Enhancing CO_(2)mitigation potential and mechanical properties of shotcrete in underground mining utilizing microbially induced calcium carbonate precipitation  

作　　者：Qiusong Chen Xinyi Yuan Aixiang Wu Yikai Liu 

机构地区：[1]School of Resources and Safety Engineering,Central South University,Changsha 410083,China [2]School of Civil&Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China

出　　处：《International Journal of Mining Science and Technology》2024年第12期1643-1653,共11页矿业科学技术学报（英文版）

基　　金：funded by the National Natural Science Foundation of China(Nos.52274151 and 552104156);the 14th Five Years Key Programs for Science and Technology Development of China(No.2021YFC2900400).

摘　　要：Achieving low-carbon development in the mining sector is fundamental for global carbon emissions abatement,especially considering the growing demand for mineral resources.Currently,the energy foot-print of mines emerges as the main carbon contributor.While cleaner energy sources have the potential for reducing emissions,transitioning to these sources remains challenging.This study presents a practical CO_(2)mitigation strategy for underground mining by integrating bacteria into shotcrete to enhance exca-vation.The findings demonstrate that bacteria can capture CO_(2)from the atmosphere,thereby increasing the carbonation reactions.X-ray diffraction(XRD),scanning electron microscope(SEM)and energy dis-persive spectrometer(EDS)analysis shows the captured CO_(2)present in the forms of calcite,vaterite,and aragonite.The formed carbonates intermingled with the precipitated calcium-silicate-hydrate(C-S-H)at relatively low bacteria additions,densifying the cementitious matrix and improving the mechan-ical properties.However,high bacteria concentrations lead to excess carbonates that consume C-S-H pre-cipitation,counteracting the benefits of carbonation and reducing mechanical strength.Optimal results were achieved with 0.3%bacteria by mass fraction,potentially mitigating 0.34 kg/m^(2)of CO_(2),which is approximately equivalent 567 g of CO_(2)absorbed by 1 g of bacteria based on the effectiveness demon-strated in this study.These findings are crucial for advancing emissions control in mining and supporting climate goals outlined in the Paris Agreement.

关 键 词：Green mining Tunnel support Shotcrete support CO_(2)mitigation BIOMINERALIZATION 

分 类 号：TD803[矿业工程—矿山开采]