通过对实验室模拟现场回转窑的6组不同温度点下焙烧渣样品进行钒尖晶石形貌变化、物相含量变化、钒元素的赋存规律及不同温度点下物相转变机理的研究。钒尖晶石形貌变化结果表明，整个焙烧过程中钒尖晶石形貌变化经历了致密光滑块状－氧化铁的镶边结构－钒尖晶石完全直接为隐晶质物质－小颗粒物质重新组合并且长大5个过程；矿物自动解理分析仪（MLA）物相含量分析数据显示焙烧过程中石灰石、铁橄榄石、钒尖晶石和白云石在逐渐减少，普通辉石相是逐渐增加，而氧化铁固溶体、部分氧化钒尖晶石、钒酸钙固溶体和铁板钛矿固溶体的变化趋势是先增加后减少；钒元素的赋存形式规律为绝大多数钒元素赋存于氧化物中，占到总量的85％左右，其次赋存于硅酸盐中，占到钒总含量的14％左右，还有极少部分分布于碳酸盐等矿物中；整个焙烧过程物相变化机理主要分为铁元素向外扩散－氧元素向内扩散－氧化物的化合过程－化合物雏形晶体的长大4个反应过程。%Six groups of roasting slag samples under different temperatures in rotary kiln were simulated in laboratory .T he morphology change of vanadium spinel ,the change of phase content ,the occurrence law of vanadium and the phase transformation mechanism under different temperatures were studied .The mor‐phology change results showed that the vanadium spinel underwent the following five processes :dense and smooth block‐shaped-rimmed texture of iron oxide-complete cryptocrystalline material of vanadium spi‐nel-recombination of small particles-growth .The content analysis results by mineral liberation analysis (MLA) indicated that limestone ,fayalite ,vanadium spinel and dolomite decreased gradually ,while the content of augite increased gradually .Meanwhile ,the iron oxide solid solution ,some vanadium spinel crystals ,calcium vanadate solid solution and pseudobrookite solid solution increased firstly and then de‐creased .T he vanadium w as mainly occured in oxides ,w hich accounted for about 80% .T he second occur‐rence state was silicate ,which accounted for about 14% .In addition ,very few vanadium elements were distributed in other carbonate minerals .The phase transformation mechanism in whole calcination process could be classified into four reaction processes ,i .e .,outward diffusion of Fe -inward diffusion of O -chemical combination of oxides-grow th of embryo crystals of compounds .
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