IMPACT OF NOBLE METALS AND MERCURY ON HYDROGEN GENERATION DURING HIGH LEVEL WASTE PRETREATMENT AT THE SAVANNAH RIVER SITE

Stone, M; Tommy Edwards, T; David Koopman, D

Title: IMPACT OF NOBLE METALS AND MERCURY ON HYDROGEN GENERATION DURING HIGH LEVEL WASTE PRETREATMENT AT THE SAVANNAH RIVER SITE

Full Record
Other Related Research

Abstract

The Defense Waste Processing Facility (DWPF) at the Savannah River Site vitrifies radioactive High Level Waste (HLW) for repository internment. The process consists of three major steps: waste pretreatment, vitrification, and canister decontamination/sealing. HLW consists of insoluble metal hydroxides (primarily iron, aluminum, calcium, magnesium, manganese, and uranium) and soluble sodium salts (carbonate, hydroxide, nitrite, nitrate, and sulfate). The pretreatment process in the Chemical Processing Cell (CPC) consists of two process tanks, the Sludge Receipt and Adjustment Tank (SRAT) and the Slurry Mix Evaporator (SME) as well as a melter feed tank. During SRAT processing, nitric and formic acids are added to the sludge to lower pH, destroy nitrite and carbonate ions, and reduce mercury and manganese. During the SME cycle, glass formers are added, and the batch is concentrated to the final solids target prior to vitrification. During these processes, hydrogen can be produced by catalytic decomposition of excess formic acid. The waste contains silver, palladium, rhodium, ruthenium, and mercury, but silver and palladium have been shown to be insignificant factors in catalytic hydrogen generation during the DWPF process. A full factorial experimental design was developed to ensure that the existence of statistically significant two-way interactions could be determined withoutmore »« less

Authors:: Stone, M; Tommy Edwards, T; David Koopman, D

Publication Date:: Tue Mar 03 00:00:00 EST 2009

Research Org.:: Savannah River Site (SRS), Aiken, SC (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 949873

Report Number(s):: SRNL-STI-2008-00501
TRN: US200909%%517

DOE Contract Number:: DE-AC09-08SR22470

Resource Type:: Conference

Resource Relation:: Conference: AIChE Spring Meeting

Country of Publication:: United States

Language:: English

Subject:: 08 HYDROGEN; ALUMINIUM; CARBONATES; CONTAINERS; FORMIC ACID; HYDROGEN; HYDROXIDES; MANGANESE; MERCURY; PALLADIUM; RHODIUM; RUTHENIUM; URANIUM; WASTE PROCESSING; WASTES

Citation Formats


                    Stone, M, Tommy Edwards, T, and David Koopman, D. IMPACT OF NOBLE METALS AND MERCURY ON HYDROGEN GENERATION DURING HIGH LEVEL WASTE PRETREATMENT AT THE SAVANNAH RIVER SITE.  United States: N. p., 2009. 
        Web.

Copy to clipboard


                    Stone, M, Tommy Edwards, T, & David Koopman, D. IMPACT OF NOBLE METALS AND MERCURY ON HYDROGEN GENERATION DURING HIGH LEVEL WASTE PRETREATMENT AT THE SAVANNAH RIVER SITE.  United States.

Copy to clipboard


                    Stone, M, Tommy Edwards, T, and David Koopman, D. 2009.  
        "IMPACT OF NOBLE METALS AND MERCURY ON HYDROGEN GENERATION DURING HIGH LEVEL WASTE PRETREATMENT AT THE SAVANNAH RIVER SITE".  United States.  https://www.osti.gov/servlets/purl/949873.

Copy to clipboard


                    
@article{osti_949873,

  title        = {IMPACT OF NOBLE METALS AND MERCURY ON HYDROGEN GENERATION DURING HIGH LEVEL WASTE PRETREATMENT AT THE SAVANNAH RIVER SITE},

  author       = {Stone, M and Tommy Edwards, T and David Koopman, D},

  abstractNote = {The Defense Waste Processing Facility (DWPF) at the Savannah River Site vitrifies radioactive High Level Waste (HLW) for repository internment. The process consists of three major steps: waste pretreatment, vitrification, and canister decontamination/sealing. HLW consists of insoluble metal hydroxides (primarily iron, aluminum, calcium, magnesium, manganese, and uranium) and soluble sodium salts (carbonate, hydroxide, nitrite, nitrate, and sulfate). The pretreatment process in the Chemical Processing Cell (CPC) consists of two process tanks, the Sludge Receipt and Adjustment Tank (SRAT) and the Slurry Mix Evaporator (SME) as well as a melter feed tank. During SRAT processing, nitric and formic acids are added to the sludge to lower pH, destroy nitrite and carbonate ions, and reduce mercury and manganese. During the SME cycle, glass formers are added, and the batch is concentrated to the final solids target prior to vitrification. During these processes, hydrogen can be produced by catalytic decomposition of excess formic acid. The waste contains silver, palladium, rhodium, ruthenium, and mercury, but silver and palladium have been shown to be insignificant factors in catalytic hydrogen generation during the DWPF process. A full factorial experimental design was developed to ensure that the existence of statistically significant two-way interactions could be determined without confounding of the main effects with the two-way interaction effects. Rh ranged from 0.0026-0.013% and Ru ranged from 0.010-0.050% in the dried sludge solids, while initial Hg ranged from 0.5-2.5 wt%, as shown in Table 1. The nominal matrix design consisted of twelve SRAT cycles. Testing included: a three factor (Rh, Ru, and Hg) study at two levels per factor (eight runs), three duplicate midpoint runs, and one additional replicate run to assess reproducibility away from the midpoint. Midpoint testing was used to identify potential quadratic effects from the three factors. A single sludge simulant was used for all tests and was spiked with the required amount of noble metals immediately prior to performing the test. Acid addition was kept effectively constant except to compensate for variations in the starting mercury concentration. SME cycles were also performed during six of the tests.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/949873},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Mar 03 00:00:00 EST 2009},

  month        = {Tue Mar 03 00:00:00 EST 2009}

}

Copy to clipboard

Conference:

View Conference

Other availability

Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share:

Export Metadata

Save to My Library

Similar records in OSTI.GOV collections:

DWPF CATALYTIC HYDROGEN GENERATION PROGRAM - REVIEW OF CURRENT STATUS

Technical Report Koopman, D

Significant progress has been made in the past two years in improving the understanding of acid consumption and catalytic hydrogen generation during the Defense Waste Processing Facility (DWPF) processing of waste sludges in the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME). This report reviews issues listed in prior internal reviews, describes progress with respect to the recommendations made by the December 2006 external review panel, and presents a summary of the current understanding of catalytic hydrogen generation in the DWPF Chemical Process Cell (CPC). Noble metals, such as Pd, Rh, and Ru, are historically known catalystsmore »« less
https://doi.org/10.2172/962425

Full Text Available
CATALYTIC INTERACTIONS OF RHODIUM, RUTHENIUM, AND MERCURY DURING SIMULATED DWPF CPC PROCESSING WITH HYDROGEN GENERATION

Technical Report Koopman, D

Simulations of the Defense Waste Processing Facility (DWPF) Chemical Processing Cell (CPC) vessels were performed as part of the ongoing investigation into catalytic hydrogen generation. Rhodium, ruthenium, and mercury have been identified as the principal elemental factors affecting the peak hydrogen generation rate in the DWPF Sludge Receipt and Adjustment Tank (SRAT) for a given acid addition. The primary goal of this study is to identify any significant interactions between the three factors. Noble metal concentrations were similar to recent sludge batches. Rh ranged from 0.0026-0.013% and Ru ranged from 0.010-0.050% in the dried sludge solids, while initial Hg rangedmore »« less
https://doi.org/10.2172/940023

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

Technical Report Pareizs, J; Pickenheim, B; Bannochie, C; ...

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 51more »« less
https://doi.org/10.2172/991628

Full Text Available
INITIAL CHARACTERIZATIONS AND SRAT SIMULATIONS OF FOUR SLUDGE MATRIX STUDY SIMULANTS

Technical Report Koopman, D; Lambert, D

The Savannah River National Laboratory (SRNL) initiated a sludge matrix study to evaluate the impact of changing insoluble solid composition on the processing characteristics of slurries in the Defense Waste Processing Facility (DWPF). Three compositional ranges were developed for three groups of elements in the waste. The first was high iron/low aluminum versus low iron/high aluminum. The second was high calcium-manganese/low nickel, chromium, and magnesium versus low calcium-manganese/high nickel, chromium, and magnesium. The third was high noble metals (Ag, Pd, Rh, Ru) versus low noble metals. These three options can be combined to form eight distinct sludge compositions. The sludgemore »« less
https://doi.org/10.2172/969296

Full Text Available
DWPF SIMULANT CPC STUDIES FOR SB7B

Technical Report Koopman, D

Lab-scale DWPF simulations of Sludge Batch 7b (SB7b) processing were performed. Testing was performed at the Savannah River National Laboratory - Aiken County Technology Laboratory (SRNL-ACTL). The primary goal of the simulations was to define a likely operating window for acid stoichiometry for the DWPF Sludge Receipt and Adjustment Tank (SRAT). In addition, the testing established conditions for the SRNL Shielded Cells qualification simulation of SB7b-Tank 40 blend, supported validation of the current glass redox model, and validated the coupled process flowsheet at the nominal acid stoichiometry. An acid window of 105-140% by the Koopman minimum acid (KMA) equation (107-142%more »« less
https://doi.org/10.2172/1029388

Full Text Available

Similar Records