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Comparison of simulants to actual neutralized current acid waste: Process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

Description: A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs have been established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste is being performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions.
Date: April 1, 1996
Creator: Morrey, E.V. & Tingey, J.M.
Partner: UNT Libraries Government Documents Department

Comparison of simulants to actual neutralized current acid waste: process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

Description: A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs were established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste was performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property ,models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions.
Date: October 1, 1996
Creator: Morrey, E.V.; Tingey, J.M. & Elliott, M.L.
Partner: UNT Libraries Government Documents Department

Offgas characterization from the radioactive NCAW core sample (102-AZ-C1) and simulant during HWVP feed preparation testing: Letter report

Description: The primary objective of the Radioactive Process/Product Laboratory Testing (RPPLT) is to provide preliminary confirmation that the nonradioactive waste feed stimulant recipe is adequate for addressing the testing needs of design, safety, waste form qualification (WFO), and permitting of the Hanford Waste Vitrification Plant HWVP). The information contained In this letter report specifically addresses offgas production during the formating, digestion, and recycle addition of the third Neutralized Current Acid Waste (NCAW) core sample and core stimulant. Testing was conducted using a laboratory-scale version of the HWVP flowsheet.
Date: March 1, 1996
Creator: Langowski, M.H.; Morrey, E.V.; Tingey, J.M. & Beckette, M.R.
Partner: UNT Libraries Government Documents Department

Characterization of the first core sample of neutralized current acid waste from double-shell tank 101-AZ

Description: In FY 1989, Westinghouse Hanford Company (WHC) successfully obtained four core samples (totaling seven segments) of neutralized current acid waste (NCAW) from double-shell tanks (DSTs) 101-AZ and 102-AZ. A segment was a 19-in.-long and 1-in.-diameter cylindrical sample of waste. A core sample consisted of enough 19-in.-long segments to obtain the waste of interest. Three core samples were obtained from DST 101-AZ and one core sample from DST 102-AZ. Two DST 101-AZ core samples consisted of two segments per core, and the third core sample consisted of only one segment. The third core consisted of the solids from the bottom of the tank and was used to determine the relative abrasiveness of this NCAW. The DST 102-AZ core sample consisted of two segments. The core samples were transported to the Pacific Northwest Laboratory (PNL), where the waste was extruded from its sampler and extensively characterized. A characterization plan was followed that simulated the processing of the NCAW samples through retrieval, pretreatment and vitrification process steps. Physical, rheological, chemical and radiochemical properties were measured throughout the process steps. The characterization of the first core sample from DST 101-AZ was completed, and the results are provided in this report. The results for the other core characterizations will be reported in future reports. 3 refs., 13 figs., 10 tabs.
Date: September 1, 1989
Creator: Peterson, M E; Scheele, R D & Tingey, J M
Partner: UNT Libraries Government Documents Department

Laboratory-scale vitrification and leaching of Hanford high-level waste for the purpose of simulant and glass property models validation

Description: The Hanford Waste Vitrification Plant (HWVP) is being built to process the high-level and TRU waste into canistered glass logs for disposal in a national repository. Testing programs have been established within the Project to verify process technology using simulated waste. A parallel testing program with actual radioactive waste is being performed to confirm the validity of using simulates and glass property models for waste form qualification and process testing. The first feed type to be processed by and the first to be tested on a laboratory-scale is pretreated neutralized current acid waste (NCAW). The NCAW is a neutralized high-level waste stream generated from the reprocessing of irradiated nuclear fuel in the Plutonium and Uranium Extraction (PUREX) Plant at Hanford. As part of the fuel reprocessing, the high-level waste generated in PUREX was denitrated with sugar to form current acid waste (CAW). Sodium hydroxide and sodium nitrite were added to the CAW to minimize corrosion in the tanks, thus yielding neutralized CAW. The NCAW contains small amounts of plutonium, fission products from the irradiated fuel, stainless steel corrosion products, and iron and sulfate from the ferrous sulfamate reductant used in the PUREX process. This paper will discuss the results and status of the laboratory-scale radioactive testing.
Date: February 1, 1993
Creator: Morrey, E.V.; Elliott, M.L. & Tingey, J.M.
Partner: UNT Libraries Government Documents Department

Characterization of Hanford tank wastes containing ferrocyanides

Description: Currently, 17 storage tanks on the Hanford site that are believed to contain > 1,000 gram moles (465 lbs) of ferrocyanide compounds have been identified. Seven other tanks are classified as ferrocyanide containing waste tanks, but contain less than 1,000 gram moles of ferrocyanide compounds. These seven tanks are still included as Hanford Watch List Tanks. These tanks have been declared an unreviewed safety question (USQ) because of potential thermal reactivity hazards associated with the ferrocyanide compounds and nitrate and nitrite. Hanford tanks with waste containing > 1,000 gram moles of ferrocyanide have been sampled. Extensive chemical, radiothermical, and physical characterization have been performed on these waste samples. The reactivity of these wastes were also studied using Differential Scanning Calorimetry (DSC) and Thermogravimetric analysis. Actual tank waste samples were retrieved from tank 241-C-112 using a specially designed and equipped core-sampling truck. Only a small portion of the data obtained from this characterization effort will be reported in this paper. This report will deal primarily with the cyanide and carbon analyses, thermal analyses, and limited physical property measurements.
Date: February 1, 1993
Creator: Tingey, J.M.; Matheson, J.D.; McKinley, S.G.; Jones, T.E. & Pool, K.H.
Partner: UNT Libraries Government Documents Department

Chemical reactivity of potential ferrocyanide precipitates in Hanford tanks with nitrates and nitrites

Description: Ferrocyanide-bearing wastes were produced at the Hanford Site during the 1950s. Safe storage of these wastes has recently drawn increased attention. As a result of these concerns, the Pacific Northwest Laboratory was chartered to investigate the chemical reactivity and explosivity of the ferrocyanide bearing wastes. WE have investigated the thermal sensitivity of synthetic wastes and ferrocyanides and observed oxidation at 130{degrees}C and explosions down to 295{degrees}C. Coupled with thermodynamic calculations, these thermal studies have also shown a dependence of the reactivity on the synthetic waste composition, which is dependent on the solids settling behavior.
Date: March 1, 1992
Creator: Scheele, R.D.; Tingey, J.M.; Lilga, M.A.; Burger, L.L. & Hallen, R.T.
Partner: UNT Libraries Government Documents Department

Slurry growth, gas retention, and flammable gas generation by Hanford radioactive waste tanks: Synthetic waste studies, FY 1991

Description: Of 177 high-level waste storage tanks on the Hanford Site, 23 have been placed on a safety watch list because they are suspected of producing flammable gases in flammable or explosive concentrate. One tankin particular, Tank 241-SY-101 (Tank 101-SY), has exhibited slow increases in waste volume followed by a rapid decrease accompanied by venting of large quantities of gases. The purpose of this study is to help determine the processes by which flammable gases are produced, retained, and eventually released from Tank 101-SY. Waste composition data for single- and double-shell waste tanks on the flammable gas watch listare critically reviewed. The results of laboratory studies using synthetic double-shell wastes are summarized, including physical and chemical properties of crusts that are formed, the stoichiometry and rate ofgas generation, and mechanisms responsible for formation of a floating crust.
Date: August 1, 1992
Creator: Bryan, S.A.; Pederson, L.R.; Ryan, J.L.; Scheele, R.D. & Tingey, J.M.
Partner: UNT Libraries Government Documents Department

Slurry growth, gas retention, and flammable gas generation by Hanford radioactive waste tanks: Synthetic waste studies, FY 1991

Description: Of 177 high-level waste storage tanks on the Hanford Site, 23 have been placed on a safety watch list because they are suspected of producing flammable gases in flammable or explosive concentrate. One tankin particular, Tank 241-SY-101 (Tank 101-SY), has exhibited slow increases in waste volume followed by a rapid decrease accompanied by venting of large quantities of gases. The purpose of this study is to help determine the processes by which flammable gases are produced, retained, and eventually released from Tank 101-SY. Waste composition data for single- and double-shell waste tanks on the flammable gas watch listare critically reviewed. The results of laboratory studies using synthetic double-shell wastes are summarized, including physical and chemical properties of crusts that are formed, the stoichiometry and rate ofgas generation, and mechanisms responsible for formation of a floating crust.
Date: August 1, 1992
Creator: Bryan, S. A.; Pederson, L. R.; Ryan, J. L.; Scheele, R. D. & Tingey, J. M.
Partner: UNT Libraries Government Documents Department

Tank characterization report for single-shell Tank B-201

Description: The purpose of this report is to characterize the waste in single shell Tank B-201. Characterization includes the determination of the physical, chemical (e.g., concentrations of elements and organic species), and radiological properties of the waste. These determinations are made using analytical results from B-201 core samples as well as historical information about the tank. The main objective is to determine average waste properties: but in some cases, concentrations of analytes as a function of depth were also determined. This report also consolidates the available historical information regarding Tank B-201, arranges the analytical information from the recent core sampling in a useful format, and provides an interpretation of the data within the context of what is known about the tank.
Date: September 1, 1994
Creator: Heasler, P.G.; Remund, K.M.; Tingey, J.M.; Baird, D.B. & Ryan, F.M.
Partner: UNT Libraries Government Documents Department

Hanford ferrocyanide waste chemistry and reactivity preliminary catalyst and initiator screening studies

Description: During the 1950s, ferrocyanide was used to scavenge radiocesium from aqueous nitrate-containing Hanford wastes. During the production of defense materials and while these wastes were stored in high-level waste tanks at the Hanford Site, some of these wastes were likely mixed with other waste constituents and materials. Recently, Pacific Northwest Laboratory (PNL) was commissioned by Westinghouse Hanford Company (WHC) to investigate the chemical reactivity of these ferrocyanide-bearing wastes. Because of known or potential thermal reactivity hazards associated with ferrocyanide- and nitrate-bearing wastes, and because of the potential for different materials to act as catalysts or initiators of the reactions about which there is concern, we at PNL have begun investigating the effects of the other potential waste constituents. This report presents the results of a preliminary screening study to identify classes of materials that might be in the Hanford high-level waste tanks and that could accelerate or reduce the starting temperature of the reaction(s) of concern. We plan to use the resulted of this study to determine which materials or class of materials merit additional research.
Date: May 1, 1992
Creator: Scheele, R.D.; Bryan, S.A.; Johnston, J.W.; Tingey, J.M.; Burger, L.L. & Hallen, R.T.
Partner: UNT Libraries Government Documents Department

Analysis of sludge from Hanford K East Basin canisters

Description: Sludge samples from the canisters in the Hanford K East Basin fuel storage pool have been retrieved and analyzed. Both chemical and physical properties have been determined. The results are to be used to determine the disposition of the bulk of the sludge and to assess the impact of residual sludge on dry storage of the associated intact metallic uranium fuel elements. This report is a summary and review of the data provided by various laboratories. Although raw chemistry data were originally reported on various bases (compositions for as-settled, centrifuged, or dry sludge) this report places all of the data on a common comparable basis. Data were evaluated for internal consistency and consistency with respect to the governing sample analysis plan. Conclusions applicable to sludge disposition and spent fuel storage are drawn where possible.
Date: September 12, 1997
Creator: Makenas, B.J.; Welsh, T.L.; Baker, R.B.; Hoppe, E.W.; Schmidt, A.J.; Abrefah, J. et al.
Partner: UNT Libraries Government Documents Department

Ferrocyanide safety project: Task 3. 5 cyanide species analytical methods development

Description: This report summarizes the results of studies conducted in FY 1992 to develop methods for the identification and quantification of cyanide species in ferrocyanide tank waste. Currently there are 24 high-level waste storage tanks at the Hanford Site that have been placed on a Ferrocyanide Tank Watchlist because they contain an estimated 1,000 g-moles or greater amount of precipitated ferrocyanide. This amount of ferrocyanide is of concern because the consequences of a potential explosion may exceed those reported previously in safety analyses. The threshold concentration of total cyanide within the tank waste matrix that is expected to be a safety concern is estimated at approximately 1 to 3 wt%. Methods for detection and speciation of ferrocyanide complexes in actual waste are needed to definitively measure and quantitate the amount of ferrocyanides present within actual waste tanks to a lower limit of at least 0.1 wt% in order to bound the safety concern.
Date: January 1, 1993
Creator: Bryan, S.A.; Pool, K.H.; Burger, L.L.; Carlson, C.D.; Hess, N.J.; Matheson, J.D. et al.
Partner: UNT Libraries Government Documents Department

An assessment of the dilution required to mitigate Hanford tank 241-SY-101

Description: A group of experts from PNL and WHC convened November 2 and 3, 1994, to screen the current state of knowledge about dilution and reach a consensus on the minimum dilution ratio that will achieve passive mitigation of Tank 241-SY-101 wastes and the dilution ratio that would satisfy the given cross-site transfer criteria with reasonable assurance. The panel evaluated the effects of dilution on the parameters important in gas generation, retention, and release and reached the following conclusions, which are deduced from the existing body of data, experience, and analyses: (1) Dissolution of solids is the single most important aspect of mitigation by dilution. We are confident that diluting until nitrates, nitrites, and aluminum salts are dissolved will mitigate Hanford flammable gas tanks; (2) Sufficient solids dissolution can be achieved in Tank 241-SY-101 at a dilution ratio of 1:1, which will result in a average specific gravity of approximately 1.35. It is likely that a 0.5:1 dilution will also mitigate 241-SY-101, but the current uncertainty is too high to recommend this dilution ratio; (3) The recommended dilution requires a diluent with at least 2 molar free hydroxide, because aluminum probably precipitates at lower hydroxide concentrations. The transfer criteria for Tank 241-SY-101 waste were also evaluated. These criteria have been specified as solids content {<=}30% (volume), viscosity {<=}30% cP and density <1.5 g/mL. (1) Solids content is the limiting criterion if it is defined as volume fraction of settled solids. A 1:1 dilution will satisfy this criterion at nominal premixing conditions in Tank 241-SY-101; however, analysis of Window E core samples suggests that up to 1.5:1 might be required. If the solids content is interpreted simply as solids volume fraction no further dilution is necessary, because Tank 241-SY-101 waste (excluding the crust) is already below 30%; (2) Bulk density is the ...
Date: February 1, 1995
Creator: Hudson, J. D.; Bredt, P. R.; Felmy, A. R.; Stewart, C. W.; Tingey, J. M.; Trent, D. S. et al.
Partner: UNT Libraries Government Documents Department

Ferrocyanide safety project: Task 3.5 cyanide species analytical methods development. FY 1992 annual report

Description: This report summarizes the results of studies conducted in FY 1992 to develop methods for the identification and quantification of cyanide species in ferrocyanide tank waste. Currently there are 24 high-level waste storage tanks at the Hanford Site that have been placed on a Ferrocyanide Tank Watchlist because they contain an estimated 1,000 g-moles or greater amount of precipitated ferrocyanide. This amount of ferrocyanide is of concern because the consequences of a potential explosion may exceed those reported previously in safety analyses. The threshold concentration of total cyanide within the tank waste matrix that is expected to be a safety concern is estimated at approximately 1 to 3 wt%. Methods for detection and speciation of ferrocyanide complexes in actual waste are needed to definitively measure and quantitate the amount of ferrocyanides present within actual waste tanks to a lower limit of at least 0.1 wt% in order to bound the safety concern.
Date: January 1, 1993
Creator: Bryan, S. A.; Pool, K. H.; Burger, L. L.; Carlson, C. D.; Hess, N. J.; Matheson, J. D. et al.
Partner: UNT Libraries Government Documents Department

Waste Slurry Particle Properties for Use in Slurry Flow Modeling

Description: Hanford's tank farm piping system must be substantially modified to deliver high-level wastes from the underground storage tanks to the Waste Treatment Plant now under construction. Improved knowledge of the physical properties of the solids was required to support the design of the modified system. To provide this additional knowledge, particle size distributions for composite samples from seven high-level waste feed tanks were measured using two different laser lightscattering particle size analyzers. These measurements were made under a variety of instrumental conditions, including various flow rates through the sample loop, various stirring rates in the sample reservoir, and before and after subjecting the particles to ultrasonic energy. A mean value over all the tanks of 4.2 {micro}m was obtained for the volume-based median particle size. Additional particle size information was obtained from sieving tests, settling tests and microscopic observations.
Date: February 26, 2003
Creator: Jewett, J. R.; Conrads, T. J.; Julyk, L. J.; Reynolds, D. A.; Jensen, L.; Kirch, N. W. et al.
Partner: UNT Libraries Government Documents Department

Ferrocyanide-containing waste tanks: Ferrocyanide chemistry and reactivity

Description: The complexing constant for hexacyano-iron complexes, both Fe(2) and Fe(3), are exceptionally large. The derived transition metal salts or double salts containing alkali metal ions are only slightly soluble. The various nickel compounds examined in this study, i.e., those predicted to have been formed in the Hanford waste scavenging program, are typical examples. In spite of their relative stability towards most reagents under ambient conditions, they are all thermodynamically unstable towards oxidation and react explosively with oxidants such as nitrate or nitrate salts when heated to temperatures in excess of 200{degree}C. 42 refs., 5 figs., 3 tabs.
Date: September 1, 1991
Creator: Scheele, R.D.; Burger, L.L.; Tingey, J.M.; Bryan, S.A. (Pacific Northwest Lab., Richland, WA (United States)); Borsheim, G.L.; Simpson, B.C. et al.
Partner: UNT Libraries Government Documents Department