Mineral Processing
Chol Ung Ryom; Kwang Hyok Pak; Il Chol Sin; Kwang Chol So
Abstract
Shaking table and flotation are often used in scheelite (CaWO4) beneficiation, and usually they are applied in sequence. In this paper, analysis of mineral movement have been investigated in shaking table in which pulp was conditioned with xanthate as a collector and fed, heavy scheelite was concentrated, ...
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Shaking table and flotation are often used in scheelite (CaWO4) beneficiation, and usually they are applied in sequence. In this paper, analysis of mineral movement have been investigated in shaking table in which pulp was conditioned with xanthate as a collector and fed, heavy scheelite was concentrated, while heavy pyrite removed directly on the deck by the action of collector. Artificially mixed mineral with 1% scheelite and 2% pyrite was used in CFD simulations and experiments. Through CFD simulations, it was found that pyrite particles, which were hydrophobic by collector, were attached to the water-air interface and subjected to upward buoyancy, which increased the density difference between scheelite and pyrite particles and enabled the separation of both minerals in the shaking table. The experiment results showed that the concentrate grade in conventional table concentration was 23.5% WO3, the separation efficiency was 77.89%, while the concentrate grade of scheelite in the table concentration of xanthate presence was 65.0% WO3 and the separation efficiency was 80.88%. The combination of flotation in table with collector addition not only eliminated the flotation to remove pyrite after table but also resulted in a lower rate of scheelite loss.
M. Moghise; M. Pourrahim; B. Rezai; M. Gharabaghi
Abstract
This study aims to investigate and optimize the effects of the main parameters including the particle size, gravity and magnetic separation combination, high gradient magnetic separation, magnetic field intensity, shaking table slope, washing water flow, and electrostatic separation upon the rare earth ...
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This study aims to investigate and optimize the effects of the main parameters including the particle size, gravity and magnetic separation combination, high gradient magnetic separation, magnetic field intensity, shaking table slope, washing water flow, and electrostatic separation upon the rare earth element (REE) recoveries from iron mine waste. The electron microprobe showed that high amounts of REEs were distributed on the fluorapatite mineral, and hence, it was necessary to remove the high magnetic minerals by a low-intensity magnetic separation using a magnetic drum in an experimental procedure. A cyclic magnetic separator was used for the low-gradient magnetic separation. Moreover, a shaking table and an electrostatic separator were used to expand the recovery and grade of REEs. A combination of these methods was considered to optimize the REE recoveries based on the best combination including two steps of low magnetic separation, one step of medium intensity magnetic separation, a shaking table, and an electrostatic separator. Two low-intensity magnetic of 800 and 2000 gauss, one medium-intensity magnetic of 8000 gauss, a one-step shaking table with a water flow of 90 mL/s and a table slope of 3 degree, and one electrostatic separator of 25000 V with a blade angel of 20 degree had the best performance to separate REEs. The microscopic studies carried out showed that the monazite degree of freedom was between 75 and 105 micron. The results obtained showed that a particle size of ‒75 + 63 micron was a proper one to separate REEs. The total recovery and grade of the REE (Ce, La, Nd, Er, and Gd) concentrate obtained from the sample with a grade of 1499 ppm of REEs were 67.1 and 1.2%, respectively, at the optimum conditions. The results obtained showed that there was a direct relation between the phosphor grade and the REE recoveries, and that the REE recoveries increased by increasing the quantity of phosphor.
