温度对煤矸石还原钢渣铁氧化物制备的水淬渣活性的影响  

Effect of Temperature on Activity of Water Quenched Slag Prepared by Reducing Iron Oxide of Steel Slag with Coal Gangue

作　　者：宋强[1] 聂娇 宋甜甜 胡亚茹[1] 邓洋 陈延信[1] 程福安[1] SONG Qiang;NIE Jiao;SONG Tiantian;HU Yaru;DENG Yang;CHEN Yanxin;CHENG Fuan(College of Materials Science and Engineering Xian University of Architecture and Technology,Xi'an 710055,Shaanxi,China;Shaanxi Fuping Eco-cement CO.,LTD.Weinan 711709,Shaanxi,China)

机构地区：[1]西安建筑科技大学材料科学与工程学院,西安710055 [2]陕西富平生态水泥有限公司,陕西渭南711709

出　　处：《硅酸盐学报》2024年第2期522-532,共11页Journal of The Chinese Ceramic Society

基　　金：陕西省科学技术研究计划(2022GY-418,2022KXJ-008,2023GXLH-052);陕西省教育厅重点研发计划(20JY040)。

摘　　要：钢渣中的铁氧化物是影响钢渣粉活性的因素之一。为改善钢渣粉水化活性,实现钢渣和煤矸石协同处置,利用煤矸石中残碳还原和分离出钢渣中的铁,研究了不同温度下煤矸石与钢渣制备的水淬残渣的物相变化以及水化活性。结果表明:提高还原温度,可以显著提高铁的回收率,最高可达94%。还原温度低于1450℃时,水淬残渣中的矿物相主要为钙镁蔷薇辉石和钙铝黄长石。随着温度分别升高到1450℃和1500℃,钙镁蔷薇辉石和钙铝黄长石相消失。此时,水淬残渣主要由玻璃相组成。还原温度升高导致水淬残渣中玻璃相含量增多,胶凝活性增强,掺加高还原温度水淬渣的水泥水化反应累计放热量更大。Introduction Using as supplementary cementitious materials(SCM)is one of the most important research topics in the resource utilization field of steel slag.However,the iron oxide content in steel slag is greater than that of other cementitious materials(i.e.,clinker,granulated blast furnace slag,and fly ash).The solid solution formed by FeO and CaO-MnO-MgO(RO phase),hematite,wustite,Ca_(2)Fe_(2)O_(5)(C_(2)F)and other Fe-bearing phases have little contribution to the activity of ground steel slag.Some researchers use reductants such as H_(2),CO,anthracite,silicon carbide,and carbon powder to reduce iron oxides from molten steel slag into ferroalloys.Aluminosilicate melt is quenched and resultant residual used as SCM.These methods have a challenge of high cost of reducing agents and difficulty in industrial utilization.This paper used residual carbon in coal gangue as a reductant to reduce iron oxides of steel slag.The remaining aluminosilicate was quenched to prepare slag with a high hydration activity,which could achieve the synergistic disposal of two types of industrial solid waste.Methods Based on the chemical composition of steel slag and coal gangue,as well as the fixed carbon content of coal gangue,the amount of coal gangue required for the sufficient reduction of iron oxide in the two raw materials was determined.After mixing ground coal gangue and ground steel slag thoroughly,the mixture was heated to 1200,1300,1350,1400,1450℃ and 1500℃ at 40℃/min in an argon atmosphere(3 L/min),and then quenched with water after holding for 30 min.The resultant strip off iron particles,and the remaining aluminum silicate is called water quenched residue(WQR).The iron recovery rate was determined according to the chemical composition of the WQR.The mineral phases were determined by an X-ray diffractometer(XRD,Rigaku Co.,Japan),and the glass content in water quenched residue was calculated using the Rietveld quantitative analysis method.The paste and mortar samples were prepared by adding 30%(in mass fraction)WQR int

关 键 词：钢渣 煤矸石 碳热还原 水淬残渣 水化活性 

分 类 号：TQ172[化学工程—水泥工业]