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The Space Station ECLSS consists of two key components – the Water
Recovery System (WRS) and the Oxygen Generation System (OGS).
These systems will be packaged into three refrigerator-sized racks.
The Water Recovery System (WRS)
The WRS provides clean water by reclaiming wastewater (including
water from crewmember urine, hand wash, and oral hygiene waters);
cabin humidity condensate; and extravehicular activity (EVA) wastes. The
recovered water must meet stringent standards before it can be used to
support crew, EVA, and payload activities.
The WRS is designed to recycle crewmember urine and wastewater for
reuse as clean water. By doing so, the system reduces the net mass of
water and consumables that would need to be launched from Earth to
support six crewmembers by 2,760 kg (6,000 lbs) per year.
The WRS consists of a Urine Processor Assembly (UPA) and a Water
Processor Assembly (WPA). A low-pressure vacuum distillation process
is used to recover water from urine. The entire process occurs within a
rotating distillation assembly that compensates for the absence of gravity
and therefore aids in the separation of liquids and gases in space. Product
water from the UPA is combined with other wastewaters and delivered
to the WPA for treatment. The WPA removes free gas and solid materials
(hair, lint, etc.) from the water before it goes through a series of multiltra-
tion beds for further purication. Any remaining organic contaminants
and microorganisms are removed by a high-temperature catalytic reactor
assembly. The purity of product water is checked by electrical conductiv-
ity sensors (the conductivity of water is increased by the presence of typi-
cal contaminants). Unacceptable water is reprocessed, and clean water is
sent to a storage tank, ready for use by the crew.
This diagram shows the ow of recyclable resources in the International Space Station (ISS). The
regenerative Environmental Control and Life Support System (ECLSS), whose main components are
the Water Recovery System (WRS) and the Oxygen Generation System (OGS), reclaims and recycles
water and oxygen. The ECLSS maintains a pressurized habitation environment, provides water
recovery and storage, maintains and provides re detection/suppression, and provides breathable air
and a comfortable atmosphere in which to live and work within the ISS.
Astronaut Susan Helms, Expedition Two ight engineer,
is positioned near a large amount of water temporarily
stored in the Unity Node aboard the Internatonal Space
Station (ISS). The Water Recovery System (WRS) is
designed to recycle crewmember urine and wastewater
for reuse as clean water. By doing so, the system reduces
the net mass of water and consumables that would need
to be launched from Earth to support crewmembers by
as much as 2,760 kg (6,000 lbs) per year. The less water
launched, the less space needed for the stowing of water.
This is a close-up view of the Environmental Control and
Life Support System (ECLSS) Water Recovery System
(WRS) racks. The WRS provides clean water through the
reclamation of wastewaters, including water obtained
from the Space Shuttle’s fuel cells, crewmember urine,
used hand wash and oral hygiene water, cabin humidity
condensate, and Extravehicular Activity (EVA) wastes.
The Water Recovery System (WRS) is comprised of a
Urine Processor Assembly (UPA) and a Water Processor
Assembly (WPA). The UPA accepts and processes
pretreated crewmember urine to allow it to be processed
along with other wastewaters in the WPA, which
removes free gas, organic, and nonorganic constituents
before the water goes through a series of multiltration
beds for further purication. Product water quality is
monitored primarily through conductivity measurements.
Unacceptable water is sent back through the WPA for
reprocessing. Clean water is sent to a storage tank.
The water must meet stringent purity standards before
consumption by the crew.