Two experimental wells were selected on site, and the direct reading downhole permanent pressure gauge was put in. The data was directly transmitted to the headquarters database through PetroChina remote transmission system.

Each well is divided into six stages, four times in single-phase water phase and two times in gas production stage.

after more than 10 months of field test, the test data are obtained, and the self-developed coalbed methane analysis and numerical simulation software is used for analysis and calculation.

This project has carried out a lot of research on CBM drainage and production, carried out the analysis and interpretation of CBM dynamic data, and achieved the following test results:

To verify the influence degree of post pressure drainage mode on gas well seepage capacity.

The situation of gas saturation of different gas release pressure fractures compares to casing pressure.

To verify the change of seepage capacity of gas well water in the process of stable casing pressure gas release reaching production capacity.

Compare the formation pressure recovery of the same well before and after casing pressure.

To verify the layered water production capacity of drainage process before layered combined production and desorption.

Put forward a new concept of pressure-drainage-production whole process analysis for optimization of CBM drainage system.