Permeability inversion and main control factors of hydraulic fracturing transformation of surface coalbed methane wells
LI Geng
CHEN Benliang
LIANG Xing
DING Hai
LI Yanqing
FANG Huijing
FENG Anxiang
WANG Bo
XIE Zhizai
CAO Tengfei
ZHOU Tao
Abstract：Reservoir reform is one of the key technologies for CBM development.The permeability in-version is a key parameter for evaluating the effect of reservoir reform.Based on the drainage data of 10 development wells in the research area,the well test method was used to invert the reservoir per-meability after fracturing transformation,the type of fracturing curve was divided,and the reservoir reformation effect was qualitatively evaluated,the influence of geological factors and engineering fac-tors on the transformation effect is analyzed.The permeability of the reservoir development in the study area is between 0.38 and 64.10 mD,and the variation of the permeability before and after the transformation is between 4 and 293 times.The research shows that the higher in-situ permeability and higher proportion of primary fractured coal are beneficial to the reservoir reconstruction effect,and the modified permeability increases with the increase;the larger buried depth and higher ground stress condition is not conducive to the reservoir transformation,and the transformation permeability decreases with the increase;the larger fracturing fluid strength,the sand-carrying fluid strength,the sand-adding strength,and the sand-carrying liquid displacement are beneficial to the transformation of the reservoir permeability.The higher sand ratio is not conducive to the reservoir transformation,and the modified permeability decreases with the increase of its value;the combination of cracking does not enhance the permeability of the transformation,the reservoir transformation permeability it de-creases as the number of fracturing layers increases.When carrying out multi-coal reservoir recon-struction,it is preferred to have a shallower buried depth,lower in-situ stress and larger in-situ per-meability,and the primary fractured coal dominates the coal seam,and appropriately increase the fracturing fluid,sand-carrying fluid,Adding sand strength,reducing sand ratio,and performing single coal lamination cracking.
Keywords：permeabilitytransformation effectmain control factorhydraulic fracturingcoalbed met-hane
Publication Date：2025-04-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 73-81 )