ENHANCED CONTROL OF MERCURY IN A WET SCRUBBER THROUGH REDUCED OXIDATION AIR FLOW

摘要

A method and apparatus reduces mercury in industrial gas by reducing oxidation in the absorber reaction tank of a wet scrubber so that sulfites in the wet scrubber are increased to enhance mercury removal from the industrial gas. By controlling a rate of oxidation air flow supplied to a wet scrubber slurry within the absorber reaction tank at a reduced rate relative to that rate of oxidation air flow required to achieve nominally 100 % oxidation of the wet scrubber slurry, the wet scrubber slurry used to scrub the industrial gas contains a selected non-zero sulfite concentration sufficient to achieve greater mercury removal from the industrial gas. The selected sulfite concentration in the wet scrubber slurry is preferably greater than about 0.3 millimoles/liter.