Ultrafine Silica Sand Beneficiation Process

01Ultrafine silica sand pretreatment process

Due to the presence of iron in the raw ore, the iron ore content of the raw ore can be controlled through the elutriation process. In order to meet production needs, a magnetic rod iron removal device can be installed in the simple sand washing line. The titanium in the raw ore needs to be removed through spiral chute gravity separation. The content of kaolin and fine sand in the raw ore is high, and the content of coarse sand is low, resulting in the overall small particle size of the raw ore. The difficulty of this process is the separation of fine sand and kaolin.

02Ultrafine silica sand separation of kaolin

When separating kaolin, the process flow used is: spiral classifier + scraper secondary overflow separation.

Working principle of the sinking spiral classifier: The spiral classifier equipment mainly relies on the principle that the size and specific gravity of solid particles are different, and the settling speed in the liquid is different. The fine-grained ore will float in the water and become the overflow part, while the coarse-grained ore will sink to the bottom of the tank and be pushed to the upper part by the spiral and discharged. This equipment is mainly mechanical grading. When the spiral classifier is running, the spiral rotates at low speed, which can stir the slurry and make the fine particles suspended on it. The fine particles overflow when reaching the overflow dam, and the coarse-grained ores sink to the bottom of the tank, and are then conveyed by a screw to the discharge port and discharged as return sand.

Working principle of the scraper: This process uses a semi-buried scraper. The equipment is equipped with a chain that circulates in a tilted water tank, and scrapers are evenly spaced on the chain. The attachments on the sand and gravel are separated from the sand and gravel through the action of water. As the chain circulates, the attachments float upward, and the sand and gravel fall from top to bottom, and are transferred from the scraper to the water tank at the lower end, with a scraper. Continuously scrape and wash the gravel. During the entire scraping process, the movement trajectories of attachments and materials are phase separated. Since the scraper is transported by a chain scraper, it can complete the cleaning of sand and gravel below 200mm, and is more suitable for cleaning materials with a lot of attachments. This kind of equipment has the advantages of simple structure, clean cleaning, convenient operation and maintenance, large output, high efficiency, low energy consumption, and a wide range of material particle size range.

After the above process, the kaolin and fine sand in the ultrafine quartz sand can be separated. After the kaolin enters the kaolin slurry pool through the overflow port of the scraper, it can be made into kaolin cake after being dehydrated by a concentrator and a filter press. The kaolin at this time can be sold as raw material for other industries.

03Ultrafine silica sand separates fine sand

After the kaolin is separated, the fine sand needs to be separated using a desludge hopper + hydraulic classifier separation method.

Working principle of the desludging bucket: The desludging bucket consists of a tank body and a wear-resistant pinch valve. The slurry with fine sand enters the desliming bucket from the buffer tank on the upper part of the tank body, and the wear-resistant pinch valve controls the desliming The flow rate at the bottom of the bucket. When the flow rate is controlled at the appropriate position, light particles below 140 mesh overflow through the overflow port on the tank, allowing the slurry that meets the requirements to enter the next process. The desludge bucket has a simple structure, easy operation, no noise, and is easy to configure, install and maintain.

Working principle of hydraulic classifier: During hydraulic classification, the sedimentation speed of mineral particles in water is different, and the mixed particle group with a wide particle size distribution range can be divided into several particle groups with a narrow particle size distribution range. The classification process is also based on the different movement speeds of mineral particles in water. At this time, large and light mineral particles and small and heavy mineral particles settle at the same speed, so they can form a particle size grade. Therefore, hydraulic classification is performed not only by particle size, but also by specific gravity. The hydraulic classifier can sort mineral particles of 25-120 mesh, but the classification effect is poor for particles smaller than 325 mesh.

After the fine sand mortar settles through the desludging hopper, the high-concentration slurry at the bottom of the desludging hopper then enters the hydraulic classifier for classification and settlement, which can separate fine sand above 140 mesh and fine sand below 140 mesh. The separated fine sand enters the fine sand dehydration process and then enters the fine sand library. After hydraulic classification, the fine sand is dehydrated and enters the fine sand warehouse for further drying before being sold as finished product.

The above is the beneficiation process of ultra-fine quartz sand, and the process design should be based on the characteristics of the ore itself. Xinhai Mining recommends conducting beneficiation test to determine a suitable quartz beneficiation process plan. Xinhai Mining has many years of experience in quartz sand beneficiation plan design. If necessary, please leave a message for consultation.