Conceptual design of an SOx scrubber system utilizing plant waste

The use of ash pond water and cooling tower blowdown as possible SO_x scrubber liquors has been studied. Information on analysis of ash pond water indicates that this method may be feasible. lt was found that ash from the furnace contained salts which could be used to absorb SO_x in the scrubber. This would. significantly reduce the cost of lime or limestone addition to the scrubber water as presently proposed. Blowdown from cooling towers using sulfuric acid for calcium carbonate scale control does not appear to be an acceptable scrubber liquor. However, the makeup water may be passed through a flue gas cooler where a portion of the sulfur dioxide (SO₂) and sulfur trioxide (SO₃) are absorbed and the flue gas cooled before entering the scrubber.

A scrubber design has been proposed which allows cleaning a portion of the scrubber packing while the scrubber is operating.

A comparison of reheat versus fan power to assist in flue gas removal via the stack was made. A fan which would disperse the flue gas will be more economical if the maintenance costs of the fan and the saturated plume emitted from the stack at a high velocity are compatible.