摘要
利用微观可视化实验和岩心驱替实验,研究了碱驱提高稠油采收率的驱油机理。微观实验结果表明,在稠油碱驱过程中,碱液能够渗入原油中,形成外面包含一层油膜的"水柱"和"小水滴",出现液滴流现象。依靠液滴流的高黏度和产生的贾敏效应,可以有效抑制驱替液的指进,从而增大了波及系数,且随着碱浓度的上升,液滴流现象越明显,波及系数就越大。岩心驱替实验结果表明,随着碱浓度增加,采收率增值和压力降均上升,这与微观实验得出波及系数随碱浓度的上升而增大规律相吻合。因此,碱驱液滴流增大波及系数是提高稠油采收率的主要作用机理。
The displacement mechanism of alkaline flooding to enhance the heavy-oil recovery was studied by the microscopic visualiza- tion test and core flooding test. The micromodel test indicated that during alkaline flooding of heavy oil, the alkaline solution could penetrate into crude oil and subsequently form a ＂water column＂ or ＂water droplet＂ coated with oil film, giving a ＂droplet flow＂. Through the high viscosity of ＂droplet flow＂ and the Jamin effect produced thereafter, the fingering of displacement fluid could be significantly inhibited so as to increase the sweep efficiency. With increasing the alkaline concentration, the more frequently the ＂droplet flow＂ phenomenon occurs, the greater the sweep efficiency is. The core flooding result showed that both the oil recovery and the pressure drop of alkaline flooding increased with increasing the alkaline concentration, this is consistent with the rule ob- tained from the micromodel test that the sweep efficiency increases with increasing the alkaline concentration. Therefore, the incre ment of the sweep efficiency due to the ＂droplet flow＂ in alkaline flooding is the main mechanism to enhance the heavy oil recovery.
出处
《石油学报》
EI
CAS
CSCD
北大核心
2012年第4期663-669,共7页
Acta Petrolei Sinica
基金
国家自然科学基金项目(No.51104170)
霍英东教育基金会资助项目(114016)
山东省泰山学者建设工程项目(TS0070704)
中央高校基本科研业务费专项资金(12CX06024A)
中国石油大学(华东)优秀博士学位论文培育计划项目(LW110203A)资助
关键词
稠油
碱驱
液滴流
波及系数
采收率
heavy oil
alkaline flooding
droplet flow
sweep efficiency
oil recovery
