The latest NASA technology, launched as part of Northrop Grumman’s 15th commercial replenishment service mission, is designed to improve water reuse at the International Space Station (ISS). In addition, it will increase the efficiency of water reuse for the Artemis lunar exploration mission.
The International Space Station Environmental Control and Life Support System (ECLSS) is a life support system that provides or monitors atmospheric pressure, fire detection and suppression, oxygen levels, waste management and water supply. The new Brine Processor Assembly (BPA) will be linked to the overall system and will allow more water to be extracted from the crew’s urine. This new technology will ultimately help scientists create more advanced systems that will find their way into future missions to the Moon and Mars.
The water recovery system provides clean water for use by astronauts by reusing urine, cabin moisture condensation from sweat, breathing and crew hygiene, and water derived from the air recovery system. The urine treatment unit, which is part of the water recovery system, is designed to recover 85% of the water from the crew’s urine. It has been significantly improved over the past year and is now restoring 87%. “This distillate is combined with condensate and treated with a Water Treatment Facility (WPA) that recovers 100% of the treated water,” explains Lane Carter, ISS Water Subsystem Manager in Marshall. “As a result, the overall water recovery is about 93.5%.”
Astronaut crews on long exploration missions will need ECLSS systems to recover approximately 98% of the water they bring with them at the start of their voyages.
To leave low Earth orbit and allow long-term exploration away from Earth, we need to close the water loop. Modern urine water recovery systems use distillation to form a saline solution. The brine treatment system receives this water-containing wastewater and extracts the remaining water.
Caitlyn Meyer, Associate Project Manager for Life Support Systems at NASA Johnson Space Center
Once installed in the station’s Tranquility module, the BPA will pump brine from an advanced recirculating filter assembly into a dual membrane cylinder. This chamber will selectively let water vapor into the cockpit atmosphere. Once in the atmosphere, water will be drawn out of the air by another part of the water recovery system, a condensing heat exchanger. The heat exchanger will send the moisture back to the water treatment unit, where it is converted back to drinking water. Used BPA cylinders will be removed and stored and eventually discarded or returned to Earth for study.
“With this new brine treatment device, we will be extracting additional water from the brine produced by the urine treatment device, so the overall water recovery is close to 98%,” concludes Carter.
The brine treatment system will ultimately help support long-term crewed exploration missions and reduce the need for replenishment of water from Earth.