A Novel Flowsheet for the Separation and Recycling of Vermiculite Concentrate

Vermiculite is a kind of greatly valuable non-metallic mineral in nature. It is of great significance to separate the pure vermiculite concentrate and mixed tailing from the mining vermiculite crude ore with a high-efficiency and pollution-free flowsheet. The distributed condition and application situation of vermiculite in the world were sum up. The particle size distribution and chemical composition of vermiculite crude ore were analyzed. A self-developed hammer crusher and active pulsing air classifier were used to achieve the complete crushing and effective separation of the vermiculite in this novel flowsheet. Vermiculite crude ore was crushed to the size of 0.5~1.0mm firstly and a separation experiment was conducted with the active pulsing air classifier. The experimental results indicate that the complete peeling off and full dissociation of vermiculite could be achieved through two-level crushing. The highest separation efficiency of 91.16% and concentrate grade of 91.51% could be obtained with the feeding capacity of 13.98Kg/h, the pulsing air velocity of 2.36m/s and the pulsing frequency of 1.165Hz. The expansion character of vermiculite concentrate was utilized to realize the secondary purification of the productions after separation. This novel flowsheet has great potential to be applied in the field of vermiculite purification and recycling.