Removal of plutonium and uranium from process streams using ultrafiltration membranes

A series of experiments using hollow fiber ultrafiltration modules was run on various Mound Laboratory waste streams contaminated with 238Pu, 239Pu, and 233U. These modules had various molecular weight cut-offs ranging from 2000 to 80,000. The types of waste solution studied consisted of waste water from the ''hot'' laundry, decontamination water from the Plutonium Processing (PP) Building, and influent to the Waste Disposal (WD) Building. These experiments have shown that the ability to remove radioactivity is a function of the contents of the waste stream. This is due to the fact that the radioactivity in the waste water is in various forms (ionic, polymeric, colloidal, and adsorbed onto suspended solids). Removal of suspended or colloidal material was very high, while removal of ionic material was very low. The best case proved to be the laundry waste water which yielded a rejection of radioactivity up to 99.8%, with a product concentration of <0.1 dis/min/ml. The worst case was decontamination water which yielded a rejection of radioactivity of 85 to 88% with a product concentration of 166 to 229 dis/min/ml (initial feed was 1440 dis/min/ml). Typical WD influent showed a rejection of radioactivity of 90 to 98% and a product concentration of from 7 to 100 dis/min/ml, depending upon initial concentration and the nature of the waste stream