碱渣复合胶凝材料制备无熟料混凝土  

Preparation of clinker-free concrete by using soda residue composite cementitious material

作　　者：徐东 倪文[2,3] 汪群慧[1,3] 许成文 姜瑶琪[2,3] XU Dong;NI Wen;WANG Qunhui;XU Chengwen;JIANG Yaoqi(School of Energy and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing Key Lab of Resource-Oriented Treatment of Industrial Pollutants(University of Science and Technology Beijing),Beijing 100083,China)

机构地区：[1]北京科技大学能源与环境工程学院,北京100083 [2]北京科技大学土木与资源工程学院,北京100083 [3]工业典型污染物资源化处理北京市重点实验室(北京科技大学),北京100083

出　　处：《哈尔滨工业大学学报》2020年第8期151-160,共10页Journal of Harbin Institute of Technology

基　　金：国家重点研发计划(2018YFC1900603);国家自然科学基金重点项目(41430106)。

摘　　要：碱渣作为氨碱法制备纯碱过程中产生的固体废弃物,目前无较好的大规模处理利用方法.本文以最大限度利用碱渣为目的,利用碱渣、矿渣、钢渣和脱硫石膏为复合胶凝材料,铁尾矿砂和废石为骨料制备无熟料混凝土.胶凝材料中碱渣掺量30%、矿渣45%、钢渣15%、脱硫石膏10%时,无熟料混凝土的28 d抗压强度可达38.33 MPa.通过XRD、SEM-EDS、TG-DSC和IR等表征方法研究了复合胶凝材料体系的水化产物及水化过程,结果表明该复合胶凝材料的水化产物主要为C-S-H凝胶、钙矾石(AFt)和Friedel盐(FS).对碱渣、矿渣、钢渣和脱硫石膏4种固废之间的协同反应机理进行分析,阐述了水化产物的生成过程.对全固废混凝土做耐久性分析发现,混凝土抗冻性及抗碳化性能良好,但干燥收缩性能和抗硫酸盐侵蚀性能不佳.分析了碱渣无熟料混凝土的制备条件、应用方向和应用前景,为固体废弃物的无害化和资源化利用提供科学依据.Soda residue is the solid waste generated during the ammonia-soda process for soda ash,while there is no effective treatment and utilization disposal method.In order to maximize residue utilization,soda residue,blast furnace slag,steel slag,and desulfurization gypsum were used as composite cementitious material,and iron tailing sand and waste rock were used as aggregate to prepare clinker-free concrete.Results show that by mixing 30%soda residue,45%blast furnace slag,15%steel slag,and 10%desulfurization gypsum,the 28-day compressive strength of the clinker-free concrete could reach up to 38.33 MPa.Hydration products and hydration process of the composite cementitious material were studied through XRD,SEM-EDS,TG-DSC,and IR,and results show that the hydration products of the composite cementitious material were mainly C-S-H gel,ettringite(AFt),and Friedel’s salt(FS).The synergistic reaction mechanism between the raw materials was analyzed to further understand the formation process of the hydration products.Moreover,durability analysis of all-solid waste concrete demonstrates that the concrete had good frost and carbonation resistance,while its dry shrinkage resistance and sulfate attack resistance were poor.Finally,the preparation conditions,application scope,and application prospects of the soda residue clinker-free concrete were analyzed,which provides an in-depth scientific basis for the harmless and resource utilization of soda residue.

关 键 词：碱渣 矿渣 全固废混凝土 水化机理 协同利用 固废资源化 

分 类 号：X705[环境科学与工程—环境工程]