油田CO2驱井筒流动热力影响因素分析
2015-10-21郭林林李巧珍徐哲董航吕春柳
郭林林 李巧珍 徐哲 董航 吕春柳



摘 要:目前低渗透油藏多采用CO2驱油,考虑到CO2驱油后,CO2溶于原油混合体系沿井筒流动过程中易发生相变,现有的黑油模型不能对其进行准确的描述。依据质量守恒、动量守恒、能量守恒、多元气液平衡及传热学等理论,建立CO2原油混合体系在井筒流动中的温度、压力耦合模型,编制“井筒流动温度和压力耦合计算软件”,分析了CO2摩尔分数、日产油量及井深对井口采出液温度的影响。结果表明,随着CO2摩尔分数增加,井口采出液温度降低;相同CO2摩尔分数下,随着井深、日产油量的增加,井口采出液温度均表现为逐渐增加的趋势。此外,该软件界面友好,方便现场人员操作,具有一定的工程实际价值。
关 键 词:二氧化碳驱;井筒流动;软件编制;井口采出液温度
中图分类号:TE 357.7 文献标识码: A 文章编号: 1671-0460(2015)06-1402-04
Analysis of Thermodynamic Influential Factors of
Wellbore Flow in Oil Field With CO2 Flooding
GUO Lin-lin1,LI Qiao-zheng1,XV Zhe1,DONG Hang1,LV Chun-liu2
(1. Northeast Petroleum University, Heilongjiang Daqing 163318,China;
2. PetroChina Liaohe Oilfield Company, Liaoning Panjin 124010,China)
Abstract: At present, a lot of low permeability reservoirs use CO2 flooding process. After the CO2 flooding, CO2 dissolved in crude oil blending system is prone to phase transition along the wellbore flow process ,so the existing black oil model can't describe the wellbore flow accurately. In this paper, based on conservation of mass, momentum conservation, energy conservation, multi-component vapor-liquid equilibrium and heat transfer theory, a CO2-oil mixed system temperature-pressure coupling calculation model in the wellbore flow process was developed, and wellbore temperature and pressure coupling calculation software was programmed, effect of CO2 mole fraction, wellbore depth and daily oil production on the temperature of the wellhead produced fluid was analyzed. The results show that, with the increase of CO2 mole fraction, wellhead produced fluid temperature decreases; under the same CO2 mole fraction, with increasing of well depth and daily oil production, wellhead produced fluid temperature shows a gradually increasing trend. In addition, the software has a friendly interface, convenient field operation, has certain practical value in engineering.
Key words: CO2 flooding; Wellbore flow; Software programming ; Wellhead produced fluid temperature
近年來,我国新增中低-特低渗透油藏储量逐年增加,CO2作为一种驱油剂,在低渗透油藏开发中具有明显的增油降水效果。向地层中注入CO2不仅能有效降低原油粘度,减少残余油饱和度,溶解储层中胶质,提高渗透率,而且能有效的减少空气污染,降低温室效应,故应用CO2驱油在低渗透油田有较好的前景[1,2]。国外开展CO2驱油时间较早,早在1950年起许多国家在实验室和现场进行研究,目前已取得较好的成果。国内虽然研究较晚,但已在大庆、吉林、江苏等地开展试验,相关技术有待研究[3]。
国内外对于井筒传热模型均基于Ramey[4]的基础上,对于油井井筒……
