Advancing Steamflood Performance Through a New Integrated Optimization Process: Transform the Concept into Practical
Authors: Silalahi Henri , Aji Muhamad , Elisa Afrilia , Perdayeni Arihta , Oktasari Rini , Lie Hendry , Akbarrizal Andri 
Published: October 2019

Duri Field is the largest active steamflood in the world comprising 6,300 active producing wells, 1,250 steamflood patterns and encompassing 21,000 acres in the Riau Province of Sumatra, Indonesia. The Duri Field produces 73,000 BOPD and 10,000 optimization jobs are executed annually to support base production. This asset is supported by teams that previously utilized tools and processes that are not necessarily consistent across areas to support reservoir management and production optimization efforts. The operator identified an opportunity to implement a new process to improve the quality of reservoir analyses, define short-term and long-term reservoir depletion strategies and the ability to develop a prioritized queue of executable production adding opportunities. The new process facilitates better cross functional engagement and enables a consistent application of best practices across the field. The process is a comprehensive review that incorporates a geological evaluation, a steamflood performance analysis, operational constraints, reservoir surveillance and an evaluation of the reservoir drainage efficiency.

The process employs use of digital technology for the purposes of mapping, modeling, analyzing downhole / surface surveillance data and evaluating production performance. A fieldwide geological evaluation is performed to analyze reservoir quality with relation to stratigraphy, structure and petrophysical properties. Reservoir surveillance data is analyzed to determine temperature, steamflood performance and depletion rates. Reservoir drainage efficiency is determined through a review of production (pattern and well), wellbore condition and reservoir surveillance data. Analytical tools were developed to improve the efficiency of the review process. The review process is effective at identifying areas with high remaining oil, stalled depletion and problematic steamfloods. Because of this effort, proactive workovers and production optimization opportunities are identified and prioritized based on economic potential and the ability to execute.

This new review process was implemented as a pilot in 2017 and fully implemented across Duri Field as a standard review process in 2018. Significant value has been created through this effort by: 1) developing a standardized and streamlined review process for all of Duri Field, 2) improving the ability for asset optimization teams to identify workover and optimization opportunities, 3) prioritizing job execution and 4) providing valuable insights to management to help make well informed investment decisions. In 2018, incremental production opportunities doubling the number of then-current production candidates were identified through this new process. The results of this effort have also provided valuable information for developing business planning.

This process demonstrates a successful evaluation and integration of static and dynamic reservoir properties, production data, operations and facility constraints. The automated and digital standard tools (e.g., geologic modelling, depletion tools, candidate selection, lookback tools, heating response tools) are introduced and proven to accelerate analyses and provide robust logic optimization evaluation.