Silica Sand Flotation Processing Photovoltaic Glass

This paper introduces the processing technology of super silica sand for photovoltaic glass in detail. Using ordinary quartz sand as raw material, Fe2O3 in silica sand is reduced to below 90ppm through flotation, which meets the quality requirements of photovoltaic glass raw materials.

Ultra-clear glass requires Fe2O3<0.009% in its composition and high light transmittance. Light transmittance determines the quality of glass. The light transmittance of float glass is 86%, and the light transmittance of ultra-clear glass is more than 92%. The glass substrate of the solar photovoltaic power generation system needs to use ultra-clear glass.

The production of ultra-clear glass has very strict requirements on quartz sand, SiO2>99.6%, Fe2O3<0.005%-0.001%, otherwise the quality of ultra-clear glass cannot be guaranteed. With the development of photovoltaic power generation, the demand for ultra-white glass has doubled, and the demand for high-purity low-iron quartz sand has also increased. Pickling quartz sand was previously used for high-purity low-iron quartz sand. However, my country's quartz reserves are small, mining is difficult, processing costs are high, and output is low, which is far from meeting the needs of the photovoltaic industry.

This silica sand treatment provides a quartz sand flotation process, which can promote the production of quartz sand and ensure product quality, thereby solving the problem that the current production of quartz sand in my country cannot meet the growing market demand.

The specific technical scheme of silica sand flotation processing is as follows:

Put the quartz sand raw material into the production bin, and then put the quartz sand raw material into the first conditioning tank for mixing. A permanent magnet is placed outside the regulating tank. Before the quartz sand raw material enters the first tempering tank, iron is removed by the permanent magnet for the first time; 45% H2SO4 solution or 4-5% H2SO4 and HF solution is added to the first regulating tank, and the pH value is adjusted to 3 . Put the quartz sand raw material into the regulating tank to form the slurry. Then the quartz sand slurry is sent to the secondary conditioning tank, and the flotation agent is added to the secondary conditioning tank for mixing.

The composition of the flotation agent is as follows:

Fatty Alkyl Propylene Diamine 30-35%

Butyl xanthate 3-4.5%

Fatty acids 30-35%

Diesel 30-35%

Terpineol oil 0.1-0.3%

Quartz sand pulp and flotation agent fully react in the second regulating tank.

Then put the quartz sand ore slurry into the flotation machine for flotation, the flotation quartz sand concentrate is screened by the high-frequency vibrating screen and then flows into the fine sand tank, and then the pulp in the fine sand tank is pumped into the desliming cone or spiral washing machine A large amount of water-containing agent in the quartz sand concentrate is removed by a slurry pump, then put into another desliming cone, added with clean water to rinse, and then washed again by a permanent magnet high-gradient high-strength magnetic separator to remove iron and sent to fine sand cleaning library.

The flotation process of quartz sand is easy to realize and simple to operate. Through this flotation method and flotation agent, the flotation of quartz sand can be realized quickly and effectively, thereby improving the production efficiency of quartz sand, greatly reducing the production cost of quartz sand, and reducing the labor intensity of operators.