Water Cut Changing Rules After Liquid Rate Increasing in Strongly Heterogeneous Reservoirs

Abstract

Commonly, the strong heterogeneity leads to poorer sweep efficiency for poor reservoir. So, liquid production rate optimization was often used to improve development effect, especially liquid production rate increasing in high water cut stage. However, the quantitative relationship between the rising law of water cut and the main control factors is not clear, which results in the uncertainty of water cut changing after liquid increasing. This paper proposed a theoretical prediction model of water cut presenting the correlations between water cut and formation parameters, fluid property parameters, relative permeability parameters and production control conditions. Furthermore, the water cut rising law is theoretically divided into three types (continuous rising type, stable type and step type). Moreover, the theoretical equation of water cut change after liquid increasing is established, and the critical mathematical conditions were clarified for different kinds of water cut changing law such as water cut rising, unchanged or decreasing in complex multi-layer reservoirs. Then, oil rate increment and liquid rate changing can be predicted quantitatively further. The proposed method could be used for the working system optimization, stimulation optimization and development plan adjustment. It has been proved to have a high accuracy based on the actual dynamic data.

Copyright 2018, Shaanxi Petroleum Society.

This paper was prepared for presentation at the 2018 International Field Exploration and Development Conference in Xi’an, China, 18–20 September, 2018.

This paper was selected for presentation by the IFEDC Committee following review of information contained in an abstract submitted by the author(s). Contents of the paper, as presented, have not been reviewed by the IFEDC Committee and are subject to correction by the author(s). The material does not necessarily reflect any position of the IFEDC Committee, its members. Papers presented at the Conference are subject to publication review by Professional Committee of Petroleum Engineering of Shaanxi Petroleum Society. Electronic reproduction, distribution, or storage of any part of this paper for commercial purposes without the written consent of Shaanxi Petroleum Society is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract must contain conspicuous acknowledgment of IFEDC. Contact email: paper@ifedc.org.