Demonstration of Water Recovery from Hot, Humid, Industrial Exhaust Gases

This project included the detailed industrial design and thermal and heat transfer modeling of a thermal ejector-based system to recover water from hot, humid exhaust gases generated in industrial facilities. The project focused on modeling, designing, and fabricating a skidmounted system to recover 100 gallons of water per hour from exhaust gas vented from a United States Gypsum Corporation wallboard plant in Plaster City, California. The skid processes a small portion of the exhaust gas from the stack, and returns the cooled, drier, processed exhaust gas to the stack. 

Baseline measurements on the demonstration plant stack have been matched with the demonstration unit design and equipment. Demonstration testing was carried out over a sixmonth period. The team collected operational data and then added that data with analyses to this Final Report. The demonstration unit is designed to optimize performance over the full range of ambient air temperatures. Five operating regimes have been identified, and the controls of the fans and heat exchangers are set to work in these various regimes. Details of the five regimes are presented in this report. This approach allowed the project team to optimize system performance and minimize power required per gallon of water recovered.

This Final Report includes the Measurement and Verification report from subcontractor Tetra Tech. A Technology Transfer Plan is also included to provide information on the path toward commercialization of the demonstration water recovery technology.