Carbon Capture, Utilisation and Storage

Carbon capture, utilisation and storage (CCUS) is a method of tackling the emissions of carbon dioxide (CO2) and preventing the release of this greenhouse into the atmosphere. 

CCUS allows large scale energy intensive industries (such as steel production, power generation from burning fossil fuels, blue hydrogen production, chemical processing etc.) to reduce their CO2 emissions. The captured CO2 from these processes can be either stored deep below ground for safe and permanent storage or recycled and used to synthesise useful products (e.g. synthetic fuels or polymers) thus giving economic value. 

Scotland’s offshore geology coupled with our existing oil and gas infrastructure provides us with an opportunity to store millions of tonnes of CO2. World-class research into CCUS is under way at ETP universities across Scotland.

Carbon capture and storage involves three distinct operations – CO2 capture, transportation and injection into geological formations for long-term storage. Utilisation of CO2 involves using the captured CO2 directly in a process, or as a feedstock to produce materials and commodities which can be sold at a market value. Researchers at ETP universities across Scotland are engaged in interdisciplinary projects, which feed into efforts worldwide to see CCUS operating at commercial scale.

A pool of expertise and state-of-the-art research facilities are being employed to develop close-to-commercial and next-generation capture materials and processes. Safe and efficient transportation, suitable storage sites, monitoring methods, synthesis and process development of commercial materials and the economics of CCS are also being explored alongside policy, public engagement and the required regulatory framework.

Carbon capture has been operating for several decades in certain sectors, such as natural gas production. Capture methods include the use of chemical solutions, such as amines and ammonia, or solid membranes. Recovery of the CO2 adds to power plant costs and reduces generation efficiency, so ETP researchers are now focusing on improving capture process efficiency and lowering costs. “Green” capture materials are being developed which use less energy and resources. Chemical modelling of capture plants and processes is also under way, including evaluating performance and flexibility.

The transport of large volumes of CO2 from capture plant to storage site will involve compressing the gas to form a supercritical fluid and the development of safe and efficient pipeline networks. Research in this area includes modelling transport networks and leakage scenarios, reducing compression energy requirements and evaluating pipeline sensors and measurement systems. The impact of impurities in the CO2 flow on pipeline integrity is also being assessed.

Selecting the right geological site for CO2 storage is critical to ensure that, firstly, it has adequate capacity and, secondly, CO2 does not leak back into the environment. The development of storage sites must be economically feasible. Research at ETP universities has involved modifying petroleum and hydrocarbon geoscience (from geology and geo-engineering to subsurface fluid flow) and includes borehole design, injection technology, assessing any potential risks posed by multiple users and the equipment and methods needed for long-term monitoring.

Carbon capture and utilisation is the process of using captured CO2 to produce materials and commodities. These can include concrete and aggregates, polymers, chemicals (e.g. olefins, methanol, formic acid), fertilisers and synthetic fuels. Capturing and utilising CO2 allows many processes to significantly reduce their carbon footprint and in some instances be carbon negative. Research at ETP universities are investigating the chemistry and engineering of utilising CO2, and improving efficiencies from captured CO2 to useful products.

The use of CO2 in enhanced oil recovery provides an opportunity to put the gas, captured at facilities fed by fossil fuels, back underground. In order to do so, developers must understand how the CO2 will behave after injection. Laboratory facilities are being used for reservoir modelling, high pressure flow simulation and the evaluation of different injection strategies.

Few commercial-scale CCS projects currently exist and a lack of experience in regulatory matters could delay demonstration and full-scale projects in the UK. ETP researchers have been working with the UK’s Department of Energy and Climate Change, the Scottish Government and others to develop and test guidance for project developers. Work within ETP universities continues on providing analysis for the development of a national regulatory process for CCS.