Performance of the ACWA Pilot Immobilized Cell Bioreactor in Degradation of HD and Tetrytol Payloads of the M60 Chemical Round

摘要

In 1996, public laws 104-208, 105-261, and 106-79 established and expanded the Assembled Chemical Weapons Assessment (ACWA) Program. To address public concerns over the safe destruction of the U.S. chemical weapon stockpile; the ACWA program was tasked to identify two or more viable alternative technologies to the baseline destruction method of incineration. Neutralization followed by biodegradation was one technology identified as having potential. Guelta and DeFrank conducted preliminary laboratory studies using 1-liter Immobilized Cell Bioreactors (ICB) to degrade hydrolyzed agents. These studies demonstrated the effectiveness of the ICB system to degrade hydrolyzed HD agent feed. In two follow-on studies, each conducted at Edgewood Chemical and Biological Command (ECBC), Edgewood MD, a scaled-up 1000-gallon pilot ICB system was operated for three and four months respectively. Over the course of these tests the ICB system degraded 61,274 lbs of 3.8% HD hydrolysis created from the HD stockpile stored at APG. Also degraded was approximately 2320 lbs of hydrolyzed tetrytol produced at the Pantex plant, Amarillo, TX. The neutralization/biodegradation process achieved a 99.9999% overall destruction removal efficiency (DRE) for HD agent, Tetrytol and schedule-2 compounds. This paper describes the ICB system and overall process employed for the ACWA Demonstration/Engineering Design Studies.