| Nickel is a very important metal raw material, mainly used in the production of stainless steel. Jinchuan Nickel Mine is a copper and nickel symbiotic refractory polymetallic sulfide ore with high amount of magnesium, containing many associated minerals and high value in comprehensive utilization, which is China’s largest nickel deposit and also is one of the three oversize deposits of nickel sulfide in the world. In industry, the flotation is the common method to be used for separating copper-nickel sulfide ores. The main goal of copper-nickel sulfide ores flotation is to improve the nickel grade and recovery, and to reduce the MgO content.In this paper the rich nickel ores from the No.2mining area in Jinchuan were studied by some detection means, such as main composition of the raw ore, the tset of chemical phases, XRD, SEM-EDS and so on. The results show that:the nickel grade is1.36%, copper grade is0.86%and MgO grade is28.19%in the raw ore, nickel and copper mainly exist in the form of sulphide, and the distribution rate of nickel sulphide and copper sulphide are95.66%and91.86%respectively, the minerals are mainly pentlandite and Chalcopyrite. The main ganue minerals containing magnesium are serpentine, talc, chlorite and so on.On the basis of checking and reading a large number of domestic and internatonal related literature, and fully understanding of the properties of the raw ore, in this paper, complexing agent was used to clean and remove active irons, such as nickel and copper irons, from the surface of the gangue with MgO, which can eliminate the flotation activity of sulphide ore collector of xanthates. At the same time, the appropriate inhibitors were selected to enhance its surface hydrophilic, so as to remove the flotation activity of the gangue with MgO, which is an effective way of inhibiting the gang minerals with MgO in the flotation process of copper-nickel sulphide.For the characteristics of the Jinchuan nickel raw ores, a series of single factor experiment researches were conducted in this paper, mainly consider the effect that grinding fineness, pH value of pulp, complexing agents, inhibitors, foaming agent, collector agent and other factors take on the content of nickel, copper and MgO. and the recovery of nickel, so as to determine the best conditions of the rougher flotation. On this basis, closed-circuit test with once rough, twice concentration, three times scavenging was carried out, good flotation index was acquired and a concentrate was obtained, in which the rate of Ni, Cu, and MgO content was9.68%,5.04%, and6.33%, respectively, and the rate of Ni and Cu recovery is84.32%and69.13%, respectively, this index is better than result from the closed circuit by Jinchuan existing regime of reagent.At the same time, using various measuring and testing techniques such as X-ray diffraction analysis, scanning electron microscopy-spectroscopy (SEM-EDS) and infrared spectroscopy, the effect mechanisms of reagent in copper-nickel sulphide ore flotation had been investigated.The result of X-ray diffraction analysis showed that the main types of minerals contained in the concentrate product are pentlandite and chalcopyrite, and the major mineral species in the tailings product is serpentine, chlorite and so on.The test results of Scanning electron microscopy-spectroscopy (SEM-EDS) illustrated that:the main types of minerals contained in the concentrate product are pentlandite and chalcopyrite, the main minerals in tailings are gangue containing MgO, which are the same as the results of X-ray diffraction analysis.The results of FT-IR showed that new absorption peak of reagent was found in serpentine infrared spectroscopy after Cu2+activating, which indicated that butylxanthate absorpted the surface of serpentine and citric acid have the function of cleaning the activation Cu2+of the surface of serpentine. And pentlandite has good flotation activity. |
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