Patent ID: 8469099

Claim:
A method of fracturing a subsurface coal formation penetrated by a well, comprising: treating the well and the subsurface coal formation with an acid to dissolve precipitates, contaminants, completion fluids, or cement which may be present at or adjacent the well; pumping a fracturing fluid containing propping agents into the subsurface coal formation adjacent the well in a multiplicity of stages and at a pressure sufficient to initiate the propagation of at least one fracture within the coal formation; pumping additional acid into the well and the at least one fracture to dissolve acid-soluble materials; alternatingly pumping an oxidizing agent solution into the subsurface coal formation following each of the multiplicity of stages, whereby the oxidizing agent solution etches channels into fracture faces; and overflushing the subsurface coal formation with a fluid configured to transport accumulated coal fines deeper into the subsurface coal formation for improved methane extraction.