Water recovery using waste heat from coal fired power plants.

The potential to treat non-traditional water sources using power plant waste heat in conjunction with membrane distillation is assessed. Researchers and power plant designers continue to search for ways to use that waste heat from Rankine cycle power plants to recover water thereby reducing water net water consumption. Unfortunately, waste heat from a power plant is of poor quality. Membrane distillation (MD) systems may be a technology that can use the low temperature waste heat (<100 F) to treat water. By their nature, they operate at low temperature and usually low pressure. This study investigates the use of MD to recover water from typical power plants. It looks at recovery from three heat producing locations (boiler blow down, steam diverted from bleed streams, and the cooling water system) within a power plant, providing process sketches, heat and material balances and equipment sizing for recovery schemes using MD for each of these locations. It also provides insight into life cycle cost tradeoffs between power production and incremental capital costs