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This paper addresses the development of a novel technology to simultaneously reduce total organic carbon (TOC) and microbial count (MC) in biological water processor (BWP) processed water. This approach also creates a biocidal environment in BWP processed water before being fed into the reverse osmosis (RO) and post processing systems. The technology is based on an advanced oxidation process using an on-demand oxidizer generator, which does not require consumable chemicals. The SBIR (Small Business Innovation Research) Phase I feasibility studies successfully demonstrated the process efficacy in the reduction of both TOC and MC of the BWP effluent. Also, the residual disinfectant and reduced TOC in the treated effluent minimized fouling the RO membrane and water lines. In the Phase II project, a prototype is being fabricated and evaluated for its ability to reduce TOC and MC, and extend RO membrane life.

Potable and hygiene water availability is a critical requirement for long-duration manned space missions. Frequent water quality testing helps to ensure astronaut health by providing needed feedback on the effectiveness of on-board water purification units. One of the most basic and broad-spectrum indicators of contamination is organic carbon concentration. To meet the need for water quality feedback on the International Space Station (ISS), as well as on planned missions to Luna and Mars, Lynntech is developing a mesofluidic total organic carbon analyzer (TOCA) through the NASA SBIR program. The unit has been designed to operate in the demanding environment of a long-duration manned space mission and addresses the issues of microgravity operation, an operating lifetime of 5 years, low power consumption, simple user interface, robust architecture, and inherent safety.

The purification of reclaimed water is essential to water reclamation technology life-support systems in lunar/Mars habitats. Lynntech, Inc., working with NASA-JSC, is developing an electrochemical UV reactor which generates oxidants, operates at low temperatures and requires no chemical expendables. The reactor is the basis for an advanced oxidation process, in which electrochemically generated ozone and hydrogen peroxide are used, in combination with ultraviolet light irradiation, to produce hydroxyl radicals. Results from this process are presented which demonstrate concept feasibility for removal of organic impurities and disinfection of water for potable and hygiene reuse. Power, size requirements, Faradaic efficiency and process reaction kinetics are discussed. At the completion of this development effort, the reactor system will be installed in JSC's regenerative water recovery test facility for evaluation to compare this technique with other candidate processes.

Practical solar powered aircraft require an efficient energy storage system to store energy during the day for use at night. Hydrogen and oxygen, generated by electrolyzing water during the day and recombined at night to generate electricity, has a theoretical energy density of 3.73 kWh/kg. Harnessing this potential has been approached with a combination of a lightweight PEM electrolyzer and a lightweight PEM fuel cell with a new stack structure utilizing metallurgical bonding to assemble thin metal gas barriers with lightweight metal flow fields. This design minimizes size, weight, electrical resistance, and part count. This technology has been demonstrated to produce efficient and effective stacks.

The development of a new microfluidics based carbon analyzer that is capable of generating chemicals needed in the analysis is described. The analyzer design is based on several components, an electrochemical cell, a membrane conductivity sensor, and an electrochemical water de-ionizer, which utilize porous membranes such as proton exchange membrane, gas separation membrane, and ion exchange membrane n their operation. These membrane-based microfluidic devices (MBMD) allow miniaturization of the carbon analyzer into a compact instrument which will provide high sensitivity and low power consumption. Each of the membrane-based microfluidic components was fabricated and their functioning tested over a broad range of inorganic or organic carbon content in water samples.

In bioregenerative life support systems, crop residues represent a source of biochemical energy for production of chemicals, pulp products and secondary foods. Hydrolysis of the structural carbohydrates in biomass produces edible glucose as well as various 5-carbon sugars usable by microorganisms. However, the biomass must be pretreated before hydrolysis to remove minerals useful as plant nutrients, break down lignin, and improve access of the enzymes to the carbohydrates. Some pre-treatments also hydrolyze part or all of the hemicellulose, leaving purified cellulose. For use in space, pretreatments must be safe, rapid and as complete as practicable. This paper will present a process comparison of three “space-compatible” pretreatment methods for lignocellu-losic crop residues from bioregenerative life support systems. Ozonation, alkaline hydrogen peroxide, and strong alkali treatment use only regenerable materials and mild processing conditions.

A compact, low-power, electrochemically driven fluid cooling pump is currently being developed by Lynntech. With no electric motor and lightweight components, the pump is significantly lighter than conventional rotodynamic and displacement pumps. Reliability and robustness are achieved with the absence of rotating or moving components (apart from the bellows). By employing sulfonated polystyrene-based proton exchange membranes rather than conventional Nafion® membranes, a significant reduction in the actuator power consumption was demonstrated. Lynntech designers also demonstrated that these membranes possess the mechanical strength, durability, and temperature range that are necessary for long-life space operation. The preliminary design for a prototype pump compares very favorably to the design targets of the next generation spacesuit Portable Life Support Systems cooling pump.