激发剂强化钢渣磁选尾渣胶凝活性的研究

Research on cementitious activity of steel slag tailings after magnetic separation by activator

钢渣是冶金工业排放的大宗量废渣,其胶凝活性的激发主要通过机械和化学两种方式。为了确定钢渣化学激发适宜的激发剂组分,以提高钢渣资源化的利用效率,本文以钢渣磁选尾渣作为研究对象,分别用硅酸盐、碳酸盐、硫酸盐等激发剂掺混钢尾渣进行机械粉磨,激发其胶凝活性,并按照相关标准,测试钢尾渣粉的粒径分布、比表面积,以及钢尾渣水泥胶砂砌块7 d和28 d的活性指数。结果表明:化学激发剂用于掺钢尾渣粉磨,掺磨w(Na_(2)SiO_(3)·9H_(2)O)为0.1%的钢尾渣粉比表面积最大为495 m^(2)/kg;钢尾渣粉的比表面积与7 d活性指数趋势相同,平均粒径与28 d活性指数趋势相反;CaSO_(4)·2H_(2)O组分适宜对钢尾渣进行化学激发,掺w(CaSO_(4)·2H_(2)O)为1%球磨100 min的钢渣粉比表面积为404 m^(2)/kg,平均粒径为54.85μm,7 d和28 d活性指数分别为52.68%和94.41%。

Steel slag is a bulk waste residue discharged by metallurgical industry.The activation of its cementitious activity is mainly by means of machinery and chemistry.In order to determine the appropriate activator components for chemical activation of steel slag to improve the resource utilization efficiency of steel slag,the tailings of the steel slag after magnetic separation are taken as the research object.Such activators as silicate,carbonate and sulfate are used to blend steel slag tailings respectively for mechanical grinding and for stimulating its cementitious activity.According to relevant standard,the particle size distribution and specific surface area of steel slag powder are measured,and the activity index on cement mortar block of steel tailings of 7 d and 28 d is measured.The results show that,when the chemical activator is used for blending steel slag tailings powder grinding,the specific surface area of steel slag tailings powder is the largest of 495 m^(2)/kg after blending 0.1%w(Na2SiO_(3)·9 H_(2)O).The specific surface area has the same trend with the activity index at 7 d,while the average particle size has the opposite trend with the activity index at 28 d.The components of CaSO_(4)·2 H_(2)O is suitable for chemical excitation of steel slag tailings.Under the condition of blending 1%w(CaSO_(4)·2 H_(2)O)to mechanical grinding of mixed steel slag tailings for 100 minutes,the specific surface area of steel slag powder is 404 m^(2)/kg,the average particle size is 54.85μm,and the activity index of 7 d and 28 d are 52.68%and 94.41%respectively.