含钙镁煤基固废CO_(2)矿化封存及其产物性能研究进展

Research progress on CO_(2)mineralization of coal-based solid waste containing calcium and magnesium and its product performance

随着化石碳资源的过度消耗,导致CO_(2)等温室气体的大量排放,全球气候变化已经成为全人类面对的重大挑战之一,同时,煤炭资源开发利用过程中会产生大量的粉煤灰、脱硫石膏等含钙镁煤基固废。如何实现CO_(2)高效捕集与封存是当下面临的极具挑战性课题,粉煤灰、煤气化灰渣等大宗重污染工业固废的大规模综合利用仍亟待突破。在“双碳”目标下,利用煤基固废矿化封存CO_(2)是一项具有巨大潜力的高效应对全球变暖的策略,利用含钙镁煤基固废进行矿物碳酸化对于二氧化碳捕集与封存(CCS)以及固废的资源化处置都具有很大前景。然而,它的工业应用瓶颈依旧无法突破。综述了以典型煤基固废粉煤灰(FA)、脱硫石膏(FGDG)以及煤气化灰渣(CGS)为原料的CO_(2)矿化技术的发展现状,旨在探讨其技术局限性的原因。首先,简要阐述了煤基固废CO_(2)矿化的途径,揭示了煤基固废CO_(2)矿化反应过程和原理。其次,重点讨论了典型煤基固废的矿化潜力和工艺,明晰CO_(2)矿化过程中工艺参数对产物性能的调控机理。最后,总结了煤基固废CO_(2)矿化产物的性能并且利用全生命周期评估(Life Cycle Assessment,LCA)阐明矿化工艺的可行性及其对环境的影响。研究将对煤基固废CO_(2)矿化的工艺技术提供优化建议,以期推动煤炭工业的低碳转型战略目标。

With the overconsumption of fossil carbon resources,resulting in a large amount of CO_(2)and other greenhouse gas emissions,caused by global climate change has become one of the major challenges facing all mankind.At the same time,the development and utilization of coal resources will produce a large amount of coal-based solid wastes containing calcium and magnesium,such as fly ash,desulfurization gypsum and other solid wastes.How to realize efficient CO_(2)capture and sequestration is a very challenging issue nowadays,as well as the large-scale comprehensive utilization of fly ash,coal gasification slag,and other large-scale heavy polluting industrial solid wastes is still in need of a breakthrough.Under the goal of“double carbon”,CO_(2)mineralization from coal-based solid waste is a potential strategy to effectively address global warming,and mineral carbonation of coal-based solid wastes containing calcium and magnesium has great prospects for carbon dioxide capture and sequestration(CCS)as well as for the resource-based disposal of solid waste.However,the industrial application bottleneck of CO_(2)mineralization in coal-based solid waste is still unable to break through.This paper reviews the current development of CO_(2)mineralization from fly ash(FA),desulfurization gypsum(FGDG),and coal gasification slag(CGS),with the aim of exploring the reasons for their technical limitations.Firstly,this paper briefly elaborates on the pathways for CO_(2)mineralization of coal based solid waste,revealing the reaction process and principles of CO_(2)mineralization of coal based solid waste.Secondly,the miner-alization potential and process of typical coal-based solid waste were summarized and compared to clarify the mechanism of the regula-tion of the process parameters on the product properties during CO_(2)mineralization process.Finally,the performance of CO_(2)mineraliza-tion products from coal-based solid waste was summarized,and the feasibility of the mineralization process and its environmental impact were elucidated using a Life Cycle Assessment(LCA).This paper will provide optimization suggestions on the process technology of coal-based solid waste CO_(2)mineralization to promote the strategic goal of low-carbon transformation in the coal industry.