基于固废磷石膏制备胶凝材料的工艺与机制
Preparation technology and mechanism of cementitious material based on solid waste phosphogypsum
郑玉龙 1嵇帅 1陆春华 1孙玉涛 1赵航2
作者信息
- 1. 江苏大学 土木工程与力学学院,镇江 212013
- 2. 丹阳市基零佳崮新型建筑材料有限公司,镇江 212300
- 折叠
摘要
大量堆积的工业固废磷石膏对环境造成了严重污染,同时,传统高能耗的水泥产业与实现"双碳"目标的矛盾日渐突出.已有研究表明,基于磷石膏制备的胶凝材料可以部分替代普通硅酸盐水泥,但使用未经处理的原材料时其工作与力学性能较差.本文主要利用原状磷石膏、矿渣、钢渣和石灰石等常见的工业固废材料,制备绿色高强的磷石膏基胶凝材料.研究结果表明,内掺 0.5wt％植物蛋白与胶凝体系中的Ca2+生成螯合物,形成配位化合物覆盖在石膏晶核表面,不仅延缓了胶凝材料的凝结时间,增大了水化反应程度,也提高了其力学性能.通过微观及成分分析表明,磷石膏在胶凝材料中主要作为填充物质,矿渣在钢渣的碱激发作用下发生水化反应,且石灰石在促进水化反应的同时改善了浆体孔结构;基于原状固废磷石膏,采用m磷石膏:m矿渣:m钢渣:m石灰石=0.45:0.35:0.1:0.1配合比制备出的胶砂试件,其28天抗折强度为7.0 MPa、抗压强度为39.1 MPa,软化系数为0.91,接近P·O 42.5级别普通硅酸盐水泥性能.
Abstract
A large amount of industrial solid waste phosphogypsum has caused serious pollution to the environ-ment.At the same time,the contradiction between the traditional cement industry with high energy consumption and the realization of the"double carbon"target has become increasingly prominent.Some studies have shown that the cementitious material based on phosphogypsum can replace part of ordinary Portland cement,but its working and mechanical properties are poor when using raw materials without treatment.In this paper,the green and high strength phosphogypsum based cementitious materials were prepared by using common industrial solid wastes such as original phosphogypsum,slag,steel slag and limestone.The results show that chelates are formed by mix-ing 0.5wt％plant protein with Ca2+in the gelling system to produce a coordination compound covering the surface of gypsum nucleus,which not only delays the setting time of the gelling material,promotes the hydration reaction degree,but also improves its mechanical properties.The microstructure and composition analysis show that phos-phogypsum is mainly used as a filler in the cementitious material,the slag is activated by the alkali of steel slag,and the limestone promotes the hydration reaction while providing Ca2+.Based on the original solid waste phos-phogypsum,using the mixture ratio of mphosphogypsum:mslag:msteel slag:mlimestone = 0.45:0.35:0.1:0.1,28 days flexural strength of mortar specimen is 7.0 MPa,compressive strength is 39.1 MPa,and softening coefficient is 0.91,which is very close to the performance of P·O 42.5 grade ordinary Portland cement.
关键词
固废磷石膏/胶凝材料/植物蛋白/力学性能/凝结硬化机制Key words
solid waste phosphogypsum/cementitious material/plant protein/mechanical properties/setting and hardening mechanism引用本文复制引用
基金项目
国家自然科学基金项目(52108147)
国家自然科学基金项目(51878319)
江苏省博士后科研资助计划(2020Z350)
江苏大学高级人才基金资助项目(20JDG19)
出版年
2024
NETL
NSTL
万方数据