Production feature and influencing factors of deep coalbed methane In Linxing Block

The production characteristics of deep coalbed methane are significantly different from those of medium and shallow coalbed methane, and there are also differences in the drainage wells within the same block.Due to the fact that relevant research is still in the exploratory stage, the analysis of factors affecting the production characteristics of deep coalbed methane is of great significance for the production capacity research and production management in the subsequent large-scale development stage of this field.Deep coalbed methane wells in the Linxing block can be divided into three types based on production characteristics： self flowing wells in supersaturated gas reservoirs, drainage wells in supersaturated gas reservoirs, and drainage wells in undersaturated gas reservoirs.To clarify the influencing factors of deep coalbed methane production characteristics in the Linxing block, this article conducts research based on geological engineering factors such as gas content, coal thickness, burial depth, hydrochemical characteristics, and fracturing technology.The results show that： (1) Gas content is the main controlling factor for the three production characteristics, and the gas content and stable production of coalbed methane wells buried at depths of 1 800-2 000 meters in the work area are relatively high; (2) The storage conditions of undersaturated gas reservoir drainage wells are poor, and there are significant differences in hydrochemical characteristics compared to the other two types of wells, resulting in relatively poor production efficiency.Moreover, due to high salinity and high bicarbonate ions, the scaling and corrosion of the pipe columns can cause discontinuous drainage; (3) Large scale fracturing is an effective reservoir transformation measure to increase gas well production, and the effective support of fracturing sand on fractures is a key factor in ensuring high gas production and stable production in deep coal seam wells.The above achievements have clarified the influencing factors of the differences in the production characteristics of deep coalbed methane in the Linxing block, and have guiding significance for the production of deep coalbed methane in the research area and adjacent areas.