Study On Smelting About Extracting Vanadium From Ferrophosphorous Containing Vanadium

Vanadium is widely used in the industy, Which is one of rare metals and has animportant strategic position. Dispersal, low-grade and difficult to extract are domesticvanadium resources’ status. The grade of vanadium contained in Ferrophosphorous is4~10%. So extracting vanadium from Ferrophosphorous Containing Vanadium issignificantly, it’s also one necessary way to ease the shortage of vanadium resources inour country.At present the problems that iron and nickel element can’t be recycled still exit andtoo much consumption of the reagent.etc. In this paper, the selective oxidation ofvanadium slag technique not only can solve these problems, but also can improve thegrade of vanadium in the slag. The selective oxidation was deeply analyzed in theory.The purpose of separation was achieved through a large number of experiments. theproblems of high power consumption and the refractory corrosion in traditional electricfurnace smelting，were solved in the experiment. Acheving the purpose of continuoussmelting in low energy consumption.The main results in this paper are as follows:1) Thermodynamic analysis of the selective oxidation of ferrophosphorous showed:When vanadium and chromium oxidation reaction occurs, they are largely oxidized intothe slag.Because their Gibbs free energy are much less than the oxidation reaction ofphosphorus, iron and nickel. Relatively low temperature is helpfull to improve theoxidation rate of vanadium. At low alkalinity alum spinel that formed V+3and FeOstably exist in the slag phase, and an appropriate increase alkalinity will raise the valence of vanadium in the slag. A large amounts of phosphorus in the molten iron hasgreat impact on the oxidation of vanadium, and nickel retain in the molten iron becauseit is hardly to be oxidized.2）The results of experiment show that oxidation rate of vanadium can reach about95%when blowing oxygen is140~160L in smelting ferrophospnorous. Not only ensurethe high oxidation rate of vanadium but also the amount of iron that enter the slag phaseis not be excessive. The activity of vanadium significantly increased and the activity ofFeO reduced when smelting in1350℃,so it is the optimal temperature to smelt. It had ahuge influence on the experimental results when added sodium carbonate. If sodiumcarbonate was added in10%,the oxidation rate of ferrum could reduce from40%to30%, meanwhile, the grade of vanadium that existends in the vanadium slag could beensured above10%and the oxidation rate of phosphorous slightly increased to55%.Atthe same time, the loss of gasification rate of vanadium reduced to content ranging from8%~11%and its oxidation rate was above95%. It is advantageous to reduce the amountof sodium modification treatment and, indirectly, the leaching amount of subsequentprocess by adding sodium carbonate.3）Using high bauxite refractory with a water-cooler copper pipe will solve theproblem of furnace lining. The lining of homemade smelting bag with water resultshows that:the appropriate water-cooled measures could ensure the lining keep longtime to smelting.4）Continuous smelting technology is a continuous process that ultimately achievelow power consumption. At the end of oxygen smelting, leave out vanadium slag, afterthat continue adding a certain amount of cold material. Making use of heat transferamong remaining molten iron in the smelting bag and then blowing oxygen to help thematerial to melt. It has solved a long-standing high energy defect in thepyrometallurgical smelting.