Method for preparing high-purity quartz sand from kaolin tailings

Abstract

The invention provides a method for preparing high-purity quartz sand from kaolin tailings. The method comprises the following steps of stirring and scrubbing the kaolin tailings serving as raw ore, and screening to obtain materials with the particle size of +0.6 mm; conducting ore grinding on materials with the particle size of +0.6 mm, conducting grading, conducting magnetic separation operation on mineral aggregates with the particle size of 0.4 mm-0.1 mm to obtain magnetic materials and non-magnetic materials, conducting gravity separation operation on the non-magnetic materials to obtain gravity separation light minerals and gravity separation heavy minerals, and material regrinding operation and screening on the gravity separation light minerals to obtain minerals with the particle size of +0.1 mm ; and conducting flotation operation on the minerals with the particle size of +0.1 mm to obtain flotation concentrate, removing upper water from the flotation concentrate, conducting ultrasonic acid pickling, and screening to obtain coarse materials with the particle size of +0.1 mm, namely the high-purity quartz sand. By means of the method, the high-quality quartz concentrate product can be obtained, the processing time is short, the technological process is simple, energy consumption is low, and the obtained quartz concentrate is high in quality and can meet the quality requirement of high-purity quartz.

Description

technical field [0001] The invention relates to the technical field of kaolin tailings, in particular to a method for preparing high-purity quartz sand from kaolin tailings. Background technique [0002] In recent years, with technological progress and rapid economic development, the demand for quartz resources has increased sharply, not only in the new generation of information technology (optical fiber communication, electronic packaging), new energy (photovoltaic industry), new materials and other strategic emerging industries Wide range of applications, and in precision instruments, optical fiber communications, SiO 2 High-tech industries such as thin-film materials and aerospace and national defense are also more involved. These industries have higher requirements on the purity and particle size of quartz sand, and generally require SiO 2 Content greater than 99.9%, Fe 2 o 3 The content is less than 10μg / g (Fe content is less than 7μg / g), and the particle size requi...

AI Technical Summary

Problems solved by technology

[0010] In short, only grinding, grading, magnetic separation, gravity separation, flotation and other processes are used to purify the existing SiO 2 Low content, Fe 2 o 3 For problems such as high content, only the quality requirements for sand used in the middle and low-end glass industry can be obtained. To further improve the quality of quartz sand products, it is necessary to increase the roasting and acid leaching process. However, the roasting process temperature generally needs to be between 900-1100 ° C. It needs to be used above 50°C, and the leaching time is more than 2 hours. Therefore, although the purity of quartz obtained by the high-temperature roasting-acid leaching process is high, the roasting temperature is high, the energy consumption is large, the acid leaching time is long, and the operation is complicated. higher cost

Therefore, most companies generally only produce SiO 2 Greater than 99.3%, Fe 2 o 3 Sand for photovoltaic glass with a content of less than 80 μg / g, without further processing

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