A COMPACT, EFFICIENT PYROLYSIS/OXIDATION SYSTEM FOR SOLID WASTE

This paper addresses the feasibility of integrating pyrolysis, tar cracking and oxidation steps into a compact, efficient system for processing of spacecraft solid wastes. This work demonstrated that it is feasible to pyrolyze a representative spacecraft solid waste sample and crack and/or oxidize the effluent gases using in a microwave assisted, close-coupled integrated reactor system. The net result is a significant reduction (estimated at 70% lower) in the total energy requirement (per gram of sample) when compared to conventional heating and a simpler, more compact apparatus. Although a formal ESM calculation was not done for the preliminary reactor system due to its small size, by analogy to literature studies comparing microwave heating to conventional heating, a significant reduction in ESM is also expected for a full scale prototype. The need for waste processing varies greatly depending on the mission scenario. Another goal of the project was to demonstrate that a Microwave-Assisted Pyrolysis (MAP) approach can meet the short term, intermediate term, and long term objectives of NASA for closed-loop life support. Microwave-Assisted Pyrolysis can perform the near term objectives of volume reduction, stabilization, and water recovery, the intermediate term objective of recovering additional amounts of water and oxygen from waste materials, and the long term objective of a Controlled Ecological Life Support System (CELSS) and In-Situ Resource Utilization (ISRU).