Predicting the fate of CO2 in geological reservoirs for modelling geological carbon storage

预测地质储层中二氧化碳的去向以模拟地质碳储存

基本信息

批准号：
NE/F002645/1
负责人：
Christopher Rochelle
金额：
$ 93.26万
依托单位：
British Geological Survey
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2008
资助国家：
英国
起止时间：
2008 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FF002645%2F1
关键词：
Predicting fate CO2 geological reservoirs

项目摘要

This proposal is to use natural geological examples to evaluate the fate and ultimate safety of disposing of carbon-dioxide deep underground in geological formations. Separation of carbon-dioxide from power station fuels or exhaust products, and the injection and storage of the CO2 underground in geological formations is an economical and practical way for global society to manage energy supplies while transforming to a low carbon economy. The existence of geological sites where natural carbon-dioxide has remained stored for millions of years suggests removal for more than the 10000-year period needed to protect climate maybe practical and safe. However the processes which govern the fate of carbon-dioxide in brine-filled aquifers are complex and to guarantee the safety and efficiency of the storage it is necessary to be able to predict these over the ~ 10000 year storage period, a time much longer than industry currently models reservoir processes. Many of the processes which operate on supercritical or gaseous carbon-dioxide underground may enhance its storage potential. The buoyant CO2 will dissolve in the formation brines to form denser CO2-saturated brine which will sink. The CO2-saturated brine is relatively reactive but current models suggest that the reactions with carbonate and silicate minerals in the reservoir will ultimately lead to a significant proportion of the CO2 being precipitated as carbonate minerals stored permanently. However the CO2-charged brines may also react with the caprocks which retain the carbon-dioxide and it is not known whether this will enhance the seals by mineral precipitation or degrade them by mineral dissolution. A major limitation in our ability to predict these fluid-mineral reactions is that the reactions proceed slowly at variable rates (days or months to many years) and our knowledge of the reaction rates in real field settings is very limited. This project will study fluids and gasses from natural carbon-dioxide reservoirs and, where possible, from sites where carbon dioxide is being actively injected underground, to determine the rates of the mineral-fluid reactions in natural settings. We will duplicate the reactions in laboratory experiments where it will be possible to study the processes under controlled conditions, study individual reactions from the complex set of coupled reactions which take place in the natural rocks and examine the effects of varying potential rate-controlling parameters. The ultimate objective is to inform site assessment, risk and monitoring for geological carbon storage. The research will benefit other areas of the environmental sciences where rates of kinetically-limited fluid-mineral reactions govern important processes.

该提案旨在利用自然地质实例来评估地下深处地质构造中二氧化碳处理的命运和最终安全性。从发电站燃料或废气产品中分离二氧化碳，并将二氧化碳注入地下地质层并储存起来，是全球社会在向低碳经济转型的同时管理能源供应的一种经济实用的方法。天然二氧化碳已储存数百万年的地质遗址的存在表明，保护气候所需的一万年以上的清除时间可能是可行且安全的。然而，控制二氧化碳在充满盐水的含水层中的命运的过程是复杂的，为了保证储存的安全性和效率，有必要能够预测大约 10000 年的储存期，这个时间比工业界目前对油藏过程进行建模。许多在地下超临界或气态二氧化碳上运行的过程可以增强其储存潜力。浮力 CO2 将溶解在地层盐水中，形成密度更大的 CO2 饱和盐水，然后下沉。二氧化碳饱和盐水相对活泼，但目前的模型表明，与储层中碳酸盐和硅酸盐矿物的反应最终将导致很大一部分二氧化碳作为碳酸盐矿物永久储存而沉淀。然而，充有二氧化碳的盐水也可能与保留二氧化碳的盖层发生反应，目前尚不清楚这是否会通过矿物沉淀增强密封性或通过矿物溶解使密封性退化。我们预测这些流体-矿物反应能力的一个主要限制是反应以可变速率（几天或几个月到很多年）缓慢进行，并且我们对实际现场环境中反应速率的了解非常有限。该项目将研究来自天然二氧化碳储层的流体和气体，并在可能的情况下，研究来自地下积极注入二氧化碳的地点的流体和气体，以确定自然环境中矿物流体反应的速率。我们将在实验室实验中复制这些反应，从而可以研究受控条件下的过程，研究天然岩石中发生的复杂耦合反应中的单个反应，并检查不同潜在速率控制参数的影响。最终目标是为地质碳储存的现场评估、风险和监测提供信息。这项研究将有利于环境科学的其他领域，在这些领域中，动力学限制的流体-矿物反应的速率控制着重要的过程。