铁尾矿机械力-化学活化及胶凝材料制备

Mechanical-Chemical Activation of Iron Tailings and Preparation of Cementitious Materials

为提升铁尾矿火山灰活性,实现大宗化综合利用,本试验采用机械力-化学协同活化工艺激发铁尾矿活性,考察活化工艺对活性的影响,然后用活化铁尾矿制备胶凝材料,并研究铁尾矿净浆水化反应产物。结果表明,加入1.0%Na_(2)SiO_(3)再球磨60 min的铁尾矿活化效果最好,火山灰活性指数(PAI)为0.67;以活化铁尾矿代替基准水泥制备胶凝材料,当铁尾矿掺量为30%时,试块28 d抗压强度和抗折强度分别为30.48 MPa和4.93 MPa;活化铁尾矿净浆试块的水化产物为水化硅酸钙(C-S-H)凝胶和钙矾石、羟钙石,以及未反应的石英、菱铁矿等。

In order to improve the pozzolanic activity of iron tailings so as to achieve bulk comprehensive utilization,using mechanical-chemical co-activation process to stimulate the activity of iron tailings to study the influence of activation process on activity,then the activated iron tailings was used to prepare gelling materials,and the hydration reaction products of the net pulp of iron tailings was studied.The results showed that the iron tailings with 1.0%Na_(2)SiO_(3) added and then ball milling for 60 min had the best activation with the PAI of 0.67.When the iron tailings content was 30%,the 28 d compressive strength and fracture strength of the test block can reach 30.48 MPa and 4.93 MPa,respectively.The hydration products of the activated iron tailings net slurry test block were C-S-H gel and ettringite,hydroxyapatite and unreacted quartz,siderite and other mineral phases.