煤矸石在土木工程材料中的应用研究进展

State-of-the-art Utilization of Coal Gangue in Civil Engineering Materials

煤矸石作为煤基固废系列的重要成员,其资源化利用一直是煤基固废的热点研究方向。多年来,在研究人员和工程技术人员的共同努力下,我国煤矸石资源化利用技术水平与利用效率均得到大幅提升,在多个领域(能源、化工、土木工程)成功实现了煤矸石“由废变宝”的转化过程。特别地,土木工程材料领域兼具“大体量”特点和“多元固废协同处置”等技术优势,成为大宗消纳煤矸石的中坚领域。本文综述了煤矸石作为胶凝材料/辅助胶凝材料和骨料在水泥混凝土、地质聚合物、道路工程及地下工程等方向的最新研究进展,总结并对比了煤矸石用作不同组分时的技术要点、难点及对应的质量控制措施和改性增强手段等。然而,矸石建材化的同时也容易导致矸石内部的“有价资源”未得到充分利用;矸石构筑物的长期耐久性和环境影响监测等工作也亟待补充。综上,受煤矸石理化性质、矸石资源化利用技术水平、经验及政策扶持力度等区域化差异因素的影响,煤矸石原料在用于多类型建材制品的生产过程中依然缺少因地制宜、明确且规范的分类管理和分级处置方法,“多领域技术-规范-政策”的逐步发展、完善和有机结合是今后建立高效有序的矸石建材市场及产业链的关键所在。

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.