固硫灰基磷尾矿充填体的性能及浸出液水质  

Properties and Water Quality of Leaching Solution of Filling Material Composed with Desulphurization Ash and Phosphate Tailings

作　　者：刘冬梅[1] 刘玉娇 彭艳周[1] 卢希 Liu Dongmei;Liu Yujiao;Peng Yanzhou;Lu Xi(College of Civil Engineering and Architecture,China Three Gorges University,Yichang,Hubei 443002)

机构地区：[1]三峡大学土木与建筑学院,湖北宜昌443002

出　　处：《非金属矿》2020年第4期11-15,共5页Non-Metallic Mines

基　　金：国家自然科学基金(51809153)。

摘　　要：采用水玻璃、无水硫酸钠和生石灰共同激发固硫灰活性,制备固硫灰基磷尾矿胶结充填材料。探讨了生石灰掺量对充填体的泌水率、坍落度、抗压强度、变形性能的影响;通过X射线衍射(XRD)和扫描电子显微镜(SEM)研究了充填材料28 d龄期硬化体的微观结构组成及形貌;采用改进的模糊综合评价法对充填体浸出液的水质进行分析评价。结果表明,质量分数为66%,胶砂比1∶1时,当生石灰掺量从5%增至15%时,料浆坍落度减小至160 mm,泌水率几乎全为零,充填材料强度随生石灰用量的增加而明显增大,28 d抗压强度增至5.87 MPa,在干燥环境下的干缩变形明显减小,各项性能指标均满足充填的性能要求;固硫灰在化学激发剂的作用下生成了水化硅酸钙凝胶和钙矾石晶体,充填体浸出液的水质良好,均为Ⅱ、Ⅲ级,对地下水质的影响较小。Water glass, anhydrous sodium sulfate and quick lime are used to stimulate the activity of desulphurization ash to prepare a phosphate tailings filling material. The effects of different amounts of quicklime and mass concentration on the bleeding rate, slump, compressive strength, and deformation properties of the filler were discussed. The microstructure composition and morphology of the hardened body at 28 day age of the filler was studied by X-ray diffraction(XRD) and scanning electron microscopy(SEM). The water quality of the filling leachate was analyzed and evaluated by the improved fuzzy comprehensive evaluation method. The results show that when the mass concentration is 66% and the ratio of cement to sand is 1∶1, the content of quicklime increased from 5% to 15%, the slump is reduced to 160 mm, the bleeding rate of slurry is almost zero, the strength of filling material is obviously increased with the increase of quicklime content, the compressive strength is increased to 5.87 MPa at 28 d, the shrinkage deformation is obviously reduced in the dry environment, and all performance indexes meet the filling performance requirements;the desulphurization ash formed hydrated calcium silicate gel and ettringite under the action of a chemical activator, the water quality of the leachate of the filling body is good, all are grades Ⅱ and Ⅲ, the desulphurization ash have little effect on groundwater quality.

关 键 词：固硫灰 磷尾矿 充填体 模糊综合评价法 水质 

分 类 号：TU502[建筑科学—建筑技术科学]