某低品位白钨矿磨矿浸出试验研究

Experimental Study on Grinding Leaching of Low Grade Scheelite

低品位白钨矿的传统处理方法为高温焙烧-浸出,随着环保问题的日益严重,高温焙烧不仅需消耗大量煤炭,还会产生温室气体污染环境,既降低了经济效益又增加了环保压力。本文以磨矿代替焙烧研究了磨矿浸出工艺从低品位白钨矿中提取钨,考察了磨矿时间、碳酸钠浓度、磨矿频率、磨矿液固比等因素对钨浸出率的影响,旨在降低高温焙烧影响的同时,探究出符合企业要求的浸出工艺。结果表明:最优磨矿条件为磨矿时间8 min、碳酸钠浓度165 g/L、磨矿频率45 Hz、磨矿液固比1∶1,磨矿后加入适量辅助试剂氧化镁、氢氧化铝和氢氧化钠,在浸出温度205℃、搅拌速度300 r/min、浸出液固比5:1、浸出时间120 min条件下再进行加压浸出,钨浸出率可达98.66%。采用磨矿-浸出法处理低品位白钨矿环保高效,对同类矿石处理具有借鉴意义。

The traditional treatment method of low-grade scheelite is high-temperature roasting leaching.With the in-creasingly serious environmental problems,high-temperature roasting not only consumes a large amount of coal,but also produces greenhouse gases to pollute the environment,reducing economic benefits and increasing environmental pres-sure.In this paper,the grinding leaching process was studied to extract tungsten from low-grade scheelite by grinding instead of roasting.The effects of grinding time,sodium carbonate concentration,grinding frequency,grinding liq-uid-solid ratio and other factors on tungsten leaching rate were investigated.The purpose was to reduce the impact of high-temperature roasting and explore the leaching process that meets the requirements of enterprises.The results showed that the optimum grinding conditions were grinding time of 8 min,sodium carbonate concentration of 165 g/L,grinding frequency of 45 Hz,grinding liquid solid ratio of 1∶1.After grinding,appropriate auxiliary reagents such as magnesium oxide,aluminum hydroxide and sodium hydroxide were added.Under the conditions of leaching temperature of 205℃,stirring speed of 300 r/min,leaching liquid solid ratio of 5∶1,and leaching time of 120 min,the tungsten leaching rate was 98.66%.The grinding leaching method is environmentally friendly and efficient in treating low-grade scheelite,which can be used for reference in the treatment of similar ores.