Odor Control in Spacecraft Waste Management

Spacecraft and lunar bases generate a variety of wastes containing water, including food wastes, feces, and brines. Disposal of these wastes, as well as recovery of water, is necessary. However, evaporation of water also evaporates compounds with foul odors, some of which are much more volatile than water. Even apart from a water recovery system, foul odors sap crew morale, and must be eliminated. NanoScaleREG Corporation has developed a formulation of its proprietary sorbents, termed OdorKlenzTM, that has been shown to effectively remove odorous compounds from air by destructive adsorption. NanoScale proposes development of a similar formulation, built around nanocrystalline metal oxides manufactured by NanoScale's proprietary procedures, such as NanoActive TiO2, NanoActive MgO, and NanoActive ZnO, to remove foul odors in a system that can recover water from wastes. The odor control system will function during waste storage, and also during water recovery . In Phase I, NanoScale will demonstrate feasibility by developing a formulation of metal oxides capable of removing odorous compounds from food and sanitary wastes, and compatible with a water recovery system. Specific test compounds include skatole (3-methylindole, found in feces), putrescine (1,4-diaminobutane, in rotten protein), ammonia (urine), ethanethiol, hydrogen sulfide (rotten eggs, flatus), butyric acid (rancid butter), and butyraldehyde. Gas streams containing these compounds will be passed through beds of the metal oxide formulation, with concentrations measured by GC, before and after passing through the bed. In Phase II, the odor control system will be integrated into the specific details of spacecraft and envisioned lunar stations. Then, brassboard hardware will be developed and evaluated. NanoScale, having pioneered the synthesis and manufacture of nanocrystalline metal oxides for destructive adsorption of hazardous compounds, is uniquely qualified to perform the proposed work.