Combined study of static and dynamic reservoir modelling for the CO2 storage project in deep saline aquifer in Zhundong, Xinjiang, China

Geological storage of CO2 has been identified as an effective technology to reduce greenhouse gas emissions and mitigate global climate change. Deep saline aquifers are recognised as having the highest CO2 storage potential. The Junggar Basin is located in the northern Xinjiang and has extensive distributed deep saline aquifers, which could be the effective sites for CO2 storage. CO2 injectivity and storage capacity were investigated through both static and dynamic modelling on the Cretaceous Donggou Formation aquifer in Zhundong area, Junggar Basin. A static reservoir model was constructed by integrating well data and seismic attributes, and the best estimate of storage capacity (P50) was estimated to be approximately 72 million tonnes using a storage coefficient of 2.4% (P50). Dynamic simulation provided a comprehensive understanding of injectivity, storage capacity and explanation of the different storage mechanisms after CO2 injection. The total injection of CO2 was 31.4 million tonnes with five injection wells. Simulations suggest that at year 300 after injection, 28% of the injected CO2 was stored by residual trapping and 26% of the injected CO2 was dissolved into formation water. The modelling results suggest that there is good potential for large scale CO2 aquifer storage in the Junggar Basin.