CO_2深部盐水层地质封存成本研究

Cost Analysis of CO_2 Geological Storage in Deep Saline Formation

为进一步完善CCS经济可行性研究以及封存场地优选,从全生命周期的角度建立了深部盐水层(DSF)封存成本的工程经济模型。该模型在前人研究成果基础上,将注入前场地检查成本、注入后监测及设备处置成本纳入考虑范围。以典型DSF封存场地为例,计算得出CO2均化封存成本为4.89$/t,其中注入成本占80.43%,监测成本、场地勘察及检查成本分别占10.46%和9.12%。在此基础上,探讨了年注入量、储层渗透率、储层压力、储层孔隙度、储层厚度及储层深度6个因素变动对均化封存成本的影响,总结了其变化规律,并从注入井数量和封存场地面积两个方面进行了解释。通过敏感性分析得出,储层深度和储层压力对均化封存成本的影响最大,储层厚度和储层孔隙度次之。

In order to study the relationship between the deep saline formation（DSF） storage cost and the reservoir properties and the location for the CO2 storage, an engineering economic model of the DSF storage cost is established in this paper. Compared with the conventional studies, this model takes into account the costs of the old well review and the post-injection monitoring, focusing more on the leakage and pollution prevention. Taking a typical scenario as an example, the total capital cost is calculated as 76.86×106$, the total annual operation and maintenance cost is 5.03×106$/a, and the levelized cost of the DSF storage is 4.89 $/t. In the levelized cost, the injection related cost, the monitoring related cost and the site characterization related cost account for 80.43%, 10.46% and 9.12%, respectively. The relations among the levelized storage cost, the injection rate, and the reservoir properties such as the permeability, the pressure, the porosity, the thickness and the depth are also analyzed. It is shown that the levelized cost decreases with the increase of the permeability, the thickness and the porosity of the reservoir. On the other hand, however, the relations between the injection rate, the reservoir pressure and the reservoir depth are more complex, they are non-monotonous. These relations are explained from the aspects of the number of the injection wells and the area of the storage site. Finally, through the sensitivity analysis, the reservoir depth and the reservoir pressure are found to be the most sensitive factors to the levelized cost.