How to improve the poor iron removal effect of quartz sand?

As an important industrial raw material, the purity of quartz sand directly affects the quality of the final product. Iron removal is one of the key links in quartz sand purification, but in actual production, the iron removal effect is often unsatisfactory. In the above, we focused on several factors that affect the iron removal of quartz sand. In this article, I will propose targeted solutions around these factors. The solution is mainly reflected in process optimization, data control, and technological innovation.

011. Optimization of quartz sand beneficiation process

Crushing and grinding optimization: Determine the appropriate crushing and grinding process parameters through experiments, and adopt a combination of multi-stage crushing and fine grinding to ensure the full dissociation of iron minerals while avoiding the occurrence of over-crushing. Innovative grinding equipment can be introduced, such as high-efficiency ball mills, stirred mills, sand mills, etc., to improve grinding efficiency and dissociation.

Improvement of sorting process: According to the characteristics of iron minerals in quartz sand, reasonably select magnetic separation equipment and parameters. For quartz sand containing weakly magnetic iron minerals, a high gradient magnetic separator is used, and parameters such as magnetic field strength and feeding speed are optimized. In the flotation process, high-efficiency and highly selective collectors are developed and selected, and the pH value is accurately controlled, and a complete pH adjustment and monitoring system is established to ensure that the flotation process is carried out under reasonable conditions.

Upgrade of pickling process: a composite acid system is used, such as a combination of 4% HCl + 2% oxalic acid, to improve the solubility of iron impurities in different forms. Strictly control the pickling temperature and time, raise the temperature to 70°C, extend the reaction time to 4h, and strengthen stirring to improve mass transfer efficiency and ensure that the acid and quartz sand are fully in contact and react.

022. Key parameter control of quartz sand beneficiation

Magnetic separation: Increase the background magnetic field strength to ≥1.2T to ensure that various magnetic iron minerals can be effectively captured. At the same time, control the slurry flow rate to ≤0.2m/s, so that the iron minerals have enough time to interact with the magnetic field and improve the magnetic separation efficiency.

Pickling: A composite acid system is used to prepare the acid solution strictly according to the ratio of 4% HCl + 2% oxalic acid. During the pickling process, the temperature is stably controlled at 70°C and the reaction time is maintained for 4 hours. The iron dissolution rate is improved through precise temperature and time control.

033. Innovation in quartz sand beneficiation technology

Microwave-assisted acid leaching: Introducing microwave-assisted acid leaching technology, using the high-frequency radiation of microwaves to accelerate the reaction rate between acid and iron minerals and improve the iron dissolution rate. Studies have shown that this technology can increase the iron dissolution rate by 15-20%, while shortening the pickling time and reducing energy consumption.

Biological iron removal: Explore biological iron removal technology, using microorganisms such as Thiobacillus ferrooxidans to oxidize iron minerals to separate iron from quartz sand. This method has the advantages of low cost and environmental friendliness, which can reduce production costs by about 30%. It is one of the important development directions for quartz sand iron removal in the future.

There are many reasons why quartz sand has poor iron removal effect, most of which are caused by multiple factors. The above-mentioned optimization schemes can effectively improve the iron removal effect of quartz sand and meet the demand for high-purity quartz sand in industrial production. However, in actual production, enterprises should look for manufacturers that can provide high-efficiency mineral processing technology solutions and high-quality mineral processing equipment according to their own raw materials and process characteristics to improve the problem of low iron removal efficiency of quartz sand.

Xinhai has rich experience in quartz sand ore dressing, purification, iron removal and impurity removal. It can design quartz sand ore dressing schemes for different purity ore dressing, provide mineral processing equipment and subsequent project management and operation services. It has completed several quartz sand ore dressing general engineering projects, including the 1200t/d quartz sand ore dressing project in South Korea, the 2000t/d silica sand beneficiation plant project in Japan, and the 1000tpd quartz stone ore dressing project in Mingguang Jiabao, Anhui, all of which have achieved ideal purification indicators.