Abstract: With the emphasis of China on environmental issues，the emission concentration of SO2 is strictly limited.In some areas of Chnia，the emission mass concentration limits of SO2 have been required to be less than or equal to 20 mg/m3.There fore，polluting factories such as power plants and cement plants must take effective measures to control the emission concen tration of SO2.At present，the major classification of desulfurization technologies includes dry desulfurization，semidry desul furization and wet desulfurization.There are many technologies for each desulfurization method.In addition，the combined desulfurization technology developed by CenerTech Tianjin Chemical Research and Design Institute Co.，Ltd.has a good app lication in desulfurization of cement plants.The desulfurization process has the characteristics of wide use conditions，low construction and operation costs and high desulfurization rate，which can achieve ultralow emission of sulfur dioxide.More over，the desulfurization process does not introduce harmful elements such as potassium，sodium，chlorine，sulfur and phos phorus etc..Thus it does not affect the production process of the cement clinker.

Key words: dry desulfurization；semidry desulfurization；wet desulfurization；combined desulfurization