钒渣空白焙烧清洁提钒工艺探讨

Technology Research on Clean Vanadium-extracting from Vanadium Slag by Blank Roasting

针对现有钒渣提钒工艺成本高、固废量大的问题,提出钒渣空白焙烧—碳酸化浸出制备氧化钒新工艺,重点研究了空白焙烧、碳酸化浸出工艺条件。结果表明,钒渣在860~900℃空白焙烧后,钒主要以Mn2V2O7、Mg2V2O7形式存在;熟料在碳酸氢钠浓度158 g/L、浸出温度95℃、浸出时间120 min等条件下浸出,钒转浸率为90.49%~92.12%;浸出液经偏铝酸钠除硅、碳酸氢铵沉钒制备的五氧化二钒产品符合质量标准YB/T 5304—2017的要求。设计的工艺路线可实现钠、氨介质的循环利用,具有工艺成本低、固废少等特点。

Aiming at the problems of high process cost and large amount of solid waste in existing vanadium extraction process from vanadium slag,a new process for preparing vanadium oxide from vanadium slag by blank roasting and carbonation leaching was proposed.The research mainly focused on the conditions of blank roasting and carbonation leaching.The results show that vanadium mainly exists in the form of Mn2V2O7 and Mg2V2O7 after blank roasting of vanadium slag at 860~900℃,and 90.49%~92.12%of vanadium leaching rate can be achieved under conditions as follows:concentration of NaHCO3 158 g/L、leaching temperature 95℃、leaching time 120 min;and V2O5 which satisfies the YB/T 5304—2017 standard can be obtained by adding sodium aluminate in the leachate for silicon removal and precipitating vanadium with NH4HCO3.The designed process route can realize the recycling of sodium and ammonia media,and has the characteristics of low process cost and less solid waste.