New brine processor technology is helping NASA astronauts reach a water reclamation milestone onboard the International Space Station.
Some of the key items on the station include a processor assembly that utilizes vacuum distillation and produces a urine brine that contains some reclaimable water. A brine processor extracts that remaining wastewater and sends it to the water processor assembly, which produces drinkable water and helps NASA achieve its 98% water recovery goal necessary for long-duration space exploration missions.
Prior to the development of the brine processor, NASA had maxed out at 94% water recovery. Now, the brine is sent through a special membrane technology, then blown dry to evaporate the water, creating humid air collected by the station’s water collection systems. The same process is used for astronauts’ breath and perspiration.
“This is a very important step forward in the evolution of life support systems,” explained Christopher Brown, part of the team at Johnson Space Center that manages the space station’s life support system. “Let’s say you collect 100 pounds of water on the station. You lose two pounds of that and the other 98% just keeps going around and around. Keeping that running is a pretty awesome achievement.”
Subscribe to our Newsletter!
The latest environmental engineering news direct to your inbox. You can unsubscribe at any time.
The water processor assembly uses a series of specialized filters, then a catalytic reactor that breaks down any trace contaminants that remain. Sensors check the water purity and unacceptable water is reprocessed. The system also adds iodine to the usable water to prevent microbial growth and stores it for crew use.
According to NASA, iodine is used for disinfection instead of chlorine because it is less corrosive and much easier to transport to the space station.
Each crew member needs about a gallon of water per day for consumption, food preparation, and hygiene such as brushing teeth.
Jill Williamson, NASA water subsystems manager, says the water reclamation process is fundamentally similar to some municipal water distribution systems, “just done in microgravity.”
“The crew is not drinking urine,” Williamson said in a statement from NASA. “They are drinking water that has been reclaimed, filtered, and cleaned such that it is cleaner than what we drink here on Earth. We have a lot of processes in place and a lot of ground testing to provide confidence that we are producing clean, potable water.”
Williamson added that the less water and oxygen taken into space, the “more science that can be added to the launch vehicle.” Efficient regenerative systems, she said, means the crew can focus on the “true intent of their mission.”