The CO2 Capture Project (CCP) has completed the first phase of a study into the impact of CO2 impurities on geological storage of CO2.
The CCP is using reservoir simulation and laboratory experiments to study the potential impacts of impure CO2 streams on storage containment. If it can be shown that impurities do not adversely impact injectivity, conformance or containment it may be possible to deliver less pure CO2 streams to storage resevoirs.
The study is being undertaken in conjunction with the Bureau for Economic Geology. Phase One involved the development of reservoir models to simulate injection and plume migration of CO2 streams from single and non-compressible gas impurities.
The results suggest that long term reliability from CO2 storage seems unlikely to be compromised by the presence of impurities in the CO2 stream – indeed trapping timescales may be reduced in many cases. However, it also seems that the presence of impurities can impact behaviour of the CO2 plume, implying that reservoir modelling for commercial projects needs to factor this in so that the presence of CO2 in reservoirs can be better understood.
The later phases of the study – static experiments and integration – are expected to be completed later this year.