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The paper based on the comprehensive utilization of resources containing magnesium, nickel, nickel serpentine, Fujian nickel-containing serpentine (including 0.22% nickel, containing 37.4% magnesium oxide) as the research object, in the the ore chemical multi-element analysis and physical phase analysis basis, developed using strong acid leaching process to deal with the technical solution of the nickel-containing serpentine, sulfuric acid, hydrochloric acid atmospheric leaching and pressure leaching process test of the system, establish a sulfuric acid pressure leaching serpentine mine new technology roadmap and process conditions to obtain a high-quality and high recovery of nickel sulfide, magnesia products, nickel-containing serpentine nickel, magnesium resources recovery. Papers by single factor test to explore the sulfuric acid, hydrochloric acid atmospheric leaching nickel-containing serpentine optimize the process conditions. In the atmospheric leaching sulfate optimization process conditions, serpentine nickel, magnesium leaching rate can only reach 50.7% and 61.1%, nickel, magnesium leaching rate is very low. Hydrochloric atmospheric leaching under the optimized conditions, nickel, magnesium leaching rate can be up to 93.6% and 82.2%, but the reaction is difficult to control, and hydrochloric acid at high temperature conditions to greater losses. Through single factor test hydrochloric acid pressure leaching process optimization: ore particle size less than 0.074mm content of 74.5%, acid mine than 1.25, the reaction time of 60 min, the reaction temperature of 110 ° C (pressure of 143.0 kPa ), stirring speed of 500 rpm, liquid to solid ratio of 4, the conditions under nickel, the magnesium leaching rates were 96.1% and 85.1%. By addition, iron sulfide, Nickel, hydroxide sink magnesium, magnesium hydroxide, calcining step from containing nickel, magnesium and the leaching solution was prepared qualified nickel sulfide and magnesium oxide product, wherein the product contains 6.28% nickel of the nickel sulfide, nickel ultimate recovery of 73.6%, 95% MgO content of magnesia products, magnesium ultimate recovery of 70.0%. Economic estimates show that, hydrochloric acid pressure leaching process costs are high, it is difficult to become an effective way of containing nickel, magnesium, nickel serpentine resource recovery. Through single factor test established by the sulfuric acid pressure leaching process optimization: ore particle size less than 0.074 mm content accounted for 74.5% of the acid mine than 0.6, the reaction time of 120 min, the leaching reaction temperature is maintained at 110-120 ° C for stirring speed of 500 rpm, liquid to solid ratio of 4.0, and the conditions under nickel, magnesium leaching rate was 95.6% and 90.2%, respectively. Leaching solution jarosite law in addition to iron, iron removal rate can reach 93.2%; sodium sulfide Nickel can get products containing Ni 7.8% nickel sulfide, nickel ultimate recovery rate can reach 81.7%; using sodium hydroxide Shen magnesium, magnesium precipitation rate was 96.5%, up to 75.5% of the ultimate recovery of magnesium; magnesium hydroxide is calcined at 800 ℃ for 60 min, the magnesia products containing MgO 97.1%, the main ingredient and impurities meet HG/T2573-94 standard in superior product requirements. The experimental results and economic estimates suggest that the sulfuric acid pressure leaching process handling nickel-containing serpentine, equipment corrosion is relatively small, low energy consumption, processing, wastewater recycling, product quality, etc., is a for nickel-containing serpentine ore, nickel, magnesium integrated resource recycling promising new technology.
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