溶剂蒸气萃取脱沥青的影响因素实验  

Influence factors experiment of deasphalting in solvent vapor extraction

作　　者：李雁鸿 吴永彬[2] 赵法军[3] 刘鹏程[1] 李秀峦[2] 杨森[1] 陈昭[1] 

机构地区：[1]中国地质大学能源学院,北京100083 [2]中国石油勘探开发研究院提高石油采收率国家重点实验室,北京100083 [3]东北石油大学提高石油采收率教育部重点实验室,黑龙江大庆163318

出　　处：《石油学报》2014年第5期935-940,共6页Acta Petrolei Sinica

基　　金：国家重大科技专项(2011ZX05012);中央高校基本科研业务费专项资金项目(2652013094)资助

摘　　要：针对稠油热采后期采收率不断下降的难题,研究利用溶剂蒸气萃取技术改善开发效果。设计了矩形可视化填砂物理模型,采用新疆风城试验区块特稠油为实验油样,利用实际油藏取心对模型进行充填,进行了一系列溶剂蒸气萃取实验,分别研究溶剂类型、操作压力和填砂后渗透率对沥青沉淀的影响。研究发现,相同条件下丙烷作萃取溶剂时比丁烷萃取效果更好;当操作压力为丙烷的饱和蒸气压时,沥青沉淀效果最好,此时溶剂的回采比例最高,溶剂的循环利用也可降低使用成本;操作压力低于饱和蒸气压力时,会降低稠油中溶入的溶剂气量,降低脱沥青效果;在同一丙烷的饱和蒸气压力下,当渗透率达到几百个达西时,沥青沉淀会使稠油黏度下降,流动性增强,从而提高采油速度;当渗透率比较低时,沥青沉淀会堵塞部分孔隙,对稠油的流动造成一定影响,导致采油速度降低。Thermal recovery of heavy oil is challenged by constantly declining recovery in the late stage. Solvent vapor extraction （VAPEX） is employed to improve the deasphalting process of heavy oil. A rectangular visual sand filling physical model is designed, with extra-heavy oil in Fengcheng oilfield as sample oil. A series of VAPEX tests are conducted by filling the designed model with actual reservoir core in the oilfield. Results are analyzed to assess the effects of solvent type, operating pressure and sand filling permeability on asphaltene precipitation from heavy oil samples. Under the same conditions, solvent extraction with propane produces better results than butane extraction. At the vapor pressure of propane, the effect of asphaltene precipitation is best while the recovery of solvent is largest, thereby reducing the cost via solvent recycling. At the pressure lower than vapor pressure of propane, the volume of solvent dissolved in oil is reduced, negatively affecting the deasphalting of heavy oil. At the same vapor pressure of propane, when the permeability is high of several hundreds of Darcy, asphaltene precipitation can reduce heavy oil viscosity and increase oil fluidity, thereby improving oil recovery rate; when the permeability is lower, asphaltene precipitation may cause partial plugging of pores and pose certain influence on oil fluidity, thereby reducing oil recovery rate.

关 键 词：溶剂蒸气萃取 沥青沉淀 溶剂类型 操作压力 填砂渗透率 

分 类 号：TE345[石油与天然气工程—油气田开发工程]