The Calculation Method of Bottomhole Pressure during Shut-in Period in High Temperature and High Pressure Gas Well
-
摘要: 常规的井底压力预测方法认为,气井关井后压力恢复初期井口测压受到井筒储集效应影响,后期受温度降低引起的续流影响,并且在压力恢复期间井筒中不存在流体的流动。但是,新疆克拉2气田部分高温高压气井的实测结果表明,关井后测得的井口压力恢复曲线总体呈下降趋势,与常规方法所计算的压力曲线并不一致。对高温高压气井关井后的井筒温度特征、井筒续流特征和井筒流体参数变化特征进行了分析,认为,关井期间井口(底)压力同时受到井筒储集效应和温度变化的影响,并且在压力恢复过程中井筒内一直存在续流流动,需要进行流动气柱压力计算。为此,综合考虑井筒续流、井筒温度及井筒流体参数的变化特征,基于井筒压力恢复原理,建立了关井期间的井底压力计算模型,并对该模型进行了实例计算验证。实例验证表明,该模型计算出的压力恢复曲线正常,可用于产能试井解释。Abstract: In the conventional method of bottomhole pressure prediction it is assumed that the wellhead pressure is affected by the wellbore storage at the beginning of pressure buildup and by the afterflow in the late stage because of the temperature drop.And it is also assumed that there is no fluid flow in the wellbore after shut-in.However,according to testing results of some high pressure and high temperature wells in Kela-2 Gas Field,there was a pressure drop in the wellhead pressure build-up curve which is different from the conventional pressure build-up curve.The changing characteristics of wellbore temperature,the wellbore afterflow and the fluid parameters during the pressure build-up test then were analyzed.It is believed that the wellhead pressure or bottomhole pressure would be affected by both wellbore storage and wellbore temperature simultaneously.And there was afterflow in the wellbore during the whole test.So,the bottomhole pressure needs to be calculated by the flowing pressure equation.Based on the wellbore pressure build-up theory,the bottomhole pressure calculating model is established considering the effect of wellbore afterflow,the wellbore temperature changing and the fluid parameters changing.Taking one gas well for example,the pressure buildup curve calculated by this model is normal,and it can be applied for interpretation in the deliverability test.
-
Keywords:
- gas well /
- high temperature /
- high pressure /
- shut-in /
- wellhead pressure /
- bottomhole pressure
-
-
[1] 李士伦.天然气工程[M].北京:石油工业出版社,2008:85-134. Li Shilun.Natural gas engineering[M].Beijing:Petroleum Industry Press,2008:85-134. [2] 陈元千.气井垂直管流计算方法的推导与应用[J].断块油气田,2010,17(4):443-447. Chen Yuanqian.Derivation and application of calculating methods of vertical pipe flow in gas wells[J].Fault-Block Oil Gas Field,2010,17(4):443-447. [3] Anklam E G,Wiggins M L.A review of horizontal-wellbore pressure equations.SPE 94314,2005.
[4] 杨涛,杨桦.利用气井环空气柱压力计算井底压力新方法的研究与应用[J].天然气工业,2001,21(2):66-70. Yang Tao,Yang Hua.Research on a new method of calculating bottomhole pressure by the gas column pressure in annular space of gas well and its application[J].Natural Gas Industry,2001,21(2):66-70. [5] 唐海,李丽雄,曾凡华,等.气井油套合采时井底流压的计算方法[J].西南石油学院学报,2001,23(5):23-25. Tang Hai,Li Lixiong,Zeng Fanhua,et al.Method of wellbore pressure calculation for tubing-casing production system of gas wells[J].Journal of Southwest Petroleum Institute,2001,23(5):23-25. [6] 廖新维,沈平平.现代试井分析[M].北京:石油工业出版社,2002:206-217. Liao Xinwei,Shen Pingping.Modern well test [M].Beijing:Petroleum Industry Press,2002:206-217. [7] 冉新权,陈钦雷,赵必荣.气井井口压力恢复曲线异常的处理方法研究[J].天然气工业,1995,15(6):24-27. Ran Xinquan,Chen Qinlei,Zhao Birong.Treatment method reseach on wellhead pressure build up curve abnormality of gas well[J].Natural Gas Industry,1995,15(6):24-27. [8] Hasan A R,Kabir C S.Aspects of wellbore heat transfer during two-phase flow[J].SPE Production Facilities,1994,9(3):211-216.
[9] Hasan A R,Kabir C S,Lin D Q.Analytic wellbore-temperature model for transient gas-well testing[J].SPE Reservoir Evaluation Engineering,2005,8(3):240-247.
[10] 李相方,任美鹏,胥珍珍,等.高精度全压力全温度范围天然气偏差系数解析计算模型[J].石油钻采工艺,2010,32(6):57-62. Li Xiangfang,Ren Meipeng,Xu Zhenzhen,et al.A high-precision and whole pressure range analytical calculation model of natural gas Z-factor[J].Oil Drilling Production Technology,2010,32(6):57-62. [11] Nickens H V.A dynamic computer model of a kicking well.SPE 14183,1987.
[12] 尹邦堂,李相方,隋秀香,等.计算机优化压井开环控制软件系统研究及应用[J].石油钻探技术,2011, 39(1):110-114. Yin Bangtang,Li Xiangfang,Sui Xiuxiang,et al.Research and application of computer optimization open-loop well killing software system[J].Petroleum Drilling Techniques,2011,39(1):110-114.
计量
- 文章访问数: 3824
- HTML全文浏览量: 74
- PDF下载量: 3490
下载:
