A Dynamic Assessment Of CO₂ Sequestration Potential Through CO₂-EOR In The Beijing-Tianjin-Hebei Region

The Beijing-Tianjin-Hebei region has rich carbon sources and suitable reservoirs for storage.It has the basic conditions for the development of CO₂ enhanced oil recovery（CO₂-EOR）and CO₂ storage,but its development potential needs to be further evaluated.From the perspective of the assessment objects,although there are literature studies on the CO₂-EOR and sequestration potential of the Bohai Bay Basin and regions around the Beijing-Tianjin-Hebei region,there are no research results targeting the Beijing-Tianjin-Hebei region.From the perspective of assessment methods,similar studies are mainly based on geological sequestration potential.The shortcomings of these studies are:first,the lack of technical and economic feasibility demonstration cannot provide a direct basis for the formulation of planning and policies;second,the impact of internal and external changes in the process of industrial development on CO₂-EOR and sequestration potential is ignored,which will underestimate the development potential of CO₂ sequestration.In particular,the promotion of the"Double Carbon"target will have an important impact on CO₂-EOR and CO₂ sequestration,and the impact process is also dynamic.Based on the above reasons,this study was conducted on the dynamic assessment of CO₂ sequestration potential through CO₂-EOR in the Beijing-Tianjin-Hebei region.Firstly,based on the CO₂-EOR and sequestration mechanisms and the characteristics of reservoirs in the Beijing-Tianjin-Hebei region,148 reservoir blocks suitable for CO₂-EOR were screened out,and the geological storage capacity was assessed by analogy.Subsequently,in view of the feedback relationship between increased oil,carbon storage and cumulative net benefit,the evaluation model was built based on the system dynamics model,and the dynamic impact of environmental changes on decision-making behavior was integrated into the system model with the help of cost-benefit analysis.Finally,the sensitivity analysis of scenario factors is carried out by using the model.Three variables,such as carbon storage subsidy,technological progress,and carbon trading market,are screened out,so as to construct pessimistic,benchmark and optimistic scenarios.In the three scenarios,the dynamic CO₂ sequestration potential through CO₂-EOR at different oil price levels is evaluated.The assessment results show that the capacity of CO₂-EOR and geological storage in the Beijing-Tianjin-Hebei region,that is,the upper limit,increased oil by 55.1109 million tons and carbon storaged by 275.5548 million tons respectively,while the dynamic potential expanded with the increase of oil prices.Moreover,the higher the oil price level,the smaller the gap in dynamic potential between different scenarios.For example,when the oil price is$40/barrel,the dynamic potential of the three scenarios is 52.37%,66.82%and 82.19%of the geological storage capacity,respectively,and when the oil price is$60/barrel,it is 82.19%,85.74%and 89.64%,respectively.It suggests that the higher the oil price level,the smaller the impact of other scenario factors,and when oil prices are high enough,the influence of other factors can be ignored.It can be seen that the impact of oil prices should be fully considered in the formulation of CO₂-EOR planning and related policies.