Right now, astronauts on the International Space Station use a carbon-based filter to purify water extracted from urine.
An experiment heading up next week to the space station could help landlubbers down here on Earth conserve water by doing a better job of filtering out chemicals, salts or other contaminants. It could even be a lifesaver for drought-stricken Californians who are desperate for new sources of water.
The water filtration experiment uses aquaporins, or tiny channels in human and plant cells, that only allow water molecules to pass in between the cell membrane.
In ground tests, the aquaporin membrane does a better job at filtering contaminants than the current activated carbon-based filter system on the International Space Station, according to Michael Flynn, a physical scientist at NASA’s Ames Research Center.
Flynn says the new aquaporin filter would last longer, and eliminate the need to replace water filters on resupply missions.
“If you are going to Mars, there not going to have any resupply,” Flynn said. “We need water supply systems to be very reliable and not have any replacement parts.”
Right now, astronauts recycle all their water on ISS, including water extracted from urine, and water vapor from astronauts breathing that is exhaled into the tiny crew quarters.
However in recent months, the ISS crews have had to stop recycling their water because of delays in the launch vehicles that were supposed to bring in the new filters.
There’s also this. Over time, NASA has noticed a buildup of a non-toxic compound called diethyl phthalate, which Flynn describes as a “new-car smell” from decomposing gaskets, glues, plastics
and rubber pieces inside the station.
Even though it doesn’t pose a human health risk, the problem is that diethyl phthalate could be masking other potentially harmful chemicals in the water system.