Environmental Geoscience

负排放技术涉及从大气中去除二氧化碳（CO2），对于限制全球变暖和防止气候变化的最严重影响是必要的。在这些技术中，增强岩石风化和二氧化碳矿化旨在加速地球通过化学风化从大气中去除二氧化碳的自然能力，方法是将岩石粉末分散在矿区、农田和林地等大片地区。岩石粉末中的含钙和含镁矿物与大气中的二氧化碳发生反应，将二氧化碳储存在水中和固体碳酸盐中。如果大规模部署，这种方法将提供巨大的捕获和永久储存二氧化碳的能力。然而，在二氧化碳去除速率、碳储存验证、协同效益和环境问题方面存在许多不确定性。该研究计划包括四个相互关联的项目，旨在推进增强岩石风化和二氧化碳矿化，作为可行的减缓气候变化战略。某些矿井产生大量适合清除二氧化碳的矿物废料，并可加以利用。在与采矿业的合作下，将在一个矿场开始一项实地试验，在几年的时间里测量二氧化碳的清除率和核实实际条件下的碳储存。一项免费的实验室研究将检查风化的矿山废物，以了解风化过程以及这些过程如何稳定矿山废物并将其风险降到最低。将在农田和林地使用各种岩石粉末进行增强岩石风化的实地试验。这些试验将用于评估二氧化碳去除，调查土壤-岩石相互作用，并评估潜在的共同利益，如养分释放。此外，补充的实验室实验将研究使用高活性氧化镁和氧化钙粉末去除二氧化碳。应对气候变化需要实施负排放技术，同时大幅减少温室气体排放。该研究计划通过开发新方法、解决不确定性并在大规模上证明其有效性，推进了两项最有前途的技术。加拿大非常适合利用这些方法，因为它有丰富的适合部署的岩石和广阔的土地。

Negative emission technologies involve removing carbon dioxide (CO2) from the atmosphere and are necessary to limit global warming and prevent the worst impacts of climate change. Of these technologies, enhanced rock weathering and CO2 mineralization aim to accelerate Earth's natural ability to remove CO2 from the atmosphere through chemical weathering by dispersing rock powder over large areas such as mine sites, agricultural fields, and forested lands. Calcium- and magnesium-bearing minerals in the rock powder react with atmospheric CO2, storing the CO2 in waters and solid carbonates. This approach offers an enormous capacity to capture and permanently store CO2 if deployed at large scales. However, there are many uncertainties relating to the rates of CO2 removal, verification of carbon storage, co-benefits, and environmental concerns.This research program comprises four interconnected projects that aim to advance enhanced rock weathering and CO2 mineralization as viable climate change mitigation strategies. Certain mines produce large quantities of mineral wastes suitable for CO2 removal and are accessible for deployment. In collaboration with the mining industry, a field pilot will be initiated at a mine site to measure rates of CO2 removal and verify carbon storage under real-world conditions over several years. A complimentary laboratory study will examine weathered mine wastes to understand weathering processes and how these may stabilize mine wastes and minimize their risk.Enhanced rock weathering field trials will be undertaken in agricultural and forested lands using various rock powders. These trials will be used to evaluate CO2 removal, investigate soil-rock interactions, and assess potential co-benefits such as nutrient release. In addition, complementary laboratory experiments will investigate CO2 removal using highly reactive magnesium and calcium oxide powders.Addressing climate change requires implementing negative emission technologies while also drastically reducing greenhouse gas emissions. This research program advances two of the most promising technologies by developing new methodologies, addressing uncertainties, and demonstrating their effectiveness at large scales. Canada is well suited to capitalize on these approaches, given its abundance of suitable rocks and vast lands for deployment.