Air Pollution Control Equipment Selection Guide, 3rd Edition

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Spray Tower Optimization

Spray towers basically disperse by using pressurized spray a high surface area liquid stream counterflow (primarily) into a gas stream containing contaminants and/or heat. The purpose of the design is to efficiently affect the transfer of mass and/or heat into the liquid. The liquid is then constantly drained from the spray tower. The word “primarily” is used because some of the liquid is inherently carried upward in the vessel (sometimes called “back-mixing”) given the movement of the gases. Unless the contaminant is absorbed quickly and is rapidly neutralized (retained in solution by being converted to a low partial pressure salt or oxide), movement of the liquid upward can reduce the net efficiency of the spray ...