Foaming in wet flue gas desulfurization plants: The influence of particles, electrolytes, and buffers

The objective of this work is to study the influence of particles, electrolytes, and buffers on the foaming ability of wet flue gas desulfurization (FGD) slurries. Foaming within this industrial process has been associated with a range of operational problems, as well as an increased degree of absorption. The foaminess of selected process parameters has been assessed, systematically, using laboratory-scale Bikerman experiments. Adipic acid alone, as well as a combination of small particles and an electrolyte, have been demonstrated to generate weak transient foams (with a Bikerman coefficient (Sigma) of <= 7s), that potentially can interfere with process monitoring equipment. Additional experiments with a wet FGD pilot plant showed an increased absorption efficiency of sulfur dioxide (SO2) by a tap water solution with small quartz particles and calcium chloride (CaCl2) compared to a solution of pure tap water.