Experimental Study on Mineral Processing and Purification of a Quartzite Ore in Gansu

The beneficiation experiments of a quartzite ore in Gansu province were carried out. Based on the process mineralogy study of the raw ore, the different technological processes such as magnetic separation, scrubbing and flotation on the removal of iron impurities in quartzite ore were studied. The purification effect of "magnetic separation-scrubbing" and "magnetic separation-flotation" process was compared. The results showed that the process of "grinding-magnetic separation-flotation" was more conducive to purification for the quartzite ore with SiO₂ of 99.42%, Al₂O₃ of 2 400 μg/g and Fe₂O₃ of 1 814 μg/g. After iron ball milling, the sample was subject to three-stage magnetic separation to remove iron under the magnetic induction intensity of 1.4 T. Then the reverse flotation test was carried out with H₂SO₄ as the regulator, pine oil as frother and PSK-78 sodium petroleum sulfonate as the collector. Finally, the quartz concentrate with SiO₂ content of 99.61%, Fe₂O₃ content of 185 μg/g and recovery of 51.34% was obtained. The process has remarkable iron removal effect and little pollution, and it can greatly improve the added value of products and has a good application prospect.