钒渣钙化焙烧-酸浸提钒试验研究

Experimental Research on Vanadium Extraction by Calcified Roasting and Acid Leaching

针对钒渣钙化焙烧一酸浸提钒工艺在工业试验过程中暴露出来的问题，以攀钢钒渣为原料，对影响提钒效果的关键工艺参数进行了研究。主要考察了混合料CaO／V2O5、熟料粒度、熟料金属铁、酸浸浆料终点pH值对钒转浸率的影响，焙烧气氛氧化性对最佳焙烧温度、浸出液P浓度对沉钒效果的影响。研究结果表明，在混合料CaO／V2050．54～0．70、熟料粒度为-0．096mm、熟料金属铁≤2％和浆料终点pH≤4．1时可获得较好的钒转浸率；当焙烧进气氧含量为15％（相应尾气氧含量-12．5％）时，最佳焙烧温度为850～870℃，相应的钒转浸率为88．29％～88．66％；酸性浸出液TV32g／L左右时，P浓度应控制在0．06g／L以下。

To solve problems arising during calcified roasting and acid leaching processes in vanadium extraction industrial test, the influence of key process parameters on extraction of vanadium was studied by taking vanadium slag from Pangang as raw materials. The research focused on the influence of Cao/ V2O5 ratio, roasted materials＇ particle sizes, metallic iron content in roasted materials and final pH value of leaching slurry on vanadium leaching rate and the influence of oxidizability of roasting atmosphere on the optimum roasting temperature, and the influence of P concentration of leaching liquid on precipitation of vanadium. The results show that a higher vanadium leaching rate can be obtained with CaO/ V2O5 ratio of 0.54 -0.70, the roasted materials＇ particle sizes of -0. 096 mm, metallic iron content in roasted materials equal to or less than 2% and the final pH value of leaching slurry not higher than 4. 1. With 15% of oxygen in inlet gas （the corresponding oxygen content in exhaust gas is about 12.5% ） , the optimum roasting temperature is 850 - 870 ℃ , and the corresponding vanadium leaching rate is 88.29% - 88.66%. When the acid leaching liquid contains 32 g/L of TV, P concentration should be controlled below 0.06 g/L.