一种固体颗粒酸酸化过程预测新模型及其应用

A New Prediction Model of Solid Particle Acidification Process and Its Application

固体颗粒酸作为一种缓速酸液体系,在碳酸盐岩储层酸化过程中具有能够沟通储层深部的优势。理清碳酸盐岩储层内固体颗粒酸的酸化机制,对于优选评价酸种类具有重要意义。为此,提出一种新的能够描述碳酸盐岩固体颗粒酸化过程的数学模型,能够刻画表征颗粒酸的缓释性能,进而研究不同注入速度及颗粒酸浓度等对碳酸盐岩储层酸化过程的影响机理。结果表明:入口周围区域颗粒酸浓度较低碳酸盐岩储层溶蚀较少,距离入口远端酸浓度存在高值分布。随着颗粒酸浓度的不断增大,溶蚀类型由均匀溶蚀转为特定方向的锥型蚓孔,且蚓孔长度不断增大而宽度不断降低;随着注入速度的增大,溶蚀类型由蚓孔转为均匀溶蚀,储层突破时间不断增大。

As a retarding acid solution system,solid particle acid has the ability to deeply enter carbonate reservoirs during acidification.It is of great significance for optimization and evaluation of acid types to clarify the acidification mechanism of solid particle acid in carbonate reservoirs.Thus,a new mathematical model for description of the solid particle acidification process of carbonate rocks was proposed to characterize the slow release performance of particle acid and further study the effects of injection rate and particle acid concentration on the acidification process of carbonate reservoirs.The results indicate that the carbonate reservoir is corroded less due to lower particle acid concentration around the inlet,and high acid concentration distributes far from the inlet.With increasing particle acid concentration,the type of corrosion changes from uniform corrosion to directional conical wormholes,and the length and width of the wormholes increase and decrease,respectively.With increasing injection rate,the type of corrosion changes from wormhole to uniform corrosion,and the breakthrough time of the reservoirs increases constantly.