The influence of alkaline activation on coal gasification slag–MSWI FA based binder and its associated hydration mechanism

IF 7.4 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY Construction and Building Materials Pub Date : 2024-11-12 DOI:10.1016/j.conbuildmat.2024.139112

Yuhang Liu , Siqi Zhang , Wen Ni , Dongshang Guan , Xiang Chen , Tong Zhao , Zeping Wu , Yongchao Zheng

{"title":"The influence of alkaline activation on coal gasification slag–MSWI FA based binder and its associated hydration mechanism","authors":"Yuhang Liu , Siqi Zhang , Wen Ni , Dongshang Guan , Xiang Chen , Tong Zhao , Zeping Wu , Yongchao Zheng","doi":"10.1016/j.conbuildmat.2024.139112","DOIUrl":null,"url":null,"abstract":"<div><div>Solid waste binders have been accepted for their eco-friendliness and good mechanical properties. The effect of alkaline activators on binder hydration process is currently a hot research topic in this field. However, there is a lack of systematic summary and analysis on how to utilize the synergistic cooperation among various ions to promote the hydration reaction. This paper designs a scientific system using the chemical composition from gypsum, municipal solid waste incineration fly ash and steel slag, highlighting the differences of alkaline activations on low-hydration coal gasification slag. Results show that replacing 40 % of blast furnace slag with coal gasification slag increases 28-day strength to 34.86 MPa and 31.00 MPa with 5 % Ca(OH)<sub>2</sub> and 15 % steel slag, respectively, representing gains of 51.4 % and 34.7 %. Conversely, NaOH addition results in a 28-day strength of less than 10.00 MPa, with a 60.9 % decrease at 90 days. The reasons for the heavy weakening (57 %) and enhancement (51 %) of strength are then discussed, summarising the notable differences in alkali cations, hydration mechanism and heavy metal curing mechanism. Finally, a sodium-rich C–N–S–H gel model was constructed with considering the microstructure, hydration products, and temperature. It is expected that this paper can provide a reference for the prospective study of alkaline activation.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"453 ","pages":"Article 139112"},"PeriodicalIF":7.4000,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Construction and Building Materials","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0950061824042545","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}

引用次数: 0

Abstract

Solid waste binders have been accepted for their eco-friendliness and good mechanical properties. The effect of alkaline activators on binder hydration process is currently a hot research topic in this field. However, there is a lack of systematic summary and analysis on how to utilize the synergistic cooperation among various ions to promote the hydration reaction. This paper designs a scientific system using the chemical composition from gypsum, municipal solid waste incineration fly ash and steel slag, highlighting the differences of alkaline activations on low-hydration coal gasification slag. Results show that replacing 40 % of blast furnace slag with coal gasification slag increases 28-day strength to 34.86 MPa and 31.00 MPa with 5 % Ca(OH)₂ and 15 % steel slag, respectively, representing gains of 51.4 % and 34.7 %. Conversely, NaOH addition results in a 28-day strength of less than 10.00 MPa, with a 60.9 % decrease at 90 days. The reasons for the heavy weakening (57 %) and enhancement (51 %) of strength are then discussed, summarising the notable differences in alkali cations, hydration mechanism and heavy metal curing mechanism. Finally, a sodium-rich C–N–S–H gel model was constructed with considering the microstructure, hydration products, and temperature. It is expected that this paper can provide a reference for the prospective study of alkaline activation.

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

碱性活化对煤气化炉渣-MSWI FA 基粘结剂的影响及其相关水化机理

固体废弃物粘结剂因其环保性和良好的机械性能而被广泛接受。碱性活化剂对粘结剂水化过程的影响是目前该领域的研究热点。然而，如何利用各种离子之间的协同作用来促进水化反应，目前还缺乏系统的总结和分析。本文利用石膏、城市固体废弃物焚烧飞灰和钢渣的化学成分，设计了一套科学的体系，突出了碱性活化剂对低水化煤气化渣的作用差异。结果表明，用煤气化炉渣代替 40% 的高炉矿渣，28 天强度分别提高到 34.86 兆帕和 31.00 兆帕，其中 Ca(OH)2 为 5%，钢渣为 15%，分别提高了 51.4% 和 34.7%。相反，添加 NaOH 会导致 28 天强度低于 10.00 兆帕，90 天强度下降 60.9%。然后讨论了强度严重降低（57%）和提高（51%）的原因，总结了碱阳离子、水合机制和重金属固化机制的显著差异。最后，考虑到微观结构、水化产物和温度，构建了富钠 C-N-S-H 凝胶模型。希望本文能为碱性活化的前瞻性研究提供参考。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文去求助

来源期刊

Construction and Building Materials 工程技术-材料科学：综合

CiteScore

13.80

自引率

21.60%

发文量

3632

审稿时长

82 days

期刊介绍： Construction and Building Materials offers an international platform for sharing innovative and original research and development in the realm of construction and building materials, along with their practical applications in new projects and repair practices. The journal publishes a diverse array of pioneering research and application papers, detailing laboratory investigations and, to a limited extent, numerical analyses or reports on full-scale projects. Multi-part papers are discouraged. Additionally, Construction and Building Materials features comprehensive case studies and insightful review articles that contribute to new insights in the field. Our focus is on papers related to construction materials, excluding those on structural engineering, geotechnics, and unbound highway layers. Covered materials and technologies encompass cement, concrete reinforcement, bricks and mortars, additives, corrosion technology, ceramics, timber, steel, polymers, glass fibers, recycled materials, bamboo, rammed earth, non-conventional building materials, bituminous materials, and applications in railway materials.