压裂火山岩气井多裂缝产能模型

THE MULTIPLE FRACTURES PRODUCTIVITY MODEL FOR FRACTURING VOLCANIC ROCKS GAS WELLS

目前,我国发现的火山岩气藏主要位于松辽盆地,该地区火山岩气藏的储层普遍为低孔低渗储层,自然产能非常低,普遍需要进行压裂改造才能获得工业气流。由于火山岩气藏普遍发育微裂缝,因此受微裂缝的影响,在压裂的过程中常常形成与常规压裂不同的多裂缝,给生产动态准确预测带来了非常大的困难。基于气体单相稳定渗流规律,运用保角变换和等值渗流阻力原理,考虑压裂多裂缝的影响,建立了压裂火山岩气藏多裂缝产能方程。根据实例分析表明,压裂火山岩气藏多裂缝产能模型计算结果同生产实际相符,可以真实地反映压裂火山岩气井的生产能力,能够准确地预测压裂火山岩气藏气井流入动态。

At present, the volcanic gas reservoirs discovered in China are mainly located in the Songliao basin, where the volcanic gas reservoirs, commonly with the characteristics of low permeability and poor natural productivity, generally need for fracturing treatment to obtain the industrial gas flow. As volcanic gas reservoirs usually develop the phenomenon of micro-cracks, the multiple fractures are usually formed differently from conventional fracturing in the process of fracturing due to the influence of micro-cracks, which pose great difficulties to the accurate prediction of production performance. Based on the stable seepage law for single-phase gas, by using the principle of conformal transformation and equivalent flow resistance and considering the impact of multiple fractures, the multiple fractures productivity equation for fracturing volcanic rocks gas wells has been established. According to case analysis, it is shown that the result calculated by the multiple fractures productivity model for fracturing volcanic rocks gas wells is consistent with actual production, which can truly reflect the real production capacity of fracturing volcanic rocks gas wells and accurately predict the inflow performance of gas wells in fracturing volcanic rocks gas reservoir.