Company Performed Work:
AEM Consulting, LLC
The scope of work required preparation of a preconceptual study of ion exchange systems for removal of cesium from tank waste supernate, using concepts potentially available from a commercial vendor, prior to transfer of treated LAW to the WTP LAW Vitrification Facility (by-passing the WTP Pretreatment Facility). This capability is being investigated to mitigate potential delays in the Pretreatment Facility startup and allow production of LAW glass for an interim time period. Expression of interest information obtained from vendors by WRPS resulted in selecting a non-elutable ion exchange material as a basis for the cesium ion exchange process to approximate a commercial system. The study was completed for WRPS to use as a basis for comparing a commercial system approach with an in-tank system proposed to provide a similar capability.
Two configuration alternatives are considered for the commercial system in this study. One configuration is based on a single pass ion exchange concept, where supernate is passed through the ion exchange system and treated LAW transferred to the vitrification facility feed tanks. The other configuration is based on recycling treated LAW from the ion exchange system back to the source DST. Supernate is recycled through the ion exchange system until the entire DST inventory complies with vitrification facility feed criteria. The DST treated supernate inventory is then used as a source for transfers to the vitrification facility feed tanks.
Properties of ion exchange material for a commercial system are assumed to be bounded by the properties of CST (high Cs loading material) and zeolite (low Cs loading material) for the purposes of completing this study.
The scope of work included preparation of a process description for each alternative considered, including:
- material balances to describe material flows;
- vessel sizing;
- sizing of facility structures required to house the process equipment;
- discussion of tank farm interfaces;
- comparison of alternatives; and
- identification of risk, safety, regulatory considerations, and technical maturity issues.
- Tasks include:
- Prepare a functional breakdown of the DF LAW concept, with associated requirements, to define the basis for selecting unit operations included in each alternative;
- Develop introductory material describing background for the DF LAW concept;
- Develop narrative of the integration of the DF LAW concept with the WTP;
- Prepare material balances for each alternative.
- Estimate facility hazard category and equipment dose rate;
- Develop a narrative description DF LAW facilities, systems, and process equipment, including a layout for each alternative;
- Include a narrative description of WTP supporting systems and interfaces;
- Develop tables and narrative summarizing risks identified during preparation of the DF LAW preconceptual engineering study.
- Document all calculations and required assumptions for each task
- Document conclusions.
April 2012 through September 2012