新疆某难处理含钒石煤焙烧—酸浸提钒试验研究

新疆某难处理含钒石煤中钒以极细粒分布在绢云母中，现场采用传统焙烧系统进行空白焙烧提钒，存在氧气浓度低、温度控制难等问题，最终钒浸出率仅为20%左右。为此，在充分分析原矿性质的基础上，采用自行设计的气基焙烧系统进行石煤原矿的空白焙烧试验研究，条件试验确定适宜的焙烧温度为800 ℃、焙烧时间为20 min、气体流量为400 mL/min、氧浓度为20%；对此条件下获得的焙烧样进行酸浸提钒，固定硫酸浓度30%、液固比1.25∶1、浸出时间3 h、浸出温度90 ℃，最终钒浸出率可达46.51%。研究结果表明新装置具有焙烧温度低、焙烧时间短、对矿石的选择性小、焙烧气氛精准可调等优点，可有效降低生产成本、提高生产效率。

Experimental Study on Vanadium Extraction from a Refractory Vanadium-bearing Stone Coal in Xinjiang with Roasting and Acid Leaching Process

The vanadium in a refractory vanadium-bearing stone coal in Xinjiang is distributed in sericite with very fine particles. The traditional roasting system was used for blank roasting to extract vanadium， but there were some problems such as low oxygen concentration and difficult temperature control， and the final leaching rate of vanadium was only about 20%. Therefore， on the basis of fully analyzing the properties of raw ore， a self-designed gas-based roasting system was used to carry out blank roasting test of the stone coal ores. The optimum roasting temperature， roasting time，gas flow and oxygen concentration were determined to be 800 ℃， 20 min， 400 mL/min and 20% by condition test. The roasted samples were obtained under the appropriate condition. Finally， the leaching rate of vanadium can reach 46.51% by acid leaching with fixed concentration of sulfuric acid at 30%， liquid-solid ratio of 1.25∶1， leaching time of 3 h and leaching temperature of 90 ℃. The results showed that the new device has the advantages of low roasting temperature， short roasting time， low selectivity to ore， precise and adjustable roasting atmosphere， which can effectively reduce the production cost and improve the production efficiency.