Also, safety aspects would benefit from a significantly-decreased dependency on resupply for long-range missions.
Typical waste-water streams likely to be used for water recovery are:
Problems for recovering water from the various sources by a regenerative system are typically linked to the presence of low molecular weight volatile compounds difficult to remove either by phase-change or by membrane technologies, to the presence of fouling compounds and, in all cases, to the presence of specific microflora liable to contaminate the water recovery system.
- condensate from the cabin temperature and humidity control system
- hygiene waters from personal hygiene and from dish and clothes washing units
- CO2 reduction water produced by air revitalisation systems
- phase change water from the stabilisation of trash and faeces by desiccation and
- experiment/laboratory water including evapo-transpiration water from experimental or food production green-houses
Studies dealing with water recovery undertaken by ESA have demonstrated the excellent potential of membrane-based technologies for purifying waste waters such as hygiene water and condensation water.
Successive studies have been undertaken by ESA-ESTEC which have demonstrated the excellent adaptation of membrane technologies to produce potable/hygiene water from low polluted waste waters such as shower and condensation waters.