深部咸水层CO_2注入能力影响因素分析——以鄂尔多斯盆地石千峰组为例

An analysis of the influence factors on CO_2 injection capacity in a deep saline formation: a case study of Shiqianfeng Group in the Erdos Basin

文章采用井筒-储层耦合模拟方法(T2WELL),以鄂尔多斯盆地石千峰组地层资料为基础,研究井口CO_2注入温度、储层咸水盐度、渗透率和孔隙度等因素变化对注入能力的影响。结果显示,储层渗透率对注入能力的影响最大,温度、咸水盐度影响次之。模拟时间内(20 a)孔隙度的变化对CO_2注入能力影响较渗透率小。通过增大渗透率可以显著提高CO_2注入能力,但渗透率越大,CO_2注入总量随时间增加幅度变小;孔隙度的增加也可提高CO_2注入能力,但是效果远没有渗透率显著;储层咸水的盐度和温度变化与CO_2注入能力的变化呈负相关性。

The sduty of injection capacity of CO2 into saline formations includes CO2 injection rate and injection mass. By employing a newly developed wellbore-reservoir coupled simulator（ T2WELL） and using the data of the Shiqianfeng Group in the Erdos Basin,this paper investigates the effects of CO2 injection temperature at wellhead,salinity of formation water,permeability and porosity on the injection capacity. The simulation results show that the reservoir permeability has a maximum impact on the injection capacity,which is followed by temperature,salinity and porosity. Increasing the permeability will significantly improve the injection capacity,whereas the increasing amplitude will reduce when permeability increases. Increase in porosity can also improve the injection capacity,but the effect is much smaller than permeability. The reversal trends are observed for the cases of salinity and temperature.