Hydration and Pb Stabilization Mechanisms of Fly Ash–Slag-Based Mine Backfilling Binders

IF 2.6 4区 环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES
Chutong Zhao, Xiaona Wang, Yi Rao, Chunjiang Yu, Zhongli Luo, Jia Li, Amirhomayoun Saffarzadeh, Chuanfu Wu, Wen Ni, Qunhui Wang
{"title":"Hydration and Pb Stabilization Mechanisms of Fly Ash–Slag-Based Mine Backfilling Binders","authors":"Chutong Zhao, Xiaona Wang, Yi Rao, Chunjiang Yu, Zhongli Luo, Jia Li, Amirhomayoun Saffarzadeh, Chuanfu Wu, Wen Ni, Qunhui Wang","doi":"10.1007/s41742-024-00642-1","DOIUrl":null,"url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>To completely replace Portland cement for mine backfilling, MSWI fly ash (FA) and solid metallurgical wastes (ground granulated blast furnace slag, steel slag and flue gas desulphurisation gypsum) were used to prepare fly ash-slag-based binder (FBB). The effect of FA content on the hydration and Pb stabilization mechanisms of the FBB was investigated. When a small amount (15%) of FA was added to FBB, hydration product formation and compressive strength were inhibited during early curing (7 d). However, the additional Ca<sup>2+</sup>, SO<sub>4</sub><sup>2−</sup> and OH<sup>−</sup> carried by FA could partially promote the formation of ettringite, so that the compressive strength of 28 d was comparable to that of the treatment without FA addition (32.5 MPa). When a high amount of FA (30%) was added, the hydration process was strongly inhibited throughout the entire curing period, and the leaching concentration of Zn (1052 μg/L) exceeded the limits of the GB/T 30760–2014 standard (1000 μg/L). Pb<sup>2+</sup> was also found to replace Ca<sup>2+</sup> in ettringite to form insoluble Pb-ettringite and Pb<sub>2</sub>(SO<sub>4</sub>)O precipitates, resulting in remarkable Pb stabilisation in system. Therefore, if the amount of FA incorporated is appropriate, the use of FA as an additional cementitious material for mine backfilling is an ideal method for recycling FA.</p><h3 data-test=\"abstract-sub-heading\">Graphical Abstract</h3>","PeriodicalId":14121,"journal":{"name":"International Journal of Environmental Research","volume":"145 1","pages":""},"PeriodicalIF":2.6000,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Environmental Research","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1007/s41742-024-00642-1","RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0

Abstract

To completely replace Portland cement for mine backfilling, MSWI fly ash (FA) and solid metallurgical wastes (ground granulated blast furnace slag, steel slag and flue gas desulphurisation gypsum) were used to prepare fly ash-slag-based binder (FBB). The effect of FA content on the hydration and Pb stabilization mechanisms of the FBB was investigated. When a small amount (15%) of FA was added to FBB, hydration product formation and compressive strength were inhibited during early curing (7 d). However, the additional Ca2+, SO42− and OH carried by FA could partially promote the formation of ettringite, so that the compressive strength of 28 d was comparable to that of the treatment without FA addition (32.5 MPa). When a high amount of FA (30%) was added, the hydration process was strongly inhibited throughout the entire curing period, and the leaching concentration of Zn (1052 μg/L) exceeded the limits of the GB/T 30760–2014 standard (1000 μg/L). Pb2+ was also found to replace Ca2+ in ettringite to form insoluble Pb-ettringite and Pb2(SO4)O precipitates, resulting in remarkable Pb stabilisation in system. Therefore, if the amount of FA incorporated is appropriate, the use of FA as an additional cementitious material for mine backfilling is an ideal method for recycling FA.

Graphical Abstract

Abstract Image

粉煤灰-矿渣型矿山回填粘结剂的水化和铅稳定机理
摘要 为了完全替代硅酸盐水泥用于矿山回填,采用了 MSWI 粉煤灰(FA)和固体冶金废物(磨细高炉矿渣、钢渣和烟气脱硫石膏)来制备粉煤灰-矿渣基粘结剂(FBB)。研究了 FA 含量对 FBB 的水化和铅稳定机制的影响。当向 FBB 中添加少量(15%)FA 时,水化产物的形成和抗压强度在早期固化(7 d)期间受到抑制。然而,FA 所携带的额外 Ca2+、SO42- 和 OH- 可部分促进乙长石的形成,因此 28 d 的抗压强度与未添加 FA 的处理结果(32.5 MPa)相当。当添加高量(30%)的 FA 时,整个固化期的水化过程都受到强烈抑制,Zn 的浸出浓度(1052 μg/L)超过了 GB/T 30760-2014 标准(1000 μg/L)的限制。此外,还发现 Pb2+ 在埃特林岩中取代 Ca2+ 形成不溶性的 Pb- 埃特林岩和 Pb2(SO4)O 沉淀,使体系中的 Pb 显著稳定。因此,如果掺入适量的 FA,将 FA 用作矿山回填的附加胶凝材料是一种理想的 FA 循环利用方法。
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 求助全文
来源期刊
CiteScore
5.40
自引率
0.00%
发文量
104
审稿时长
1.7 months
期刊介绍: International Journal of Environmental Research is a multidisciplinary journal concerned with all aspects of environment. In pursuit of these, environmentalist disciplines are invited to contribute their knowledge and experience. International Journal of Environmental Research publishes original research papers, research notes and reviews across the broad field of environment. These include but are not limited to environmental science, environmental engineering, environmental management and planning and environmental design, urban and regional landscape design and natural disaster management. Thus high quality research papers or reviews dealing with any aspect of environment are welcomed. Papers may be theoretical, interpretative or experimental.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信