孔渗非均质性对CO_2羽流地热系统功能影响数值模拟研究  

NUMERICAL MODELING OF THE PERFORMANCE OF THE CO_2-PLUME GEOTHERMAL SYSTEM IN A PERMEABILITY AND POROSITY HETEROGENEOUS RESERVOIR

作　　者：朱慧星[1] 许天福[1] 封官宏[1] 袁益龙 姜振蛟[1] 

机构地区：[1]吉林大学地下水资源与环境教育部重点实验室,长春130021

出　　处：《太阳能学报》2017年第7期1814-1821,共8页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金(41572215;41402205);中国地质调查局地质调查项目(121201012000150011)

摘　　要：以松辽盆地泉头组地层作为研究地层,采用数值模拟的方法分析地层孔渗非均质性对于二氧化碳羽流地热系统的影响。结果表明:由于非均质储层中快速通道的存在,使得在井间距为1000 m,注入压力为16 MPa时,CO_2的产出时间可以由均质储层中的15个月提前到3个月;非均质储层中,CO_2流动集中,储层换热体积减小,产出流体温度下降速率加快;孔渗非均质性既可能引起产出流体温度和系统热提取速率快速下降,也可能导致系统产出流体流量减小,从而使得系统运行期间热提取速率一直偏低。This paper analyzes the influence of permeability and porosity heterogeneity on the CO2-plume geothermal system in the Quantou formation based on numerical simulations. Results suggest that the breakthrough time of the CO2 from injection well to production well in the heterogeneous reservoir can be about 3 months due to the presence of highly conductive zone, which is much earlier than that of 15 months in the homogeneous reservoir in the case which the injector-producer distance is 1000 m and injection pressure is 16 MPa. In such a heterogeneous aquifer, CO2, as a work fluid, has a short time to exchange heat from the reservoir and it＇ s temperature drop rapidly, which is disadvantage to the heat production. Permeability and porosity heterogeneity could lead to the temperature of production liquid and the heat extraction rate dropping quickly or result in the low production rate of liquid and low heat extraction rate.

关 键 词：二氧化碳羽流地热系统 数值模拟 孔渗非均质 井筒储层耦合 

分 类 号：TK52[动力工程及工程热物理—热能工程]