Low-Pressure Plasma Assisted Waste Conversion

Date

7/12/2021

Journal Title

Journal ISSN

Volume Title

Publisher

50th International Conference on Environmental Systems

Abstract

The commercialization of space and advancement of modern technologies have led to expected human presence beyond Low Earth Orbit. With this, alternative technologies for the reusability of human-generated waste streams becomes necessary. An interesting such technology is the conversion of waste to gas via the employment of plasma and plasma technology. Low power plasma-assisted waste conversion technology has not been greatly explored under space-like conditions. Presented in this report is a DC plasma discharge operating under one kilowatt without any feedstock gas flow and in rough vacuum conditions. Materials of interest used in the study are typical of astronaut waste streams such as cloth, food packaging, plastics, and cleaning materials. The removal of a feedstock gas explores gasification percentages without the use of a consumable in the previously explored plasma torch setup. The average solid to gas conversion in the highly exploratory setup was around 36%. This number is expected to be greatly increased with electrode position optimization and waste stream pre-processing. The by-product gases were captured and analyzed using gas chromatography which showed generation of H2, CO2, CO, C2H4, CH4, H2O, and other hydrocarbons. This text reports on the plasma gasification percentages, temperature and pressure profiles, liquid condensate analysis, reaction mechanisms, and viability of a low pressure, low power plasma for waste conversion without a feedstock gas.

Description

Kenneth Engeling, NASA
Malay Shah, NASA
Misle Tessema, NASA
ICES304: Physio-Chemical Life Support- Waste Management Systems- Technology and Process Development
The 50th International Conference on Environmental Systems was held virtually on 12 July 2021 through 14 July 2021.

Keywords

plasma, gasification, waste conversion, syngas, vent gas, space waste

Citation