What Is Quartz Extraction Process?

01Quartz sand physical extraction method

The physical extraction method of quartz sand is mainly used for the treatment of coarse-grained impurities in quartz sand, mainly including scrubbing method, gravity separation method, magnetic separation method, flotation method, etc.

Scrubbing process

The scrubbing method uses the friction between the machine and the sand to remove the impurity minerals on the surface of the quartz sand, and is generally used for the pretreatment of the quartz ore. At present, it is mainly divided into mechanical scrubbing and rod friction scrubbing. Mechanical scrubbing mainly relies on vigorous movement between blades to rub mineral particles. Due to factors such as mechanical equipment configuration, scrubbing time, and scrubbing concentration, the recovery rate of mechanical scrubbing is about 40%. Different from mechanical scrubbing, in the process of rod friction scrubbing, it is necessary to add chemicals to increase the electric repulsion between impurity minerals and quartz ore particles, so as to achieve a better separation effect. The recovery rate of rod friction scrubbing can reach 80%.

Production equipment: rod mill, high-efficiency stirring scrubber

Magnetic separation process

Magnetic separation is mainly used to remove iron impurities in quartz sand, such as weak magnetic minerals in hematite, limonite and strong magnetic minerals in magnetite.

Generally, a strong magnetic machine with a strength of more than 100000e is used to remove weak magnetic impurity minerals. Strong magnetic impurity minerals are magnetically separated by weak magnetic machine or medium magnetic machine. In addition to the magnetic separation intensity, the number of magnetic separations also has an important impact on the iron removal effect. During magnetic separation, the number of magnetic separations can be increased according to the specific situation, and most of the iron impurities can be removed under the constant magnetic field strength.

Flotation separation process

The flotation method is mainly used to remove natural impurity minerals in quartz sand, such as feldspar, mica and other non-magnetic impurity minerals. There are two types of flotation methods: fluorine flotation and fluorine-free flotation. Based on the protection of the environment, fluorine-free flotation is mostly used. Fluorine-free flotation mainly utilizes the difference in structure and potential between quartz and feldspar, adding a collector to preferentially flotation of feldspar and mica to achieve the separation of the two.

Production equipment: XCF flotation cell machine

02Chemical extraction method of quartz sand

There are two types of chemical extraction methods of quartz sand: acid leaching and complexing. Mainly use inorganic acid and reducing agent, which can achieve better extraction effect. It should be noted that the concentration of acid, temperature, time and washing process, these factors will have an impact on the extraction effect.

Acid leaching method: The acid leaching method uses the characteristics of quartz insoluble in acid to dissolve other impurity minerals with acid solution, so as to realize the separation of quartz from impurities and achieve the extraction effect. Sulfuric acid, hydrochloric acid, nitric acid, and hydrofluoric acid are commonly used acids in acid leaching.

Complexing method: The complexing method mainly uses the organic acid to react with the impurity ions on the surface of the quartz sand after acid leaching to form a stable coordination compound. This can not only prevent the precipitation of impurity ions during the washing process, but also reduce the concentration of impurity ions on the surface of the quartz stone, so that the quartz stone can be further purified.

Production equipment: mixing tank

03Quartz sand microbial extraction method

Quartz sand microbial extraction is a newly developed technology. It mainly uses bacteria, molds and other emblem organisms to remove iron from quartz sand. The results of the study showed that the iron removal effect of Aspergillus niger was obvious. Aspergillus niger produces a bacterial culture of citric and oxalic acids. After the quartz sand is immersed at a certain temperature, the Fe20 content in the quartz sand can be greatly reduced, and the extraction effect is obvious.

The development prospect of the quartz building materials market is broad, the market potential is huge, the demand for raw materials is showing a rising trend, and the economic and social benefits of quartz sand extraction will be further improved. In the actual production process, it is impossible to obtain qualified quartz sand by only one method. Physical methods are often used first, and then other impurities in quartz sand are further removed by chemical methods, so as to achieve qualified extraction standards.