Quartz Sand Processing

Quartz sand beneficiation is a complex technology aimed at removing trace impurities from quartz sand to produce a high-grade product or high-purity quartz sand. The beneficiation process primarily involves washing, classification, sizing, desliming, scrubbing, magnetic separation, flotation, acid leaching, and microbiological leaching. These methods are employed to enhance the quality and purity of quartz sand for various industrial applications.

Dry, Sized, Beneficiated High-Purity Quartz Sand

Process Flowchart

Washing, Classification, and Sizing (Desliming): By reducing the particle size of quartz, the grade of quartz decreases, while the impurity grade increases. This phenomenon is particularly noticeable in quartz sand containing a significant amount of clay minerals.

Scrubbing: This stage aims to remove thin layers of iron and argillaceous impurities present on the surface of quartz sand using mechanical force, crushing force, inter-particle forces between the sand grains, and further abrasion of undeveloped aggregates. There are mainly two scrubbing methods: frictional scrubbing and mechanical scrubbing.

Flotation: Typically, two flotation methods using anionic collectors in acidic conditions or anionic-cationic collectors in alkaline conditions can achieve good results. Generally, after scrubbing, desliming, magnetic separation, and flotation, the grade of quartz sand can reach over 99%, meeting the requirements for industrial sand.

Acid Leaching: Dilute acid has a significant effect in removing iron and aluminum, while the removal of titanium and chromium is carried out using relatively concentrated sulfuric acid leaching. A combination of these acids is typically used for leaching impurities. The control of various leaching factors should be based on the final quartz grade. Additionally, the concentration, temperature, and amount of acid should be minimized to reduce the cost of quartz beneficiation.

Magnetic Separation: The use of strong magnetic separators to remove iron impurities from quartz is crucial. For quartz sand processing plants requiring high-quality quartz sand, weak magnetic impurities can be effectively removed under the influence of a strong magnetic field. In recent years, strong magnetic separators have been widely used in quartz sand processing plants.