System and a rotary vacuum distiller for water recovery from aqueous solutions, preferably from urine aboard spacecraft

A system for water recovery from urine aboard spacecraft, comprising:

• a urine intake and pretreatment unit comprising:
• a urinal for receiving urine forced to be moved by a stream of transport air, having an outlet,
• a separator for separating the transport air from said urine, having an inlet connected to said outlet of the urinal, and an outlet,
• a means for storing and feeding pretreatment chemicals, having all outlet connected to said inlet of said separator,
• a tank for separated urine, connected to said outlet of said separator,
• a unit for water reclamation from urine downstream of said urine intake and pretreatment unit, communicated therewith by a urine feed line and comprising:
• a rotary vacuum distiller for distilling the separated urine, having a rotary drive and comprising at least a first stage and a last stage arranged successively and coaxially and having each an evaporation surface and a condensation surface and a condensate collection chamber, communicated with each of said condensation surface,
• a urine circulation loop coupled to said first stage,
• a urine brine tank connected through a controlled valve to said urine circulation loop,
• a vapor circulation loop for vapor extracted from said last stage of said rotary vacuum distiller and delivered to the condensation surface of said first stage, a heat pump made as a vapor compressor being installed into said loop,
• a condensate circulation loop coupled to said condensate collection chamber,
• a line for die removal of noncondensable gases, coupled to a central part of said condensate collection chamber,
• a line for discharging condensate, coupled to a peripheral part of said condensate collection chamber,
• a unit for purifying said condensate to water grade recovered from the urine having an inlet to which said line for discharging condensate is coupled.

A rotary vacuum distiller for water recovery from urine aboard spacecraft, comprising:

• a casing,
• a hollow rotor rotatably mounted in said casing,
• a rotary electric motor for said rotor,
• at least two stages, a first stage and a last stage, arranged successively and coaxially in said rotor for rotating therewith,
• each of said stages being formed by at least one heat-transfer plate whose one side is an evaporation surface and the opposite side is a condensation surface,
• separation plates whose number corresponds to the number of said stages of the distiller, arranged in said rotor coaxially therewith in succession behind each of said heat-transfer plates,
• condensation zones formed between said condensation surfaces of the heat-transfer plates and separated from evaporation zones by said separation plates,
• water seals for precluding vapor overflow, disposed in said evaporation zones between said stages of the distiller,
• disks with openings for the removal of noncondensable gases, mounted in said condensation zones coaxially to said rotor and forming with the wall of said rotor water seals for condensate overflow,
• a chamber for collecting condensate and noncondensable gases, disposed behind said last stage coaxially therewith and communicated through said water seals of condensate overflow and said openings in said disks with all said condensation zones,
• a pipeline for feeding an aqueous solution to be evaporated to an evaporation zone of said last stage of the distiller,
• channels for overflow of the aqueous solution among said evaporation zones,
• means for distributing the aqueous solution being evaporated among said evaporation surfaces of the heat-transfer plates,
• a loop for the circulation of the aqueous solution being evaporated between a peripheral part of an evaporation zone of said first stage and a central part of the evaporation surface of the heat-transfer plate of the same zone,
• a means for supplying heat to said first stage for the evaporation of the aqueous solution,
• a means for removing heat from said last stage,
• a line for discharging condensate, connected to the peripheral part of said chamber for collecting condensate and noncondensable gases,
• a line for the removal of noncondensable gases, connected to a central part of the chamber for collecting condensate and noncondensable gases,
• a line for discharging concentrate of said aqueous solution being concentrated, coupled to said loop for the circulation of the aqueous solution being evaporated.