The technology of: Limestone - gypsum desulfurization for process has a long development history, with the recent in-depth research and constant improvement, the technology is mature, high desulfurization efficiency, stable operation, good adaptability to coal desulfurization agent, rich source and low price, features of desulphurization by-product comprehensive utilization has become the mainstream of domestic desulfurization industry. Desulfurization process: pot (kiln) furnace flue gas passes through the fan, into the reaction zone of desulfurization absorption tower, downward out suspended droplet countercurrent contact with the absorber spray pipe, mass transfer and absorption reaction, removal of SO2, SO3 and HC1, HF. The flue gas desulfurization by removing the droplet removal from flue gas entrained mist from the top left, absorption tower, is discharged from a chimney. SO2 and SO with limestone slurry reaction, formation of calcium sulfite and calcium sulfate. The calcium sulfite oxidation of calcium sulfate in the absorber slurry pool of bone such as air, the crystallization of calcium sulfate hemihydrate gypsum (CaSO4 into. 2H2O). After the by-product gypsum filter dewatering. The performance guarantee: The desulfurization efficiency of FGD ¡Ý 95% Calcium sulfur ratio Ca/S (molar ratio) is less than 1.05 Flue gas desulfurization system can utilization rate of not less than 98% The pressure drop: 800-1200Pa The demister after the flue gas moisture content: less than 75mg/Nm Variation range of load: 30-130% Power consumption: about unit capacity 1.0%-1.2%