Process industry uses a lot of energy, which is costly and may result in global warming. Part of the energy consumption is connected to water, either because water is used to heat or cool processes or because energy is needed to treat waste water. Integration of energy consumption and water treatment can optimize utilities cost. TNO is developing several solutions.
Cooling water consumption can be reduced by membrane evaporators (Memstill), optimizing the cooling process in a flexible way and preventing legionella contamination in air. Waste heat in the water is used as a driving force for water distillation. This is a low energy cost treatment of water, yielding very pure water. This technique allows further integration with cooling processes. Energy can be produced from waste water by anaerobic treatment, which produces biogas. This process is further optimized by mixing agricultural waste in the sewage systems. Also, power production by electrochemical techniques is now investigated using biobatteries.
Another source of electrical energy and heat works with any water source. This technique is known under the name of Mempower ® and is now under development in the laboratory.