PetroChina Company Limited
Exploitation method and exploitation well pattern for coalbed methane in low-permeability coalbed

Abstract:

An exploitation method and an exploitation well pattern for coalbed methane in a low-permeability coalbed. The method comprises: determining a maximum principal stress direction in a low-permeability coalbed; disposing at least two large-roadway horizontal wells in the low-permeability coalbed; disposing a plurality of production wells on two sides of a horizontal segment of each of the at least two large-roadway horizontal wells, wherein a diameter of each of the production wells is smaller than a diameter of the horizontal segment; exploiting the coalbed methane in the low-permeability coalbed through the at least two large-roadway horizontal wells and the plurality of production wells. Through the horizontal segments of the large-roadway horizontal wells perpendicular to the maximum principal stress direction, it promotes stress release in low-permeability coalbed to form more fracture channels, thereby improving the exploitation efficiency of the coalbed methane in the low-permeability coalbed.