Why is this research needed?

The ambitious target of net zero-carbon emissions by 2050, agreed by the UK and other countries, has now made carbon capture and storage a necessity. Therefore, new methods to capture carbon dioxide are indeed needed to tackle the climate change crisis.

What is this research investigating?

This project investigates a cryogenic carbon capture method that does not require chemicals, is capable of high CO₂ removal levels and delivers a high purity CO₂, which could be further used in the food industry or to produce chemicals. The cryogenic process involves very low temperatures (around -100C or below) that cause CO₂ to freeze on the surface of beads previously chilled.

Crystal growth (or nucleation) and frost growth research has focused on water in moist air or in refrigeration cycles. Thus, there is a lack of fundamental research regarding CO₂ deposition on a cold surface. Therefore, this work will employ for the first time an imaging technique, Electrical Capacitance Tomography (ECT), which enables better understanding of the behaviour of CO₂ frost in a mixture of gases during controlled experiments in a packed column. A cold packed bed will be used as a heat transfer medium and frost capture surface. This work will identify the operating conditions that influence the efficiency of CO₂ removal, such as the effects of initial bed temperature and CO₂ concentration in the flue gas.

What does the research hope to achieve?

Key findings will be used to support a further larger project proposal for an advanced arrangement using a moving bed for continuous operation of the frosting/defrosting process.