High-purity quartz sand is derived from natural crystal, silica, and quartzite through meticulous selection and fine processing. It has diverse applications, such as manufacturing various types of glass, serving as a water treatment filter material, or being used as a base material in ceramics and refractory porcelain.
The beneficiation process for quartz sand primarily focuses on impurity removal and purification, aiming to eliminate minor or trace impurities and produce refined or high-purity quartz sand through advanced separation techniques. Key steps in this process include analyzing and removing impurities from the quartz sand, followed by a comprehensive purification procedure. The general process flow is as follows:
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.
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 primarily used for the coarse crushing of quartzite, while the impact crusher handles fine crushing. In the production of high-purity quartz sand, the sand-making machine excels in both fine crushing and shaping, making it the ideal equipment for producing high-quality, high-purity quartz sand.
Qualified sand and gravel are separated using a circular vibrating screen. Quartz sand particles smaller than 1mm are sent to a sand washing machine to remove stone powder and dust, while particles larger than 6mm are returned to the crushing system for further processing with an impact crusher or sand-making machine. This screening and cleaning system works in conjunction with the crushing system, creating a seamless closed-circuit cycle.
Following process standards, accepted sand and gravel are placed in a cleaning tank, where clean water is used to wash away dirt and impurities from the ore surface. Operators must wear clean protective water boots during this stage to maintain safety and hygiene.
Quartz sand is ground in a ball mill for beneficiation and impurity removal, producing high-purity quartz powder.
Utilizing a magnetic separator, magnetic force is applied to sort out iron and other strong or weak magnetic substances from the quartz sand, aiding in impurity removal.
Quartz sand is soaked in a mixture of HCl and HF acid for six days, targeting the removal of acid-soluble metal oxides and specific silicate minerals. Acid leaching is a critical step in purifying high-purity quartz sand and is essential when preparing quartz glass for electric light sources or quartz materials for photovoltaic and semiconductor devices.
By exploiting the differences in physical and chemical properties on the surface of mineral particles, flotation selectively removes impurities like mica, feldspar, and iron-bearing minerals from quartz sand.
A shaking table combined with controlled water flow enables gravity separation, effectively reducing the mica content in quartz sand.
