Abstract: In order to realize the automation，intelligence and precision control of flotation dosing system in a fluorite mine，an intelligent dosing system based on programmable logic controller（PLC）， screw metering pump，ultrasonic flowmeter and servo driver is designed and developed to solve the prob⁃ lems of low dosing accuracy，poor stability and large dosage consumption of traditional scoop-type dosing machine in flotation process. The system uses a screw metering pump as the core execution unit to cope with the transportation challenges of high-viscosity reagents such as oleic acid. The real-time flow monitor⁃ ing is performed by an ultrasonic flowmeter，and a“perception-decision-execution”closed-loop control loop is formed by a servo driver and a PLC to achieve accurate，stable and automated addition of various flotation reagents such as collectors and inhibitors. The industrial test results show that the new dosing sys⁃ tem significantly improves the dosing accuracy，reduces the fluctuation range of reagent consumption from ± 16% of the traditional dosing method to ± 1.47%，and reduces the unit consumption of oleic acid by 33.7%. The fluctuation range of fluorite concentrate grade is reduced from 1.5% to less than 0.7%，and the recovery rate of fluorite is increased by 3.7 percentage points. The annual new addition direct economic benefit is about 4.7 million yuan. At the same time，the labor intensity of personnel is reduced and the working environment is improved. It provides an efficient and reliable technical solution for the intelligent upgrading and fine production of fluorite and similar non-metallic concentrators.

Key words: fluorite flotation, automatic dosing, screw metering pump, programmable logic control? ler , ultrasonic flowmeter, servo driver