Stress Sensitivity of Permeability Affected to Production Capacity of Coal Bed Methane Well

In order to get a production equation of a coal bed methane well and to analyze the sensitive parameters, based on the vadose law of the seam fluid,the production capacity equation with the permeability and stress sensitivity under the Darcy flow and non-Darcy flow were deduced and the inflow performances of the coal bed methane well in a seam of WL1 well was studied.The results showed that whether a Darcy flow or non-Darcy flow,after the stress sensitive,the production capacity of the coal bed methane well was obviously reduced. The no resistance flow would be reduced by 12. 4% in maximum.When stress sensitive cofficient of the the perme ability rate changed,the higher sensitive coefficient,the more the production capacity of the coal bed methane would be reduced. Once the production pressure differenc e was small,although the stress sensitivity influence was not obvious,the production value would be low.Once the production pressure difference was too high,the strata energy would be waste.Therefore,a rational production pressure difference set at the development period would be very important.