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Foaming in Hanford River Protection Project Waste Treatment Plant LAW Evaporation Processes - FY01 Summary Report

Description: The LAW evaporation processes currently being designed for the Hanford River Protection Project Waste Treatment Plant are subject to foaming. Experimental simulant studies have been conducted in an effort to achieve an effective antifoam agent suitable to mitigate such foaming.
Date: July 23, 2002
Creator: Calloway, T.B.
Partner: UNT Libraries Government Documents Department

Regulatory Off-Gas Analysis from the Evaporator of Hanford Simulated Waste Spiked with Organic Compounds

Description: After strontium/transuranics removal by precipitation followed by cesium/technetium removal by ion exchange, remaining low activity waste in the Hanford River Protection Project Waste Treatment Plant is to be concentrated by evaporation prior to being mixed with glass formers and vitrified. To provide a technical basis to permit the waste treatment facility, a relatively organic-rich Hanford Tank 241-AN-107 waste simulant was spiked with 14 target volatile, semi-volatile and pesticide compounds, and evaporated under vacuum in a bench-scale natural circulation evaporator fitted with an industrial stack off-gas sampler at the Savannah River Technology Center. An evaporator material balance for the target organics was calculated by combining liquid stream mass and analytical data with off-gas emissions estimates obtained using EPA SW-846 Methods.
Date: August 21, 2002
Creator: Calloway, T.B.
Partner: UNT Libraries Government Documents Department

Fate of IIT B52 Antiform Agent Across the Small Tank Tetraphenylborate Process

Description: The primary objective of these experiments was to determine the fate (partitioning) of the antifoam agent across the precipitation, concentration and washing cycles. A secondary objective of this experiment was to determine if insoluble aluminum formed during the STTP process.
Date: July 10, 2001
Creator: Calloway, T.B.
Partner: UNT Libraries Government Documents Department

Radioactive Waste Evaporation: Current Methodologies Employed for the Development, Design, and Operation of Waste Evaporators at the Savannah River Site and Hanford Waste Treatment Plant

Description: Evaporation of High level and Low Activity (HLW and LAW) radioactive wastes for the purposes of radionuclide separation and volume reduction has been conducted at the Savannah River and Hanford Sites for more than forty years. Additionally, the Savannah River Site (SRS) has used evaporators in preparing HLW for immobilization into a borosilicate glass matrix. This paper will discuss the methodologies, results, and achievements of the SRTC evaporator development program that was conducted in support of the SRS and Hanford WTP evaporator processes. The cross pollination and application of waste treatment technologies and methods between the Savannah River and Hanford Sites will be highlighted. The cross pollination of technologies and methods is expected to benefit the Department of Energy's Mission Acceleration efforts by reducing the overall cost and time for the development of the baseline waste treatment processes.
Date: September 11, 2003
Creator: Calloway, T.B.
Partner: UNT Libraries Government Documents Department

Laser Scanning Confocal Microscopic Investigations of Simulated Nuclear Waste Structures

Description: Researchers at the Department of Energy's Savannah River Technology Center are using advanced microscopy techniques to understand the effects of trace organic chemical additions on nuclear waste slurry flow properties. Trace organic chemicals, surfactants (rheology modifiers), are being used in all types of industries to modify the flow properties of various commercial chemicals. Nuclear waste treatment at the Department of Energy's weapons production facilities, Savannah River Site and Hanford Reservation, is limited by the viscosity of the nuclear waste slurries as the material is processed through a variety of waste treatment and immobilization processes. The picture was taken using a laser scanning confocal microscope.
Date: November 24, 2003
Creator: Calloway, T.B.
Partner: UNT Libraries Government Documents Department

Waste Feed Evaporation: Physical Properties and Solubility Determination

Description: Caustic adjustment of the UF recycle stream was required to prevent gel formation for the solutions tested. Actual amounts of caustic adjustment required will vary depending on the composition and volume ratios of the UF recycle. The concentration of recycles in the waste feed evaporator as required to blend with waste feed streams to provide a feed to the ultrafiltration process with a supernate specific gravity of 1.22 is feasible. No problems (such as severe foaming) were noted during the lab-scale testing that would preclude operation of the evaporator. The physical properties of the recycles and waste feed blends fit well to correlations based on sodium concentration and temperature. Evaporation of streams containing high levels of insoluble solids may lead to ''bumping'' or other undesirable behavior in the evaporator at insoluble solids. Sodium alumino-silicate solids were not noted in the evaporator feed or concentrate, but NAS did form in the blends of concentrated recycle and waste feeds. Strontium was found to precipitate during neutralization of the acid cleaning solution and remain precipitated during evaporation. Mercury was found to be significantly soluble in Envelope A simulants and the solubility of mercury increased during evaporation. No mercury was detected in the offgas system after evaporation using Envelope A simulants. Mercury was significantly less soluble in a simulant of AZ-102. Filtration of the Envelope A waste simulants was affected by the addition of recycle to the process, but the impact was primarily due to an increase in the amount of insoluble solids in the blended stream compared to the waste feed.
Date: August 25, 2003
Creator: Calloway, T.B.
Partner: UNT Libraries Government Documents Department

Characterization of Off Gas Flow Surges in the DWPF Melter

Description: The Defense Waste Processing Facility (DWPF) is currently producing radioactive canisters containing vitrified high-level waste. A slurry of high-level waste and glass frit is fed into a joule-heated melter where the mixture is dried, calcined, and melted. The off gases produced are treated in an off gas system designed to remove radioactive particulate and volatile components before exhausting clean gases to the environment. Surges in the flow of off gas can occur by various means, and must be accommodated by the melter off gas system. A method for calculating the magnitude of off gas surges is presented and applied to actual plant data. The melter off gas control system is shown to mitigate the effects of most flow surges without significant impact to plant operations.
Date: March 15, 1999
Creator: Calloway, T.B. Jr.
Partner: UNT Libraries Government Documents Department

Regulatory Off-Gas Analysis from the Evaporation of Hanford Simulated Waste Spiked with Organic Compounds

Description: After strontium/transuranics removal by precipitation followed by cesium/technetium removal by ion exchange, remaining low activity waste in the Hanford River Protection Project Waste Treatment Plant is to be concentrated by evaporation prior to being mixed with glass formers and vitrified. To provide a technical basis to permit the waste treatment facility, a relatively organic-rich Hanford Tank 241-AN-107 waste simulant was spiked with 14 target volatile, semi-volatile and pesticide compounds, and evaporated under vacuum in a bench-scale natural circulation evaporator fitted with an industrial stack off-gas sampler at the Savannah River Technology Center. An evaporator material balance for the target organics was calculated by combining liquid stream mass and analytical data with off-gas emissions estimates obtained using EPA SW-846 Methods. Volatile and light semi-volatile organic compounds in the waste simulant were found to largely exit through the condenser vent, while heavier semi-volatiles and pesticides generally remain in the evaporator concentrate. An OLI Environmental Simulation Program evaporator model successfully predicted operating conditions and the experimental distribution of the fed target organics exiting in the concentrate, condensate and off-gas streams with the exception of a few semi-volatile and pesticide compounds. Comparison with Henry's Law predictions suggests the OLI ESP model is constrained by available literature data.
Date: October 23, 2003
Creator: Calloway, T.B. Jr.
Partner: UNT Libraries Government Documents Department

Rheology Modifiers for Radioactive Waste Slurries

Description: The goals of this study were to determine if trace levels of chemical additives could be used to reduce the rheological characteristics of radioactive waste slurries, identify potential chemical additives for this work and future testing, test a limited set of chemical additive candidates on simulated radioactive wastes, and develop advanced techniques to visualize the internal slurry structure and particle-particle interaction within the slurry.
Date: February 19, 2003
Creator: Calloway, T.B. Jr.
Partner: UNT Libraries Government Documents Department

Analysis of the DWPF glass pouring system using neural networks

Description: Neural networks were used to determine the sensitivity of 39 selected Melter/Melter Off Gas and Melter Feed System process parameters as related to the Defense Waste Processing Facility (DWPF) Melter Pour Spout Pressure during the overall analysis and resolution of the DWPF glass production and pouring issues. Two different commercial neural network software packages were used for this analysis. Models were developed and used to determine the critical parameters which accurately describe the DWPF Pour Spout Pressure. The model created using a low-end software package has a root mean square error of {+-} 0.35 inwc (< 2% of the instrument`s measured range, R{sup 2} = 0.77) with respect to the plant data used to validate and test the model. The model created using a high-end software package has a R{sub 2} = 0.97 with respect to the plant data used to validate and test the model. The models developed for this application identified the key process parameters which contribute to the control of the DWPF Melter Pour Spout pressure during glass pouring operations. The relative contribution and ranking of the selected parameters was determined using the modeling software. Neural network computing software was determined to be a cost-effective software tool for process engineers performing troubleshooting and system performance monitoring activities. In remote high-level waste processing environments, neural network software is especially useful as a replacement for sensors which have failed and are costly to replace. The software can be used to accurately model critical remotely installed plant instrumentation. When the instrumentation fails, the software can be used to provide a soft sensor to replace the actual sensor, thereby decreasing the overall operating cost. Additionally, neural network software tools require very little training and are especially useful in mining or selecting critical variables from the vast amounts of data collected from ...
Date: August 5, 1997
Creator: Calloway, T.B. Jr.; Jantzen, C.M.; Medich, L. & Spennato, N.
Partner: UNT Libraries Government Documents Department

Physical Property Modeling of Concentrated Cesium Eluate Solutions, Part I - Derivation of Models

Description: Major analytes projected to be present in the Hanford Waste Treatment Plant cesium ion-exchange eluate solutions were identified from the available analytical data collected during radioactive bench-scale runs, and a test matrix of cesium eluate solutions was designed within the bounding concentrations of those analytes. A computer model simulating the semi-batch evaporation of cesium eluate solutions was run in conjunction with a multi-electrolyte aqueous system database to calculate the physical properties of each test matrix solution concentrated to the target endpoints of 80% and 100% saturation. The calculated physical properties were analyzed statistically and fitted into mathematical expressions for the bulk solubility, density, viscosity, heat capacity and volume reduction factor as a function of temperature and concentration of each major analyte in the eluate feed. The R{sup 2} of the resulting physical property models ranged from 0.89 to 0.99.
Date: September 15, 2005
Creator: Choi, A.S.; Pierce, R. A.; Edwards, T. B. & Calloway, T. B.
Partner: UNT Libraries Government Documents Department

Evaluation of Foaming and Antifoam Effectiveness During the WTP Oxidative Leaching Process

Description: The River Protection Project-Waste Treatment Plant (RPP-WTP) requested Savannah River National Laboratory (SRNL) to conduct small-scale foaming and antifoam testing using a Hanford waste simulant subjected to air sparging during oxidative leaching. The foaminess of Hanford tank waste solutions was previously demonstrated by SRNL during WTP evaporator foaming studies and in small scale air sparger studies. The commercial antifoam, Dow Corning Q2-3183A was recommended to mitigate the foam in the evaporators and in vessel equipped with pulse jet mixers and air spargers. Currently, WTP is planning to use air spargers in the HLW Lag Storage Vessels (HLP-VSL-00027A/B), the Ultrafiltration Vessels (UFP-VSL-00002A&amp;B), and the HLW Feed Blend Vessel (HLPVSL-00028) to assist the performance of the Pulse Jet Mixers (PJM). The previous air sparger antifoam studies conducted by SRNL researchers did not evaluate the hydrogen generation rate expected from antifoam additions or the effectiveness of the antifoam during caustic leaching or oxidative leaching. The fate of the various antifoam components and breakdown products in the WTP process under prototypic process conditions (temperature & radiation) was also not investigated. The effectiveness of the antifoam during caustic leaching, expected hydrogen generation rate associated with antifoam addition, and the fate of various antifoam components are being conducted under separate SRNL research tasks.
Date: October 11, 2005
Creator: Burket, P. R.; Jones, T. M.; White, T. L.; Crawford, C. L. & Calloway, T. B
Partner: UNT Libraries Government Documents Department

Development of a melter system for actinide vitrification. Revision 1

Description: The stabilization of actinides in glass was a technology considered for repository disposal of weapons-grade plutonium. Accelerated development efforts of a suitable glass composition (lanthanide borosilicate; LaBS) and melter system were completed in 1997. The other form involved in the down-selection process was a crystalline ceramic based on Synroc. As part of the glass development program, melter design activities and component testing were completed to demonstrate the feasibility of using glass as an immobilization medium. A prototypical melter was designed and built in 1997. The melter system centered on a Pt/Rh-alloy melter vessel and drain tube that were heated by two separate induction systems. An optional Pt/Rh stirrer was incorporated into the design to facilitate homogenization of the melt. Integrated powder feeding and off-gas systems completed the overall design. Concurrent with the design efforts, testing was conducted using a plutonium surrogate LaBS composition in an existing (near-scale) induction melter to demonstrate the feasibility of processing the LaBS glass on a production scale. Additionally, the drain tube configuration was successfully tested using a plutonium surrogate LaBS glass. The down-selection resulted in the selection of the ceramic option for future development. The successful testing of the induction melter system, however, showed that it is a viable technology for actinide vitrification. Currently, the melter system, complete with control and offgas components, is being successfully utilized to support the Americium/Curium vitrification program at the Savannah River Site.
Date: April 1998
Creator: Marshall, K. M.; Marra, J. C.; Coughlin, J. T.; Calloway, T. B.; Schumacher, R. F.; Zamecnik, J. R. et al.
Partner: UNT Libraries Government Documents Department

Development of the plutonium oxide vitrification system

Description: Repository disposal of plutonium in a suitable, immobilized form is being considered as one option for the disposition of surplus weapons-usable plutonium. Accelerated development efforts were completed in 1997 on two potential immobilization forms to facilitate downselection to one form for continued development. The two forms studied were a crystalline ceramic based on Synroc technology and a lanthanide borosilicate (LaBS) glass. As part of the glass development program, melter design activities and component testing were completed to demonstrate the feasibility of using glass as an immobilization medium. A prototypical melter was designed and built in 1997. The melter vessel and drain tube were constructed of a Pt/Rh alloy. Separate induction systems were used to heat the vessel and drain tube. A Pt/Rh stirrer was incorporated into the design to facilitate homogenization of the melt. Integrated powder feeding and off-gas systems completed the overall design. Concurrent with the design efforts, testing was conducted using a plutonium surrogate LaBS composition in an existing (near-scale) melter to demonstrate the feasibility of processing the LaBS glass on a production scale. Additionally, the drain tube configuration was successfully tested using a plutonium surrogate LaBS glass.
Date: January 1, 1998
Creator: Marshall, K.M.; Marra, J.C.; Coughlin, J.T.; Calloway, T.B.; Schumacher, R.F.; Zamecnik, J.R. et al.
Partner: UNT Libraries Government Documents Department

Hanford Supplemental Treatment: Literature and Modeling Review of SRS HLW Salt Dissolution and Fractional Crystallization

Description: In order to accelerate waste treatment and disposal of Hanford tank waste by 2028, the Department of Energy (DOE) and CH2M Hill Hanford Group (CHG), Inc. are evaluating alternative technologies which will be used in conjunction with the Waste Treatment Plant (WTP) to safely pretreat and immobilize the tank waste. Several technologies (Bulk Vitrification and Steam Reforming) are currently being evaluated for immobilizing the pretreated waste. Since the WTP does not have sufficient capacity to pretreat all the waste going to supplemental treatment by the 2028 milestone, two technologies (Selective Dissolution and Fractional Crystallization) are being considered for pretreatment of salt waste. The scope of this task was to: (1) evaluate the recent Savannah River Site (SRS) Tank 41 dissolution campaign and other literature to provide a more complete understanding of selective dissolution, (2) provide an update on the progress of salt dissolution and modeling activities at SRS, (3) investigate SRS experience and outside literature sources on industrial equipment and experimental results of previous fractional crystallization processes, and (4) evaluate recent Hanford AP104 boildown experiments and modeling results and recommend enhancements to the Environmental Simulation Program (ESP) to improve its predictive capabilities. This report provides a summary of this work and suggested recommendations.
Date: March 23, 2005
Creator: Choi, A. S.; Flach, G. P.; Martino, C. J.; Zamecnik, J. R.; Harris, M. K.; Wilmarth, W. R. et al.
Partner: UNT Libraries Government Documents Department

Final Report: RPP-WTP Semi-Integrated Pilot Plant

Description: In August 2004 the last of the SIPP task testing ended--a task that formally began with the issuance of the RPP-WTP Test Specification in June 2003. The planning for the task was a major effort in itself and culminated with the input of all stakeholders, DOE, Bechtel National, Inc., Washington Group International, in October 2003 at Hanford, WA (Appendix A). This report documents the activities carried out as a result of that planning. Campaign IV, the fourth and final step towards the Semi-Integrated Pilot Plant (SIPP) task, conducted by the Savannah River National Laboratory (SRNL) at the Savannah River Site, was to take the several recycle streams produced in Campaign III, the third step of the task, and combine them with other simulated recycle and chosen waste streams. (Campaign III was fed recycles from Campaign II, as Campaign II was fed by Campaign I.) The combined stream was processed in a fashion that mimicked the pretreatment operations of the DOE River Protection Project--Waste Treatment and Immobilization Plant (RPP-WTP) with the exception of the Ion Exchange Process. The SIPP task is considered semi-integrated because it only deals with the pretreatment operations of the RPP-WTP. That is, the pilot plant starts by receiving waste from the tank farm and ends when waste is processed to the point of being sent for vitrification. The resulting pretreated LAW and HLW simulants produced by the SIPP were shipped to VSL (Vitreous State Laboratory) and successfully vitrified in pilot WTP melters. Within the SIPP task these steps are referred to as Campaigns and there were four Campaigns in all. Campaign I, which is completely different than other campaigns, subjected a simulant of Hanford Tank 241-AY-102/C-106 (AY102) waste to cross-flow ultrafiltration only and in that process several important recycle streams were produced as a result of washing ...
Date: June 1, 2005
Creator: Duignan, M. R.; Adamson, D. J.; Calloway, T. B.; Fowley, M. D.; Qureshi, Z. H.; Steimke, J. L. et al.
Partner: UNT Libraries Government Documents Department