Abstract:

To find out main controlling factors and applicable conditions of separated layer fracturing commingled producing for coalbed methane in Panzhuang, the geological and engineering factors of successful implementation was studied based on the sorting and analysis of the geological characteristics, reservoir fracturing hydraulic and drainage data by selecting production wells for more than five years as the research object. The results show that the key to success is to guarantee that the fracture spreads sufficiently within coal seams and is limited in height, in order to avoid the hydraulic connections between the coal seams and the roof and floor aquifers near the wells. The commingled producing will be successful by insisting on “continuously, slowly, stably” production policy when the original reservoir pressure, critical desorption pressure match or have a little different among the coal seams.

Key words: coalbed methane, separated layer fracturing, commingled producing, reservoir pressure, critical desorption pressure, gas production