Water washing, sorting
The SiO2 content in quartz sand decreases as the grain size of quartz decreases, while the quality of mineral impurities increases. This phenomenon is especially noticeable in quartz sand containing a large amount of clay minerals, so it is necessary to wash and remove raw quartz sand ore before sampling.
Washing
Washing is the mechanical force and grinding force between sand particles to remove thin-film iron and clay mineral impurities on the surface of quartz sand and further grind disorganized mineral complexes, then classify the work to achieve the effect of further cleaning quartz sand. Currently, there are mainly two methods: rod friction and mechanical abrasion.
Flotation
Separation of mica and quartz is difficult; using an anionic collector in acidic conditions or a cationic collector in alkaline conditions with two flotation methods can achieve good results. Generally, after washing, dirt removal, magnetic separation, and flotation, the purity of quartz sand can reach more than 99%, mainly to meet the needs of industrial sand.
Acid leaching
Dilute acid has a significant effect on removing iron and aluminum, while the removal of titanium and chromium is carried out using more concentrated sulfuric acid. Acid leaching generally uses mixed acids consisting of the above acids for leaching mineral impurities. Control of various factors in acid leaching should meet the requirements of the final quartz grade, minimizing concentration, temperature, and acid amount to ensure quartz purification at lower enrichment costs.

The technological process flowchart is as follows.

The etching process flowchart is as follows.