复合激发剂对铜炉渣活性影响及充填材料制备

为了实现铜炉渣的废物利用,以碱激发方式为主研究铜炉渣制备矿用胶凝材料的可能性.选取生石灰、NaOH和早强剂组成的混合物作为复合激发剂,开展铜炉渣活性激发和充填材料制备试验,并采用X射线衍射和扫描电子显微镜对铜炉渣水化产物进行分析.试验结果表明,各激发剂对铜炉渣活性的影响顺序依次为生石灰 > 早强剂 > NaOH,在复合激发剂的作用下炉渣净浆试样的7和28 d强度分别可以达到1.5和3.0 MPa以上.铜炉渣尾砂充填料28 d强度为1.0 MPa,流动性良好,满足充填材料要求.铜炉渣早期水化产物主要有片状的Ca(OH)₂和C-S-H凝胶,随着养护时间的增加,C-S-H凝胶Ca/Si比不断减小,水化产物结构更加致密.养护时间至28 d时,铜炉渣中活性成分基本反应完全.

Effect of compound activator on copper slag activity and preparation of filling materials

The preparation of cementitious materials for filling primarily via the alkali-activated method was discussed to recycle copper slags. A mixture of lime, NaOH, and early-strength agent was selected as a composite activator to carry out copper slag activation and filling material-preparation experiments, and the hydration products were analyzed by X-ray diffraction and scanning electron microscopy. The test results show that the effect of different activators on sample strength follows the order lime > early-strength agent > NaOH. The strengths of slag paste samples at 7 and 28 d post-curing reach 1.5 and 3.0 MPa, respectively. The strength of filling materials mixed by copper slag and tailings is 1.0 MPa as the curing ages are 28 d, and the slurry has well fluidity. These values meet the requirements of a suitable filling material. The early hydration products of copper slag mainly include Ca(OH)₂ and C-S-H gel. As the curing time increases, the Ca/Si ratio of the C-S-H gel decreases and the structure of the hydration products becomes more compact. After curing for 28 d, the active components in the copper slag are nearly completely reacted.