METHOD FOR THE DRY BENEFICIATION OF WOLLASTONITE ORES

摘要

The invention relates to the beneficiation of mineral deposits and can be used for beneficiating wollastonite ores. The method for the dry beneficiation of a wollastonite ore involves the primary and secondary crushing of the ore, the material drying between said crushing stages, the X-ray fluorescent separation of the crushed material after the secondary crushing stage, the classification of the material according to grain-size categories immediately after the X-ray fluorescent separation by sequentially carrying out impact grinding, magnetic separation on a belt conveyor, and air sizing. Then, the method involves the magnetic separation on a roll-type separator for removing impurities from the different size wollastonite concentrate and the extraction of material flour particles at the primary and secondary crushing stages and during the impact grinding of the ore. All the extracted flour particles are delivered to one of the rolls of the roll-type separator, the wollastonite concentrate of one or more grain-sizes is dried and, then, the dried concentrate is exposed to electrostatic separation for removing impurities therefrom. Subsequently, the air sizing of the product received after electrostatic separation is carried out in order to divide said product into fractions having different grain-size. One or more product fractions are additionally crushed and electrostatic charge is removed. The proposed invention makes it possible to improve the product quality and to reduce wollastonite waste.