[H-SC05] CCUS (Carbon Dioxide Capture, Utilization, and Storage) for Climate Mitigation

[HSC05-P03] A novel technology to active pore space utilization in tight reservoirs

*Ziqiu Xue¹, Hyuck Park² (1.Research Institute of Innovative Tech for the Earth, 2.Geological Carbon Dioxide Storage Technology Research Association)

Microbubble CO2 injection has been carried out at both lab- and field-scale experiments. Visualization of injected CO2 by X-ray CT scanner indicates microbubble CO2 has the advantage in displacing more brine from heterogeneous and low permeability zones because of its small size. This advantage leads to sweep efficiency improvement in geological CO2 and enables us to store more CO2 in geological CO2 and enables us to store more CO2 in same reservoirs compared to conventional CO2 injection as well as economic benefit of achieving higher oil recovery when injecting microbubble CO2 into depleted oil reservoirs.

The high pore space accessibility of microbubble CO2 fits well with practical needs in terms of increased storage capacity as well as enhanced oil recovery. Furthermore, CO2 dissolution into formation water can be accelerated more than 20%, when injecting microbubble rather than conventional CO2 injection into saline aquifers. It will minimize free CO2 fraction in the subsurface as well as formation pressure buildup and consequently contribute to the safety of geological CO2 storage. This advantage has been confirmed from the field-scale microbubble CO2 injection experiments at the JAPEX oil field located in northern Japan (Akita prefecture). This talk will deliver insight gained from both lab- and field-scale microbubble CO2 injections.