Study on Flotation Process of a Quartz Fluorite Ore in Western Henan

A quartz-type fluorite ore in western Henan contains 41.58% of CaF₂ and 45.76% of SiO₂. The granularity of the inlay is uneven. Part of the fine-grained fluorite is wrapped by quartz and feldspar, which brings certain difficulties to the upgrading of fluorite. A comparative study of process mineralogy, the flotation reagent system and the closed-circuit flotation process was carried out. Under the optimum process conditions, namely the final fineness of coarse grinding was -0.074 mm, the content of 55%, the dosage of pH adjuster sodium carbonate 2000 g/t, and the dosage of gangue inhibitor water glass 900 g/t, combined collectors oxidized paraffin soap + sodium oleate dosage 200+100 g/t, regrind ore fineness of -0.043mm and content 76.89%, use one stage rough grinding, one roughing and second sweeping six times of beneficiation, high-grade medium ore regrind and return to the second-stage beneficiation flotation process, fluorite concentrate with 97.12% CaF₂ and a recovery rate of 91.10% can be obtained. The fluorite flotation at room temperature could be realized with the combined collectors. Compared with the conventional coarse concentrate- regrinding flotation process, the high-grade middlings- regrinding flotation process has improved the grade and recovery rate of fluorite concentrate. The study of process mineralogy shows that the choice of regrinding location is crucial, and the high-grade middlings- regrinding could avoid over-grinding of dissociated fluorite, increase the degree of dissociation of coprecipitated fluorite, and realize the secondary distribution, which is the key to improve the selection index of this kind of distributed heterogeneous fluorite resources.