Search Results

Significant progress has been made at NASA Ames Research Center in the development of a heat melt compaction device called the Plastic Melt Waste Compactor (PMWC). The PMWC was designed to process wet and dry wastes generated on human space exploration missions. The wastes have a plastic content typically greater than twenty percent. The PMWC removes the water from the waste, reduces the volume, and encapsulates it by melting the plastic constituent of the waste. The PMWC is capable of large volume reductions. The final product is compacted waste disk that is easy to manage and requires minimal crew handling. This paper describes the results of tests conducted using the PMWC with a wet and dry waste composite that was representative of the waste types expected to be encountered on long duration human space exploration missions.

The initial concepts and construction of a three layered, water-absorbent, zero-G, compactor trash bag will be described. This bag is composed of an inner wicking layer, a middle absorbent layer, and an outer containment layer. The primary properties of the wicking layer are the fast adsorption of any free liquid released within the trash bag and the lateral spreading of this liquid around the interior of the bag. The absorbent layer sequesters and stores the liquid captured by the wicking layer. It need not be as fast acting as the wicking layer, but has to have a much larger capacity. The containment layer allows for handling of the bag without worry of releasing the contents. The combined strength of the three layers needs to be sufficient to withstand the forces exerted by the compactor.

The Vapor Phase Catalytic Ammonia Removal (VPCAR) Technology has undergone long duration testing at MSFC. The results of this testing revealed several areas in which the VPCAR Technology could be improved and those improvements are summarized here. These improvements include the replacement of several parts with units that are more durable, redesign of several pieces which proved to have mechanical weaknesses, and incorporation of some new designs in order to prevent other potential problems.

The success of physico-chemical waste processing and resource recovery technologies for life support application depends partly on the ability of gas clean-up systems to efficiently remove trace contaminants generated during the process with minimal use of expendables. Highly purified metal-impregnated carbon nanotubes promise superior performance over conventional approaches to gas clean-up due to their ability to direct the selective uptake gaseous species based both on the nanotube’s controlled pore size, high surface area, and ordered chemical structure that allows functionalization and on the nanotube’s effectiveness as a catalyst support material for toxic contaminants removal. We present results on the purification of single walled carbon nanotubes (SWCNT) and efforts at metal impregnation of the SWCNT’s.

Since the mid 1980s, NASA has developed advanced waste management technologies that collect and process waste. These technologies include incineration, hydrothermal oxidation, pyrolysis, electrochemical oxidation, activated carbon production, brine dewatering, slurry bioreactor oxidation, composting, NOx control, compaction, and waste collection. Some of these technologies recover resources such as water, oxygen, nitrogen, carbon dioxide, carbon, fuels, and nutrients. Other technologies such as the Waste Collection System (WCS - the commode) collect waste for storage or processing. The need for waste processing varies greatly depending upon the mission scenario. This paper reviews the waste management technology development activities conducted by NASA since the mid 1980s and explores the drivers that determine the application of these technologies to future missions.