Qualities of Limestone That Influence Wet FGD Performance

摘要

With the projected rapid growth in flue gas scrubber construction, plant personnel at facilities where wet flue gas desulfurization (WFGD) is selected will be tasked with choosing the proper reagent for the system. In wet scrubbers, sulfur dioxide (SO2) must be transferred from the gas phase to the liquid phase. Without going into additional detail, most wet-limestone scrubbers are equipped with forced-oxidation systems to convert reaction products into a final byproduct of gypsum. What this article wishes to examine is how limestone impurities affect the efficiency of the scrubbing process. The upshot is that owners, operators and chemists of planned wet-limestone FGD systems should carefully evaluate the quality of limestone reagent to be used and discuss these issues with the equipment supplier. Good upfront work can prevent operating nightmares later. In addition to basic chemistry analyses, relatively straightforward tests are available to evaluate limestone reactivity before any material is accepted for use.