Division of Waste Management, Production, and Reprocessing programs progress report for January--June 1977

• Main Author: Lerch, R.E.
• Language: unknown
• Published: 2021
• Subjects: 12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; RADIOACTIVE WASTE PROCESSING; DIGESTION; LIQUID WASTES; RESEARCH PROGRAMS; SOLID WASTES; SOLIDIFICATION; BITUMENS; CEMENTS; CESIUM; FORMALDEHYDE; LEACHING; RADIOACTIVE WASTES; STRONTIUM; URANYL NITRATES; UREA; ACTINIDE COMPOUNDS; ALDEHYDES; ALKALI METALS; ALKALINE EARTH METALS; AMIDES; BUILDING MATERIALS; CARBONIC ACID DERIVATIVES; DISSOLUTION; ELEMENTS; MANAGEMENT; MATERIALS; METALS; NITRATES; NITROGEN COMPOUNDS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; OTHER ORGANIC COMPOUNDS; OXYGEN COMPOUNDS; PHASE TRANSFORMATIONS; PROCESSING; RADIOACTIVE MATERIALS; SEPARATION PROCESSES; TAR; URANIUM COMPOUNDS; URANYL COMPOUNDS; WASTE MANAGEMENT; WASTE PROCESSING; WASTES; Carbonic acid
• Online Access: http://www.osti.gov/servlets/purl/7085599; https://www.osti.gov/biblio/7085599; https://doi.org/10.2172/7085599

Construction of the 100-kg/day Radioactive Acid Digestion Test Unit (RADTU) facility was completed in June 1977 with the exception of the acid recycle mode, which is being added to the originally planned unit. Engineering tests of the acid recycle flowsheet, using test equipment one-quarter scale of the proposed acid recycle addition to RADTU, confirmed the validity of the zero effluent flowsheet proposed for RADTU. Studies were continued on immobilization of wastes in cement. Cement products containing up to 16 wt percent boric acid were successfully made and tested for compressive strength. The thermal characteristics of various waste products were determined using a differential scanning calorimeter. The ignition temperatures for bitumen and bitumen products containing salts, including sodium nitrate, were found to be about 400/sup 0/C. There was no significant lowering of the ignition temperature below that of bitumen itself upon incorporation of these salts into bitumen. Urea-formaldehyde products exhibited ignition temperatures around 300/sup 0/C. Ignition temperatures of resins (anion and cation) were relatively high (400 to 600/sup 0/C) except for anion exchange resin in the nitrate form which ignited about 250/sup 0/C. Leach tests were performed on various waste products immobilized in cement, urea-formaldehyde, and bitumen. The results indicated that cement solids exhibited the lowest leach rates for leaching of uranyl nitrate from immobilized anion exchange resin and from immobilized acid digestion residue. Leach rates of cesium and strontium from immobilized anion exchange resin were lowest for bitumen products. Work is proceeding on development of a process to reduce the volume of mercuric nitrate - nitric acid off-gas scrub solution without loss of the iodine. Preliminary results are promising and indicate that volume reductions of at least 10-fold can be achieved with as little as 0.01 percent of the iodine being volatilized.