Nickel is a kind of nonferrous metal, which can be combined with many metal elements to form alloy, stainless steel, nickel base alloy and other materials. When the nickel content exceeds 3%, it can be directly smelted for the production of various materials, but when it is less than 3%, it can only be smelted after being separated and purified by the beneficiation process and supporting beneficiation equipment.
According to the different compositions of nickel ores, the selected process methods are also different. The process flow can be divided into several stages: crushing screening grinding classification separation tailings treatment. In this paper, we will take you to understand the nickel ore dressing equipment of each process.
Three stage one closed circuit crushing and screening process can be adopted in nickel ore crushing and screening stage. The raw ore is fed into the primary crushing section from the feed bin, and then crushed into the secondary crushing section. When crushed to a certain particle size, it is sent to the screening machine by the belt conveyor. The screened material returns to the secondary crusher, while the screened material enters the grinding section. Nickel ore equipment used in this stage includes crusher, screening machine, belt conveyor and ore feeding bin.
Crusher: jaw crusher and cone crusher are mainly used. Generally, the primary crushing is, and the secondary and tertiary crushing are cone crushers;
Screening machine: there are circular vibrating screen and linear vibrating screen.
Two stage closed circuit grinding operation can be adopted for grinding and screening. The qualified materials after crushing are sent to the first stage ball mill by the conveyor, and then they are graded. The overflow products are returned to the first stage for regrinding. The qualified materials of underflow are sent to the second stage ball mill for fine particle grading after grinding. After grading, the qualified products enter the sorting stage, and the overflow products are returned to the second stage for regrinding. Nickel ore dressing equipment used in the grinding and classification stage includes: overflow ball mill.
Lattice ball mill: generally used for primary grinding;
Overflow ball mill: generally used for secondary grinding for fine grinding;
Screw classifier: in the primary grinding operation, cooperate with the lattice ball mill for classification;
Hydrocyclone: in the second stage grinding operation, cooperate with the overflow ball mill for classification.
The nickel ore dressing stage mainly includes flotation method and gravity concentration method. According to different ore properties, different processes are selected.
(1)Nickel ore flotation equipment
Flotation is mostly suitable for treating nickel sulfide ore containing silicate gangue or nickel mineral with uneven particle size. According to different mineral properties, the commonly used flotation methods include preferential flotation method and mixed flotation method.
Priority flotation: copper flotation and nickel suppression process is adopted. The milled products are sent to the agitation tank, sulfide inhibitor and copper collector are added, and after full mixing, they are sucked into the flotation machine for flotation operation. The flotation foam products are copper concentrate, and the tailings are nickel products. The tailings need to enter the next flotation stage, and nickel concentrate can be obtained by adding sulfide ore collector for flotation.
Mixed flotation: after grinding, the pulp enters the mixing tank, and after fully mixing with the flotation reagent, the mixed concentrate of copper and nickel will be floated out first, and the mixed concentrate will be sent to the ball mill for stage grinding, so that the two minerals can be separated in a single step and then enter the next stage of flotation. Before flotation, the pulp will be sent into the mixing tank, and the agent for inhibiting sulfide and collecting copper will be added. After fully mixing, the copper concentrate will be floated out, while the tailings in the flotation tank are nickel concentrates.
Nickel ore dressing equipment used in the flotation stage includes: flotation machine, agitation tank, beneficiation reagent and lifting pump.
Flotation machine: KYF flotation machine, SF flotation machine, among which JJF flotation machine and SF flotation machine can form a combined unit, KYF flotation machine and XCF flotation machine can form a combined unit;
Mixing tank: mainly including reagent mixing tank, high efficiency mixing tank and conventional mixing tank;
Beneficiation reagents: mainly nickel sulfide ore collector and silicate ore inhibitor.
(2)Nickel ore gravity concentration equipment
The heavy medium beneficiation method is generally adopted for nickel ore gravity concentration, which is suitable for handling iron nickel platinum copper nickel minerals. By using the density difference between gangue and nickel sulfide ore, the slurry is fed into the heavy medium cyclone with a pressure of 0.05~0.20Mpa for separation. The low flow part is nickel sulfide ore, while the overflow is silicate gangue ore. Nickel ore equipment used in heavy medium beneficiation method includes heavy medium cyclone.
The above are the methods and types of beneficiation equipment used. In the actual concentrator, the specific equipment to be selected depends on the beneficiation process flow. Therefore, it is necessary to design a reasonable nickel ore beneficiation process flow through beneficiation test, and then customize reasonable beneficiation equipment to effectively improve nickel ore recovery and obtain an ideal return on investment.
