Preconcentrating Ultrafine Ilmenite Tailings Using a Laboratory-Scale Reflux Classifier

China is rich in reserves of titanium, but a large amount of titanium resources is lost in the ultrafine tailings, and it is challenging to treat the ilmenite contained in ultrafine ore. The reflux classifier (RC), a novel gravity concentration technology, has been applied in the preconcentration of ultrafine ilmenite in this study. During this process, the feasibility of using RC for preconcentration of ultrafine ilmenite was explored through theory and conditional experiments. After one-stage preconcentration using RC, the ultrafine ilmenite ore with a TiO2 grade of 8.77% can be concentrated into a product with a TiO2 grade of 20.3% and a recovery rate of 82.8%. The tailings grade is as low as 2.44%, and the yield reaches 62.6%. The separation efficiency achieves 50.0%. Experimental results demonstrate that utilizing RC for the preconcentration of ultrafine ilmenite can avoid the influence of weakly magnetic gangue and achieve better results compared to a magnetic separator. Therefore, RC offers a more effective and affordable method for preconcentrating ultrafine ilmenite ore.