Water Supply of Long-Term Space Flights on the Basis of Physico-Chemical Processes for Water Regeneration

Due to the energy, volume and mass restrictions the physical-chemical processes of water and atmosphere recovery will be used on the space station in the near future. The use of biological processes for a food production are the aims of the future. At the present the structure of physical-chemical regenerative life-support complex has been formed. The regeneration systems need to realize the maximum recovery of water and oxygen from liquids waste, serving the needs of the crew with minimal use of reserves. The main methods of water regeneration were formed based on the research and development works:

• sorption-catalytic method for humidity condensate, the distillate from urine system, water from the CO2 reduction in Sabatier reactor, the condensate of the vapors formed during drying of the waste;
• distillation for water reclamation from urine;
• reverse osmosis with pre filtration and subsequent sorption and the bacterial purification of the regenerated water. Small-sized equipment, working in conditions of space flight is developed to implement these methods. Self-sufficiency of the life-support complex is determined by the coefficient of water recovery in the case where the oxygen is produced from reclaimed water and food from stocks. The recovery rate achieved on the space stations were: “Salyut” - 38%; “Mir” - 72%; ISS (Russian segment) – 38%; ISS in the future – 88%; space station with a full range of regenerative life support systems – more than 94%. The minimization of mass of the LSS complex is provided with its maximum self-sufficiency and maximum efficiency of the systems. The report is based on the "Mir" and ISS operation data for water balance of different variants of LSS complex design and technology, energy-and-mass characteristics of modern and perspective systems of water regeneration and includes recommendations for LSS regenerative complex of future space stations.