四川盆地理论CO_2地质利用与封存潜力评估

结合CO_2地质利用与封存技术机理,在国际权威潜力评估公式的基础上,系统地提出了适合中国地质背景的次盆地尺度CO_2封存潜力评估方法及关键参数取值。同时,以四川盆地为例,依次开展了枯竭油田地质封存与CO_2强化石油开采、枯竭气田与CO_2强化采气、不可采煤层地质封存与CO_2驱替煤层气,以及咸水层地质封存技术的CO_2地质封存潜力。结果表明,四川盆地利用深部咸水层与枯竭天然气田CO_2地质封存潜力最大,期望值分别达154.20×10~8t和53.73×10~8t。其中,枯竭天然气田因成藏条件好、勘探程度高、基础建设完善,为四川盆地及其周边利用枯竭气田CO_2地质封存技术实现低碳减排提供了早期示范机会。CO_2地质利用与封存潜力评估方法,对进一步开展全国次盆地尺度理论封存潜力评估与工程规划具有重要意义。

Theoretical potential assessment of CO2 geological utilization and storage in the Sichuan Basin

Based on the mechanism of CO₂ geological utilization and storage technologies and the international authoritative evalua-tion formulae, the methodology of theoretical potential assessment at the sub-basin scale is proposed in this paper, and the solutions of key parameters are provided.Meanwhile, with the Sichuan Basin as a case study, the theoretical potential of depleted oil CO₂ storage and CO₂-EOR, depleted gas CO₂ storage and CO₂-EGR, unmineable coal bed seams CO₂ storage and CO₂-ECBM, and deep saline aquifer CO₂ storage are evaluated respectively.The results show that the total CO₂ storage potential of deep saline aquifers and depleted gas fields CO₂ storage could reach 154.20×10⁸t and 53.73×10⁸t on the average.Because of good traps, high degree of exploration and good infrastructures, depleted gas fields provide a great chance for carrying out demonstration or industrial CO₂ geological storage proj-ects first for the CO₂ resources located in the Sichuan Basin.The methodology of potential assessment of CO₂ geological utilization and storage technologies has great exploring significance for sub-basin scale national potential evaluation and project planning in China.