Search Results

Management of human feces and wastes is a major challenge in space vehicles due to the potential biohazards and malodorous compounds emanating during collection and storage of feces and wastes. To facilitate safe, yet realistic human waste management research, we have previously developed human fecal simulants for research activities. The odoriferous compounds in feces and wastes reduce the quality of life for astronauts, can reduce performance, and can even cause health problems. The major odoriferous compounds of concern belong to four groups of chemicals, volatile fatty acids, volatile sulfurous compounds, nitrogenous compounds and phenols. This paper attempts to review the problem of odor detection and odor control with advanced technology. There has been considerable progress in odor detection and control in the animal industry and in the dental profession.

The microgravity environment of space introduces a major new variable for consideration that will affect the design and operation of bioreactors. Adequate aeration for aerobic bioreactors will be a challenge as will gas/liquid separation, removal of carbon dioxide and other bacterial metabolic waste products, control algorithms, and overall performance assessment. These challenges must be addressed in order to fully assess the efficacy of biological approaches to the recovery of potable water from wastewater in microgravity. The first step in this process is to define the fermentation parameters of the organism or consortia that will be used in these space bioreactors. This study was designed to investigate the ability of bacteria to degrade the space station detergent IGEPON.

CO2 removal, recovery and reduction are essential processes for a closed loop air revitalization system in a crewed spacecraft. Typically, a compressor is required to recover the low pressure CO2 that is being removed from the spacecraft in a swing bed adsorption system. This paper describes integrated tests of a Temperature-Swing Adsorption Compressor (TSAC) with high-fidelity systems for carbon dioxide removal and reduction assemblies (CDRA and Sabatier reactor). It also provides details of the TSAC operation at various CO2 loadings. The TSAC is a solid-state compressor that has the capability to remove CO2 from a low-pressure source, and subsequently store, compress, and deliver it at a higher pressure. TSAC utilizes the principle of temperature-swing adsorption compression and has no rapidly moving parts.

This paper describes the results of an ongoing long-duration testing of a temperature-swing adsorption compressor (TSAC) that has application in closing the air revitalization loop of the International Space Station (ISS) and future spacecraft. The TSAC is a solid-state compressor that has the capability to remove CO2 from a low-pressure source, and subsequently store, compress, and deliver it at a higher pressure as required by a processor. The TSAC described in this paper was designed to function as an interface device for the CO2 removal and reduction units of the International Space Station (ISS). The air revitalization system of the ISS operates in an open loop mode and relies on the resupply of oxygen and other consumables from Earth for the life support of astronauts. A compressor is required for recovering the CO2 from the carbon dioxide removal assembly (CDRA) and delivering to a CO2 reduction unit of an oxygen recovery system and thereby closing the air-loop.

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.