SCAVENGING OF PARTICULATE MATTER IN CONNECTION WITH NUCLEAR-POWERED SHIPS. Final Scientific Report

The work carried out over a 2 1/2-yr period on the scavenging of radioactive particles which might be released by the reactor system of a nuclear- powered ship is summarized. Two types of dispersions were considered: aerosols and hydrosols. Radioactive aerosols were scavenged by heterogeneous coagulation with solid and liquid aerosols produced within the radioactive aerosol cloud. Liquid or highly hygroscopic particles, which can be classified as solid particles with liquld films on their surfaces, were found to be the most effective scavengers. A system of fine water spray and hydrolysis products of silicon tetrafluoride was found to be suitable for field application. Scavenging of radioactive cations, anions, and colloids of corrosion and fission products was studied in substitute ocean water, natural ocean water, and natural harbor water. A scavenging system composed of KMnO/sub 4/ and ferrous salts successfully removed most of the radioisotopes. Fe(OH)/sub 3/--MnO/sub 2/ hydrate adsorbed and absorbed radioactive species, thus transferring them from a liquid to a solid phase. Addition of Floc 111 to the system improved sedimentation. The KMnO/sub 4/-FeSO/sub 4/-Floc 111 system was found to bs suitable for field application. (auth