Abstract: It introduces the transformation process of 5 000t/d kiln bag filter of CNBM Tianshan Cement Group. Through the comparison and selection , the transformation schemes of increasing the number of filter bags, increasing the filter area and adjusting the length of the bag is determined. Composite P84 membrane filter material is selected as the filter bag material, which has stable performance and high filtration efficiency in acidic waste gas and alkaline dust. After the transformation, it passed the assessment of the environmental protection department and achieved the design goal of low resistance, low emission and low energy consumption.