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

Pareizs, J. M.; Newell, D. D.; Martino, C. J.; Crawford, Charles L.; Johnson, F. C.

doi:10.2172/1330956

“…The SRAT and SME product slurry densities are 1.23 and 1.43 mg/L, respectively, which are consistent with the overall solids content attained. The SC-18 SRAT product density of 1.23 g/mL is higher than the SB9 nitric-formic qualification SRAT product density of 1.15 mg/L [24]. The SC-18 SRAT and SME product supernatant densities of 1.09 g/mL and 1.13 g/mL, respectively, are equivalent to the supernate densities measured for the SRAT and SME products of the SB9 nitric-formic qualification [24].…”

Section: Srat and Sme Product Analysesmentioning

confidence: 68%

“…The SC-18 SRAT product density of 1.23 g/mL is higher than the SB9 nitric-formic qualification SRAT product density of 1.15 mg/L [24]. The SC-18 SRAT and SME product supernatant densities of 1.09 g/mL and 1.13 g/mL, respectively, are equivalent to the supernate densities measured for the SRAT and SME products of the SB9 nitric-formic qualification [24]. Concentrations of the elemental constituents in the SRAT and SME product slurries are given in Table 3-30 and Table 3-31, respectively, with results greater than 0.1 wt% shaded for easy identification.…”

Section: Srat and Sme Product Analysesmentioning

confidence: 71%

“…In an effort to prevent, or minimize, a carryover event, an antifoaming agent is added. The amount of antifoam added for the SC-18 demonstration was scaled based on a 6000 gallon DWPF SRAT receipt (Table 3- 24). However, approximately one tenth of the targeted amount of antifoam was added in the SRAT: ~0.077g of antifoam (0.15 gallon DWPF equivalent) and ~0.052g of antifoam (0.10 gallon DWPF equivalent).…”

Section: Rheologymentioning

confidence: 99%

See 1 more Smart Citation

Actual Waste Demonstration of the Nitric-Glycolic Flowsheet for Sludge Batch 9 Qualification

D.¹,

Pareizs

²

,

Martino

³

et al. 2016

0

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For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs qualification testing to demonstrate that the sludge batch is processable. Testing performed by the Savannah River National Laboratory has shown glycolic acid to be effective in replacing the function of formic acid in the DWPF chemical process. The nitric-glycolic flowsheet reduces mercury, significantly lowers the catalytic generation of hydrogen and ammonia which could allow purge reduction in the Sludge Receipt and Adjustment Tank (SRAT), stabilizes the pH and chemistry in the SRAT and the Slurry Mix Evaporator (SME), allows for effective rheology adjustment, and is favorable with respect to melter flammability. In order to implement the new flowsheet, SRAT and SME cycles, designated SC-18, were performed using a Sludge Batch (SB) 9 slurry blended from SB8 Tank 40H and Tank 51H samples. The SRAT cycle involved adding nitric and glycolic acids to the sludge, refluxing to steam strip mercury, and dewatering to a targeted solids concentration. Data collected during the SRAT cycle included offgas analyses, process temperatures, heat transfer, and pH measurements. The SME cycle demonstrated the addition of glass frit and the replication of six canister decontamination additions. The demonstration concluded with dewatering to a targeted solids concentration. Data collected during the SME cycle included offgas analyses, process temperatures, heat transfer, and pH measurements. Slurry and condensate samples were collected for subsequent analysis. Chemical Process Cell (CPC) demonstrations utilizing the alternate reductant flowsheet were performed at an acid stoichiometry of 78.0% Koopman Minimum Acid basis (87.1% Hsu basis) for the SRAT cycle. The scope specified by the technical task request has been successfully completed. Highlights of the testing results are summarized in the paragraphs below. The total solids measurements of the SRAT and SME products were 24.6 and 49.0 weight percent (wt%), respectively, which matched the targets of 25 wt% and 48 wt% acceptably. The consistency and yield stress of the SRAT receipt material fall within the DWPF design basis. The SRAT product yield stress and consistency (0 Pa and 2.8 cP, respectively) are below the DWPF design basis. The SME product yield stress and consistency were 1.0 Pa and 16.0 cP, respectively. The SME product yield stress is below the DWPF design basis. It should be noted that similar rheological properties were encountered during SB5 processing at DWPF. DWPF successfully processed SB5 by implementing process control software to mitigate issues related to the melter feed. This software is still in use at DWPF. Based on the comparison of the iron in the SRAT product and SME product analyses, the waste loading of the SME product is 37.6%. The current DWPF target for waste loading is 36%. Calculations based on several of the other major sludge components (Al, Ca, Mn, Ni, and U) indicated waste loadings ranging from 36....

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“… Hydrogen generation  Nitrogen oxide generation  Anion conversions  Hg recovery/removal Data from SB7, SB7b, SB8, and SB9 simulant 3,6 and real-waste 7,8 testing have been reviewed and reanalyzed to identify any effects of ruthenium source selection on processing under the nitric-formic flowsheet. Due to processing complications during testing and a lack of existing data, only SB8 and SB9 testing data was employed when considering offgas generation.…”

Section: List Of Figuresmentioning

confidence: 99%

Recommendation of ruthenium source for sludge batch flowsheet studies

Woodham¹

2017

0

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Included herein is a preliminary analysis of previously-generated data from sludge batches 7a, 7b, 8, and 9 sludge simulant and real-waste testing, performed to recommend a form of ruthenium for future sludge batch simulant testing under the nitric-formic flowsheet. Focus is given to reactions present in the Sludge Receipt and Adjustment Tank cycle, given that this cycle historically produces the most changes in chemical composition during Chemical Process Cell processing. Data is presented and analyzed for several runs performed under the nitric-formic flowsheet, with consideration given to effects on the production of hydrogen gas, nitrous oxide gas, consumption of formate, conversion of nitrite to nitrate, and the removal and recovery of mercury during processing. Additionally, a brief discussion is given to the effect of ruthenium source selection under the nitric-glycolic flowsheet. An analysis of data generated from scaled demonstration testing, sludge batch 9 qualification testing, and antifoam degradation testing under the nitric-glycolic flowsheet is presented. Experimental parameters of interest under the nitric-glycolic flowsheet include N 2 O production, glycolate destruction, conversion of glycolate to formate and oxalate, and the conversion of nitrite to nitrate. To date, the number of real-waste experiments that have been performed under the nitric-glycolic flowsheet is insufficient to provide a complete understanding of the effects of ruthenium source selection in simulant experiments with regard to fidelity to real-waste testing. Therefore, a determination of comparability between the two ruthenium sources as employed under the nitric-glycolic flowsheet is made based on available data in order to inform ruthenium source selection for future testing under the nitric-glycolic flowsheet.

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“…24 presents the DWPF to SRNL scale factor and targeted processing parameters for the SRAT and SME cycles. The scale factor is based on a DWPF SRAT receipt volume of 6000 gallons.…”

mentioning

confidence: 99%

Actual waste demonstration of the nitric-glycolic flowsheet for sludge batch 9 qualification

Newell

¹

,

Pareizs

²

,

Martino

³

et al. 2017

Self Cite

View full text Add to dashboard Cite

For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs qualification testing to demonstrate that the sludge batch is processable. Testing performed by the Savannah River National Laboratory has shown glycolic acid to be effective in replacing the function of formic acid in the DWPF chemical process. The nitric-glycolic flowsheet reduces mercury, significantly lowers the catalytic generation of hydrogen and ammonia which could allow purge reduction in the Sludge Receipt and Adjustment Tank (SRAT), stabilizes the pH and chemistry in the SRAT and the Slurry Mix Evaporator (SME), allows for effective rheology adjustment, and is favorable with respect to melter flammability. In order to implement the new flowsheet, SRAT and SME cycles, designated SC-18, were performed using a Sludge Batch (SB) 9 slurry blended from SB8 Tank 40H and Tank 51H samples. The SRAT cycle involved adding nitric and glycolic acids to the sludge, refluxing to steam strip mercury, and dewatering to a targeted solids concentration. Data collected during the SRAT cycle included offgas analyses, process temperatures, heat transfer, and pH measurements. The SME cycle demonstrated the addition of glass frit and the replication of six canister decontamination additions. The demonstration concluded with dewatering to a targeted solids concentration. Data collected during the SME cycle included offgas analyses, process temperatures, heat transfer, and pH measurements. Slurry and condensate samples were collected for subsequent analysis. Chemical Process Cell (CPC) demonstrations utilizing the alternate reductant flowsheet were performed at an acid stoichiometry of 78.0% Koopman Minimum Acid basis (87.1% Hsu basis) for the SRAT cycle. The scope specified by the technical task request has been successfully completed. Highlights of the testing results are summarized in the paragraphs below. The total solids measurements of the SRAT and SME products were 24.6 and 49.0 weight percent (wt%), respectively, which matched the targets of 25 wt% and 48 wt% acceptably. The consistency and yield stress of the SRAT receipt material fall within the DWPF design basis. The SRAT product yield stress and consistency (0 Pa and 2.8 cP, respectively) are below the DWPF design basis. The SME product yield stress and consistency were 1.0 Pa and 16.0 cP, respectively. The SME product yield stress is below the DWPF design basis. It should be noted that similar rheological properties were encountered during SB5 processing at DWPF. DWPF successfully processed SB5 by implementing process control software to mitigate issues related to the melter feed. This software is still in use at DWPF. Based on the comparison of the iron in the SRAT product and SME product analyses, the waste loading of the SME product is 37.6%. The current DWPF target for waste loading is 36%. Calculations based on several of the other major sludge components (Al, Ca, Mn, Ni, and U) indicated waste loadings ranging from 36....

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

Cited by 7 publications

References 12 publications

Actual Waste Demonstration of the Nitric-Glycolic Flowsheet for Sludge Batch 9 Qualification

Actual Waste Demonstration of the Nitric-Glycolic Flowsheet for Sludge Batch 9 Qualification

Recommendation of ruthenium source for sludge batch flowsheet studies

Actual waste demonstration of the nitric-glycolic flowsheet for sludge batch 9 qualification

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