Single quartz sand production process flow

Single quartz sand production process flow

Quartz sand is an important raw material for making glass, sodium silicate, semiconductors, optical fibers, lasers, and is also an essential material in high-tech fields such as aerospace, atomic energy technology, and military industry. Quartz sand is used in different fields and has different purity requirements. According to purity requirements, the production process of quartz sand can be divided into single quartz sand production process and combined quartz sand production process.

The main purpose of the quartz sand production process is to remove impurities and minerals from it. Among them, the single quartz sand production process is mainly used for pre-treatment or when the impurity content of quartz sand is low and the purification requirements are low. Common single quartz sand production processes include water washing classification desliming, scrubbing, magnetic separation, flotation, and acid leaching production processes.

1. Quartz sand water washing classification desliming production process

The quartz sand water washing and grading desliming process mainly involves washing and desliming quartz sand containing a large amount of clay before selection, which is an essential process before mineral processing. In addition, the grade of silica will decrease with the decrease of quartz particle size, while the grade of impurity minerals such as iron and aluminum will increase accordingly. Before selection, it is also necessary to carry out impurity removal through water washing and grading desliming operations.

2. Quartz sand scrubbing production process

The scrubbing process uses a scrubbing machine to remove thin films of iron and viscous impurities attached to the surface of quartz through the friction between ore particles, and then classifies the washed ore particles to achieve purification. It is usually used in the pre selection stage. There are two commonly used scrubbing processes: stick scrubbing and mechanical scrubbing.
Rod grinding and scrubbing process: In the scrubbing process, an appropriate amount of agent is added to increase the electrostatic repulsion between impurity ore and quartz particle surface, and improve its separation effect.
Mechanical scrubbing process: By adding chemicals (water glass), quartz is separated from impurities (clay minerals, iron).

3. Quartz sand magnetic separation production process

Quartz sand magnetic separation is a process that uses a magnetic separator to separate quartz sand from minerals containing magnetic impurities. Magnetic separation can remove mechanical iron minerals (such as hematite, limonite, pyrite, ilmenite, biotite, etc.) mixed in quartz sand, as well as weak magnetic minerals and impurities in inclusions and disseminated bodies containing iron minerals.

4. Quartz sand flotation production process

The purpose of quartz sand flotation is mainly to remove non-magnetic impurities (feldspar, mica, etc.), and to achieve purification by adding reagents to make its minerals adhere to foam products, and then inhibiting feldspar or mica of quartz minerals through specific reagents. When there are many impurities in the quartz ore and methods such as scrubbing, desliming, and magnetic separation cannot obtain the ideal quartz grade, flotation technology can be used. The common quartz sand flotation production processes are divided into two types: fluorinated flotation and fluorine-free flotation.
Fluorine flotation process: cationic collectors and hydrofluoric acid activators are used for flotation operations within the acidic pH range, but the fluorinated wastewater after flotation has a serious impact on the surrounding environment.
Fluorine free flotation process: removing the hydrofluoric acid activator, utilizing the difference in structural composition between quartz and feldspar, as well as the difference in Zeta potential between the two, by adjusting the mixed collector of anions and cations, feldspar is preferentially flotation to effectively separate the two.

5. Quartz sand acid leaching production process

The acid leaching production process of quartz sand utilizes various acid solvents (such as sulfuric acid, hydrochloric acid, nitric acid, and hydrofluoric acid) to leach out impurities that are soluble in acid, achieving quartz sand separation. The acid leaching process of quartz sand can be divided into two types: single acid leaching and mixed acid leaching.
Single acid leaching process: add quartz sand to a certain concentration of acid solution, heat it to a certain temperature (appropriate heating time), recover the acid solution, wash and dry the quartz sand for recovery.
Mixed acid leaching process: add washed quartz sand minerals to the mixed acid solution, stir and leach at room temperature for about 24 hours, then wash and dry; If heated, stirred, and leached for about 2-6 hours, then washed and dried.