Harnessing Clean Water from Power Plant Emissions Using Membrane Condenser Technology

Power plants consume a major fraction of water to generate electricity, typically in the range between 30-50% of all fresh water sources. Most of the water from plants are lost with heat through stack and cooling towers. It has been reported that if 20% of this water can be recycled, power plants can be self sustainable, allowing them to be located with higher flexibility. Membrane contactor process can be an effective solution to harness this source of water, but most of the studies have been focused on dense vapor separation membranes with limited success. In this work, we investigated a potential application of membrane condenser technology to harness fresh water from power plants. It has been shown that the membrane condenser configuration can be 3 orders of magnitude more effective in recovering water compared to dense vapor separation membranes, with a reasonable water/SOx selectivity of 100. We have prepared suitable ceramic membranes as a proof-of-concept and achieved up to 85% dehumidification efficiency in a single-pass flow. A thorough energy balance indicates that both heat and water flux must be carefully balanced to maximize the membrane condenser performance, and an effective module design must be developed.