钙化焙烧粘土钒矿提钒过程的研究Ⅰ焙烧工艺的研究

Leaching Process of Vanadium from Argillaceous Vanadium Ore Using Calcified Roasting Ⅰ Study on Roasting Technology

采用钙化焙烧法对河南淅川粘土钒矿的焙烧工艺进行研究。通过对添加剂及添加量、焙烧温度和焙烧时间的研究,确定了最佳焙烧条件。结果表明,以Ca(OH)2为添加剂,其钙元素的添加量为钒矿的5%,900℃焙烧3 h的效果最佳。采用XRD和SEM等主要测试手段对钒矿和焙烧产物的晶相结构和显微结构进行表征,结果显示,钒矿中钒化合物为KAlV2Si3O10(OH)2,当分别采用CaO,CaCO3和Ca(OH)2作为添加剂时,其钒化合物分别转化为Ca2NaLiCrV3O12,Ca3LiMgV3O12和Ca2KMg2V3O12。由晶体数据和浸出实验可知,当钒的晶体结构由单斜晶系转化为立方晶系,且转化后晶体的晶胞参数越大时,钒的浸出率就越高。

Vanadium was leached from argillaceous vanadium ore by roasting with different amount calcium additives.Optimal roasting conditions were confirmed by experiments,and the result showed that,the best additive was Ca（OH）2,the Ca adding quantity was 5% of the vanadium ore,the roasting time of the mixture was 3 h and the roasting temperature was 900 ℃.The crystalline phases and microstructures of vanadium ore and roasted vanadium ore were characterized by TEM and XRD,and results showed that vanadium compound of vanadium ore was KAlV2Si3O10（OH）2.It was transformed to Ca2NaLiCrV3O12,Ca3LiMgV3O12 and Ca2KMg2V3O12 respectively when CaO,CaCO3 and Ca（OH）2 were added.Based on crystal data and the leaching experiments it was concluded that transformation of vanadium compounds from clinorhombic system into cubic system,was beneficial for vanadium,leaching rate and the compound unit cell parameter of latter system bigger was the vanadium leaching rate higher was.