Sludge Washing and Demonstration of the DWPF Flowsheet in the SRNL Shielded Cells for Sludge Batch 5 Qualification

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

doi:10.2172/943577

Cited by 10 publications

(11 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The finished product was applied to DWPF vessels where The initial work focused on using the data collected during qualification of Sludge Batch 3 and Sludge Batch 5 to develop and benchmark the model. 4,5 The model replicated a small-scale test apparatus, and used known slurry properties, and operating parameters of the SRAT and SME that were employed during the qualification testing. The model results predicted the hydrogen release rate from the vessel upon start of agitation, which were then compared to the experimental data.…”

Section: Development Of Model To Predict Hydrogen Release From Dwpf Vesselsmentioning

confidence: 99%

“…The tank dimensions and slurry properties are taken from SRNL technical reports or DWPF design documents and are described in this report. 4,5,7 The solid-liquid slurry is modeled as a single phase Bingham plastic fluid with yield stress and consistency selected to match the rheological properties of the slurry from sludge batch qualification testing or the DWPF vessel. This approach will not include the interparticle forces that exist between the sludge particles, but it will enable modeling of the mixing cavern and fluid motion that exists in these impeller-mixed vessels.…”

Section: Development Of Model To Predict Hydrogen Release From Dwpf Vesselsmentioning

confidence: 99%

See 1 more Smart Citation

Modeling DWPF Hydrogen Gas Retention and Release

Poirier

2021

View full text Add to dashboard Cite

SRNL-STI-2020-00279Revision 0 vii effort was deferred. Additional work is recommended to develop a model whose single-phase non-Newtonian properties results from interparticle and inter-phase forces, which would be more representative of the quiescent and mixing conditions in the DWPF. This model would use interparticle forces to create the yield stress in the sludge. The model would also include bubble coalescence to simulate bubble growth during the quiescent period. At this time, the M-Star® model assumes that gas bubbles are released when they reach the slurryhead space interface. Efforts should be pursued to include the physics of gas release at this interface in the model. Perform additional work to understand the effect of slurry consistency on the hydrogen gas release rate.The M-Star software has not been verified for Safety Class purposes. An approach was identified to upgrade the software from level D to level B.Other DOE Sites, such as Los Alamos and Hanford, have used CFD to assist in designing processes. An effort should be made to obtain information on the QA level of their software, and if classified as Safety Class or Safety Significant, determine how they achieved that classification.

show abstract

Section: Development Of Model To Predict Hydrogen Release From Dwpf Vesselsmentioning

confidence: 99%

Section: Development Of Model To Predict Hydrogen Release From Dwpf Vesselsmentioning

confidence: 99%

Modeling DWPF Hydrogen Gas Retention and Release

Poirier

2021

View full text Add to dashboard Cite

show abstract

“…In some of the SRNL tests for waste feed qualification of a sludge batch, hydrogen release was observed as the SRAT/SME demonstration testing started. 49,50,46 This measured hydrogen is believed to be retained hydrogen released upon the start of agitation and heating of the SRAT feed material. The release is believed to represent a release upon the start of mixing, but the head space volume and time to reach the detector spread the peak over a period of time, which complicates determining the exact timing of the release and determination of the release rate.…”

Section: Sludge Batch Qualificationmentioning

confidence: 99%

Retained Hydrogen Literature Study for DWPF

Hansen

2019

View full text Add to dashboard Cite

SRNL-STI-2019-00394 Revision 0 vi volume, purge rate, and power input, this data cannot be directly applied to the DWPF, but it is important to note that hydrogen is released over a finite time, rather than instantaneously. Previous work by SRNL and PNNL has measured the rheology of Hanford sludge, and shown the rheology (i.e., yield stress or shear strength) to increase as the sludge is allowed to settle. Changes in sludge rheology need to be considered when assessing changes to the DWPF retained hydrogen program. A comparison of buoyancy and inertial forces under SRAT operating conditions (1-10 Pa yield stress, 1.38 g/mL density, 65 or 130 rpm, 9,000 gallons of feed) on the bubbles (approximated as 300 micron diameter) found the inertial forces to be more than 350,000 times larger than the buoyancy forces. With this ratio of forces, the gas bubbles generated will follow the fluid motion in the SRAT, and only release when they reach the slurry-vapor interface. An informal Lattice Boltzmann Computation Fluid Dynamics calculation was performed on a SRAT type vessel. The liquid was assumed to have a density of 1 g/mL and a viscosity of 20 cP. In the simulation, approximately 50% of the bubbles were released to the vapor space over ~80 seconds. The simulation showed the bubbles to follow the liquid flow, and only release when they reached the liquid surface.

show abstract

“…Table 4 along with the reported values for the SC-6 (SB-5) and SC-9 (SB-6) SRAT receipt sample from the Shielded Cells qualification runs for comparison. 3,8 SB6-24 was trimmed for mercury and noble metals assuming that the ARP solids were 50% MST and 50% SB6-G entrained sludge. This resulted in concentrations in the SB6-24 total solids that were 89.1 % those of SB6-G. Tank 40 as processed (blended with the SB4 heel) actually had lower noble metal concentrations than the SC-6 qualification sample from Tank 51.…”

Section: Simulant Preparation and Characterizationmentioning

confidence: 99%

Sludge Batch 6/Tank 40 Simulant Chemical Process Cell Simulations

Koopman¹

2010

View full text Add to dashboard Cite

Sludge Washing and Demonstration of the DWPF Flowsheet in the SRNL Shielded Cells for Sludge Batch 5 Qualification

Cited by 10 publications

References 4 publications

Modeling DWPF Hydrogen Gas Retention and Release

Modeling DWPF Hydrogen Gas Retention and Release

Retained Hydrogen Literature Study for DWPF

Sludge Batch 6/Tank 40 Simulant Chemical Process Cell Simulations

Contact Info

Product

Resources

About