The Water Management on the Russian Segment of the International Space Station and Prospective Space Stations

"Implementation of promising orbital and interplanetary missions is associated with improvements in crew life support systems (LSS). One of the LSS key components are water supply systems. The systems should provide maximum recovery of water from water-containing products of life and from bioengineering systems meeting the needs of the crew in water with minimum water consumption from supplies. Experience in the design and operation of “Salut”, “Mir” and International space station (ISS) water supply systems as well as the use of supplies delivered made it possible to obtain the data on human water balance on the space station and the operation parameters of the recovery systems. The key factor is arising in the water recovery efficiency. Due to the energy, volume and mass restrictions at the near future the water recovery systems will be based on physical/chemical processes. The processes selected depend on the trace contaminant content in the feed liquid and the requirements for the water recovered: a sorption/catalytic and an ion-exchange processes for humidity condensate from the cabin and greenhouse atmosphere, distillate from urine processor and water from carbon dioxide reduction; membrane filtration (ultra filtration and reverse osmosis) with an ion-exchange post-treatment of hygiene water; the distillation method accompanied by distillate sorption/catalytic purification. The paper summarizes the experience gained with the RS ISS water management system during the missions ISS-1 (since November 2, 2000) through ISS-60. The performance data of the system for water recovery from humidity condensate SRV-K and urine feed and pretreatment system SPK-U in the Russian orbital segment are presented. The key role of water recovery on board the ISS and the need to supplement the Russian segment water supply hardware with a system for water reclamation from urine SRV-U is shown. The prospects of regenerative water supply system development are considered."