B222 A Comprehensive Approach to Reducing Radioactive Material Release in BWR Containment Venting

Abstract

A comprehensive approach to reducing radioactive material release was developed for BWR filtered containment venting. Aerosol filter equipment was developed with decontamination factor of 1000. This equipment consists of scrubber and metal fiber filters. Its performance was demonstrated by tests using TiO_2 and other aerosol particles. While aerosol filter is effective for reducing environmental release of radioactive cesium, other measures were developed to reduce iodine release. This includes pH control of water within the primary containment vessel and iodine filters with silver zeolite. The NaOH spray system keeps the pH over 7 during a severe accident and reduces generation of organic iodine. The iodine filter captures gaseous radioactive iodine including organic iodine.