过氧化氢对气煤大分子结构及润湿性的影响OA

[Purposes]Oxidative modification of coal reservoirs by hydrogen peroxide to in-crease permeability is one of the potential advanced technologies for production increase in the field of coalbed methane(CBM).However,the microscopic mechanism of surface modification of coal by hy-drogen peroxide and its side effects are still unclear.[Methods]In order to find out the effect of oxi-dizing agent treatment on the macromolecular structure and wettability of coal surface,15%H2O2 was used to act on the gas coal in Baode mine area.According to proximate and ultiamte analyses,Fourier transform infrared spectroscopy,solid state nuclear magnetic resonance carbon spectroscopy,X-ray photoelectron spectroscopy and wettability test,the macromolecular structure models of raw and oxi-dized gas coals were established to analyze the response relationship between hydrogen peroxide and coal macromolecular chemical structure modification,and the influence of wettability change of coal af-ter oxidizing modification on CBM development was discussed.[Results]The results indicate that H2O2 reacts with both of aromatic and fatty parts of Baode coal,but the reaction with the fatty part is more intense,resulting in a decrease in the proportion of the oxidized coal sample's fatty part and an increase in the proportion of the aromatic part.At the same time,after the action of H2O2,low concen-tration aromatic nuclei break,leading to longer fatty chains,while high concentration aromatic nuclei have stable structures and are not easily oxidized,so the degree of condensation of aromatic structures increases after oxidation.Finally,oxidation increases the content of polar functional groups,resulting in enhanced hydrophilicity and weakened aerophilicity of coal surface,which is conducive to CBM de-sorption.However,it also leads to the increase of bound water saturation and the decrease of gas phase permeability,which is not conducive to the drainage and seepage of CBM wells.[Conclu-sions]The research results have theoretical guiding significance for the optimization of coal reservoir oxidation modification infiltration technology.