Acta Petrolei Sinica ›› 2020, Vol. 41 ›› Issue (10): 1266-1277.DOI: 10.7623/syxb202010011

• Petroleum Engineering • Previous Articles     Next Articles

Mechanism of gas well liquid loading and a new model for predicting critical gas velocity

Li Jinchao1,2, Deng Daoming1, Shen Weiwei1,3, Gao Zhenyu1,4, Gong Jing1   

  1. 1. MOE Key Laboratory of Petroleum Engineering/National Engineering Laboratory for Pipeline Safety, China University of Petroleum, Beijing 102249, China;
    2. Offshore Oil Engineering Co., Ltd., Tianjin 300461, China;
    3. Naval Logistics Academy, Tianjin 300450, China;
    4. PetroChina Oil&Gas Pipeline Control Center, Beijing 100007, China
  • Received:2019-10-29 Revised:2020-05-24 Online:2020-10-25 Published:2020-11-05

气井积液机理和临界气速预测新模型

李金潮1,2, 邓道明1, 沈伟伟1,3, 高振宇1,4, 宫敬1   

  1. 1. 中国石油大学(北京)石油工程教育部重点实验室/油气管道输送安全国家工程实验室 北京 102249;
    2. 海洋石油工程股份有限公司 天津 300461;
    3. 海军勤务学院 天津 300450;
    4. 中国石油北京油气调控中心 北京 100007
  • 通讯作者: 邓道明,男,1965年1月生,1984年获西南石油学院学士学位,2005年获中国石油大学(北京)博士学位,现为中国石油大学(北京)机械与储运工程学院副教授,主要从事石油多相流和油气集输、天然气地面工程、油气管道工程、油气储存的教学和科研工作。Email:ddmmpf@cup.edu.cn
  • 作者简介:李金潮,男,1992年12月生,2017年获辽宁石油化工大学油气储运工程专业学士学位,现为中国石油大学(北京)机械与储运工程学院硕士研究生,主要从事多相管流及油气田集输技术研究工作。Email:jinchao_lihuan@qq.com
  • 基金资助:

    国家科技重大专项(2016ZX05066-005-001,2016ZX05028-004-001)资助。

Abstract:

Wellbore liquid loading is one of the problems faced in the production process of gas wells. Liquid loading will cause the yield of gas wells to decrease, and even cause the off production of gas wells in severe cases. Accurately predicting the critical liquid-carrying gas flow rate of a gas well can help producers take timely measures to prevent the occurrence of liquid loading. Through comparing the minimum pressure gradient model, droplet model and liquid film model, and analyzing the results of the liquid loading experiment, it is indicated that the reverse movement of liquid film is the main reason for gas well liquid loading. According to the velocity profile of the liquid film in different ranges of gas velocity, this paper defines the gas superficial velocity corresponding to the zero shear stress between liquid film and pipe wall as the critical gas velocity of gas well liquid loading. Based on the annular mist flow pattern and taking into account the influence of such factors as pipe diameter, liquid flow rate and also droplet entrainment in the gas core, this study develops a zero shear stress model suitable for predicting the liquid loading of vertical gas wells. The new model and the existing prediction models of liquid loading are compared and verified by experimental data and field data; and the prediction accuracy and error of the model are used as evaluation indicators. The results show that the prediction agreement of the new model is better than other models, and the new model based on zero shear stress can predict the gas well liquid loading more accurately.

Key words: liquid loading, annular mist flow, liquid film, velocity profile, zero shear stress, critical gas velocity, vertical gas well

摘要:

井筒积液是气井生产过程中面临的问题之一,积液会导致气井产量降低,严重情况下甚至造成气井停产。准确预测气井临界携液气相流速可以及时采取措施以预防积液的发生。对比最小压力梯度模型、液滴模型和液膜模型并分析积液实验的结果表明,液膜反向是气井积液的主要原因。根据液膜在不同气速范围内速度分布规律,将液膜与管壁剪切应力为0对应的气速作为气井积液临界气速。基于环雾流型并考虑到管径、液相流速、气芯中液滴夹带等因素的影响,构建了适用于垂直气井积液预测的零剪切应力模型。利用实验数据和现场数据对新模型及已有的积液预测模型进行对比验证,以模型预测结果正确率和预测误差为评价指标。结果显示,新模型的预测效果优于其他模型,基于零剪切应力的新模型能够较准确地预测气井积液。

关键词: 积液, 环雾流, 液膜, 速度分布, 零剪切应力, 临界气体流速, 垂直气井

CLC Number: