摘要
针对国外Y油田异常高压且原油具有挥发性的特点,设计正交试验方案,利用数值模拟软件,优化和评价注采参数。首先对储层原油的PVT性质进行拟合,并模拟注气膨胀试验,分析和研究产出气、N2、CO2对原油相态和物理性质的影响;然后,根据正交试验的原理设计试验方案,以采出程度和换油效率为评价指标,对关井气油比、回注压力时机、注气速度、CO2与N2的比值以及井底压力5个参数进行优化研究,并采用极差分析和方差分析对结果进行评价。模拟结果表明,当注入气摩尔分数为40%时,产出气、N2和CO2分别使原油体积膨胀了1.72,1.85,1.42倍,黏度分别变为初始黏度的0.68,1.85,0.82倍;最优注采参数是关井气油体积比为3 000,注入压力时机为45 MPa,注入气量为1.5倍,CO2和N2的比例为4∶1,生产井井底流压为30 MPa。
The overseas Y oilfield is an abnormal high pressure volatile reservoir. To optimize and evaluate its parameters for hydrocarbon miscible displacement,in this paper,we designed some numerical orthogonal experiments and made use of numerical simulation software. Firstly,the PVTi module of Eclipse is used to simulate the gas-injection expansion experiments and analyze the effects of injected gas（ produced gas,N2 and CO2） on the phase behavior of crude oil. Then,according to the experimental results,recovery factor and oil exchange efficiency are used as the criterions to evaluate five injection and production parameters,including shut- in gas oil ratio,injection pressure opportunity,gas injection rate,the rate between CO2 and N2,and production well bottom pressure.The results show that when the mole fraction of dissolved gas reaches 40%,the oil relative volumes of production gas,N2 and CO2increase to 1. 72 times,1. 85 times,and 1. 42 times respectively. Meanwhile,the viscosities increase by 0. 68 times,1. 85 times and 0. 82 times. The optimal combination of parameters are as the following： the shut- in gas oil ratio is 3 000; injection pressure opportunity is 45 MPa; gas injection rate is 1. 5; the rate between CO2 and N2is 4∶ 1,and production well bottom pressure is 30 MPa.
出处
《重庆科技学院学报（自然科学版）》
CAS
2015年第5期94-98,共5页
Journal of Chongqing University of Science and Technology：Natural Sciences Edition
基金
国家自然科学基金项目"超低渗透油藏注气提高采收率理论与技术研究"(U1262101)
关键词
正交试验
PVTi
注气参数
数值模拟
orthogonal experiments
PVTi
gas injection parameters
numerical simulation
