Study on Well Spacing Optimization in a Tight Sandstone Gas Reservoir Based on Dynamic Analysis

Area of Science:

• Petroleum Engineering
• Unconventional Resources
• Reservoir Management

Background:

• Tight gas is a priority unconventional resource in China, distinct from shale gas and coalbed methane.
• Enhancing gas recovery in tight gas fields is crucial, influenced by geology, drainage area, and well spacing.
• Effective drainage area estimation and well spacing optimization are vital for tight gas exploitation.

Purpose of the Study:

• To establish a novel optimization workflow for tight gas field development.
• To combine dynamic analysis and numerical simulation for improved gas recovery.
• To provide guidance for optimizing well spacing and drainage area in tight gas fields.

Main Methods:

• Utilized interference well test results and production data for dynamic analysis.
• Developed a numerical model to determine optimal well spacing.
• Integrated economic evaluation for well density optimization.

Main Results:

• The workflow successfully estimated single well drainage area and determined optimal well patterns.
• Applied to the Sulige gas field, the approach yielded a most reasonable well pattern of 500 m × 600 m.
• The combined methods allow for prediction of total gas production and optimization of well density.

Conclusions:

• The proposed workflow effectively guides tight gas field operators with available well test and production data.
• Optimized well spacing significantly impacts gas recovery in tight sandstone reservoirs.
• The 500 m × 600 m well pattern is identified as optimal for the Sulige pilot gas field.