Abstract:

Based on coal geological exploration data, CBM testing drilling data and production data, W01 well of Panzhuang Block in southern Qinshui Basin was taken as the research object, the actual production data of 3# and 15# coal was fitted by Comet3 numerical simulation software to get some important reservoir parameters like reservoir permeability and gas content. Interference Coefficient was introduced to this paper and its sensitivity to reservoir parameters was discussed by controlling single variable method. According to the simulate of CBM production and reservoir pressure under the condition of single layer exploitation and commingled exploitation, the formation mechanism of interlamination interference during exploration was discussed. The results show that there is a big difference in coal reservoir pressure variation and delivery between single layer exploitation and commingled exploitation. Moreover, every coal seam has its unique reservoir character. All of these cause the great diversity in coal seam proportion within critical desorption pressure and CBM desorption ability and further make Interllamination interference. With the gas exploration, the Interllamination interference extent will decrease first and then increase and then decrease again. What affect Interllamination interference most are Permeability, porosity and Langmuir volume of coal while original reservoir pressure affects less.

Key words: CBM, Interlamination interference, Numerical simulation, Formation mechanism, Controlling factors