This Small Business Technology Transfer Phase I project will include a research program to prepare new materials for a novel sensor to detect when a water softener needs regeneration. The adoption of a low cost, accurate water hardness sensor can drive a substantial reduction in both the amount of salt released into municipal sewer systems and the amount of water used to rinse the resins. The patent-pending hardness sensor can replace more expensive and less effective components and approaches that are currently utilized by water softeners to initiate regeneration. This will enable penetration into markets which have been underserved due to environmental concerns about salt discharge. Manufacturers of softeners will benefit from the proposed hardness sensor, because it will modernize their regeneration controls while also improving water softening efficiency and environmental sustainability. Annual global water softener sales growth is around 8%. With a 15-20% market penetration, sensor sales could be around $90 million (water softener model). The proposed development of ion-exchange fibers is expected to have applications beyond hardness sensors. The same approach can be used to make anion-exchange fibers that can be employed for the detection of nitrate in devices similar to softeners to remove nitrate from drinking water. The intellectual merit of this project is the development of a new method for making ion-exchange fibers. The proposed work will build upon past research performed and will culminate in the development of commercially available cation-exchange fibers that can be used for hardness sensors and other applications. There is a substantial benefit of using the cation-exchange material of the hardness sensor. The sensor detects the electrical resistance of the entire mass of the cation exchange material between the electrodes. Earlier experiments indicate that cation-exchange fibers offer superior performance compared to membranes, but no commercially available fibers exist. After reliable fibers have been produced, they will be installed in hardness sensors to be evaluated using small column testing equipment at The University of Texas at El Paso, as well as in water softeners outside of the university to validate the salt and water savings potential. The proposed research will include not only sensor development, but also the measurement and control needed to automatically sense hardness and control regeneration in both a water softener resin bed and for the sensor itself.
