Purified urine to be astronauts' water
Reuters Page 17 2008-11-16 12:57 AM

As NASA prepares to double the number of astronauts living aboard the International Space Station, nothing may do more for crew bonding than a machine being launched aboard the space shuttle Endeavour on Friday.
It's a water-recycling device that will process the crew's urine for communal consumption.
"We did blind taste tests of the water," said NASA's Bob Bagdigian, lead engineer. "Nobody had any strong objections. Other than a faint taste of iodine, it is just as refreshing as any other kind of water. It tastes fine to me."
Delivery of the US$250 million wastewater recycling gear is among the primary goals of NASA's 124th shuttle mission.
In addition to the water recycler, Endeavour carries two small bedrooms, the station's first refrigerator, new exercise gear, and perhaps most important for a growing crew - a second toilet. NASA wants to make sure the water recycling system is working well before adding another three astronauts to the station's crew.
Reusing water will become essential once NASA retires its space shuttles, which produce water as a byproduct of their electrical systems. Rather than dumping the water overboard, NASA has been transferring it to the space station.
But the shuttle's days are numbered. Only 10 flights remain, including a final servicing call to the Hubble Space Telescope. NASA is preparing to end the program in 2010.
"We can't be delivering water all the time for six crew," said space station flight director Ron Spencer. "Recycling is a must."
NASA expects to process about six gallons (23 liters) of water per day with the new device. The goal is to recover about 92 percent of the water from the crew's urine and moisture in the air.
The wastewater is processed using a series of purification techniques, including distillation - which is somewhat tricky in microgravity - filtration, oxidation, and ionization.
The final step is the addition of iodine to control microbial growth, Bagdigian said.
The device is intended to process a full day's worth of wastewater in less than 24 hours.
"Today's drinking water was yesterday's waste," Bagdigian said.