| INORGANIC MATERIALS AND CERAMIC MATRIX COMPOSITES |
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| State-of-the-art Utilization of Coal Gangue in Civil Engineering Materials |
| LIU Ze1,*, DUAN Kairui1, ZHOU Mei2, ZHANG Haibo3, LUO Shuqiong3, FANG Kuizhen1, WANG Dongmin1
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1 School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
2 School of Civil Engineering, Liaoning Technical University, Fuxin 123000, Liaoning, China
3 School of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, Henan, China |
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Abstract As an important member of coal-based solid waste, the appropriate utilization of coal gangue has always been a hotspot issue. During the past decades, the utilization efficiency of coal gangue in China has been greatly improved as the relevant theory and technology developed rapidly, which leads to a successful transformation of coal gangue from so-called ‘waste to treasure’ in many fields, such as energy, chemical, and civil engineering. In particular, civil engineering has become a vital way that can not be ignored for the tremendous consumption of coal gangue, because of its large demand for raw materials and the advanced ‘co-disposal of multiple solid wastes’ technology. This paper reviews the latest research progress of coal gangue as cementitious material/SCM/aggregate in cement, mortar, concrete, geopolymer, road enginee-ring, underground engineering, etc. The technical points, barriers, quality-control measurements, and modification methods are summarized and compared when coal gangue is used in different roles in construction materials. However, some valuable resources in coal gangue are usually ignored when the coal gangue is applied as building materials. Besides, the long-term durability of gangue structures and monitoring of potential environmental risks also need to be carried out. In conclusion, considering the physical and chemical properties of coal gangue, utilization technology level, experience, policy support, and other regionalized factors, raw coal gangue used for preparing various types of building materials still lack a clear and standardized classification management and graded disposal method that is tailored to local conditions in their production. The development, improvement, and organic combination of ‘multi-field technology-standards-policies’ is the key to the establishment of an efficient and orderly gangue building materials market and industry chain in the future.
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Published: 25 May 2024
Online: 2024-05-28
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| Fund:National Natural Science Joint Foundation of China (U20A20324) and Central Universities Outstanding Youth Team Project of CUMTB(2023YQTD03). |
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2024, Vol. 38 
