增强硅酸盐岩风化——“碳中和”之新路径

Enhanced Silicate Rock Weathering——A New Path of “Carbon Neutrality”

自工业革命以来,人类活动向大气排放了大量的CO_(2),使得全球地表温度快速上升,为应对全球变暖,人类有必要大规模应用负排放技术。增强硅酸盐岩风化是一种基于地球化学原理的负排放技术,该技术旨在通过向农田或森林中添加硅酸盐岩粉末,加速硅酸盐岩的化学风化过程,以在较短时间内固定更多的大气CO_(2)。中国玄武岩储量丰富且分布广泛,并有大量未利用的矿山尾矿和碱性硅酸盐废料,因此通过增强硅酸盐岩风化去除大气CO_(2)的潜力很大。研究结果显示中国每年可通过增强硅酸盐岩风化去除0.13~0.80 Gt CO_(2),有助于我国“碳中和”目标的实现,但目前增强硅酸盐岩风化仍面临诸多问题。结合国内外研究进展,总结了增强硅酸盐岩风化主要的应用效果和影响因素,对我国应用增强硅酸盐岩风化的潜力进行了分析,并从技术、经济、安全、社会和政策5个方面探讨了我国应用增强硅酸盐岩风化面临的主要问题。针对目前研究的热点与不足,对增强硅酸盐岩风化固碳量的计算及其应用的潜在危害性等需要重点关注的内容和面临的挑战进行了展望。

Since the industrial revolution,human activities have emitted large amounts of CO_(2)into the atmosphere,causing a rapid increase in global surface temperatures.To cope with global warming,it is necessary to apply negative-emission technologies on a large scale.Enhanced silicate Rock Weathering(ERW)is a form of negative-emission technology based on geochemical principles that accelerates the chemical weathering process of silicate rock by adding silicate rock powder to farmland or forests to stabilize atmospheric CO_(2)over a short time period.China has abundant and widely-distributed basalt reserves and a large amount of unused mine tailings and alkaline silicate wastes.Therefore,there is great potential for the removal of atmospheric CO_(2)through ERW.The calculation results show that China can remove 0.13~0.80 Gt CO_(2)through ERW annually,which is conducive to the realization of the“carbon neutrality”goal.However,ERW still faces many problems.Combining the progress of domestic and international research,the main application effects and influencing factors of ERW are summarized,the potential of ERW application in China is analyzed,and the main issues facing ERW application in China are discussed from five aspects:technology,economy,safety,society,and policy.In view of the focus and shortcomings of the current research,the calculation of ERW carbon sequestration,potential hazards of application,and other key concerns and challenges are presented.