The application fields of phosphorite are growing wider, thus making a constant increase of the demand of phosphorite. In China, phosphorite dressing method is very mature. Although China has a great amount of phosphorite ore resource, there are many lean ore and few rich ore, with relatively complicated ore properties. According to different characteristics, the phosphorite dressing methods can be divided into direct flotation, direct-reverse flotation, double reverse flotation and heavy media hydrocyclone separation, and etc.
(1)Direct Flotation Method
Direct flotation method is appropriate for the separation of silica phosphotite ore. The flow chart is as diagram 1. During direct flotation, inhibitors like Na2SiO3 and are commonly used to inhibit silica and calcium minerals; anion collectors are used to select phosphorite. Ningxia Helanshan mine adopts this method to process raw ore with 8.0% P2O5, which obtains concentrates with grade more than 35% and recovery rate of 83%.
(2)Direct-reverse Flotation Method
Direct-reverse flotation method is suitable for the separation of calcarenaceous phosphorite. The dressing method flow chart is as diagram 2. The inhibitors like Na2SiO3 and Na2CO3 are adopted to inhibit silica and calcium minerals first; then anion collectors are used to separate phosphorite by direct flotation; then H2SO4 or H3PO4 to adjust the slurry PH to 5.5~6 to inhibit phosphate; finally, anion collectors to select carbonate minerals by reverse flotation. Adopting this process, Guizhou Wenfu phorsphorite mine has obtained recovery rate of 91.98% and phosphorite concentrates with grade of 35.17%.
(3)Double Reverse Flotation Method
Double reverse flotation method is suitable for the separation of collophanite hard to process. The dressing method flow chart is as diagram 3. H2SO4 or H3PO4 is first used to inhibit phosphorite minerals by adjusting the slurry PH.; then anion collectors to select carbonas minerals like dolomite by reverse flotation; finally, kation collectors are used to separate silicate minerals by reverse flotation after the slurry is processed by de-sliming.
(4)Heavy Medium Hydrocyclone Separation
Heavy medium hydrocyclone separation is appropriate for the separation of silica and calcium phosphorite ore. The dressing method flow chart is as diagram 4. Using this method, phosphorite concentrates and gauge minerals are separated in accordance with their density differences.
As the enterprise conducting mine EPC service first in China, Shandong Xinhai Mining Technology Equipment Inc. has provided ore dressing turnkey service for more than 500 mines according to the requirement of customers. Besides, as a world-renowned mining machineries manufacturer, Xinhai can supply its customers with excellent crushing, screening, grinding and separating machines, gravity separating machines, magnetic separating machines and flotation machines and so on. With advanced phosphorite dressing technology, equipment and top pre-sales and after-sales services, Xinhai equipment and its EPC service is absolutely worth trusts and cooperation for customers.