March 7, 2014 – NASA has awarded a multi-year contract to Reactive Innovations, LLC to continue its development work on a silver ion biocide delivery system for disinfecting water. U.S. space exploration missions have long considered returning to the Moon and exploration of Mars that challenge life support systems. For these long duration missions, NASA is interested in replacing the iodine water treatment system with ionic silver. Although iodine treated water has been used successfully with the International Space Station, its use requires that the iodine be removed before being consumed by astronauts due to its adverse effects on the thyroid. For long duration exploration missions, minimal mass systems are desired that lessen logistical supply requirements for storing and distributing potable water. In particular, it is imperative that an effective biocide is used that prevents microbial growth, biofilm formation, and microbially induced corrosion in the water storage and distribution systems. Reactive Innovations has previously demonstrated to NASA its electrochemical silver ion generator to produce an effective biocide solution for disinfecting water throughout the water storage and distribution system. Based on this successful demonstration, Reactive is further developing and optimizing the cell and control system. This biocide delivery system will be demonstrated in a relevant environment showing its long life performance for preventing biofilm growth.
Potable water treatment processes are needed to prevent microbial growth and biofilm formation in the water storage and distribution system for long duration missions. Silver ions have been proven by NASA to be effective for microbial control, however, there remain significant challenges with the biocide delivery system and materials of construction that are compatible with silver. Reactive’s process produces an effective delivery system with a control system that prevents silver deposition on the wetted materials of construction. This offers expanded degrees of freedom for designing the water system. Silver ion water treatment systems have been used in commercial systems for treating potable water. Reactive’s cell produces a better distribution of silver ions in the water system that minimizes concentration gradients that affect primary current distributions that contribute to spurious silver deposits elsewhere in the water flow system. Low energy requirements and inexpensive materials help drive Reactive’s technology toward commercial viability.