This technology has the advantages of less investment, small area and simple process. Moreover, the desulfurization efficiency similar to that of wet desulfurization technology can be achieved at a very low calcium sulfur ratio. RCBF technology can select slaked lime, quicklime and coke as absorbents according to the capacity of the unit and the requirements of emission control. RCFB can also be combined with dry process reflux and flue gas circulating fluidized bed desulfurization technology in the furnace for units with desulfurization efficiency requirements of no more than 70% - 80%, and the investment / benefit ratio is also very attractive.