eu, {sup 241}Am, {sup 244}Cm, {sup 90}Sr, Pu, U, and Th. The other major metals (in addition to the U and Th) and the anions were Na, Ca, Al, K, Mg, NO{sub 3}{sup {minus}}, CO{sub 3}{sup 2{minus}}, OH{sup {minus}}, and O{sub 2{minus}}. The organic carbon content was 3.0 {+-} 1.0%. The pH was 13.

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.

Decision analysis for mobilizing and retrieving sludge from double-shell tanks

International Nuclear Information System (INIS)

Brothers, A.J.; Williams, N.C.; Dukelow, J.S.; Hansen, R.I.

1997-09-01

This decision analysis evaluates alternative technologies for the initial mobilization and retrieval of sludges in double-shell tanks (DSTs). The analysis is from the perspective of the need to move sludges from one DST to another for interim retrieval. It supports the more general decision of which technologies to use to retreive various types of DST waste. The initial analysis is from the perspective of a typical DST with 2 ft of sludge to mobilize. During the course of the analysis, it became clear that it was important to also consider sludge mobilization in support of the high-level waste (HLW) vitrification demonstration plant, and in particular the risks associated with failing to meeting the minimum order requirements for the vendor, as well as the cost of mobilization and retrieval from the HLW vitrification source tanks

Assessment of alternative management techniques of tank bottom petroleum sludge in Oman

International Nuclear Information System (INIS)

Al-Futaisi, Ahmed; Jamrah, Ahmad; Yaghi, Basma; Taha, Ramzi

2007-01-01

This paper investigated several options for environmentally acceptable management techniques of tank bottom oily sludge. In particular, we tested the applicability of managing the sludge by three options: (1) as a fuel supplement; (2) in solidification; (3) as a road material. Environmental testing included determination of heavy metals concentration; toxic organics concentration and radiological properties. The assessment of tank bottom sludge as a fuel supplement included various properties such as proximate analysis, ultimate analysis and energy content. Solidified sludge mixtures and road application sludge mixtures were subjected to leaching using the toxicity characteristic leaching procedure (TCLP). Tank bottom sludge was characterized as having higher concentrations of lead, zinc, and mercury, but lower concentrations of nickel, copper and chromium in comparison with values reported in the literature. Natural occurring radioactive minerals (NORM) activity values obtained on different sludge samples were very low or negligible compared to a NORM standard value of 100 Bq/g. The fuel assessment results indicate that the heating values, the carbon content and the ash content of the sludge samples are comparable with bituminous coal, sewage sludge, meat and bone meal and petroleum coke/coal mixture, but lower than those in car tyres and petroleum coke. The nitrogen content is lower than those fuels mentioned above, while the sulfur content seems comparable with bituminous coal, petroleum coke and a petroleum coke/coal mixture. The apparent lack of leachability of metals from solidification and road material sludge applications suggests that toxic metals and organics introduced to these applications are not readily attacked by weak acid solutions and would not be expected to migrate or dissolved into the water. Thus, in-terms of trace metals and organics, the suggested sludge applications would not be considered hazardous as defined by the TCLP leaching procedure

Hydrothermal processing of inorganic components of Hanford tank sludge

International Nuclear Information System (INIS)

Oldenborg, R.; Buelow, S.J.; Dyer, R.B.; Anderson, G.; Dell'Orco, P.C.; Funk, K.; Wilmanns, E.; Knutsen, K.

1994-09-01

Hydrothermal Processing (HTP) is an attractive approach for the treatment of Hanford tank sludge. Hydrothermal Processing refers to a waste treatment technique in which an aqueous waste stream is fed through a chemical reactor at elevated temperatures and pressures to effect desired chemical transformations and separations. Transformations such as organic and nitrate destruction and sludge reformulation have been demonstrated at pilot scale using simulants of Hanford tank wastes. At sufficiently high temperatures and pressures organics and nitrates are destroyed in seconds, producing primarily simple products such as CO 3 2- , H 2 O, N 2 , N 2 O and OH - , and sludges are reduced in volume and reformulated as rapid settling oxides amenable to downstream separation, or in some cases reformulated as soluble products. This report describes the hydrothermal dissolution of chromium and chromium oxide; the hydrothermal oxidation of chromium with nitrate; hydrothermal dissolution of aluminum-bearing sludges; the solubility of aluminum compounds in caustic hydrothermal media; experimental techniques for the study of solubility and phase behavior; optical cell studies of basic aluminate solution solubilities; and high temperature, low density salt solubility in the packed-bed flow apparatus

SLUDGE PARTICLE SEPAPATION EFFICIENCIES DURING SETTLER TANK RETRIEVAL INTO SCS-CON-230

Energy Technology Data Exchange (ETDEWEB)

DEARING JI; EPSTEIN M; PLYS MG

2009-07-16

The purpose of this document is to release, into the Hanford Document Control System, FA1/0991, Sludge Particle Separation Efficiencies for the Rectangular SCS-CON-230 Container, by M. Epstein and M. G. Plys, Fauske & Associates, LLC, June 2009. The Sludge Treatment Project (STP) will retrieve sludge from the 105-K West Integrated Water Treatment System (IWTS) Settler Tanks and transfer it to container SCS-CON-230 using the Settler Tank Retrieval System (STRS). The sludge will enter the container through two distributors. The container will have a filtration system that is designed to minimize the overflow of sludge fines from the container to the basin. FAI/09-91 was performed to quantify the effect of the STRS on sludge distribution inside of and overflow out of SCS-CON-230. Selected results of the analysis and a system description are discussed. The principal result of the analysis is that the STRS filtration system reduces the overflow of sludge from SCS-CON-230 to the basin by roughly a factor of 10. Some turbidity can be expected in the center bay where the container is located. The exact amount of overflow and subsequent turbidity is dependent on the density of the sludge (which will vary with location in the Settler Tanks) and the thermal gradient between the SCS-CON-230 and the basin. Attachment A presents the full analytical results. These results are applicable specifically to SCS-CON-230 and the STRS filtration system's expected operating duty cycles.

Field study comparing the effect of hydraulic mixing on septic tank performance and sludge accumulation.

Science.gov (United States)

Almomani, Fares

2016-01-01

This study investigates the effect of hydraulic mixing on anaerobic digestion and sludge accumulation in a septic tank. The performance of a septic tank equipped with a hydraulic mixer was compared with that of a similar standard septic tank over a period of 10 months. The study was conducted in two phases: Phase-I--from May to November 2013 (6 months); Phase-II--from January to May 2014 (4 months). Hydraulic mixing effectively reduced the effluent biological oxygen demand (BOD) and total suspended solids, and reduced the sludge accumulation rate in the septic tank. The BOD removal efficiencies during Phase-II were 65% and 75% in the standard septic tank and a septic tank equipped with hydraulic mixer (Smart Digester™), respectively. The effect of hydraulic mixing reduced the rate of sludge accumulation from 0.64 cm/day to 0.27 cm/day, and increased the pump-out interval by a factor of 3.

STATUS OF MECHANICAL SLUDGE REMOVAL AND COOLING COILS CLOSURE AT THE SAVANNAH RIVER SITE - F TANK FARM CLOSURE PORJECT -9225

International Nuclear Information System (INIS)

Jolly, R.

2009-01-01

The Savannah River Site F-Tank Farm Closure project has successfully performed Mechanical Sludge Removal using the Waste on Wheels (WOW) system within two of its storage tanks. The Waste on Wheels (WOW) system is designed to be relatively mobile with the ability for many components to be redeployed to multiple tanks. It is primarily comprised of Submersible Mixer Pumps (SMPs), Submersible Transfer Pumps (STPs), and a mobile control room with a control panel and variable speed drives. These tanks, designated as Tank 6 and Tank 5 respectively, are Type I waste tanks located in F-Tank Farm (FTF) with a capacity of 2839 cubic meters (750,000 gallons) each. In addition, Type I tanks have 34 vertically oriented cooling coils and two horizontal cooling coil circuits along the tank floor. DOE intends to remove from service and operationally close Tank 5 and Tank 6 and other HLW tanks that do not meet current containment standards. After obtaining regulatory approval, the tanks and cooling coils will be isolated and filled with grout for long term stabilization. Mechanical Sludge Removal of the remaining sludge waste within Tank 6 removed ∼ 75% of the original 25,000 gallons in August 2007. Utilizing lessons learned from Tank 6, Tank 5 Mechanical Sludge Removal completed removal of ∼ 90% of the original 125 cubic meters (33,000 gallons) of sludge material in May 2008. The successful removal of sludge material meets the requirement of approximately 19 to 28 cubic meters (5,000 to 7,500 gallons) remaining prior to the Chemical Cleaning process. The Chemical Cleaning Process will utilize 8 wt% oxalic acid to dissolve the remaining sludge heel. The flow sheet for Chemical Cleaning planned a 20:1 volume ratio of acid to sludge for the first strike with mixing provided by the submersible mixer pumps. The subsequent strikes will utilize a 13:1 volume ratio of acid to sludge with no mixing. The results of the Chemical Cleaning Process are detailed in the 'Status of Chemical

STATUS OF MECHANICAL SLUDGE REMOVAL AND COOLING COILS CLOSURE AT THE SAVANNAH RIVER SITE - F TANK FARM CLOSURE PROJECT - 9225

Energy Technology Data Exchange (ETDEWEB)

Jolly, R

2009-01-06

The Savannah River Site F-Tank Farm Closure project has successfully performed Mechanical Sludge Removal using the Waste on Wheels (WOW) system within two of its storage tanks. The Waste on Wheels (WOW) system is designed to be relatively mobile with the ability for many components to be redeployed to multiple tanks. It is primarily comprised of Submersible Mixer Pumps (SMPs), Submersible Transfer Pumps (STPs), and a mobile control room with a control panel and variable speed drives. These tanks, designated as Tank 6 and Tank 5 respectively, are Type I waste tanks located in F-Tank Farm (FTF) with a capacity of 2839 cubic meters (750,000 gallons) each. In addition, Type I tanks have 34 vertically oriented cooling coils and two horizontal cooling coil circuits along the tank floor. DOE intends to remove from service and operationally close Tank 5 and Tank 6 and other HLW tanks that do not meet current containment standards. After obtaining regulatory approval, the tanks and cooling coils will be isolated and filled with grout for long term stabilization. Mechanical Sludge Removal of the remaining sludge waste within Tank 6 removed {approx} 75% of the original 25,000 gallons in August 2007. Utilizing lessons learned from Tank 6, Tank 5 Mechanical Sludge Removal completed removal of {approx} 90% of the original 125 cubic meters (33,000 gallons) of sludge material in May 2008. The successful removal of sludge material meets the requirement of approximately 19 to 28 cubic meters (5,000 to 7,500 gallons) remaining prior to the Chemical Cleaning process. The Chemical Cleaning Process will utilize 8 wt% oxalic acid to dissolve the remaining sludge heel. The flow sheet for Chemical Cleaning planned a 20:1 volume ratio of acid to sludge for the first strike with mixing provided by the submersible mixer pumps. The subsequent strikes will utilize a 13:1 volume ratio of acid to sludge with no mixing. The results of the Chemical Cleaning Process are detailed in the &apos

DETERMINATION OF THE FRACTION OF GIBBSITE AND BOEHMITE FORMS OF ALUMINUM IN TANK 51H SLUDGE

International Nuclear Information System (INIS)

Hay, M; Kofi Adu-Wusu, K; Daniel McCabe, D

2008-01-01

The Savannah River National Laboratory (SRNL) was tasked with developing a test to determine the fraction of the gibbsite and boehmite forms of aluminum in the sludge solids. Knowledge of the fractions of gibbsite and boehmite in the sludge contained in various waste tanks would facilitate better sludge mass reduction estimates and allow better planning/scheduling for sludge batch preparation. The composite sludge sample prepared for use in the test from several small samples remaining from the original 3-L sample appears to be representative of the original sample based on the characterization data. A Gibbsite/Boehmite Test was developed that uses 8 M NaOH and a temperature of 65 C to dissolve aluminum. The soluble aluminum concentration data collected during the test indicates that, for the three standards containing gibbsite, all of the gibbsite dissolved in approximately 2 hours. Under the test conditions boehmite dissolved at more than an order of magnitude more slowly than gibbsite. An estimate based on the soluble aluminum concentration from the sludge sample at two hours into the test indicates the sludge solids contain a form of aluminum that dissolves at a rate similar to the 100% Boehmite standard. Combined with the XRD data from the original 3-L sample, these results provide substantial evidence that the boehmite form of aluminum predominates in the sludge. A calculation from the results of the Gibbsite/Boehmite test indicates the sludge contains ∼3% gibbsite and ∼97% boehmite. The sludge waste in Tank 51H was recently treated under Low Temperature Aluminum Dissolution (LTAD) conditions and a substantial fraction of aluminum (i.e., sludge mass) was removed, avoiding production of over 100 glass canisters in Defense Waste Processing Facility (DWPF). Results of the Gibbsite/Boehmite test indicate that the aluminum in this sludge was in the form of the more difficult to dissolve boehmite form of aluminum. Since boehmite may be the dominant form of

CHEMICAL SLUDGE HEEL REMOVAL AT THE SAVANNAH RIVER SITE F TANK FARM CLOSURE PROJECT 8183

International Nuclear Information System (INIS)

Thaxton, D; Timothy Baughman, T

2008-01-01

Chemical Sludge Removal (CSR) is the final waste removal activity planned for some of the oldest nuclear waste tanks located at the Savannah River Site (SRS) in Aiken, SC. In 2008, CSR will be used to empty two of these waste tanks in preparation for final closure. The two waste tanks chosen to undergo this process have previously leaked small amounts of nuclear waste from the primary tank into an underground secondary containment pan. CSR involves adding aqueous oxalic acid to the waste tank in order to dissolve the remaining sludge heel. The resultant acidic waste solution is then pumped to another waste tank where it will be neutralized and then stored awaiting further processing. The waste tanks to be cleaned have a storage capacity of 2.84E+06 liters (750,000 gallons) and a target sludge heel volume of 1.89E+04 liters (5,000 gallons) or less for the initiation of CSR. The purpose of this paper is to describe the CSR process and to discuss the most significant technical issues associated with the development of CSR

Technology study of Gunite tank sludge mobilization at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Energy Technology Data Exchange (ETDEWEB)

DeVore, J.R.; Herrick, T.J.; Lott, K.E.

1994-12-01

The Oak Ridge National Laboratory (ORNL) Gunite Tank Sludge Mobilization Technology Study was initiated to support the Gunite Tank Treatability Study effort. The technology study surveyed the methods and technologies available for tank cleaning and sludge mobilization in a radioactive environment. Technologies were identified and considered for applicability to the Gunite and Associated Tanks (GAAT) problems. These were then either accepted for further study or rejected as not applicable. Technologies deemed applicable to the GAAT sludge removal project were grouped for evaluation according to (1) deployment method, (2) types of remotely operated end effector equipment applicable to removal of sludge, (3) methods for removing wastes from the tanks, and (4) methods for concrete removal. There were three major groups of deployment technologies: ``past practice`` technologies, mechanical arm-based technologies, and vehicle-based technologies. The different technologies were then combined into logical sequences of deployment platform, problem, end effector, conveyance, post-removal treatment required (if any), and disposition of the waste. Many waste removal options are available, but the best technology in one set of circumstances at one site might not be the best type to use at a different site. No single technology is capable of treating the entire spectrum of wastes that will be encountered in GAAT. None of the systems used in other industries appears to be suitable, primarily because of the nature of the sludges in the GAAT Operable Unit (OU), their radiation levels, and tank geometries. Other commercial technologies were investigated but rejected because the authors did not believe them to be applicable.

Technology study of Gunite tank sludge mobilization at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

DeVore, J.R.; Herrick, T.J.; Lott, K.E.

1994-12-01

The Oak Ridge National Laboratory (ORNL) Gunite Tank Sludge Mobilization Technology Study was initiated to support the Gunite Tank Treatability Study effort. The technology study surveyed the methods and technologies available for tank cleaning and sludge mobilization in a radioactive environment. Technologies were identified and considered for applicability to the Gunite and Associated Tanks (GAAT) problems. These were then either accepted for further study or rejected as not applicable. Technologies deemed applicable to the GAAT sludge removal project were grouped for evaluation according to (1) deployment method, (2) types of remotely operated end effector equipment applicable to removal of sludge, (3) methods for removing wastes from the tanks, and (4) methods for concrete removal. There were three major groups of deployment technologies: ''past practice'' technologies, mechanical arm-based technologies, and vehicle-based technologies. The different technologies were then combined into logical sequences of deployment platform, problem, end effector, conveyance, post-removal treatment required (if any), and disposition of the waste. Many waste removal options are available, but the best technology in one set of circumstances at one site might not be the best type to use at a different site. No single technology is capable of treating the entire spectrum of wastes that will be encountered in GAAT. None of the systems used in other industries appears to be suitable, primarily because of the nature of the sludges in the GAAT Operable Unit (OU), their radiation levels, and tank geometries. Other commercial technologies were investigated but rejected because the authors did not believe them to be applicable

Tank 12H residuals sample analysis report

Energy Technology Data Exchange (ETDEWEB)

Oji, L. N. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Shine, E. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Diprete, D. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coleman, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hay, M. S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-06-11

The Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (SRR) to provide sample preparation and analysis of the Tank 12H final characterization samples to determine the residual tank inventory prior to grouting. Eleven Tank 12H floor and mound residual material samples and three cooling coil scrape samples were collected and delivered to SRNL between May and August of 2014.

SAVANNAH RIVER SITE INCIPIENT SLUDGE MIXING IN RADIOACTIVE LIQUID WASTE STORAGE TANKS DURING SALT SOLUTION BLENDING

Energy Technology Data Exchange (ETDEWEB)

Leishear, R.; Poirier, M.; Lee, S.; Steeper, T.; Fowley, M.; Parkinson, K.

2011-01-12

This paper is the second in a series of four publications to document ongoing pilot scale testing and computational fluid dynamics (CFD) modeling of mixing processes in 85 foot diameter, 1.3 million gallon, radioactive liquid waste, storage tanks at Savannah River Site (SRS). Homogeneous blending of salt solutions is required in waste tanks. Settled solids (i.e., sludge) are required to remain undisturbed on the bottom of waste tanks during blending. Suspension of sludge during blending may potentially release radiolytically generated hydrogen trapped in the sludge, which is a safety concern. The first paper (Leishear, et. al. [1]) presented pilot scale blending experiments of miscible fluids to provide initial design requirements for a full scale blending pump. Scaling techniques for an 8 foot diameter pilot scale tank were also justified in that work. This second paper describes the overall reasons to perform tests, and documents pilot scale experiments performed to investigate disturbance of sludge, using non-radioactive sludge simulants. A third paper will document pilot scale CFD modeling for comparison to experimental pilot scale test results for both blending tests and sludge disturbance tests. That paper will also describe full scale CFD results. The final paper will document additional blending test results for stratified layers in salt solutions, scale up techniques, final full scale pump design recommendations, and operational recommendations. Specifically, this paper documents a series of pilot scale tests, where sludge simulant disturbance due to a blending pump or transfer pump are investigated. A principle design requirement for a blending pump is UoD, where Uo is the pump discharge nozzle velocity, and D is the nozzle diameter. Pilot scale test results showed that sludge was undisturbed below UoD = 0.47 ft{sup 2}/s, and that below UoD = 0.58 ft{sup 2}/s minimal sludge disturbance was observed. If sludge is minimally disturbed, hydrogen will not be

Characteristics of residues from thermally treated anaerobic sludges

International Nuclear Information System (INIS)

Friedman, A.A.; Smith, J.E.; De Santis, J.; Ptak, T.; Ganley, R.C.

1988-01-01

Sludge management and disposal are probably the most difficult and expensive operations involved in wastewater treatment today. To minimize final disposal costs many waste treatment facilities practice some form of anaerobic digestion and dewatering to reduce the volume and offensiveness of their by-product sludges. One potential alternative for reducing sludge volumes consists of high temperature, partial oxidation of these previously digested sludges (PDS) and subsequent anaerobic biological conversion of resulting soluble organics to methane. This paper describes solids destruction, residue characteristics and biodegradability factors that should be considered in the design of liquid thermal treatment processes for the management of anaerobic sludges. To date only very limited information is available concerning the suitability of thermally treated PDS to serve as a substrate for the generation of methane. The primary objective of this research was to determine the feasibility of producing methane efficiently from the residual VSS in anaerobically digested sludges. Secondary goals were to establish the ''best'' conditions for thermal treatment for solubilizing PDS, to observe the effect of the soluble products on methanogenesis and to evaluate process sidestreams for dewaterability and anaerobic biodegradability

Caustic leaching of composite AZ-101/AZ-102 Hanford tank sludge

International Nuclear Information System (INIS)

Rapko, B.M.; Wagner, M.J.

1997-07-01

To reduce the quantity (and hence the cost) of glass canisters needed for disposing of high-level radioactive wastes from the Hanford tank farms, pretreatment processes are needed to remove as much nonradioactive material as possible. This report describes the results of a laboratory-scale caustic leaching test performed on a composite derived from a combination of 241-AZ-101 and 241-AZ-102 Hanford Tank sludges. The goals of this FY 1996 test were to evaluate the effectiveness of caustic leaching on removing key components from the sludge and to evaluate the effectiveness of varying the free-hydroxide concentrations by incrementally increasing the free hydroxide concentration of the leach steps up to 3 M free hydroxide. Particle-size analysis of the treated and untreated sludge indicated that the size and range of the sludge particles remained essentially unchanged by the caustic leaching treatment. Both before and after caustic leaching, a particle range of 0.2 microm to 50 microm was observed, with mean particle diameters of 8.5 to 9 microm based on the volume distribution and mean particle diameters of 0.3 to 0.4 microm based on the number distribution

Treatment aerobic conjugate of sludges of septic tanks and household organic solid wastes

Directory of Open Access Journals (Sweden)

Wanderson Barbosa da Silva Feitosa

2009-12-01

Full Text Available It was aimed at to evaluate the co-composting as technological alternative to the treatment of sludges of septic tanks with household organic solid wastes originating from cities of small and medium loads. The sludges and the domiciliary organic solid waste were collected in Cabaceiras, Caraúbas and Queimadas, state of Paraíba. The experiment consisted of four treatments with three repetitions, totaling 12 reactors, of cylindrical configuration in polyethylene of 100 L of capacity. Each reactor was fed with 50 kg substratum with variable composition in function of the sludge fraction: 0%, 10%, 20% and 30%. The manual turning was accomplished three times a week and the temperature was monitored daily. The total destruction of helminth eggs in period differentiated in function of the sludges fraction (14, 28, 35 and 63 days and the medium transformation of 54.1% of sludges in biosolids class A and class B, with favorable characteristics to the use in agricultural cultures in 91 days, expressed the viability of the treatment for co-composting of sludges of tanks septic multichamber of collective use for the cities of small and medium load.

Colloidal agglomerates in tank sludge: Impact on waste processing

International Nuclear Information System (INIS)

Bunker, B.C.; Martin, J.E.

1998-01-01

'Insoluble colloidal sludges in hazardous waste streams such as tank wastes can pose serious problems for waste processing, interfering with retrieval, transport, separation, and solidification procedures. Properties of sediment layers and sludge suspensions such as slurry viscosities, sedimentation rates, and final sediment densities can vary by orders of magnitude depending on the particle types present, the degree to which the particles agglomerate or stick to each other, and on a wide range of processing parameters such as solution shear rates, pH, salt content, and temperature. The objectives of this work are to: (1) understand the factors controlling the nature and extent of colloidal agglomeration under expected waste processing conditions; (2) determine how agglomeration phenomena influence physical properties relevant to waste processing including rheology, sedimentation, and filtration; and (3) develop strategies for optimizing processing conditions via control of agglomeration phenomena. Insoluble colloidal sludges in hazardous waste streams such as tank wastes can pose serious problems for waste processing, interfering with retrieval, transport, separation, and solidification procedures. Properties of sediment layers and sludge suspensions such as slurry viscosities, sedimentation rates, and final sediment densities can vary by orders of magnitude depending on the particle types present, the degree to which the particles agglomerate or stick to each other, and on a wide range of processing parameters such as solution shear rates, pH, salt content, and temperature. The objectives of this work are to: (1) understand the factors controlling the nature and extent of colloidal agglomeration under expected waste processing conditions; (2) determine how agglomeration phenomena influence physical properties relevant to waste processing including rheology, sedimentation, and filtration; and (3) develop strategies for optimizing processing conditions via control

Characterization of the tank 51 alternate reductant sludge batch 9 slurry sample (HTF-51-15-130)

Energy Technology Data Exchange (ETDEWEB)

Reboul, S. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-02-01

Tank 51 slurry sample HTF-51-15-130 was collected following sludge washing at the Tank Farm. The sample was received at SRNL and then characterized in preparation for qualification of the alternate reductant Sludge Batch 9 (SB9) flowsheet. In this characterization, densities, solids distribution, elemental constituents, anionic constituents, carbon content, and select radioisotopes were quantified.

Grout performance in support of in situ grouting of the TH4 tank sludge

Energy Technology Data Exchange (ETDEWEB)

Hunt, R.D.; Kauschinger, J.L.; Spence, R.D.

1999-04-01

The cold demonstration test proved that less water was required to pump the in situ grout formulation than had been previously tested in the laboratory. The previous in situ grout formulation was restandardized with the same relative amounts of dry blend ingredients, albeit adding a fluidized admixture, but specifying less water for the slurry mix that must by pumped through the nozzles at high pressure. Also, the target GAAT tank for demonstrating this is situ grouting technique has been shifted to Tank TH4. A chemical surrogate sludge for TH4 was developed and tested in the laboratory, meeting expectations for leach resistance and strenght at 35 wt % sludge loading. It addition, a sample of hot TH4 sludge was also tested at 35 wt % sludge loading and proved to have superior strength and leach resistance compared with the surrogate test.

Demonstration of the Defense Waste Processing Facility vitrification process for Tank 42 radioactive sludge -- Glass preparation and characterization

International Nuclear Information System (INIS)

Bibler, N.E.; Fellinger, T.L.; Marshall, K.M.; Crawford, C.L.; Cozzi, A.D.; Edwards, T.B.

1999-01-01

The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) is currently processing and immobilizing the radioactive high level waste sludge at SRS into a durable borosilicate glass for final geological disposal. The DWPF has recently finished processing the first radioactive sludge batch, and is ready for the second batch of radioactive sludge. The second batch is primarily sludge from Tank 42. Before processing this batch in the DWPF, the DWPF process flowsheet has to be demonstrated with a sample of Tank 42 sludge to ensure that an acceptable melter feed and glass can be made. This demonstration was recently completed in the Shielded Cells Facility at SRS. An earlier paper in these proceedings described the sludge composition and processes necessary for producing an acceptable melter fee. This paper describes the preparation and characterization of the glass from that demonstration. Results substantiate that Tank 42 sludge after mixing with the proper amount of glass forming frit (Frit 200) can be processed to make an acceptable glass

Characterization Of Actinides In Simulated Alkaline Tank Waste Sludges And Leachates

International Nuclear Information System (INIS)

Nash, Kenneth L.

2008-01-01

In this project, both the fundamental chemistry of actinides in alkaline solutions (relevant to those present in Hanford-style waste storage tanks), and their dissolution from sludge simulants (and interactions with supernatants) have been investigated under representative sludge leaching procedures. The leaching protocols were designed to go beyond conventional alkaline sludge leaching limits, including the application of acidic leachants, oxidants and complexing agents. The simulant leaching studies confirm in most cases the basic premise that actinides will remain in the sludge during leaching with 2-3 M NaOH caustic leach solutions. However, they also confirm significant chances for increased mobility of actinides under oxidative leaching conditions. Thermodynamic data generated improves the general level of experiemental information available to predict actinide speciation in leach solutions. Additional information indicates that improved Al removal can be achieved with even dilute acid leaching and that acidic Al(NO3)3 solutions can be decontaminated of co-mobilized actinides using conventional separations methods. Both complexing agents and acidic leaching solutions have significant potential to improve the effectiveness of conventional alkaline leaching protocols. The prime objective of this program was to provide adequate insight into actinide behavior under these conditions to enable prudent decision making as tank waste treatment protocols develop.

CHARACTERIZATION OF ACTINIDES IN SIMULATED ALKALINE TANK WASTE SLUDGES AND LEACHATES

Energy Technology Data Exchange (ETDEWEB)

Nash, Kenneth L.

2008-11-20

In this project, both the fundamental chemistry of actinides in alkaline solutions (relevant to those present in Hanford-style waste storage tanks), and their dissolution from sludge simulants (and interactions with supernatants) have been investigated under representative sludge leaching procedures. The leaching protocols were designed to go beyond conventional alkaline sludge leaching limits, including the application of acidic leachants, oxidants and complexing agents. The simulant leaching studies confirm in most cases the basic premise that actinides will remain in the sludge during leaching with 2-3 M NaOH caustic leach solutions. However, they also confirm significant chances for increased mobility of actinides under oxidative leaching conditions. Thermodynamic data generated improves the general level of experiemental information available to predict actinide speciation in leach solutions. Additional information indicates that improved Al removal can be achieved with even dilute acid leaching and that acidic Al(NO3)3 solutions can be decontaminated of co-mobilized actinides using conventional separations methods. Both complexing agents and acidic leaching solutions have significant potential to improve the effectiveness of conventional alkaline leaching protocols. The prime objective of this program was to provide adequate insight into actinide behavior under these conditions to enable prudent decision making as tank waste treatment protocols develop.

Hanford Tanks 241-AY-102 and 241-BX-101: Sludge Composition and Contaminant Release Data

International Nuclear Information System (INIS)

Krupka, Kenneth M.; Deutsch, William J.; Lindberg, Michael J.; Cantrell, Kirk J.; Hess, Nancy J.; Schaef, Herbert T.; Arey, Bruce W.

2004-01-01

This report describes the results of testing sludge samples from Hanford tanks 241-AY-102 (AY-102) and 241-BX-101 (BX-101). These tests were conducted to characterize the sludge and assess the water leachability of contaminants from the solids. This work is being conducted to support the tank closure risk assessments being performed by CH2M HILL Hanford Group, Inc. for the U.S. Department of Energy. This is the first report of testing of BX-101 sludge and the second report of testing of AY-102. Lindberg and Deutsch (2003) described the first phase of testing on AY-102 material

Characterization of Settler Tank and KW Container Sludge Simulants

Energy Technology Data Exchange (ETDEWEB)

Burns, Carolyn A.; Luna, Maria; Schmidt, Andrew J.

2009-05-12

The Sludge Treatment Project (STP), managed by CH2M Hill Plateau Remediation Company (CHPRC) has specified base formulations for non-radioactive sludge simulants for use in the development and testing of equipment for sludge sampling, retrieval, transport, and processing. In general, the simulant formulations are based on the average or design-basis physical and chemical properties obtained by characterizing sludge samples. The simulants include surrogates for uranium metal, uranium oxides (agglomerates and fine particulate), and the predominant chemical phases (iron and aluminum hydroxides, sand). Specific surrogate components were selected to match the nominal particle-size distribution and particle-density data obtained from sludge sample analysis. Under contract to CHPRC, Pacific Northwest National Laboratory (PNNL) has performed physical and rheological characterization of simulants, and the results are reported here. Two base simulant types (dry) were prepared by STP staff at the Maintenance and Storage Facility and received by PNNL on February 12, 2009: Settler Tank Simulant and KW Container Sludge Simulant. The objectives of this simulant characterization effort were to provide baseline characterization data on simulants being used by STP for process development and equipment testing and provide a high-level comparison of the simulant characteristics to the targets used to formulate the simulants.

Dynamic modeling of sludge compaction and consolidation processes in wastewater secondary settling tanks.

Science.gov (United States)

Abusam, A; Keesman, K J

2009-01-01

The double exponential settling model is the widely accepted model for wastewater secondary settling tanks. However, this model does not estimate accurately solids concentrations in the settler underflow stream, mainly because sludge compression and consolidation processes are not considered. In activated sludge systems, accurate estimation of the solids in the underflow stream will facilitate the calibration process and can lead to correct estimates of particularly kinetic parameters related to biomass growth. Using principles of compaction and consolidation, as in soil mechanics, a dynamic model of the sludge consolidation processes taking place in the secondary settling tanks is developed and incorporated to the commonly used double exponential settling model. The modified double exponential model is calibrated and validated using data obtained from a full-scale wastewater treatment plant. Good agreement between predicted and measured data confirmed the validity of the modified model.

Grout and vitrification formula development for immobilization of hazardous radioactive tank sludges at ORNL

International Nuclear Information System (INIS)

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

1997-01-01

Stabilization/solidification (S/S) has been identified as the preferred treatment option for hazardous radioactive sludges, and currently grouting and vitrification are considered the leading candidate S/S technologies. Consequently, a project was initiated at Oak Ridge National Laboratory (ORNL) to define composition envelopes, or operating windows, for acceptable grout and glass formulations containing Melton Valley Storage Tank (MVST) sludges. The resulting data are intended to be used as guidance for the eventual treatment of the MVST sludges by the government and/or private sector. Wastewater at ORNL is collected, evaporated, and stored in the MVSTs pending treatment for disposal. The waste separates into two phases: sludge and supernate. The sludges in the tank bottoms have been accumulating for several years and contain a high amount of radioactivity, with some classified as transuranic (TRU) sludges. The available total constituent analysis for the MVST sludge indicates that the Resource and Conservation Recovery Act (RCRA) metal concentrations are high enough to be potentially RCRA hazardous; therefore, these sludges have the potential to be designated as mixed TRU waste. S/S treatment must be performed to remove free liquids and reduce the leach rate of RCRA metals. This paper focuses on initial results for the development of the operating window for vitrification. However, sufficient data on grouting are presented to allow a comparison of the two options

Grout and vitrification formula development for immobilization of hazardous radioactive tank sludges at ORNL

Energy Technology Data Exchange (ETDEWEB)

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

1997-12-31

Stabilization/solidification (S/S) has been identified as the preferred treatment option for hazardous radioactive sludges, and currently grouting and vitrification are considered the leading candidate S/S technologies. Consequently, a project was initiated at Oak Ridge National Laboratory (ORNL) to define composition envelopes, or operating windows, for acceptable grout and glass formulations containing Melton Valley Storage Tank (MVST) sludges. The resulting data are intended to be used as guidance for the eventual treatment of the MVST sludges by the government and/or private sector. Wastewater at ORNL is collected, evaporated, and stored in the MVSTs pending treatment for disposal. The waste separates into two phases: sludge and supernate. The sludges in the tank bottoms have been accumulating for several years and contain a high amount of radioactivity, with some classified as transuranic (TRU) sludges. The available total constituent analysis for the MVST sludge indicates that the Resource and Conservation Recovery Act (RCRA) metal concentrations are high enough to be potentially RCRA hazardous; therefore, these sludges have the potential to be designated as mixed TRU waste. S/S treatment must be performed to remove free liquids and reduce the leach rate of RCRA metals. This paper focuses on initial results for the development of the operating window for vitrification. However, sufficient data on grouting are presented to allow a comparison of the two options.

Development of an in situ method to define the rheological properties of slurries and sludges stored in underground tanks

International Nuclear Information System (INIS)

Heath, W.O.

1987-04-01

A method for measuring the in situ flow properties of high-level radioactive waste (HLW) sludges has been developed at Pacific Northwest Laboratory, along with a preconceptual design for a shear vane device that can be installed in underground HLW storage tanks and used to make those measurements remotely. The data obtained with this device will assist in the design of mixing equipment used to resuspend and remove HLW sludges from their storage tanks for downstream processing. This method is also suitable for remotely characterizing other types of waste sludges and slurries. Commonly available viscometric methods were adapted to allow characterization of sludge samples in the laboratory such that the laboratory and in-tank data can be directly compared (scaled up). Procedures for conducting measurements and analyzing the results in terms of useful mathematical models describing both start-up and steady-state flow behavior are presented, as is a brief tutorial on the types of flow behavior that can be exhibited by tank sludges. 30 refs., 36 figs., 14 tabs

Stabilization of In-Tank Residual Wastes and External-Tank Soil Contamination for the Hanford Tank Closure Program: Applications to the AX Tank Farm

Energy Technology Data Exchange (ETDEWEB)

Anderson, H.L.; Dwyer, B.P.; Ho, C.; Krumhansl, J.L.; McKeen, G.; Molecke, M.A.; Westrich, H.R.; Zhang, P.

1998-11-01

Technical support for the Hanford Tank Closure Program focused on evaluation of concepts for immobilization of residual contaminants in the Hanford AX tanks and underlying soils, and identification of cost-effective approaches to improve long-term performance of AX tank farm cIosure systems. Project objectives are to develop materials or engineered systems that would significantly reduce the radionuclide transport to the groundwater from AX tanks containing residual waste. We pursued several studies that, if implemented, would help achieve these goals. They include: (1) tank fill design to reduce water inilltration and potential interaction with residual waste; (2) development of in-tank getter materials that would specifically sorb or sequester radionuclides; (3) evaluation of grout emplacement under and around the tanks to prevent waste leakage during waste retrieval or to minimize water infiltration beneath the tanks; (4) development of getters that will chemically fix specific radionuclides in soils under tanks; and (5) geochemical and hydrologic modeling of waste-water-soil-grout interactions. These studies differ in scope from the reducing grout tank fill employed at the Savannah River Site in that our strategy improves upon tank fill design by providing redundancy in the barriers to radionuclide migration and by modification the hydrogeochemistry external to the tanks.

Fabrication of a Sludge-Conditioning System for processing legacy wastes from the Gunite and Associated Tanks

International Nuclear Information System (INIS)

Randolph, J.D.; Lewis, B.E.; Farmer, J.R.; Johnson, M.A.

2000-01-01

The Sludge Conditioning System (SCS) for the Gunite and Associated Tanks (GAATs) is designed to receive, monitor, characterize and process legacy waste materials from the South Tank Farm tanks in preparation for final transfer of the wastes to the Melton Valley Storage Tanks (MVSTs), which are located at Oak Ridge National Laboratory. The SCS includes (1) a Primary Conditioning System (PCS) Enclosure for sampling and particle size classification, (2) a Solids Monitoring Test Loop (SMTL) for slurry characterization, (3) a Waste Transfer Pump to retrieve and transfer waste materials from GAAT consolidation tank W-9 to the MVSTs, (4) a PulsAir Mixing System to provide mixing of consolidated sludges for ease of retrieval, and (5) the interconnecting piping and valving. This report presents the design, fabrication, cost, and fabrication schedule information for the SCS

Solidification process for sludge residue

International Nuclear Information System (INIS)

Pearce, K.L.

1998-01-01

This report investigates the solidification process used at 100-N Basin to solidify the N Basin sediment and assesses the N Basin process for application to the K Basin sludge residue material. This report also includes a discussion of a solidification process for stabilizing filters. The solidified matrix must be compatible with the Environmental Remediation Disposal Facility acceptance criteria

An Assessment of Technologies to Provide Extended Sludge Retrieval from Underground Storage Tanks at the Hanford Site

Energy Technology Data Exchange (ETDEWEB)

JA Bamberger

2000-08-02

The purpose of this study was to identify sludge mobilization technologies that can be readily installed in double-shell tanks along with mixer pumps to augment mixer pump operation when mixer pumps do not adequately mobilize waste. The supplementary technologies will mobilize sludge that may accumulate in tank locations out-of-reach of the mixer-pump jet and move the sludge into the mixer-pump range of operation. The identified technologies will be evaluated to determine if their performances and configurations are adequate to meet requirements developed for enhanced sludge removal systems. The study proceeded in three parallel paths to identify technologies that: (1) have been previously deployed or demonstrated in radioactive waste tanks, (2) have been specifically evaluated for their ability to mobilize or dislodge waste simulants with physical and theological properties similar to those anticipated during waste retrieval, and (3) have been used in similar industrial conditions, bu t not specifically evaluated for radioactive waste retrieval.

An Assessment of Technologies to Provide Extended Sludge Retrieval from Underground Storage Tanks at the Hanford Site

International Nuclear Information System (INIS)

JA Bamberger

2000-01-01

The purpose of this study was to identify sludge mobilization technologies that can be readily installed in double-shell tanks along with mixer pumps to augment mixer pump operation when mixer pumps do not adequately mobilize waste. The supplementary technologies will mobilize sludge that may accumulate in tank locations out-of-reach of the mixer-pump jet and move the sludge into the mixer-pump range of operation. The identified technologies will be evaluated to determine if their performances and configurations are adequate to meet requirements developed for enhanced sludge removal systems. The study proceeded in three parallel paths to identify technologies that: (1) have been previously deployed or demonstrated in radioactive waste tanks, (2) have been specifically evaluated for their ability to mobilize or dislodge waste simulants with physical and theological properties similar to those anticipated during waste retrieval, and (3) have been used in similar industrial conditions, but not specifically evaluated for radioactive waste retrieval

CHARACTERIZATION AND ACTUAL WASTE TEST WITH TANK 5F SAMPLES

International Nuclear Information System (INIS)

Fletcher, D.

2007-01-01

to be water-soluble consistent with the determined composition. The analytical data for the solid residues filtered from the oxalic acid solution and filtered oxalic acid indicate a large portion of the Tank 5F sludge used in the tank cleaning test dissolved into the oxalic acid. The results of a material balance calculation indicate a high percentage of the iron, uranium, sodium, and aluminum dissolved during both tests. Approximately half of the manganese, a small portion of the plutonium, and essentially none of the nickel dissolved during the tank cleaning tests. Additionally, the results show slightly higher dissolution of the sludge in the 75 C test compared to the 50 C test however, the amount of sludge dissolution gained by using the higher temperature remains small. Some uncertainty remains with respect to the amount of plutonium dissolved in the tank cleaning test. The neutralization of the filtered oxalic acid solutions from the cleaning test produced a large volume of solids (∼2X the original sludge mass after filtration and air drying). A large portion of the increase in solids could be attributed to the formation of sodium oxalate. The data from analysis of the solid residues filtered from the neutralization tests and the filtrate obtained indicate most of the iron, uranium, manganese, and a large portion of the aluminum precipitated during the neutralization tests. The data for the 50 C test and the 75 C test show good agreement with the exception of the amount of aluminum precipitated from the neutralization. The slower addition rate of the oxalic acid filtrate to the simulated Tank 7F supernate in the 75 C test might account for the smaller amount of aluminum precipitated and differences in the particle size/morphology and composition of the particulates. Some evidence of uranium separation from other sludge elements appears in the 75 C data. Data collected from the tank cleaning and neutralization tests indicates most of the uranium dissolved

Candidate reagents and procedures for the dissolution of Hanford Site single-shell tank sludges

International Nuclear Information System (INIS)

Schulz, W.W.; Kupfer, M.J.

1991-10-01

At least some of the waste in the 149 single-shell tanks (SST) at the US Department of Energy (DOE) Hanford Site will be retrieved, treated, and disposed of. Although the importance of devising efficient and cost-effective sludge dissolution procedures has long been recognized, a concerted bench-scale effort to devise and test such procedures with actual solids representative of those in Hanford Site SSTs has not been performed. Reagents that might be used, either individually or serially, to dissolve sludges include HNO 3 , HNO 3 -oxalic acid, and HNO 3 -HF. This report consolidates and updates perspectives and recommendations concerning reagents and procedures for dissolving Hanford Site SST and selected double-shell tank (DST) sludges. The principal objectives of this report are as follows: (1) Compile and review existing experimental data on dissolution of actual Hanford Site SST and DST sludges. (2) Further inform Hanford Site engineers and scientists concerning the utility of combinations of thermally unstable complexants (TUCS) reagents and various reducing agents for dissolving SST and DST sludges. (This latter technology has recently been explored at the Argonne National Laboratory.) (3) Provide guidance in laying out a comprehensive experimental program to develop technology for dissolving all types of Hanford Site SST and DST sludges. 6 refs., 1 fig., 4 tabs

Activated sludge mass reduction and biodegradability of the endogenous residues by digestion under different aerobic to anaerobic conditions: Comparison and modeling.

Science.gov (United States)

Martínez-García, C G; Fall, C; Olguín, M T

2016-03-01

This study was performed to identify suitable conditions for the in-situ reduction of excess sludge production by intercalated digesters in recycle-activated sludge (RAS) flow. The objective was to compare and model biological sludge mass reduction and the biodegradation of endogenous residues (XP) by digestion under hypoxic, aerobic, anaerobic, and five intermittent-aeration conditions. A mathematical model based on the heterotrophic endogenous decay constant (bH) and including the biodegradation of XP was used to fit the long-term data from the digesters to identify and estimate the parameters. Both the bH constant (0.02-0.05 d(-1)) and the endogenous residue biodegradation constant (bP, 0.001-0.004 d(-1)) were determined across the different mediums. The digesters with intermittent aeration cycles of 12 h-12 h and 5 min-3 h (ON/OFF) were the fastest, compared to the aerobic reactor. The study provides a basis for rating RAS-digester volumes to avoid the accumulation of XP in aeration tanks. Copyright © 2015 Elsevier Ltd. All rights reserved.

Drying of residue and separation of nitrate salts in the sludge waste for the lagoon sludge treatment

International Nuclear Information System (INIS)

Hwang, D. S.; Lee, K. I.; Choi, Y. D.; Hwang, S. T.; Park, J. H.

2003-01-01

This study investigated the dissolution property of nitrate salts in the dissolution process by water and the drying property of residue after separating nitrates in a series of the processes for the sludge treatment. Desalination was carried out with the adding ratio of water and drying property was analyzed by TG/DTA, FTIR, and XRD. Nitrate salts involved in the sludge were separated over 97% at the water adding ratio of 2.5. But a small quantity of calcium and sodium nitrate remained in the residue These were decomposed over 600 .deg. C and calcium carbonate, which was consisted mainly of residue, was decomposed into calcium oxide over 750 .deg. C. The residue have to be decomposed over 800 .deg. C to converse uranyl nitrate of six value into the stable U 3 O 8 of four value. As a result of removing the nitrates at the water adding ratio of 2.5 and drying the residue over 900 .deg. C, volume of the sludge waste decreased over 80%

C-tank transfers: Transuranic sludge removal from the C-1, C-2, and W-23 waste storage tanks at Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Dahl, T.L.; Lay, A.C.; Taylor, S.A.; Moore, J.W.

1999-01-01

Two fluidic pulse jet mixing systems were used to successfully mobilize remote-handled transuranic sludge for retrieval from three 50,000-gal horizontal waste storage tanks at Oak Ridge National Laboratory (ORNL). The results of this operation indicate that the pulse jet system should be considered for mixing and bulk retrieval of sludges in other vertical and horizontal waste tanks at ORNL and at other U.S. Department of Energy sites

Hanford tank residual waste - Contaminant source terms and release models

International Nuclear Information System (INIS)

Deutsch, William J.; Cantrell, Kirk J.; Krupka, Kenneth M.; Lindberg, Michael L.; Jeffery Serne, R.

2011-01-01

Highlights: → Residual waste from five Hanford spent fuel process storage tanks was evaluated. → Gibbsite is a common mineral in tanks with high Al concentrations. → Non-crystalline U-Na-C-O-P ± H phases are common in the U-rich residual. → Iron oxides/hydroxides have been identified in all residual waste samples. → Uranium release is highly dependent on waste and leachant compositions. - Abstract: Residual waste is expected to be left in 177 underground storage tanks after closure at the US Department of Energy's Hanford Site in Washington State, USA. In the long term, the residual wastes may represent a potential source of contamination to the subsurface environment. Residual materials that cannot be completely removed during the tank closure process are being studied to identify and characterize the solid phases and estimate the release of contaminants from these solids to water that might enter the closed tanks in the future. As of the end of 2009, residual waste from five tanks has been evaluated. Residual wastes from adjacent tanks C-202 and C-203 have high U concentrations of 24 and 59 wt.%, respectively, while residual wastes from nearby tanks C-103 and C-106 have low U concentrations of 0.4 and 0.03 wt.%, respectively. Aluminum concentrations are high (8.2-29.1 wt.%) in some tanks (C-103, C-106, and S-112) and relatively low ( 2 -saturated solution, or a CaCO 3 -saturated water. Uranium release concentrations are highly dependent on waste and leachant compositions with dissolved U concentrations one or two orders of magnitude higher in the tests with high U residual wastes, and also higher when leached with the CaCO 3 -saturated solution than with the Ca(OH) 2 -saturated solution. Technetium leachability is not as strongly dependent on the concentration of Tc in the waste, and it appears to be slightly more leachable by the Ca(OH) 2 -saturated solution than by the CaCO 3 -saturated solution. In general, Tc is much less leachable (<10 wt.% of the

Sludge Washing and Demonstration of the DWPF Nitric/Formic Flowsheet in the SRNL Shielded Cells for Sludge Batch 9 Qualification

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Newell, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Martino, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Johnson, F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-11-01

Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (SRR) to qualify the next batch of sludge – Sludge Batch 9 (SB9). Current practice is to prepare sludge batches in Tank 51 by transferring sludge to Tank 51 from other tanks. The sludge is washed and transferred to Tank 40, the current Defense Waste Process Facility (DWPF) feed tank. Prior to sludge transfer from Tank 51 to Tank 40, the Tank 51 sludge must be qualified. SRNL qualifies the sludge in multiple steps. First, a Tank 51 sample is received, then characterized, washed, and again characterized. SRNL then demonstrates the DWPF Chemical Process Cell (CPC) flowsheet with the sludge. The final step of qualification involves chemical durability measurements of glass fabricated in the DWPF CPC demonstrations. In past sludge batches, SRNL had completed the DWPF demonstration with Tank 51 sludge. For SB9, SRNL has been requested to process a blend of Tank 51 and Tank 40 at a targeted ratio of 44% Tank 51 and 56% Tank 40 on an insoluble solids basis.

Effect of enzymes on anaerobic digestion of primary sludge and septic tank performance.

Science.gov (United States)

Diak, James; Örmeci, Banu; Kennedy, Kevin J

2012-11-01

Enzyme additives are believed to improve septic tank performance by increasing the hydrolysis and digestion rates and maintaining a healthy microbial population. Previous studies reported mixed results on the effectiveness of enzymes on mesophilic and thermophilic digestion, and it is not clear whether enzymes would be effective under septic tank conditions where there is no heating or mixing, quantities of enzymes added are small, and they can be washed out quickly. In this study, batch reactors and continuous-flow reactors designed and operated as septic tanks were used to evaluate whether enzymatic treatment would increase the hydrolysis and digestion rates in primary sludge. Total solids, volatile solids, total suspended solids, total and soluble chemical oxygen demand, concentrations of protein, carbohydrate, ammonia and volatile acids in sludge and effluent samples were measured to determine the differences in digestion rates in the presence and absence of enzymes. Overall, no significant improvement was observed in enzyme-treated reactors compared with the control reactors.

Modeling water retention of sludge simulants and actual saltcake tank wastes

International Nuclear Information System (INIS)

Simmons, C.S.

1996-07-01

The Ferrocyanide Tanks Safety Program managed by Westinghouse hanford Company has been concerned with the potential combustion hazard of dry tank wastes containing ferrocyanide chemical in combination with nitrate salts. Pervious studies have shown that tank waste containing greater than 20 percent of weight as water could not be accidentally ignited. Moreover, a sustained combustion could not be propagated in such a wet waste even if it contained enough ferrocyanide to burn. Because moisture content is a key critical factor determining the safety of ferrocyanide-containing tank wastes, physical modeling was performed by Pacific Northwest National laboratory to evaluate the moisture-retaining behavior of typical tank wastes. The physical modeling reported here has quantified the mechanisms by which two main types of tank waste, sludge and saltcake, retain moisture in a tank profile under static conditions. Static conditions usually prevail after a tank profile has been stabilized by pumping out any excess interstitial liquid, which is not naturally retained by the waste as a result of physical forces such as capillarity

WWTP Process Tank Modelling

DEFF Research Database (Denmark)

Laursen, Jesper

The present thesis considers numerical modeling of activated sludge tanks on municipal wastewater treatment plants. Focus is aimed at integrated modeling where the detailed microbiological model the Activated Sludge Model 3 (ASM3) is combined with a detailed hydrodynamic model based on a numerical...... solution of the Navier-Stokes equations in a multiphase scheme. After a general introduction to the activated sludge tank as a system, the activated sludge tank model is gradually setup in separate stages. The individual sub-processes that are often occurring in activated sludge tanks are initially...... hydrofoil shaped propellers. These two sub-processes deliver the main part of the supplied energy to the activated sludge tank, and for this reason they are important for the mixing conditions in the tank. For other important processes occurring in the activated sludge tank, existing models and measurements...

TANK 12 SLUDGE CHARACTERIZATION AND ALUMINUM DISSOLUTION DEMONSTRATION

International Nuclear Information System (INIS)

Reboul, S.; Hay, Michael; Zeigler, Kristine; Stone, Michael

2009-01-01

A 3-L sludge slurry sample from Tank 12 was characterized and then processed through an aluminum dissolution demonstration. The dominant constituent of the sludge was found to be aluminum in the form of boehmite. The iron content was minor, about one-tenth that of the aluminum. The salt content of the supernatant was relatively high, with a sodium concentration of ∼7 M. Due to these characteristics, the yield stress and plastic viscosity of the unprocessed slurry were relatively high (19 Pa and 27 cP), and the settling rate of the sludge was relatively low (∼20% settling over a two and a half week period). Prior to performing aluminum dissolution, plutonium and gadolinium were added to the slurry to simulate receipt of plutonium waste from H-Canyon. Aluminum dissolution was performed over a 26 day period at a temperature of 65 C. Approximately 60% of the insoluble aluminum dissolved during the demonstration, with the rate of dissolution slowing significantly by the end of the demonstration period. In contrast, approximately 20% of the plutonium and less than 1% of the gadolinium partitioned to the liquid phase. However, about a third of the liquid phase plutonium became solubilized prior to the dissolution period, when the H-Canyon plutonium/gadolinium simulant was added to the Tank 12 slurry. Quantification of iron dissolution was less clear, but appeared to be on the order of 1% based on the majority of data (a minor portion of the data suggested iron dissolution could be as high as 10%). The yield stress of the post-dissolution slurry (2.5 Pa) was an order of magnitude lower than the initial slurry, due most likely to the reduced insoluble solids content caused by aluminum dissolution. In contrast, the plastic viscosity remained unchanged (27 cP). The settling rate of the post-dissolution slurry was higher than the initial slurry, but still relatively low compared to settling of typical high iron content/low salt content sludges. Approximately 40% of the

Pathogen reduction in septic tank sludge through vermicomposting using Eisenia fetida.

Science.gov (United States)

Rodríguez-Canché, L G; Cardoso Vigueros, L; Maldonado-Montiel, T; Martínez-Sanmiguel, M

2010-05-01

This study evaluated the potential of earthworms (Eisenia fetida) to remove pathogens from the sludge from septic tanks. Three earthworm population densities, equivalent to 1, 2, and 2.5kgm(-2), were tested for pathogen removal from sludge. The experimental phase lasted 60days, starting from the initial earthworm inoculation. After 60days, it was found that earthworms reduced concentrations of fecal coliforms, Salmonella spp., and helminth ova to permissible levels (<1000MPN/g, <3MPN/g, and <1viable ova/g on a dry weight basis, respectively) in accordance with Official Mexican Standard of environmental protection (NOM-004-SEMARNAT-2002) (SEMARNAT, 2002). Thus, sludge treatment with earthworms generated Class A biosolids, useful for forest, agricultural, and soil improvement. Copyright 2009 Elsevier Ltd. All rights reserved.

Nondestructive assay of plutonium residue in horizontal storage tanks

International Nuclear Information System (INIS)

Marsh, S.F.

1985-01-01

Aqueous plutonium recovery and purification processes often involve the temporary storage of plutonium solutions in holding tanks. Because plutonium is known to precipitate from aqueous solutions under certain conditions, there is a continuing need to assay emptied tanks for plutonium residue. A portable gamma spectrometer system, specifically designed for this purpose, provides rapid assay of such plutonium residues in horizontal storage tanks. A means is thus available for the nondestructive analysis of these tanks on a regular schedule to ensure that significant deposits of plutonium are not allowed to accumulate. 5 figs

Minimization of Excess Sludge in Activated Sludge Systems

Directory of Open Access Journals (Sweden)

Sayed Ali Reza Momeni

2006-01-01

Full Text Available The disposal of excess sludge from wastewater treatment plant represents a rising challenge in activated sludge processes. Hence, the minimization of excess sludge production was investigated by increasing the dissolved oxygen in aeration basin. Units of the pilot include: Primary sedimentation tank, aeration basin, secondary sedimentation tank, and return sludge tank. Volume of aeration basin is 360 l and influent flow rate is 90 L/h. Influent of pilot is taken from effluent of grit chamber of Isfahan's North Wastewater treatment plant. The experiments were done on different parts of pilot during the 5 month of study. Results show that increase of dissolved oxygen in aeration tank affect on decrease of excess sludge. Increase of dissolved oxygen from 0.5 to 4.5 mg/L resulted in 25% decrease of excess sludge. Variation of dissolved oxygen affect on settleability of sludge too. By increase of dissolved oxygen, SVI decreased and then increased. Value of 1-3 mg/L was the adequate range of dissolved oxygen by settleability of sludge and optimum range was 2-2.5 mg/L. It could be concluded by increasing of dissolved oxygen up to of 3 mg/L, sludge settleability significant decreased.

Research on jet mixing of settled sludges in nuclear waste tanks at Hanford and other DOE sites: A historical perspective

Energy Technology Data Exchange (ETDEWEB)

Powell, M.R.; Onishi, Y.; Shekarriz, R.

1997-09-01

Jet mixer pumps will be used in the Hanford Site double-shell tanks to mobilize and mix the settled solids layer (sludge) with the tank supernatant liquid. Predicting the performance of the jet mixer pumps has been the subject of analysis and testing at Hanford and other U.S. Department of Energy (DOE) waste sites. One important aspect of mixer pump performance is sludge mobilization. The research that correlates mixer pump design and operation with the extent of sludge mobilization is the subject of this report. Sludge mobilization tests have been conducted in tanks ranging from 1/25-scale (3 ft-diameter) to full scale have been conducted at Hanford and other DOE sites over the past 20 years. These tests are described in Sections 3.0 and 4.0 of this report. The computational modeling of sludge mobilization and mixing that has been performed at Hanford is discussed in Section 5.0.

Research on jet mixing of settled sludges in nuclear waste tanks at Hanford and other DOE sites: A historical perspective

International Nuclear Information System (INIS)

Powell, M.R.; Onishi, Y.; Shekarriz, R.

1997-09-01

Jet mixer pumps will be used in the Hanford Site double-shell tanks to mobilize and mix the settled solids layer (sludge) with the tank supernatant liquid. Predicting the performance of the jet mixer pumps has been the subject of analysis and testing at Hanford and other U.S. Department of Energy (DOE) waste sites. One important aspect of mixer pump performance is sludge mobilization. The research that correlates mixer pump design and operation with the extent of sludge mobilization is the subject of this report. Sludge mobilization tests have been conducted in tanks ranging from 1/25-scale (3 ft-diameter) to full scale have been conducted at Hanford and other DOE sites over the past 20 years. These tests are described in Sections 3.0 and 4.0 of this report. The computational modeling of sludge mobilization and mixing that has been performed at Hanford is discussed in Section 5.0

Ferrocyanide Safety Program: Waste tank sludge rheology within a hot spot or during draining

International Nuclear Information System (INIS)

Fauske, H.K.; Cash, R.J.

1993-11-01

The conditions under which ferrocyanide waste sludge flows as a homogeneous non-Newtonian two-phase (solid precipitate-liquid) mixture rather than as a liquid through a porous medium (of stationary precipitate) are examined theoretically, based on the notion that the preferred rheological behavior of the sludge is the one which imposes the least resistance to the sludge flow. The homogeneous two-phase mixture is modeled as a power-law fluid and simple criteria are derived that show that the homogeneous power-law sludge-flow is a much more likely flow situation than the porous medium model of sludge flow. The implication of this finding is that the formation of a hot spot or the drainage of sludge from a waste tank are not likely to result in the uncovering (drying) and subsequent potential overheating of the reactive-solid component of the sludge

SLUDGE BATCH 5 ACCEPTANCE EVALUATION RADIONUCLIDE CONCENTRATIONS IN TANK 51 SB5 QUALIFICATION SAMPLE PREPARED AT SRNL

International Nuclear Information System (INIS)

Bannochie, C; Ned Bibler, N; David Diprete, D

2008-01-01

Presented in this report are radionuclide concentrations required as part of the program of qualifying Sludge Batch Five (SB5) for processing in the Defense Waste Processing Facility (DWPF). Part of this SB5 material is currently in Tank 51 being washed and prepared for transfer to Tank 40. The acceptance evaluation needs to be completed prior to the transfer of the material in Tank 51 to Tank 40 to complete the formation of SB5. The sludge slurry in Tank 40 has already been qualified for DWPF and is currently being processed as SB4. The radionuclide concentrations were measured or estimated in the Tank 51 SB5 Qualification Sample prepared at Savannah River National Laboratory (SRNL). This sample was prepared from the three liter sample of Tank 51 sludge slurry taken on March 21, 2008. The sample was delivered to SRNL where it was initially characterized in the Shielded Cells. Under direction of the Liquid Waste Organization it was then modified by five washes, six decants, an addition of Pu/Be from Canyon Tank 16.4, and an addition of NaNO2. This final slurry now has a composition expected to be similar to that of the slurry in Tank 51 after final preparations have been made for transfer of that slurry to Ta Determining the radionuclide concentrations in this Tank 51 SB5 Qualification Sample is part of the work requested in Technical Task Request (TTR) No. HLW-DWPF-TTR-2008-0010. The work with this qualification sample is covered by a Task Technical and Quality Assurance Plan and an Analytical Study Plan. The radionuclides included in this report are needed for the DWPF Radiological Program Evaluation, the DWPF Waste Acceptance Criteria (TSR/WAC) Evaluation, and the DWPF Solid Waste Characterization Program (TTR Task 2). Radionuclides required to meet the Waste Acceptance Product Specifications (TTR Task 5) will be measured at a later date after the slurry from Tank 51 has been transferred to Tank 40. Then a sample of the as-processed SB5 will be taken and

Characterization of underground storage tank sludge using fourier transform infrared photoacoustic spectroscopy

International Nuclear Information System (INIS)

Luo, S.; Bajic, S.J.; Jones, R.W.

1994-01-01

Analysis of underground storage tank (UST) contents is critical for the determination of proper disposal protocols and storage procedures of nuclear waste materials. Tank volume reduction processes during the 1940's and 50's have produced a waste form that compositionally varies widely and has a consistency that ranges from paste like sludge to saltcake. The heterogeneity and chemical reactivity of the waste form makes analysis difficult by most conventional methods which require extensive sample preparation. In this paper, a method is presented to characterize nuclear waste from UST's at the Westinghouse Hanford Site in Washington State, using Fourier transform infrared-photoacoustic spectroscopy (FTIR-PAS). FTIR-PAS measurements on milligram amounts of surrogate sludge samples have been used to accurately identify phosphate, sulfate, nitrite, nitrate and ferrocyanide components. A simple sample preparation method was followed to provide a reproducible homogeneous sample for quantitative analysis. The sample preparation method involved freeze drying the sludge sample prior to analysis to prevent the migration of soluble species. Conventional drying (e.g., air or, oven) leads to the formation of crystals near the surface where evaporation occurs. Sample preparation as well as the analytical utility of this method will be discussed

INVESTIGATING SUSPENSION OF MST, CST, AND SIMULATED SLUDGE SLURRIES IN A PILOT-SCALE WASTE TANK

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.; Qureshi, Z.; Restivo, M.; Steeper, T.; Williams, M.

2011-05-24

The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank (i.e., Tank 41H) to house the process. Savannah River National Laboratory (SRNL) is conducting pilot-scale mixing tests to determine the pump requirements for suspending and resuspending monosodium titanate (MST), crystalline silicotitanate (CST), and simulated sludge. The purpose of this pilot scale testing is for the pumps to resuspend the MST, CST, and simulated sludge particles so that they can be removed from the tank, and to suspend the MST so it can contact strontium and actinides. The pilot-scale tank is a 1/10.85 linear scaled model of Tank 41H. The tank diameter, tank liquid level, pump nozzle diameter, pump elevation, and cooling coil diameter are all 1/10.85 of their dimensions in Tank 41H. The pump locations correspond to the proposed locations in Tank 41H by the SCIX program (Risers B5, B3, and B1). Previous testing showed that three Submersible Mixer Pumps (SMPs) will provide sufficient power to initially suspend MST in an SRS waste tank, and to resuspend MST that has settled in a waste tank at nominal 45 C for four weeks. The conclusions from this analysis are: (1) Three SMPs will be able to resuspend more than 99.9% of the MST and CST that has settled for four weeks at nominal 45 C. The testing shows the required pump discharge velocity is 84% of the maximum discharge velocity of the pump. (2) Three SMPs will be able to resuspend more than 99.9% of the MST, CST, and simulated sludge that has settled for four weeks at nominal 45 C. The testing shows the required pump discharge velocity is 82% of the maximum discharge velocity of the pump. (3) A contact time of 6-12 hours is needed for strontium sorption by MST in a jet mixed tank with cooling coils, which is consistent with bench-scale testing and actinide removal process (ARP) operation.

Influence of sludge properties and hydraulic loading on the performance of secondary settling tanks--full-scale operational results.

Science.gov (United States)

Vestner, R J; Günthert, F Wolfgang

2004-01-01

Full-scale investigations at a WWTP with a two-stage secondary settling tank process revealed relationships between significant operating parameters and performance in terms of effluent suspended solids concentration. Besides common parameters (e.g. surface overflow rate and sludge volume loading rate) feed SS concentration and flocculation time must be considered. Concentration of the return activated sludge may help to estimate the performance of existing secondary settling tanks.

F-Canyon Sludge Physical Properties

International Nuclear Information System (INIS)

Poirier, M. R.; Hansen, P. R.; Fink, S. D.

2005-01-01

The Site Deactivation and Decommissioning (SDD) Organization is evaluating options to disposition the 800 underground tanks (including removal of the sludge heels from these tanks). To support this effort, DandD requested assistance from Savannah River National Laboratory (SRNL) personnel to determine the pertinent physical properties to effectively mobilize the sludge from these tanks (Tanks 804, 808, and 809). SDD provided SRNL with samples of the sludge from Tanks 804, 808, and 809. The authors measured the following physical properties for each tank: particle settling rate, shear strength (i.e., settled solids yield stress), slurry rheology (i.e., yield stress and consistency), total solids concentration in the sludge, soluble solids concentration of the sludge, sludge density, and particle size distribution

Colloidal agglomerates in tank sludge and their impact on waste processing

International Nuclear Information System (INIS)

Tingey, J.M.; Bunker, B.C.; Graff, G.L.; Keefer, K.D.; Lea, A.S.; Rector, D.R.

1999-01-01

Disposal of millions of gallons of existing radioactive wastes in underground storage tanks is a major remediation activity for the US Department of Energy. These wastes include a substantial volume of insoluble sludges consisting of submicron colloidal particles. Processing these sludges under the proposed processing conditions presents unique challenges in retrieval transport, separation, and solidification of these waste streams. Depending on processing conditions, these colloidal particles can form agglomerated networks having high viscosities that could clog transfer lines or produce high volumes of low-density sediments that interfere with solid-liquid separations. Under different conditions, these particles can be dispersed to form very fine suspended particles that do not settle. Given the wide range of waste chemistries present at Department of Energy sites, it is impractical to measure the properties of all treatment procedures. Under the current research activities, the underlying principles of colloid chemistry and physics are being studied to predict and eventually control the physical properties of sludge suspensions and sediment layers in tank wastes and other waste processing streams. Proposed tank processing strategies include retrieval transport, and solid-liquid separations in basic (pH 10 to 14), high ionic strength (0.1 to 1.0 M) salt solutions. The effect of salt concentration, ionic strength, and salt composition on the physical properties such as viscosity, agglomerate size, and sedimentation of model suspensions containing mixtures of one or two of the major components found in actual wastes have been measured to understand how agglomeration influences processing. Property models developed from theory and experiment on these simple suspensions are then applied to explain the results obtained on actual wastes

Continuosly Stirred Tank Reactor Parameters That Affect Sludge Batch 6 Simulant Properties

International Nuclear Information System (INIS)

Newell, J.; Lambert, D.; Stone, M.; Fernandez, A.

2010-01-01

The High Level Radioactive Waste (HLW) Sludge in Savannah River Site (SRS) waste tanks was produced over a period of over 60 years by neutralizing the acidic waste produced in the F and H Separations Canyons with sodium hydroxide. The HLW slurries have been stored at free hydroxide concentrations above 1 M to minimize the corrosion of the carbon steel waste tanks. Sodium nitrite is periodically added as a corrosion inhibitor. The resulting waste has been subjected to supernate evaporation to minimize the volume of the stored waste. In addition, some of the waste tanks experienced high temperatures so some of the waste has been at elevated temperatures. Because the waste is radioactive, the waste is transforming through the decay of shorter lived radioactive species and the radiation damage that the decay releases. The goal of the Savannah River National Laboratory (SRNL) simulant development program is to develop a method to produce a sludge simulant that matches both the chemical and physical characteristics of the HLW without the time, temperature profile, chemical or radiation exposure of that of the real waste. Several different approaches have been taken historically toward preparing simulated waste slurries. All of the approaches used in the past dozen years involve some precipitation of the species using similar chemistry to that which formed the radioactive waste solids in the tank farm. All of the approaches add certain chemical species as commercially available insoluble solid compounds. The number of species introduced in this manner, however, has varied widely. All of the simulant preparation approaches make the simulated aqueous phase by adding the appropriate ratios of various sodium salts. The simulant preparation sequence generally starts with an acidic pH and ends up with a caustic pH (typically in the 10-12 range). The current method for making sludge simulant involves the use of a temperature controlled continuously stirred tank reactor (CSTR

Hazardous waste management in pipeline terminal: a multi-pronged approach for safe disposal of tank bottom sludge

Energy Technology Data Exchange (ETDEWEB)

Ammanna, John [Indian Oil Corporation Limited (IOCL), Mumbai (India)

2009-12-19

Indian Oil Corporation Ltd., Pipeline Division owns and operates the 1850 Km long Salaya-Mathura Crude Oil Pipeline (SMPL) with installed capacity of 21 MMTPA. Almost 25 types of crude [90% imported and 10% indigenous] are received into 13 on-shore tanks at Vadinar (the Mother Station of SMPL) through 2 Nos. SPM's anchored in the Arabian Sea and located on the west coast of India in the Gulf of Kutch. Larger quantities of tank bottom sludge that gets generated in the terminal during tank M and I pose serious environmental hazards, as procedures for handling, treatment and disposal of hazardous waste are not well established. With increasingly stringent Environmental norms being enforced by Statutory / Regulatory Authorities, storage of hazardous solid waste in lagoons and its disposal through designated approved agencies within the specified time frame, becomes extremely difficult. This paper seeks to address this issue by putting forth an innovative approach to hazardous waste management in pipeline terminals having large crude oil tank farms that has been adopted at Indian Oil Corporation's Vadinar terminal of SMPL where a multi-pronged approach for safe disposal of tank bottom sludge has been successfully implemented. The terminal has since become a 'Zero sludge location'. (author)

Reuse of residual sludge from stone-processing: differences and similarities between sludge coming from carbonate and silicate stones

Science.gov (United States)

Careddu, Nicola; Antonella Dino, Giovanna

2015-04-01

Residual sludge coming from dimension stone working activities represents a serious environmental and economic problem both for Stone Industry and citizens. Indeed, most of time, residual sludge is landfilled because of the difficulties to recover it; such difficulties are mainly connected to local legislation and a lack of proper protocols. In general, it is possible to individuate two different categories of sludge: residual sludge coming from carbonate rocks (CS) and those coming from silicate rocks (SS). Both of them are characterised by a very fine size distribution. CS is composed mainly by the same compounds of the processed stones (marble, limestone, travertine). The reason of this is related to the very slow wear of diamond tools during processing which entails a negligible content of heavy metals. CS becomes very interesting, from an economic point of view, when it has a CaCO3 grade > 95 %. On the contrary, SS is characterised by high heavy metal and TPH content. Residual sludge from the processing of silicate rocks can be split in three different sub-categories, depending on the way they are produced, and in particular: sludge from gangsaw using abrasive steel shot (GSS), sludge from multi diamond-saw block cutter (DBC), and mixed sludge (MS) from gangsaw and block cutter. These three sub-categories show different problems connected to heavy metal content, indeed on the one hand GSS is characterised by a high percentage of Ni, Cr, Cu, etc., on the other hand DBC is characterised by Co and Cu high content. In general, sludge, management of which in Italy is administered in accordance with the Italian Legislative Decree 152/06, can be used as waste from for environmental restoration or for cement plants. Several researches investigate the possible reuse of these materials but, at present time, there is no evidence of its systematic recovery as "recycled product" or "by-product". On the basis of the results of these researches it is possible to highlight

Innovative tank emptying system for the retrieval of salt, sludge and IX resins from storage tanks of NPPs

International Nuclear Information System (INIS)

Karl Froschauer; Holger Witing; Bernhard Christ

2006-01-01

RWE NUKEM recently developed a new Tank Emptying System (TESY) for the extraction of stored radioactive boric acid/borate salt blocks, sludge and IX resin from NPP stainless steel tanks of several hundred cubic meters content in Russia. RWE NUKEM has chosen the emptying concept consisting of a tracked submersible vehicle ('Crawler'), with jet nozzles for solution, agitation and fluidization, and a suction head to pick up the generated solution or suspension respectively. With the employment of RWE NUKEM's TESY system, spent radioactive salt deposits, ion-exchange resins and sludge, can be emptied and transferred out of the tank. The sediment, crystallized and settled during storage, will be agitated with increased temperature and suitable pH value and then picked up in form of a suspension or solution directly at the point of mobilization. This new Tank Emptying System concept enables efficiently to retrieve stored salt and other sediment waste, reduces operating time, safes cost for spare parts, increases the safety of operation and minimizes radiation exposure to personnel. All emptying tasks are performed remotely from a panel board and TV monitor located in a central control room. The TESY system consists of the following main components: glove box, crawler, submersible pump, heater, TV camera and spot light, control panel and monitor, water separation and feed unit, sodium hydroxide dosing unit. The system is specially requested for the removal of more than 2,500 cubic meter salt solution generated from the dissolution of some 300 cubic meter crystallized salt deposit per tank and per year. The TESY system is able to dissolve efficiently the salts and retrieve solutions and other liquefied suspensions. TESY is adaptable to all liquid waste storage facilities and especially deployable for tanks with limited access openings (<550 mm)

Hanford Tanks 241-C-202 and 241-C-203 Residual Waste Contaminant Release Models and Supporting Data

Energy Technology Data Exchange (ETDEWEB)

Deutsch, William J.; Krupka, Kenneth M.; Lindberg, Michael J.; Cantrell, Kirk J.; Brown, Christopher F.; Mattigod, Shas V.; Schaef, Herbert T.; Arey, Bruce W.

2007-09-13

As directed by Congress, the U. S. Department of Energy (DOE) established the Office of River Protection in 1998 to manage DOE's largest, most complex environmental cleanup project – retrieval of radioactive waste from Hanford tanks for treatment and eventual disposal. Sixty percent by volume of the nation's high-level radioactive waste is stored at Hanford in aging deteriorating tanks. If not cleaned up, this waste is a threat to the Columbia River and the Pacific Northwest. CH2M Hill Hanford Group, Inc., is the Office of River Protection's prime contractor responsible for the storage, retrieval, and disposal of Hanford's tank waste. As part of this effort, CH2M HILL Hanford Group, Inc. contracted with Pacific Northwest National Laboratory (PNNL) to develop release models for key contaminants that are present in residual sludge remaining after closure of Hanford Tanks 241-C-203 (C-203) and 241-C-204 (C-204). The release models were developed from data generated by laboratory characterization and testing of samples from these two tanks. These release models are being developed to support the tank closure risk assessments performed by CH2M HILL Hanford Group, Inc., for DOE.

EFFECTIVENESS OF USING DILUTE OXALIC ACID TO DISSOLVE HIGH LEVEL WASTE IRON BASED SLUDGE SIMULANT

International Nuclear Information System (INIS)

Ketusky, E

2008-01-01

At the Savannah River Site (SRS), near Aiken South Carolina, there is a crucial need to remove residual quantities of highly radioactive iron-based sludge from large select underground storage tanks (e.g., 19,000 liters of sludge per tank), in order to support tank closure. The use of oxalic acid is planned to dissolve the residual sludge, hence, helping in the removal. Based on rigorous testing, primarily using 4 and 8 wt% oxalic acid solutions, it was concluded that the more concentrated the acid, the greater the amount of residual sludge that would be dissolved; hence, a baseline technology on using 8 wt% oxalic acid was developed. In stark contrast to the baseline technology, reports from other industries suggest that the dissolution will most effectively occur at 1 wt% oxalic acid (i.e., maintaining the pH near 2). The driver for using less oxalic acid is that less (i.e., moles) would decrease the severity of the downstream impacts (i.e., required oxalate solids removal efforts). To determine the initial feasibility of using 1 wt% acid to dissolve > 90% of the sludge solids, about 19,000 liters of representative sludge was modeled using about 530,000 liters of 0 to 8 wt% oxalic acid solutions. With the chemical thermodynamic equilibrium based software results showing that 1 wt% oxalic acid could theoretically work, simulant dissolution testing was initiated. For the dissolution testing, existing simulant was obtained, and an approximate 20 liter test rig was built. Multiple batch dissolutions of both wet and air-dried simulant were performed. Overall, the testing showed that dilute oxalic acid dissolved a greater fraction of the stimulant and resulted in a significantly larger acid effectiveness (i.e., grams of sludge dissolved/mole of acid) than the baseline technology. With the potential effectiveness confirmed via simulant testing, additional testing, including radioactive sludge testing, is planned

[Research on change process of nitrosation granular sludge in continuous stirred-tank reactor].

Science.gov (United States)

Yin, Fang-Fang; Liu, Wen-Ru; Wang, Jian-Fang; Wu, Peng; Shen, Yao-Liang

2014-11-01

In order to investigate the effect of different types of reactors on the nitrosation granular sludge, a continuous stirred-tank reactor (CSTR) was studied, using mature nitrosation granular sludge cultivated in sequencing batch reactor (SBR) as seed sludge. Results indicated that the change of reactor type and influent mode could induce part of granules to lose stability with gradual decrease in sludge settling ability during the initial period of operation. However, the flocs in CSTR achieved fast granulation in the following reactor operation. In spite of the changes of particle size distribution, e. g. the decreasing number of granules with diameter larger than 2.5 mm and the increasing number of granules with diameter smaller than 0.3 mm, granular sludge held the absolute predominance of sludge morphology in CSTR during the entire experimental period. Moreover, results showed that the change of reactor type and influent mode didn't affect the nitrite accumulation rate which was still kept at about 85% in effluent. Additionally, the average activity of the sludge in CSTR was stronger than that of the seed sludge, because the newly generated small particles in CSTR had higher specific reactive activity than the larger granules.

Stabilization of in-tank residual wastes and external-tank soil contamination for the tank focus area, Hanford tank initiative: Applications to the AX Tank Farm

International Nuclear Information System (INIS)

Balsley, S.D.; Krumhansl, J.L.; Borns, D.J.; McKeen, R.G.

1998-07-01

A combined engineering and geochemistry approach is recommended for the stabilization of waste in decommissioned tanks and contaminated soils at the AX Tank Farm, Hanford, WA. A two-part strategy of desiccation and gettering is proposed for treatment of the in-tank residual wastes. Dry portland cement and/or fly ash are suggested as an effective and low-cost desiccant for wicking excess moisture from the upper waste layer. Getters work by either ion exchange or phase precipitation to reduce radionuclide concentrations in solution. The authors recommend the use of specific natural and man-made compounds, appropriately proportioned to the unique inventory of each tank. A filler design consisting of multilayered cementitous grout with interlayered sealant horizons should serve to maintain tank integrity and minimize fluid transport to the residual waste form. External tank soil contamination is best mitigated by placement of grouted skirts under and around each tank, together with installation of a cone-shaped permeable reactive barrier beneath the entire tank farm. Actinide release rates are calculated from four tank closure scenarios ranging from no action to a comprehensive stabilization treatment plan (desiccant/getters/grouting/RCRA cap). Although preliminary, these calculations indicate significant reductions in the potential for actinide transport as compared to the no-treatment option

Examination of sludge accumulation rates and sludge characteristics for a decentralized community wastewater treatment systems with individual primary clarifier tanks located in Wardsville (Ontario, Canada).

Science.gov (United States)

Lossing, Heather; Champagne, Pascale; McLellan, P James

2010-01-01

In conventional septic systems, settling and partial treatment via anaerobic digestion occurs in the septic tank. One of the byproducts of solids separation in the septic tank is a semi-liquid material known as septage, which must be periodically pumped out. Septage includes the liquid portion within the tank, as well as the sludge that settles at the bottom of the tank and the scum that floats to the surface of the liquid layer. A number of factors can influence septage characteristics, as well as the sludge and scum accumulation rates within the tank. This paper presents the results of a 2007 field sampling study conducted in Wardsville (Ontario, Canada). The field study examined 29 individual residential two-chamber septic tanks in a community serviced by a decentralized wastewater treatment system in operation for approximately 7 years without septage removal. The field investigation provided a comprehensive data set that allowed for statistical analysis of the data to assess the more critical factors influencing solids accumulation rates within each of the clarifier chambers. With this data, a number of predictive models were developed using water usage data for each residence as an explanatory variable.

Sludge Heel Removal By Aluminum Dissolution At Savannah River Site 12390

International Nuclear Information System (INIS)

Keefer, M.

2012-01-01

High Level Waste (HLW) at the Savannah River Site (SRS) is currently stored in aging underground storage tanks. This waste is a complex mixture of insoluble solids, referred to as sludge, and soluble salts. Continued long-term storage of these radioactive wastes poses an environmental risk. Operations are underway to remove and disposition the waste, clean the tanks and fill with grout for permanent closure. Heel removal is the intermediate phase of the waste retrieval and tank cleaning process at SRS, which is intended to reduce the volume of waste prior to treatment with oxalic acid. The goal of heel removal is to reduce the residual amount of radioactive sludge wastes to less than 37,900 liters (10,000 gallons) of wet solids. Reducing the quantity of residual waste solids in the tank prior to acid cleaning reduces the amount of acid required and reduces the amount of excess acid that could impact ongoing waste management processes. Mechanical heel removal campaigns in Tank 12 have relied solely on the use of mixing pumps that have not been effective at reducing the volume of remaining solids. The remaining waste in Tank 12 is known to have a high aluminum concentration. Aluminum dissolution by caustic leaching was identified as a treatment step to reduce the volume of remaining solids and prepare the tank for acid cleaning. Dissolution was performed in Tank 12 over a two month period in July and August, 2011. Sample results indicated that 16,440 kg of aluminum oxide (boehmite) had been dissolved representing 60% of the starting inventory. The evolution resulted in reducing the sludge solids volume by 22,300 liters (5900 gallons), preparing the tank for chemical cleaning with oxalic acid.

SLUDGE HEEL REMOVAL BY ALUMINUM DISSOLUTION AT SAVANNAH RIVER SITE 12390

Energy Technology Data Exchange (ETDEWEB)

Keefer, M.

2012-01-12

High Level Waste (HLW) at the Savannah River Site (SRS) is currently stored in aging underground storage tanks. This waste is a complex mixture of insoluble solids, referred to as sludge, and soluble salts. Continued long-term storage of these radioactive wastes poses an environmental risk. Operations are underway to remove and disposition the waste, clean the tanks and fill with grout for permanent closure. Heel removal is the intermediate phase of the waste retrieval and tank cleaning process at SRS, which is intended to reduce the volume of waste prior to treatment with oxalic acid. The goal of heel removal is to reduce the residual amount of radioactive sludge wastes to less than 37,900 liters (10,000 gallons) of wet solids. Reducing the quantity of residual waste solids in the tank prior to acid cleaning reduces the amount of acid required and reduces the amount of excess acid that could impact ongoing waste management processes. Mechanical heel removal campaigns in Tank 12 have relied solely on the use of mixing pumps that have not been effective at reducing the volume of remaining solids. The remaining waste in Tank 12 is known to have a high aluminum concentration. Aluminum dissolution by caustic leaching was identified as a treatment step to reduce the volume of remaining solids and prepare the tank for acid cleaning. Dissolution was performed in Tank 12 over a two month period in July and August, 2011. Sample results indicated that 16,440 kg of aluminum oxide (boehmite) had been dissolved representing 60% of the starting inventory. The evolution resulted in reducing the sludge solids volume by 22,300 liters (5900 gallons), preparing the tank for chemical cleaning with oxalic acid.

Dynamic modeling of sludge compaction and consolidation processes in wastewater secondary settling tanks

NARCIS (Netherlands)

Abusam, A.; Keesman, K.J.

2009-01-01

The double exponential settling model is the widely accepted model for wastewater secondary settling tanks. However, this model does not estimate accurately solids concentrations in the settler underflow stream, mainly because sludge compression and consolidation processes are not considered. In

Contaminant Leach Testing of Hanford Tank 241-C-104 Residual Waste

Energy Technology Data Exchange (ETDEWEB)

Cantrell, Kirk J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Snyder, Michelle M.V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-07-01

Leach testing of Tank C-104 residual waste was completed using batch and column experiments. Tank C-104 residual waste contains exceptionally high concentrations of uranium (i.e., as high as 115 mg/g or 11.5 wt.%). This study was conducted to provide data to develop contaminant release models for Tank C-104 residual waste and Tank C-104 residual waste that has been treated with lime to transform uranium in the waste to a highly insoluble calcium uranate (CaUO4) or similar phase. Three column leaching cases were investigated. In the first case, C-104 residual waste was leached with deionized water. In the second case, crushed grout was added to the column so that deionized water contacted the grout prior to contacting the waste. In the third case, lime was mixed in with the grout. Results of the column experiments demonstrate that addition of lime dramatically reduces the leachability of uranium from Tank C-104 residual waste. Initial indications suggest that CaUO4 or a similar highly insoluble calcium rich uranium phase forms as a result of the lime addition. Additional work is needed to definitively identify the uranium phases that occur in the as received waste and the waste after the lime treatment.

Final report for Tank 100 Sump sludge (KON332) for polychlorinated biphenyl's (PCB)

International Nuclear Information System (INIS)

Fuller, R.K.

1998-01-01

Final Report for Tank 100 Sump Sludge (KON332) for Polychlorinated Biphenyl's (PCB) Sample Receipt Sample KON332 was received from Tank 100-Sump (WESF) on May 18, 1998. The laboratory number issued for this sample is S98BOO0207 as shown on the Request for Sample Analysis (RSA) form (Attachment 4). The sample breakdown diagram (Attachment 3) provides a cross-reference of customer sample identification to the laboratory identification number. Attachment 4 provides copies of the Request for Sample Analysis (RSA) and Chain of Custody (COC) forms. The sample was received in the laboratory in a 125-ml polybottle. Breakdown and subsampling was performed on June 6, 1998. PCB analysis was performed on the wet sludge. A discussion of the results is presented in Attachment 2. The 222-S extraction bench sheets are presented in Attachment 5. The PCB raw data are presented in Attachment 6

Chemical characterization of SRP waste tank sludges and supernates

International Nuclear Information System (INIS)

Gray, L.W.; Donnan, M.Y.; Okamoto, B.Y.

1979-08-01

Most high-level liquid wastes at the Savannah River Plant (SRP) are byproducts from plutonium and enriched uranium recovery processes. The high-level liquid wastes generated by these separations processes are stored in large, underground, carbon-steel tanks. The liquid wastes consist of: supernate (an aqueous solution containing sodium, nitrate, nitrite, hydroxyl, and aluminate ions), sludge (a gelatinous material containing insoluble components of the waste, such as ferric and aluminum hydroxides, and mercuric and manganese oxides), and salt cake (crystals, such as sodium nitrate, formed by evaporation of water from supernate). Analyses of SRP wastes by laser-Raman spectrometry, atomic absorption spectrometry, spark-source mass spectrometry, neutron activation analysis, colorimetry, ion chromatography, and various other wet-chemical and radiochemical methods are discussed. These analyses are useful in studies of waste tank corrosion and of forms for long-term waste storage

SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 7A QUALIFICATION

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J.; Billings, A.; Click, D.

2011-07-08

Waste Solidification Engineering (WSE) has requested that characterization and a radioactive demonstration of the next batch of sludge slurry (Sludge Batch 7a*) be completed in the Shielded Cells Facility of the Savannah River National Laboratory (SRNL) via a Technical Task Request (TTR). This characterization and demonstration, or sludge batch qualification process, is required prior to transfer of the sludge from Tank 51 to the Defense Waste Processing Facility (DWPF) feed tank (Tank 40). The current WSE practice is to prepare sludge batches in Tank 51 by transferring sludge from other tanks. Discharges of nuclear materials from H Canyon are often added to Tank 51 during sludge batch preparation. The sludge is washed and transferred to Tank 40, the current DWPF feed tank. Prior to transfer of Tank 51 to Tank 40, SRNL simulates the Tank Farm and DWPF processes with a Tank 51 sample (referred to as the qualification sample). Sludge Batch 7a (SB7a) is composed of portions of Tanks 4, 7, and 12; the Sludge Batch 6 heel in Tank 51; and a plutonium stream from H Canyon. SRNL received the Tank 51 qualification sample (sample ID HTF-51-10-125) following sludge additions to Tank 51. This report documents: (1) The washing (addition of water to dilute the sludge supernate) and concentration (decanting of supernate) of the SB7a - Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF Chemical Process Cell (CPC) simulation using the washed Tank 51 sample. The simulation included a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid was added to the sludge to destroy nitrite and reduce mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit was added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters were based on work with a non

Basic and Acidic Leaching of Sludge from Melton Valley Storage Tank W-25

Energy Technology Data Exchange (ETDEWEB)

Collins, J.L., Egan, B.Z., Beahm, E.C., Chase, C.W., Anderson, K.K.

1997-10-01

Bench-scale leaching tests were conducted with samples of tank waste sludge from the Melton Valley Storage Tank (MVST) Facility at Oak Ridge National Laboratory (ORNL) to evaluate separation technology processes for use in concentrating the radionuclides and reducing the volume of waste for final disposal. This paper discusses the hot cell apparatus, the characterization of the sludge, the leaching methodology, and the results obtained from a variety of basic and acidic leaching tests of samples of sludge at ambient temperature. Basic leaching tests were also conducted at 75 and 95 deg C. The major alpha-,gamma., and beta-emitting radionuclides in the centrifuged, wet sludge solids were {sup 137}Cs, {sup 60}Co, {sup 154}Eu, {sup 241}Am, {sup 244}Cm {sup 90}Sr, Pu, U, and Th. The other major metals (in addition to the U and Th) and anions were Na, Ca, Al, K, Mg, NO{sub 3}{sup -},CO{sub 3}{sup 2-}, OH{sup -}, and O{sup 2-} organic carbon content was 3.0 +/- 1.0%. The pH was 13. A surprising result was that about 93% of the {sup 137}Cs in the centrifuged, wet sludge solids was bound in the solids and could not be solubilized by basic leaching at ambient temperature and 75 deg C. However, the solubility of the {sup 137}Cs was enhanced by heating the sludge to 95 deg C. In one of the tests,about 42% of the {sup 137}Cs was removed by leaching with 6.3 M NaOH at 95 deg C.Removing {sup 137}Cs from the W-25 sludge with nitric acid was a slow process. About 13% of the {sup 137}Cs was removed in 16 h with 3.0 M HNO{sub 3}. Only 22% of the {sup 137}Cs was removed in 117 h usi 6.0 M HNO{sub 3}. Successive leaching of sludge solids with 0.5 M, 3.0 M, 3.0 M; and 6.0 M HNO{sub 3} for a total mixing time of 558 h removed 84% of the {sup 137}Cs. The use of caustic leaching prior to HNO{sub 3} leaching, and the use of HF with HNO{sub 3} in acidic leaching, increased the rate of {sup 137}Cs dissolution. Gel formation proved to be one of the biggest problems associated with HNO{sub 3

Basic and Acidic Leaching of Sludge from Melton Valley Storage Tank W-25

International Nuclear Information System (INIS)

Collins, J.L.; Egan, B.Z.; Beahm, E.C.; Chase, C.W.; Anderson, K.K.

1997-10-01

Bench-scale leaching tests were conducted with samples of tank waste sludge from the Melton Valley Storage Tank (MVST) Facility at Oak Ridge National Laboratory (ORNL) to evaluate separation technology processes for use in concentrating the radionuclides and reducing the volume of waste for final disposal. This paper discusses the hot cell apparatus, the characterization of the sludge, the leaching methodology, and the results obtained from a variety of basic and acidic leaching tests of samples of sludge at ambient temperature. Basic leaching tests were also conducted at 75 and 95 deg C. The major alpha-,gamma., and beta-emitting radionuclides in the centrifuged, wet sludge solids were 137 Cs, 60 Co, 154 Eu, 241 Am, 244 Cm 90 Sr, Pu, U, and Th. The other major metals (in addition to the U and Th) and anions were Na, Ca, Al, K, Mg, NO 3 - ,CO 3 2- , OH - , and O 2- organic carbon content was 3.0 +/- 1.0%. The pH was 13. A surprising result was that about 93% of the 137 Cs in the centrifuged, wet sludge solids was bound in the solids and could not be solubilized by basic leaching at ambient temperature and 75 deg C. However, the solubility of the 137 Cs was enhanced by heating the sludge to 95 deg C. In one of the tests,about 42% of the 137 Cs was removed by leaching with 6.3 M NaOH at 95 deg C.Removing 137 Cs from the W-25 sludge with nitric acid was a slow process. About 13% of the 137 Cs was removed in 16 h with 3.0 M HNO 3 . Only 22% of the 137 Cs was removed in 117 h usi 6.0 M HNO 3 . Successive leaching of sludge solids with 0.5 M, 3.0 M, 3.0 M; and 6.0 M HNO 3 for a total mixing time of 558 h removed 84% of the 137 Cs. The use of caustic leaching prior to HNO 3 leaching, and the use of HF with HNO 3 in acidic leaching, increased the rate of 137 Cs dissolution. Gel formation proved to be one of the biggest problems associated with HNO 3 leaching of the W-25 sludge

Sludge Washing And Demonstration Of The DWPF Flowsheet In The SRNL Shielded Cells For Sludge Batch 8 Qualification

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J. M.; Crawford, C. L.

2013-04-26

The current Waste Solidification Engineering (WSE) practice is to prepare sludge batches in Tank 51 by transferring sludge from other tanks to Tank 51. Tank 51 sludge is washed and transferred to Tank 40, the current Defense Waste Processing Facility (DWPF) feed tank. Prior to transfer of Tank 51 to Tank 40, the Savannah River National Laboratory (SRNL) typically simulates the Tank Farm and DWPF processes using a Tank 51 sample (referred to as the qualification sample). WSE requested the SRNL to perform characterization on a Sludge Batch 8 (SB8) sample and demonstrate the DWPF flowsheet in the SRNL shielded cells for SB8 as the final qualification process required prior to SB8 transfer from Tank 51 to Tank 40. A 3-L sample from Tank 51 (the SB8 qualification sample; Tank Farm sample HTF-51-12-80) was received by SRNL on September 20, 2012. The as-received sample was characterized prior to being washed. The washed material was further characterized and used as the material for the DWPF process simulation including a Sludge Receipt and Adjustment Tank (SRAT) cycle, a Slurry Mix Evaporator (SME) cycle, and glass fabrication and chemical durability measurements.

Carbon-14 in sludge

International Nuclear Information System (INIS)

Fowler, J.R.; Coleman, C.J.

1983-01-01

The level of C-14 in high-level waste is needed to establish the amount of C-14 that will be released to the environment either as off-gas from the Defense Waste Processing Facility (DWPF) or as a component of saltstone. Available experimental data confirmed a low level of C-14 in soluble waste, but no data was available for sludge. Based on the processes used in each area, Purex LAW sludge in F-area and HM HAW sludge in H-area will contain the bulk of any sludge produced by the cladding. Accordingly, samples from Tank 8F containing Purex LAW and Tank 15H containing HM HAW were obtained and analyzed for C-14. These two waste types constitute approximately 70% of the total sludge inventory now stored in the waste tanks. Results from analyses of these two sludge types show: the total C-14 inventory in sludge now stored in the waste tanks is 6.8 Ci; C-14 releases to the atmosphere from the DWPF will average approximately 0.6 Ci annually at the projected sludge processing rate in the DWPF. 4 references, 2 tables

Removal of hydrocarbon from refinery tank bottom sludge employing microbial culture.

Science.gov (United States)

Saikia, Rashmi Rekha; Deka, Suresh

2013-12-01

Accumulation of oily sludge is becoming a serious environmental threat, and there has not been much work reported for the removal of hydrocarbon from refinery tank bottom sludge. Effort has been made in this study to investigate the removal of hydrocarbon from refinery sludge by isolated biosurfactant-producing Pseudomonas aeruginosa RS29 strain and explore the biosurfactant for its composition and stability. Laboratory investigation was carried out with this strain to observe its efficacy of removing hydrocarbon from refinery sludge employing whole bacterial culture and culture supernatant to various concentrations of sand-sludge mixture. Removal of hydrocarbon was recorded after 20 days. Analysis of the produced biosurfactant was carried out to get the idea about its stability and composition. The strain could remove up to 85 ± 3 and 55 ± 4.5 % of hydrocarbon from refinery sludge when whole bacterial culture and culture supernatant were used, respectively. Maximum surface tension reduction (26.3 mN m(-1)) was achieved with the strain in just 24 h of time. Emulsification index (E24) was recorded as 100 and 80 % with crude oil and n-hexadecane, respectively. The biosurfactant was confirmed as rhamnolipid containing C8 and C10 fatty acid components and having more mono-rhamnolipid congeners than the di-rhamnolipid ones. The biosurfactant was stable up to 121 °C, pH 2-10, and up to a salinity value of 2-10 % w/v. To our knowledge, this is the first report showing the potentiality of a native strain from the northeast region of India for the efficient removal of hydrocarbon from refinery sludge.

Biosynthesis of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) by bacterial community from propylene oxide saponification wastewater residual sludge.

Science.gov (United States)

Wang, Yiwei; Zhu, Ying; Gu, Pengfei; Li, Yumei; Fan, Xiangyu; Song, Dongxue; Ji, Yan; Li, Qiang

2017-05-01

The saponification wastewater from the process of propylene oxide (PO) production is contaminated with high chemical oxygen demand (COD) and chlorine contents. Although the activated sludge process could treat the PO saponification wastewater effectively, the residual sludge was difficult to be disposed properly. In this research, microbes in PO saponification wastewater residual sludge were acclimated to produce poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) from volatile fatty acids. Through Miseq Illumina highthroughput sequencing, the bacterial community discrepancy between the original and the acclimated sludge samples were analyzed. The proportions of Bacillus, Acinetobacter, Brevundimonas and Pseudomonas, the potential PHBV-producers in the residual sludge, were all obviously increased. In the batch fermentation, the production of PHBV could achieve 4.262g/L at 300min, with the content increased from 0.04% to 23.67% of mixed liquor suspended solid (MLSS) in the acclimated sludge, and the COD of the PO saponification wastewater was also decreased in the fermentation. This work would provide an effective solution for the utilization of PO saponification wastewater residual sludge. Copyright © 2017 Elsevier B.V. All rights reserved.

Criticality safety evaluation of disposing of K Basin sludge in double-shell tank AW-105

International Nuclear Information System (INIS)

ROGERS, C.A.

1999-01-01

A criticality safety evaluation is made of the disposal of K Basin sludge in double-shell tank (DST) AW-105 located in the 200 east area of Hanford Site. The technical basis is provided for limits and controls to be used in the development of a criticality prevention specification (CPS). A model of K Basin sludge is developed to account for fuel burnup. The iron/uranium mass ration required to ensure an acceptable magrin of subcriticality is determined

Waste sludge resuspension and transfer: development program

International Nuclear Information System (INIS)

Weeren, H.O.; Mackey, T.S.

1980-02-01

The six Gunite waste tanks at Oak Ridge National Laboratory (ORNL) contain about 400,000 gal of sludge that has precipitated from solution and settled during the 35 years these tanks have been in service. Eventual decommissioning of the tanks has been proposed. The first part of this program is to resuspend the accumulated sludge, to transfer it to new storage tanks in Melton Valley, and to dispose of it by the shale-fracturing process. On the basis of preliminary information, a tentative operational concept was adopted. The sludge in each tank would be resuspended by hydraulic sluicing and pumped from the tank. This resuspended sludge would be treated as necessary to keep the particles in suspension and would be pumped to the new waste-storage tanks. Subsequently the sludge would be pumped from the tanks, combined with a cement-base mix, and disposed of by the shale-fracturing facility. Verification of the feasibility of this concept required development effort on characterization of the sludge and development of techniques for resuspending the sludge and for keeping it in suspension. These development efforts are described in this report. Sections of the report describe both the known properties of the sludge and the tests of grinding methods investigated, discuss tests of various suspenders, describe tests with cement-base mixes, summarize hot-cell tests on actual sludge samples, and describe tests that were made at a mockup of a Gunite tank installation. On the basis of the tests made, it was concluded that reslurrying and resuspension of the sludge is quite feasible and that the suspensions can be made compatible with cement mixes

Fiscal year 1994 1/25-scale sludge mobilization testing

International Nuclear Information System (INIS)

Powell, M.R.; Gates, C.M.; Hymas, C.R.; Sprecher, M.A.; Morter, N.J.

1995-07-01

There are 28 one-million-gallon double-shell radioactive waste tanks on the Hanford Reservation in southeastern Washington State. The waste in these tanks was generated during processing of nuclear materials. Solids-laden slurries were placed into many of the tanks. Over time, the waste solids have settled to form a layer of sludge in the bottom of these tanks. The sludge layer thickness varies from tank to tank with some having only a few centimeters or no sludge up to some tanks which have about 4.5 m (15 ft) of sludge. It is planned that the waste will be removed from these tanks as part of the overall Hanford site cleanup efforts. Jet mixer pumps are to be placed into the tanks to stir up (mobilize) the sludge and form a uniform slurry suitable for pumping to downstream processing facilities. These mixer pumps use powerful jets of tank fluid directed horizontally out of two, diametrically opposed nozzles near the tank bottom. These fluid jets impinge upon the sludge and stir it up. The amount of sludge mobilized by the mixer pump jets depends not only on the jet properties, but also on the ability of the sludge to resist the jets. It is the goal of the work described in this document to develop the ability to predict how much sludge will be mobilized by the mixer pumps based on the size and velocity of the mixer pump jets and the physical and chemical properties of the tank sludge

TANK FARM CLOSURE - A NEW TWIST ON REGULATORY STRATEGIES FOR CLOSURE OF WASTE TANK RESIDUALS FOLLOWING NUREG

International Nuclear Information System (INIS)

LEHMAN LL

2008-01-01

Waste from a number of single-shell tanks (SST) at the U.S. Department of Energy's (DOE) Hanford Site has been retrieved by CH2M HILL Hanford Group to fulfill the requirements of the 'Hanford Federal Facility Agreement and Consent Order (HFFACO) [1]. Laboratory analyses of the Hanford tank residual wastes have provided concentration data which will be used to determine waste classification and disposal options for tank residuals. The closure of tank farm facilities remains one of the most challenging activities faced by the DOE. This is due in part to the complicated regulatory structures that have developed. These regulatory structures are different at each of the DOE sites, making it difficult to apply lessons learned from one site to the next. During the past two years with the passage of the Section 3116 of the 'Ronald Reagan Defense Authorization Act of 2005' (NDAA) [2] some standardization has emerged for Savannah River Site and the Idaho National Laboratory tank residuals. Recently, with the issuance of 'NRC Staff Guidance for Activities Related to US. Department of Energy Waste Determinations' (NUREG-1854) [3] more explicit options may be considered for Hanford tank residuals than are presently available under DOE Orders. NUREG-1854, issued in August 2007, contains several key pieces of information that if utilized by the DOE in the tank closure process, could simplify waste classification and streamline the NRC review process by providing information to the NRC in their preferred format. Other provisions of this NUREG allow different methods to be applied in determining when waste retrieval is complete by incorporating actual project costs and health risks into the calculation of 'technically and economically practical'. Additionally, the NUREG requires a strong understanding of the uncertainties of the analyses, which given the desire of some NRC/DOE staff may increase the likelihood of using probabilistic approaches to uncertainty analysis. The purpose

Radiological assessment of worker doses during sludge mobilization and removal at the Melton Valley storage tanks

International Nuclear Information System (INIS)

Kerr, G.D.; Coleman, R.L.; Kocher, D.C.; Wynn, C.C.

1996-01-01

This report presents an assessment of potential radiation doses to workers during mobilization and removal of contaminated sludges from the Melton Valley Storage Tanks at Oak Ridge National Laboratory. The assessment is based on (1) measurements of radionuclide concentrations in sludge and supernatant liquid samples from the waste storage tanks, (2) measurements of gamma radiation levels in various areas that will be accessed by workers during normal activities, (3) calculations of gamma radiation levels for particular exposure situations, especially when the available measurements are not applicable, and (4) assumed scenarios for worker activities in radiation areas. Only doses from external exposure are estimated in this assessment. Doses from internal exposure are assumed to be controlled by containment of radioactive materials or respiratory protection of workers and are not estimated

Effect of Antifoam Agent on Oxidative Leaching of Hanford Tank Sludge Simulants

International Nuclear Information System (INIS)

Rapko, Brian M.; Jones, Susan A.; Lumetta, Gregg J.; Peterson, Reid A.

2010-01-01

Oxidative leaching of simulant tank waste containing an antifoam agent (AFA) to reduce the chromium content of the sludge was tested using permanganate as the oxidant in 0.25 M NaOH solutions. AFA is added to the waste treatment process to prevent foaming. The AFA, Dow Corning Q2-3183A, is a surface-active polymer that consists of polypropylene glycol, polydimethylsiloxane, octylphenoxy polyethoxy ethanol, treated silica, and polyether polyol. Some of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) waste slurries contain high concentrations of undissolved solids that would exhibit undesirable behavior without AFA addition. These tests were conducted to determine the effect of the AFA on oxidative leaching of Cr(III) in waste by permanganate. It has not previously been determined what effect AFA has on the permanganate reaction. This study was conducted to determine the effect AFA has on the oxidation of the chromium, plus plutonium and other criticality-related elements, specifically Fe, Ni and Mn. During the oxidative leaching process, Mn is added as liquid permanganate solution and is converted to an insoluble solid that precipitates as MnO2 and becomes part of the solid waste. Caustic leaching was performed followed by an oxidative leach at either 25 C or 45 C. Samples of the leachate and solids were collected at each step of the process. Initially, Battelle-Pacific Northwest Division (PNWD) was contracted by Bechtel National, Inc. to perform these further scoping studies on oxidative alkaline leaching. The data obtained from the testing will be used by the WTP operations to develop procedures for permanganate dosing of Hanford tank sludge solids during oxidative leaching. Work was initially conducted under contract number 24590-101-TSA-W000-00004. In February 2007, the contract mechanism was switched to Pacific Northwest National Laboratory (PNNL) operating Contract DE-AC05-76RL01830. In summary, this report describes work focused on determining

Effect of Antifoam Agent on Oxidative Leaching of Hanford Tank Sludge Simulants

Energy Technology Data Exchange (ETDEWEB)

Rapko, Brian M.; Jones, Susan A.; Lumetta, Gregg J.; Peterson, Reid A.

2010-02-26

Oxidative leaching of simulant tank waste containing an antifoam agent (AFA) to reduce the chromium content of the sludge was tested using permanganate as the oxidant in 0.25 M NaOH solutions. AFA is added to the waste treatment process to prevent foaming. The AFA, Dow Corning Q2-3183A, is a surface-active polymer that consists of polypropylene glycol, polydimethylsiloxane, octylphenoxy polyethoxy ethanol, treated silica, and polyether polyol. Some of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) waste slurries contain high concentrations of undissolved solids that would exhibit undesirable behavior without AFA addition. These tests were conducted to determine the effect of the AFA on oxidative leaching of Cr(III) in waste by permanganate. It has not previously been determined what effect AFA has on the permanganate reaction. This study was conducted to determine the effect AFA has on the oxidation of the chromium, plus plutonium and other criticality-related elements, specifically Fe, Ni and Mn. During the oxidative leaching process, Mn is added as liquid permanganate solution and is converted to an insoluble solid that precipitates as MnO2 and becomes part of the solid waste. Caustic leaching was performed followed by an oxidative leach at either 25°C or 45°C. Samples of the leachate and solids were collected at each step of the process. Initially, Battelle-Pacific Northwest Division (PNWD) was contracted by Bechtel National, Inc. to perform these further scoping studies on oxidative alkaline leaching. The data obtained from the testing will be used by the WTP operations to develop procedures for permanganate dosing of Hanford tank sludge solids during oxidative leaching. Work was initially conducted under contract number 24590-101-TSA-W000-00004. In February 2007, the contract mechanism was switched to Pacific Northwest National Laboratory (PNNL) operating Contract DE-AC05-76RL01830. In summary, this report describes work focused on

Potential radiological exposure rates resulting from hypothetical dome failure at Tank W-10

International Nuclear Information System (INIS)

1994-07-01

The main plant area at Oak Ridge National Laboratory (ORNL) contains 12 buried Gunite tanks that were used for the storage and transfer of liquid radioactive waste. Although the tanks are no longer in use, they are known to contain some residual contaminated sludges and liquids. In the event of an accidental tank dome failure, however unlikely, the liquids, sludges, and radioactive contaminants within the tank walls themselves could create radiation fields and result in above-background exposures to workers nearby. This Technical Memorandum documents a series of calculations to estimate potential radiological exposure rates and total exposures to workers in the event of a hypothetical collapse of a Gunite tank dome. Calculations were performed specifically for tank W-10 because it contains the largest radioactivity inventory (approximately half of the total activity) of all the Gunite tanks. These calculations focus only on external, direct gamma exposures for prescribed, hypothetical exposure scenarios and do not address other possible tank failure modes or routes of exposure. The calculations were performed with established, point-kernel gamma ray modeling codes

Potential radiological exposure rates resulting from hypothetical dome failure at Tank W-10

Energy Technology Data Exchange (ETDEWEB)

1994-07-01

The main plant area at Oak Ridge National Laboratory (ORNL) contains 12 buried Gunite tanks that were used for the storage and transfer of liquid radioactive waste. Although the tanks are no longer in use, they are known to contain some residual contaminated sludges and liquids. In the event of an accidental tank dome failure, however unlikely, the liquids, sludges, and radioactive contaminants within the tank walls themselves could create radiation fields and result in above-background exposures to workers nearby. This Technical Memorandum documents a series of calculations to estimate potential radiological exposure rates and total exposures to workers in the event of a hypothetical collapse of a Gunite tank dome. Calculations were performed specifically for tank W-10 because it contains the largest radioactivity inventory (approximately half of the total activity) of all the Gunite tanks. These calculations focus only on external, direct gamma exposures for prescribed, hypothetical exposure scenarios and do not address other possible tank failure modes or routes of exposure. The calculations were performed with established, point-kernel gamma ray modeling codes.

Ultrasonic reduction of excess sludge from the activated sludge system

International Nuclear Information System (INIS)

Zhang Guangming; Zhang Panyue; Yang Jinmei; Chen Yanming

2007-01-01

Sludge treatment has long become the most challenging problem in wastewater treatment plants. Previous studies showed that ozone or chlorine effectively liquefies sludge into substrates for bio-degradation in the aeration tank, and thus reduces the excess sludge. This paper employs ultrasound to reduce the excess sludge from the sequential batch reactor (SBR) system. Partial sludge was disintegrated into dissolved substrates by ultrasound in an external sono-tank and was then returned to the SBR for bio-degradation. The results showed that ultrasound (25 kHz) effectively liquefied the sludge. The most effective conditions for sludge reduction were as following: sludge sonication ratio of 3/14, ultrasound intensity of 120 kW/kgDS, and sonication duration of 15 min. The amount of excess sludge was reduced by 91.1% to 17.8 mg/(L d); the organic content and settleability of sludge in the SBR were not impacted. The chemical oxygen demand (COD) removal efficiency was 81.1%, the total nitrogen (TN) removal efficiency was 17-66%, and high phosphorus concentration in the effluent was observed

SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 5 QUALIFICATION

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J; Cj Bannochie, C; Damon Click, D; Dan Lambert, D; Michael Stone, M; Bradley Pickenheim, B; Amanda Billings, A; Ned Bibler, N

2008-11-10

Sludge Batch 5 (SB5) is predominantly a combination of H-modified (HM) sludge from Tank 11 that underwent aluminum dissolution in late 2007 to reduce the total mass of sludge solids and aluminum being fed to the Defense Waste Processing Facility (DWPF) and Purex sludge transferred from Tank 7. Following aluminum dissolution, the addition of Tank 7 sludge and excess Pu to Tank 51, Liquid Waste Operations (LWO) provided the Savannah River National Laboratory (SRNL) a 3-L sample of Tank 51 sludge for SB5 qualification. SB5 qualification included washing the sample per LWO plans/projections (including the addition of a Pu/Be stream from H Canyon), DWPF Chemical Process Cell (CPC) simulations, waste glass fabrication (vitrification), and waste glass chemical durability evaluation. This report documents: (1) The washing (addition of water to dilute the sludge supernatant) and concentration (decanting of supernatant) of the Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF CPC simulation using the washed Tank 51 sample. This includes a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid is added to the sludge to destroy nitrite and remove mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit is added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters for the CPC processing were based on work with a non radioactive simulant. (3) Vitrification of a portion of the SME product and Product Consistency Test (PCT) evaluation of the resulting glass. (4) Rheology measurements of the initial slurry samples and samples after each phase of CPC processing. This work is controlled by a Task Technical and Quality Assurance Plan (TTQAP) , and analyses are guided by an Analytical Study Plan. This work is Technical Baseline Research and Development (R

Bench-scale cross flow filtration of Tank S-107 sludge slurries and Tank C-107 supernatant

International Nuclear Information System (INIS)

Geeting, J.G.H.; Reynolds, B.A.

1996-10-01

Hanford tank waste filtration experiments were conducted using a bench-scale cross flow filter on 8 wt%, 1.5 wt%, and 0.05 wt% Tank S- 107 sludge slurries and on Tank C-107 supernatant. For comparison, two simulants each with solids loadings of 8 wt% and 0.05 wt% were also tested. The purpose of the tests was to determine the efficacy of cross flow filtration on slurries of various solids loadings. -In addition, filtrate flux dependency on axial velocity and transmembrane pressure was sought so that conditions for future experiments might be better selected. The data gathered are compared to the simulants and three cross flow filtration models. A two- parameter central composite design which tested. transmembrane pressure from 5 to 40 psig and axial Velocity from 3 to 9 ft/s was used for all feeds. The cross flow filter effectively removed solids from the liquid, as 19 of 20 filtrate samples had particle concentrations below the resolution limit of the photon correlation spectrometer used in the Hanford Radiocolloid Laboratory. Radiochemical analysis indicate that all filtrate samples were below Class A waste classification standards for 9OSr and transuranics

The reduction of oil pollutants of petroleum products storage-tanks sludge using low-cost adsorbents

Directory of Open Access Journals (Sweden)

Mokhtari-Hosseini Zahra Beagom

2017-01-01

Full Text Available Disposal of storage tank sludge in oil depots is a major environmental concern due to the high concentration of hydrocarbons involved. This paper investigates the reduction of the sludge oil pollutants with initial oil and grease concentration of about 50 mass% using low cost adsorbents. Among the examined adsorbents, sawdust indicated the maximum removal of oil and grease. The screening and optimizing of process parameters were evaluated employing Plackett-Burman design and response surface method. For the optimized conditions, more than 60 mass% of oil and grease from the sludge was removed. Moreover, it was found that sawdust adsorption of the oil and grease approximately followed the Freundlich isotherm. The results indicated that oil pollutants of sludge could be reduced using sawdust as a low-cost, available and flammable adsorbent so that thus saturated adsorbents could be used as fuel in certain industries.

Revised cost savings estimate with uncertainty for enhanced sludge washing of underground storage tank waste

International Nuclear Information System (INIS)

DeMuth, S.

1998-01-01

Enhanced Sludge Washing (ESW) has been selected to reduce the amount of sludge-based underground storage tank (UST) high-level waste at the Hanford site. During the past several years, studies have been conducted to determine the cost savings derived from the implementation of ESW. The tank waste inventory and ESW performance continues to be revised as characterization and development efforts advance. This study provides a new cost savings estimate based upon the most recent inventory and ESW performance revisions, and includes an estimate of the associated cost uncertainty. Whereas the author's previous cost savings estimates for ESW were compared against no sludge washing, this study assumes the baseline to be simple water washing which more accurately reflects the retrieval activity along. The revised ESW cost savings estimate for all UST waste at Hanford is $6.1 B ± $1.3 B within 95% confidence. This is based upon capital and operating cost savings, but does not include development costs. The development costs are assumed negligible since they should be at least an order of magnitude less than the savings. The overall cost savings uncertainty was derived from process performance uncertainties and baseline remediation cost uncertainties, as determined by the author's engineering judgment

Improving material and energy recovery from the sewage sludge and biomass residues

International Nuclear Information System (INIS)

Kliopova, Irina; Makarskienė, Kristina

2015-01-01

Highlights: • SRF production from 10–40 mm fraction of pre-composted sludge and biomass residues. • The material and energy balance of compost and SRF production. • Characteristics of raw materials and classification of produced SRF. • Results of the efficiency of energy recovery, comparison analysis with – sawdust. - Abstract: Sewage sludge management is a big problem all over the world because of its large quantities and harmful impact on the environment. Energy conversion through fermentation, compost production from treated sludge for agriculture, especially for growing energetic plants, and treated sludge use for soil remediation are widely used alternatives of sewage sludge management. Recently, in many EU countries the popularity of these methods has decreased due to the sewage sludge content (heavy metals, organic pollutions and other hazards materials). This paper presents research results where the possibility of solid recovered fuel (SRF) production from the separate fraction (10–40 mm) of pre-composted materials – sewage sludge from municipal waste water treatment plant and biomass residues has been evaluated. The remaining fractions of pre-composted materials can be successfully used for compost or fertiliser production, as the concentration of heavy metals in the analysed composition is reduced in comparison with sewage sludge. During the experiment presented in this paper the volume of analysed biodegradable waste was reduced by 96%: about 20% of input biodegradable waste was recovered to SRF in the form of pellets with 14.25 MJ kg −1 of the net calorific value, about 23% were composted, the rest – evaporated and discharged in a wastewater. The methods of material-energy balances and comparison analysis of experiment data have been chosen for the environmental impact assessment of this biodegradable waste management alternative. Results of the efficiency of energy recovery from sewage sludge by SRF production and burning

Improving material and energy recovery from the sewage sludge and biomass residues

Energy Technology Data Exchange (ETDEWEB)

Kliopova, Irina, E-mail: irina.kliopova@ktu.lt; Makarskienė, Kristina

2015-02-15

Highlights: • SRF production from 10–40 mm fraction of pre-composted sludge and biomass residues. • The material and energy balance of compost and SRF production. • Characteristics of raw materials and classification of produced SRF. • Results of the efficiency of energy recovery, comparison analysis with – sawdust. - Abstract: Sewage sludge management is a big problem all over the world because of its large quantities and harmful impact on the environment. Energy conversion through fermentation, compost production from treated sludge for agriculture, especially for growing energetic plants, and treated sludge use for soil remediation are widely used alternatives of sewage sludge management. Recently, in many EU countries the popularity of these methods has decreased due to the sewage sludge content (heavy metals, organic pollutions and other hazards materials). This paper presents research results where the possibility of solid recovered fuel (SRF) production from the separate fraction (10–40 mm) of pre-composted materials – sewage sludge from municipal waste water treatment plant and biomass residues has been evaluated. The remaining fractions of pre-composted materials can be successfully used for compost or fertiliser production, as the concentration of heavy metals in the analysed composition is reduced in comparison with sewage sludge. During the experiment presented in this paper the volume of analysed biodegradable waste was reduced by 96%: about 20% of input biodegradable waste was recovered to SRF in the form of pellets with 14.25 MJ kg{sup −1} of the net calorific value, about 23% were composted, the rest – evaporated and discharged in a wastewater. The methods of material-energy balances and comparison analysis of experiment data have been chosen for the environmental impact assessment of this biodegradable waste management alternative. Results of the efficiency of energy recovery from sewage sludge by SRF production and burning

Characterization of the heterotrophic biomass and the endogenous residue of activated sludge.

Science.gov (United States)

Ramdani, Abdellah; Dold, Peter; Gadbois, Alain; Déléris, Stéphane; Houweling, Dwight; Comeau, Yves

2012-03-01

The activated sludge process generates an endogenous residue (X(E)) as a result of heterotrophic biomass decay (X(H)). A literature review yielded limited information on the differences between X(E) and X(H) in terms of chemical composition and content of extracellular polymeric substances (EPS). The objective of this project was to characterize the chemical composition (x, y, z, a, b and c in C(x)H(y)O(z)N(a)P(b)S(c)) of the endogenous and the active fractions and EPS of activated sludge from well designed experiments. To isolate X(H) and X(E) in this study, activated sludge was generated in a 200L pilot-scale aerobic membrane bioreactor (MBR) fed with a soluble and completely biodegradable synthetic influent of sodium acetate as the sole carbon source. This influent, which contained no influent unbiodegradable organic or inorganic particulate matter, allowed the generation of a sludge composed essentially of two fractions: heterotrophic biomass X(H) and an endogenous residue X(E), the nitrifying biomass being negligible. The endogenous decay rate and the active biomass fraction of the MBR sludge were determined in 21-day aerobic digestion batch tests by monitoring the VSS and OUR responses. Fractions of X(H) and X(E) were respectively 68% and 32% in run 1 (MBR at 5.2 day SRT) and 59% and 41% in run 2 (MBR at 10.4 day SRT). The endogenous residue was isolated by subjecting the MBR sludge to prolonged aerobic batch digestion for 3 weeks, and was characterized in terms of (a) elemental analysis for carbon, nitrogen, phosphorus and sulphur; and (b) content of EPS. The MBR sludge was characterized using the same procedures (a and b). Knowing the proportions of X(H) and X(E) in this sludge, it was possible to characterize X(H) by back calculation. Results from this investigation showed that the endogenous residue had a chemical composition different from that of the active biomass with a lower content of inorganic matter (1:4.2), of nitrogen (1:2.9), of phosphorus (1

Alternative Chemical Cleaning Methods for High Level Waste Tanks: Simulant Studies

Energy Technology Data Exchange (ETDEWEB)

Rudisill, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); King, W. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hay, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Jones, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-11-19

Solubility testing with simulated High Level Waste tank heel solids has been conducted in order to evaluate two alternative chemical cleaning technologies for the dissolution of sludge residuals remaining in the tanks after the exhaustion of mechanical cleaning and sludge washing efforts. Tests were conducted with non-radioactive pure phase metal reagents, binary mixtures of reagents, and a Savannah River Site PUREX heel simulant to determine the effectiveness of an optimized, dilute oxalic/nitric acid cleaning reagent and pure, dilute nitric acid toward dissolving the bulk non-radioactive waste components. A focus of this testing was on minimization of oxalic acid additions during tank cleaning. For comparison purposes, separate samples were also contacted with pure, concentrated oxalic acid which is the current baseline chemical cleaning reagent. In a separate study, solubility tests were conducted with radioactive tank heel simulants using acidic and caustic permanganate-based methods focused on the “targeted” dissolution of actinide species known to be drivers for Savannah River Site tank closure Performance Assessments. Permanganate-based cleaning methods were evaluated prior to and after oxalic acid contact.

ANALYSIS OF SAMPLES FROM TANK 5F CHEMICAL CLEANING

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.; Fink, S.

2011-03-07

The Savannah River Site (SRS) is preparing Tank 5F for closure. The first step in preparing the tank for closure is mechanical sludge removal. Following mechanical sludge removal, SRS performed chemical cleaning with oxalic acid to remove the sludge heel. Personnel are currently assessing the effectiveness of the chemical cleaning. SRS personnel collected liquid samples during chemical cleaning and submitted them to Savannah River National Laboratory (SRNL) for analysis. Following chemical cleaning, they collected a solid sample (also known as 'process sample') and submitted it to SRNL for analysis. The authors analyzed these samples to assess the effectiveness of the chemical cleaning process. The conclusions from this work are: (1) With the exception of iron, the dissolution of sludge components from Tank 5F agreed with results from the actual waste demonstration performed in 2007. The fraction of iron removed from Tank 5F by chemical cleaning was significantly less than the fraction removed in the SRNL demonstrations. The likely cause of this difference is the high pH following the first oxalic acid strike. (2) Most of the sludge mass remaining in the tank is iron and nickel. (3) The remaining sludge contains approximately 26 kg of barium, 37 kg of chromium, and 37 kg of mercury. (4) Most of the radioactivity remaining in the residual material is beta emitters and {sup 90}Sr. (5) The chemical cleaning removed more than {approx} 90% of the uranium isotopes and {sup 137}Cs. (6) The chemical cleaning removed {approx} 70% of the neptunium, {approx} 83% of the {sup 90}Sr, and {approx} 21% of the {sup 60}Co. (7) The chemical cleaning removed less than 10% of the plutonium, americium, and curium isotopes. (8) The chemical cleaning removed more than 90% of the aluminium, calcium, and sodium from the tank. (9) The cleaning operations removed 61% of lithium, 88% of non-radioactive strontium, and 65% of zirconium. The {sup 90}Sr and non-radioactive strontium were

Radioactive air emissions notice of construction 340-A building tank sludge clean out

International Nuclear Information System (INIS)

Hays, C.B.

1997-01-01

This document serves as a notice of construction pursuant to the requirements of Washington Administrative Code (WAC) 246-247-060 and as a request for approval to construct pursuant to 40 Code of Federal Regulations (CFR) 61.96 for the removal of sludge from six storage tanks located inside the 340-A Building, which is located in the 300 Area of the Hanford Site

CHEMICAL DIFFERENCES BETWEEN SLUDGE SOLIDS AT THE F AND H AREA TANK FARMS

Energy Technology Data Exchange (ETDEWEB)

Reboul, S.

2012-08-29

and HTF samples indicated that the primary crystalline compounds of iron in sludge solids are Fe{sub 2}O{sub 3}, Fe{sub 3}O{sub 4}, and FeO(OH), and the primary crystalline compounds of aluminum are Al(OH){sub 3} and AlO(OH). Also identified were carbonate compounds of calcium, magnesium, and sodium; a nitrated sodium aluminosilicate; and various uranium compounds. Consistent with expectations, oxalate compounds were identified in solids associated with oxalic acid cleaning operations. The most likely oxidation states and chemical forms of technetium are assessed in the context of solubility, since technetium-99 is a key risk driver from an environmental fate and transport perspective. The primary oxidation state of technetium in SRS sludge solids is expected to be Tc(IV). In salt waste, the primary oxidation state is expected to be Tc(VII). The primary form of technetium in sludge is expected to be a hydrated technetium dioxide, TcO{sub 2} {center_dot} xH{sub 2}O, which is relatively insoluble and likely co-precipitated with iron. In salt waste solutions, the primary form of technetium is expected to be the very soluble pertechnetate anion, TcO{sub 4}{sup -}. The relative differences between the F and H Tank Farm waste provide a basis for anticipating differences that will occur as constituents of FTF and HTF waste residue enter the environment over the long-term future. If a constituent is significantly more dominant in one of the Tank Farms, its long-term environmental contribution will likely be commensurately higher, assuming the environmental transport conditions of the two Tank Farms share some commonality. It is in this vein that the information cited in this document is provided - for use during the generation, assessment, and validation of Performance Assessment modeling results.

Radioactivity in sludge: tank cleaning procedures and sludge disposal

International Nuclear Information System (INIS)

Bradley, D.A.

1995-01-01

In the oil and gas industry management of alpha-active sludge is made more complex by the presence of hydrocarbons and heavy metals. This presentation discusses the origin of radioactivity in sludge, management of risk in terms of safe working procedures, storage and possible disposal options. The several options will generally involve aspects of dilution or of concentration; issues to be discussed will include sludge farming, bioremediation and incineration. (author)

Lipid profiling in sewage sludge.

Science.gov (United States)

Zhu, Fenfen; Wu, Xuemin; Zhao, Luyao; Liu, Xiaohui; Qi, Juanjuan; Wang, Xueying; Wang, Jiawei

2017-06-01

High value-added reutilization of sewage sludge from wastewater treatment plants (WWTPs) is essential in sustainable development in WWTPs. However, despite the advantage of high value reutilization, this process must be based on a detailed study of organics in sludge. We used the methods employed in life sciences to determine the profile of lipids (cellular lipids, free fatty acids (FFAs), and wax/gum) in five sludge samples obtained from three typical WWTPs in Beijing; these samples include one sludge sample from a primary sedimentation tank, two activated sludge samples from two Anaerobic-Anoxic-Oxic (A2/O) tanks, and two activated sludge samples from two membrane bioreactor tanks. The percentage of total raw lipids varied from 2.90% to 12.3%. Sludge from the primary sedimentation tank showed the highest concentrations of lipid, FFA, and wax/gum and the second highest concentration of cellular lipids. All activated sludge contained an abundance of cellular lipids (>54%). Cells in sludge can from plants, animals, microbes and so on in wastewater. Approximately 14 species of cellular lipids were identified, including considerable high value-potential ceramide (9567-38774 mg/kg), coenzyme (937-3897 mg/kg), and some phosphatidylcholine (75-548 mg/kg). The presence of those lipid constituents would thus require a wider range of recovery methods for sludge. Both cellular lipids and FFAs contain an abundance of C16-C18 lipids at high saturation level, and they serve as good resources for biodiesel production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of hydrated lime on radionuclides stabilization of Hanford tank residual waste.

Science.gov (United States)

Wang, Guohui; Um, Wooyong; Cantrell, Kirk J; Snyder, Michelle M V; Bowden, Mark E; Triplett, Mark B; Buck, Edgar C

2017-10-01

Chemical stabilization of tank residual waste is part of a Hanford Site tank closure strategy to reduce overall risk levels to human health and the environment. In this study, a set of column leaching experiments using tank C-104 residual waste were conducted to evaluate the leachability of uranium (U) and technetium (Tc) where grout and hydrated lime were applied as chemical stabilizing agents. The experiments were designed to simulate future scenarios where meteoric water infiltrates through the vadose zones into the interior of the tank filled with layers of grout or hydrated lime, and then contacts the residual waste. Effluent concentrations of U and Tc were monitored and compared among three different packing columns (waste only, waste + grout, and waste + grout + hydrated lime). Geochemical modeling of the effluent compositions was conducted to determine saturation indices of uranium solid phases that could control the solubility of uranium. The results indicate that addition of hydrated lime strongly stabilized the uranium through transforming uranium to a highly insoluble calcium uranate (CaUO 4 ) or similar phase, whereas no significant stabilization effect of grout or hydrated lime was observed on Tc leachability. The result implies that hydrated lime could be a great candidate for stabilizing Hanford tank residual wastes where uranium is one of the main concerns. Published by Elsevier Ltd.

Exploratory tests of washing radioactive sludge samples from the Melton Valley and evaporator facility storage tanks at ORNL

International Nuclear Information System (INIS)

Sears, M.B.; Botts, J.L.; Keller, J.M.

1991-09-01

Exploratory tests were initiated to wash radioactive sludge samples from the waste storage tanks at the Oak Ridge National Laboratory (ORNL). The purpose was to provide preliminary information about (1) the anions in the sludge phase that are soluble in water or dilute acid (e.g., the anions in the interstitial liquid) and (2) the solubilities of sludge constituents in water under process conditions. The experiments were terminated before completion due to changing priorities by the Department of Energy (DOE). This memorandum was prepared primarily for documentation purposes and presents the incomplete data. 3 refs., 13 tabs

FY 1999 cold demonstration of the Multi-Point Injection (MPI) process for stabilizing contaminated sludge in buried horizontal tanks with limited access at the Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Kauschinger, J.L.; Lewis, B.E.; Spence, R.D.

2000-01-01

A major problem faced by the U.S. Department of Energy is the remediation of buried tank waste. Exhumation of the sludge is currently the preferred remediation method. However, exhumation does not typically remove all the contaminated material from the tank. The best management practices for in-tank treatment of wastes require an integrated approach to develop appropriate treatment agents that can be safely delivered and uniformly mixed with the sludge. Ground Environmental Services, Inc., has developed and demonstrated a remotely controlled, high-velocity, jet-delivery system, which is termed Multi-Point-Injection (MPItrademark). This robust jet-delivery system has been used to create homogeneous monoliths containing shallow-buried miscellaneous waste in trenches [fiscal year (FY) 1995] and surrogate sludge in a cylindrical test tank (FY 1998). During the FY 1998 demonstration, the MPI process was able to successfully form a 32-ton uniform monolith in about 8 min. Analytical data indicated that 10 tons of a zeolite-type physical surrogate were uniformly mixed within the 40-inch-thick monolith without lifting the MPI jetting tools off the tank floor. Over 1,000 lb of cohesive surrogates, with consistencies of Gunite and Associated Tanks (GAATs) TH-4 and Hanford tank sludges, were easily mixed into the monolith without exceeding a core temperature of 100 F during curing

Process Development for Permanganate Addition During Oxidative Leaching of Hanford Tanks Sludges

International Nuclear Information System (INIS)

Rapko, Brian M.; Lumetta, Gregg J.; Deschane, Jaquetta R.; Peterson, Reid A.; Blanchard, David L.

2007-01-01

Previous Bechtel National, Incorporated (BNI)-sponsored studies have targeted optimizing sodium permanganate for the selective oxidation of chromium from washed Hanford tank sludges (Rapko et al. 2004; Rapko et al. 2005). The recommendation from previous work was that contact with sodium permanganate in a minimally caustic solution, i.e., 0.1 to 0.25 M [OH-] initially, provided maximum Cr dissolution while minimizing concomitant Pu dissolution. At the request of BNI, further work on oxidative alkaline leaching was performed

Performance of a system with full- and pilot-scale sludge drying reed bed units treating septic tank sludge in Brazil.

Science.gov (United States)

Calderón-Vallejo, Luisa Fernanda; Andrade, Cynthia Franco; Manjate, Elias Sete; Madera-Parra, Carlos Arturo; von Sperling, Marcos

2015-01-01

This study investigated the performance of sludge drying reed beds (SDRB) at full- and pilot-scale treating sludge from septic tanks in the city of Belo Horizonte, Brazil. The treatment units, planted with Cynodon spp., were based on an adaptation of the first-stage of the French vertical-flow constructed wetland, originally developed for treating sewage. Two different operational phases were investigated; in the first one, the full-scale unit was used together with six pilot-scale columns in order to test different feeding strategies. For the second phase, only the full-scale unit was used, including a recirculation of the filtered effluent (percolate) to one of the units of the French vertical wetland. Sludge application was done once a week emptying a full truck, during 25 weeks. The sludge was predominantly diluted, leading to low solids loading rates (median values of 18 kgTS m(-2) year(-1)). Chemical oxygen demand removal efficiency in the full-scale unit was reasonable (median of 71%), but the total solids removal was only moderate (median of 44%) in the full-scale unit without recirculation. Recirculation did not bring substantial improvements in the overall performance. The other loading conditions implemented in the pilot columns also did not show statistically different performances.

TEMPEST code modifications and testing for erosion-resisting sludge simulations

International Nuclear Information System (INIS)

Onishi, Y.; Trent, D.S.

1998-01-01

The TEMPEST computer code has been used to address many waste retrieval operational and safety questions regarding waste mobilization, mixing, and gas retention. Because the amount of sludge retrieved from the tank is directly related to the sludge yield strength and the shear stress acting upon it, it is important to incorporate the sludge yield strength into simulations of erosion-resisting tank waste retrieval operations. This report describes current efforts to modify the TEMPEST code to simulate pump jet mixing of erosion-resisting tank wastes and the models used to test for erosion of waste sludge with yield strength. Test results for solid deposition and diluent/slurry jet injection into sludge layers in simplified tank conditions show that the modified TEMPEST code has a basic ability to simulate both the mobility and immobility of the sludges with yield strength. Further testing, modification, calibration, and verification of the sludge mobilization/immobilization model are planned using erosion data as they apply to waste tank sludges

Overall effect of carbon production and nutrient release in sludge holding tank on mainstream biological nutrient removal efficiency.

Science.gov (United States)

Jabari, Pouria; Yuan, Qiuyan; Oleszkiewicz, Jan A

2017-09-11

The potential of hydrolysis/fermentation of activated sludge in sludge holding tank (SHT) to produce additional carbon for the biological nutrient removal (BNR) process was investigated. The study was conducted in anaerobic batch tests using the BNR sludge (from a full-scale Westside process) and the mixture of BNR sludge with conventional non-BNR activated sludge (to have higher biodegradable particulate chemical oxygen demand (bpCOD) in sludge). The BioWin 4.1 was used to simulate the anaerobic batch test of the BNR sludge. Also, the overall effect of FCOD production and nutrient release on BNR efficiency of the Westside process was estimated. The experimental results showed that the phosphorous uptake of sludge increased during hydrolysis/ fermentation condition up to the point when poly-P was completely utilized; afterwards, it decreased significantly. The BioWin simulation could not predict the loss of aerobic phosphorous uptake after poly-P was depleted. The results showed that in the case of activated sludge with relatively higher bpCOD (originating from plants with short sludge retention time or without primary sedimentation), beneficial effect of SHT on BNR performance is feasible. In order to increase the potential of SHT to enhance BNR efficiency, a relatively low retention time and high sludge load is recommended.

The role and control of sludge age in biological nutrient removal activated sludge systems.

Science.gov (United States)

Ekama, G A

2010-01-01

The sludge age is the most fundamental and important parameter in the design, operation and control of biological nutrient removal (BNR) activated sludge (AS) systems. Generally, the better the effluent and waste sludge quality required from the system, the longer the sludge age, the larger the biological reactor and the more wastewater characteristics need to be known. Controlling the reactor concentration does not control sludge age, only the mass of sludge in the system. When nitrification is a requirement, sludge age control becomes a requirement and the secondary settling tanks can no longer serve the dual purpose of clarifier and waste activated sludge thickeners. The easiest and most practical way to control sludge age is with hydraulic control by wasting a defined proportion of the reactor volume daily. In AS plants with reactor concentration control, nitrification fails first. With hydraulic control of sludge age, nitrification will not fail, rather the plant fails by shedding solids over the secondary settling tank effluent weirs.

Stabilization of in-tank residual wastes and external tank soil contamination for the Hanford tank closure program: application to the AX tank farm

Energy Technology Data Exchange (ETDEWEB)

SONNICHSEN, J.C.

1998-10-12

Mixed high-level waste is currently stored in underground tanks at the US Department of Energy's (DOE's) Hanford Site. The plan is to retrieve the waste, process the water, and dispose of the waste in a manner that will provide less long-term health risk. The AX Tank Farm has been identified for purposes of demonstration. Not all the waste can be retrieved from the tanks and some waste has leaked from these tanks into the underlying soil. Retrieval of this waste could result in additional leakage. During FY1998, the Sandia National Laboratory was under contract to evaluate concepts for immobilizing the residual waste remaining in tanks and mitigating the migration of contaminants that exist in the soil column. Specifically, the scope of this evaluation included: development of a layered tank fill design for reducing water infiltration; development of in-tank getter technology; mitigation of soil contamination through grouting; sequestering of specific radionuclides in soil; and geochemical and hydrologic modeling of waste-water-soil interactions. A copy of the final report prepared by Sandia National Laboratory is attached.

Hydrogen Evolution and Sludge Suspension During the Preparation of the First Batch of Sludge at the Savannah River Site

International Nuclear Information System (INIS)

Hay, M.S.; Lee, E.D.

1995-01-01

The first batch of High Level Radioactive Sludge for the Defense Waste Processing Facility is being prepared in two 4.9 million liter waste tanks. The preparation involves removing water soluble salts by washing (water addition, sludge suspension, settling and decantation). Sludge suspension is accomplished using long shafted slurry pumps that are mounted on rotating turntables. During the sludge suspension runs in 1993 and 1994, the slurry pumps' cleaning radius was determined to be less than that expected from previous determinations using synthetic sludge in a full size waste tank mockup. Hydrogen concentrations in the tanks' vapor space were monitored during the sludge suspension activities. As expected, the initial agitation of the sludge increased the hydrogen concentration, however, with the controls in place the hydrogen concentration was maintained below seven percent of the lower flammability limit

Contaminant Release from Residual Waste in Single Shell Tanks at the Hanford Site, Washington, USA - 9276

International Nuclear Information System (INIS)

Cantrell, Kirk J.; Krupka, Kenneth M.; Deutsch, William J.; Lindberg, Michael J.

2009-01-01

Determinations of elemental and solid-phase compositions, and contaminant release studies have been applied in an ongoing study of residual tank wastes (i.e., waste remaining after final retrieval operations) from five of 149 underground single-shell storage tanks (241-C-103, 241-C-106, 241-C-202, 241-C-203, and 241-S-112) at the U.S. Department of Energy's Hanford Site in Washington State. This work is being conducted to support performance assessments that will be required to evaluate long-term health and safety risks associated with tank site closure. The results of studies completed to date show significant variability in the compositions, solid phase properties, and contaminant release characteristics from these residual tank wastes. This variability is the result of differences in waste chemistry/composition of wastes produced from several different spent fuel reprocessing schemes, subsequent waste reprocessing to remove certain target constituents, tank farm operations that concentrated wastes and mixed wastes between tanks, and differences in retrieval processes used to remove the wastes from the tanks. Release models were developed based upon results of chemical characterization of the bulk residual waste, solid-phase characterization (see companion paper 9277 by Krupka et al.), leaching and extraction experiments, and geochemical modeling. In most cases empirical release models were required to describe contaminant release from these wastes. Release of contaminants from residual waste was frequently found to be controlled by the solubility of phases that could not be identified and/or for which thermodynamic data and/or dissolution rates have not been measured. For example, significant fractions of Tc-99, I-129, and Cr appear to be coprecipitated at trace concentrations in metal oxide phases that could not be identified unambiguously. In the case of U release from tank 241-C-103 residual waste, geochemical calculations indicated that leachate

Concentrations and environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks and accumulation in sludge, New Jersey Coastal Plain, USA

Science.gov (United States)

Szabo, Z.; Jacobsen, E.; Kraemer, T.F.; Parsa, B.

2008-01-01

Concentrations of Ra in liquid and solid wastes generated from 15 softeners treating domestic well waters from New Jersey Coastal Plain aquifers (where combined Ra (226Ra plus 228Ra) concentrations commonly exceed 0.185 Bq L-1) were determined. Softeners, when maintained, reduced combined Ra about 10-fold (septic-tank effluents receiving brine waste were less than in the untreated ground waters. The maximum combined Ra concentration in aquifer sands (40.7 Bq kg-1 dry weight) was less than that in sludge from the septic tanks (range, 84-363 Bq kg-1), indicating Ra accumulation in sludge from effluent. The combined Ra concentration in sludge from the homeowners' septic systems falls within the range reported for sludge samples from publicly owned treatment works within the region.

CHARACTERIZATION AND SETTLING TESTS WITH TANK 51H SLURRY SAMPLES HTF-076-081

International Nuclear Information System (INIS)

HAY, MICHAEL

2006-01-01

Sludge Batch 4 (SB4) is the next sludge batch being prepared for feed to the Defense Waste Processing Facility (DWPF). SB4 includes sludge from Tanks 5F, 6F, and 11H and heels from Tanks 7F and 51H. In preparation of SB4, sludge was transferred from Tank 11H to Tank 51H. The sludge currently in Tank 51H has been found to settle at slower rates than previous sludge batches. The slow sludge settling in Tank 51H impacts the ability to wash SB4 to the desired final weight percent insoluble solids and sodium endpoint. This could impact the ability to have SB4 ready on time to support DWPF and result in increased recycle back to the Tank Farm, reduced waste loading at DWPF, and lengthened cycle time in the DWPF Chemical Processing Cell (CPC) Sludge Receipt and Adjustment Tank (SRAT). The Savannah River National Laboratory (SRNL) was requested to characterize and investigate the slower settling rate with six slurry dip samples of Tank 51H sludge. The filtered supernate and the total dried solids of the sludge were analyzed and summaries of the results published in the references listed below. The sludge composition was found to be consistent with H-Area high aluminum sludge. Difficulties were encountered with dissolving all of the material in the dried sludge solids. An analysis of the undissolved material from the digestions found the main constituent was Boehmite (AlO(OH)). This report provides all of the compositional data and an analysis of the data with recommended values to use for the composition of the Tank 51H composite sample. Tables 3-2 through 3-4 provide the composition of the Tank 51H composite sample. Settling tests conducted with the Tank 51H sludge showed a much slower settling rate than with the sludge in Sludge Batch 3 (SB3). A mixture of Tank 51H and sludge from SB3 was prepared to mimic the projected final composition of Sludge Batch 4 (SB4). The mixture showed minimal improvement in the settling rate versus Tank 51H sludge alone. An attempt to

SBR treatment of tank truck cleaning wastewater: sludge characteristics, chemical and ecotoxicological effluent quality.

Science.gov (United States)

Caluwé, Michel; Dobbeleers, Thomas; Daens, Dominique; Geuens, Luc; Blust, Ronny; Dries, Jan

2017-08-02

A lab-scale activated sludge sequencing batch reactor (SBR) was used to treat tank truck cleaning (TTC) wastewater with different operational strategies (identified as different stages). The first stage was an adaptation period for the seed sludge that originated from a continuous fed industrial plant treating TTC wastewater. The first stage was followed by a dynamic reactor operation based on the oxygen uptake rate (OUR). Thirdly, dynamic SBR control based on OUR treated a daily changing influent. Lastly, the reactor was operated with a gradually shortened fixed cycle. During operation, sludge settling evolved from nearly no settling to good settling sludge in 16 days. The sludge volume index improved from 200 to 70 mL gMLSS -1 in 16 days and remained stable during the whole reactor operation. The average soluble chemical oxygen demand (sCOD) removal varied from 87.0% to 91.3% in the different stages while significant differences in the food to mass ratio were observed, varying from 0.11 (stage I) to 0.37 kgCOD.(kgMLVSS day) -1 (stage III). Effluent toxicity measurements were performed with Aliivibrio fischeri, Daphnia magna and Pseudokirchneriella subcapitata. Low sensitivity of Aliivibrio was observed. A few samples were acutely toxic for Daphnia; 50% of the tested effluent samples showed an inhibition of 100% for Pseudokirchneriella.

Oxidative dissolution of chromium from Hanford tank sludges under alkaline conditions

International Nuclear Information System (INIS)

Rapko, B.M.; Delegard, C.H.; Wagner, M.J.

1997-08-01

Alkaline oxidative leaching has been performed on caustic leached sludges from the three following Hanford waste tanks: BY-110, S-107, and SX-108. These samples were chosen because they represent types of waste where significant amounts of Cr are located and show relatively poor dissolution of Cr during standard caustic leaching. The experiments involved tests with three chemical oxidants, permanganate, ozone and oxygen, and a blank, argon. The effects of varying the hydroxide concentration of the leachate (from 0.1 M to 3 M) and of time and temperature (from room temperature to 80 degrees C) were also examined

Suspending Zeolite Particles In Tanks

International Nuclear Information System (INIS)

Poirier, M.R.

1999-01-01

The Savannah River Site (SRS) is in the process of removing waste (sludge and salt cake) from million gallon waste tanks. The current practice for removing waste from the tanks is adding water, agitating the tanks with long shaft vertical centrifugal pumps, and pumping the sludge/salt solution from the tank to downstream treatment processes. This practice has left sludge heels (tilde 30,000 gallons) in the bottom of the tanks. SRS is evaluating shrouded axial impeller mixers for removing the sludge heels in the waste tanks. The authors conducted a test program to determine mixer requirements for suspending sludge heels using the shrouded axial impeller mixers. The tests were performed with zeolite in scaled tanks which have diameters of 1.5, 6.0, and 18.75 feet. The mixer speeds required to suspend zeolite particles were measured at each scale. The data were analyzed with various scaling methods to compare their ability to describe the suspension of insoluble solids with the mixers and to apply the data to a full-scale waste tank. The impact of changes in particle properties and operating parameters was also evaluated. The conclusions of the work are: Scaling of the suspension of fast settling zeolite particles was best described by the constant power per unit volume method. Increasing the zeolite particle concentration increased the required mixer power needed to suspend the particles. Decreasing the zeolite particle size from 0.7 mm 0.3 mm decreased the required mixer power needed to suspend the particles. Increasing the number of mixers in the tank decreased the required mixer power needed to suspend the particles. A velocity of 1.6 ft/sec two inches above the tank bottom is needed to suspend zeolite particles

Effects of oxidation reduction potential in the bypass micro-aerobic sludge zone on sludge reduction for a modified oxic-settling-anaerobic process.

Science.gov (United States)

Li, Kexun; Wang, Yi; Zhang, Zhongpin; Liu, Dongfang

2014-01-01

Batch experiments were conducted to determine the effect of oxidation reduction potential (ORP) on sludge reduction in a bypass micro-aerobic sludge reduction system. The system was composed of a modified oxic-settling-anaerobic process with a sludge holding tank in the sludge recycle loop. The ORPs in the micro-aerobic tanks were set at approximately +350, -90, -150, -200 and -250 mV, by varying the length of aeration time for the tanks. The results show that lower ORP result in greater sludge volume reduction, and the sludge production was reduced by 60% at the lowest ORP. In addition, low ORP caused extracellular polymer substances dissociation and slightly reduced sludge activity. Comparing the sludge backflow characteristics of the micro-aerobic tank's ORP controlled at -250 mV with that of +350 mV, the average soluble chemical oxygen (SCOD), TN and TP increased by 7, 0.4 and 2 times, median particle diameter decreased by 8.5 μm and the specific oxygen uptake rate (SOUR) decreased by 0.0043 milligram O2 per gram suspended solids per minute. For the effluent, SCOD and TN and TP fluctuated around 30, 8.7 and 0.66 mg/L, respectively. Therefore, the effective assignment of ORP in the micro-aerobic tank can remarkably reduce sludge volume and does not affect final effluent quality.

Design characteristics of the Sludge Mobilization System

International Nuclear Information System (INIS)

McMahon, C.L.

1990-01-01

Radioactive waste stored in underground tanks at the West Valley Demonstration Project is being processed into low-level waste and solidified in cement. High-level waste also stored underground will be vitrified and solidified into canistered glass logs. To move the waste from where it resides at the Waste Tank Farm to the Vitrification Facility requires equipment to prepare the storage tanks for low-level and high-level waste processing, equipment to mobilize and mix the radioactive sludge into a homogeneous slurry, and equipment to transfer the slurry for vitrification. The design of the Sludge Mobilization System has incorporated the necessary components to effect the preparation and transfer of waste in five operational phases. The first phase of the Sludge Mobilization System, which began in 1987, prepared the waste tanks to process radioactive liquid for delivery to the Cement Solidification System and to support the mobilization equipment. The second phase, beginning in 1991, will wash the sludge that remains after the liquid supernatant is decanted to prepare it for mobilization operations. The third phase will combine the contents of various waste tanks into one tank. The fourth phase will resuspend and mix the contents of the high-level waste tank. The fifth and final phase of the Sludge Mobilization System will entail transferring the waste mixture to the Vitrification Facility for processing into glass logs. Provisions for recycling the waste streams or slurries within the tank farm or for returning process streams to the Waste Tank Farm from the Vitrification Facility are also included in the final phase. This document addresses the Sludge Mobilization System equipment design characteristics in terms of its use in each of the five operational phases listed above

Enhanced sludge washing evaluation plan

Energy Technology Data Exchange (ETDEWEB)

Jensen, R.D.

1994-09-01

The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices.

Enhanced sludge washing evaluation plan

International Nuclear Information System (INIS)

Jensen, R.D.

1994-09-01

The Tank Waste Remediation System (TWRS) Program mission is to store, treat, and immobilize highly radioactive Hanford Site waste (current and future tank waste and the strontium/cesium capsules) in an environmentally sound, safe, and cost-effective manner. The scope of the TWRS Waste Pretreatment Program is to treat tank waste and separate that waste into HLW and LLW fractions and provide additional treatment as required to feed LLW and HLW immobilization facilities. Enhanced sludge washing was chosen as the baseline process for separating Hanford tank waste sludge. Section 1.0 briefly discusses the purpose of the evaluation plan and provides the background that led to the choice of enhanced sludge washing as the baseline process. Section 2.0 provides a brief summary of the evaluation plan details. Section 3.0 discusses, in some detail, the technical work planned to support the evaluation of enhanced sludge washing. Section 4.0 briefly discusses the potential important of policy issues to the evaluation. Section 5.0 discusses the methodology to be used in the evaluation process. Section 6.0 summarizes the milestones that have been defined to complete the enhanced sludge washing evaluation and provides a summary schedule to evaluate the performance of enhanced sludge washing. References are identified in Section 7.0, and additional schedule and milestone information is provided in the appendices

Industrial mixing techniques for Hanford double-shell tanks

International Nuclear Information System (INIS)

Daymo, E.A.

1997-09-01

Jet mixer pumps are currently the baseline technology for sludge mobilization and mixing in one-million gallon double-shell tanks at the Hanford and Savannah River Sites. Improvements to the baseline jet mixer pump technology are sought because jet mixer pumps have moving parts that may fail or require maintenance. Moreover, jet mixers are relatively expensive, they heat the waste, and, in some cases, may not mobilize enough of the sludge. This report documents a thorough literature search for commercially available applicable mixing technologies that could be used for double-shell tank sludge mobilization and mixing. Textbooks, research articles, conference proceedings, mixing experts, and the Thomas Register were consulted to identify applicable technologies. While there are many commercial methods that could be used to mobilize sludge or mix the contents of a one-million gallon tank, few will work given the geometrical constraints (e.g., the mixer must fit through a 1.07-m-diameter riser) or the tank waste properties (e.g., the sludge has such a high yield stress that it generally does not flow under its own weight). Pulsed fluid jets and submersible Flygt mixers have already been identified at Hanford and Savannah River Sites for double-shell tank mixing applications. While these mixing technologies may not be applicable for double-shell tanks that have a thick sludge layer at the bottom (since too many of these mixers would need to be installed to mobilize most of the sludge), they may have applications in tanks that do not have a settled solids layer. Retrieval projects at Hanford and other U.S. Department of Energy sites are currently evaluating the effectiveness of these mixing techniques for tank waste applications. The literature search did not reveal any previously unknown technologies that should be considered for sludge mobilization and mixing in one-million gallon double-shell tanks

Caustic Leaching of SRS Tank 12H Sludge With and Without Chelating Agents

International Nuclear Information System (INIS)

Spencer, B.B.

2003-01-01

The primary objective of this study was to measure the effect of adding triethanolamine (TEA) to caustic leaching solutions to improve the solubility of aluminum in actual tank-waste sludge. High-level radioactive waste sludge that had a high aluminum assay was used for the tests. This waste, which originated with the processing of aluminum-clad/aluminum-alloy fuels, generates high levels of heat because of the high 90 Sr concentration and contains hard-to-dissolve boehmite phases. In concept, a chelating agent, such as TEA, can both improve the dissolution rate and increase the concentration in the liquid phase. For this reason, TEA could also increase the solubility of other sludge components that are potentially problematic to downstream processing. Tests were conducted to determine if this were the case. Because of its relatively high vapor pressure, process design should include methods to minimize losses of the TEA. Sludge was retrieved from tank 12H at the Savannah River Site by on-site personnel, and then shipped to Oak Ridge National Laboratory for the study. The sludge contained a small quantity of rocky debris. One slate-like flat piece, which had approximate dimensions of 1 1/4 x 1/2 x 1/8 in., was recovered. Additional gravel-like fragments with approximate diameters ranging from 1/8 to 1/4 in. were also recovered by sieving the sludge slurry through a 1.4-mm square-pitch stainless steel mesh. These particles ranged from a yellow quartz-like material to grey-colored gravel. Of the 32.50 g of sludge received, the mass of the debris was only 0.89 g, and the finely divided sludge comprised ∼97% of the mass. The sludge was successfully subdivided into uniform aliquots during hot-cell operations. Analytical measurements confirmed the uniformity of the samples. The smaller sludge samples were then used as needed for leaching experiments conducted in a glove box. Six tests were performed with leachate concentrations ranging from 0.1 to 3.0 m NaOH, 0 to 3

Solid-phase characterization in flammable-gas-tank sludges by electron microscopy

International Nuclear Information System (INIS)

Liu, J.; Pederson, L.R.; Qang, L.Q.

1995-09-01

The crystallinity, morphology, chemical composition, and crystalline phases of several Tank 241-SY-101 (hereinafter referred to as SY-101) and Tank 241-SY-103 (hereinafter referred to as SY-103) solid samples were studied by transmission electron microscopy (TEM), electron energy dispersive spectroscopy (EDS), and electron diffraction. The main focus is on the identification of aluminum hydroxide thought to be present in these tank samples. Aluminum hydroxide was found in SY-103, but not in SY-101. This difference can be explained by the different OH/Al ratios found in the two tank samples: a high OH/Al ratio in SY-101 favors the formation of sodium aluminate, but a low OH/Al ratio in SY-103 favors aluminum hydroxide. These results were confirmed by a magnetic resonance study on SY-101 and SY-103 simulant. The transition from aluminum hydroxide to sodium aluminate occurs at an OH/Al molar ratio of 3.6. It is believed that the study of Al(OH) 3 was not affected by sample preparation because all Al(OH) 3 is in the solid form according to the NMR experiments. There is no Al(OH) 3 in the liquid. It is, therefore, most likely that the observation of Al(OH) 3 is representative of the real sludge sample, and is not affected by drying. Similar conclusions also apply to other insoluble phases such as iron and chromium

TANK 21 AND TANK 24 BLEND AND FEED STUDY: BLENDING TIMES, SETTLING TIMES, AND TRANSFERS

Energy Technology Data Exchange (ETDEWEB)

Lee, S.; Leishear, R.; Poirier, M.

2012-05-31

The Salt Disposition Integration (SDI) portfolio of projects provides the infrastructure within existing Liquid Waste facilities to support the startup and long term operation of the Salt Waste Processing Facility (SWPF). Within SDI, the Blend and Feed Project will equip existing waste tanks in the Tank Farms to serve as Blend Tanks where salt solutions of up to 1.2 million gallons will be blended in 1.3 million gallon tanks and qualified for use as feedstock for SWPF. In particular, Tanks 21 and 24 are planned to be used for blending and transferring to the SDI feed tank. These tanks were evaluated here to determine blending times, to determine a range of settling times for disturbed sludge, and to determine that the SWPF Waste Acceptance Criteria that less than 1200 mg/liter of solids will be entrained in salt solutions during transfers from the Tank 21 and Tank 24 will be met. Overall conclusions for Tank 21 and Tank 24 operations include: (1) Experimental correction factors were applied to CFD (computational fluid dynamics) models to establish blending times between approximately two and five hours. As shown in Phase 2 research, blending times may be as much as ten times greater, or more, if lighter fluids are added to heavier fluids (i.e., water added to salt solution). As the densities of two salt solutions converge this effect may be minimized, but additional confirmatory research was not performed. (2) At the current sludge levels and the presently planned operating heights of the transfer pumps, solids entrainment will be less than 1200 mg/liter, assuming a conservative, slow settling sludge simulant. (3) Based on theoretical calculations, particles in the density range of 2.5 to 5.0 g/mL must be greater than 2-4 {micro}m in diameter to ensure they settle adequately in 30-60 days to meet the SWPF feed criterion (<1200 mg/l). (4) Experimental tests with sludge batch 6 simulant and field turbidity data from a recent Tank 21 mixing evolution suggest the solid

Deep Sludge Gas Release Event Analytical Evaluation

International Nuclear Information System (INIS)

Sams, Terry L.

2013-01-01

Long Abstract. Full Text. The purpose of the Deep Sludge Gas Release Event Analytical Evaluation (DSGRE-AE) is to evaluate the postulated hypothesis that a hydrogen GRE may occur in Hanford tanks containing waste sludges at levels greater than previously experienced. There is a need to understand gas retention and release hazards in sludge beds which are 200 -300 inches deep. These sludge beds are deeper than historical Hanford sludge waste beds, and are created when waste is retrieved from older single-shell tanks (SST) and transferred to newer double-shell tanks (DST).Retrieval of waste from SSTs reduces the risk to the environment from leakage or potential leakage of waste into the ground from these tanks. However, the possibility of an energetic event (flammable gas accident) in the retrieval receiver DST is worse than slow leakage. Lines of inquiry, therefore, are (1) can sludge waste be stored safely in deep beds; (2) can gas release events (GRE) be prevented by periodically degassing the sludge (e.g., mixer pump); or (3) does the retrieval strategy need to be altered to limit sludge bed height by retrieving into additional DSTs? The scope of this effort is to provide expert advice on whether or not to move forward with the generation of deep beds of sludge through retrieval of C-Farm tanks. Evaluation of possible mitigation methods (e.g., using mixer pumps to release gas, retrieving into an additional DST) are being evaluated by a second team and are not discussed in this report. While available data and engineering judgment indicate that increased gas retention (retained gas fraction) in DST sludge at depths resulting from the completion of SST 241-C Tank Farm retrievals is not expected and, even if gas releases were to occur, they would be small and local, a positive USQ was declared (Occurrence Report EM-RP--WRPS-TANKFARM-2012-0014, 'Potential Exists for a Large Spontaneous Gas Release Event in Deep Settled Waste Sludge'). The purpose of this technical

Utilization of the MPI Process for in-tank solidification of heel material in large-diameter cylindrical tanks

Energy Technology Data Exchange (ETDEWEB)

Kauschinger, J.L.; Lewis, B.E.

2000-01-01

A major problem faced by the US Department of Energy is remediation of sludge and supernatant waste in underground storage tanks. Exhumation of the waste is currently the preferred remediation method. However, exhumation cannot completely remove all of the contaminated materials from the tanks. For large-diameter tanks, amounts of highly contaminated ``heel'' material approaching 20,000 gal can remain. Often sludge containing zeolite particles leaves ``sand bars'' of locally contaminated material across the floor of the tank. The best management practices for in-tank treatment (stabilization and immobilization) of wastes require an integrated approach to develop appropriate treatment agents that can be safely delivered and mixed uniformly with sludge. Ground Environmental Services has developed and demonstrated a remotely controlled, high-velocity jet delivery system termed, Multi-Point-Injection (MPI). This robust jet delivery system has been field-deployed to create homogeneous monoliths containing shallow buried miscellaneous waste in trenches [fiscal year (FY) 1995] and surrogate sludge in cylindrical (FY 1998) and long, horizontal tanks (FY 1999). During the FY 1998 demonstration, the MPI process successfully formed a 32-ton uniform monolith of grout and waste surrogates in about 8 min. Analytical data indicated that 10 tons of zeolite-type physical surrogate were uniformly mixed within a 40-in.-thick monolith without lifting the MPI jetting tools off the tank floor. Over 1,000 lb of cohesive surrogates, with consistencies similar to Gunite and Associated Tank (GAAT) TH-4 and Hanford tank sludges, were easily intermixed into the monolith without exceeding a core temperature of 100 F during curing.

Hydrogen production during processing of radioactive sludge containing noble metals

International Nuclear Information System (INIS)

Ha, B.C.; Ferrara, D.M.; Bibler, N.E.

1992-01-01

Hydrogen was produced when radioactive sludge from Savannah River Site radioactive waste containing noble metals was reacted with formic acid. This will occur in a process tank in the Defense Waste Facility at SRS when waste is vitrified. Radioactive sludges from four tanks were tested in a lab-scale apparatus. Maximum hydrogen generation rates varied from 5 x10 -7 g H 2 /hr/g of sludge from the least reactive sludge (from Waste Tank 51) to 2 x10 -4 g H 2 /hr/g of sludge from the most reactive sludge (from Waste Tank 11). The time required for the hydrogen generation to reach a maximum varied from 4.1 to 25 hours. In addition to hydrogen, carbon dioxide and nitrous oxide were produced and the pH of the reaction slurry increased. In all cases, the carbon dioxide and nitrous oxide were generated before the hydrogen. The results are in agreement with large-scale studies using simulated sludges

History of waste tank 13, 1956 through 1974

International Nuclear Information System (INIS)

Davis, T.L.; Tharin, D.W.; Lohr, D.R.

1978-06-01

Tank 13 was placed in service as a receiver of LW from the Building 221-H Purex process in December 1956. Five years later, the supernate was decanted to evaporator feed tank 21. It has since served as a transfer tank for HW supernate being sent to tank 21 and has received sludge removed from other tanks four times. The tank annulus has been inspected with an optical periscope and a lead-shielded camera. No indication of tank leakage had been seen through December 1974. However, subsequent to this report (on April 14, 1977), an arrested leak was discovered, making tank 13 the last of the four type II tanks to leak. Analytical samples of supernate and sludge have been taken. Tank 13 has had no cooling coil failures. Primary tank wall thicknesses, sludge level determinations, and temperature profiles have been obtained. Tank 13 has been included in various tests. Equipment modifications and various equipment repairs were made. 11 figures, 2 tables

[Analysis of carbon balance and study on mechanism in anoxic-oxic-settling-anaerobic sludge reduction process].

Science.gov (United States)

Zhai, Xiao-Min; Gao, Xu; Zhang, Man-Man; Jia, Li; Guo, Jin-Song

2012-07-01

In order to deeply explore the mechanism of sludge reduction in OSA system, carbon balance was performed in an anoxic-oxic-settling-anaerobic (A + OSA) system and a reference AO system to investigate effects of inserting a sludge holding tank in sludge cycle line on the sludge reduction process. Meanwhile, carbon mass change in each reaction unit was identified in terms of solid, liquid and gas phases. The causes of excess sludge reduction in A + OSA system were deduced. The carbon balance results show that when the hydraulic retention time in the sludge holding tank is 7.14 h, carbon percent in solid phase of the sludge reduction system is nearly 50% higher than that of the reference system, supporting the consequence that sludge reduction rate of 49.98% had been achieved. The insertion of a sludge holding tank in the sludge return circuit can be effective in sludge reduction. Carbon changes in each unit reveal that the amount of carbon consumed for biosynthesis in the anoxic and oxic tanks (main reaction zone) of the sludge reduction system is higher than in that of the reference system. Sludge decay is observed in the sludge holding tank. Furthermore, CH4 released from the sludge holding tank is significantly higher than that from the main reaction zone. The DGGE profiles show that there are hydrolytic-fermentative bacteria in the sludge holding tank related to sludge decay. The excess sludge reduction in the A + OSA system could be a result of the combination of sludge decay in the sludge holding tank and sludge compensatory growth in the main reaction cell.

Physical Properties of Hanford Transuranic Waste Sludge

International Nuclear Information System (INIS)

Poloski, A. P.

2004-01-01

This project has two primary objectives. The first is to understand the physical properties and behavior of the Hanford transuranic (TRU) tank sludges under conditions that might exist during retrieval, treatment, packaging, and transportation for disposal at WIPP. The second primary objective is to develop a fundamental understanding of these sludge suspensions by correlating the macroscopic properties with particle interactions occurring at the colloidal scale in the various liquid media. The results of this research effort will enhance the existing understanding of agglomeration phenomena and the properties of complex colloidal suspensions. In addition, the knowledge gained and capabilities developed during this effort will aid in the development and optimization of techniques to process the wastes at various DOE sites. These objectives will be accomplished by: (1) characterizing the TRU sludges contained in the Hanford tanks that are intended for shipment to WIPP; (2) determining the physical behavior of the Hanford TRU tank sludges under conditions that might exist during treatment and packaging; (3) and modeling the retrieval, treatment, and packaging operations that will be performed at Hanford to dispose of TRU tank sludges

Treatment of radioactive wastes from DOE underground storage tanks

International Nuclear Information System (INIS)

Collins, J.L.; Egan, B.Z.; Spencer, B.B.; Chase, C.W.; Anderson, K.K.; Bell, J.T.

1994-01-01

Bench-scale batch tests have been conducted with sludge and supernate tank waste from the Melton Valley Storage Tank (MVST) Facility at Oak Ridge National Laboratory (ORNL) to evaluate separation technology process for use in a comprehensive sludge processing flow sheet as a means of concentrating the radionuclides and reducing the volumes of storage tank waste at national sites for final disposal. This paper discusses the separation of the sludge solids and supernate, the basic washing of the sludge solids, the acidic dissolution of the sludge solids, and the removal of the radionuclides from the supernate

Tank Vapor Sampling and Analysis Data Package for Tank 241-Z-361 Sampled 09/22/1999 and 09/27/1999, During Sludge Core Removal

International Nuclear Information System (INIS)

VISWANATH, R.S.

1999-01-01

This data package presents sampling data and analytical results from the September 22 and 27, 1999, headspace vapor sampling of Hanford Site Tank 241-2-361 during sludge core removal. The Lockheed Martin Hanford Corporation (LMHC) sampling team collected the samples and Waste Management Laboratory (WML) analyzed the samples in accordance with the requirements specified in the 241-2361 Sludge Characterization Sampling and Analysis Plan, (SAP), HNF-4371/Rev. 1, (Babcock and Wilcox Hanford Corporation, 1999). Six SUMMA(trademark) canister samples were collected on each day (1 ambient field blank and 5 tank vapor samples collected when each core segment was removed). The samples were radiologically released on September 28 and October 4, 1999, and received at the laboratory on September 29 and October 6, 1999. Target analytes were not detected at concentrations greater than their notification limits as specified in the SAP. Analytical results for the target analytes and tentatively identified compounds (TICs) are presented in Section 2.2.2 starting on page 2B-7. Three compounds identified for analysis in the SAP were analyzed as TICs. The discussion of this modification is presented in Section 2.2.1.2

Sumi-sludge system; Sumisurajji system

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-04-20

The subject facilities, delivered to Kakegawa City, Shizuoka Prefecture, in December, 1999, are the first machine by the heavy load denitrification processing system adaptive to purifying tank sludge 'Sumi-sludge system'. It enhanced the capacity of 84 kl/day by about 30% to 109 kl/day through the remodeling of the existing facilities. Its major specifications are capacity: 109 kl/day (human wastes 18 kl/day, purifying tank sludge 91 kl/day) and final effluent quality: pH 5.8-8.6, BOD 10 mg/l or less, COD 20 mg/l or less, SS 10 mg/l or less, T-N 10 mg/l or less, T-P 1 mg/l or less, chromaticity 30 degrees or less, coliform group quantity 3,000 pieces/ml or less. It has the following features. (1) Bio-treatment load is reduced by dehydrating human wastes and purifying tank sludge in the prestage of the bio-treatment. (2) Bio-treatment and flocculation separating treatment are integrated. (3) A high-speed flocculation sedimentation tank 'Sumi-thickner' is employed in the solid-liquid separator, enabling stable solid-liquid separation. (translated by NEDO)

Surveillance and maintenance plan for the inactive liquid low-level waste tanks at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

1994-11-01

ORNL has a total of 54 inactive liquid low-level waste (ILLLW) tanks. In the past, these tanks were used to contain radioactive liquid wastes from various research programs, decontamination operations, and reactor operations. The tanks have since been removed from service for various reasons; the majority were retired because of their age, some due to integrity compromises, and others because they did not meet the current standards set by the Federal Facilities Agreement (FFA). Many of the tanks contain residual radioactive liquids and/or sludges. Plans are to remediate all tanks; however, until remediation of each tank, this Surveillance and Maintenance (S ampersand M) Plan will be used to monitor the safety and inventory containment of these tanks

Effect of sludge solids to mono-sodium titanate (MST) ratio on MST-treated sludge

International Nuclear Information System (INIS)

Saito, H.H.

1999-01-01

The Salt Disposition Systems Engineering Team has selected two cesium removal technologies for further development to replace the In-Tank Precipitation process: small tank tetraphenylborate (TPB) precipitation and crystalline silicotitanate (CST) ion exchange. In the CST ion exchange process, incoming salt solution from storage tanks containing entrained sludge solids is pretreated with monosodium titanate (MST) to adsorb strontium and plutonium. The resulting slurry is filtered using a cross-flow filter, with the permeate sent forward to CST ion exchange columns for cesium removal prior to conversion into Class A grout at the Saltstone Facility. The MST and sludge solids are to be sent for vitrification at the Defense Waste Processing Facility (DWPF). The High Level Waste Division (HLWD) requested that the Waste Processing Technology Section (WPTS) study varying the insoluble sludge solids to MST ratio to determine the relative impact of sludge and MST on filter performance. The purpose of this study was not for an exhaustive comprehensive search for an optimized insoluble sludge solids to monosodium titanate (MST) ratio, but as a scoping study to identify any effects of having an excess of either material. This document reports the results obtained

Numerical Modelling and Measurement in a Test Secondary Settling Tank

DEFF Research Database (Denmark)

Dahl, C.; Larsen, Torben; Petersen, O.

1994-01-01

sludge. Phenomena as free and hindered settling and the Bingham plastic characteristic of activated sludge suspensions are included in the numerical model. Further characterisation and test tank experiments are described. The characterisation experiments were designed to measure calibration parameters...... for model description of settling and density differences. In the test tank experiments, flow velocities and suspended sludge concentrations were measured with different tank inlet geomotry and hydraulic and sludge loads. The test tank experiments provided results for the calibration of the numerical model......A numerical model and measurements of flow and settling in activated sludge suspension is presented. The numerical model is an attempt to describe the complex and interrelated hydraulic and sedimentation phenomena by describing the turbulent flow field and the transport/dispersion of suspended...

Effect of sewage sludge content on gas quality and solid residues produced by cogasification in an updraft gasifier

Energy Technology Data Exchange (ETDEWEB)

Seggiani, Maurizia, E-mail: m.seggiani@diccism.unipi.it [Department of Chemical Engineering, Industrial Chemistry and Material Science, University of Pisa, Largo Lucio Lazzarino 1, 56126 Pisa (Italy); Puccini, Monica, E-mail: m.puccini@diccism.unipi.it [Department of Chemical Engineering, Industrial Chemistry and Material Science, University of Pisa, Largo Lucio Lazzarino 1, 56126 Pisa (Italy); Raggio, Giovanni, E-mail: g.raggio@tiscali.it [Italprogetti Engineering SPA, Lungarno Pacinotti, 59/A, 56020 San Romano (Pisa) (Italy); Vitolo, Sandra, E-mail: s.vitolo@diccism.unipi.it [Department of Chemical Engineering, Industrial Chemistry and Material Science, University of Pisa, Largo Lucio Lazzarino 1, 56126 Pisa (Italy)

2012-10-15

Highlights: Black-Right-Pointing-Pointer Cogasification of sewage sludge with wood pellets in updraft gasifier was analysed. Black-Right-Pointing-Pointer The effects of sewage sludge content on the gasification process were examined. Black-Right-Pointing-Pointer Sewage sludge addition up to 30 wt.% reduces moderately the process performance. Black-Right-Pointing-Pointer At high sewage sludge content slagging and clinker formation occurred. Black-Right-Pointing-Pointer Solid residues produced resulted acceptable at landfills for non-hazardous waste. - Abstract: In the present work, the gasification with air of dehydrated sewage sludge (SS) with 20 wt.% moisture mixed with conventional woody biomass was investigated using a pilot fixed-bed updraft gasifier. Attention was focused on the effect of the SS content on the gasification performance and on the environmental impact of the process. The results showed that it is possible to co-gasify SS with wood pellets (WPs) in updraft fixed-bed gasification installations. However, at high content of sewage sludge the gasification process can become instable because of the very high ash content and low ash fusion temperatures of SS. At an equivalent ratio of 0.25, compared with wood pellets gasification, the addition of sewage sludge led to a reduction of gas yield in favor of an increase of condensate production with consequent cold gas efficiency decrease. Low concentrations of dioxins/furans and PAHs were measured in the gas produced by SS gasification, well below the limiting values for the exhaust gaseous emissions. NH{sub 3}, HCl and HF contents were very low because most of these compounds were retained in the wet scrubber systems. On the other hand, high H{sub 2}S levels were measured due to high sulfur content of SS. Heavy metals supplied with the feedstocks were mostly retained in gasification solid residues. The leachability tests performed according to European regulations showed that metals leachability was

Optimization and control of the activated sludge process by adaptation of aeration tank volume

Energy Technology Data Exchange (ETDEWEB)

Staud, R

1982-04-01

Purpose of full scale studies conducted at a municipal wastewater treatment plant at Schwetzingen, Germany, was to optimize the activated sludge treatment process. Influent loading fluctuations were answered by operating a distinct number of the four parallel treatment plant units (aeration tank/clarifier) present. During the intermediate period of time the aerators were also switched off, and the activated sludge was kept anaerobically. The purpose of this particular technique is to equalize the nutrient supply of the microorganisms to gain an improved metabolic potential, as well as to decrease the energy demand for aeration. A mathematical algorithm for process control was developed to accomplish this technique. Initial parameters are inflow rate, MLSS and plateau-BOD to evaluate the substrate concentration. The results of the full scale studies prove the practicability of this concept. Equalization of the F:M ratio fluctuations leads to an increase of the average substrate loading but not to any decrease in the overall process efficiency. Anaerobic sludge storage did not cause any problem. Odor problems could be handled by limitation of the storage period to 24 hours. As far as energy consumption for aeration is concerned a decrease by 47% percent could be achieved.

Improving material and energy recovery from the sewage sludge and biomass residues.

Science.gov (United States)

Kliopova, Irina; Makarskienė, Kristina

2015-02-01

Sewage sludge management is a big problem all over the world because of its large quantities and harmful impact on the environment. Energy conversion through fermentation, compost production from treated sludge for agriculture, especially for growing energetic plants, and treated sludge use for soil remediation are widely used alternatives of sewage sludge management. Recently, in many EU countries the popularity of these methods has decreased due to the sewage sludge content (heavy metals, organic pollutions and other hazards materials). This paper presents research results where the possibility of solid recovered fuel (SRF) production from the separate fraction (10-40 mm) of pre-composted materials--sewage sludge from municipal waste water treatment plant and biomass residues has been evaluated. The remaining fractions of pre-composted materials can be successfully used for compost or fertiliser production, as the concentration of heavy metals in the analysed composition is reduced in comparison with sewage sludge. During the experiment presented in this paper the volume of analysed biodegradable waste was reduced by 96%: about 20% of input biodegradable waste was recovered to SRF in the form of pellets with 14.25 MJ kg(-1) of the net calorific value, about 23% were composted, the rest--evaporated and discharged in a wastewater. The methods of material-energy balances and comparison analysis of experiment data have been chosen for the environmental impact assessment of this biodegradable waste management alternative. Results of the efficiency of energy recovery from sewage sludge by SRF production and burning, comparison analysis with widely used bio-fuel-sawdust and conclusions made are presented. Copyright © 2014 Elsevier Ltd. All rights reserved.

Efeito residual do lodo de esgoto na produtividade do milho safrinha Residual effect of sewage sludge on off-season corn yield

Directory of Open Access Journals (Sweden)

Graziela Moraes de Cesare Barbosa

2007-06-01

Full Text Available Das opções de disposição final do lodo de esgoto, a reciclagem agrícola tem sido uma das mais utilizadas em diversos países desenvolvidos, sendo considerada a forma mais adequada em termos técnicos, econômicos e ambientais. Este trabalho teve por objetivo avaliar o efeito residual do lodo de esgoto na produtividade do milho safrinha, após dois anos de aplicação consecutiva desse resíduo em um Latossolo Vermelho eutroférrico. O experimento foi realizado em campo, em delineamento em blocos ao acaso com três repetições, e os tratamentos foram os seguintes: testemunha e adubações com lodo de esgoto nas doses de 6, 12, 24 e 36 t ha-1 (peso de matéria seca. Houve efeito residual do uso do lodo de esgoto caleado na produtividade de milho safrinha; a dose de 36 t ha-1 foi estatisticamente superior às doses de 6 e 12 t ha-1.Among the possibilities of final disposal of sewage sludge, agricultural recycling has become one of the most widely used in several developed countries, and is considered the most appropriate in technical, economical and environmental terms. This study aimed at evaluating the sewage sludge residual effect on off-season corn yield on an Eutroferric Red Latossol (Oxisol. The field experiment was in a randomized block design with three replications, with treatments consisting of increasing doses of sewage sludge (0, 6, 12, 24 and 36 t ha-1, on a dry weight basis, applied in the two previous cropping seasons.. The residual effect of the application of lime-stabilized sewage sludge increased the yield of off-season corn; the grain yield under a rate of 36 t ha-1 was statistically higher than those under 6 and 12 t ha-1.

Experience with Stabilization of SGHWR Sludge in a Commercial Plant in the United Kingdom

International Nuclear Information System (INIS)

Hagan, M.; Cornell, R.M.; Riley, B.; Ware, B.

2009-01-01

buffer store to hold the completed drums. After completion, drums are moved in a shielded overpack to the Treated Radwaste Store located on a different part of the Winfrith site. More than 300 m 3 of active sludge, held in four adjacent concrete tanks, has now been stabilised into 978 drums that have been placed into the dedicated store. The process of recovery and homogenization of the residual sludge in the bottom of each tank to the required specification will be described together with the means of recovery and disposal options for a quantity of unexpected materials found at the bottom of each unit. The means of dealing with the final quantities of sludge and water from the last two concrete tanks by recovering it into a tall steel filtration vessel located within one concrete tank will also be described. The final aspects of the paper will briefly describe the approach to be adopted for the final decontamination and demolition of both the EAST facility and WETP plant. The WETP plant is now in the latter stages of commercial operation leading to a second programme of stabilisation of a quantity of thorium metal for UKAEA ahead of its final decommissioning and demolition. (authors)

SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 6 QUALIFICATION

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J.; Pickenheim, B.; Bannochie, C.; Billings, A.; Bibler, N.; Click, D.

2010-10-01

Prior to initiating a new sludge batch in the Defense Waste Processing Facility (DWPF), Savannah River National Laboratory (SRNL) is required to simulate this processing, including Chemical Process Cell (CPC) simulation, waste glass fabrication, and chemical durability testing. This report documents this simulation for the next sludge batch, Sludge Batch 6 (SB6). SB6 consists of Tank 12 material that has been transferred to Tank 51 and subjected to Low Temperature Aluminum Dissolution (LTAD), Tank 4 sludge, and H-Canyon Pu solutions. Following LTAD and the Tank 4 addition, Liquid Waste Operations (LWO) provided SRNL a 3 L sample of Tank 51 sludge for SB6 qualification. Pu solution from H Canyon was also received. SB6 qualification included washing the sample per LWO plans/projections (including the addition of Pu from H Canyon), DWPF CPC simulations, waste glass fabrication (vitrification), and waste glass characterization and chemical durability evaluation. The following are significant observations from this demonstration. Sludge settling improved slightly as the sludge was washed. SRNL recommended (and the Tank Farm implemented) one less wash based on evaluations of Tank 40 heel projections and projections of the glass composition following transfer of Tank 51 to Tank 40. Thorium was detected in significant quantities (>0.1 wt % of total solids) in the sludge. In past sludge batches, thorium has been determined by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS), seen in small quantities, and reported with the radionuclides. As a result of the high thorium, SRNL-AD has added thorium to their suite of Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) elements. The acid stoichiometry for the DWPF Sludge Receipt and Adjustment Tank (SRAT) processing of 115%, or 1.3 mol acid per liter of SRAT receipt slurry, was adequate to accomplish some of the goals of SRAT processing: nitrite was destroyed to below 1,000 mg/kg and mercury was removed to

241-Z-361 Sludge Characterization Sampling and Analysis Plan

Energy Technology Data Exchange (ETDEWEB)

BANNING, D.L.

1999-08-05

This sampling and analysis plan (SAP) identifies the type, quantity, and quality of data needed to support characterization of the sludge that remains in Tank 241-2-361. The procedures described in this SAP are based on the results of the 241-2-361 Sludge Characterization Data Quality Objectives (DQO) (BWHC 1999) process for the tank. The primary objectives of this project are to evaluate the contents of Tank 241-2-361 in order to resolve safety and safeguards issues and to assess alternatives for sludge removal and disposal.

241-Z-361 Sludge Characterization Sampling and Analysis Plan

Energy Technology Data Exchange (ETDEWEB)

BANNING, D.L.

1999-07-29

This sampling and analysis plan (SAP) identifies the type, quantity, and quality of data needed to support characterization of the sludge that remains in Tank 241-2-361. The procedures described in this SAP are based on the results of the 241-2-361 Sludge Characterization Data Quality Objectives (DQO) (BWHC 1999) process for the tank. The primary objectives of this project are to evaluate the contents of Tank 241-2-361 in order to resolve safety and safeguards issues and to assess alternatives for sludge removal and disposal.

Modeling and analysis of ORNL horizontal storage tank mobilization and mixing

International Nuclear Information System (INIS)

Mahoney, L.A.; Terrones, G.; Eyler, L.L.

1994-06-01

The retrieval and treatment of radioactive sludges that are stored in tanks constitute a prevalent problem at several US Department of Energy sites. The tanks typically contain a settled sludge layer with non-Newtonian rheological characteristics covered by a layer of supernatant. The first step in retrieval is the mobilization and mixing of the supernatant and sludge in the storage tanks. Submerged jets have been proposed to achieve sludge mobilization in tanks, including the 189 m 3 (50,000 gallon) Melton Valley Storage tanks (MVST) at Oak Ridge National Laboratory (ORNL) and the planned 378 m 3 (100,000 gallon) tanks being designed as part of the MVST Capacity Increase Project (MVST-CIP). This report focuses on the modeling of mixing and mobilization in horizontal cylindrical tanks like those of the MVST design using submerged, recirculating liquid jets. The computer modeling of the mobilization and mixing processes uses the TEMPEST computational fluid dynamics program (Trend and Eyler 1992). The goals of the simulations are to determine under what conditions sludge mobilization using submerged liquid jets is feasible in tanks of this configuration, and to estimate mixing times required to approach homogeneity of the contents

Sewage sludge additive

Science.gov (United States)

Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

1980-01-01

The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

Residual sludge from dimensional stones: characterisation for their exploitation in civil and environmental applications

Science.gov (United States)

Antonella Dino, Giovanna; Clemente, Paolo; De Luca, Domenico Antonio; Lasagna, Manuela

2013-04-01

Residual sludge coming from dimensional stones working plants (diamond framesaw and ganguesaw with abrasive shots processes) represents a problem for Stone Industries. In fact the cost connected to their landfilling amounts to more than 3% of operating costs of dimensional stone working plants. Furthermore their strict feature as waste to dump (CER code 010413) contrasts the EU principles of "resource preservation" and "waste recovery". The main problems related to their management are: size distribution (fine materials, potentially asphyxial), presence of heavy metals (due to the working processes) and TPH content (due to oil machines losses). Residual sludge, considered according to Italian Legislative Decree n.152/06, can be used, as waste, for environmental restoration of derelict land or in cement plants. It is also possible to think about their systematic treatment in consortium plats for the production of Secondary Raw Materials (SRM) or "New Products" (NP, eg. artificial loam, waterproofing materials, ....). The research evidences that, on the basis of a correct sludge management, treatment and characterization, economic and environmental benefits are possible (NP or SRM in spite of waste to dump). To individuate different applications of residual sludge in civil and environmental contexts, a geotechnical (size distribution, permeability, Atterberg limits, cohesion and friction angle evaluation, Proctor soil test) characterization was foreseen. The geotechnical tests were conducted on sludge as such and on three different mixes: - Mix 1 - Bentonite clay (5-10%) added to sludge a.s (90-95%); - Mix 2 - Sludge a.s. (90-80-70%) added to coarse materials coming from crushed dimensional stones (10-20-30%); - Mix 3 - Sludge a.s. (50-70%) mixed with sand, compost, natural loam (50-30% mixture of sand, compost, natural loam). The results obtained from the four sets of tests were fundamental to evaluate: - the characteristics of the original materials; - the chance

Sampling and analyses of SRP high-level waste sludges

International Nuclear Information System (INIS)

Stone, J.A.; Kelley, J.A.; McMillan, T.S.

1976-08-01

Twelve 3-liter samples of high-heat waste sludges were collected from four Savannah River Plant waste tanks with a hydraulically operated sample collector of unique design. Ten of these samples were processed in Savannah River Laboratory shielded cell facilities, yielding 5.3 kg of washed, dried sludge products for waste solidification studies. After initial drying, each batch was washed by settling and decantation to remove the bulk of soluble salts and then was redried. Additional washes were by filtration, followed by final drying. Conclusions from analyses of samples taken during the processing steps were: (a) the raw sludges contained approximately 80 wt percent soluble salts, most of which were removed by the washes; (b) 90 Sr and 238 , 239 Pu remained in the sludges, but most of the 137 Cs was removed by washing; (c) small amounts of sodium, sulfate, and 137 Cs remained in the sludges after thorough washing; (d) no significant differences were found in sludge samples taken from different risers of one waste tank. Chemical and radiometric compositions of the sludge product from each tank were determined. The sludges had diverse compositions, but iron, manganese, aluminum, and uranium were principal elements in each sludge. 90 Sr was the predominant radionuclide in each sludge product

Separation, Characterization and Fouling Potential of Sludge Waters from Different Biological Wastewater Treatment Processes

KAUST Repository

Xue, Jinkai

2011-07-01

The major limitation, which hinders the wider application of membrane technology and increases the operating costs of membranes involved in wastewater treatment plants, is membrane fouling induced by organic matter. Extracellular polymeric products (EPS) and soluble microbial products (SMP) are the two most mentioned major foulants in publications, for which the debate on precise definitions seems to be endless. Therefore, a concept of sludge water, which conceptually covers both EPS and SMP, has been developed in this research. A standard procedure of sludge water separation, which is centrifugation at 4000g for 15 min followed by 1.2μm glass fiber filter filtration, was established based on separation experiments with membrane tank sludge from the KAUST MBR wastewater treatment plant. Afterwards, sludge waters from the KAUST MBR WWTP anoxic tank, aerobic tank and membrane tank as well as sludge waters from the Jeddah WWTP anoxic tank, aerobic tank and secondary effluent were produced through the previously developed standard procedure. The obtained sludge water samples were thereafter characterized with TOC/COD, LC-­‐OCD and F-­‐EEM, which showed that KAUST anoxic/ aerobic /membrane tank sludge waters had similar characteristics for all investigated parameters, yet the influent naturally had a higher DOC and biopolymer concentration. Moreover, lower TOC/COD, negligible biopolymers and low levels of humics were found in KAUST effluent. Compared with the KAUST MBR WWTP, the Jeddah WWTP’s sludge waters generally had higher DOC and biopolymer concentrations. To investigate sludge water fouling potential, the KAUST membrane tank sludge water as well as the Jeddah secondary effluent were filtrated through a membrane array consisting of an ultrafiltration (UF) Millipore RC10kDa at the first step followed by a nanofiltration (NF) KOCH Acid/Base stable NF200 at the second step. It was found that cake layer and standard blocking occurred simultaneously during both

A risk-based approach to prioritize underground storage tanks

International Nuclear Information System (INIS)

Chidambariah, V.; Travis, C.C.; Trabalka, J.R.; Thomas, J.K.

1992-01-01

The purpose of this paper is to present a risk-based approach for rapid prioritization of low level liquid radioactive waste underground storage tanks (LLLW USTs) for possible interim corrective measures and/or ultimate closure. The ranking of LLLW USTs is needed to ensure that tanks with the greatest potential for adverse impact on the environment and human health receive top priority for further evaluation and remediation. Wastes from the LLLW USTs at the Oak Ridge National Laboratory (ORNL) were pumped out at the time the tanks were removed from service. The residual liquids and sludge contain a mixture of radionuclides and chemicals. Contaminants of concern that were identified in the liquid phase of the inactive LLLW USTs include, the radionuclides, 9O Sr, 137 Cs and 233 U and the chemicals, carbon tetrachloride, trichloroethene, tetrachloroethene, methyl ethyl ketone, mercury, lead and chromium. The risk-based approach for prioritization of the LLLW USTs is based upon three major criteria: (1) leaking characteristics of the tank; (2) location of the tanks; and (3) toxic potential of the tank contents

A comparison of BNR activated sludge systems with membrane and settling tank solid-liquid separation.

Science.gov (United States)

Ramphao, M C; Wentzel, M C; Ekama, G A; Alexander, W V

2006-01-01

Installing membranes for solid-liquid separation into biological nutrient removal (BNR) activated sludge (AS) systems makes a profound difference not only to the design of the membrane bio-reactor (MBR) BNR system itself, but also to the design approach for the whole wastewater treatment plant (WWTP). In multi-zone BNR systems with membranes in the aerobic reactor and fixed volumes for the anaerobic, anoxic and aerobic zones (i.e. fixed volume fractions), the mass fractions can be controlled (within a range) with the inter-reactor recycle ratios. This zone mass fraction flexibility is a significant advantage of MBR BNR systems over BNR systems with secondary settling tanks (SSTs), because it allows changing the mass fractions to optimise biological N and P removal in conformity with influent wastewater characteristics and the effluent N and P concentrations required. For PWWF/ADWF ratios (fq) in the upper range (fq approximately 2.0), aerobic mass fractions in the lower range (f(maer) settling and long sludge age). However, the volume reduction compared with equivalent BNR systems with SSTs will not be large (40-60%), but the cost of the membranes can be offset against sludge thickening and stabilisation costs. Moving from a flow unbalanced raw wastewater system to a flow balanced (fq = 1) low (usually settled) wastewater strength system can double the ADWF capacity of the biological reactor, but the design approach of the WWTP changes away from extended aeration to include primary sludge stabilisation. The cost of primary sludge treatment then has to be offset against the savings of the increased WWTP capacity.

History of waste tank 11, 1955 through 1974

International Nuclear Information System (INIS)

Davis, T.L.; Tharin, D.W.; Lohr, D.R.

1978-10-01

Tank 11 was placed in service as a receiver of low heat waste (LW) in July 1955. In November 1961, the supernate was decanted from the sludge to prepare tank 11 for receipt of frame waste. In July 1962, the supernate was again decanted and tank 11 was used to receive fresh high heat waste (HW) from the enriched uranium process in Building 221-H. Again, the supernate was decanted in June 1965 and July 1967 to allow the tank to be reused for waste receipt. In order to use tank 11 for solid salt storage, a sludge removal operation was conducted in October 1969. The operation was unsuccessful. Tank 11 consequently received hot concentrated supernate from tank 10 blended with dilute waste and was later returned to service as a receiver of HW. A small, apparently inactive leak site was found in April 1974. Inspections have been made of the annulus and the interior of the tank both visually and with an optical periscope. Samples of the sludge, supernate, and tank vapor have been analyzed. Top-to-bottom profiles of radiation and temperature in the tank have been taken and measurements were made of deflections in the bottom knuckle plate due to changing liquid level. One horizontal and seventeen vertical cooling coils have failed, all within one month following the sludge removal operation. Several equipment modifications and various equipment repairs were made. 14 figures, 3 tables

Tank characterization report for Single-Shell Tank 241-BX-107

International Nuclear Information System (INIS)

Raphael, G.F.

1994-09-01

This study examined and assessed the status, safety issues, composition, and distribution of the wastes contained in the tank 241-BX-107. Historical and most recent information, ranging from engineering structural assessment experiments, process history, monitoring and remediation activities, to analytical core sample data, were compiled and interpreted in an effort to develop a realistic, contemporary profile for the tank BX-107 contents. The results of this is study revealed that tank BX-107, a 2,006,050 L (530,000 gal) cylindrical single-shell, dished-bottom carbon-steel tank in the 200 East Area of the Hanford Site, was classified as sound. It has been interim stabilized and thus contains less than 189,250 L (50,000 gal) of interstitial liquid, and less than 18,925 L (5,000 gal) of supernatant. It has also been partially interim isolated, whereby all inlets to the tank are sealed to prevent inadvertent addition of liquid. At a residual waste level of ∼3.07 m (120.7 ± 2 in. from sidewall bottom or ∼132.9 in. from center bottom), it is estimated that the tank BX-107 contents are equivalent to 1,305,825 L (345,000 gal). The vapor space pressure is at atmospheric. The latest temperature readings, which were taken in July 1994, show a moderate temperature value of 19 degrees C (66 degrees F). Two supernatant samples were collected in 1974 and 1990, prior to interim stabilization. Sludge core samples were obtained in 1979 and 1992

ANALYSIS OF THE LEACHING EFFICIENCY OF INHIBITED WATER AND TANK 23H SIMULANT IN REMOVING RESIDUES ON TANK 48H WALLS

International Nuclear Information System (INIS)

Fondeur, F; Thomas02 White, T; Lawrence Oji, L; Chris Martino, C; Bill Wilmarth, B

2006-01-01

Solid residues on two sets of thermowell pipe samples from the D2 riser in SRS Tank 48H were characterized. The residue thickness was determined using the ASTM standard D 3483-05 and was found to be three order of magnitudes below the 1mm thickness estimated from an earlier video of the tank cooling coil inspection. The actual estimated thickness ranged from 4 to 20.4 microns. The mass per unit area ranged from 1 to 5.3 milligrams per square inch. The residues appear to consist primarily of potassium tetraphenylborate (39.8 wt% KTPB) and dried salt solution (33.5 wt% total of nitrates, nitrites and oxalate salts), although ∼30% of the solid mass was not accounted for in the mass balance. No evidence of residue buildup was found inside the pipe, as expected. The residue leaching characteristics were measured by placing one pipe in inhibited water and one pipe in DWPF Recycle simulant. After soaking for less than 4 weeks, the inhibited water was 95.4% effective at removing the residue and the DWPF Recycle simulant was 93.5% effective. The surface appearance of the pipes after leaching tests appeared close to the clean shiny appearance of a new pipe. Total gamma counts of leachates averaged 48.1 dpm/ml, or an equivalent of 2.35E-11 Ci/gm Cs-137 (dry solids basis), which is much lower than the 1.4 E-03 Ci/gm expected for Tank 48 dry slurry solids

Tank 40 final sludge batch 9 chemical and fissile radionuclide characterization results

Energy Technology Data Exchange (ETDEWEB)

Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Kubilius, W. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pareizs, J. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-06-26

A sample of Sludge Batch (SB) 9 was pulled from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS)i. The SB9 WAPS sample was also analyzed for chemical composition, including noble metals, and fissile constituents, and these results are reported here. These analyses along with the WAPS radionuclide analyses will help define the composition of the sludge in Tank 40 that is fed to the Defense Waste Processing Facility (DWPF) as SB9. At the Savannah River National Laboratory (SRNL), the 3-L Tank 40 SB9 sample was transferred from the shipping container into a 4-L high density polyethylene bottle and solids were allowed to settle. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 547 g sub-sample was removed. This sub-sample was then utilized for all subsequent slurry sample preparations. Eight separate aliquots of the slurry were digested, four with HNO3/HCl (aqua regiaii) in sealed Teflon® vessels and four with NaOH/Na2O2 (alkali or peroxide fusioniii) using Zr crucibles. Three Analytical Reference Glass – 1iv (ARG-1) standards were digested along with a blank for each preparation. Each aqua regia digestion and blank was diluted to 1:100 with deionized water and submitted to Analytical Development (AD) for inductively coupled plasma – atomic emission spectroscopy (ICP-AES) analysis, inductively coupled plasma – mass spectrometry (ICP-MS) analysis, atomic absorption spectroscopy (AA) for As and Se, and cold vapor atomic absorption spectroscopy (CV-AA) for Hg. Equivalent dilutions of the alkali fusion digestions and blank were submitted to AD for ICP-AES analysis. Tank 40 SB9 supernate was collected from a mixed slurry sample in the SRNL Shielded Cells and submitted to AD for ICP-AES, ion chromatography (IC), total base/free OH-/other base, total inorganic

PCB extraction from ORNL tank WC-14 using a unique solvent

International Nuclear Information System (INIS)

Bloom, G.A.; Lucero, A.J.; Koran, L.J.; Turner, E.N.

1995-09-01

This report summarizes the development work of the Engineering Development Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) for an organic extraction method for removing polychlorinated biphenyls (PCBs) from tank WC-14. Tank WC-14 is part of the ORNL liquid low-level radioactive tank waste system and does not meet new secondary containment and leak detection regulations. These regulations require the tank to be taken out of service, and remediated before tank removal. To remediate the tank, the PCBs must be removed; the tank contents can then be transferred to the Melton Valley Storage Tanks before final disposal. The solvent being used for the PCB extraction experiments is triethylamine, an aliphatic amine that is soluble in water below 60 degrees F but insoluble in water above 90 degrees F. This property will allow the extraction to be carried out under fully miscible conditions within the tank; then, after tank conditions have been changed, the solvent will not be miscible with water and phase separation will occur. Phase separation between sludge, water, and solvent will allow solvent (loaded with PCBs) to be removed from the tank for disposal. After removing the PCBs from the sludge and removing the sludge from the tank, administrative control of the tank can be transferred to ORNL's Environmental Restoration Program, where priorities will be set for tank removal. Experiments with WC-14 sludge show that greater than 90% extraction efficiencies can be achieved with one extraction stage and that PCB concentration in the sludge can be reduced to below 2 ppm in three extractions. It is anticipated that three extractions will be necessary to reduce the PCB concentration to below 2 ppm during field applications. The experiments conducted with tank WC-14 sludge transferred less than 0.03% of the original alpha contamination and less than 0.002% of the original beta contamination

Metals accumulations during thermal processing of sewage sludge - characterization of bottom ash and air pollution control (APC) residues

Science.gov (United States)

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

2016-04-01

Due to increasing mass of sewage sludge, problems in its management have appeared. Over years sewage sludge was landfilled, however due to EU directives concerning environmental issues this option is no longer possible. This type of material is considered hazardous due to highly concentrated metals and harmful elements, toxic organic substances and biological components (e.g. parasites, microbes). Currently in Europe, incineration is considered to be the most reasonable method for sewage sludge treatment. As a result of sludge incineration significant amount of energy is recovered due to high calorific value of sewage sludge but bottom ash and APC residues are being produced. In this study we show the preliminary results of chemical and mineral analyses of both bottom ash and APC residues produced in fluidized bed boiler in sewage sludge incineration plant in Poland, with a special emphasis on metals which, as a part of incombustible fraction can accumulate in the residual materials after thermal processing. The bottom ash was a SiO2-P2O5-Fe2O3-CaO-Al2O3 dominated material. Main mineral phases identified in X-ray diffraction patterns were: quartz, feldspar, hematite, and phosphates (apatite and scholzite). The bottom ash was characterized by high content of Zn - 4472 mg kg-1, Cu - 665.5 mg kg-1, Pb - 138 mg kg-1, Ni - 119.5 mg kg-1, and interestingly high content of Au - 0.858 mg kg-1 The APC residues composition was dominated by soluble phases which represent more than 90% of the material. The XRD patterns indicated thenardite, halite, anhydrite, calcite and apatite as main mineral phases. The removal of soluble phases by dissolution in deionised water caused a significant mass reduction (ca. 3% of material remained on the filters). Calcite, apatite and quartz were main identified phases. The content of metals in insoluble material is relatively high: Zn - 6326 mg kg-1, Pb - 514.3 mg kg-1, Cu - 476.6 mg kg-1, Ni - 43.3 mg kg-1. The content of Cd, As, Se and Hg was

Activated Sludge and Aerobic Biofilm Reactors

OpenAIRE

Von Sperling, Marcos

2007-01-01

"Activated Sludge and Aerobic Biofilm Reactors is the fifth volume in the series Biological Wastewater Treatment. The first part of the book is devoted to the activated sludge process, covering the removal of organic matter, nitrogen and phosphorus.A detailed analysis of the biological reactor (aeration tank) and the final sedimentation tanks is provided. The second part of the book covers aerobic biofilm reactors, especially trickling filters, rotating biological contractors and submerged ae...

Determining the release of radionuclides from tank waste residual solids. FY2015 report

Energy Technology Data Exchange (ETDEWEB)

King, William D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hobbs, David T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-09-11

Methodology development for pore water leaching studies has been continued to support Savannah River Site High Level Waste tank closure efforts. For FY2015, the primary goal of this testing was the achievement of target pH and Eh values for pore water solutions representative of local groundwater in the presence of grout or grout-representative (CaCO₃ or FeS) solids as well as waste surrogate solids representative of residual solids expected to be present in a closed tank. For oxidizing conditions representative of a closed tank after aging, a focus was placed on using solid phases believed to be controlling pH and E_h at equilibrium conditions. For three pore water conditions (shown below), the target pH values were achieved to within 0.5 pH units. Tank 18 residual surrogate solids leaching studies were conducted over an E_h range of approximately 630 mV. Significantly higher Eh values were achieved for the oxidizing conditions (ORII and ORIII) than were previously observed. For the ORII condition, the target Eh value was nearly achieved (within 50 mV). However, E_h values observed for the ORIII condition were approximately 160 mV less positive than the target. E_h values observed for the RRII condition were approximately 370 mV less negative than the target. Achievement of more positive and more negative E_h values is believed to require the addition of non-representative oxidants and reductants, respectively. Plutonium and uranium concentrations measured during Tank 18 residual surrogate solids leaching studies under these conditions (shown below) followed the general trends predicted for plutonium and uranium oxide phases, assuming equilibrium with dissolved oxygen. The highest plutonium and uranium concentrations were observed for the ORIII condition and the lowest concentrations were observed for the RRII condition. Based on these results, it is recommended that these test methodologies be used to

Characterization of Solids in Residual Wastes from Single-Shell Tanks at the Hanford Site, Washington, USA - 9277

International Nuclear Information System (INIS)

Krupka, Kenneth M.; Cantrell, Kirk J.; Schaef, Herbert T.; Arey, Bruce W.; Heald, Steve M.; Deutsch, William J.; Lindberg, Michael J.

2009-01-01

Solid-phase characterization methods have been used in an ongoing study of residual wastes (i.e., waste remaining after final retrieval operations) from the underground single-shell storage tanks 241-C-103, 241-C-106, 241-C-202, 241-C-203, and 241-S-112 at the U.S. Department of Energy's Hanford Site in Washington State. The results of studies completed to date show significant variability in the compositions of those residual wastes and the compositions, morphologies, and crystallinities of the individual phases that make up these wastes. These differences undoubtedly result from the various waste types stored and transferred in and out each tank and the sluicing and retrieval operations used for waste retrieval. Our studies indicate that these residual wastes are chemically-complex assemblages of crystalline and amorphous solids that contain contaminants as discrete phases and/or co-precipitated within oxide phases. Depending on the specific tank, various solids (e.g., gibbsite; boehmite; dawsonite; cancrinite; Fe oxides such as hematite, goethite, and maghemite; rhodochrosite; lindbergite; whewellite; nitratine; and numerous amorphous or poorly crystalline phases) have been identified by X-ray diffraction and scanning electron microscopy/energy dispersive X-ray spectroscopy in residual wastes studied to date. Our studies also show that contact of residual wastes with Ca(OH)2- and CaCO3-saturated aqueous solutions, which were used as surrogates for the compositions of pore-fluid leachants derived from young and aged cements respectively, may alter the compositions of solid phases present in the contacted wastes. Fe oxides/hydroxides have been identified in all residual wastes studied to date. They occur in these wastes as discrete particles, particles intergrown within a matrix of other phases, and surface coatings on other particles or particle aggregates. These Fe oxides/hydroxides typically contain trace concentrations of other transition metals, such Cr, Mn

Colloidal agglomerates in tank sludge: Impact on waste processing. 1997 annual progress report

Energy Technology Data Exchange (ETDEWEB)

Virden, J.W.

1997-06-01

'Disposal of millions of gallons of existing radioactive wastes is a major remediation problem for the Department of Energy (DOE). Although radionuclides are the most hazardous waste con- stituents. the components of greatest concern from a waste processing standpoint are insoluble sludges consisting of submicron colloidal particles. Depending on processing conditions, these colloidal particles can form agglomerate networks that could clog transfer lines or interfere with solid-liquid separations such as settle-decant operations. Under different conditions, the particles can be dispersed to form very fine suspended particles that will not create sediment in settle- decant steps and that can foul and contaminate downstream treatment components including ion exchangers or filtrations systems. Given the wide range of tank chemistries present at Hanford and other DOE sites, it is impractical to measure the properties of all potential processing conditions to design effective treatment procedures. Instead. a framework needs to be established to allow sludge property trends to be predicted on a sound scientific basis. The scientific principles of greatest utility in characterizing, understanding, and controlling the physical properties of sludge fall in the realm of colloid chemistry. The objectives of this work are to accomplish the following: understand the factors controlling the nature and extent of colloidal agglomeration under expected waste processing conditions determine how agglomeration phenomena influence physical properties relevant to waste processing including rheology, sedimentation. and filtration develop strategies for optimizing processing conditions via control of agglomeration phenomena.'

Colloidal agglomerates in tank sludge: Impact on waste processing. 1997 annual progress report

International Nuclear Information System (INIS)

Virden, J.W.

1997-01-01

'Disposal of millions of gallons of existing radioactive wastes is a major remediation problem for the Department of Energy (DOE). Although radionuclides are the most hazardous waste constituents. the components of greatest concern from a waste processing standpoint are insoluble sludges consisting of submicron colloidal particles. Depending on processing conditions, these colloidal particles can form agglomerate networks that could clog transfer lines or interfere with solid-liquid separations such as settle-decant operations. Under different conditions, the particles can be dispersed to form very fine suspended particles that will not create sediment in settle- decant steps and that can foul and contaminate downstream treatment components including ion exchangers or filtrations systems. Given the wide range of tank chemistries present at Hanford and other DOE sites, it is impractical to measure the properties of all potential processing conditions to design effective treatment procedures. Instead. a framework needs to be established to allow sludge property trends to be predicted on a sound scientific basis. The scientific principles of greatest utility in characterizing, understanding, and controlling the physical properties of sludge fall in the realm of colloid chemistry. The objectives of this work are to accomplish the following: understand the factors controlling the nature and extent of colloidal agglomeration under expected waste processing conditions determine how agglomeration phenomena influence physical properties relevant to waste processing including rheology, sedimentation. and filtration develop strategies for optimizing processing conditions via control of agglomeration phenomena.'

Effect of the rearing tank residue of fish farms on the production of passion fruit tree seedlings

Directory of Open Access Journals (Sweden)

F. O. R. Silva

2017-03-01

Full Text Available The objective of this study was to evaluate the initial growth of seedlings and biomass production of blue and yellow passion fruit trees (round cultivar produced from residue of the rearing tanks of fish farms. The experiment was conducted in a greenhouse using residue obtained from fish farming tanks. Ravine soil (RS, fish tank residue (FR and Tropstrato (TR were used as substrate. The treatments were: T1 = control consisting of Tropstrato substrate; T2 = 25% FR + 75% RS; T3 = 50% FR + 50% RS; T4 = 25% RS + 75% FR; T5 = 100% FR. A completely randomized block design consisting of 5 treatments, 4 replicates and 11 plants per plot was used. Treatment T5 (100% fish farming residue resulted in the largest average number of leaves, highest dry matter production of the aerial part, and highest dry matter accumulation in the root (P<0.05. The worst results were obtained for the treatment using 25% FR (T2, which resulted in less uniformity of the variables studied. Stem height of the passion fruit tree was greater for the treatments that included FR, with the greatest mean height being observed for T5. In conclusion, the treatment using the residue of fish farming tanks was found to be beneficial to produce yellow passion fruit seedlings (round cultivar, representing a good alternative for the reutilization of this residue.

Critical operational parameters for zero sludge production in biological wastewater treatment processes combined with sludge disintegration.

Science.gov (United States)

Yoon, Seong-Hoon; Lee, Sangho

2005-09-01

Mathematical models were developed to elucidate the relationships among process control parameters and the effect of these parameters on the performance of anoxic/oxic biological wastewater processes combined with sludge disintegrators (A/O-SD). The model equations were also applied for analyses of activated sludge processes hybrid with sludge disintegrators (AS-SD). Solubilization ratio of sludge in the sludge disintegrator, alpha, hardly affected sludge reduction efficiencies if the biomass was completely destructed to smaller particulates. On the other hand, conversion efficiency of non-biodegradable particulates to biodegradable particulates, beta, significantly affected sludge reduction efficiencies because beta was directly related to the accumulation of non-biodegradable particulates in bioreactors. When 30% of sludge in the oxic tank was disintegrated everyday and beta was 0.5, sludge reduction was expected to be 78% and 69% for the A/O-SD and AS-SD processes, respectively. Under this condition, the sludge disintegration number (SDN), which is the amount of sludge disintegrated divided by the reduced sludge, was calculated to be around 4. Due to the sludge disintegration, live biomass concentration decreased while other non-biodegradable particulates concentration increased. As a consequence, the real F/M ratio was expected to be much higher than the apparent F/M. The effluent COD was maintained almost constant for the range of sludge disintegration rate considered in this study. Nitrogen removal efficiencies of the A/O-SD process was hardly affected by the sludge disintegration until daily sludge disintegration reaches 40% of sludge in the oxic tank. Above this level of sludge disintegration, autotrophic biomass concentration decreases overly and TKN in the effluent increases abruptly in both the A/O-SD and AS-SD processes. Overall, the trends of sludge reduction and effluent quality according to operation parameters matched well with experimental results

Derivation of residual radionuclide inventory guidelines for implace closure of high-level waste tanks

International Nuclear Information System (INIS)

Yuan, L.; Yuan, Y.

1999-01-01

Residual radionuclide inventory guidelines were derived for the high-level waste tanks at a vitrification facility. The decommissioning scenario assumed for this derivation was that the tanks were to be stabilized at the present locations and the site is released for unrestricted use following a 100-year institutional control period. It was assumed that loss of institutional control would occur at 100-years following tank closure. The derivation of the residual radionuclide inventory guidelines was based on the requirement that the effective dose equivalent (EDE) to a hypothetical individual who lives in the vicinity of the site should not exceed a dose of 0.15 mSv/yr off-site and 5 mSv/yr on-site following closure of the tanks. The RESRAD computer code, modified for exposure scenarios specific for the site, was used for this evaluation. The results of the derivation indicate that the allowable off-site dose limit will not be exceeded. The estimated potential doses to individuals using water offsite from a creek are negligibly small fractions of the 0.15 mSv/yr allowable dose limit. With an assumed 3% heel remaining in the tanks, the estimated peak dose rate for the future offsite water user is about 0.00025 mSv/yr. The residual radionuclide inventory guidelines derived based on potential doses to the on-site resident farmer indicate that, with the exception of Tc-99 and C-14, a 3% heel remaining in the tanks would not result in doses exceeding the 5 mSv/yr allowable dose limit. For this on-site exposure scenario, the peak dose rates occur at about 2000 years after tank closure. The peak dose rate is calculated to be 25 mSv/yr, with greater than 99% produced by four radionuclides: C-14, Tc-99, Np-237, and Am-241. Ingestion of contaminated vegetation contributes most (90%) of the peak dose. Since the inventories used for the derivation are mostly estimated from fuel depletion calculations. There is a need to determine further the actual inventories of these

HANFORD WASTE TANK BUMP ACCIDENT & CONSEQUENCE ANALYSIS

Energy Technology Data Exchange (ETDEWEB)

MEACHAM, J.E.

2005-02-22

Postulated physical scenarios leading to tank bumps were examined. A combination of a substantial supernatant layer depth, supernatant temperatures close to saturation, and high sludge temperatures are required for a tank bump to occur. Scenarios postulated at various times for sludge layers lacking substantial supernatant, such as superheat within the layer and fumarole formation leading to a bump were ruled out.

AX Tank Farm tank removal study

International Nuclear Information System (INIS)

SKELLY, W.A.

1998-01-01

This report considers the feasibility of exposing, demolishing, and removing underground storage tanks from the 241-AX Tank Farm at the Hanford Site. For the study, it was assumed that the tanks would each contain 360 ft 3 of residual waste (corresponding to the one percent residual Inventory target cited in the Tri-Party Agreement) at the time of demolition. The 241-AX Tank Farm is being employed as a ''strawman'' in engineering studies evaluating clean and landfill closure options for Hanford single-shell tank farms. The report is one of several reports being prepared for use by the Hanford Tanks Initiative Project to explore potential closure options and to develop retrieval performance evaluation criteria for tank farms

Effect of Sewage Sludge Addition on the Completion of Aerobic Composting of Thermally Hydrolyzed Kitchen Biogas Residue

OpenAIRE

Hong-tao Liu; Lu Cai

2014-01-01

The composting of thermal-hydrolyzed kitchen biogas residue, either with or without sewage sludge, was compared in this study. The addition of sewage sludge increased and prolonged the temperature to a sufficient level that met the requirements for aerobic composting. Moreover, after mixing the compost materials, oxygen, ammonia, and carbon dioxide levels reverted to those typical of aerobic composting. Finally, increased dewatering, organic matter degradation, and similar mature compost prod...

High-level waste tank modifications, installation of mobilization equipment/check out

International Nuclear Information System (INIS)

Schiffhauer, M.A.; Thompson, S.C.

1992-01-01

PUREX high-level waste (HLW) is contained at the West Valley Demonstration Project (WVDP) in an underground carbon-steel storage tank. The HLW consists of a precipitated sludge and an alkaline supernate. This report describes the system that the WVDP has developed and implemented to resuspend and wash the HLW sludge from the tank. The report discusses Sludge Mobilization and Wash System (SMWS) equipment design, installation, and testing. The storage tank required modifications to accommodate the SMWS. These modifications are discussed as well

Residual stress measurement on propellant tank of 2219 aluminum alloy and study on its weak spot

Energy Technology Data Exchange (ETDEWEB)

Huang, Chaoqun; Li, Huan; Li, Jianxiong; Luo, Chuanguang; Ni, Yanbing [Tianjin University, Tianjin (China)

2017-05-15

This paper presented residual stress measurement on two circumferential Variable polarity plasma arc welding (VPPAW) joints and one circular closed Friction stir welding (FSW) joint on the propellant tank of 2219 aluminum alloy using the indentation strain-gauge method. Quite large tensile residual stresses were attached to the center and inner areas of the circular closed FSW joint. There were very large tensile stresses in some points of the two circumferential VPPAW joints, among these points, the maximum value was +253 MPa, which was about 63 % of the yield strength of 410 MPa measured in the base material. In addition, the peak of compressive residual stress was about -160 MPa. Above all, there were two typical peaks of residual stress in the circumferential VPPAW joints, one was located in the middle part while the other one was near the start/end position of the joints. Combining the result of residual stress measurement with the characteristics of the tank structure, it can be concluded that circular closed FSW joint around the flange was a weak spot on the propellant tank. And the most vulnerable point on the circular closed FSW joint has also been found.

FLOWSHEET FOR ALUMINUM REMOVAL FROM SLUDGE BATCH 6

International Nuclear Information System (INIS)

Pike, J.; Gillam, J.

2008-01-01

Samples of Tank 12 sludge slurry show a substantially larger fraction of aluminum than originally identified in sludge batch planning. The Liquid Waste Organization (LWO) plans to formulate Sludge Batch 6 (SB6) with about one half of the sludge slurry in Tank 12 and one half of the sludge slurry in Tank 4. LWO identified aluminum dissolution as a method to mitigate the effect of having about 50% more solids in High Level Waste (HLW) sludge than previously planned. Previous aluminum dissolution performed in a HLW tank in 1982 was performed at approximately 85 C for 5 days and dissolved nearly 80% of the aluminum in the sludge slurry. In 2008, LWO successfully dissolved 64% of the aluminum at approximately 60 C in 46 days with minimal tank modifications and using only slurry pumps as a heat source. This report establishes the technical basis and flowsheet for performing an aluminum removal process in Tank 51 for SB6 that incorporates the lessons learned from previous aluminum dissolution evolutions. For SB6, aluminum dissolution process temperature will be held at a minimum of 65 C for at least 24 days, but as long as practical or until as much as 80% of the aluminum is dissolved. As planned, an aluminum removal process can reduce the aluminum in SB6 from about 84,500 kg to as little as 17,900 kg with a corresponding reduction of total insoluble solids in the batch from 246,000 kg to 131,000 kg. The extent of the reduction may be limited by the time available to maintain Tank 51 at dissolution temperature. The range of dissolution in four weeks based on the known variability in dissolution kinetics can range from 44 to more than 80%. At 44% of the aluminum dissolved, the mass reduction is approximately 1/2 of the mass noted above, i.e., 33,300 kg of aluminum instead of 66,600 kg. Planning to reach 80% of the aluminum dissolved should allow a maximum of 81 days for dissolution and reduce the allowance if test data shows faster kinetics. 47,800 kg of the dissolved

77 FR 12497 - Hazardous Waste Management System; Identification and Listing of Hazardous Waste Exclusion

Science.gov (United States)

2012-03-01

...,'' from the list of hazardous wastes, a maximum of 200 cubic yards per year of residual solids from sludge... accept the delisted processed storm water tank sludge. This rule also imposes testing conditions for... of F037 residual solids from processing (for oil recovery) sludge removed from two storm water tanks...

Greenhouse gases emissions accounting for typical sewage sludge digestion with energy utilization and residue land application in China

International Nuclear Information System (INIS)

Niu Dongjie; Huang Hui; Dai Xiaohu; Zhao Youcai

2013-01-01

Highlights: ► GHGs emissions from sludge digestion + residue land use in China were calculated. ► The AD unit contributes more than 97% of total biogenic GHGs emissions. ► AD with methane recovery is attractive for sludge GHGs emissions reduction. - Abstract: About 20 million tonnes of sludge (with 80% moisture content) is discharged by the sewage treatment plants per year in China, which, if not treated properly, can be a significant source of greenhouse gases (GHGs) emissions. Anaerobic digestion is a conventional sewage sludge treatment method and will continue to be one of the main technologies in the following years. This research has taken into consideration GHGs emissions from typical processes of sludge thickening + anaerobic digestion + dewatering + residue land application in China. Fossil CO 2 , biogenic CO 2 , CH 4, and avoided CO 2 as the main objects is discussed respectively. The results show that the total CO 2 -eq is about 1133 kg/t DM (including the biogenic CO 2 ), while the net CO 2 -eq is about 372 kg/t DM (excluding the biogenic CO 2 ). An anaerobic digestion unit as the main GHGs emission source occupies more than 91% CO 2 -eq of the whole process. The use of biogas is important for achieving carbon dioxide emission reductions, which could reach about 24% of the total CO 2 -eq reduction.

History of waste tank 14, 1957 through 1974

International Nuclear Information System (INIS)

Davis, T.L.; Tharin, D.W.; Jones, D.W.; Lohr, D.R.

1977-08-01

Tank 14 was placed in service as a receiver of fresh high heat waste (HW) in September 1957. Annulus leakage was discovered in April 1959 and continued until annulus ventilation was increased in January 1965. Practically all of the approximately 40 leak sites that have been identified on the tank wall are located at or below the bottom horizontal weld. Tank supernate was removed from the tank in preparation for a sludge removal operation which was performed in December 1968. The tank was then filled to its present level with blended supernate from tanks 10 and 13. In December 1972, supernate was inadvertently siphoned into the annulus through a dewatering jet, filling the annulus pan to a level of 33 in. The waste was promptly returned to the tank. Inspections of the tank interior and annulus were performed by direct observation, with a 40-ft optical periscope, and with photography and closed circuit television. Radioactive waste was first found in the annulus during visual inspection in May 1959. Samples of sludge, supernate, tank vapors, and leaked material in the annulus were analyzed, and numerous tank temperature profiles were taken. Soil and tank wall temperatures were measured in a study of tank nil ductility transition temperature. Six cooling coils failed, five of which occurred within 7 months after sludge removal. Several modifications to equipment and various equipment repairs were made. 14 figures, 3 tables

Multi-residue screening of prioritised human pharmaceuticals, illicit drugs and bactericides in sediments and sludge.

Science.gov (United States)

Langford, Katherine H; Reid, Malcolm; Thomas, Kevin V

2011-08-01

A robust multi-residue method was developed for the analysis of a selection of pharmaceutical compounds, illicit drugs and personal care product bactericides in sediments and sludges. Human pharmaceuticals were selected for analysis in Scottish sewage sludge and freshwater sediments based on prescription, physico-chemical and occurrence data. The method was suitable for the analysis of the selected illicit drugs amphetamine, benzoylecgonine, cocaine, and methamphetamine, the pharmaceuticals atenolol, bendroflumethiazide, carbamazepine, citalopram, diclofenac, fluoxetine, ibuprofen, and salbutamol, and the bactericides triclosan and triclocarban in sewage sludge and freshwater sediment. The method provided an overall recovery of between 56 and 128%, RSDs of between 2 and 19% and LODs of between 1 and 50 ng g(-1). Using the methodology the human pharmaceuticals atenolol, carbamazepine and citalopram and the bactericides triclosan and triclocarban were detected in Scottish sewage sludge. The illicit drugs cocaine, its metabolite benzoylecgonine, amphetamine and methamphetamine were not detected in any of the samples analysed. Triclosan and triclocarban were present at the highest concentrations with triclocarban detected in all but one sample and showing a pattern of co-occurrence in both sludge and sediment samples.

Fate of antibiotic and metal resistance genes during two-phase anaerobic digestion of residue sludge revealed by metagenomic approach.

Science.gov (United States)

Wu, Ying; Cui, Erping; Zuo, Yiru; Cheng, Weixiao; Chen, Hong

2018-03-07

The prevalence and persistence of antibiotic resistance genes in wastewater treatment plants (WWTPs) is of growing interest, and residual sludge is among the main sources for the release of antibiotic resistance genes (ARGs). Moreover, heavy metals concentrated in dense microbial communities of sludge could potentially favor co-selection of ARGs and metal resistance genes (MRGs). Residual sludge treatment is needed to limit the spread of resistance from WWTPs into the environment. This study aimed to explore the fate of ARGs and MRGs during thermophilic two-phase (acidogenic/methanogenic phase) anaerobic digestion by metagenomic analysis. The occurrence and abundance of mobile genetic elements were also determined based on the SEED database. Among the 27 major ARG subtypes detected in feed sludge, large reductions (> 50%) in 6 ARG subtypes were achieved by acidogenic phase (AP), while 63.0% of the ARG subtypes proliferated in the following methanogenic phase (MP). In contrast, a 2.8-fold increase in total MRG abundance was found in AP, while the total abundance during MP decreased to the same order of magnitude as in feed sludge. The distinct dynamics of ARGs and MRGs during the two-phase anaerobic digestion are noteworthy, and more specific treatments are required to limit their proliferation in the environment.

Sludge Settling Rate Observations and Projections at the Savannah River Site - 13238

Energy Technology Data Exchange (ETDEWEB)

Gillam, Jeffrey M.; Shah, Hasmukh B.; Keefer, Mark T. [Savannah River Remediation LLC, Aiken SC 29808 (United States)

2013-07-01

Since 2004, sludge batches have included a high percentage of stored sludge generated from the H- modified (HM) process. The slow-settling nature of HM sludge means that the settling is often the major part of the washing tank quiescent period between required pump runs to maintain flammability control. Reasonable settling projections are needed to wash soluble salts from sludge in an efficient manner, to determine how much sludge can be washed in a batch within flammability limits, and to provide composition projections for batch qualification work done in parallel with field preparation. Challenges to providing reasonably accurate settling projections include (1) large variations in settling behavior from tank-to-tank, (2) accounting for changing initial concentrations, sludge masses, and combinations of different sludge types, (3) changing the settling behavior upon dissolving some sludge compounds, and (4) sludge preparation schedules that do not allow for much data collection for a particular sludge before washing begins. Scaling from laboratory settling tests has provided inconsistent results. Several techniques have been employed to improve settling projections and therefore the overall batch preparation efficiency. Before any observations can be made on a particular sludge mixture, projections can only be made based on historical experience with similar sludge types. However, scaling techniques can be applied to historical settling models to account for different sludge masses, concentrations, and even combinations of types of sludge. After sludge washing/settling cycles begin, the direct measurement of the sludge height, once generally limited to a single turbidity meter measurement per settle period, is now augmented by examining the temperature profile in the settling tank, to help determine the settled sludge height over time. Recently, a settling model examined at PNNL [1,2,3] has been applied to observed thermocouple and turbidity meter readings to

Computer modeling of jet mixing in INEL waste tanks

International Nuclear Information System (INIS)

Meyer, P.A.

1994-01-01

The objective of this study is to examine the feasibility of using submerged jet mixing pumps to mobilize and suspend settled sludge materials in INEL High Level Radioactive Waste Tanks. Scenarios include removing the heel (a shallow liquid and sludge layer remaining after tank emptying processes) and mobilizing and suspending solids in full or partially full tanks. The approach used was to (1) briefly review jet mixing theory, (2) review erosion literature in order to identify and estimate important sludge characterization parameters (3) perform computer modeling of submerged liquid mixing jets in INEL tank geometries, (4) develop analytical models from which pump operating conditions and mixing times can be estimated, and (5) analyze model results to determine overall feasibility of using jet mixing pumps and make design recommendations

Tank characterization report for single-shell tank 241-B-104

International Nuclear Information System (INIS)

Field, J.G.

1996-01-01

This document summarizes information on the historical uses, present status, and the sampling and analysis results of waste stored in Tank 241-B-104. Sampling and analyses meet safety screening and historical data quality objectives. This report supports the requirements of Tri-party Agreement Milestone M-44-09. his characterization report summoned the available information on the historical uses and the current status of single-shell tank 241-B-104, and presents the analytical results of the June 1995 sampling and analysis effort. This report supports the requirements of the Hanford Federal Facility Agreement and Consent Order Milestone M-44-09 (Ecology et al. 1994). Tank 241-B-104 is a single-shell underground waste storage tank located in the 200 East Area B Tank Farm on the Hanford Site. It is the first tank in a three-tank cascade series. The tank went into service in August 1946 with a transfer of second-cycle decontamination waste generated from the bismuth phosphate process. The tank continued to receive this waste type until the third quarter of 1950, when it began receiving first-cycle decontamination waste also produced during the bismuth phosphate process. Following this, the tank received evaporator bottoms sludge from the 242-B Evaporator and waste generated from the flushing of transfer lines. A description and the status of tank 241-B-104 are sum in Table ES-1 and Figure ES-1. The tank has an operating capacity of 2,010 kL (530 kgal), and presently contains 1,400 kL (371 kgal) of waste. The total amount is composed of 4 kL (1 kgal) of supernatant, 260 kL (69 kgal) of saltcake, and 1,140 kL (301 kgal) of sludge (Hanlon 1995). Current surveillance data and observations appear to support these results

Hanford Sludge Simulant Selection for Soil Mechanics Property Measurement

Energy Technology Data Exchange (ETDEWEB)

Wells, Beric E.; Russell, Renee L.; Mahoney, Lenna A.; Brown, Garrett N.; Rinehart, Donald E.; Buchmiller, William C.; Golovich, Elizabeth C.; Crum, Jarrod V.

2010-03-23

The current System Plan for the Hanford Tank Farms uses relaxed buoyant displacement gas release event (BDGRE) controls for deep sludge (i.e., high level waste [HLW]) tanks, which allows the tank farms to use more storage space, i.e., increase the sediment depth, in some of the double-shell tanks (DSTs). The relaxed BDGRE controls are based on preliminary analysis of a gas release model from van Kessel and van Kesteren. Application of the van Kessel and van Kesteren model requires parametric information for the sediment, including the lateral earth pressure at rest and shear modulus. No lateral earth pressure at rest and shear modulus in situ measurements for Hanford sludge are currently available. The two chemical sludge simulants will be used in follow-on work to experimentally measure the van Kessel and van Kesteren model parameters, lateral earth pressure at rest, and shear modulus.

Hanford Sludge Simulant Selection for Soil Mechanics Property Measurement

International Nuclear Information System (INIS)

Wells, Beric E.; Russell, Renee L.; Mahoney, Lenna A.; Brown, Garrett N.; Rinehart, Donald E.; Buchmiller, William C.; Golovich, Elizabeth C.; Crum, Jarrod V.

2010-01-01

The current System Plan for the Hanford Tank Farms uses relaxed buoyant displacement gas release event (BDGRE) controls for deep sludge (i.e., high level waste (HLW)) tanks, which allows the tank farms to use more storage space, i.e., increase the sediment depth, in some of the double-shell tanks (DSTs). The relaxed BDGRE controls are based on preliminary analysis of a gas release model from van Kessel and van Kesteren. Application of the van Kessel and van Kesteren model requires parametric information for the sediment, including the lateral earth pressure at rest and shear modulus. No lateral earth pressure at rest and shear modulus in situ measurements for Hanford sludge are currently available. The two chemical sludge simulants will be used in follow-on work to experimentally measure the van Kessel and van Kesteren model parameters, lateral earth pressure at rest, and shear modulus.

Counter current decantation washing of HLW sludge

International Nuclear Information System (INIS)

Brooke, J.N.; Peterson, R.A.

1997-01-01

The Savannah River Site (SRS) has 51 High Level Waste (HLW) tanks with typical dimensions 25.9 meters (85 feet) diameter and 10 meters (33 feet) high. Nearly 114 million liters (30 M gallons) of HLW waste is stored in these tanks in the form of insoluble solids called sludge, crystallized salt called salt cake, and salt solutions. This waste is being converted to waste forms stable for long term storage. In one of the processes, soluble salts are washed from HLW sludge in preparation for vitrification. At present, sludge is batch washed in a waste tank with one or no reuse of the wash water. Sodium hydroxide and sodium nitrite are added to the wash water for tank corrosion protection; the large volumes of spent wash water are recycled to the evaporator system; additional salt cake is produced; and sodium carbonate is formed in the washed sludge during storage by reaction with CO 2 from the air. High costs and operational concerns with the current washing process prompts DOE and WSRC to seek an improved washing method. A new method should take full advantage of the physical/chemical properties of sludge, experience from other technical disciplines, processing rate requirements, inherent process safety, and use of proven processes and equipment. Counter current solids washing is a common process in the minerals processing and chemical industries. Washing circuits can be designed using thickeners, filters or centrifuges. Realizing the special needs of nuclear work and the low processing rates required, a Counter Current Decantation (CCD) circuit is proposed using small thickeners and fluidic pumps

Tank 21 and Tank 24 Blend and Feed Study: Blending Times, Settling Times, and Transfers

International Nuclear Information System (INIS)

Lee, S.; Leishear, R.; Poirier, M.

2012-01-01

The Salt Disposition Integration (SDI) portfolio of projects provides the infrastructure within existing Liquid Waste facilities to support the startup and long term operation of the Salt Waste Processing Facility (SWPF). Within SDI, the Blend and Feed Project will equip existing waste tanks in the Tank Farms to serve as Blend Tanks where salt solutions of up to 1.2 million gallons will be blended in 1.3 million gallon tanks and qualified for use as feedstock for SWPF. In particular, Tanks 21 and 24 are planned to be used for blending and transferring to the SDI feed tank. These tanks were evaluated here to determine blending times, to determine a range of settling times for disturbed sludge, and to determine that the SWPF Waste Acceptance Criteria that less than 1200 mg/liter of solids will be entrained in salt solutions during transfers from the Tank 21 and Tank 24 will be met. Overall conclusions for Tank 21 and Tank 24 operations include: (1) Experimental correction factors were applied to CFD (computational fluid dynamics) models to establish blending times between approximately two and five hours. As shown in Phase 2 research, blending times may be as much as ten times greater, or more, if lighter fluids are added to heavier fluids (i.e., water added to salt solution). As the densities of two salt solutions converge this effect may be minimized, but additional confirmatory research was not performed. (2) At the current sludge levels and the presently planned operating heights of the transfer pumps, solids entrainment will be less than 1200 mg/liter, assuming a conservative, slow settling sludge simulant. (3) Based on theoretical calculations, particles in the density range of 2.5 to 5.0 g/mL must be greater than 2-4 (micro)m in diameter to ensure they settle adequately in 30-60 days to meet the SWPF feed criterion ( 60 days) settling times in Tank 21.

Development of an efficient anaerobic co-digestion process for garbage, excreta, and septic tank sludge to create a resource recycling-oriented society.

Science.gov (United States)

Sun, Zhao-Yong; Liu, Kai; Tan, Li; Tang, Yue-Qin; Kida, Kenji

2017-03-01

In order to develop a resource recycling-oriented society, an efficient anaerobic co-digestion process for garbage, excreta and septic tank sludge was studied based on the quantity of each biomass waste type discharged in Ooki machi, Japan. The anaerobic digestion characteristics of garbage, excreta and 5-fold condensed septic tank sludge (hereafter called condensed sludge) were determined separately. In single-stage mesophilic digestion, the excreta with lower C/N ratios yielded lower biogas volumes and accumulated higher volumes of volatile fatty acid (VFA). On the other hand, garbage allowed for a significantly larger volatile total solid (VTS) digestion efficiency as well as biogas yield by thermophilic digestion. Thus, a two-stage anaerobic co-digestion process consisting of thermophilic liquefaction and mesophilic digestion phases was proposed. In the thermophilic liquefaction of mixed condensed sludge and household garbage (wet mass ratio of 2.2:1), a maximum VTS loading rate of 24g/L/d was achieved. In the mesophilic digestion of mixed liquefied material and excreta (wet mass ratio of 1:1), biogas yield reached approximately 570ml/g-VTS fed with a methane content of 55% at a VTS loading rate of 1.0g/L/d. The performance of the two-stage process was evaluated by comparing it with a single-stage process in which biomass wastes were treated separately. Biogas production by the two-stage process was found to increase by approximately 22.9%. These results demonstrate the effectiveness of a two-stage anaerobic co-digestion process in enhancement of biogas production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Greenhouse gases emissions accounting for typical sewage sludge digestion with energy utilization and residue land application in China

Energy Technology Data Exchange (ETDEWEB)

Niu Dongjie, E-mail: niudongjie@tongji.edu.cn [Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of Environmental Science and Engineering of Tongji University, 1239 Siping Road, Shanghai 200092 (China); UNEP-Tongji Institute of Environment for Sustainable Development, 1239 Siping Road, Shanghai 200092 (China); Huang Hui [Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of Environmental Science and Engineering of Tongji University, 1239 Siping Road, Shanghai 200092 (China); Dai Xiaohu [Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of Environmental Science and Engineering of Tongji University, 1239 Siping Road, Shanghai 200092 (China); National Engineering Research Center for Urban Pollution Control, Shanghai 200092 (China); Zhao Youcai [Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, College of Environmental Science and Engineering of Tongji University, 1239 Siping Road, Shanghai 200092 (China)

2013-01-15

Highlights: Black-Right-Pointing-Pointer GHGs emissions from sludge digestion + residue land use in China were calculated. Black-Right-Pointing-Pointer The AD unit contributes more than 97% of total biogenic GHGs emissions. Black-Right-Pointing-Pointer AD with methane recovery is attractive for sludge GHGs emissions reduction. - Abstract: About 20 million tonnes of sludge (with 80% moisture content) is discharged by the sewage treatment plants per year in China, which, if not treated properly, can be a significant source of greenhouse gases (GHGs) emissions. Anaerobic digestion is a conventional sewage sludge treatment method and will continue to be one of the main technologies in the following years. This research has taken into consideration GHGs emissions from typical processes of sludge thickening + anaerobic digestion + dewatering + residue land application in China. Fossil CO{sub 2}, biogenic CO{sub 2}, CH{sub 4,} and avoided CO{sub 2} as the main objects is discussed respectively. The results show that the total CO{sub 2}-eq is about 1133 kg/t DM (including the biogenic CO{sub 2}), while the net CO{sub 2}-eq is about 372 kg/t DM (excluding the biogenic CO{sub 2}). An anaerobic digestion unit as the main GHGs emission source occupies more than 91% CO{sub 2}-eq of the whole process. The use of biogas is important for achieving carbon dioxide emission reductions, which could reach about 24% of the total CO{sub 2}-eq reduction.

Production of hydrogen in a granular sludge-based anaerobic continuous stirred tank reactor

Energy Technology Data Exchange (ETDEWEB)

Show, Kuan-Yeow [Faculty of Engineering and Science, University of Tunku Abdul Rahman, 53300 Setapak, Kuala Lumpur (Malaysia); Zhang, Zhen-Peng; Tay, Joo-Hwa [School of Civil and Environmental Engineering, Nanyang Technological University, 639798 (Singapore); Institute of Environmental Science and Engineering, Nanyang Technological University, 637723 (Singapore); Tee Liang, David [Institute of Environmental Science and Engineering, Nanyang Technological University, 637723 (Singapore); Lee, Duu-Jong [Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan, RO (China); Jiang, Wen-Ju [Department of Environmental Science and Engineering, Sichuan University, Chengdu 610065 (China)

2007-12-15

An investigation on biohydrogen production was conducted in a granular sludge-based continuous stirred tank reactor (CSTR). The reactor performance was assessed at five different glucose concentrations of 2.5, 5, 10, 20 and 40 g/L and four hydraulic retention times (HRTs) of 0.25, 0.5, 1 and 2 h, resulting in the organic loading rates (OLRs) ranged between 2.5 and 20 g-glucose/L h. Carbon flow was traced by analyzing the composition of gaseous and soluble metabolites as well as the cell yield. Butyrate, acetate and ethanol were found to be the major soluble metabolite products in the biochemical synthesis of hydrogen. Carbon balance analysis showed that more than half of the glucose carbon was converted into unidentified soluble products at an OLR of 2.5 g-glucose/L h. It was found that high hydrogen yields corresponded to a sludge loading rate in between 0.6 and 0.8 g-glucose/g-VSS h. Substantial suppression in hydrogen yield was noted as the sludge loading rate fell beyond the optimum range. It is deduced that decreasing the sludge loading rate induced the metabolic shift of biochemical reactions at an OLR of 2.5 g-glucose/L h, which resulted in a substantial reduction in hydrogen yield to 0.36-0.41 mol-H{sub 2}/mol-glucose. Optimal operation conditions for peak hydrogen yield (1.84 mol-H{sub 2}/mol-glucose) and hydrogen production rate (3.26 L/L h) were achieved at an OLR of 20 g-glucose/L h, which corresponded to an HRT of 0.5 h and an influent glucose concentration of 10 g/L. Influence of HRT and substrate concentration on the reactor performance was interrelated and the adverse impact on hydrogen production was noted as substrate concentration was higher than 20 g/L or HRT was shorter than 0.5 h. The experimental study indicated that a higher OLR derived from appropriate HRTs and substrate concentrations was desirable for hydrogen production in such a granule-based CSTR. (author)

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

International Nuclear Information System (INIS)

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

1998-01-01

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

Influence of secondary settling tank performance on suspended solids mass balance in activated sludge systems.

Science.gov (United States)

Patziger, M; Kainz, H; Hunze, M; Józsa, J

2012-05-01

Secondary settling is the final step of the activated sludge-based biological waste water treatment. Secondary settling tanks (SSTs) are therefore an essential unit of producing a clear effluent. A further important function of SSTs is the sufficient thickening to achieve highly concentrated return sludge and biomass within the biological reactor. In addition, the storage of activated sludge is also needed in case of peak flow events (Ekama et al., 1997). Due to the importance of a high SST performance the problem has long been investigated (Larsen, 1977; Krebs, 1991; Takács et al., 1991; Ekama et al., 1997; Freimann, 1999; Patziger et al., 2005; Bürger et al., 2011), however, a lot of questions are still to solve regarding e.g. the geometrical features (inflow, outflow) and operations (return sludge control, scraper mechanism, allowable maximum values of surface overflow rates). In our study we focused on SSTs under dynamic load considering both the overall unsteady behaviour and the features around the peaks, investigating the effect of various sludge return strategies as well as the inlet geometry on SST performance. The main research tool was a FLUENT-based novel mass transport model consisting of two modules, a 2D axisymmetric SST model and a mixed reactor model of the biological reactor (BR). The model was calibrated and verified against detailed measurements of flow and concentration patterns, sludge settling, accompanied with continuous on-line measurement of in- and outflow as well as returned flow rates of total suspended solids (TSS) and water. As to the inlet arrangement a reasonable modification of the geometry could result in the suppression of the large scale flow structures of the sludge-water interface thus providing a significant improvement in the SST performance. Furthermore, a critical value of the overflow rate (q(crit)) was found at which a pronounced large scale circulation pattern develops in the vertical plane, the density current in

Underground storage tank soft waste dislodging and conveyance

International Nuclear Information System (INIS)

Wellner, A.F.S.

1993-01-01

The primary objective of this task is to demonstrate potential technical solutions and to acquire engineering data and information on the retrieval technologies applicable for use in retrieving waste from underground storage tanks. This task focuses on soft waste dislodging and conveyance technologies that would be used in conjunction with a manipulator-based retrieval system. This retrieval task focuses on Hanford single-shell tanks, but the results may also have applications to other waste retrieval problems. This work is part of the U.S. Department of Energy's (DOE's) Office of Technology Development, sponsored by the DOE's Richland Operations Office under the Underground Storage Tanks Integrated Demonstration (USTID) program. This task is one element of the whole waste dislodging and conveyance system in the USTID. The tank wastes contain both hazardous and radioactive constituents. This task focuses on the processes for dislodging and retrieving soft wastes, mainly sludge. Sludge consists primarily of heavy-metal, iron, and aluminum precipitates. Sludges vary greatly in their physical properties and may contain pockets of liquid. Sludges have been described as varying in consistency from thick slurry to sticky clay and as sandy with hard chunks of material. The waste is believed to have adhesive and cohesive properties. The quantitative physical properties of the wastes have yet to be measured. The waste simulants used in the testing program emulate the physical properties of the tank waste

Radioactive sludge and wastewater analysis and treatment in the Hungarian VVER-440/213-type NPP

International Nuclear Information System (INIS)

Patzay, G.; Weiser, L.; Feil, F.; Schunk, J.; Patek, G.; Pinter, T.

2010-01-01

It is well known that in the Hungarian VVER-type nuclear power plant Paks the radioactive waste waters are collected in common tanks. These water streams contain radioactive isotopes in ultra-low concentration and inactive compounds as major components (borate 1.7 g/dm 3 , sodium-nitrate 0.4 g/dm 3 , sodium-hydroxide 0.16 g/dm 3 , and oxalate 0.25 g/dm 3 ). These low salinity solutions were evaporated by adding sodium-hydroxide, until 400 g/dm 3 salt content is reached. There is about 6000 m 3 concentrated evaporator bottom residues in the tanks of the reactor. There are some tanks at the power plant containing sludge type radioactive waste containing more or less liquid phase too. The general physical and chemical characteristics (density, pH, total solid, dissolved solid etc.) and chemical and radiochemical composition are important information for volume reduction and solidification treatment of these wastes. We have investigated and constructed a complex analysis system for the radioactive sludge and supernatant analysis, including the physical, as well as the chemical and radiochemical analysis methods. Using well known analysis techniques as ion chromatography, ICP-MS, AAS, gamma-and alpha-spectrometry and chemical alkaline fusion digestion and acidic dissolution methods we could analyze the main inorganic, organic and radioactive components of the sludges and supernatants. Determination of the mass and charge balance for the sludge samples were more difficult then for the supernatant samples. Not only are there assumptions required about the chemical form and the oxidation state of the species present in the sludge, but many of the compounds in the sludge are mixed oxides which are not directly measured. Also, the sludge is actually a slurry with a high water content. The interstitial liquid is in close contact with the sludge, and there are many ionic solubility equilibriums. The anion data for the sludge samples are based on the water soluble anions that

Summary review of the chemical characterization of liquid and sludge contained in the Old Hydrofracture tanks, Oak Ridge National Laboratory, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

Francis, C.W.; Herbes, S.E.

1997-02-01

This report presents analytical data developed from samples collected from the five inactive tanks located at the Old Hydrofracture Facility (OHF) at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The samples were collected during December 1995 and January 1996. The purpose of the sampling and analysis project was (1) to determine whether the tank contents meet ORNL waste acceptance criteria, as specified in the Oak Ridge National Laboratory, Liquid Waste Treatment Systems, Waste Evaluation Criteria; (2) to determine various physical properties of the tank contents that would affect the design of a sludge mobilization system; and (3) to gather information to support a baseline risk assessment. The report focuses on the analytical results used to evaluate the tank contents with regard to nuclear criticality safety requirements and to regulatory waste characterization

Sludge treatment facility preliminary siting study for the sludge treatment project (A-13B)

International Nuclear Information System (INIS)

WESTRA, A.G.

1999-01-01

This study evaluates various sites in the 100 K area and 200 areas of Hanford for locating a treatment facility for sludge from the K Basins. Both existing facilities and a new standalone facility were evaluated. A standalone facility adjacent to the AW Tank Farm in the 200 East area of Hanford is recommended as the best location for a sludge treatment facility

Study of radionuclide leaching from the residues of K Basin sludge dissolution

International Nuclear Information System (INIS)

Bechtold, D.B.

1998-01-01

The sludges remaining in the K Basins after removal of the spent N Reactor nuclear fuel will be conditioned for disposal. After conditioning, an acid-insoluble residue will remain that may require further leaching to properly condition it for disposal. This document presents a literature study to identify and recommend one or more chemical leaching treatments for laboratory testing, based on the likely compositions of the residues. The processes identified are a nitric acid cerate leach, a silver-catalyzed persulfate leach, a nitric hydrofluoric acid leach, an oxalic citric acid reactor decontamination leach, a nitric hydrochloric acid leach, a ammonium fluoride nitrate leach, and a HEOPA formate dehydesulfoxylate leach. All processes except the last two are recommended for testing in that order

Tank waste treatment science task quarterly report, April 1995--June 1995

International Nuclear Information System (INIS)

LaFemina, J.P.

1995-07-01

This report describes the work performed by the Pacific Northwest Laboratory (PNL) during the third quarter of FY 1995 under the Tank Waste Treatment Science Task of the Tank Waste Remediation System (TWRS) Pretreatment Technology Development Project. Work was performed in the following areas: (1) analytical methods development, (2) sludge dissolution modeling, (3) sludge characterization studies, (4) sludge component speciation, (5) pretreatment chemistry evaluation, and (6) colloidal studies for solid-liquid separations

Grey-box modelling of aeration tank settling.

Science.gov (United States)

Bechman, Henrik; Nielsen, Marinus K; Poulsen, Niels Kjølstad; Madsen, Henrik

2002-04-01

A model of the concentrations of suspended solids (SS) in the aeration tanks and in the effluent from these during Aeration tank settling (ATS) operation is established. The model is based on simple SS mass balances, a model of the sludge settling and a simple model of how the SS concentration in the effluent from the aeration tanks depends on the actual concentrations in the tanks and the sludge blanket depth. The model is formulated in continuous time by means of stochastic differential equations with discrete-time observations. The parameters of the model are estimated using a maximum likelihood method from data from an alternating BioDenipho waste water treatment plant (WWTP). The model is an important tool for analyzing ATS operation and for selecting the appropriate control actions during ATS, as the model can be used to predict the SS amounts in the aeration tanks as well as in the effluent from the aeration tanks.

Process chemistry for the pretreatment of Hanford tank wastes

International Nuclear Information System (INIS)

Lumetta, G.J.; Swanson, J.L.; Barker, S.A.

1992-08-01

Current guidelines for disposing radioactive wastes stored in underground tanks at the US Department of Energy's Hanford Site call for the vitrification of high-level waste in borosilicate glass and disposal of the glass canisters in a deep geologic repository. Low-level waste is to be cast in grout and disposed of on site in shallow burial vaults. Because of the high cost of vitrification and geologic disposal, methods are currently being developed to minimize the volume of high-level waste requiring disposal. Two approaches are being considered for pretreating radioactive tank sludges: (1) leaching of selected components from the sludge and (2) acid dissolution of the sludge followed by separation of key radionuclides. The leaching approach offers the advantage of simplicity, but the acid dissolution/radionuclide extraction approach has the potential to produce the least number of glass canisters. Four critical components (Cr, P, S, and Al) were leached from an actual Hanford tank waste-Plutonium Finishing Plant sludge. The Al, P, and S were removed from the sludge by digestion of the sludge with 0.1 M NaOH at 100 degrees C. The Cr was leached by treating the sludge with alkaline KMnO 4 at 100 degrees C. Removing these four components from the sludge will dramatically lower the number of glass canisters required to dispose of this waste. The transuranic extraction (TRUEX) solvent extraction process has been demonstrated at a bench scale using an actual Hanford tank waste. The process, which involves extraction of the transuranic elements with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO), separated 99.9% of the transuranic elements from the bulk components of the waste. Several problems associated with the TRUEX processing of this waste have been addressed and solved

Evaluation of Flygt Propeller Mixers for Double-Shell Tank (DST) High Level Waste Auxiliary Solids Mobilization

International Nuclear Information System (INIS)

PACQUET, E.A.

2000-01-01

The River Protection Project (RPP) is planning to retrieve radioactive waste from the single-shell tanks (SST) and double-shell tanks (DST) underground at the Hanford Site. This waste will then be transferred to a waste treatment plant to be immobilized (vitrified) in a stable glass form. Over the years, the waste solids in many of the tanks have settled to form a layer of sludge at the bottom. The thickness of the sludge layer varies from tank to tank, from no sludge or a few inches of sludge to about 15 ft of sludge. The purpose of this technology and engineering case study is to evaluate the Flygt(trademark) submersible propeller mixer as a potential technology for auxiliary mobilization of DST HLW solids. Considering the usage and development to date by other sites in the development of this technology, this study also has the objective of expanding the knowledge base of the Flygt(trademark) mixer concept with the broader perspective of Hanford Site tank waste retrieval. More specifically, the objectives of this study delineated from the work plan are described

Evaluation of Flygt Propeller Xixers for Double Shell Tank (DST) High Level Waste Auxiliary Solids Mobilization

Energy Technology Data Exchange (ETDEWEB)

PACQUET, E.A.

2000-07-20

The River Protection Project (RPP) is planning to retrieve radioactive waste from the single-shell tanks (SST) and double-shell tanks (DST) underground at the Hanford Site. This waste will then be transferred to a waste treatment plant to be immobilized (vitrified) in a stable glass form. Over the years, the waste solids in many of the tanks have settled to form a layer of sludge at the bottom. The thickness of the sludge layer varies from tank to tank, from no sludge or a few inches of sludge to about 15 ft of sludge. The purpose of this technology and engineering case study is to evaluate the Flygt{trademark} submersible propeller mixer as a potential technology for auxiliary mobilization of DST HLW solids. Considering the usage and development to date by other sites in the development of this technology, this study also has the objective of expanding the knowledge base of the Flygt{trademark} mixer concept with the broader perspective of Hanford Site tank waste retrieval. More specifically, the objectives of this study delineated from the work plan are described.

K Basin Sludge Conditioning Process Testing Fate of PCBs During K Basin Sludge Dissolution in Nitric Acid and with Hydrogen Peroxide Addition

International Nuclear Information System (INIS)

Schmidt, A.J.; Thornton, B.M.; Hoppe, E.W.; Mong, G.M.; Pool, K.H.; Silvers, K.L.

1999-01-01

The work described in this report is part of the studies being performed to address the fate of polychlorinated biphenyls (PCBs) in K Basin sludge before the sludge can be transferred to the Tank Waste Remediation System (TWRS) double shell tanks. One set of tests examined the effect of hydrogen peroxide on the disposition of PCBs in a simulated K Basin dissolver solution containing 0.5 M nitric acid/1 M Fe(NO 3 ) 3 . A second series of tests examined the disposition of PCBs in a much stronger (∼10 M) nitric acid solution, similar to that likely to be encountered in the dissolution of the sludge

Level trend analysis summary report for Oak Ridge National Laboratory inactive liquid low-level waste tanks

International Nuclear Information System (INIS)

1994-09-01

Oak Ridge National Laboratory facilities have produced liquid low-level waste (LLLW) that is radioactive and/or hazardous. Storage tanks have been used to collect and store these wastes. Most of the collection system, including the tanks, is located below the ground surface. Many of the systems have been removed from service (i.e., are not inactive) but contain residual amounts of waste liquid and sludges. A plan of action has been developed by DOE to ensure that environmental impacts from the waste remaining in the inactive tanks system are minimized. The Federal Facility Agreement (FFA) does not require any type of testing or monitoring for the inactive LLLW tanks that are removed from service but does require waste characterization of tanks contents, risk characterization of tanks removed from service, and remediation of the inactive tanks and their contents. This report is form information only and is not required by the FFA. It includes a description of the methodology and results of level trend analyses for the Category D tanks listed in the FFA that currently belong to the Environmental Restoration Program

Dimethyl sulfoxide (DMSO) waste residues and municipal waste water odor by dimethyl sulfide (DMS): the north-east WPCP plant of Philadelphia.

Science.gov (United States)

Glindemann, Dietmar; Novak, John; Witherspoon, Jay

2006-01-01

This study shows for the first time that overlooked mg/L concentrations of industrial dimethyl sulfoxide (DMSO) waste residues in sewage can cause "rotten cabbage" odor problems bydimethyl sulfide (DMS) in conventional municipal wastewater treatment. In laboratory studies, incubation of activated sludge with 1-10 mg/L DMSO in bottles produced dimethyl sulfide (DMS) at concentrations that exceeded the odor threshold by approximately 4 orders of magnitude in the headspace gas. Aeration at a rate of 6 m3 air/m3 sludge resulted in emission of the DMS into the exhaust air in a manner analogous to that of an activated sludge aeration tank. A field study atthe NEWPCP sewage treatment plant in Philadelphia found DMSO levels intermittently peaking as high as 2400 mg/L in sewage near an industrial discharger. After 3 h, the DMSO concentration in the influent to the aeration tank rose from a baseline level of less than 0.01 mg/L to a level of 5.6 mg/L and the DMS concentration in the mixed liquor rose from less than 0.01 to 0.2 mg/L. Finding this link between the intermittent occurrence of DMSO residues in influent of the treatment plant and the odorant DMS in the aeration tank was the keyto understanding and eliminating the intermittent "canned corn" or "rotten cabbage" odor emissions from the aeration tank that had randomly plagued this plant and its city neighborhood for two decades. Sewage authorities should consider having wastewater samples analyzed for DMSO and DMS to check for this possible odor problem and to determine whether DMSO emission thresholds should be established to limit odor generation at sewage treatment plants.

Effects of Sludge Dry Solid Content and Residual Bulking Agents on Volatile Solids Reduction Using Eisenia foetida

Directory of Open Access Journals (Sweden)

Mohammad ali Abdoli

2009-06-01

Full Text Available In the first stage of this study, the compound effects of sludge dry solid content and residual bulking agent type (paper, saw dust, straw mixed with activated sludge (10, 15, and 20% dry solids on volatile solids (V.S. reduction were investigated using Eisenia foetida in pilot scale experiments with batches of fifty earthworms in each of the 10 experimental treatments over a period of 10 weeks. The maximum V.S. reduction was attained in the mixture of sludge and paper, with a D.S. of 15% (0.42 ± 0.03 % day-1 while the minimum V.S. reduction was achieved in the mixture of sludge and straw, with a D.S. of 10% (0.26 ± 0.01 % day-1. In the second stage, the survival of Eisenia foetida in the anaerobic sewage sludge was investigated. In the unmixed raw anaerobic sludge, all the earthworms died during the first 9 weeks of the study period due to acute toxicity. From week 10, however, their survival rate improved so that by week 12 when toxicity reduced to 25.40%, they completely survived. This is while in the mixture of anaerobic sludge with paper (D.S. 15%, 100% of the earthworms survived from week 8 after the volatile solids reduced to 20.42% and 17.40%.

Computational Fluid Dynamics Modelling of Hydraulics and Sedimentation in Process Reactors during Aeration Tank Settling

DEFF Research Database (Denmark)

Jensen, M.D.; Ingildsen, P.; Rasmussen, Michael R.

2006-01-01

Aeration tank settling is a control method allowing settling in the process tank during highhydraulic load. The control method is patented. Aeration tank settling has been applied in several wastewater treatment plants using the present design of the process tanks. Some process tank designs...... and outletcausing a disruption of the sludge blanket at the outlet and thereby reducing the retention of sludge in theprocess tank. The model has allowed us to establish a clear picture of the problems arising at the plantduring aeration tank settling. Secondly, several process tank design changes have been...

Electrochemical probing of high-level radioactive waste tanks containing washed sludge and precipitates

International Nuclear Information System (INIS)

Bickford, D.F.; Congdon, J.W.; Oblath, S.B.

1986-12-01

At the US Department of Energy's Savannah River Plant, corrosion of carbon steel storage tanks containing alkaline, high-level radioactive waste is controlled by specification of limits on waste composition and temperature. Processes for the preparation of waste for final disposal will result in waste with low corrosion inhibitor concentrations and, in some cases, high aromatic organic concentrations, neither of which are characteristic of previous operations. Laboratory tests, conducted to determine minimum corrosion inhibitor levels indicated pitting of carbon steel near the waterline for proposed storage conditions. In situ electrochemical measurements of full-scale radioactive process demonstrations have been conducted to assess the validity of laboratory tests. Probes included pH, Eh (potential relative to a standard hydrogen electrode), tank potential, and alloy coupons. In situ results are compared to those of the laboratory tests, with particular regard given to simulated solution composition. Transition metal hydroxide sludge contains strong passivating species for carbon steel. Washed precipitate contains organic species that lower solution pH and tend to reduce passivating films, requiring higher inhibitor concentrations than the 0.01 molar nitrite required for reactor fuel reprocessing wastes. Periodic agitation, to keep the organic phase suspended, or cathodic protection are possible alternatives to higher nitrite inhibitor concentrations

Underground storage tank integrated demonstration: Evaluation of pretreatment options for Hanford tank wastes

International Nuclear Information System (INIS)

Lumetta, G.J.; Wagner, M.J.; Colton, N.G.; Jones, E.O.

1993-06-01

Separation science plays a central role inn the pretreatment and disposal of nuclear wastes. The potential benefits of applying chemical separations in the pretreatment of the radioactive wastes stored at the various US Department of Energy sites cover both economic and environmental incentives. This is especially true at the Hanford Site, where the huge volume (>60 Mgal) of radioactive wastes stored in underground tanks could be partitioned into a very small volume of high-level waste (HLW) and a relatively large volume of low-level waste (LLW). The cost associated with vitrifying and disposing of just the HLW fraction in a geologic repository would be much less than those associated with vitrifying and disposing of all the wastes directly. Futhermore, the quality of the LLW form (e.g., grout) would be improved due to the lower inventory of radionuclides present in the LLW stream. In this report, we present the results of an evaluation of the pretreatment options for sludge taken from two different single-shell tanks at the Hanford Site-Tanks 241-B-110 and 241-U-110 (referred to as B-110 and U-110, respectively). The pretreatment options examined for these wastes included (1) leaching of transuranic (TRU) elements from the sludge, and (2) dissolution of the sludge followed by extraction of TRUs and 90 Sr. In addition, the TRU leaching approach was examined for a third tank waste type, neutralized cladding removal waste

Tank 4 Characterization, Settling, And Washing Studies

International Nuclear Information System (INIS)

Bannochie, C.; Pareizs, J.; Click, D.; Zamecnik, J.

2009-01-01

A sample of PUREX sludge from Tank 4 was characterized, and subsequently combined with a Tank 51 sample (Tank 51-E1) received following Al dissolution, but prior to a supernate decant by the Tank Farm, to perform a settling and washing study to support Sludge Batch 6 preparation. The sludge source for the majority of the Tank 51-E1 sample is Tank 12 HM sludge. The Tank 51-E1 sample was decanted by SRNL prior to use in the settling and washing study. The Tank 4 sample was analyzed for chemical composition including noble metals. The characterization of the Tank 51-E1 sample, used here in combination with the Tank 4 sample, was reported previously. SRNL analyses on Tank 4 were requested by Liquid Waste Engineering (LWE) via Technical Task Request (TTR) HLE-TTR-2009-103. The sample preparation work is governed by Task Technical and Quality Assurance Plan (TTQAP), and analyses were controlled by an Analytical Study Plan and modifications received via customer communications. Additional scope included a request for a settling study of decanted Tank 51-E1 and a blend of decanted Tank 51-E1 and Tank 4, as well as a washing study to look into the fate of undissolved sulfur observed during the Tank 4 characterization. The chemistry of the Tank 4 sample was modeled with OLI Systems, Inc. StreamAnalyzer to determine the likelihood that sulfate could exist in this sample as insoluble Burkeite (2Na 2 SO 4 · Na 2 CO 3 ). The OLI model was also used to predict the composition of the blended tank materials for the washing study. The following conclusions were drawn from the Tank 4 analytical results reported here: (1) Any projected blend of Tank 4 and the current Tank 51 contents will produce a SB6 composition that is lower in Ca and U than the current SB5 composition being processed by DWPF. (2) Unwashed Tank 4 has a relatively large initial S concentration of 3.68 wt% on a total solids basis, and approximately 10% of the total S is present as an insoluble or undissolved form

History of waste tank 12, 1956 through 1974

International Nuclear Information System (INIS)

Davis, T.L.; Tharin, D.W.; Lohr, D.R.

1978-09-01

Tank 12 was placed in service as a receiver for high heat waste (HW) in September 1956 and continued in this service through 1974. From August 1963 through December 1974, the supernate was decanted (leaving the sludge) five times to allow the tank to be refilled with HW. Inspections have been made and photographs taken in the annular space with an optical periscope and a lead-shielded camera. A salt-encrusted leak site was discovered in May 1974. No other leak sites have been found. Analytical samples have been taken of sludge, supernate, and vapor. Primary tank wall thickness, heat transfer coefficient measurements, and profiles of tank temperature differences have been obtained. Several modifications to equipment and various equipment repairs were made

Waste Tank Organic Safety Project organic concentration mechanisms task. FY 1994 progress report

International Nuclear Information System (INIS)

Gerber, M.A.

1994-09-01

The Pacific Northwest Laboratory (PNL), Waste Tank Organic Safety Project is conducting research to support Westinghouse Hanford Company's (WHC) Waste Tank Safety Program, sponsored by the U.S. Department of Energy's Tank Farm Project Office. The goal of PNL's program is to provide a scientific basis for analyzing organics in Hanford's underground storage tanks (USTs) and for determining whether they are at concentrations that pose a potentially unsafe condition. Part of this research is directed toward determining what organic concentrations are safe by conducting research on organic aging mechanisms and waste energetics to assess the conditions necessary to produce an uncontrolled energy release in tanks due to reactions between the organics and the nitrate and nitrate salts in the tank wastes. The objective of the Organic Concentration Mechanisms Task is to assess the degree of localized enrichment of organics to be expected in the USTs due to concentration mechanisms. This report describes the progress of research conducted in FY 1994 on two concentration mechanisms of interest to the tank safety project: (1) permeation of a separate organic liquid phase into the interstitial spaces of the tank solids during the draining of free liquid from the tanks; and (2) concentration of organics on the surfaces of the solids due to adsorption. Three experiments were conducted to investigate permeation of air and solvent into a sludge simulant that is representative of single-shell tank sludge. The permeation behavior of air and solvent into the sludge simulant can be explained by the properties of the fluid pairs (air/supernate and solvent supernate) and the sludge. One important fluid property is the interfacial tension between the supernate and either the solvent or air. In general, the greater the interfacial tension between two fluids, the more difficult it will be for the air or solvent to displace the supernate during dewatering of the sludge

Waste acceptance and waste loading for vitrified Oak Ridge tank waste

International Nuclear Information System (INIS)

Harbour, J.R.; Andrews, M.K.

1997-01-01

The Office of Science and Technology of the DOE has funded a joint project between the Oak Ridge National Laboratory (ORNL) and the Savannah River Technology Center (SRTC) to evaluate vitrification and grouting for the immobilization of sludge from ORNL tank farms. The radioactive waste is from the Gunite and Associated Tanks (GAAT), the Melton Valley Storage Tanks (MVST), the Bethel Valley Evaporator Service Tanks (BVEST), and the Old Hydrofractgure Tanks (OHF). Glass formulation development for sludge from these tanks is discussed in an accompanying article for this conference (Andrews and Workman). The sludges contain transuranic radionuclides at levels which will make the glass waste form (at reasonable waste loadings) TRU. Therefore, one of the objectives for this project was to ensure that the vitrified waste form could be disposed of at the Waste Isolation Pilot Plant (WIPP). In order to accomplish this, the waste form must meet the WIPP Waste Acceptance Criteria (WAC). An alternate pathway is to send the glass waste forms for disposal at the Nevada Test Site (NTS). A sludge waste loading in the feed of 6 wt percent will lead to a waste form which is non-TRU and could potentially be disposed of at NTS. The waste forms would then have to meet the requirements of the NTS WAC. This paper presents SRTC''s efforts at demonstrating that the glass waste form produced as a result of vitrification of ORNL sludge will meet all the criteria of the WIPP WAC or NTS WAC

USE OF AN EQUILIBRIUM MODEL TO FORECAST DISSOLUTION EFFECTIVENESS, SAFETY IMPACTS, AND DOWNSTREAM PROCESSABILITY FROM OXALIC ACID AIDED SLUDGE REMOVAL IN SAVANNAH RIVER SITE HIGH LEVEL WASTE TANKS 1-15

International Nuclear Information System (INIS)

KETUSKY, EDWARD

2005-01-01

This thesis details a graduate research effort written to fulfill the Magister of Technologiae in Chemical Engineering requirements at the University of South Africa. The research evaluates the ability of equilibrium based software to forecast dissolution, evaluate safety impacts, and determine downstream processability changes associated with using oxalic acid solutions to dissolve sludge heels in Savannah River Site High Level Waste (HLW) Tanks 1-15. First, a dissolution model is constructed and validated. Coupled with a model, a material balance determines the fate of hypothetical worst-case sludge in the treatment and neutralization tanks during each chemical adjustment. Although sludge is dissolved, after neutralization more is created within HLW. An energy balance determines overpressurization and overheating to be unlikely. Corrosion induced hydrogen may overwhelm the purge ventilation. Limiting the heel volume treated/acid added and processing the solids through vitrification is preferred and should not significantly increase the number of glass canisters

76 FR 76677 - Hazardous Waste Management System; Identification and Listing of Hazardous Waste; Proposed Exclusion

Science.gov (United States)

2011-12-08

... requested the residual solids from processed storm water tank sludge be excluded from the F037 waste listing... sludge removed from two storm water tanks at its Billings, Montana refinery and processed in accordance... exclusion would be valid only when sludge from the two storm water tanks is dewatered and de-oiled using a...

Effect of colloidal aggregation on the sedimentation and rheological properties of tank waste

International Nuclear Information System (INIS)

Rector, D.R.; Bunker, B.C.

1995-09-01

Tank farm experience and work performed under the Tank Waste Treatment Science task of the Tank Waste Remediation System (TWRS) Pretreatment Technology Development Project indicate that colloidal interactions can have an enormous impact on tank waste processing. This report provides the theoretical and experimental background required to understand how such agglomeration phenomena control the sedimentation and theological behavior of colloidal tank wastes. First, the report describes the conditions under which the colloidal particles present in tank sludge are expected to aggregate. Computational models have been developed to predict solution conditions leading to agglomeration, and to predict the rate and size of aggregate growth. The models show that tank sludge should be heavily agglomerated under most baseline processing conditions. Second, the report describes models used to predict sedimentation rates and equilibrium sediment density profiles based on knowledge of agglomerate structures. The sedimentation models provide a self-consistent picture that explains the apparent discrepancies between bench-top experiments and tank-farm experience. Finally, both discrete and empirical models are presented that can be used to rationalize and predict the rheological properties of colloidal sludge suspensions. In all cases, model predictions are compared and contrasted with experimental results. The net results indicate that most of the observed behaviors of real sludges can be predicted, understood, and perhaps ultimately controlled by understanding a few key central concepts regarding agglomeration phenomena

Effects of alkali types on waste activated sludge (WAS) fermentation and microbial communities.

Science.gov (United States)

Li, Xiaoling; Peng, Yongzhen; Li, Baikun; Wu, Changyong; Zhang, Liang; Zhao, Yaqian

2017-11-01

The effects of two alkali agents, NaOH and Ca(OH) 2 , on enhancing waste activated sludge (WAS) fermentation and short chain fatty acids (SCFAs) accumulation were studied in semi-continuous stirred tank reactors (semi-CSTR) at different sludge retention time (SRT) (2-10 d). The optimum SRT for SCFAs accumulation of NaOH and Ca(OH) 2 adding system was 8 d and 10 d, respectively. Results showed that the average organics yields including soluble chemical oxygen demand (SCOD), protein, and carbohydrate in the NaOH system were as almost twice as that in the Ca(OH) 2 system. For Ca(OH) 2 system, sludge hydrolysis and protein acidification efficiencies were negatively affected by Ca 2+ precipitation, which was revealed by the decrease of Ca 2+ concentration, the rise of zeta potential and better sludge dewaterability in Ca(OH) 2 system. In addition, Firmicutes, Proteobacteria and Actinobacteria were the main microbial functional groups in both types of alkali systems. NaOH system obtained higher microbial quantities which led to better acidification. For application, however, Ca(OH) 2 was more economically feasible owning to its lower price and better dewaterability of residual sludge. Copyright © 2017 Elsevier Ltd. All rights reserved.

Transuranic Waste Processing Center (TWPC) Legacy Tank RH-TRU Sludge Processing and Compliance Strategy - 13255

Energy Technology Data Exchange (ETDEWEB)

Rogers, Ben C.; Heacker, Fred K.; Shannon, Christopher [Wastren Advantage, Inc., Transuranic Waste Processing Center, 100 WIPP Road, Lenoir City, Tennessee 37771 (United States); and others

2013-07-01

The U.S. Department of Energy (DOE) needs to safely and efficiently treat its 'legacy' transuranic (TRU) waste and mixed low-level waste (LLW) from past research and defense activities at the Oak Ridge National Laboratory (ORNL) so that the waste is prepared for safe and secure disposal. The TWPC operates an Environmental Management (EM) waste processing facility on the Oak Ridge Reservation (ORR). The TWPC is classified as a Hazard Category 2, non-reactor nuclear facility. This facility receives, treats, and packages low-level waste and TRU waste stored at various facilities on the ORR for eventual off-site disposal at various DOE sites and commercial facilities. The Remote Handled TRU Waste Sludge held in the Melton Valley Storage Tanks (MVSTs) was produced as a result of the collection, treatment, and storage of liquid radioactive waste originating from the ORNL radiochemical processing and radioisotope production programs. The MVSTs contain most of the associated waste from the Gunite and Associated Tanks (GAAT) in the ORNL's Tank Farms in Bethel Valley and the sludge (SL) and associated waste from the Old Hydro-fracture Facility tanks and other Federal Facility Agreement (FFA) tanks. The SL Processing Facility Build-outs (SL-PFB) Project is integral to the EM cleanup mission at ORNL and is being accelerated by DOE to meet updated regulatory commitments in the Site Treatment Plan. To meet these commitments a Baseline (BL) Change Proposal (BCP) is being submitted to provide continued spending authority as the project re-initiation extends across fiscal year 2012 (FY2012) into fiscal year 2013. Future waste from the ORNL Building 3019 U-233 Disposition project, in the form of U-233 dissolved in nitric acid and water, down-blended with depleted uranyl nitrate solution is also expected to be transferred to the 7856 MVST Annex Facility (formally the Capacity Increase Project (CIP) Tanks) for co-processing with the SL. The SL-PFB project will construct

Transuranic Waste Processing Center (TWPC) Legacy Tank RH-TRU Sludge Processing and Compliance Strategy - 13255

International Nuclear Information System (INIS)

Rogers, Ben C.; Heacker, Fred K.; Shannon, Christopher

2013-01-01

The U.S. Department of Energy (DOE) needs to safely and efficiently treat its 'legacy' transuranic (TRU) waste and mixed low-level waste (LLW) from past research and defense activities at the Oak Ridge National Laboratory (ORNL) so that the waste is prepared for safe and secure disposal. The TWPC operates an Environmental Management (EM) waste processing facility on the Oak Ridge Reservation (ORR). The TWPC is classified as a Hazard Category 2, non-reactor nuclear facility. This facility receives, treats, and packages low-level waste and TRU waste stored at various facilities on the ORR for eventual off-site disposal at various DOE sites and commercial facilities. The Remote Handled TRU Waste Sludge held in the Melton Valley Storage Tanks (MVSTs) was produced as a result of the collection, treatment, and storage of liquid radioactive waste originating from the ORNL radiochemical processing and radioisotope production programs. The MVSTs contain most of the associated waste from the Gunite and Associated Tanks (GAAT) in the ORNL's Tank Farms in Bethel Valley and the sludge (SL) and associated waste from the Old Hydro-fracture Facility tanks and other Federal Facility Agreement (FFA) tanks. The SL Processing Facility Build-outs (SL-PFB) Project is integral to the EM cleanup mission at ORNL and is being accelerated by DOE to meet updated regulatory commitments in the Site Treatment Plan. To meet these commitments a Baseline (BL) Change Proposal (BCP) is being submitted to provide continued spending authority as the project re-initiation extends across fiscal year 2012 (FY2012) into fiscal year 2013. Future waste from the ORNL Building 3019 U-233 Disposition project, in the form of U-233 dissolved in nitric acid and water, down-blended with depleted uranyl nitrate solution is also expected to be transferred to the 7856 MVST Annex Facility (formally the Capacity Increase Project (CIP) Tanks) for co-processing with the SL. The SL-PFB project will construct and install

Improving of Mixing by Submerged Rotary Jet (SRJ) System in a Large Industrial Storage Tank by CFD Techniques

Science.gov (United States)

Barekatain, H.; Hashemabadi, S. H.

2011-09-01

This paper reports the result of a CFD (Computational Fluid Dynamics) study on the Submerged Rotary Jet (SRJ) mixing system in a large industrial crude oil storage tank (one million barrels). This system has been installed on the tank just for reduction of sludge, but improper installation causes more accumulation of sludge on one side of tank. The main question is: How can we improve the mixing operation in this tank? For the purpose, a three dimensional modeling is carried out using an in-house CFD code and RNG k-ɛ model for turbulence prediction. The results show that pump suction location and crude oil velocity in tank are most effective factors on the sludge amount. Then, different ways such as increasing of jet flow rate, increasing and decreasing of tank height and reducing of nozzle diameter have been investigated. Finally, in this case, the results show the sedimentation of sludge in whole tank can be removed by 20% increasing of jet flow rate.

Conversion of agricultural waste, sludges and pulp residues into nanofibers for innovative polymer composites

OpenAIRE

Samyn, Pieter; Carleer, Robert

2017-01-01

Agricultural waste fractions from seasonal crops (corn stover, bagasse, flax), sludges and paper pulp residues contain an important source of lignocellulosic materials that can be recovered and used as material fractions instead of being burnt for energy recovery. Due to the heterogeneity of named products, however, novel processing routes should be developed for the recovery of the lignocellulosic materials at nanoscale. Therefore, we will use nanotechnological routes to transform the res...

Pentachlorophenol (PCP) sludge recycling unit

International Nuclear Information System (INIS)

1994-08-01

The Guelph Utility Pole Company treats utility poles by immersion in pentachlorophenol (PCP) or by pressure treatment with chromated copper arsenate (CCA). The PCP treatment process involves a number of steps, each producing a certain amount of sludge and other wastes. In a plant upgrading program to improve processing and treatment of poles and to reduce and recycle waste, a PCP recovery unit was developed, first as an experimental pilot-scale unit and then as a full-scale unit. The PCP recovery unit is modular in design and can be modified to suit different requirements. In a recycling operation, the sludge is pumped through a preheat system (preheated by waste heat) and suspended solids are removed by a strainer. The sludge is then heated in a tank and at a predetermined temperature it begins to separate into its component parts: oil, steam, and solids. The steam condenses to water containing low amounts of light oil, and this water is pumped through an oil/water separator. The recovered oil is reused in the wood treatment process and the water is used in the CCA plant. The oil remaining in the tank is reused in PCP treatment and the solid waste, which includes small stones and wood particles, is removed and stored. By the third quarter of operation, the recovery unit was operating as designed, processing ca 10,000 gal of sludge. This sludge yielded 6,500 gal of water, 3,500 gal of oil, and ca 30 gal of solids. Introduction of the PCP sludge recycling system has eliminated long-term storage of PCP sludge and minimized costs of hazardous waste disposal. 4 figs

HANFORD TANK CLEANUP UPDATE MAY 2009

International Nuclear Information System (INIS)

Holloway, J.N.

2009-01-01

Retrieval of waste from single-shell tank C-110 resumed in January making it the first waste retrieval operation for WRPS since taking over Hanford's Tank Operations Contract last October. Now, with approximately 90 percent of the waste removed, WRPS believes that modified sluicing has reached the limits of the technology to remove any further waste and is preparing documentation for use in decision making about any future retrieval actions. Tank C-110 is located in C Fann near the center of the Hanford Site. It is a 530,000 gallon tank, built in 1946, and held approximately 126,000 gallons of sludge and other radioactive and chemical waste materials when retrieval resumed. Modified sluicing technology uses liquid waste from a nearby double-shell tank to break up, dissolve and mobilize the solid material so it can be pumped. Because of the variety of waste fon11S, sluicing is often not able to remove all of the waste. The remaining waste will next be sampled for analysis, and results will be used to guide decisions regarding future actions. Work is moving rapidly in preparation to retrieve waste from a second single-shell tank this summer and transfer it to safer double-shell tank storage. Construction activities necessary to retrieve waste from Tank C-104, a 530,000 gallon tank built in 1943, are approximately 60 percent complete as WRPS maintains its focus on reducing the risk posed by Hanford's aging single-shell waste tanks. C-104 is one of Hanford's oldest radioactive and chemical waste storage tanks, containing approximately 263,000 gallons of wet sludge with a top layer that is dry and powdery. This will be the largest sludge volume retrieval ever attempted using modified sluicing technology. Modified sluicing uses high pressure water or liquid radioactive waste sprayed from nozzles above the waste. The liquid dissolves and/or mobilizes the waste so it can be pumped. In addition to other challenges, tank C-104 contains a significant amount of plutonium and

Oxalate Mass Balance During Chemical Cleaning in Tank 5F

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.; Fink, S.

2011-07-08

The Savannah River Site (SRS) is preparing Tank 5F for closure. The first step in preparing the tank for closure is mechanical sludge removal. Following mechanical sludge removal, SRS performed chemical cleaning with oxalic acid to remove the sludge heel. Personnel are currently assessing the effectiveness of the chemical cleaning to determine whether the tank is ready for closure. SRS personnel collected liquid samples during chemical cleaning and submitted them to Savannah River National Laboratory (SRNL) for analysis. Following chemical cleaning, they collected a solid sample (also known as 'process sample') and submitted it to SRNL for analysis. The authors analyzed these samples to assess the effectiveness of the chemical cleaning process. Analysis of the anions showed the measured oxalate removed from Tank 5F to be approximately 50% of the amount added in the oxalic acid. To close the oxalate mass balance, the author collected solid samples, leached them with nitric acid, and measured the concentration of cations and anions in the leachate.

Nitrogen mineralisation and greenhouse gas emission from the soil application of sludge from reed bed mineralisation systems

DEFF Research Database (Denmark)

Gómez-Muñoz, B; Larsen, Julie Dam; Bekiaris, G

2017-01-01

A sludge treatment reed bed system (STRB) is a technology used for dewatering and stabilising sewage sludge via assisted biological mineralisation, which creates a sludge residue suitable for use as fertiliser on agricultural land. We evaluated the effect of sludge residue storage time (stabilisa......A sludge treatment reed bed system (STRB) is a technology used for dewatering and stabilising sewage sludge via assisted biological mineralisation, which creates a sludge residue suitable for use as fertiliser on agricultural land. We evaluated the effect of sludge residue storage time...... (stabilisation time) for three STRBs on soil N mineralisation and CO2 and N2O emissions in soil. The experiment revealed that the N mineralisation rate and emissions of CO2 and N2O decreased as a function of treatment time in the STRBs. Mixed sludge residue (sludge residue subjected to different treatment times......) for the three STRBs resulted in N mineralisation rates similar to the sludge residue subjected to a shorter treatment time but lower N2O emissions similar to the values of the older sludge residue. This finding reveals that combining fresh and more stabilised sludge residue ensures high N availability...

Feasibility Study on Using Two Mixer Pumps for Tank 241-AY-102 Waste Mixing

International Nuclear Information System (INIS)

Onishi, Yasuo; Wells, Beric E.

2004-01-01

The current waste retrieval plan at Hanford calls for using two mixer pumps to mix the waste stored in double-shell Tank 214-AY-102. The objective of this evaluation was to determine whether two rotating 300-hp mixer pumps placed 22 ft (6.7 m) off-center in the tank could adequately mix the AY-102 waste. The tank currently contains high-level waste that is 248 inches (6.3 m) deep, comprising 62 inches (1.58 m) of sludge and 186 inches (4.72 m) of supernatant liquid (Galbraith and others 2002). Based on the available data, AY-102 waste properties were determined, including the densities of liquid and agglomerated settled solids and crystals, the volume fraction of settled solids, the solid particle size distribution, the liquid and slurry viscosities, and the yield stress in shear (shear strength) of the settled solids layer. To evaluate the likely and bounding cases of AY-102 waste mixing, sludge erosion modeling was performed with a median value of 1,090 Pa (likely condition) and a conservative (more difficult to erode) 97.5 percentile value of 2,230 Pa for shear strength. According to model predictions, the two rotating mixer pumps would erode 89% of the sludge with shear strength of 1,090 Pa. They would erode sludge up to 41 ft (12.5 m) away from the mixer pumps but would not mobilize the bottom 2.5 inches (0.06-m) of sludge or sludge in the areas next to the tank wall, more than 26 ft (7.9 m) away. Once the sludge is mobilized, the solids were predicted to be uniformly suspended within the tank within a 1-vol% concentration variation except those in few inches at the bottom. With shear strength of 2,230 Pa, the two pumps would erode 85% of the sludge, slightly less than the 1,090-Pa shear strength case. In this case, the pump jets would mobilize the sludge up to 38 ft (11.6 m), except the bottom 2.5 inches of sludge. The mixer pumps would also leave the sludge at the tank wall, which is 20 ft or more from the pumps. Similar to the 1,090 Pa case, the solids were

Anammox biofilm in activated sludge swine wastewater treatment plants.

Science.gov (United States)

Suto, Ryu; Ishimoto, Chikako; Chikyu, Mikio; Aihara, Yoshito; Matsumoto, Toshimi; Uenishi, Hirohide; Yasuda, Tomoko; Fukumoto, Yasuyuki; Waki, Miyoko

2017-01-01

We investigated anammox with a focus on biofilm in 10 wastewater treatment plants (WWTPs) that use activated sludge treatment of swine wastewater. In three plants, we found red biofilms in aeration tanks or final sedimentation tanks. The biofilm had higher anammox 16S rRNA gene copy numbers (up to 1.35 × 10 12 copies/g-VSS) and higher anammox activity (up to 295 μmoL/g-ignition loss/h) than suspended solids in the same tank. Pyrosequencing analysis revealed that Planctomycetes accounted for up to 17.7% of total reads in the biofilm. Most of them were related to Candidatus Brocadia or Ca. Jettenia. The highest copy number and the highest proportion of Planctomycetes were comparable to those of enriched anammox sludge. Thus, swine WWTPs that use activated sludge treatment can fortuitously acquire anammox biofilm. Thus, concentrated anammox can be detected by focusing on red biofilm. Copyright © 2016 Elsevier Ltd. All rights reserved.

Oak Ridge National Laboratory Melton Valley Storage Tanks Waste filtration process evaluation

International Nuclear Information System (INIS)

Walker, B.W.; McCabe, D.J.

1997-01-01

The purpose of this filter study was to evaluate cross-flow filtration as effective solid-liquid separation technology for treating Oak Ridge National Laboratory wastes, outline operating conditions for equipment, examine the expected filter flow rates, and determine proper cleaning.The Gunite Tanks at the Oak Ridge National Laboratory contain heels which are a mixture of sludge, wash water, and bentonite clay. The tanks are to be cleaned out with a variety of flushing techniques and the dilute mixture transferred to another storage tank. One proposal is to transfer this mixture into existing Melton Valley Storage Tanks (MVST), which already contain a large amount of sludge and supernate. The mixed aqueous phase will then be transferred to new MVST, which are prohibited from containing insoluble solids. To separate the solid from the liquid and thereby prevent solids transfer into the new MVST, a technique is needed that can cleanly separate the sludge and bentonite clay from the supernate. One proposed method for solid liquid separation is cross-flow filtration. Cross-flow filtration has been used at the Savannah River and West Valley sites for treatment of tank waste, and is being tested for applicability at other sites. The performance of cross-flow filters with sludge has been tested, but the impact of sludge combined with bentonite clay has not. The objective of this test was to evaluate the feasibility of using cross-flow filters to perform the solid liquid separation required for the mixture of Gunite and MVST tank wastes

Underground tank remediation by use of in situ vitrification

International Nuclear Information System (INIS)

Thompson, L.E.

1991-02-01

Pacific Northwest Laboratory (PNL) is developing a remedial action technology for underground storage tanks through the adaptation of the in situ vitrification (ISV) process. The ISV process is a thermal treatment processes that was originally developed for the stabilization of contaminated soil contaminated with transuranic waste at the Hanford Site in southeastern Washington for the Department of Energy (DOE). The application of ISV to underground storage tanks represents an entirely new application of the ISV technology and is being performed in support of the DOE primarily for the Hanford site and the Oak Ridge National Laboratory (ORNL). A field scale test was conducted in September 1990 at Hanford on a small cement and stainless steel tank (1-m dia.) that contained a simulated refractory sludge representing a worst-case sludge composition. The tank design and sludge composition was based on conditions present at the ORNL. The sludge contained high concentrations of heavy metals including lead, mercury, and cadmium, and also contained high levels of stable cesium and strontium to represent the predominant radionuclide species present in the tank wastes. The test was highly successful in that the entire tank and surrounding soil was transformed into a highly leach resistant glass and crystalline block with a mass of approximately 30 tons. During the process, the metal shell of the tank forms a metal pool at the base of the molten soil. Upon cooling, the glass and metal phases were subjected to TCLP (toxic characteristic leach procedure) testing and passed the TCLP criteria. Additional sampling and analyses are ongoing to determine the bulk composition of the waste forms, the fraction of volatile or semi-volatile species released to the off-gas treatment system, and to determine whether any soil surrounding the monolith was contaminated as a result of the ISV process. 4 refs., 5 figs., 3 tabs

Characterization Of The As-Received Sludge Batch 9 Qualification Sample (Htf-51-15-81)

Energy Technology Data Exchange (ETDEWEB)

Pareizs, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-09-30

Savannah River National Laboratory (SRNL) personnel have been requested to qualify the next sludge batch (Sludge Batch 9 – SB9) for processing at the Defense Waste Processing Facility (DWPF). To accomplish this task, Savannah River Remediation (SRR) has sent SRNL a 3-L slurried sample of Tank 51H (HTF-51-15-81) to be characterized, washed, and then used in a lab-scale demonstration of the DWPF flowsheet (potentially after combining with Tank 40H sludge). This report documents the first steps of the qualification process – characterization of the as-received Tank 51H qualification sample. These results will be used to support a reprojection of SB9 by SRR from which final Tank 51H washing, frit development, and Chemical Processing Cell (CPC) activities will be based.

History of waste tank 9 , 1955--1974

International Nuclear Information System (INIS)

Tharin, D.W.; Lohr, D.R.

1979-01-01

Tank 9 was placed in service as a receiver for Purex HLW on July 19, 1955. Filling was essentially completed in December 1955, and this original complement of waste remained in the tank until December 1965, when most of the liquid was decanted to allow refilling. In July 1966, the remaining liquid and approximately 15 inches of sludge were removed using 3000 to 3500 psi water introduced through nozzles to mobilize the sludge. The tank was then used as a receiver and cooler for aged HLW solution concentrated by the tank farm evaporator; the resulting crystallized salt, covered with saturated solution, is now stored in this tank. Inspections have been made of the tank interior and annulus by direct observation and with a 40-ft optical periscope. Analytical samples have been taken of the sludge, supernate, vapor, and leaked material in the annulus. Top-to-bottom profiles of radiation and temperature have been obtained in the annulus and tank, respectively, and measurements have been made of roof deflection caused by salt adhering to roof-supported cooling coils. Leaked waste was discovered in the annulus pan in October 1957. During 1958-59, the annulus pan was flushed nine times with water in 2000-gallon batches, jetting the waste and flush water into the primary tank. However, waste leakage into the annulus continued. The maximum liquid depth reached in the annulus was about 12 inches. This was jetted out in 1961., but some leakage continued theeeafter as indicated by roddings. The roddings showed no standing liquid by August 1964, but some liquid may have been present undera salt crust. In March 1972, salt depth in the annulus was measured to be 8 to 10 in., and the bottom 3 in. was quite wet. The salt remains although most of the liquid has been removed

Cross flow filtration of aqueous radioactive tank wastes

International Nuclear Information System (INIS)

McCabe, D.J.; Reynolds, B.A.; Todd, T.A.; Wilson, J.H.

1997-01-01

The Tank Focus Area (TFA) of the Department of Energy (DOE) Office of Science and Technology addresses remediation of radioactive waste currently stored in underground tanks. Baseline technologies for treatment of tank waste can be categorized into three types of solid liquid separation: (a) removal of radioactive species that have been absorbed or precipitated, (b) pretreatment, and (c) volume reduction of sludge and wash water. Solids formed from precipitation or absorption of radioactive ions require separation from the liquid phase to permit treatment of the liquid as Low Level Waste. This basic process is used for decontamination of tank waste at the Savannah River Site (SRS). Ion exchange of radioactive ions has been proposed for other tank wastes, requiring removal of insoluble solids to prevent bed fouling and downstream contamination. Additionally, volume reduction of washed sludge solids would reduce the tank space required for interim storage of High Level Wastes. The scope of this multi-site task is to evaluate the solid/liquid separations needed to permit treatment of tank wastes to accomplish these goals. Testing has emphasized cross now filtration with metal filters to pretreat tank wastes, due to tolerance of radiation and caustic

Sample preparation of tank 241-C-106 grab samples and testing For compatibility with tank 241-AY-102 supernate

International Nuclear Information System (INIS)

Crawford, B.A.

1996-01-01

This test plan describes a sample separation method which will be used to obtain physical measurements and separated 241-C-106 solids and supernate fractions. In addition compatibility of tank 241-C-106 sludge with tank 241-AY-102 supernate will be determined

Determination of the Removal Efficiency of Linear Alkyl Benzene Sulphonate Acids (LAS in Fixed Bed Aeration Tank and Conventional Activated Sludge

Directory of Open Access Journals (Sweden)

Asghar Ebrahimi

2011-03-01

Full Text Available Linear Alkyl Benzene Sulphonate Acids (LAS are one of the anionic surfactants that are produced and used in large quantities in different countries and find their way into the natural environment through sewer systems. These compounds may potentially cause environmental hazards in such surface waters as rivers. It is, therefore, necessary to remove as much of these compounds as possible by biological processes in wastewater treatment plants. For this purpose, four parallel biological reactors were constructed that used the conventional activated sludge and aeration tanks with fixed bed on the bench scale in order to evaluate the removal efficiency of LAS. The reactors were operated under conditions similar to domestic wastewater treatment plants. Parameters of interest were measured according to standard methods and ANOVA and T-test were used for the statistical analysis of the data. The results showed that aeration tanks with fixed beds yielded higher values of LAS and COD removal and air consumption compared to the conventional activated sludge system. It was shown that the two systems studied achieved LAS removal efficiencies of 96% and 94% for an influent LAS concentration of 5 mg/L. Further, it was found that the effluents from both systems satisfied water quality standards for discharge into surface waters (

Criteria: waste tank isolation and stabilization

Energy Technology Data Exchange (ETDEWEB)

Metz, W.P.; Ogren, W.E.

1976-09-01

The crystallized Hanford high-level wastes stored in single-shell underground tanks consist of sludges and salt cakes covered with supernatural liquor. Purpose of stabilization and isolation is to reduce the releases and losses as a result of a loss of tank integrity. The tanks will be modified so that no inadvertent liquid additions can be made. Criteria for the isolation and stabilization are given and discussed briefly. (DLC)

Criteria: waste tank isolation and stabilization

International Nuclear Information System (INIS)

Metz, W.P.; Ogren, W.E.

1976-09-01

The crystallized Hanford high-level wastes stored in single-shell underground tanks consist of sludges and salt cakes covered with supernatural liquor. Purpose of stabilization and isolation is to reduce the releases and losses as a result of a loss of tank integrity. The tanks will be modified so that no inadvertent liquid additions can be made. Criteria for the isolation and stabilization are given and discussed briefly

K Basin sludge dissolution engineering study

International Nuclear Information System (INIS)

Westra, A.G.

1998-01-01

The purpose of this engineering study is to investigate the available technology related to dissolution of the K Basin sludge in nitric acid. The conclusion of this study along with laboratory and hot cell tests with actual sludge samples will provide the basis for beginning conceptual design of the sludge dissolver. The K Basin sludge contains uranium oxides, fragments of metallic U, and some U hydride as well as ferric oxyhydroxide, aluminum oxides and hydroxides, windblown sand that infiltrated the basin enclosure, ion exchange resin, and miscellaneous materials. The decision has been made to dispose of this sludge separate from the fuel elements stored in the basins. The sludge will be conditioned so that it meets Tank Waste Remediation System waste acceptance criteria and can be sent to one of the underground storage tanks. Sludge conditioning will be done by dissolving the fuel constituents in nitric acid, separating the insoluble material, adding neutron absorbers for criticality safety, and then reacting the solution with caustic to co-precipitate the uranium and plutonium. There will be five distinct feed streams to the sludge conditioning process two from the K East (KE) Basin and three from the K West (KW) Basin. The composition of the floor and pit sludges which contain more iron oxides and sand than uranium is much different than the canister sludges which are composed of mostly uranium oxides. The sludge conditioning equipment will be designed to process all of the sludge streams, but some of the operating parameters will be adjusted as necessary to handle the different sludge stream compositions. The volume of chemical additions and the amount of undissolved solids will be much different for floor and pit sludge than for canister sludge. Dissolution of uranium metal and uranium dioxide has been studied quite thoroughly and much information is available. Both uranium metal and uranium dioxide have been dissolved on a large scale in nuclear fuel

History of waste tank 1, 1954 through 1974

International Nuclear Information System (INIS)

McNatt, F.G.; Stevens, W.E.

1978-10-01

Tank 1 was placed in service as a receiver of high heat waste (HW) in October 1954. The supernate was removed from the tank in October 1961 and the tank began receiving low heat waste (LW) in January 1962. The LW supernate was decanted in October 1962 and prior to beginning a second HW filling in April 1963. The supernate from this HW filling was decanted twice in 1969. Sludge removal operations were conducted in May and August 1969 in order to use tank 1 for salt storage. The first evaporator concentrate receipt was in September 1969 and tank 1 has only been used as a salt storage tank since. Leakage from the tank into the annulus was discovered in February 1969. Deposits less than 1/4 inch deep of leaked waste were found on the pan floor. However, no leak sites have been found. Inspections of the tank interior and annulus were made by direct observation and by using a 40-ft optical periscope. Samples of sludge, supernate, tank vapors, and leaked material into the annulus were analyzed and tank temperature profiles were taken. Deflection measurements were made of the primary tank bottom knuckle plate while filling the tank with salt. Two vertical cooling coils have failed. Several equipment modifications and various equipment repairs were made. 18 figures, 2 tables

Safety evaluation of the ESP sludge washing baselines runs. Revision 2

International Nuclear Information System (INIS)

Gupta, M.K.

1993-01-01

Purpose is to provide the technical basis for evaluation of unreviewed safety question for the Extended Sludge Processing (ESP) Sludge Washing Baseline Runs, which are necessary to resolve technical questions associated with process control (sludge suspension, sludge settling, heat transfer, temperature control). The sludge is currently stored in below-ground tanks and will be prepared for processing at the Defense Waste Processing Facility as part of the Integrated Waste Removal Program for Savannah River Site

K basins sludge removal sludge pretreatment system

International Nuclear Information System (INIS)

Chang, H.L.

1997-01-01

The Spent Nuclear Fuels Program is in the process of planning activities to remove spent nuclear fuel and other materials from the 100-K Basins as a remediation effort for clean closure. The 105 K- East and K-West Basins store spent fuel, sludge, and debris. Sludge has accumulated in the 1 00 K Basins as a result of fuel oxidation and a slight amount of general debris being deposited, by settling, in the basin water. The ultimate intent in removing the sludge and fuel is to eliminate the environmental risk posed by storing fuel at the K Basins. The task for this project is to disposition specific constituents of sludge (metallic fuel) to produce a product stream through a pretreatment process that will meet the requirements, including a final particle size acceptable to the Tank Waste Remediation System (TWRS). The purpose of this task is to develop a preconceptual design package for the K Basin sludge pretreatment system. The process equipment/system is at a preconceptual stage, as shown in sketch ES-SNF-01 , while a more refined process system and material/energy balances are ongoing (all sketches are shown in Appendix C). Thus, the overall process and 0535 associated equipment have been conservatively selected and sized, respectively, to establish the cost basis and equipment layout as shown in sketches ES- SNF-02 through 08

Cleanout of waste storage tanks at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Weeren, H.O.; Lasher, L.C.; McDaniel, E.W.

1984-01-01

In 1943, six storage tanks were built at the Clinton Laboratories [later to become Oak Ridge National Laboratory (ORNL)] to contain wastes generated by wartime research and development operations. During the following years, these tanks became an integral part of the ORNL waste system and accumulated approx. 1.5 x 10 6 L (400,000 gal) of sludge containing radioactive wastes. Recently, over a period of approx. 18 months, these tanks were sluiced, the radioactive sludge resuspended, and the resuspended slurry pumped to the ORNL Hydrofracture Facility for underground disposal. In this paper, a summary of the development work is given, and the process design and constraints are described. The operating difficulties encountered and overcome included grinder blade erosion, malfunctioning instruments, pump suction plugging, and slurry settling. About 90% of the settled sludge (containing approx. 715,000 Ci) was removed from the system

Anaerobic treatment of sludge: focusing on reduction of LAS concentration in sludge

DEFF Research Database (Denmark)

Haagensen, Frank; Mogensen, Anders Skibsted; Angelidaki, Irini

2002-01-01

Anaerobic degradation of linear alkylbenzene sulfonates (LAS) was tested in continuous stirred tank reactors (CSTR). LAS12 was used as a model compound and was spiked on sewage sludge. The experiments clearly showed that transformation of LAS12 occurred under anaerobic conditions. The degree...

Nuclear reactor equipped with a flooding tank and a residual heat removal and emergency cooling system

International Nuclear Information System (INIS)

Schabert, H.P.; Winkler, F.

1975-01-01

A description is given of a nuclear reactor such as a pressurized-water reactor or the like which is equipped with a flooding tank and a residual heat removal and emergency cooling system. The flooding tank is arranged within the containment shell at an elevation above the upper edge of the reactor core and contains a liquid for flooding the reactor core in the event of a loss of coolant

Ferrocyanide safety program: An assessment of the possibility of ferrocyanide sludge dryout

International Nuclear Information System (INIS)

Epstein, M.; Fauske, H.K.; Dickinson, D.R.; Crippen, M.D.; McCormack, J.D.; Cash, R.J.; Meacham, J.E.; Simmons, C.S.

1994-09-01

Much attention has been focused on the Hanford Site radioactive waste storage tanks as a results of problems that have been envisioned for them. One problem is the potential chemical reaction between ferrocyanide precipitate particles and nitrates in the absence of water. This report addresses the question of whether dryout of a portion of ferrocyanide sludge would render it potentially reactive. Various sludge dryout mechanisms were examined to determine if any of them could occur. The mechanisms are: (1) bulk heating of the entire sludge inventory to its boiling point; (2) loss of liquid to the atmosphere via sludge surface evaporation; (3) local drying by boiling in a hot spot region; (4) sludge drainage through a leak in the tank wall; and (5) local drying by evaporation from a warm segment of surface sludge. From the simple analyses presented in this report and more detailed published analyses, it is evident that global loss of water from bulk heating of the sludge to its boiling point or from surface evaporation and vapor transport to the outside air is not credible. Also, from the analyses presented in this report and experimental and analytical work presented elsewhere, it is evident that formation of a dry local or global region of sludge as a result of tank leakage (draining of interstitial liquid) is not possible. Finally, and most importantly, it is concluded that formation of dry local regions in the ferrocyanide sludge by local hot spots or warm surface regions is not possible. The conclusion that local or global dryout is incredible is consistent with four decades of waste storage history, during which sludge temperature have gradually decreased or remained constant and the sludge moisture content has been retained. 54 refs

Sludge Stabilization Campaign blend plan

International Nuclear Information System (INIS)

De Vries, M.L.

1994-01-01

This sludge stabilization blend plan documents the material to be processed and the order of processing for the FY95 Sludge Stabilization Campaign. The primary mission of this process is to reduce the inventory of unstable plutonium bearing sludge. The source of the sludge is residual and glovebox floor sweepings from the production of material at the Plutonium Finishing Plant (PFP). The reactive sludge is currently being stored in various gloveboxes at PFP. There are two types of the plutonium bearing material that will be thermally stabilized in the muffle furnace: Plutonium Reclamation Facility (PRF) sludge and Remote Mechanical C (RMC) Line material

Study of some applications of residual sludges in agriculture using 15N, 32P, 65Zn, 109Cd and 203Hg

International Nuclear Information System (INIS)

Fardeau, J.C.; Guiraud, G.

1979-01-01

Application of residual sludges increases dry matter production. This effect is due to the low C/N of these matters. The possible risks depend on the alteration of ions mobility as PO 4 ---, Zn ++ , Hg ++ and Cd ++ , which are often very strongly absorbed by soil particules. For these investigations, use of radioactive tracers is necessary. We have shown, with 65 Zn ++ , that zinc of sludges is not available for ray-grass and, with 32 PO 4 , that phosphorus mobility declines with lime-treated sludges. The use of isotopic dilution kinetics allows to shown that Hg ++ and Cd ++ are not absorbed in too acidic soils [fr

Tank 241-AZ-101 tank characterization plan

International Nuclear Information System (INIS)

Schreiber, R.D.

1995-01-01

The Defense Nuclear Facilities Safety Board has advised the DOE to concentrate the near-term sampling and analysis activities on identification and resolution of safety issues. The Data Quality Objective (DQO) process was chosen as a tool to be used in the resolution of safety issues. As a result, A revision in the Federal Facilities Agreement and Consent Order (Tri-Party Agreement) milestone M-44 has been made, which states that ''A Tank Characterization Plan (TCP) will also be developed for each double-shell tank (DST) and single-shell tank (SST) using the DQO process. Development of TCPs by the DQO process is intended to allow users to ensure their needs will be met and that resources are devoted to gaining only necessary information''. This document satisfies that requirement for Tank 241-AZ-101 (AZ-101) sampling activities. Tank AZ-101 is currently a non-Watch List tank, so the only DQOs applicable to this tank are the safety screening DQO and the compatibility DQO, as described below. The contents of Tank AZ-101, as of October 31, 1994, consisted of 3,630 kL (960 kgal) of dilute non-complexed waste and aging waste from PUREX (NCAW, neutralized current acid waste). Tank AZ-101 is expected to have two primary layers. The bottom layer is composed of 132 kL of sludge, and the top layer is composed of 3,500 kL of supernatant, with a total tank waste depth of approximately 8.87 meters

The effect of sludge water treatment plant residuals on the properties of compressed brick

Science.gov (United States)

Shamsudin, Shamrul-Mar; Shahidan, S.; Azmi, M. A. M.; Ghaffar, S. A.; Ghani, M. B. Abdul; Saiful Bahari, N. A. A.; Zuki, S. S. M.

2017-11-01

The focus of this study is on the production of compressed bricks which contains sludge water treatment plant (SWTP) residuals obtained from SAJ. The main objective of this study is to utilise and incorporate discarded material (SWTP) in the form of residual solution to produce compressed bricks. This serves as one of the recycling efforts to conserve the environment. This study determined the optimum mix based on a mix ratio of 1:2:4 (cement: sand: soil) in the production of compressed bricks where 5 different mixes were investigated i. e. 0%, 5%, 10%, 20%, and 30% of water treatment plant residue solution. The production of the compressed bricks is in accordance with the Malaysian Standard MS 7.6: 1972 and British Standard BS 3921: 1985 - Compressive Strength & Water Absorption. After being moulded and air dried, the cured bricks were subjected to compression tests and water absorption tests. Based on the tests conducted, it was found that 20% of water treatment plant residue solution which is equivalent to 50% of soil content replacement with a mix composition of [10: cement] [20: sand] [20: soil] [20: water treatment plant residue solution] is the optimum mix. It was also observed that the bricks containing SWTP residuals were lighter in weight compared to the control specimens

Sludge technology assessment

International Nuclear Information System (INIS)

Krause, T.R.; Cunnane, J.C.; Helt, J.E.

1994-12-01

The retrieval, processing, and generation of final waste forms from radioactive tank waste sludges present some of the most challenging technical problems confronting scientists and engineers responsible for the waste management programs at the various Department of Energy laboratories and production facilities. Currently, the Department of Energy is developing a strategy to retrieve, process, and generate a final waste form for the sludge that meets the acceptance criteria for the final disposition. An integral part of this strategy will be use of separation processes that treat the sludge; the goal is to meet feed criteria for the various processes that will generate the final waste form, such as vitrification or grouting. This document is intended to (1) identify separation technologies which are being considered for sludge treatment at various DOE sites, (2) define the current state of sludge treatment technology, (3) identify what research and development is required, (4) identify current research programs within either DOE or academia developing sludge treatment technology, and (5) identify commercial separation technologies which may be applicable. Due to the limited scope of this document, technical evaluations regarding the need for a particular separations technology, the current state of development, or the research required for implementation, are not provided

Experimental study on combustion and slagging characteristics of tannery sludge

International Nuclear Information System (INIS)

Li, Chunyu; Jiang, Xuguang; Fei, Zhenwei; Chi, Yong; Yan, Jianhua

2010-01-01

Incineration is the most reasonable technique for tannery sludge disposal. The combustion and gaseous products emission characteristics of tannery sludge were investigated in this study. Tendency of slagging for combustion residue was also investigated based on the composition and microscopic scanning analysis. The high content of volatile matters and ash in tannery sludge was discovered. It was shown that the thermal decomposition and combustion of tannery sludge mainly occurs in a temperature frame between 150 degree Celsius and 780 degree Celsius. Organic acid was determined as the most important gaseous pollutant at low temperature combustion. The combustion residue from a specially designed furnace was analyzed by X-ray diffractometer (XRD) and energy dispersion spectroscopy (EDS) microprobe coupled in a scanning electron micro-scope (SEM). There is large amount of Ca in the combustion residue, and CaO was the main inorganic composition in these residues. The tannery sludge studied in this paper has a strong tendency of slagging, and the fusion of the residue began at 900 degree Celsius in combustion. It was further discovered that almost all the zinc (Zn) in tannery sludge is volatilized at 900 degree Celsius. The degree of volatilization for heavy metals at 900 degree Celsius followed the order of Zn > Cd >Cu > Mn > Pb > Cr. Most of Cr in tannery sludge is enriched in the residue during combustion. The present study reveals that it is critical to control the combustion temperature for optimal combustion efficiency and minimization of pollutants emission. (author)

Effects of palm oil mill effluent (POME) anaerobic sludge from 500 m ...

African Journals Online (AJOL)

In this study, co-composting of pressed-shredded empty fruit bunches (EFB) and palm oil mill effluent (POME) anaerobic sludge from 500 m3 closed anaerobic methane digested tank was carried out. High nitrogen and nutrients content were observed in the POME anaerobic sludge. The sludge was subjected to the ...

Verification Of The Defense Waste Processing Facility's (DWPF) Process Digestion Methods For The Sludge Batch 8 Qualification Sample

International Nuclear Information System (INIS)

Click, D. R.; Edwards, T. B.; Wiedenman, B. J.; Brown, L. W.

2013-01-01

This report contains the results and comparison of data generated from inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis of Aqua Regia (AR), Sodium Peroxide/Sodium Hydroxide Fusion Dissolution (PF) and Cold Chem (CC) method digestions and Cold Vapor Atomic Absorption analysis of Hg digestions from the DWPF Hg digestion method of Sludge Batch 8 (SB8) Sludge Receipt and Adjustment Tank (SRAT) Receipt and SB8 SRAT Product samples. The SB8 SRAT Receipt and SB8 SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constitutes the SB8 Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 7b (SB7b), to form the SB8 Blend composition

EVALUATION OF MIXING IN THE SLURRY MIX EVAPORATOR AND MELTER FEED TANK

International Nuclear Information System (INIS)

MARINIK, ANDREW

2004-01-01

The Defense Waste Processing Facility (DWPF) vitrifies High Level radioactive Waste (HLW) currently stored in underground tanks at the Savannah River Site (SRS). The HLW currently being processed is a waste sludge composed primarily of metal hydroxides and oxides in caustic slurry. These slurries are typically characterized as Bingham Plastic fluids. The HLW undergoes a pretreatment process in the Chemical Process Cell (CPC) at DWPF. The processed HLW sludge is then transferred to the Sludge Receipt and Adjustment Tank (SRAT) where it is acidified with nitric and formic acid then evaporated to concentrate the solids. Reflux boiling is used to strip mercury from the waste and then the waste is transferred to the Slurry Mix Evaporator tank (SME). Glass formers are added as a frit slurry to the SME to prepare the waste for vitrification. This mixture is evaporated in the SME to the final concentration target. The frit slurry mixture is then transferred to the Melter Feed Tank (MFT) to be fed to the melter

Mixing Envelope D Sludge with LAW Intermediate Products with and without Glass Formers

Energy Technology Data Exchange (ETDEWEB)

Hansen, E.K.

2001-09-21

The Department of Energy (DOE) Office of River Protection is in the process of designing a waste treatment system to process the Hanford Reservation High Level Waste (HLW). Envelope D sludge slurries will be blended with the concentrated Cs/Ts eluates, and the Sr/TRU intermediates separated from Envelope A, B, and C feeds. This study produced two washed simulated sludges (representing tanks 241-AZ-101 and 241-AZ-102 sludge), a Sr/TRU washed precipitate produced from tank 241-AN-107 simulant, and a concentrated blended eluate simulant based upon eluates from processing 241-AZ-102 supernate.

Descriptive models for single-jet sluicing of sludge waste

International Nuclear Information System (INIS)

Erian, F.F.; Mahoney, L.A.; Terrones, G.

1997-12-01

Mobilization of sludge waste stored in underground storage tanks can be achieved safely and reliably by sluicing. In the project discussed in this report, the waste in Hanford single-shell Tank 241-C-106 will be mobilized by sluicing, retrieved by a slurry retrieval pump, and transferred via an 1800-ft slurry pipeline to Tank 241-AY-102. A sluicing strategy must be developed that ensures efficient use of the deployed configuration of the sluicing system: the nozzle(s) and the retrieval pump(s). Given a sluicing system configuration in a particular tank, it is desirable to prescribe the sequential locations at which the sludge will be mobilized and retrieved and the rate at which these mobilization and retrieval processes take place. In addition, it is necessary to know whether the retrieved waste slurry meets the requirements for cross-site slurry transport. Some of the physical phenomena that take place during mobilization and retrieval and certain aspects of the sluicing process are described in this report. First, a mathematical model gives (1) an idealized geometrical representation of where, within the confines of a storage tank containing a certain amount of settled waste, sludge can be removed and mobilized; and (2) a quantitative measure of the amount of sludge that can be removed during a sluicing campaign. A model describing an idealized water jet issuing from a circular nozzle located at a given height above a flat surface is also presented in this report. This dynamic water-jet model provides the basis for improving the geometrical sluicing model presented next. In this model the authors assume that the water jet follows a straight trajectory toward a target point on a flat surface. However, the water jet does not follow a straight line in the actual tank, and using the true trajectory will allow a more accurate estimate of the amount of disturbed material. Also, the authors hope that developing accurate force and pressure fields will lead to a better

Chemical species of plutonium in Hanford radioactive tank waste

International Nuclear Information System (INIS)

Barney, G.S.

1997-01-01

Large quantities of radioactive wastes have been generated at the Hanford Site over its operating life. The wastes with the highest activities are stored underground in 177 large (mostly one million gallon volume) concrete tanks with steel liners. The wastes contain processing chemicals, cladding chemicals, fission products, and actinides that were neutralized to a basic pH before addition to the tanks to prevent corrosion of the steel liners. Because the mission of the Hanford Site was to provide plutonium for defense purposes, the amount of plutonium lost to the wastes was relatively small. The best estimate of the amount of plutonium lost to all the waste tanks is about 500 kg. Given uncertainties in the measurements, some estimates are as high as 1,000 kg (Roetman et al. 1994). The wastes generally consist of (1) a sludge layer generated by precipitation of dissolved metals from aqueous wastes solutions during neutralization with sodium hydroxide, (2) a salt cake layer formed by crystallization of salts after evaporation of the supernate solution, and (3) an aqueous supernate solution that exists as a separate layer or as liquid contained in cavities between sludge or salt cake particles. The identity of chemical species of plutonium in these wastes will allow a better understanding of the behavior of the plutonium during storage in tanks, retrieval of the wastes, and processing of the wastes. Plutonium chemistry in the wastes is important to criticality and environmental concerns, and in processing the wastes for final disposal. Plutonium has been found to exist mainly in the sludge layers of the tanks along with other precipitated metal hydrous oxides. This is expected due to its low solubility in basic aqueous solutions. Tank supernate solutions do not contain high concentrations of plutonium even though some tanks contain high concentrations of complexing agents. The solutions also contain significant concentrations of hydroxide which competes with other

Sludge pumping in water treatment

International Nuclear Information System (INIS)

Solar Manuel, M. A.

2010-01-01

In water treatment processes is frequent to separate residual solids, with sludge shape, and minimize its volume in a later management. the technologies to applicate include pumping across pipelines, even to long distance. In wastewater treatment plants (WWTP), the management of these sludges is very important because their characteristics affect load losses calculation. Pumping sludge can modify its behavior and pumping frequency can concern treatment process. This paper explains advantages and disadvantages of different pumps to realize transportation sludge operations. (Author) 11 refs.

History of waste tank 16, 1959 through 1974

International Nuclear Information System (INIS)

Davis, T.L.; Tharin, D.W.; Jones, D.W.; Lohr, D.R.

1977-07-01

Tank 16 was placed in service as a receiver of fresh high heat waste (HW) on May 9, 1959, and was filled to capacity in May 1960. Approximately half the tank contents were transferred to tanks 14 and 15 during September and October 1960 because of leakage into the annulus. Use of tank 16 was resumed in October 1967 when authorization (TA 2-603) was obtained to receive LW, and the tank was filled to capacity by June 1968. Subsequently, supernate was removed from the tank, and a blend of fresh LW and evaporator bottoms was added. In March 1972, the supernate was transferred to tank 13 because leakage had resumed. The sludge was left in the tank bottom and the use of tank 16 for any additional waste storage was discontinued. In September 1960 liquid waste overflowed the annulus pan. Leakage essentially stopped after the tank liquid level was lowered below the middle horizontal weld. After exhaustive study, tank cracking and resultant leakage was concluded to have been caused by stress corrosion due to the action of NaOH or NaNO 3 on areas of high local stress in the steel plate such as welds. Samples of sludge, supernate, tank vapors, and leaked material in the annulus were analyzed, and tank temperature and radiation profiles were taken. Two disk samples were cut from the primary tank wall for metallurgical examination. Test coupons of various metals were exposed to tank 16 waste to aid new tank design and to study stress corrosion and hydrogen embrittlement. In addition, samples of SRP bedrock were placed in tank 16 to study reactions between bedrock and HW. 18 figures, 2 tables

Potential for criticality in Hanford tanks resulting from retrieval of tank waste

International Nuclear Information System (INIS)

Whyatt, G.A.; Sterne, R.J.; Mattigod, S.V.

1996-09-01

This report assesses the potential during retrieval operations for segregation and concentration of fissile material to result in a criticality. The sluicing retrieval of C-106 sludge to AY-102 and the operation of mixer pumps in SY-102 are examined in some detail. These two tanks (C-106, SY-102) were selected because of the near term plans for retrieval of these tanks and their high plutonium inventories relative to other tanks. Although all underground storage tanks are subcritical by a wide margin if assumed to be uniform in composition, the possibility retrieval operations could preferentially segregate the plutonium and locally concentrate it sufficiently to result in criticality was a concern. This report examines the potential for this segregation to occur

Toluene in sewage and sludge in wastewater treatment plants.

Science.gov (United States)

Mrowiec, Bozena

2014-01-01

Toluene is a compound that often occurs in municipal wastewater ranging from detectable levels up to 237 μg/L. Before the year 2000, the presence of the aromatic hydrocarbons was assigned only to external sources. The Enhanced Biological Nutrients Removal Processes (EBNRP) work according to many different schemes and technologies. For high-efficiency biological denitrification and dephosphatation processes, the presence of volatile fatty acids (VFAs) in sewage is required. VFAs are the main product of organic matter hydrolysis from sewage sludge. However, no attention has been given to other products of the process. It has been found that in parallel to VFA production, toluene formation occurred. The formation of toluene in municipal anaerobic sludge digestion processes was investigated. Experiments were performed on a laboratory scale using sludge from primary and secondary settling tanks of municipal treatment plants. The concentration of toluene in the digested sludge from primary settling tanks was found to be about 42,000 μg/L. The digested sludge supernatant liquor returned to the biological dephosphatation and denitrification processes for sewage enrichment can contain up to 16,500 μg/L of toluene.

Chemical modeling of waste sludges

International Nuclear Information System (INIS)

Weber, C.F.; Beahm, E.C.

1996-10-01

The processing of waste from underground storage tanks at the Oak Ridge National Laboratory (ORNL) and other facilities will require an understanding of the chemical interactions of the waste with process chemicals. Two aspects of sludge treatment should be well delineated and predictable: (1) the distribution of chemical species between aqueous solutions and solids, and (2) potential problems due to chemical interactions that could result in process difficulties or safety concerns. It is likely that the treatment of waste tank sludge will begin with washing, followed by basic or acidic leaching. The dissolved materials will be in a solution that has a high ionic strength where activity coefficients are far from unity. Activity coefficients are needed in order to calculate solubilities. Several techniques are available for calculating these values, and each technique has its advantages and disadvantages. The techniques adopted and described here is the Pitzer method. Like any of the methods, prudent use of this approach requires that it be applied within concentration ranges where the experimental data were fit, and its use in large systems should be preceded by evaluating subsystems. While much attention must be given to the development of activity coefficients, other factors such as coprecipitation of species and Ostwald ripening must also be considered when one aims to interpret results of sludge tests or to predict results of treatment strategies. An understanding of sludge treatment processes begins with the sludge tests themselves and proceeds to a general interpretation with the aid of modeling. One could stop with only data from the sludge tests, in which case the table of data would become an implicit model. However, this would be a perilous approach in situations where processing difficulties could be costly or result in concerns for the environment or health and safety

Heat pipe cooling system for underground, radioactive waste storage tanks

International Nuclear Information System (INIS)

Cooper, K.C.; Prenger, F.C.

1980-02-01

An array of 37 heat pipes inserted through the central hole at the top of a radioactive waste storage tank will remove 100,000 Btu/h with a heat sink of 70 0 F atmospheric air. Heat transfer inside the tank to the heat pipe is by natural convection. Heat rejection to outside air utilizes a blower to force air past the heat pipe condenser. The heat pipe evaporator section is axially finned, and is constructed of stainless steel. The working fluid is ammonia. The finned pipes are individually shrouded and extend 35 ft down into the tank air space. The hot tank air enters the shroud at the top of the tank and flows downward as it is cooled, with the resulting increased density furnishing the pressure difference for circulation. The cooled air discharges at the center of the tank above the sludge surface, flows radially outward, and picks up heat from the radioactive sludge. At the tank wall the heated air rises and then flows inward to comple the cycle

Application of contact stabilization activated sludge for enhancing biological phosphorus removal (EBPR in domestic wastewater

Directory of Open Access Journals (Sweden)

Ehab M. Rashed

2014-04-01

Full Text Available The experiment has been performed in order to investigate the effect of using contact stabilization activated sludge as an application of enhancing biological phosphorous removal (EBPR by using contact tank as a phosphorus uptake zone and using thickening tank as a phosphorus release zone. The study involved the construction of a pilot plant which was setup in Quhafa waste water treatment plant (WWTP that included contact, final sedimentation, stabilization and thickening tanks, respectively with two returns sludge in this system one of them to contact tank and another to stabilization tank. Then observation of the uptake and release of total phosphorus by achievement through two batch test using sludge samples from thickener and final sedimentations. Results showed the removal efficiencies of COD, BOD and TP for this pilot plant with the range of 94%, 85.44% and 80.54%, respectively. On the other hand the results of batch tests showed that the reason of high ability of phosphorus removal for this pilot plant related to the high performance of microorganisms for phosphorus accumulating. Finally the mechanism of this pilot plant depends on the removal of the phosphorus from the domestic waste water as a concentrated TP solution from the supernatant above the thickening zone not through waste sludge like traditional systems.

Determining the Release of Radionuclides from Tank 18F Waste Residual Solids: FY2016 Report

Energy Technology Data Exchange (ETDEWEB)

King, William D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hobbs, David T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-08-12

Pore water leaching studies were conducted on actual Savannah River Site (SRS) Tank 18F residual waste solids to support Liquid Waste tank closure efforts. A test methodology was developed during previous simulant testing to produce slurries of tank residual solids and grout-representative solids in grout pore water solutions (based on SRS groundwater compositions) with pH and E_h values expected during the aging of the closed waste tank. The target conditions are provided below where the initial pore water has a reducing potential and a relatively high pH (Reducing Region II). The pore water is expected to become increasingly oxidizing with time (Oxidizing Region II) and during the latter stages of aging (Oxidizing Region III) the pH is expected to decrease. For the reducing case, tests were conducted with both unwashed and washed Tank 18F residual solids. For the oxidizing cases (Oxidizing Regions II and III), all samples were washed with simulated grout pore water solutions prior to testing, since it is expected that these conditions will occur after considerable pore water solution has passed through the system. For the reducing case, separate tests were conducted with representative ground grout solids and with calcium carbonate reagent, which is the grout phase believed to be controlling the pH. Ferrous sulfide (FeS) solids were also added to the reducing samples to lower the slurry E_h value. Calcium carbonate solids were used as the grout-representative solid phase for each of the oxidizing cases. Air purge-gas with and without CO₂ removed was transferred through the oxidizing test samples and nitrogen purge-gas was transferred through the reducing test samples during leach testing. The target pH values were achieved to within 0.5 pH units for all samples. Leaching studies were conducted over an E_h range of approximately 0.7 V. However, the highest and lowest E_h values achieved of ~+0.5 V and ~-0.2 V were

Old hydrofracture facility tanks contents removal action operations plan at the Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 1: Text

International Nuclear Information System (INIS)

1998-05-01

This Operations Plan summarizes the operating activities for transferring contents of five low-level (radioactive) liquid waste storage tanks associated with the Old Hydrofracture Facility (OHF) to the Melton Valley Storage Tanks (MVST) for secure storage. The transfer will be accomplished through sluicing and pumping operations which are designed to pump the slurry in a closed circuit system using a sluicing nozzle to resuspend the sludge. Once resuspended, the slurry will be transferred to the MVST. The report documenting the material transfer will be prepared after transfer of the tank materials has been completed. The OBF tanks contain approximately 52,600 gal (199,000 L) of low-level radioactive waste consisting of both sludge and supernatant. This material is residual from the now-abandoned grout injection operations conducted from 1964 to 1980. Total curie content is approximately 30,000 Ci. A sluicing and pumping system has been specifically designed for the OHF tanks contents transfer operations. This system is remotely operated and incorporates a sluicing nozzle and arm (Borehole Miner) originally designed for use in the mining industry. The Borehole Miner is an in-tank device designed to deliver a high pressure jet spray via an extendable nozzle. In addition to removing the waste from the tanks, the use of this equipment will demonstrate applicability for additional underground storage tank cleaning throughout the U.S. Department of Energy complex. Additional components of the complete sluicing and pumping system consist of a high pressure pumping system for transfer to the MVST, a low pressure pumping system for transfer to the recycle tank, a ventilation system for providing negative pressure on tanks, and instrumentation and control systems for remote operation and monitoring

Waste mixing and diluent selection for the planned retrieval of Hanford Tank 241-SY-102: A preliminary assessment

International Nuclear Information System (INIS)

Onishi, Y.; Hudson, J.D.

1996-01-01

This preliminary assessment documents a set of analyses that were performed to determine the potential for Hanford waste Tank 241-SY-102 waste properties to be adversely affected by mixing the current tank contents or by injecting additional diluent into the tank during sludge mobilization. As a part of this effort, the effects of waste heating that will occur as a result of mixer pump operations are also examined. Finally, the predicted transport behavior of the resulting slurries is compared with the waste acceptance criteria for the Cross-Site Transfer System (CSTS). This work is being performed by Pacific Northwest National Laboratory in support of Westinghouse Hanford Company's W-211 Retrieval Project. We applied the equilibrium chemical code, GMIN, to predict potential chemical reactions. We examined the potential effects of mixing the current tank contents (sludge and supernatant liquid) at a range of temperatures and, separately, of adding pure water at a volume ratio of 1:2:2 (sludge:supernatant liquid:water) as an example of further diluting the current tank contents. The main conclusion of the chemical modeling is that mixing the sludge and the supernate (with or without additional water) in Tank 241-SY-102 dissolves all sodium-containing solids (i.e., NaNO 3 (s), thenardite, NaF(s), and halite), but does not significantly affect the amorphous Cr(OH) 3 and calcite phase distribution. A very small amount of gibbsite [Al(OH) 3 (s)] might precipitate at 25 degrees C, but a somewhat larger amount of gibbsite is predicted to dissolve at the higher temperatures. In concurrence with the reported tank data, the model affirmed that the interstitial solution within the sludge is saturated with respect to many of the solids species in the sludge, but that the supernatant liquid is not in saturation with many of major solids species in sludge. This indicates that a further evaluation of the sludge mixing could prove beneficial

Tank 241-AZ-102 tank characterization plan

International Nuclear Information System (INIS)

Schreiber, R.D.

1995-01-01

The Defense Nuclear Facilities Safety Board has advised the DOE to concentrate the near-term sampling and analysis activities on identification and resolution of safety issues. The Data Quality Objective (DQO) process was chosen as a tool to be used in the resolution of safety issues. As a result, a revision in the Federal Facilities Agreement and Consent Order (Tri-Party Agreement) milestone M-44 has been made, which states that ''A Tank Characterization Plan (TCP) will also be developed for each double-shell tank (DST) and single-shell tank (SST) using the DQO process ... Development of TCPs by the DQO process is intended to allow users to ensure their needs will be met and that resources are devoted to gaining only necessary information''. This document satisfies that requirement for tank 241-AZ-102 (AZ-102) sampling activities. Tank AZ-102 is currently a non-Watch List tank, so the only DQOs applicable to this tank are the safety screening DQO and the compatibility DQO, as described below. The current contents of Tank AZ-102, as of October 31, 1994, consisted of 3,600 kL (950 kgal) of dilute non-complexed waste and aging waste from PUREX (NCAW, neutralized current acid waste). Tank AZ-102 is expected to have two primary layers. The bottom layer is composed of 360 kL of sludge, and the top layer is composed of 3,240 kL of supernatant, with a total tank waste depth of approximately 8.9 meters

Reuse of acid coagulant-recovered drinking waterworks sludge residual to remove phosphorus from wastewater

Science.gov (United States)

Yang, Lan; Wei, Jie; Zhang, Yumei; Wang, Jianli; Wang, Dongtian

2014-06-01

Acid coagulant-recovered drinking waterworks sludge residual (DWSR) is a waste product from drinking waterworks sludge (DWS) treatment with acid for coagulant recovery. In this study, we evaluated DWSR as a potential phosphorus (P) removing material in wastewater treatment by conducting a series of batch and semi-continuous tests. Batch tests were carried out to study the effects of pH, initial concentration, and sludge dose on P removal. Batch test results showed that the P removal efficiency of DWSR was highly dependent on pH. Calcinated DWSR (C-DWSR) performed better in P removal than DWSR due to its higher pH. At an optimum initial pH value of 5-6 and a sludge dose of 10 g/L, the P removal rates of DWSR and DWS decreased from 99% and 93% to 84% and 14%, respectively, and the specific P uptake of DWSR and DWS increased from 0.19 and 0.19 mg P/g to 33.60 and 5.72 mg P/g, respectively, when the initial concentration was increased from 2 to 400 mg/L. The effective minimum sludge doses of DWSR and DWS were 0.5 g/L and 10 g/L, respectively, when the P removal rates of 90% were obtained at an initial concentration of 10 mg/L. Results from semi-continuous test indicated that P removal rates over 99% were quickly achieved for both synthetic and actual wastewater (lake water and domestic sewage). These rates could be maintained over a certain time under a certain operational conditions including sludge dose, feed flow, and initial concentration. The physicochemical properties analysis results showed that the contents of aluminum (Al) and iron (Fe) in DWSR were reduced by 50% and 70%, respectively, compared with DWS. The insoluble Al and Fe hydroxide in DWS converted into soluble Al and Fe in DWSR. Metal leaching test results revealed that little soluble Al and Fe remained in effluent when DWSR was used for P removal. We deduced that chemical precipitation might be the major action for P removal by DWSR and that adsorption played only a marginal role.

Influence of chemical sprinkle on the processes in activated tank of wastewater treatment

Directory of Open Access Journals (Sweden)

Milan Búgel

2012-12-01

Full Text Available The research deals with processes occurring in the activation tank during the snow-melt inflow of chemical component of roadsalt. Chemical composition of the suspension in the activation tank is changing following the metabolism of organisms and chemicalcomposition of the influent wastewater. Sludge and wastewater in nitrification tail of the activation tank has higher conductivity, highercontents of chloride, higher sludge index and other characteristics are changing during snow – melt. The amount of the inflow road saltis a determining factor of lyses of microorganism cells.

Sludge Treatment and Extraction Technology Development: Results of FY 1993 studies

International Nuclear Information System (INIS)

Lumetta, G.J.; Wagner, M.J.; Barrington, R.J.; Rapko, B.M.; Carlson, C.D.

1994-03-01

This report describes experimental results from work conducted in FY 1993 under the Sludge Treatment and Extraction Technology Development Task of the Tank Waste Remediation System (TWRS) Pretreatment Technology Development Project at Pacific Northwest Laboratory (PNL). Experiments were conducted in the following six general areas: (1) sludge washing, (2) sludge leaching, (3) sludge dissolution, (4) actinide separation by solvent extraction and extraction chromatography, (5) Sr separation by solvent extraction, and (6) extraction of Cs from acidic solution

Investigation of cooling coil corrosion in storage tanks for radioactive waste

International Nuclear Information System (INIS)

Ondrejcin, R.S.

1978-01-01

The high frequency of cooling coil leaks observed in high-heat waste storage tanks soon after sludge removal operations is attributed to pitting, according to laboratory corrosion studies. Experiments show that the most likely series of events leading to coil leakage is (1) excessive dilution of basic nitrite in the supernate, (2) initiation of attack in crevices due to oxygen depletion cells, and (3) acceleration of the attack by sulfate dissolved from the sludge. When sludge was slurried with water, the interstitial liquid was diluted. Nitrite, the anodic inhibitor that prevented attack on coils and tanks in normal operation when its concentration was 0.5 to 3.0M, could accelerate attack when diluted to 10 -4 to 10 -3 M. Attack was presumably initiated at oxygen depletion cells. The presence of sulfate, leached from the sludge, produced a conductive solution that could produce high current densities at the corroding steel surface. The proposed series of events leading to coil leakage agrees with the observations previously made on one leaking coil removed from Tank 2F after sludge removal in 1967. Examination revealed pitting that had originated on the outside of the coils. This pitting was attributed to oxygen depletion cells in coil crevices. To prevent recurrence of pitting attack on cooling coils during future sludge removal operations, the sludge should be slurried (1) with waste diluted less than one hundredfold with water, or (2) with a 500-ppm nitrite-H 2 O solution at pH 12. Either method should preclude pitting damage to the coils

Pump Jet Mixing and Pipeline Transfer Assessment for High-Activity Radioactive Wastes in Hanford Tank 241-AZ-102

Energy Technology Data Exchange (ETDEWEB)

Y Onishi; KP Recknagle; BE Wells

2000-08-09

The authors evaluated how well two 300-hp mixer pumps would mix solid and liquid radioactive wastes stored in Hanford double-shell Tank 241-AZ-102 (AZ-102) and confirmed the adequacy of a three-inch (7.6-cm) pipeline system to transfer the resulting mixed waste slurry to the AP Tank Farm and a planned waste treatment (vitrification) plant on the Hanford Site. Tank AZ-102 contains 854,000 gallons (3,230 m{sup 3}) of supernatant liquid and 95,000 gallons (360 m{sup 3}) of sludge made up of aging waste (or neutralized current acid waste). The study comprises three assessments: waste chemistry, pump jet mixing, and pipeline transfer. The waste chemical modeling assessment indicates that the sludge, consisting of the solids and interstitial solution, and the supernatant liquid are basically in an equilibrium condition. Thus, pump jet mixing would not cause much solids precipitation and dissolution, only 1.5% or less of the total AZ-102 sludge. The pump jet mixing modeling indicates that two 300-hp mixer pumps would mobilize up to about 23 ft (7.0 m) of the sludge nearest the pump but would not erode the waste within seven inches (0.18 m) of the tank bottom. This results in about half of the sludge being uniformly mixed in the tank and the other half being unmixed (not eroded) at the tank bottom.

Pump Jet Mixing and Pipeline Transfer Assessment for High-Activity Radioactive Wastes in Hanford Tank 241-AZ-102

International Nuclear Information System (INIS)

Onishi, Y.; Recknagle, K.P.; Wells, B.E.

2000-01-01

The authors evaluated how well two 300-hp mixer pumps would mix solid and liquid radioactive wastes stored in Hanford double-shell Tank 241-AZ-102 (AZ-102) and confirmed the adequacy of a three-inch (7.6-cm) pipeline system to transfer the resulting mixed waste slurry to the AP Tank Farm and a planned waste treatment (vitrification) plant on the Hanford Site. Tank AZ-102 contains 854,000 gallons (3,230 m 3 ) of supernatant liquid and 95,000 gallons (360 m 3 ) of sludge made up of aging waste (or neutralized current acid waste). The study comprises three assessments: waste chemistry, pump jet mixing, and pipeline transfer. The waste chemical modeling assessment indicates that the sludge, consisting of the solids and interstitial solution, and the supernatant liquid are basically in an equilibrium condition. Thus, pump jet mixing would not cause much solids precipitation and dissolution, only 1.5% or less of the total AZ-102 sludge. The pump jet mixing modeling indicates that two 300-hp mixer pumps would mobilize up to about 23 ft (7.0 m) of the sludge nearest the pump but would not erode the waste within seven inches (0.18 m) of the tank bottom. This results in about half of the sludge being uniformly mixed in the tank and the other half being unmixed (not eroded) at the tank bottom

Remote Water Lance Technology for Cleaning Waste Tanks

International Nuclear Information System (INIS)

Lehr, R.M.; Owen, J.R.; Mangold, F.E.

2006-01-01

This paper describes the use of remote water lances for cleaning sludge or solidified heel materials from waste tanks. S.A.Robotics has developed a long arm retrieval system to deploy ultra-high pressure water lances and vacuum recovery systems for tank cleanup operations. This system uses remote-operated telescoping long arms with light weight, high strength materials, innovative high capacity joint designs, and multiple degrees of freedom to deploy tank cleaning heads to all areas within the tanks. Arm designs can be scaled and adjusted to suit even the largest tanks. (authors)

Investigation on the fast co-pyrolysis of sewage sludge with biomass and the combustion reactivity of residual char.

Science.gov (United States)

Deng, Shuanghui; Tan, Houzhang; Wang, Xuebin; Yang, Fuxin; Cao, Ruijie; Wang, Zhao; Ruan, Renhui

2017-09-01

Gaining the valuable fuels from sewage sludge is a promising method. In this work, the fast pyrolysis characteristics of sewage sludge (SS), wheat straw (WS) and their mixtures in different proportions were carried out in a drop-tube reactor. The combustion reactivity of the residual char obtained was investigated in a thermogravimetric analyzer (TGA). Results indicate that SS and WS at different pyrolysis temperatures yielded different characteristic gas compositions and product distributions. The co-pyrolysis of SS with WS showed that there existed a synergistic effect in terms of higher gas and bio-oil yields and lower char yield, especially at the WS adding percentage of 80wt%. The addition of WS to SS increased the carbon content in the SS char and improved char porous structures, resulting in an improvement in the combustion reactivity of the SS char. The research results can be used to promote co-utilization of sewage sludge and biomass. Copyright © 2017. Published by Elsevier Ltd.

Rheology of sludge-slurry grouts

International Nuclear Information System (INIS)

McDaniel, E.W.

1980-10-01

A series of rheograms was developed that relates the critical velocity (velocity where flow changes from laminar to turbulent) of a cementitious grout that incorporates a suspended sludge-slurry to the critical velocity of a reference grout made with a simulated waste solution. The sludge that is now in the Gunite waste tanks at the Oak Ridge National Laboratory (ORNL) will be suspended and pumped to the new waste storage tanks in Melton Valley. The sludge will then be blended with a cement mix base to form a grout which will be injected underground by the shale fracturing process. This report describes the materials, equipment, and techniques used in the laboratory studies to suspend sludges and mix sludge-slurry grouts that have flow properties similar to those of current shale fracturing grouts. Bentonite clay is an effective suspender in dilute NaNO 3 solutions; 15 wt % solids can be suspended with 2.0 wt % bentonite in a 0.1 M NaNO 3 solution. Other suspending materials were evaluated, but bentonite gave the best results. If a slurry grout becomes too viscous to pump, methods must be available to thin the mixture. A number of thinners, friction reducers, and plasticizers were examined. Q-Broxin, a thinner supplied by Baroid, reduced the velocity of a grout required for turbulent flow in a 5.0-cm (2-in.)-diam tube from 1.76 to 1.20 m/s (5.79 to 3.95 ft/s); FX-32C, a plasticizer supplied by Fox Industries, Inc., reduced the velocity from 1.76 to 0.75 m/s

Cryograb: A Novel Approach to the Retrieval of Waste from Underground Storage Tanks - 13501

Energy Technology Data Exchange (ETDEWEB)

O' Brien, Luke; Baker, Stephen; Bowen, Bob [UK National Nuclear Laboratory, Chadwick House, Warrington (United Kingdom); Mallick, Pramod; Smith, Gary [US Department of Energy (United States); King, Bill [Savannah River National Laboratory (United States); Judd, Laurie [NuVision Engineering (United States)

2013-07-01

The UK's National Nuclear Laboratory (NNL) is investigating the use of cryogenic technology for the recovery of nuclear waste. Cryograb, freezing the waste on a 'cryo-head' and then retrieves it as a single mass which can then be treated or stabilized as necessary. The technology has a number of benefits over other retrieval approaches in that it minimizes sludge disturbance thereby reducing effluent arising and it can be used to de-water, and thereby reduce the volume of waste. The technology has been successfully deployed for a variety of nuclear and non-nuclear waste recovery operations. The application of Cryograb for the recovery of waste from US underground storage tanks is being explored through a US DOE International Technology Transfer and Demonstration programme. A sample deployment being considered involves the recovery of residual mounds of sludge material from waste storage tanks at Savannah River. Operational constraints and success criteria were agreed prior to the completion of a process down selection exercise which specified the preferred configuration of the cryo-head and supporting plant. Subsequent process modeling identified retrieval rates and temperature gradients through the waste and tank infrastructure. The work, which has been delivered in partnership with US DOE, SRNL, NuVision Engineering and Frigeo AB has demonstrated the technical feasibility of the approach (to TRL 2) and has resulted in the allocation of additional funding from DOE to take the programme to bench and cold pilot-scale trials. (authors)

Processed wastewater sludge for improvement of mechanical properties of concretes

Energy Technology Data Exchange (ETDEWEB)

Barrera-Diaz, Carlos, E-mail: cbd0044@yahoo.com [Centro Conjunto de Investigacion en Quimica Sustentable, Universidad Autonoma del Estado de Mexico - Universidad Nacional Autonoma de Mexico (UAEM-UNAM), Carretera Toluca-Atlacomulco, km 14.5, Unidad El Rosedal, C.P. 50200, Toluca, Edo. de Mexico (Mexico); Martinez-Barrera, Gonzalo [Laboratorio de Investigacion y Desarrollo de Materiales Avanzados (LIDMA), Facultad de Quimica, Universidad Autonoma del Estado de Mexico, Carretera Toluca-Atlacomulco, Km.12, San Cayetano C.P. 50200, Toluca, Edo. de Mexico (Mexico); Gencel, Osman [Civil Engineering Department, Faculty of Engineering, Bartin University, 74100 Bartin (Turkey); Bernal-Martinez, Lina A. [Centro Conjunto de Investigacion en Quimica Sustentable, Universidad Autonoma del Estado de Mexico - Universidad Nacional Autonoma de Mexico (UAEM-UNAM), Carretera Toluca-Atlacomulco, km 14.5, Unidad El Rosedal, C.P. 50200, Toluca, Edo. de Mexico (Mexico); Brostow, Witold [Laboratory of Advanced Polymers and Optimized Materials (LAPOM), Department of Materials Science and Engineering and Center for Advanced Research and Technology (CART), University of North Texas, 1150 Union Circle 305310, Denton, TX 76203-5017 (United States)

2011-08-15

Highlights: {yields} Electrochemical methods produce less amount of residual sludge as compared with chemical procedures. {yields} Wastewater sludge contains a large amount of water. {yields} The residual sludge is used to prepare cylinder specimen concrete. {yields} There are improvements in the elastic modulus of the concrete when is prepared with residual sludge. - Abstract: Two problems are addressed simultaneously. One is the utilisation of sludge from the treatment of wastewater. The other is the modification of the mechanical properties of concrete. The sludge was subjected to two series of treatments. In one series, coagulants were used, including ferrous sulphate, aluminium sulphate or aluminium polyhydroxychloride. In the other series, an electrochemical treatment was applied with several starting values of pH. Then, concretes consisting of a cement matrix, silica sand, marble and one of the sludges were developed. Specimens without sludge were prepared for comparison. Curing times and aggregate concentrations were varied. The compressive strength, compressive strain at yield point, and static and dynamic elastic moduli were determined. Diagrams of the compressive strength and compressive strain at the yield point as a function of time passed through the minima as a function of time for concretes containing sludge; therefore, the presence of sludge has beneficial effects on the long term properties. Some morphological changes caused by the presence of sludge are seen in scanning electron microscopy. A way of utilising sludge is thus provided together with a way to improve the compressive strain at yield point of concrete.