On our last trip to Uganda, we were accompanied by Michael Flynn, a life-support engineer at NASA Ames Research Center in Moffett Field, CA.
The following is from an article by Boonsri Dickinson at smartplanet.com:
Flynn has a pretty important job. We works on technologies required to keep humans alive in space.
But launching clean water into space is cost-prohibitive, so for years, Flynn and his team have working on new ways to recycle waste water into safe, drinking water.
“Space flight is extremely expensive and the expensive part is launch costs. So NASA [is] developing water recycling systems that allow us to recycle all waste water that is produced on board a spacecraft, [and that includes recycling] all waste water that is produced on board a spacecraft,” Flynn said.
In other words, Flynn’s system allows astronauts to drink their own urine.
The water [treatment system] uses a process know as forward osmosis. This system uses the potential difference between salt water and fresh water to transport water across a semi-permeable membrane, while leaving all the contaminants behind.
“The membranes are the key to the technology. They are generally a flat sheet of some sort of paper material with a polymer put on them, and they allow water to transfer through them but do not allow salts or large organic molecules to transport through them,” Flynn explains.