CO_2在原油中的扩散及引起的沥青质沉积  

Diffusion of CO_2 in Crude Oil and Asphaltene Deposition

作　　者：端祥刚[1] 侯吉瑞[1] 赵凤兰[1] 徐宏明[1] 郭萍[1] 徐海霞[1] 

机构地区：[1]中国石油大学(北京)提高采收率中心,北京102249

出　　处：《油田化学》2011年第4期410-413,共4页Oilfield Chemistry

基　　金：国家自然科学基金"CO2在多孔介质中扩散规律的影响因素及机理研究"(项目编号50804052)

摘　　要：CO2在原油中扩散和溶解,使得原油体积膨胀和黏度降低的同时,原油组分也发生变化,可能引起沥青质等重有机质沉积,伤害储层,因此需全面评价CO2在原油中的扩散和影响因素以及可能引起的沥青质沉积程度。用压力降落法测定了压力和沥青质含量对CO2在原油中的扩散系数和溶解度的影响。结果表明,随着压力增加,CO2在原油中的扩散系数成线性增加,溶解度先增加后降低。随原油沥青质含量的增加,CO2扩散系数降低,溶解度增加。CO2扩散后的原油沥青质含量大幅降低,最高降幅达94.6%,表明CO2在扩散过程中引起了沥青质的沉积。The diffusion and dissolved of CO2 in crude oil made the volume of oil expand,the viscosity decrease,and the oil composition change,which might lead to asphaltene deposition,and result in formation damage.So the influencing factors of CO2 diffusion and the level of asphaltene deposition should be evaluated totally.The diffusion coefficient and solubility of CO2 in crude oil under different pressures and asphaltene content were measured by pressure reducing curve method.The results showed that when the pressure increased,the diffusion coefficient of CO2 increased linearly,but the solubility increased firstly and then reduced.The diffusion coefficient of CO2 decreased,while the solubility increased with increasing content of asphaltene.The greatly decrease of asphaltene content after CO2 diffusion with the maximum reduction up to 94.6%,which showed that the diffusion process of CO2 led to the deposition of asphaltene.

关 键 词：二氧化碳 原油 压力 沥青质 扩散系数 溶解度 沉积 

分 类 号：O645.12[理学—物理化学] O645.14[理学—化学]