An Inside Look at the Water/Urine Recycling System on the Space Station

By Nancy Atkinson - April 26, 2013 06:43 PM UTC | Missions

International Space Station Commander Chris Hadfield "lifts the lid" on the Water Recovery System, the first liquid recycling system to be flown in space that cleans almost all the "water" (greywater, urine, sweat) produced by crew members so that it can be used again. As previous space station resident Don Pettit has said, "Yesterday's coffee becomes today's coffee."

Previously, Russia's space station Mir recycled cosmonaut's sweat, but this system on the ISS can recycle about 93 percent of the liquids it receives. The ISS's water recycler uses a distiller that looks like a keg.

On Earth, distilling is a simple process of boiling water and cooling the steam back into pure water. But without gravity, the contaminants in water never separate from the steam no matter how much heat is used. So, the keg-sized distiller spins to produce an artificial gravity field while boiling the water. The contaminants in the urine or greywater press against the sides of the drum while the steam gathers in the middle and is pumped to a filter.

Nancy Atkinson

Nancy Atkinson

Nancy Atkinson is a space journalist and author with a passion for telling the stories of people involved in space exploration and astronomy. She is currently retired from daily writing, but worked at Universe Today for 20 years as a writer and editor. She also contributed articles to The Planetary Society, Ad Astra (National Space Society), New Scientist and many other online outlets.

Her 2019 book, "Eight Years to the Moon: The History of the Apollo Missions,” shares the untold stories of engineers and scientists who worked behind the scenes to make the Apollo program so successful, despite the daunting odds against it. Her first book “Incredible Stories From Space: A Behind-the-Scenes Look at the Missions Changing Our View of the Cosmos” (2016) tells the stories of 37 scientists and engineers that work on several current NASA robotic missions to explore the solar system and beyond.

Nancy is also a NASA/JPL Solar System Ambassador, and through this program, she has the opportunity to share her passion of space and astronomy with children and adults through presentations and programs. Nancy's personal website is nancyatkinson.com