Petroleum Reservoir Evaluation and Development ›› 2025, Vol. 15 ›› Issue (1): 110-115.doi: 10.13809/j.cnki.cn32-1825/te.2025.01.014

• Oil and Gas Development • Previous Articles     Next Articles

Study on variation in decline rate with water cut using relative permeability curves

MA Peishen1(), SUN Yili1, SHU Zheng2, TAN Yeqiang1, YU Qiang3, ZHANG Wei1, WU Changhu1, QI Yong2()   

  1. 1. Research Institute of Exploration and Development, Sinopec Henan Oilfield Compary, Nanyang, Henan 474780, China
    2. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, China
    3. No.1 Oil Production Plant, Sinopec Henan Oilfield Compary, Nanyang, Henan 474780, China
  • Received:2024-04-11 Online:2025-01-26 Published:2025-02-26
  • Contact: QI Yong E-mail:mapeishen@sina.com;2062478871@qq.com

Abstract:

To investigate the variation of production decline rate at different water cut stages during oilfield development, this study explored the relationship between decline rate, water cut rise rate, and water cut based on relative permeability curves. The relationship between decline rate and water cut under injection-production balance conditions was established, followed by computational analyses on a thick oil reservoir Z and a multi-layer oil reservoir S. The results showed that, under ideal injection-production balance conditions, the decline rate at a certain water cut stage was jointly influenced by liquid production rate and irreducible water saturation. The decline rate exhibited a parabolic trend with increasing water cut and was proportional to the liquid production rate. For a given reservoir under known conditions, the magnitude of the production decline rate was primarily determined by the liquid production rate and could be controlled by adjusting parameters such as well spacing density and the ratio of injection to production wells, which affected the liquid production rate. By establishing the relationship between decline rate and water cut, factors influencing production decline are clarified, providing a basis for strategies to mitigate production decline.

Key words: decline rate, relative permeability curve, water cut, water cut rise rate, liquid production rate

CLC Number: 

  • TE34