Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, USA.
Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, USA.
Sci Total Environ. 2022 Jan 15;804:149985. doi: 10.1016/j.scitotenv.2021.149985. Epub 2021 Sep 4.
Although the world is gradually moving towards renewable energy resources, the coal industry will continue to be a major energy supply sector in the foreseeable future. However, by-products such as coal fly ash (CFA), coal bottom ash (CBA), and boiler slag are generated during coal combustion, and have become a significant environmental concern. There is an urgent need for transdisciplinary efforts in research, policy, and practice to reduce these by-products substantially. Many studies have focused on the environmental management and comprehensive utilization of CFA. As a comparison, less attention has been paid to CBA. Therefore, this critical review provides a holistic picture of CBA, from the generation, fundamental characteristics, environmental concerns to potential applications, and benefits analysis. Based on the fundamental characteristics, CBA can be considered as a sustainable and renewable resource with great potential to produce value-added materials. High-value applications and current research related to CBA, including construction and ceramic industry, wastewater remediation, soil amelioration, energy catalysis, valuable metals recovery, and material synthesis, are systemically presented and compared. It emphasizes the environmental and economic benefits of the sustainable applications of CBA as well. Particularly, it indicates that CBA is a promising candidate in normal, lightweight, self-compacting, and ultra-high-performance concrete, which shows a reduction in both energy consumption and greenhouse gas emissions during concrete production. This work provides new insights into the greener and sustainable applications of CBA, and it will offer a practical guide for the sustainable development of the coal industry.
尽管世界正在逐步向可再生能源资源转型，但在可预见的未来，煤炭行业仍将是主要的能源供应部门。然而，煤炭燃烧过程中会产生煤矸石（CFA）、炉底渣（CBA）和锅炉渣等副产品，这已成为一个重大的环境问题。研究、政策和实践领域急需跨学科的努力，以大幅减少这些副产品。许多研究都集中在 CFA 的环境管理和综合利用上。相比之下，对 CBA 的关注较少。因此，本综述从生成、基本特征、环境问题到潜在应用和效益分析等方面，对 CBA 进行了全面的概述。基于基本特征，CBA 可被视为一种具有巨大增值潜力的可持续、可再生资源。CBA 的高附加值应用和当前研究，包括建筑和陶瓷工业、废水修复、土壤改良、能源催化、有价金属回收和材料合成等，都进行了系统的介绍和比较。文中强调了 CBA 可持续应用的环境和经济效益。特别是，文中指出 CBA 在普通、轻量、自密实和超高强度混凝土中具有广阔的应用前景，这表明在混凝土生产过程中可以减少能源消耗和温室气体排放。这项工作为 CBA 的绿色可持续应用提供了新的见解，并为煤炭行业的可持续发展提供了实用指南。
