The influence of silica sand quality on glass production

June.28,2021

After the raw sand is mined, the finished sand is obtained after washing rod milling, classification, homogenization, and dehydration. The raw sand with particles below 10mm from the raw ore mining is conveyed into the rod mill through a belt. At the same time, add water according to a certain proportion and grind it into mortar and drain into the mortar pool. The slurry pump sends the mortar to the first-stage and second-stage rotary sieve to screen the first stage to 20 meshes, and the second stage to 22 meshes. The material larger than 0.5mm is returned to the rod mill and the material smaller than 0.5mm flows into the cone hydraulic classifier for classification. The graded sand has a particle size of 0.10~0.50mm and flows into the mortar tank. The slurry is pumped to a screw conveyor, further water is added for desliming, and finally into the silo, and sent to the per-capita homogenization silo by a transportation trolley for dehydration.

European current silica sand standard
The particle size range is 0.10~0.50mm. Gradation ratio: 1.25~1.00mm no more than 0.05%, 1.00~0.63mm no more than 5%, 0.63~0.1mm no less than 94%, less than 0.1mm no more than 1.5%;

The chemical composition of the particle size less than 100 mesh fluctuates severely, the content of sio2 is low, and the content of Fe2O3 and Al2O3 is high, which deviates far from the average value. The reason is that too fine sand often contains more clay impurities, which increases the iron content. Therefore, we must control the particle size ratio of silica sand. The following lists the particle size standards of European flat glass sand.

The composition of the sand is reasonable, which can increase the melting speed of the glass. Suqian sand is the most difficult raw material to melt in the batch. Whether its particle ratio is reasonable is the key to melting. Experiments show that the melting time of silica sand is proportional to its particle size.

The influence of iron content in silica sand on glass quality
In order to obtain high-quality silica sand, it is necessary to beneficiated to remove iron impurities, improve and stabilize the chemical composition, and ensure that the iron content of Suqian sand is less than 0.20%. Second, control its particle size in the range of 0.10~0.60mm.