Abstract

YANG, Yu et al. The pilot appraisal of acid fracturing of coalbed methane reservoir in southeast Qinshui Basin, China. Earth Sci. Res. J. [online]. 2016, vol.20, n.4, pp.C1-C6. ISSN 1794-6190.  https://doi.org/10.15446/esrj.v20n4.61633.

The reserves of Coalbed Methane (CBM) in Qinshui Basin are quite promising, but the outputs from CBM wells are quite small even after massive hydraulic fracturing. Herein the fracture system with #3 and #15 coal seams in Qinshui basin was analyzed, and it was found that both of the macro-scale fractures and micro-scale fractures are filled with clay and carbonate minerals, which explains the low productivity of CBM wells after conventional hydraulic fracturing. Acid fracturing has long been an effective method for carbonate gas reservoir to improve the gas well production. However, there were few reports about the application of acid fracturing in coal bed methane field. Based on the mineral identification and acid sensitivity test, the feasibility of acid fracturing demonstrated that the acid does more help than damage to increase the permeability of coal seams in Qinshui basin. Onsite operations have shown that acid fracturing is applicable for the CBM wells in Jincheng Mining Area. It was also observed from the microseismic survey that when applying the acid fracturing treatment, the stimulated reservoir area depends on the acid volume pumped in the first stage, which is crucial to the success of the stimulation.

Keywords : Coalbed Methane; Acid Fracturing; Acid Sensitivity Test; Stimulated Reservoir Area.

        · abstract in Spanish     · text in English     · English ( pdf )