High purity quartz sand is a kind of stone made of natural crystal stone, silica and quartzite through careful selection and fine processing. It can be used to make all kinds of glass, as water treatment filter material, or as embryo and shaft material of ceramics and refractory porcelain. After years of experience, Fodamon engineers summarized and refined that the production process of high-purity quartz sand includes beneficiation, crushing, screening, cleaning, grinding, impurity removal, drying and packaging.
The beneficiation process of quartz sand is mainly to remove impurities and purify, remove a small amount or trace impurities in quartz sand, and obtain a highly difficult separation technology of refined quartz sand or high-purity quartz sand. Quartz sand process mainly includes quartz sand impurity analysis and impurity removal process, quartz sand purification process, etc. The process flow is roughly as follows:
01 Beneficiation
High purity quartz sand is generally made of silica, quartzite or natural crystal. The raw materials are crushed, sorted and sorted manually and put into the silo.
02 Crushing
Jaw crusher, impact crusher and sand making machine are generally used for crushing operation. Quartzite is continuously and evenly sent into jaw crusher by vibrating feeder for coarse crushing, and the coarse broken quartzite is sent to sand making machine for fine crushing by belt conveyor.
The jaw crusher is mainly used for the coarse crushing of quartzite, and the impact crusher is used for the fine crushing. The sand making machine gives full play to the fine crushing and shaping role in the production process of high-purity quartz sand. It is the most ideal high-purity quartz sand crushing equipment.
03 Screening
Qualified sand and stone are screened out by circular vibrating screen. Quartz sand with particle size less than 1mm is sent to the sand washing machine to clean stone powder and dust. Quartz sand with particle size more than 6mm is sent back to the crushing system and re crushed by impact crusher or sand making machine. The screening cleaning system and crushing system form a tight and ingenious closed-circuit cycle.
04 Cleaning
Put the accepted sand and gravel into the cleaning tank according to the process standard, remove the dirt with clean water and wash away the impurities attached to the ore surface. Operators must wear clean protective water boots during cleaning.
05 Grinding
The quartz sand is ground by ball mill for beneficiation and impurity removal to produce high-purity quartz powder.
06 Impurity Removal
(1) Magnetic separation
By using the magnetic difference of various ores or materials and sorting under the action of magnetic force by magnetic separator, the iron strong magnetic substances contained in quartz sand and weak magnetic substances can be removed.
(2) Acid leaching
A certain proportion of HCl and HF mixed acid is used for soaking for 6 days, mainly to remove acid soluble metal oxides and some silicate minerals. Acid leaching is one of the important processes in the purification process of high-purity quartz sand. Acid leaching must be used in the preparation of quartz glass for electric light source and quartz raw materials for photovoltaic and semiconductor devices.
(3) Flotation
According to the different physical and chemical properties on the surface of mineral particles and the difference of mineral floatability, flotation is mainly used to remove the impurities of mica, feldspar and iron bearing minerals in quartz sand.
(4) Reselection
The use of shaking table and appropriate water flow gravity separation can effectively reduce the mica content.