Department of Environment, Faculty of Forestry and Environment, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
Institute of Tropical Forestry and Forest Products (INTROP), Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
Environ Geochem Health. 2023 Jul;45(7):4439-4460. doi: 10.1007/s10653-023-01513-y. Epub 2023 Feb 22.
Mining activities have often been associated with the issues of waste generation, while mining is considered a carbon-intensive industry that contributes to the increasing carbon dioxide emission to the atmosphere. This study attempts to evaluate the potential of reusing mining waste as feedstock material for carbon dioxide sequestration through mineral carbonation. Characterization of mining waste was performed for limestone, gold and iron mine waste, which includes physical, mineralogical, chemical and morphological analyses that determine its potential for carbon sequestration. The samples were characterized as having alkaline pH (7.1-8.3) and contain fine particles, which are important to facilitate precipitation of divalent cations. High amount of cations (CaO, MgO and FeO) was found in limestone and iron mine waste, i.e., total of 79.55% and 71.31%, respectively, that are essential for carbonation process. Potential Ca/Mg/Fe silicates, oxides and carbonates have been identified, which was confirmed by the microstructure analysis. The limestone waste composed majorly of CaO (75.83%), which was mainly originated from calcite and akermanite minerals. The iron mine waste consisted of FeO (56.60%), mainly from magnetite and hematite, and CaO (10.74%) which was derived from anorthite, wollastonite and diopside. The gold mine waste was attributed to a lower cation content (total of 7.71%), associated mainly with mineral illite and chlorite-serpentine. The average capacity for carbon sequestration was between 7.73 and79.55%, which corresponds to 383.41 g, 94.85 g and 4.72 g CO that were potentially sequestered per kg of limestone, iron and gold mine waste, respectively. Therefore, it has been learned that the mine waste might be utilized as feedstock for mineral carbonation due to the availability of reactive silicate/oxide/carbonate minerals. Utilization of mine waste would be beneficial in light of waste restoration in most mining sites while tackling the issues of CO emission in mitigating the global climate change.
采矿活动常常与废物产生的问题有关，而采矿被认为是一种碳密集型产业，会导致二氧化碳排放到大气中的排放量不断增加。本研究试图通过矿物碳化作用评估将采矿废物再利用为二氧化碳封存的原料的潜力。对石灰石、金矿和铁矿废物进行了废物特性分析，包括物理、矿物学、化学和形态分析，以确定其碳封存潜力。这些样品的特点是碱性 pH 值（7.1-8.3）和含有细颗粒，这对于促进二价阳离子的沉淀很重要。在石灰石和铁矿废物中发现了大量的阳离子（CaO、MgO 和 FeO），分别为 79.55%和 71.31%，这对于碳化过程是必不可少的。已经确定了潜在的 Ca/Mg/Fe 硅酸盐、氧化物和碳酸盐，这通过微观结构分析得到了证实。石灰石废物主要由 CaO（75.83%）组成，主要来源于方解石和硅灰石矿物。铁矿废物由 FeO（56.60%）组成，主要来源于磁铁矿和赤铁矿，以及 CaO（10.74%），主要来源于钙长石、硅灰石和透辉石。金矿废物的阳离子含量较低（总计 7.71%），主要与矿物伊利石和绿泥石-蛇纹石有关。碳封存的平均能力在 7.73%到 79.55%之间，这对应于每公斤石灰石、铁矿和金矿废物潜在封存的 383.41g、94.85g 和 4.72g CO。因此，由于存在反应性的硅酸盐/氧化物/碳酸盐矿物，矿山废物可能被用作矿物碳化的原料。在解决 CO 排放问题以减轻全球气候变化的同时，利用矿山废物将有利于大多数采矿地点的废物恢复。
