Developing a cost-effective and robust monitoring, measurement, and verification program for Carbon Capture and Sequestration

Project Highlights:

• Cutting-edge research with tremendous environmental and societal implications.
• Develop geophysical methods for state-of-the-art seismic surveying equipment.
• Use of state-of-the-art geophysical equipment and data.
• Train as a geophysical specialist for a carbon neutral future.

Background

As early as the late 19th century, a link between carbon dioxide (CO2) and temperature in the atmosphere was suspected (Arrhenius, 1896; Chamberlin 1899). During the 20th century this link was further studied and by the beginning of the 21st century there is no doubt that global warming is due to human activity (Lynas et al., 2021). Anthropogenic CO2 has thus far contributed to a global temperature rise of 1 °C, increasing with 0.2 °C per decade following current trends (IPCC, 2021). Carbon Capture and Storage (CCS) is a promising process to combat the increasing concentration of CO2 in the atmosphere. From 2020 to 2021, the capacity of CO2 sequestration from CCS projects grew from 75 million tonnes per annum (year) (Mtpa) to 111 Mtpa in 2021 (Global CCS Institute, 2021).

For a CCS project to be considered as having a successful mitigation on the effects of climate change, it is proposed that CO2 emissions to the atmosphere should be less than 0.01% (Hepple & Benson, 2004) or even 0.001% (Shaffer, 2010) of the total injected volume. Every active CCS project must have a robust monitoring, measurement, and verification (MMV) program in place, that aims to meet 3 monitoring objectives (Furre et al, 2017): conformance, containment, and contingency monitoring.

A wide range of geophysical measurements, such as seismic, well logging, gravity surveys, and tiltmeters and interferometric synthetic aperture radar (InSAR) for surface deformation measurements, can be used to design a robust MMV program. Seismic waves contain information about both the sources of seismic energy (earthquakes, roads, cities, ocean waves, wind, etc) and the structure and properties of the Earth. By studying seismic waves recorded by dense arrays of sensors, we can construct 3D images of the subsurface. Monitoring changes over time allow to observe and interpret Earth processes that change the subsurface. This is important both for natural hazard assessment (e.g. volcanic monitoring), monitoring effects of climate-change (e.g. glacial melting), or monitoring of subsurface-related industrial activity such as geothermal energy production and waste storage.

Time-lapse monitoring is a tested and trialled technology commonly used in oil and gas production. Despite step-change innovations during the last decade, in the areas of compressive sensing, seismic inversion, and machine learning, practices of seismic surveying for time-lapse monitoring have not changed. However, the cost-benefit for CCS is drastically different, requiring ground-up redevelopment of acquisition and processing practices. This forms a formidable barrier to CCS projects, because regulators are expected to require extensive monitoring during CO2 injection, and for several decades after CO2 injection ceases, to detect undesirable plume migration and any developing pathways of leakages. Furthermore, the subsurface near prospective CO2 storage reservoirs is often relatively well known from decades of oil and gas exploration, accompanied by detailed seismic surveying. This spurs the question of whether the data requirements for monitoring could be substantially relaxed.

Aims and objectives

During this project, you will develop cost-effective geophysical methodologies for an effective and robust monitoring, measurement, and verification (MMV) program. The specific deliverables can be agreed based on your specific interests and expertise. Example objectives that may be explored as part of the project:

1. Which geophysical measurements (or attributes) are most sensitive to a particular leakage scenario.
2. How to design an optimal survey for an MMV program given a particular target.
3. How to adapt an MMV program dynamically based on detected changes.

Full scale CCS project

As part of the Danish strategy to decrease the CO2 emission by 70% compared to 1990 level and become zero emitter by 2050 there is a increasing push towards CCS since these goal cannot be achieved otherwise. The Danish government has recently announced that they will support a full-scale CCS project with 1 billion £. Gas Storage Denmark operate a gas reservoir and plan as part of this project to inject 4 Mt over the next decade. As this is one of the first full scale point to point CCS projects in Europe it will be of paramount importance that the CO2 is contained within the reservoir. Therefore, extensive monitoring during CO2 injection and for at least 50 years thereafter is required. At present it is not decided which monitoring techniques that will be used. Since the CO2 injection site will also serve as a pilot where different monitoring methods can be used and tested, there is as part of this PhD project an opportunity to influence this strategy and development.

Training

The student will work principally under the supervision of Dr Sjoerd de Ridder (School of Earth and Environment), an expert in seismic imaging and inversion. Co-supervisors include Dr Roger Clark and Dr Mikael Lüthje, who are experts in near-field geophysical testing methods, observational seismology, software development, and geophysical inversion. The student will benefit from access to, and the relevant training with, Leeds’ sector-leading inventory of seismic survey equipment. The project provides specific training in:

1. Developing theory suitable for processing and interpreting new types of geophysical datasets.
2. State of the art seismic source and sensor technology.
3. Numerical and computational techniques (e.g. modelling, optimisation).

Research at Leeds

The PhD student will work with experts in this field of research and will be part of the Applied Geophysics research group of the Institute of Applied Geosciences (School of Earth and Environment) of the University of Leeds: the UK’s largest industry facing geoscience institute with application and impact towards energy, environmental, industrial, and infrastructural problems. Leeds Earth Sciences is ranked 23^rd worldwide in the ShanghaiRanking, and 96% of our selected research is considered world leading or internationally excellent in the REF 2021. We have a diverse research base, strong international profile and are highly multi-disciplinary, with access to state-of-the-art high performance computing facilities at Leeds. The PhD student will benefit from working within a supportive research group as well as from training at the university and the industry. The PhD student will be able to attend national and international conferences and workshops.

Applicant Profile

You will have a strong numeric background (e.g. geophysics, physics, computer sciences, engineering). You should have a passion for new geophysical theory and methods to push the boundaries of subsurface investigation with environmental/economic implications to benefit society. A competence with programming languages (e.g., Matlab, Python, etc) is also desirable. Finally, with the global reach of this research, you will be encouraged to present at international conferences.

References & Further Reading

Don Lawton (2010); Carbon capture and storage: opportunities and challenges for geophysics. Recorder, vol. 35, Issue, no. 06.

Fawad, M., N. H. Mondol (2011). Monitoring geological storage of CO2: a new approach. Scientific Reports, volume 11, 5942.

Leung et al., (2014). An overview of current status of carbon dioxide capture and storage technologies. Renewable and Sustainable Energy Reviews, V 39, Pages 426-443

Oldenburg, Curtis & M, Curtis. (2022). Health, Safety, and Environmental Screening and Ranking Frameworkfor Geologic CO2 Storage Site Selection. 10.2172/885235.