Abstract: A 35 000 t/a sodium fluosilicate plant in Three-Ring Branch，Yunnan Yuntianhua International Chemical Co.，Ltd. was completed and put into operation in December 2006.In January 2010，the raw material was changed into Glauber′s salt from brine，and the heat source supply of air flow drying was changed into electric furnace from raw coal combustion in FBC. Since the operation，following problems have appeared:1）low output，only about 50% of the design output；2）over-fine particles in the crystallization process led to difficult centrifugal separation；3）low product yield；4）easy caking；5）product in yellow and green.So far，series transformations on technology and equipment have been carried out by Three-Ring Branch according to the above problems，and the product quality，output，and yield were improved，and the continuous and stable operation was ensured.

Key words: sodium fluosilicate, production plant, technological transformation