A semi-wet technological process for flue gas desulfurization by corona discharges at an industrial scale

Abstract An industry-scale semi-wet technological process for flue gas desulfurization by corona discharges is recommended. Its characteristics are: (1) it uses an ac/dc power supply to generate uniformly distributed streamer plasmas; (2) it uses a partitioned wet reactor system in which SO 2 in the flue gas is absorbed with ammonia water in its thermal chemical reaction stage and the generated solution is repeatedly sprayed and transferred at an appropriate flow rate to the successive plasma reaction stage under the conditions of keeping liquid flow in balance. In the plasma stage, SO 2 absorption by the liquid is enhanced by the electric wind and the sulfites in the solution experiences plasma oxidization; (3) drying up the end liquid to produce powder-typed byproduct and discharging the end gas after heat exchange with the hot gas at the inlet. Through a pilot test of 12,000 Nm 3 /h capacity of flue gas with an initial SO 2 concentration of about 500 ppm, results of desulfurization rate >95%, energy consumption in the reactor 1.8 Wh/Nm 3 , ammonia slip less than 5 ppm and qualified fertilizer byproduct are obtained.