多孔介质润湿反转为优先气湿及气体润湿性

INVERTED PREFERENTIAL GAS WET FROM LIQUID ONE AND ITS WETTABILITY IN POROUS MEDIA

理论和实验证实凝析气藏多孔介质表面润湿性由液湿转变为优先气湿可显著提高气井产量，且气湿程度对气井产量影响较大。但是目前，气体润湿性缺少定量评价方法，无法给出气湿性定量结论。通过理论分析和实验研究，分析了润湿反转的本质并实现了多孔介质表面由液湿性转变为优先气湿；然后提出了可表征固体表面气体润湿能力大小的参数ζ，应用停滴法建立了采用气湿参数ζ进行气湿性定量评价的方法，确立了气湿性定量评价指标，并采用毛细管上升实验，进一步验证了停滴法实验结果的正确性。实验结果表明：通过降低固体表面和固一液界面自由能是实现优先气湿的有效方法，随着Zonyl8740含量的增加，固体表面自由能降低，其表面的憎液亲气性增强。

The theoretical and test prove that the inverted surface wettability from liquid wet to preferential gas one for the porous media in condensate gas reservoirs can enhance the production of gas wells and moreover the degree of the gas wet possesses rather serious influence on the production. But at present, the gas wettability lacks of the quantitative evaluating method, thus the the quantitative evaluation cannot be drawn for the wettability. Through the theretical analysis and experimental study, the essence of the inversion is analyzed and furthermore the preferential gas wet can be realized; and then the parameter ζ is presented for characterized the ability of the gas wettability of the solid surface ; with the help of drop pausing method, the quantitative evaluating method for the gas wettability is established by adopting gas wettability parameter ζ, and moreover the quantitative evaluating index is determined for the wettability. Finally by means of capillary rise experiment, the accuracy of the tested results through the drop pausing method is further verified. The experimental results show that the preferential gas Wettability has been effec- tively realized by the method of reducing the surface free energy between the solid surface and the solid - liquid in- terface; with the rise of Zony18740~ concentration, the surface free energy of the solid surface is reduced and fur- thermore the the lyophobic gas wettability of the surface is increased.