机械力化学效应提高铁尾矿活性研究

为提高铁尾矿的活性,实现尾矿的高附加值大宗利用,以司家营铁尾矿为原料,采用单独机械活化与添加助磨剂机械力化学活化的方法提高铁尾矿活化程度,并通过水泥胶砂试验、火山灰活性测试、XRD、FT-IR以及SEM检测手段探究了助磨剂对提高尾矿活性的影响.结果表明:单独对尾矿粉磨后,活性有所提高,粉磨3h活性指数可达到86.4％;对照机械力粉磨3 h,采用添加助磨剂机械力化学粉磨的尾矿活性指数均高于单独机械力粉磨时尾矿的活性指数,尤其采用掺有0.7％脱硫石膏的尾矿粉湿磨3h的方法活性指数最大,达到91.72％,且具有火山灰活性,可考虑作为活性材料制备混凝土.通过XRD、FT-IR和SEM表征发现,机械力化学活化的方式使晶体无定型程度进一步加深,可能是在断裂的石英表面,吸附了一层或多层金属离子,减弱了团聚效应,导致更多的Si-O键发生断裂,从而提高粉磨效率,致使颗粒的粒度继续下降,活性相较于单独粉磨有了进一步的提高.

Experimental study on improving the activity of iron tailings by mechanochemical effect

In order to improve the activity of iron tailings and realize the high value-added large-scale utilization of tailings, the method of adding separate mechanical activation and adding grinding aid mechanical chemical activation was used to improve the activation degree of iron tailings, and the effects of grinding aid on the activity of tailings were analyzed by cement mortar experiment, pozzolanic activity test, XRD, IR and SEM. The analysis results showed that: After grinding the tailings separately, the activity is improved, especially after grinding for 3 hours, the activity index reaches 86.4%; the activity index of the tailings by adding grinding aids is generally higher than that by grinding alone, while the activity index of the tailings by wet grinding with 0.7% desulfurized gypsum for 3 hours is the largest, reaching 91.71%, and has pozzolanic activity, which can be considered as active The concrete is made of sex materials. Further analysis shows that the action mode of grinding aids may be that one or more layers of metal ions are adsorbed on the fractured quartz surface, which weakens the agglomeration effect, thus improving the grinding efficiency, further reducing the particle size, breaking more Si-O bonds, and further improving the activity compared with the single grinding.