Before recycling can begin, there has to be some water
to start with.
"We have plenty of water on the Space
Station now," says Jim Reuter, leader of the ECLSS group
at the Marshall Space Flight Center. "The Russian module
Zarya is packed with contingency water containers (CWCs)
that were carried over from the Space Shuttle during
assembly missions earlier this year. They look like
duffle bags and each one holds about 90 lbs.
"But it's expensive to ferry water
from Earth," he added. "We have to recycle. There's
already a Russian-built water processor in orbit that
collects humidity from the air. Here at Marshall we're
building a regenerative system that will be able to
recycle almost every drop of water on the station and
support a crew of seven with minimal resupplies.
"The ECLSS Water Recycling System (WRS),
developed at the MSFC, will reclaim waste waters from
the Space Shuttle's fuel cells, from urine, from oral
hygiene and hand washing, and by condensing humidity
from the air. Without such careful recycling 40,000
pounds per year of water from Earth would be required
to resupply a minimum of four crewmembers for the life
of the station.
Not even research animals are excused
from the program.
"Lab animals on the ISS breath and
urinate, too, and we plan to reclaim their waste products
along with the crew's. A full complement of 72 rats
would equal about one human in terms of water reclamation,"
says Layne Carter, a water-processing specialist at
the MSFC. It might sound disgusting, but water leaving
the space station's purification machines will be cleaner
than what most of us drink on Earth. "The water that
we generate is much cleaner than anything you'll ever
get out of any tap in the United States," says Carter.
"We certainly do a much more aggressive treatment process
(than municipal waste water treatment plants). We have
practically ultra-pure water by the time our water's
finished."
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