西南石油大学学报(自然科学版)

• 石油与天然气工程 • 上一篇    下一篇

低渗气藏水平井二项式产能方程修正

杨程博1,2,郭建春1,杨建3,徐守成3,袁彩霞4   

  1. 1.“油气藏地质及开发工程”国家重点实验室 西南石油大学,四川成都610500;2. 中国石化新星石油有限责任公司,北京海淀100083
    3. 中国石化西南油气分公司勘探开发研究院,四川成都610081;4. 北京邮电大学计算机学院,北京海淀100876
  • 出版日期:2014-08-01 发布日期:2014-08-01
  • 基金资助:

    国家重大专项“大型油气田及煤层气开发”子课题“低渗透气藏复杂结构井地质优化设计研究”(2011ZX05022–001–002)。

Modification of Horizontal Well Binomial Deliverability Equation of Low Permeability Gas Reservoir

Yang Chengbo1,2, Guo Jianchun1, Yang Jian3, Xu Shoucheng3, Yuan Caixia4   

  1. 1. State Key Laboratory of Oil and Gas Reservoir and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China
    2. Star Petroleum Co. Ltd.,SINOPEC,Haidian,Beijing 100083,China
    3. Exploration & Production Institute of Southwest Petroleum Branch Company,SINOPEC,Chengdu,Sichuan 610081,China
    4. School of Computer Science,Beijing University of Posts and Telecommunications,Haidian,Beijing 100876,China
  • Online:2014-08-01 Published:2014-08-01

摘要:

低渗气藏普遍存在启动压力梯度和应力敏感现象,而目前低渗气藏水平井二项式产能方程却未完全考虑这两个因素的影响,导致计算出的无阻流量出现较大偏差,单井合理产能认识不准。从低渗气藏渗流理论出发,在 Forchheimer 渗流方程中引入启动压力梯度和应力敏感系数,推导了含启动压力梯度和应力敏感的低渗气藏水平井产能修正方程。以川西某气藏岩芯实验数据和某水平井试井资料为基础,在考虑启动压力梯度时,采用修正方程计算出的无阻流量较常规二项式产能方程降低了9.44%;而在考虑应力敏感时,其无阻流量降低了35.08%;同时考虑两个因素影响时,无阻流量更是降低了43.41%;计算结果表明,运用修正后的方程计算的无阻流量与常规方法计算结果存在一定的差异性,建议使用修正的方法进行无阻流量计算与产能预测。

关键词: 低渗气藏, 拟稳定渗流, 应力敏感, 启动压力梯度, 水平井, 二项式产能方程

Abstract:

The phenomena of start-up pressure gradient and stress sensitivity are quite prevalent in low permeability gas reservoir. However,at present,the effects of the two factors are not yet fully taken into consideration in the binomial expression deliverability equation of the horizontal well. In this paper,based on the filtration theory of the low permeability gas reservoir, start-up pressure gradient and stress sensitivity are introduced into the Forchheimer flow equation,which ultimately arrives at the modified horizontal well deliverability equation after strict deduction. Based on the data of core experiment and certain horizontal well test data of a gas reservoir located in the west of Sichuan,when the startup-gradient of pressure is taken into account,the open flow potential calculated through the modified binomial expression deliverability equation is 9.44% lower than that obtained from conventional binomial expression deliverability equation;when stress sensitivity is taken into account, the open flow potential reduces by 35.08%;when considering both two factors,the open flow potential reduces by 43.41%. The calculation results show that there exist certain differences between the modified equation and conventional methods in calculating the open-flow potential. And we recommend modified equation in the open-flow potential calculation and productivity prediction.

Key words: low permeability gas reservoir, pseudo steady state fluid, stress sensitivity, starting pressure gradient, horizontal
well,
binomial deliverability equation