Waste heats recovery from industrial wastewater
Wastewater usually contains so called waste heat. Could this heat also be reclaimed?
Great amounts of pure water are used yearly by industry. Water is used, for example, as raw material and for purification processes. Part of the used water ends up in wastewater treatment facilities as wastewater. This wastewater usually contains so called waste heat. For example, certain breweries use the incoming raw water the temperature of which is approximately 10̊ C. Accordingly, the breweries out flowing wastewaters temperature is 20 – 30̊ C. This heat could also be reclaimed.
Wastewaters waste heat recovery, however, it has its own problems which must be resolved before a recovery can be profitable. Thermal recovery of waste water is not able to be undertaken profitably with traditional heat exchangers. This is a consequence of water temperatures being so low that the properties of heat exchangers can´t achieve a reasonable outcome. Effluent containing suspended solids also causes its own problems.
Could heat pump technology be used instead of heat exchangers? The heat pump enables the use of thermal energy recovery with lower temperatures.
Wastewater reclamation in high-tech countries is a challenge for the present and the future. Industrial waste heat generation is trying to avoid but its emergence cannot be completely prevented. However, energy conservation is very important to its ever rising prices and consumption. Even today water thermal energy has not been extensively exploited.
Research question: Even today wastewaters thermal energy has not been extensively exploited.