1. A quartz sand beneficiation process, wherein after preliminary beneficiation, the raw ore is subjected to screening, desliming, scrubbing, and classification to produce a quartz sand product with a silicon content higher than 96%, an iron content lower than 0.15%, and a particle size ranging from 20–24 mesh to 100–130 mesh, characterized in that: the preliminarily beneficiated raw ore flows into two or more layers of screen meshes for two or more screening operations, and the screen meshes are arranged from coarse to fine in the order from top to bottom.
2. The quartz sand beneficiation process according to claim 1, characterized in that: the uppermost screen mesh is a 20–24 mesh screen, which removes coarse sand with a particle size larger than 20–24 mesh; the lowermost screen mesh is a 100–130 mesh screen, which removes fine sand with a particle size smaller than 100–130 mesh; and the sand with particle sizes between 20–24 mesh and 100–130 mesh is collected and passes through a channel to the desliming process.
3. The quartz sand beneficiation process according to claim 1, characterized in that: the screen meshes used in the screening process may be vibrating screens, trommel screens, or other types of screens with different modes of motion.

石英砂の選鉱プロセス

技術分野

The present invention relates to a quartz sand beneficiation process, in particular to a quartz sand beneficiation process using multi‑layer screening meshes for screening.

背景アート

High‑grade high‑quality quartz sand is the main raw material for producing glass. In particular, quartz sand for manufacturing white glass requires high silicon content and extremely low iron content. High iron content will cause the white glass to turn blue and form bubbles, affecting glass quality. In the raw ore, most of the sand with high iron content is concentrated in the fine sand with a particle size below 100–130 mesh. In the traditional process, after preliminary beneficiation, the raw ore is subjected to screening, desliming, scrubbing, and classification to produce finished sand. The screening process usually uses a single‑layer screen mesh for one‑time screening, which cannot remove the fine sand below 100–130 mesh, resulting in persistently high iron content in the finished sand and affecting the quality of white glass. For this reason, improvements have been made on the basis of the traditional process: after preliminary beneficiation of the raw ore, through screening, desliming, and multiple scrubbing operations, electronic iron removal is added to remove iron impurities, thereby improving the grade of the finished sand to meet the production requirements of white glass. However, the above process has disadvantages such as large investment, high cost, and inconvenient maintenance.

発明の概要

The object of the present invention is to overcome the above deficiencies of the prior art and to provide a quartz sand beneficiation process with low investment, low cost, convenient maintenance, and good finished sand quality.

The object of the present invention is achieved as follows: A quartz sand beneficiation process, wherein after preliminary beneficiation of the raw ore, through screening, desliming, scrubbing, and classification, a quartz sand product is produced with a silicon content higher than 96%, an iron content lower than 0.15%, and a particle size ranging from 20–24 mesh to 100–130 mesh. The preliminarily beneficiated raw ore flows into two or more layers of screen meshes for two or more screening operations. The screen meshes are arranged from coarse to fine in the order from top to bottom. The uppermost screen mesh is a 20–24 mesh screen, which removes coarse sand with a particle size larger than 20–24 mesh. The lowermost screen mesh is a 100–130 mesh screen, which removes fine sand with a particle size smaller than 100–130 mesh. The sand with particle sizes between 20–24 mesh and 100–130 mesh is collected and passes through a channel to the desliming process. The screening meshes used in the screening process may be vibrating screens, trommel screens, or other types of screens with different modes of motion.

In the quartz sand beneficiation process of the present invention, since two or more layers of screen meshes are used for screening, the screen meshes are arranged in layers from top to bottom. Under the action of water flow, the preliminarily beneficiated raw ore first flows through the uppermost screen mesh, then continuously falls under gravity, sequentially passing through the lower screen meshes down to the lowermost screen mesh, undergoing multiple screening operations. The uppermost 20–24 mesh screen removes coarse sand larger than 20–24 mesh, and the lowermost 100–130 mesh screen removes fine sand smaller than 100–130 mesh. Since a large amount of iron impurities are concentrated in the fine sand with a particle size smaller than 100–130 mesh, removing the fine sand smaller than 100–130 mesh reduces the iron content of the sand. Other impurities are concentrated in the coarse sand larger than 20–24 mesh, so removing the coarse sand larger than 20–24 mesh increases the silicon content of the sand. The finished quartz sand thus has a particle size between 20–24 mesh and 100–130 mesh, with a silicon content higher than 96% and an iron content lower than 0.15%, meeting the production requirements of white glass and preventing the white glass from turning blue or forming bubbles. When a certain screen mesh is damaged, it can be repaired by simply removing and replacing it with a new one, making installation and maintenance extremely convenient. Since complex electronic iron removal equipment is not required, production costs are reduced. The production cost per tonne of quartz sand is reduced from 50 RMB to 22 RMB, saving 56% of production cost per tonne.

Detailed Description of the Embodiments

The present invention is further described in detail below with reference to specific embodiments.

例 1：

The mined raw quartz sand ore has a silicon content lower than 92%, an iron content between 0.2% and 0.25%, contains a large amount of impurities, and has a wide particle size distribution.

After preliminary beneficiation, the raw quartz sand ore undergoes the following process steps:

1. Under the action of water flow, the preliminarily beneficiated ore flows through a channel into vertically arranged screen meshes for screening. The screen meshes are arranged in two layers, with the upper screen being 20 mesh and the lower screen being 130 mesh. Coarse sand larger than 20 mesh and fine sand smaller than 130 mesh are both removed. The sand with particle sizes between 20 mesh and 130 mesh is collected and enters the channel.
2. The screened sand flows through a channel into a desliming machine for desliming to remove the mixed mud and sand.
3. The deslimed sand flows through a channel into a scrubber for scrubbing to further remove impurities.
4. The scrubbed sand is then classified to produce a finished quartz sand product with a silicon content higher than 96%, an iron content lower than 0.15%, extremely low impurity content, and a particle size between 20 mesh and 130 mesh.

例 2：

The mined raw quartz sand ore has a silicon content lower than 92%, an iron content between 0.2% and 0.25%, contains a large amount of impurities, and has a wide particle size distribution.

After preliminary beneficiation, the raw quartz sand ore undergoes the following process steps:

1. Under the action of water flow, the preliminarily beneficiated ore flows through a channel into vertically arranged screen meshes for screening. The screen meshes are arranged in two layers, with the upper screen being 20 mesh and the lower screen being 100 mesh. Coarse sand larger than 20 mesh and fine sand smaller than 100 mesh are both removed. The sand with particle sizes between 20 mesh and 100 mesh is collected and enters the channel.
2. The screened sand flows through a channel into a desliming machine for desliming to remove the mixed mud and sand.
3. The deslimed sand flows through a channel into a scrubber for scrubbing to further remove impurities.
4. The scrubbed sand is then classified to produce a finished quartz sand product with a silicon content higher than 96%, an iron content lower than 0.15%, extremely low impurity content, and a particle size between 20 mesh and 100 mesh.

例 3：

The mined raw quartz sand ore has a silicon content lower than 92%, an iron content between 0.2% and 0.25%, contains a large amount of impurities, and has a wide particle size distribution.

After preliminary beneficiation, the raw quartz sand ore undergoes the following process steps:

1. Under the action of water flow, the preliminarily beneficiated ore flows through a channel into vertically arranged screen meshes for screening. The screen meshes are arranged in two layers, with the upper screen being 24 mesh and the lower screen being 100 mesh. Coarse sand larger than 24 mesh and fine sand smaller than 100 mesh are both removed. The sand with particle sizes between 24 mesh and 100 mesh is collected and enters the channel.
2. The screened sand flows through a channel into a desliming machine for desliming to remove the mixed mud and sand.
3. The deslimed sand flows through a channel into a scrubber for scrubbing to further remove impurities.
4. The scrubbed sand is then classified to produce a finished quartz sand product with a silicon content higher than 96%, an iron content lower than 0.15%, extremely low impurity content, and a particle size between 24 mesh and 100 mesh.

Example 4:

The mined raw quartz sand ore has a silicon content lower than 92%, an iron content between 0.2% and 0.25%, contains a large amount of impurities, and has a wide particle size distribution.

After preliminary beneficiation, the raw quartz sand ore undergoes the following process steps:

1. Under the action of water flow, the preliminarily beneficiated ore flows through a channel into vertically arranged screen meshes for screening. The screen meshes are arranged in two layers, with the upper screen being 24 mesh and the lower screen being 130 mesh. Coarse sand larger than 24 mesh and fine sand smaller than 130 mesh are both removed. The sand with particle sizes between 24 mesh and 130 mesh is collected and enters the channel.
2. The screened sand flows through a channel into a desliming machine for desliming to remove the mixed mud and sand.
3. The deslimed sand flows through a channel into a scrubber for scrubbing to further remove impurities.
4. The scrubbed sand is then classified to produce a finished quartz sand product with a silicon content higher than 96%, an iron content lower than 0.15%, extremely low impurity content, and a particle size between 24 mesh and 130 mesh.

Example 5:

Under the action of water flow, the preliminarily beneficiated raw quartz sand ore flows through a channel into screen meshes for screening. The screen meshes are arranged in three layers, with the upper screen being 20 mesh, the middle screen being 80 mesh, and the lower screen being 100 mesh. Coarse sand larger than 20 mesh and fine sand smaller than 100 mesh are removed. The sand with particle sizes between 20 mesh and 100 mesh is collected and enters the channel. A channel is provided between the upper and middle screen meshes for the sand with particle sizes between 20 mesh and 80 mesh to flow into the desliming and subsequent processes. A second channel is provided between the middle and lower screen meshes for the sand with particle sizes between 80 mesh and 100 mesh to flow into the desliming and subsequent processes. Other process steps are the same as in Example 1.