Carbon fingerprint test developed

A new method that is claimed to inexpensively monitor the safe storage of industrial greenhouse gas emissions is to be used at a $5mn carbon capture and storage (CCS) test site in Alberta, operated by Carbon Management Canada. The test is reportedly able to determine the source of a carbon dioxide (CO₂) sample by analysing its chemical fingerprint, and will be used to aid the development of CCS technology in which CO₂ from power stations and industrial sites is securely held underground.

Researchers from the University of Edinburgh developed the test by showing that the chemical fingerprint of CO₂ captured from power plants remains recognisable after it is injected underground. This enables stored industrial CO₂ to be distinguished from other sources of CO₂, such as groundwater or natural emissions from plants and bacteria. 

The team verified the method by studying the chemical fingerprint of CO₂ from experimental storage sites in Australia and Canada. They sampled gas before and after its injection into underground storage and found that the fingerprints remained identifiable. They also found that changes to the fingerprints during storage gave insights into behaviour of the CO₂ underground.

In the same study, samples from CO₂ from industrial sites and power plants around the world revealed how the chemical signature of CO₂ varies with the source of the emissions, such as coal, gas or biomass. 

The research, published in the International Journal of Greenhouse Gas Control, was supported by the Engineering and Physical Sciences Research Council.

Dr Stephanie Flude, of the University of Edinburgh’s School of GeoSciences, who led the study, says: ‘The chemical fingerprint of captured CO₂ varies depending on the capture technology used. This will be useful for tracking CO₂ injected into storage sites and means that in most cases there is no need to add expensive artificial tracers.’

Dr Stuart Gilfillan, also of the School of GeoSciences and study co-ordinator, adds: ‘Our study paves the way for inexpensive monitoring of CO₂ underground for safe, secure storage. We look forward to working with Carbon Management Canada in applying our findings at the new Canadian CCS test site, which will demonstrate the exciting methods we have developed.’