Microwave Powered Solid Waste Stabilization and Water Recovery

A Microwave Powered Solid Waste Stabilization and Water Recovery system is proposed as the primary step in the treatment of solid waste materials generated during extended manned space missions. The system will recover water initially contained within wastes and stabilize the residue with respect to microbial growth. Dry waste may then be safely stored or passed to the next waste treatment process. Using microwave power, water present in the solid waste is selectively and rapidly heated. Liquid phase water flashes to steam and superheats. Hot water and steam formed in the interior of waste particles create an environment that is lethal to bacteria, yeasts, molds, and viruses. Superheated steam contacts all exposed surfaces and provides an effective thermal kill of microbes, in a manner similar to that of an autoclave. Both water and heat are recovered in a condensing heat exchanger, with further water reclaimed from saturated air by adsorption, using microwave regenerable sorbents. Benefits of microwave power include rapid heat-up and cool-down, and selective heating of water by the direct absorption of electromagnetic radiation, thus minimizing conductive and convective losses. This translates directly into reduced size and power requirements, and lower Equivalent System Mass (ESM).