A highly synergetic method for clean utilization of high-carbon vanadium-bearing stone coal

Aiming at alleviating the difficulties of extracting vanadium from high-carbon stone coal and solving the relevant pollution problem, a new synergetic and cleaner method combining concentration of vanadium with clean utilization of carbon was proposed and corroborated. Firstly, Fe2O3, acting as the source for the catalytic of carbon gasification and the capturer of vanadium, was added to the raw ore. Then, the carbon within the raw ore was gasified by water vapor at 800-900 degrees C under the catalysis of reducing product of Fe2O3 (Fe3O4) to generate synthesis gas (CO + H-2), and subsequently the vanadium dispersive occurred in the ore was captured by Fe3O4 at 1100-1200 degrees C under Ar atmosphere to form FexV(3-x)O(4). Finally, the FexV3-xO4 phase was separated magnetically, and a high-grade vanadium concentrate was obtained. The experimental results show that the Fe3O4 effectively promoted the gasification rate and ratio of carbon. When 10 mass% Fe2O3 relative to raw ore was added and roasted at 850 degrees C for 2 h, the gasification ratio of carbon increased by 26%. The gasification ratio of carbon could reach up to 90.2%. Besides, the Fe3O4 could react with the V3+ components to form magnetic V-rich phase, FexV3-xO4, and the vanadium concentrate was obtained by magnetic separation. Under the optimal conditions, the vanadium concentrate with a metallic vanadium content of 6.35 mass% was obtained by magnetic separation, which was 23.5 times higher than the raw ore. The recovery ratio of vanadium reached 85.6%.

Automated summary

A new synergetic and cleaner method was proposed and verified to alleviate the difficulties of extracting vanadium from high-carbon stone coal and solve the associated pollution problems. The experimental results showed that the method effectively increased the gasification ratio and rate of carbon, and a high-grade vanadium concentrate was obtained through magnetic separation.