Sustainable Urban Carbon Capture: Engineering Soils for Climate Change (SUCCESS)

我们发现，城市土壤比农业土壤是更有效的碳汇。城市土壤通常携带着来自长期拆迁的细粒材料。这些材料包括含有硅酸钙矿物的水泥粉尘，以及石灰(氢氧化钙)。我们发现，从这些矿物中提取的钙与溶液中的碳酸盐迅速结合，而碳酸盐最终来自两种来源--植物或雨水。这一过程发生的速度非常快，通常每公顷地面每月从大气中去除100吨二氧化碳；这相当于一个足球场大小的一小块地面。由于这一过程，城市土壤中储存的碳量约为每公顷300T C(而农业土壤为每公顷175T C)，拆迁后(在极短的几年内)很快就能实现这一目标。我们希望确保建筑活动利用这些发现，帮助补偿燃烧化石燃料产生的二氧化碳排放，并为英国雄心勃勃的减排目标做出贡献。潜力是存在的-如果从战略上和系统地设计工程土壤具有碳捕获功能，我们相信英国2011年约10%的二氧化碳排放可以通过这种方式被捕获，作为正常建筑活动的一部分。所涉及的成本远远低于固定在特定工厂(如发电站)上的能源和资本密集型二氧化碳洗涤系统。更重要的是，该设计涉及一系列生态系统服务，并涉及拓宽“碳捕获花园”的概念，我们发现这一概念在广泛的利益相关者中非常可接受，因为社区可以享受和参与到令人愉快的空间中。拟议的研究旨在解决一些重要问题：1)我们能否人工复制土壤碳化过程，以便我们能够确定碳捕获价值？2)我们如何验证该过程，以便碳固定的说法可以得到信任？3)该过程是否真的值得进行，在英国和全球二氧化碳减排目标的背景下？4)这一过程对土壤有什么影响，特别是它们排水雨水的强度和能力，从而防止洪水？5)这种方法对动植物群落有什么影响？我们想要的植物会在经过优化碳捕获处理的土地上生长吗？6)这一过程如何与影响棕地场地的现有法规相适应？7)考虑到材料可获得性的地理控制，在什么情况下这一过程在经济上是可行的？8)个人可以在自己的花园中使用这种方法吗？在项目期间，我们将与广泛的利益相关者合作，从工业界、地方当局、环境组织以及学者。我们将让学生参与监测工作，作为传播过程的一部分。所有的工作将以适当的形式公开发布，我们希望建立一个与该项目相关的日益增长的社区网络。

We have found that soils in cities are more effective sinks for carbon than agricultural soils. Urban soils typically carry a burden of fine-grained materials derived from often a long history of demolition. These materials include cement dust, which contains calcium silicate minerals, and also lime (calcium hydroxide). What we have found is that calcium derived from these minerals combines rapidly with carbonate in solution, which ultimately is derived from two sources - plants or rainwater. The rate at which this process occurs is extremely rapid, typically 100 T CO2 are removed from the atmosphere for each hectare of ground monthly; that's in a patch of ground the size of a football pitch. The amounts of carbon stored in urban soils as a consequence of this process are around 300 T C per hectare (compared with 175 T C per hectare in agricultural soils), and this is achieved rapidly after demolition (within very few years).We want to make sure that construction activity takes advantage of these findings, to help compensate for the CO2 emissions that arise from burning fossil fuels, and to contribute to the UK's ambitious targets for reducing our emissions. The potential is there - if engineered soils are strategically and systematically designed to have a carbon capture function we believe that around 10% of the UK's 2011 CO2 emissions could be captured in this way, as part of normal construction activity. The costs involved are far less than energy and capital intensive CO2 scrubbing systems that are fixed to specific plant, such as a power station. What's more, the design involves a range of ecosystem services and involves broadening the concept of 'Carbon Capture Gardens', which we have found to be very acceptable among a wide range of stakeholders, as pleasant spaces are created that communities can enjoy and engage with.The proposed research is intended to address some significant questions:1) Can we reproduce the soil carbonation process artificially, so we can be sure of the carbon capture value?2) How can we validate the process, so that claims of carbon sequestration can be trusted?3) Is the process genuinely worth doing, in the context of UK and global CO2 emissions reduction targets?4) What effect does the process have on soils, especially their strength and ability to drain rainwater, thus preventing flooding?5) What effect does this approach have on plant and animal communities? Will the plants that we want grow in ground that has been treated to optimize carbon capture?6) How does this process fit in with existing regulations that affect brownfield sites?7) Under what circumstances is the process economically viable, given the geographical controls on availability of materials?8) Can individuals use this approach in their own gardens?During the project, we will work with a wide range of stakeholders, from industry, local authorities and environmental groups as well as academics. We will engage students in monitoring work as part of the dissemination process. All the work will be openly published in appropriate forms, and we expect to build a growing community network associated with the project.