Wellbore Pressure and Temperature Prediction Model and Its Affecting Factors for CO2 Injection Wells
-
摘要: 为了提高注CO2驱替效率及驱替成功率,开展了影响驱替效率的井筒压力温度分布及影响因素研究。针对CO2特殊的物理性质,选用基于赫姆霍兹自由能的Span-Wagner状态方程,将井筒传热、压力与CO2物性参数耦合迭代计算,建立了注CO2井筒温度压力分布的数学预测模型。该模型能够预测井筒温度压力及其他物性参数,应用该模型预测井筒各点温度压力,并与江苏草舍油田草8井现场2次实测结果对比,其温度误差均小于1%,压力最大误差不超过1.6%,表明该模型能够满足现场应用要求。利用该模型可以研究注入温度、注入压力、注入速度及注入时间等工艺参数对井底压力温度的影响规律,实现系统敏感性分析。研究表明,建立的模型具有很高的精度,对提高CO2驱替效率具有指导作用,并适用于(超临界)CO2钻井、压裂过程中井筒温度压力预测及影响因素分析。Abstract: In order to improve the displacement efficiency and success rate of CO2 flooding,research has been carried out to predict the pressure and temperature distribution in the wellbore,which affects the displacement efficiency.In view of the special physical properties of CO2,Span-Wagner equation of state,based on the dimensionless Helmholtz energy,has been adopted to establish a model to predict the distribution of temperature and pressure while injecting CO2,calculated by iterative coupling with CO2 physical parameter and pressure as well as heat.The model can predict the bottomhole temperature and pressure accurately.Compared with the well site data of Well Cao 8 in Jiangsu Oilfield,the error of predicted temperature less than 1%,and the maximum error of pressure less than 1.6%,it can meet the requirements of field application.Moreover,the sensitivity analysis can be done through the research of effecting regularity on the bottomhole pressure and temperature produced by injection temperature,injection pressure,injection rate and time,etc.Study shows that model is very accurate,and it can guide CO2 flooding,fit for prediction and analysis of wellbore temperature,pressure and related affecting factors in supercritical CO2 drilling and fracturing.
-
Keywords:
- CO2 injection /
- state equation /
- well bore flow /
- pressure /
- temperature
-
-
[1] Abdassah D,Siregar S.The potential of carbon dioxide gas injection application in improving oil recovery[R].SPE 64730,2000.
[2] 何应付,高慧梅,周锡生.改善特低渗透油藏注二氧化碳驱油效果的方法[J].断块油气田,2011,18(4):512-515. He Yingfu,Gao Huimei,Zhou Xisheng.Study on method for improving displacement effect of CO2 drive in extra-low permeability reservoir[J].Fault-Block Oil Gas Field,2011,18(4):512-515. [3] 国殿斌,房倩,聂法健.水驱废弃油藏CO2驱提高采收率技术研究[J].断块油气田,2012,19(2):187-190. Guo Dianbin,Fang Qian.Nie Fajian.Study on EOR of injection CO2 for waterflooding abandoned reservoir[J].Fault-Block Oil and Gas Field,2012,19(2):187-190. [4] 吴晓东,王庆,何岩峰.考虑相态变化的注CO2井井筒温度压力场耦合计算模型[J].中国石油大学学报:自然科学版,2009,33(1):73-77. Wu Xiaodong,Wang Qing,He Yanfeng.Temperature-pressure field coupling calculation model considering phase behavior change in CO2 injection well borehole[J].Journal of China University of Petroleum:Edition of Natural Science,2009,33(1):73-77. [5] 王庆,吴晓东.CO2注入井井筒温度压力剖面计算及影响因素研究[J].科学技术与工程,2009,9(18):5330-5334. Wang Qing,Wu Xiaodong.Study on temperature and pressure profiles and its influencing factors in CO2 injection wellbore[J].Science Technology and Engineering,2009,9(18):5330-5334. [6] Paterson L,Lu M,Connell L,et al.Numerical modeling of pressure and temperature profiles including phase transitions in carbon dioxide wells.SPE 115946,2008.
[7] Yasunami T,Sasaki K,Sugai Y.CO2 temperature prediction in injection tubing considering supercritical condition at Yubari ECBM pilot-test[J].Journal of Canadian Petroleum Technology,2010,49(4):44-50.
[8] 张勇,唐人选.CO2井筒压力温度的分布[J].海洋石油,2007,27(2):59-64. Zhang Yong,Tang Renxuan.Study of distribution of wellbore pressure and temperature of CO2 injection well[J].Offshore Oil,2007,27(2):59-64. [9] Hasan A,Kabir C.Aspects of wellbore heat transfer during two phase flow.SPE 22948,1994.
[10] Chen N.An explicit equation for friction factor in pipe[J].Industrial and Engineering Chemistry Research Fundamentals,1979,18(3):296-297.
[11] Span R,Wagner W.A new equation of state for carbon dioxide covering the fluid region from the triple-point temperature to 1100 K at pressures up to 800 MPa[J].Journal of Physical and Chemical Reference Data,1996,25(6):1509-1596.
[12] 邱正松,谢彬强,王在明,等.超临界二氧化碳钻井流体关键技术研究[J].石油钻探技术,2012,40(2):1-7. Qiu Zhengsong,Xie Binqiang,Wang Zaiming,et al.Key technology on drilling fluid of super critical carbon dioxide[J].Petroleum Drilling Techniques,2012,40(2):1-7. [13] Fenghour A,Wakeham W.The viscosity of carbon dioxide[J].Journal of Physical and Chemical Reference Data,1998,27(1):31-43.
[14] Vesovic V,Wakeham W,Olchowy G,et al.The transport properties of carbon dioxide[J].Journal of Physical and Chemical Reference Data,1990,19(3):763-808.
计量
- 文章访问数: 3673
- HTML全文浏览量: 66
- PDF下载量: 4009
下载:
