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Vanadium is a major element of the production of alloy steels and superalloys, is an important strategic material, has a wide range of applications, and good market prospects. Of vanadium resources in the country, and a wide variety of vanadium-containing ore, vanadium extraction process with each passing day. With the international and domestic markets vanadium pentoxide prices skyrocketing everywhere on Martinique vanadium project. But in the process of vanadium extraction, not only low vanadium recoveries, but also caused serious environmental pollution and waste of resources. With the continued exploitation of mining resources, emissions and store the amount of tailings growing surge due to mineral resources are non-renewable resources, demand for resources, mineral resources become increasingly scarce today, the implementation of the comprehensive utilization of tailings , for the recovery of valuable elements imperative. Tailings containing vanadium the converter steelmaking of vanadium slag is extracted several times tailings, is an intractable of vanadium-bearing minerals. The tailings containing vanadium remains high, both in terms of resource utilization and environmental protection, recycling vanadium significant. The papers on the basis of a comprehensive overview of domestic and foreign tailings for its mineral characteristics, proposed new process from vanadium tailings leaching vanadium and related theoretical studies. In this experiment, the Panzhihua Iron and vanadium-containing tailings as raw materials, reference the Pangang converter Vanadium Extraction, combined with the research vanadium extraction of vanadium slag, steel slag and stone coal from tailings vanadium valence state and its solubility proceed, combined Thermodynamics of the sulfuric acid leaching, pressure leaching and R1 nature, analysis of the feasibility of the experimental program. Panzhihua Iron and vanadium-containing tailings were used direct pressure acid leaching and atmospheric combination of leaching process, the high recovery of atmospheric pollution-free are not roasting process leaching vanadium. First through the mineral chemical analysis, X-ray phase analysis and particle size analysis, detection tailings vanadium content and form; pressurized and atmospheric exploration experiments followed by the experimental conditions, all aspects of the leaching rate of vanadium compared to verify the correctness of leaching theory; pressure and atmospheric leaching conditions of experimental and atmospheric leaching orthogonal and two paragraphs contrast verification experiment by several influential factors affecting the leaching rate of vanadium; then leaching slag and liquid analysis; Finally, the optimum leaching conditions and process containing vanadium tailings leaching vanadium. The experimental results show that: in order to vanadium in vanadium-containing tailings leaching must destroy the mineral structure, the vanadium released oxidant cheap vanadium oxidation to the high price of a soluble vanadium. Comparative experiments show: pure sulfuric acid leaching leaching rate is relatively low, and the pressure field and atmospheric combination of leaching, can damage the mineral structure of the tailings, the leaching rate increased substantially. Acid leaching vanadium process influencing factors such as acid concentration, the amount of oxidant, acid leaching temperature, leaching time, oxidants were investigated and optimized to obtain the optimum operating point parameters. Pressure leaching and atmospheric composition containing vanadium tailings leaching vanadium leaching rate of up to 68% and 85%, respectively. Which reagent dosage and liquid to solid ratio of vanadium leaching greater impact, particle size, reaction time and temperature and oxidant species has less impact. By orthogonal experiments and two-stage leaching explore the vanadium-containing tailings not be suitable for the two paragraphs leaching. Finally containing vanadium tailings leaching process conditions and process flow diagram. The optimum conditions for: grinding to a particle size of less than 0.25mm (60 mesh) accounted for 95% of the vanadium-containing tailings, ore slurry solid ratio 5:1, the initial H2SO4 150g · L-1, Rl concentration of 30g · L -1 oxidant KM04 3.33wt% (5g), leaching temperature of 85 ° C, 4h, stirring speed 500r/min. Compared with traditional sodium roasting, leaching vanadium pure wet, both to solve the production of exhaust pollution problems, but also comprehensive utilization of resources, with the advantages of low-cost, non-polluting, simple operation, less investment in equipment, there is a good economic, environmental and social benefits.
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