The dust bag is a key part of the operation of the bag filter, usually the cylindrical filter bag is hung vertically in the dust collector. The fabric and design of the dust bag should be as efficient as possible, easy to peel off dust, and durable. The selection of dust bag is very important, it directly affects the dust removal effect of the dust collector, and the selection of dust bag is selected from the following aspects: gas temperature, humidity and chemistry, particle size, dust concentration, filtration wind speed, dust removal method and other factors. The choice of filter media should be based on the temperature, humidity and chemical characteristics of the gas. Factors such as the size, weight, shape, dust concentration, filtration speed, emission concentration of ash cleaning method and working system of bag filter are comprehensively considered.