SULFATE SOLUBILITY LIMIT VERIFICATION FOR DWPF SLUDGE BATCH 7A

PDF Version Also Available for Download.

Description

During processing at the Defense Waste Processing Facility (DWPF), high sulfate concentrations in the feed are a concern to DWPF as it can lead to the formation of a detrimental, sulfate-rich, molten salt phase on the surface of the glass melt pool. To avoid these issues, a sulfate concentration limit was implemented into the Product Composition Control System (PCCS). Related to SB7a frit development efforts, the Savannah River National Laboratory (SRNL) assessed the viability of using the current 0.6 wt % SO{sub 4}{sup 2-} limit set for SB6 (in glass) and the possibility of increasing the SO{sub 4}{sup 2-} solubility ... continued below

Creation Information

Billings, A. April 19, 2011.

Context

This report is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this report can be viewed below.

Who

People and organizations associated with either the creation of this report or its content.

Author

Publisher

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this report. Follow the links below to find similar items on the Digital Library.

Description

During processing at the Defense Waste Processing Facility (DWPF), high sulfate concentrations in the feed are a concern to DWPF as it can lead to the formation of a detrimental, sulfate-rich, molten salt phase on the surface of the glass melt pool. To avoid these issues, a sulfate concentration limit was implemented into the Product Composition Control System (PCCS). Related to SB7a frit development efforts, the Savannah River National Laboratory (SRNL) assessed the viability of using the current 0.6 wt % SO{sub 4}{sup 2-} limit set for SB6 (in glass) and the possibility of increasing the SO{sub 4}{sup 2-} solubility limit in PCCS to account for anticipated sulfur concentrations, targeted waste loadings, and inclusion of secondary streams (e.g., Actinide Removal Process (ARP)) with two recommended frits (Frit 418 and Frit 702) for SB7a processing. For a nominal SB7a blend with a 63 inch SB6 heel remaining in Tank 40 (projection SB7a-63), a 0.60 wt% SO{sub 4}{sup 2-} in glass limit was determined for waste loadings of 34 wt% up to 40 wt% with Frit 418 based on crucible melts with batched chemicals. SRNL also examined the inclusion of ARP for the same blending scenario (SB7a-63-ARP) with Frit 418 and at least a 0.6 wt% SO{sub 4}{sup 2-} level, and waste loadings of 34 wt% to 40 wt% were also acceptable. When a visible yellow and/or white sulfate salt layer was visible on the surface of any cooled glass, it was assumed to have surpassed the solubility limit of SO{sub 4}{sup 2-} for that particular composition. All of the glasses fabricated at these concentrations did not exhibit a sulfate rich salt layer on the surface of the glass melt and retained the majority of the batched SO{sub 4}{sup 2-}. At higher levels of SO{sub 4}{sup 2-} 'spiked' into the projected sludge compositions over the aforementioned interval of waste loadings, with Frit 418, low viscosity sulfur layers were observed on the surface of glass melts which confirm exceeding the solubility limit. The same sludge scenarios were also tested with Frit 702 and all glasses did not exhibit sulfur layers on the surfaces of the glass melts at spiking levels up to 0.80 wt% SO{sub 4}{sup 2-}. An ultimate SO{sub 4}{sup 2-} limit was not defined with Frit 702, but if projected SO{sub 4}{sup 2-} concentrations are expected to increase with the onset of SB7a processing, a higher limit is achievable with Frit 702 than is achievable with Frit 418. Given the anticipated concentration of SO{sub 4}{sup 2-} for SB7a, a SO{sub 4}{sup 2-} limit of 0.6 wt % SO{sub 4}{sup 2-} is recommended for processing using Frit 418. Once the confirmed SB7a composition is known and should a higher limit be needed, SRNL can re-evaluate the limit based on the actual composition and provide an updated recommendation. It has been observed that higher levels of SO{sub 4}{sup 2-} in glass can be retained with compositional changes to the frit, as was demonstrated by the glasses fabricated using Frit 702. SRNL also recommends the continuation of studies to define a more 'global' sulfate concentration limit to account for future sludge batch composition uncertainties.

Notes

available

Language

Item Type

Identifier

Unique identifying numbers for this report in the Digital Library or other systems.

  • Report No.: SRNL-STI-2011-00197
  • Grant Number: DE-AC09-08SR22470
  • DOI: 10.2172/1014145 | External Link
  • Office of Scientific & Technical Information Report Number: 1014145
  • Archival Resource Key: ark:/67531/metadc840438

Collections

This report is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this report?

When

Dates and time periods associated with this report.

Creation Date

  • April 19, 2011

Added to The UNT Digital Library

  • May 19, 2016, 3:16 p.m.

Description Last Updated

  • Dec. 12, 2016, 6:41 p.m.

Usage Statistics

When was this report last used?

Yesterday: 0
Past 30 days: 0
Total Uses: 4

Interact With This Report

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

International Image Interoperability Framework

IIF Logo

We support the IIIF Presentation API

Billings, A. SULFATE SOLUBILITY LIMIT VERIFICATION FOR DWPF SLUDGE BATCH 7A, report, April 19, 2011; United States. (digital.library.unt.edu/ark:/67531/metadc840438/: accessed June 23, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.