Department of Environmental Sciences, Faculty of Environmental Studies, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
Environmental Forensics Research Unit (ENFORCE), Faculty of Environmental Studies, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
Environ Sci Pollut Res Int. 2020 Apr;27(11):12767-12780. doi: 10.1007/s11356-020-07877-3. Epub 2020 Feb 1.
This study highlights the importance of mineralogical composition for potential carbon dioxide (CO) capture and storage of mine waste materials. In particular, this study attempts to evaluate the role of mineral carbonation of sedimentary mine waste and their potential reutilization as supplementary cementitious material (SCM). Limestone and gold mine wastes were recovered from mine processing sites for their use as SCM in brick-making and for evaluation of potential carbon sequestration. Dominant minerals in the limestone mine waste were calcite and akermanite (calcium silicate) while the gold mine waste was dominated by illite (iron silicate) and chlorite-serpentine (magnesium silicate). Calcium oxide, CaO and silica, SiO, were the highest composition in the limestone and gold mine waste, respectively, with maximum CO storage of between 7.17 and 61.37%. Greater potential for CO capture was observed for limestone mine waste as due to higher CaO content alongside magnesium oxide. Mineral carbonation of the limestone mine waste was accelerated at smaller particle size of < 38 μm and at pH 10 as reflected by the greater carbonation efficiency. Reutilization of limestone mine waste as SCM in brick-making exhibited greater compressive strength and lower water absorption compared to the bricks made of gold mine waste. The gold mine waste is characterized as having high pozzolanic behaviour, resulting in lower carbonation potential. Therefore, it has been noticeable that limestone mine waste is a suitable feedstock for mineral carbonation process and could be reutilized as supplementary cementitious material for cement-based product. This would be beneficial in light of environmental conservation of mine waste materials and in support of sustainable use of resources for engineering construction purposes.
本研究强调了矿物成分对于矿山废物潜在二氧化碳（CO）捕集和封存的重要性。特别是，本研究试图评估沉积型矿山废物的矿物碳化作用及其作为补充胶凝材料（SCM）的潜在再利用。从矿山加工场地回收了石灰石和金矿废物，用于砖的制造和潜在碳封存的评估。石灰石矿山废物中的主要矿物为方解石和钙硅石（akermanite），而金矿废物则以伊利石（iron silicate）和绿泥石-蛇纹石（magnesium silicate）为主。石灰石和金矿废物中的氧化钙，CaO 和二氧化硅，SiO，分别具有最高的组成，最大 CO 储存量分别在 7.17 到 61.37%之间。由于较高的 CaO 含量和氧化镁，石灰石矿山废物的 CO 捕集潜力更大。石灰石矿山废物的矿物碳化作用在粒径小于 38μm 和 pH 值为 10 时加速，反映出更高的碳化效率。石灰石矿山废物作为 SCM 在砖制造中的再利用表现出更高的抗压强度和更低的吸水率，与金矿废物制成的砖相比。金矿废物具有较高的火山灰性能，导致较低的碳化潜力。因此，值得注意的是，石灰石矿山废物是一种适合矿物碳化过程的原料，并可作为水泥基产品的补充胶凝材料再利用。这对于矿山废物材料的环境保护和支持工程建设目的的资源可持续利用是有益的。
