水泥基材料中重金属的来源及其对水化性能的影响  

Sources of heavy metals in cementitious materials and their effects on hydration properties

作　　者：王云飞 陈德鹏[1] 郭明磊 吕忠[1] WANG Yunfei;CHEN Depeng;GUO Minglei;LYU Zhong(Civil Engineering and Architecture,Anhui University of Technology,Maanshan 243032,China)

机构地区：[1]安徽工业大学建筑工程学院,安徽马鞍山243032

出　　处：《功能材料》2025年第2期2219-2228,共10页Journal of Functional Materials

基　　金：国家重点研发计划(2021YFB3802005)。

摘　　要：水泥窑协同处置技术伴随绿色低碳高质量发展战略的进行被广泛应用,但废弃物中的重金属会导致使用水泥窑协同处置技术所生产的水泥重金属含量超过规范限值。水泥窑协同处置水泥熟料中常见重金属有Zn、Cu、Cr、Pb、Ni和Cd,其含量总和一般为0.16‰~1.03‰,占混凝土总引入量的95%以上。混凝土中的重金属主要以离子态和金属难溶物两种形态存在,会被C—S—H凝胶、AFm和AFt等水化产物以封裹、吸附和离子替代等形式固化。Zn、Cu、Cr、Pb、Ni和Cd等重金属会提高水泥生料的易烧性,并改变水泥熟料的矿物组成比例,Zn、Cu和Cd会导致水泥熟料中硅酸钙矿相生成更多的C_(3)S,而Cr会促进C_(2)S的生成。重金属在水泥熟料内的固溶情况也不同,Zn会优先固溶在方镁石之中,Cu和Ni主要分布在中间矿物相,Cd和Pb在C_(3)S、C_(2)S、C_(3)A和C_(4)AF上为较均匀的分布,Cr主要分布在C_(2)S中。Cu、Cr、Pb、Ni和Cd可以加速水泥水化热的释放从而促进水泥早期水化,但Zn会与OH^(-)反应生成难溶物覆盖在水泥颗粒表面阻碍水泥早期水化反应;同时常见重金属会与水泥浆体中的OH^(-)发生反应,造成水泥基材料的力学性能的下降。目前已有重金属对水泥基材料的烧制、水化和力学性能影响趋于完善但耐久性影响方面研究较少有待进一步探究。The cement kiln co-disposal technology is widely used in line with the green,low-carbon and high-quality development strategy,but the heavy metals in the waste lead to the production of cement with heavy metal content far exceeding the regulatory limit by the cement kiln co-disposal technology.The common heavy metals in the collaborative disposal of cement clinker in cement kilns include Zn,Cu,Cr,Pb,Ni,and Cd,with a total content generally ranging from 0.16‰to 1.03‰,accounting for more than 95%of the total introduction of concrete.Heavy metals in concrete exist in the form of ionic state and metal insoluble substances,which are fixed in the form of encapsulation,adsorption and ion replacement by C-S-H hydration products such as C-S-H gel,AFm and AFt.Heavy metals such as Zn,Cu,Cr,Pb,Ni,and Cd can increase the burnability of cement raw materials and alter the mineral composition of cement clinker.Zn,Cu,and Cd can lead to the formation of more C_(3)S in the calcium silicate mineral phase of cement clinker,while Cr can promote the formation of C_(2)S.The distribution of heavy metals within the cement clinker is also distinct.Zn primarily dissolves in periclase,while Cu and Ni are predominantly found in intermediate mineral phases.Cd and Pb are uniformly distributed among C_(3)S,C_(2)S,C_(3)A,and C_(4)AF,while Cr is predominantly found in C_(2)S.Cu,Cr,Pb,Ni,and Cd can accelerate the release of cement hydration heat and promote early hydration of cement,but Zn reacts with OH^(-)to form insoluble substances that cover the surface of cement particles,hindering early hydration reactions of cement.At the same time,common heavy metals react with OH^(-)in cement paste,causing a decrease in the mechanical properties of cement-based materials.At present,the effects of heavy metals on the firing,hydration,and mechanical properties of cement-based materials are becoming more comprehensive,but there is less research on the durability impact that needs further exploration.

关 键 词：重金属 水泥基材料 熟料组成 水化特性 

分 类 号：T52[一般工业技术]