Through analysis of chemical principles in lime-stone/gypsum wet FGD system

an approach to the chemical mechanisms related to the influence of operation factors upon fouling in said system has been made

and preventive measures being put forward on this basis as in the following:(1) the precipitation process of crystals CaSO3/CaCO4 should be completed in the circulatory slurry pond as possible;(2) maintaining uniform agitation in the slurry

lengthening the retention time of slurry in the slurry pond

and enhancing the content of crystalline solids in the slurry;(3) enhancing the utilization coefficient of lime-stone;(4) enhancing the liquid/gas ratio under condition allowable in economy and design;(5) suitably enhancing the concentration of gypsum solids in the process of forced oxidation;(6) using the time gap of shutdown

timely cleaning the soft scale of CaSO3 manually

and temporarily reducing the pH value in operation

so as to resolve the CaSO3 scale formed already in the system.