In this paper, the processing of photovoltaic glass ultra silica sand is introduced in detail. The Fe2O3 in silica sand is reduced to less than 90ppm by flotation with common quartz sand as raw material to meet the quality requirements of photovoltaic glass raw materials.
Ultra white glass requires Fe2O3 < 0.009% in its composition, which has high light transmittance. The light transmittance determines the quality of glass. The light transmittance of float glass is 86%, and the light transmittance of ultra white glass is more than 92%. The glass substrate of solar photovoltaic power generation system needs to use ultra white glass.
The production of ultra white glass requires very strict quartz sand, SiO2 > 99.6%, Fe2O3 < 0.005% - 0.001%, otherwise the quality of ultra white glass cannot be guaranteed. With the development of photovoltaic power generation, the demand for ultra white glass has multiplied, and the demand for high-purity and low-iron quartz sand has also increased. Acid washed quartz sand was used for high-purity and low-iron quartz sand before. However, the storage of quartz in China is small, mining is difficult, processing cost is high, and output is low, which is far from meeting the demand of photovoltaic industry.
This silica sand processing
provides a quartz sand flotation
process, which can promote the production of quartz sand and ensure the quality of products, so as to solve the problem that the production of quartz sand in our country can not meet the growing market demand at present.
The specific technical scheme of sililca sand flotation processing is as follows:
The quartz sand raw material is put into the production bin, and then the quartz sand raw material is put into the first conditioning tank
for mixing. A permanent magnet is placed outside the conditioning tank. Before the quartz sand raw material is put into the first conditioning tank, the iron is removed by the permanent magnet for the first time; 45% H2SO4 solution or 4-5% H2SO4 and HF solution are added into the first conditioning tank, and the PH value is adjusted to 3. The quartz sand raw material is put into the conditioning tank to form slurry. Then the quartz sand slurry is fed into the second conditioning tank, and the flotation agent is added into the second conditioning tank for mixing.
The composition of flotation reagents is as follows:
Fatty alkyl propylene diamine 30-35%
Butyl xanthate 3-4.5%
Fatty acids 30-35%
Terpineol oil 0.1-0.3%
Quartz sand slurry and flotation agent react fully in the second conditioning tank.
Then the quartz sand slurry is put into the flotation machine
for flotation, and the flotation quartz sand concentrate is screened by high-frequency vibrating screen and then flows into the fine sand tank, and then the slurry of the fine sand tank is pumped into the desliming cone
or spiral ore washing machine
by the slurry pump to remove a large amount of water containing agent from the quartz sand concentrate, and then it is put into another desliming cone, and then it is rinsed by adding clear water, and then it is washed again by the permanent magnet high gradient strong magnetic separator After iron removal, it is sent to the fine sand removal reservoir.
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, thus improving the production efficiency of quartz sand, greatly reducing the production cost of quartz sand and reducing the labor intensity of operators.
Note: flotation is a cheap method to reduce the iron content of quartz sand, which is suitable for the iron reduction and purification of most quartz sand.