Pilot-scale tests of HEME and HEPA dissolution process

Technical Report · Wed Jun 01 04:00:00 EDT 1994

DOI:https://doi.org/10.2172/10186263· OSTI ID:10186263

Qureshi, Z H; Strege, D K

A series of pilot-scale demonstration tests for the dissolution of High Efficiency Mist Eliminators (HEME`s) and High Efficiency Particulate Airfilters (HEPA) were performed on a 1/5th linear scale. These fiberglass filters are to be used in the Defense Waste Processing Facility (DWPF) to decontaminate the effluents from the off-gases generated during the feed preparation process and vitrification. When removed, these filters will be dissolved in the Decontamination Waste Treatment Tank (DWTT) using 5 wt% NaOH solution. The contaminated fiberglass is converted to an aqueous stream which will be transferred to the waste tanks. The filter metal structure will be rinsed with process water before its disposal as low-level solid waste. The pilot-scale study reported here successfully demonstrated a simple one step process using 5 wt% NaOH solution. The proposed process requires the installation of a new water spray ring with 30 nozzles. In addition to the reduced waste generated, the total process time is reduced to 48 hours only (66% saving in time). The pilot-scale tests clearly demonstrated that the dissolution process of HEMEs has two stages - chemical digestion of the filter and mechanical erosion of the digested filter. The digestion is achieved by a boiling 5 wt% caustic solutions, whereas the mechanical break down of the digested filter is successfully achieved by spraying process water on the digested filter. An alternate method of breaking down the digested filter by increased air sparging of the solution was found to be marginally successful are best. The pilot-scale tests also demonstrated that the products of dissolution are easily pumpable by a centrifugal pump.

• Research Organization: Westinghouse Savannah River Co., Aiken, SC (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC09-89SR18035
• OSTI ID: 10186263
• Report Number(s): WSRC-TR--94-0306; ON: DE95000758
• Country of Publication: United States
• Language: English

Related Subjects

052001
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
COMPILED DATA
DECONTAMINATION
DEMONSTRATION PROGRAMS
DISSOLUTION
FILTERS
MIST EXTRACTORS
PERFORMANCE TESTING
RADIOACTIVE EFFLUENTS
RADIOACTIVE WASTE FACILITIES
RADIOACTIVE WASTE PROCESSING
SAVANNAH RIVER PLANT
WASTE PROCESSING