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，在21世纪下半叶，世界将严重依赖化石燃料。在我们的能源需求可以被替代资源满足之前，在枯竭的石油储层和深层含盐含水层中地质储存二氧化碳被广泛认为是减少发达国家，尤其是中国和印度等快速发展的国家燃烧化石燃料的发电站排放二氧化碳的最有前途和最实用的方法之一。据估计，化石燃料发电站的碳捕获和储存可减少高达90%的二氧化碳排放。英国政府有一个雄心勃勃的目标，到2050年将二氧化碳排放量减少80%，而碳捕集与封存（CCS）预计将在实现这一目标方面发挥重要作用。尽管50多年来，人们一直在向油藏中注入二氧化碳以提高石油采收率，但在政府承诺CCS水平对二氧化碳排放产生重大影响之前，仍有许多不确定因素必须解决。为了解决这些不确定因素，许多国家开展了大量研究。此外，在陆上和海上以及在枯竭的石油储层和含盐含水层内已经完成或正在进行几项二氧化碳储存试验研究。该项目通过综合实验室和数值模拟方法解决了我们目前在这一领域的知识差距。该项目的主要目标可以概括为：考虑到不确定性和对邻近许可证的影响，开发方法来优化CO2注入井的布置和控制策略。-通过实验室和数值研究，确定原位压力和温度条件对盖层裂缝闭合和断层再激活的影响。-调查并提高我们对原位井眼水泥/岩石和水泥盖层行为的理解，以评估井的完整性。-开发利用密封剂和诱导矿物沉淀过程的新型井眼和盖层泄漏缓解和修复技术。

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.