自生CO2驱油技术体系及驱油效果研究

Study on authigenic CO2 flooding technology and its effect

宋丹 蒲万芬 徐晓峰 曹建

SONG Dan PU Wan-fen XU Xiao-feng CAO Jian

西南石油学院, 四川 成都 610500 中石化西南局川西采输处, 四川 德阳 618000

针对常规CO2驱存在气源、输送、腐蚀等问题,对自生CO2驱油技术进行了研究。给出了自生CO2驱油机理,在考虑反应速度、经济因素的基础上,筛选出自生CO2体系,对优选出的体系进行原油膨胀、降黏效果评价实验,并利用微观模型和物理模型研究了其驱油机理和效果。实验表明,自生CO2驱油技术在低温时应选用双液法体系,高温选用单液法体系;在一定温度压力条件下,该技术能够使模拟原油膨胀10%~32.5%,油越稠效果越好;可使原油黏度降低38.1%~57.2%;在水驱后能够提高填砂模型采收率6.4~15.5个百分点,双液法效果好于单液法。室内实验和先导性试验表明,自生CO2驱油具有良好的效果,是一种极具潜力的技术。

A study on authigenic CO2 flooding technology is carried out to solve the problem s of natural CO2 sources,transportation,corrosion,etc.in conventional CO2 flooding.This paper presents the authigenic CO2 flooding mechanis mand selects the authigenic CO2 flooding system based on taking reaction speed and economic factors into account. Evaluation is conducted on the effect of the selected CO2 system on expansion viscosity reduction in crude oil. The flooding mechanism and effect of the system is studied by using microscopic models and physical models.The experiment shows that dual hydraulic method is suitable to low temperature and single hydraulic method is suitable to high temperature.The expansion rate of the analog oil ranges from 10% to 32.5% in certain temperature and pressure based on using the authigenic CO2 flooding technology.It functions better as the density of oil increases.What’s more,this technology enables the crude viscosity to reduce by 38.1% to 57.2%.The recovery rate of the sand pack will increase by 6.4% to 15.5% after flooding.Experimental research and pilot tests show that the authigenic CO2 flooding technology perform s w ell and is of great potential for application.

10.3969/j.issn.1000-7393.2007.01.024