Quartz refinement is a high difficult separation technology removing the bit or microimpurity and then get concentrated quartz or high purity quartz. Quartz refinement process mainly include washing, classification & desliming, scrubbing, magnetic separation, flotation, acid leaching, microbiological leaching, etc.
1. washing, classification & desliming
The SiO2 grade will be lower along with quartz particle size becoming fine, impurity ores grade will oppose. This phenomenon is obvious particularly in the quartz ore containing a large amount of clay. So it is necessary to washing and desliming before bebeficiation .
Scrubbing means removing the thin film on surface of quartz ore and mud impurity ore and further grating mineral aggregate by mechanical force and sand grinding & peeling force. Then classification and further purify quartz sand. At present, mainly use rod scrubbing and mechanical scrubbing.
It is great difficulty to separate the mica and quartz. Use the anion collector under acid condition or kation-anion collector under alkaline condition to flotine will get good effect. Generally, after scrubbing, desliming, magnetic and flotation, quartz purity will up to 99%.
4. Acid leaching
Thin acid is good for removing iron and aluminous, use thick acid and aqua regia to remove titanium and chrome. Generally, use mixed acid by above acids to remove impurity ore. According to requirements of final quartz product, control every factor of acid leaching and do the best to reduce acid concentration, temperature and dosage to control the production cost.
Use strong magnetic separator to remove the impurity iron is the key part. To reach a high quality of product quartz, the high intensity magnetic field is necessary to remove week magnetic impurity. In current years, strong magnetic separator is widely used to quartz dressing plant.