石煤提钒钠化焙烧与钙化焙烧工艺研究

调研了石煤提钒钠化焙烧和钙化焙烧两种工艺的发展现状。高硅低钙含量的石煤宜采用钠化焙烧,高钙含量的石煤宜采用钙化焙烧,两种工艺各有所长。归纳了两种工艺下石煤提钒的最佳焙烧条件,得出最佳焙烧条件分别为:钠化焙烧温度区间800～850℃,焙烧时间2.0～2.5h,磨矿粒度106～180um,氯化钠用量为矿石的10%～20%。钙化焙烧比钠化焙烧要高100℃,温度区间900～950℃,焙烧时间2～3h,磨矿粒度106～180um,石灰用量为矿石的6%～8%。两种焙烧都需要充足的氧化氛围,但钠化焙烧时氧气不宜过多。各最佳焙烧条件之间存在一定耦合关系,在生产实际中,宜针对不同石煤进行特定实验。最后,总结了石煤提钒的主要焙烧设备,其中流化床炉具有较好的发展前景。

Review of Vanadium Extraction from Stone Coal by Roasting Technique with Sodium Chloride and Calcium Oxide

The development of technology on vanadium extraction from stone coal by adding sodium chloride and calcium oxide was reviewed. Stone coal with large amount of silica and low in calcium was suitable for roasting with sodium chloride. Stone coal with large amount of calcium was suitable for masting with calcium oxide. Both techniques had advantages. The optimum additive dosage, roast-ing temperature and roasting time were concluded. When adding sodium chloride, roasting temperature of 800 ～ 850 ℃, roasting time of 2.0 ～2.5 h, granularity of 106 ～180 nun, salt dosage of 10% ～20% were found to be the best conditions for roasting. Compared with roasting with sodium chloride, roasting temperature of 900 ～950 ℃, roasting time of 2 ～3 h, granularity of 106 ～ 180 mm, calci-um oxide dosage of 6% ～ 8% were the best conditions for roasting with calcium oxide. Both techniques needed sufficient oxidizing at-mosphere. When roasting with sodium chloride, it was by no means the more oxygen the better. There were coupling relationships a-mong different optimum conditions. In practical production, special experiments should be conducted for different kinds of stone coal. Different roasting furnaces were summarized that circulating fluidized bed (CFB) had more advantages than others.