Development of a Personal Water Reclamation System (PWRS)

The personal water reclamation system (PWRS) is a passive water treatment bag that is designed for emergency use. The PWRS produces an engineered drink or food product from contaminated water. It uses a pervaporation membrane that allows passage of the water vapor present in the feed solution and makes it condense on the product side. The bag is designed to be used independently or integrated into the crew’s pressure suit. It uses the osmotic potential between the feed and the product to drive the purification process. The PWRS uses a concentrated sugar or food solution as the osmotic agent. The urine feed provides water which is essentially distilled and used to dilute the osmotic draw solution to a level appropriate for direct human consumption. The PWRS provides the needed supply of hydration fluids, calories and electrolytes while substantially reducing the mass required for stored emergency supplies. The quality of the product solution is extremely pure, since the amount of total organic carbon is reduced to a few parts per million in the evaporation/condensation process. Gas chromatography of the product shows semi-volatile organics to be below detection limits. This paper describes the development of the PWRS and its preliminary testing in the lab and operational environment.