CO2 injection and storage - Short and long-term behaviour at different spatial scales

对能源使用的预测普遍认为，到21世纪下半叶，世界将严重依赖化石燃料。在我们的能源需求能够被替代能源满足之前，人们普遍认为，在枯竭的石油油藏和深层盐碱含水层中进行二氧化碳地质储存，可以提供最有前途和最实用的方法之一，减少发达国家、更重要的是中国和印度等快速发展国家燃烧化石燃料的发电厂的二氧化碳排放。化石燃料发电站碳捕获和封存的二氧化碳排放量估计可减少高达90%。英国政府制定了一个雄心勃勃的目标，到2050年将二氧化碳排放量减少80%，预计碳捕获和封存(CCS)将在实现这一目标方面发挥重要作用。尽管向石油储藏注入二氧化碳已有50多年的历史，以提高石油采收率，但在各国政府承诺达到对二氧化碳排放产生重大影响所需的CCS水平之前，仍有许多不确定性需要解决。许多国家已经开始了大量的研究，以解决这些不确定性。此外，一些二氧化碳储存试点研究已经完成或正在进行，包括在陆上和近海以及在枯竭的油气藏和含盐含水层内。该项目通过综合实验室和数值模拟方法解决了我们在这一领域现有知识中的空白。该项目的主要目标可以概括为：-制定方法，以优化二氧化碳注入井的布置和控制战略，考虑到不确定性和对邻近许可证的影响。-通过实验室和数值研究，确定原地压力和温度条件对盖层裂缝闭合和断层重新激活的影响。-调查和改进我们对现场井筒水泥/岩石和水泥盖层行为的了解，以评估油井的完整性。-利用密封剂和诱导矿物沉淀过程，开发新的井筒和盖层渗漏缓解和补救技术。

Projections of energy usage generally agree that the world will be heavily reliant on fossil fuels well into the second half of the 21st Century. Until our energy demands can be met by alternative sources, geological storage of CO2 in depleted petroleum reservoirs and deep saline aquifers is widely acknowledged to offer one of the most promising and practical means to reduce CO2 emissions from fossil fuel burning power stations in the developed world and more importantly in rapidly developing nations such as China and India. Estimated reductions in CO2 emission from carbon capture and storage from fossil fuel generating stations can be as high as 90%.The UK Government has an ambitious target to reduce CO2 emissions by 80% by 2050, and Carbon Capture and Storage (CCS) is expected to play a major role to meet this target. Although CO2 has been injected into petroleum reservoirs for over 50 years to improve oil recovery, there are still many uncertainties that must be addressed before governments will commit to the level of CCS that is needed to have a significant impact on CO2 emissions. A large amount of research has been initiated in many countries to address these uncertainties. In addition, several CO2 storage pilot studies have been completed or are in progress both on- and off-shore as well as within depleted petroleum reservoirs and saline aquifers. This project addresses the gaps in our current knowledge in this field through an integrated laboratory and numerical modelling approach. The main objectives of the project can be summarised as:- - to develop methodologies to optimise CO2 injection well placement and control strategies accounting for uncertainties and influence on neighbouring licenses. - to establish the effects of in situ pressure and temperature conditions on caprock fracture closure and fault reactivation through laboratory and numerical investigations. - to investigate and improve our understanding of the in situ wellbore cement/rock and cement caprock behaviour in order to assess well integrity. - to develop novel wellbore and caprock leakage mitigation and remediation technologies utilising sealants and induced mineral precipitation processes.