There are usually two ways to solve the problem of dust removal and desulfurization of coal-fired boilers. One is to change the fuel of the boiler and replace the coal-fired boiler with oil, gas or other forms of boilers. This measure will reduce the generation of smoke and sulfur dioxide, but the investment cost is large, and the price of other fuels is often higher than the price of coal. If the additional production cost is used in some enterprises with poor benefits, it may not be implemented. It may not be implemented. Another way is to install dust removal and desulfurization equipment before the boiler flue gas is discharged to the chimney. For most medium and small boilers, they are generally equipped with cyclone, multi-tube or water film dust removal equipment, but the desulfurization problem is rarely considered. The semi-dry boiler flue gas dust removal and desulfurization device is between the dry method and the wet method. It combines the advantages of high reaction rate and good dust removal effect of the wet method with the advantages of simple post-treatment of the dry method and avoidance of secondary pollution to achieve integrated dust removal and desulfurization.