High-purity quartz refers to quartz sand with a SiO2 content of 99.92% to 99.99%, and the generally required purity is above 99.99%. It is the raw material for the production of high-end quartz products. Because its products have excellent physical and chemical properties such as high temperature resistance, corrosion resistance, low thermal expansion, high insulation and light transmission, they are widely used in optical fiber communication, solar photovoltaic, aerospace, electronics and The strategic position of high-tech industries such as semiconductors is very important.
In addition to the main mineral quartz, quartz raw materials are usually accompanied by impurity minerals such as feldspar, mica, clay and iron. The purpose of beneficiation and purification is to adopt appropriate beneficiation methods and technological processes to improve product purity and reduce impurity content according to different product requirements for particle size and impurity content. The beneficiation and purification of quartz sand depends on the content of impurities such as Al2O3, Fe2O3, Ti, Cr, etc., the state of occurrence, and the requirements for product particle size.
It is generally believed that everything except silicon oxide is impurities, so the purification process of quartz is to increase the content of silicon dioxide in the product as much as possible, while reducing the content of other impurity components.
At present, the traditional quartz purification processes that are maturely used in the industry include sorting, scrubbing, calcination-water quenching, grinding, screening, magnetic separation, gravity separation, flotation, acid leaching, high temperature degassing, etc. The deep purification process includes chlorine Chemical roasting, radiation color sorting, superconducting magnetic sorting, high temperature vacuum, etc.
The iron-containing impurities and aluminum-containing impurities in the quartz raw materials are considered to be the main harmful impurities. Therefore, the progress and development of the purification methods and technological processes of the quartz raw materials are mainly reflected in the effective removal of iron-containing impurities and aluminum-containing impurities.
The high-performance quartz glass products prepared from high-purity quartz sand are the basic raw materials for the production of optical fibers and attached optoelectronic components for the communications industry, and are used to produce single-mode and multi-mode optical fiber preforms and quartz sleeves. Devices made of quartz glass materials are particularly widely used, such as: quartz diffusion tubes, large diffusion bell jars, quartz cleaning tanks, quartz furnace doors and other products.
High-precision microscopic optical instruments, high-definition, high-transmittance optical lenses, excimer laser optical devices, projectors and other advanced optical instruments are all made with high-purity quartz as the basic raw material.
High-purity quartz is the basic raw material for the production of high-temperature resistant quartz lamps. It is commonly used to produce high-performance, high-temperature resistant lamps, such as ultraviolet lamps, high-temperature mercury lamps, xenon lamps, halogen lamps, and high-intensity gas discharge lamps.