High purity quartz sand generally refers to quartz powder with SiO 2 content higher than 99.99%, which is the main material of quartz glass and quartz crucible. Its high-end products are widely used in large-scale and ultra-large-scale integrated circuits, optical fibers, solar cells, lasers, aerospace, military and other industries.
The quality requirements for quartz sand products are generally directly related to their actual industrial use. If it is used in fine materials and high-performance materials such as electronic materials and quartz crucibles, the quality of raw materials is strict, and high-purity and ultra-pure quartz sand are required, and the total content of impurities is low. Specifically, the quality requirements of quartz sand are mainly reflected in the chemical composition and particle size composition: 1 appearance is white, no visible mechanical impurities; 2 purity requirements: silica content is greater than 99.99%; 3 according to the requirements of different industries, It can be processed into series products of different specifications and models to meet user requirements.
Application of High Purity Quartz Sand
High purity quartz sand is also the main material of quartz glass. Quartz glass is known as "glass mesh" because it has a series of excellent physical and chemical properties, such as high temperature resistance of 1100-1200 ℃, 800 ℃ higher than ordinary glass, transparent refractory, low thermal expansion coefficient of 5.5 x10-7 ℃, equivalent to 1/20 of ordinary glass, which can theoretically expand to zero; Excellent transmittance, ultraviolet, visible, infrared and other can be well transmitted; good electrical insulation, resistivity of 1018Ω/cm at 20℃, insulation strength of 250 kV/cm, vacuum degree of 10-6 Pa; good chemical stability, in addition to hydrofluoric acid, insoluble in any other acids. Quartz glass is a brittle material with good compressive strength, but its tensile strength is lower. Quartz glass is not hydrofluoric acid resistant, and can be transformed into cristobalite at high temperature (over 1000℃). These are two shortcomings of quartz glass.
The main products of quartz glass include high-purity high-temperature resistant quartz glass tubes for large-scale integrated circuits, arc-based quartz crucibles (solar and semiconductor grades), quartz glass for optical communication, and quartz glass for electric light sources. The variety and use of quartz glass are closely related, and users can manufacture different quartz glass according to the characteristics and requirements of quartz glass.
China has made progress in researching ordinary quartz raw materials for quartz glass since the late 1980s. The products studied can reach the level of second, third and fourth grade crystals, but only suitable for medium and low grade quartz glass, high purity and low. The technical difficulties of hydroxy quartz raw materials have not yet been fully overcome. The purity of industrially produced quartz glass raw materials cannot meet the requirements of high-purity quartz sand glass raw materials. The high-quality quartz glass raw materials are mainly imported, which restricts the development of China's quartz sand glass industry, which has caused domestic quartz glass and raw material production enterprises and Concerns from relevant research institutes.
With the depletion of high-quality crystal resources, solving the problem of insufficient self-sufficiency of high-grade quartz sand in China mainly focuses on the improvement of professional technology such as geological prospecting, process mineralogy and mineral processing. First of all, we should look for ores with pure crystals, homogeneous replacement and less gas-liquid inclusions. Secondly, we should develop efficient and stable high-purity quartz mineral processing technology by using modern advanced physical and chemical mineral processing technology and equipment. High purity quartz raw sand has become a strategic product of the national economy.
Engineer Wang, who with a senior engineer title from Fodamon
believes. Efforts to seek the advancement of China's high-purity quartz sand ore purification technology and industrial development, to achieve high-grade (high-purity and ultra-high purity) quartz sand self-sufficiency is urgently needed for the development of China's quartz glass industry, for China's relevant high-tech industries Development is important.