To improve the strength of red mud cemented back-filling materials,both separate milling and step milling techniques were used and their effects on grain size distribution and hydration processes were also investigated.The results showed that the compressive strengths of the samples of 1-day,3-days and 28-days curing prepared by step milling were 21%,16.6%and 3.7%higher than those of the samples prepared by separate milling.Larger surface area of the mixed powder could also be obtained by step milling technique than separate milling technique.The medium particle size of the mixed powder obtained by step milling technique and separate milling technique are 3.30 and 4.38μm,respectively.The SEM analysis suggested that the samples by step milling technique had much quicker increasing of hydroxide products than that of the samples by separate milling technique.%为提高胶结充填材料的强度性能,试验研究了分别粉磨和梯级粉磨工艺对赤泥全尾砂胶结充填材料强度性能、粉体粒径以及水化过程的影响.结果表明：梯级粉磨工艺下试块的1、3、28 d最大抗压强比分别粉磨工艺下试块1、3、28 d最大抗压强度分别高出21%、16.6%、3.7%;梯级粉磨工艺使物料粉体的比表面积均高于分别粉磨工艺的粉体比表面积;梯级粉磨工艺下粉体中粒径为3.30μm,明显小于分别粉磨工艺粉体4.38μm的中粒径;SEM分析看出梯级粉磨工艺下试块水化产物生长较快.粉磨工艺对赤泥全尾砂胶结充填材料强度性能、水化过程及粉体粒径均有影响.梯级粉磨工艺比分别粉磨工艺更有利于提高充填料性能.
展开▼
