H2O in Space: Waste Not, Want Not

Oct 27, 2021

Water is critical in space. This is especially true for NASA's planned long-term space missions, replete with on-board farming. At roughly 8.34 pounds per gallon, getting enough H2O aboard ship to irrigate crops and sustain astronauts is expensive, as every pound carried to space requires additional fuel, which incurs additional costs.

NASA worked with USDA's Agricultural Research Service (ARS) and research partner Pancopia, Inc., to develop a water recycling system that would help them save money and water in space. The two used a bacterial isolate called Brocadia caroliniensis, which was discovered in swine manure sludge on a North Carolina farm, to create a system that removes ammonia from wastewater. The process, called anaerobic ammonium oxidation (anammox) uses 60% less oxygen, no carbon, and is only one-third the cost of conventional biological nitrogen removal systems. Anammox can also be freeze dried for long-term preservation and quick reactivation.

The ammonia removal process involves passing wastewater heated to 71 F through an aerated vessel that contains anammox and other materials. As a result, 95% of wastewater is recycled into drinking water, which could reduce the amount of water NASA needs to carry onboard ship.

The high-performance water recycling system can be useful on Earth, too. Anammox can help livestock producers manage excess nutrients and emissions from animal waste, supply clean water to flush barns, irrigate crops, and provide purified drinking water for the pigs.

Matias Vanotti, soil scientist at the ARS Coastal Plains Soil, Water, and Plant Research Center in Florence, SC, worked with NASA to bring value to our nation through space-based research and technology development.