Analysis of influencing factors on productivity of coalbed methaneof combined multi-layer drainage wells

In order to study the main controlling factors and inter-layer interference law of coalbed methane drainage well production capacity, this paper took the physical parameters of the upper coal seam group in an inclined coalbed methane exploration and development test area of Guizhou Huangnitang as the data source, and established a multi-factor and multi-level two-layer mining geological model with COMET3 numerical simulation software. In this paper, the orthogonal experiment was used to design the thirteen-factor three-level orthogonal table and the difference analysis method. The simulation results showed the main controlling factors of the combined layer drainage, which can be listed according to its influence from high to low as: preservation ratio, reservoir permeability, gas content, porosity, layer spacing, methane adsorption time, and layer thickness.Four factors of preservation ration, reservoir permeability, gas content and layer thickness were simulated respectively.The results showed that the inter-layer interference did not exist under the same pressure coefficient, and the main controlling factors of the combined multi-layer drainage and production were the temporary storage ratio and reservoir permeability.