Mechanochemical processing of silicate rocks for direct carbon capture (MACO2)

该项目旨在开发一种新技术，将碳捕获到废石粉中，这些粉末是在采矿和骨料生产操作中自然形成的。我们的目标是利用岩石粉碎过程中发生的机械力化学反应，永久捕获工业废气中的二氧化碳，作为一种碳捕获手段。在破碎过程中，当岩石中的化学键断裂时，能量会瞬间释放(作为带电粒子和光子)。我们使用这种机械力化学能量来捕获二氧化碳。我们最近在《自然可持续发展》杂志上发表的研究表明，如果你在二氧化碳气体而不是空气中粉碎富含二氧化硅的岩石，如花岗岩和玄武岩，二氧化碳可以通过化学吸附过程永久地困在粉碎颗粒的晶格中。这个项目将建立在我们早期研究的基础上。我们将探索温度、破碎颗粒大小和初始岩石水分含量对单位碎石质量捕获的二氧化碳总量的影响。我们还将调查气流的组成。我们之前的研究使用了纯二氧化碳：在这里，我们将在水泥生产、生物质发电、天然气和天然气制氢等行业的真实富含二氧化碳的废气中粉碎岩石。我们将使用生命周期分析来评估我们的技术所节省的碳。最后，我们将探索(1)将最终的岩粉用作部分水泥替代产品的可能性，以及(2)从富含二氧化碳的岩粉中联合生产有价值金属的可能性。这项研究项目可能会对我们在2050年前实现净零碳目标的能力产生重大影响。在全球范围内，每年至少有400亿吨富含硅酸盐的岩石被采矿和采石业粉碎。如果我们能用很少的额外能源消耗(除了用于运输二氧化碳的能源)，调整目前的岩石破碎过程来捕获二氧化碳，那么这就可以用来捕获“难脱碳”行业的温室气体。根据我们发布的早期研究结果，每100公吨可销售的碎石至少可以捕获0.4公吨热稳定和不溶的二氧化碳。我们估计，如果这项技术在全球范围内开发和采用，它可以捕获全球约0.5%的二氧化碳排放，或每年175 MtCO2：这相当于一片德国大小的成熟森林捕获的二氧化碳。

This project aims to develop a new technology for capturing carbon into waste rock powders that are naturally formed during mining and aggregate production operations. We aim to use mechanochemical reactions, which occur during rock crushing, to permanently trap CO2 from industrial exhaust gases as a means of carbon capture. During crushing, energy is instantaneously released (as charged particles and photons) when the chemical bonds in the rock are broken. We use this mechanochemical energy to trap CO2. Our recent research, published in Nature Sustainability, showed that if you crush silica-rich rocks, such as granite and basalt, in CO2 gas instead of air, the CO2 can become permanently trapped, via a process of chemical sorption, within the crystal lattice of the crushed particles. This project will build on our early research. We will explore the effects of temperature, crushed particle size and initial rock water content on the amount of CO2 trapped per unit mass of crushed rock. We will also investigate gas stream composition. Our previous research used pure CO2: here we will crush rocks within realistic CO2-rich effluent gases from industries such as cement production, biomass power production, gas and hydrogen production from natural gas. We will evaluate the carbon savings from our technology using life cycle analysis. Finally, we will explore the potential for (1) the final rock powders to be used as a partial cement replacement product, and (2) co-production of valuable metals from the CO2-rich rock powders. This research project could have a major impact on our ability to meet net zero carbon targets by 2050. Worldwide, at least 40 billion tonnes of silicate-rich rocks are crushed every year by the mining and quarrying industries. If we can adapt current rock crushing processes to trap CO2, with very little extra energy expenditure (other than that used to transport the CO2), then this could be used to trap greenhouse gases from 'hard to decarbonise' industries. Based on our published early research findings, at least 0.4MtCO2 of thermally-stable and insoluble CO2 can be trapped for every 100Mt of saleable crushed aggregate. We estimate that, if this technology was developed and adopted worldwide, it could capture ~0.5% of global CO2 emissions, or 175MtCO2 annually: this is equivalent to the CO2 trapped by a mature forest the size of Germany.