Quartz sand beneficiation and purification process

The quartz sand is white dense block, and its main component is quartz, with a content of more than 96%, followed by a small amount of hematite, limonite, ilmenite, garnet, trace montmorillonite, hydrobiotite, etc. Through the analysis of ore dressing experiments, the quartz sand beneficiation plant is finally designed: raw ore - coarse crushing - hand selection - fine crushing - classification - magnetic separation - flotation - acid leaching - washing - dehydration - drying process.

Quartz sand beneficiation and purification process

1. Quartz sand crushing process

This stage mainly includes crushing-hand-selection and fine crushing links, in which the jaw crusher is used in the coarse crushing stage, and the crushed products are sent to the next link by a belt conveyor. Qualified quartz sand ores are selected, and the minerals after hand-selection will enter the roller crusher for fine crushing. The material enters the grinding and grading link.

2. Quartz sand magnetic separation process

Dry magnetic separator is used for primary separation, mainly to remove garnet, hematite, limonite, ilmenite and their associated particles. The equipment adopts a dry roller magnetic separator with a magnetic field strength of 5000-11000Oe. After magnetic separation, the grade of +40 mesh SiO2 can reach 99.05%, and the content of Fe2O3 is 0.071%; 40-80 mesh SiO2 is 99.09%, and Fe2O3 Content 0.070%; 80-140 mesh SiO2 grade 99.14%, Fe2O3 content 0.067%; 140-200 mesh SiO2 grade 99.10%, Fe2O3 content 0.069%.

3. Quartz sand flotation process

The flotation process is mainly to remove mica and Fe2O3 in quartz, using XFb single-cell flotation machine, using H2SO4 as regulator, pH=2.5~3, sodium petroleum sulfonate as collector, terpineol oil as foaming agent, Quartz is obtained by flotation. After flotation, about 70% of mica can be removed, and the content of Fe2O3 can be reduced to less than 0.013%.

4. Quartz sand acid leaching process

Its purpose is mainly to remove the harmful components in the quartz particles after flotation (all of which are conjoined on the surface in the form of spots or inclusions). HCl, HNO3, H2SO4 and HF can be used, among which H2SO4, aqua regia and HF The effect of removing Ti is better.

5. Quartz sand washing process

After acid leaching, the surface of quartz sand has dissolved soluble impurity residual liquid adhered to it, which needs to be removed by washing. The washing process is a process of diffusing the impurity compounds and residual liquid on the quartz surface to the liquid phase. For washing after acid leaching I, use tap water (washing 3 times); for washing after acid leaching II, wash with tap water first, and then wash with deionized water 3 times when the washing liquid is close to neutral.

6. Quartz sand dehydration process

The washed quartz sand solution is sent to the concentrator for concentration and dehydration, and the dehydrated product is pumped into the filter press for secondary dehydration. The final filter cake with a water content of less than 20% can be sent to the tailings pond for storage.

7. Quartz sand drying process

Dry at 120°C for 15-20 minutes to obtain the final high-purity quartz sand.