Research On The Technics Of Desulfurization By Catalytic Reduction And Pulsed Discharge Plasma

Acid rain is one of the global environmental problems. The sulfur dioxide(SO2) from coal-fired electric plants is the leading cause of the acid rain in China, and this situation will not be altered in recent years because of the energy resources structure. Owing to its mature technics, wet limestone(lime)-gypsum flue gas desulfuration (FGD) process takes the dominant place around the world. But along with its complex system, bulky facilities, high cost in investment and function, also bringing huge waste water which needs aftertreatment, this system cann't be considered to be perfect. However, other approaches of FGD are confined by cost or technique for application.The direct reduction of SO2 to elemental sulfur by coupling of catalyst and plasma, being a new approach for SO2 reduction, is studied in this paper. In the process, CO acts as the reductant, SO2 is selectively reduced to elemental sulfur under catalyst and suitable conditions, and the residual SO2 will be disposed by the pulsed discharge plasma. This technics has its own advantages. For instance, the system is compact, and compared with other ordinary FGD process, it's not necessary to add any alkaline compound, which results in much less cost and secondary pollution. What's more, the end product of sulfur is a kind of important industry stuff.This paper was supported by the Office of Science & Technology of Wuhan. In this paper, two sets of process were designed, one was for coal-fired boiler gas in laboratory with the gas flux of 10Nm3/h, and another for power plant flue gas with the flux of 1670Nm3/h in Hubei Huadian Huangshi Electric Power Co. Ltd. Then, the apparatus of the two series were designed and made. The reaction conditions and their controlling skills were also concerned. After the equipments were set and adjusted, experiments were carried out, the efficiency of SO2 reduction achieved more than eighty percent when the gas flux was 1670Nm3/h and the SO2 inlet concentration was 1000~2000ppm. The end product was detected as elemental sulfur. Taking both technology and economy into consideration, this technics of desulfurization by catalyst and plasma is worthy for further experiment and application.