The present invention relates in general to wet flue gas desulfurization (FGD) processes and, in particular, to wet limestone forced oxidized flue gas desulfurization processes (LSFO-FGD) processes and other compatible processes. Wet LSFO-FGD systems have separate oxidation air and limestone slurry streams. These systems, in general, utilize a wet grinding circuit by grinding coarse limestone to prepare a limestone solids-liquid slurry as the fresh reagent supplied to the absorber system. Typically, wet ball mills have been used for this purpose. The wet comminution process has the advantage of potentially lower horsepower requirements than dry grinding processes, and the fact that the end product after grinding is a slurry also fits in well with the wet LSFO-FGD system design. This slurry is commonly stored in a holding tank to provide surge capacity for subsequent controlled supply to the absorber vessel based on demand.
In wet FGD systems, the sulfur dioxide (SO.sub.2) absorption process requires a nearly continuous supply of fresh reagent to maintain satisfactory operation and SO.sub.2 removal efficiencies. Often it is desirable to incorporate air addition to the wet FGD absorber to provide in situ forced oxidation of the absorber reaction product.
Providing separate oxidation air and limestone slurry streams increases the complexity and expense of these wet LSFO-FGD systems. It is thus apparent that an approach to providing these separate functions in a simple and cost-effective manner would be welcomed by the industry.