Duijiangnan coal field in Guizhou province holds lots of coal beds with high content of methane, meaning abundant CBM resources, but high outbreak risk of CBM. This paper uses the volume method to estimate the CBM resources of minable coal beds, based on the prior extraction test. Extraction project is designed, and feasibility study is conducted by means of depreciated cash flow. Duijiangnan coal field is a medium sized CBM field with a resources potential of 31.05×10^8 m^3 and resources concentration of 1.56×10^8 m^3/km^2. Single well gains high production, up to 1 803.94 m^3/d, and comprehensive extraction rate is 31.26%-32.54% with a mining life of ten years. CMB content of the major coal bed M78 may decrease to 8.0-13.5 m^3/t, with economic extraction. This development project has good economic indexes with intern return rate of 8.22% after tax, a bit over the basic return rate. Net present value after tax is 914.2 thousand Yuan, with a payback period of 6.98 years, less than the basic payback period. It is proved to be a feasible project.

To study the feasibility of developing coalbed methane in coal mine and give guideline to application of this technology in coalbed methane development and gas control in coal mine, this paper evaluates the coalbed methane resource of Guanzhai coal mine based on its geology. Guanzhai coal mine has favorable geology and reservoir for coalbed methane with abundance of coalbed methane. Reservoir simulation software was used to forecast the single well gas production with result showing a higher rate, up to 932.00 m3/d in continuous 15 years. Gas from No.4 and No.9 coalbed decreased by 33.93% and 33.33%. Guanzhai coal mine has potential of large scale production of coalbed methane, and relatively safe. This feasibility study, combining geology and resource potential with production forecast, is effective in simulating coalbed methane in coal mine.