Abstract: In order to efficiently develop and utilize No.640 complex refractory fluorite ore resources of Xiangzhen Mining，in view of the refractory characteristics of fluorite ore，such as high dolomite con⁃ tent，high sulfur content and fine particle dissemination，the whole process industrial practice research is carried out by means of detection method correction，fluid mechanics optimization of flotation equipment， reagent system adjustment and dynamic regulation of circulating water.The results show that the traditional EDTA titration method is affected by the dissolution kinetics of dolomite，and there is a positive deviation of 4.9%~13.4% in the determination of raw ore and tailings grade. The method of fluoride determination by ion selective electrode can more accurately reflect the actual properties of ore.Aiming at the problems of in⁃ sufficient suction capacity of self-priming flotation machine and decline of separation index after capacity expansion，the collision probability between bubbles in the tank and particles is improved by adding auxil⁃ iary aeration and implementing false bottom transformation，so that the actual recovery rate of the system is stabilized above 74%.In the aspect of reagent system，the multi-stage inhibition system of acidified water glass + KA + FD is constructed，and the combination collector of A6+ oleic acid ester（7.7% emulsifica⁃ tion）is used to alleviate the competitive adsorption problem under the condition of high content dolomite with the help of interface synergy.Further research finds that when the concentration of Ca2+ in the circulat⁃ ing water exceeds 400 mg/L，the consumption of the collector can be significantly increased，and the“fall⁃ ing tank”of the cleaning process can be induced. The industrial application results show that the unit con⁃ sumption of collector can be reduced from 6.16 kg/t to 1.86 kg/t by using the comprehensive process of wa⁃ ter control first-precise detection-enhanced aeration-reagent emulsification，which realizes the efficient and stable separation of high dolomite refractory fluorite ore.

Key words: fluorite, dolomite, fluid mechanics transformation, combined collector, circulating water treatment