Hard To Choose Oolitic Iron Ore Beneficiation Process And Mechanism Research

Oolitic iron ores has been deemed to one of the refractory mineral in the mineral processsing area. With the continual depletion of freemilling iron ores, the level of comprehensive utilization of refractory iron ore which are characterized by low grade, fine grain and complicated composition concern the development of iron and steel industry in china. Iron concentrate often containing impurities higher by traditional gravity concentration and magnetic separation. Reverse flotation is an effective method of disposing complex and refractory iron ore currently, superiority of cationic collector play a positive role in reverse flotation of iron ore. Oolitic martite was experiment object, a new-style cationic collector was used on the reverse flotation technology.In this study, common and new-style cationic collector was used in the flotation of pure quartz, pure magnetite and false mixed mine. The investigation indicated that:under the flotation system of QP-113(a new-style cationic collector), when pH was between4and8, the collector showed a better flotability on quartz, but in all pH range, the collector showed a weak flotability on magnetite, the collector also had a strong selectivity on magnetite. The adaptability of the collector was strong to inevitable metal ions. The magnetite was depressed by using sodium lignosulfonate as the depressant of the iron minerals.In the pH=6.0,the dosage of QP-113is3.0×10-1mg/L and the dosage of sodium lignosulfonate is8mg/L, which is the best flotation conditions of the single mineral tests. QP-113was successfully applied to separate quartz from magnetite by reverse flotation. A concentrate with a grade of68.43%TFe and the recovery of96.76%TFe was obtained from a feed with a grade of55.92%TFe and20.42%SiO2.The actual ores is a refractory one due to its complex mineral dissemination particle sizes. Based on its process mineralogy research, through a series o f tests, a process consisting of magnetization roasting-stage grinding-stage low intensity magnetic separation-cationic reverse flotation was adopted for treating this ore. In the best technology conditions, the iron grade is61.30%,the iron recovery is80.43%,showing that the purpose to increase iron grade while reducing silicon content can be efficiently achieved.The interaction mechanism of collector QP-113in flotation of minerals was investigated by the measurements of contact angle, Zeta-potential, adsorption capacity and FTIR-DRIR. The experimental results show that the new-style cationic collectors absorb on the surface of the quartz prior to the surface of magnetite, and change the contact angles and the Zeta-potentials of quartz apperantly than the magnetite. The adsorption capacity of magnetite is less than quartz, the change of contact angle and Zeta-potential was also less. In the neutral pH, the adsorption of collector was strong on the surface of quartz. In all pH range, the adsorption of collector was feeblish on the surface of magnetite. QP-113showed the differences of adsorbability apperantly on the surface of the minerals. The results of FT-IR measurements also proved that the adsorption of collector on the surface of minerals is reversible, physical type because there was no new products on the surface of the minerals.