压裂支撑剂在水平井井筒射孔簇间分布实验

Experimental on Distribution of Fracturing Proppant between Perforating Clusters in Horizontal Wellbore

为研究支撑剂在射孔簇中的分布,分析支撑剂沿水平井筒沉降的原理,建立了室内实验模拟装置,通过改变支撑剂泵注排量、粒径、砂比等参数,分析上述因素对支撑剂在射孔簇中分布的影响。研究结果表明:在低泵注排量下,随着砂比的增大,20/40目石英砂主要分布由第2、3个射孔簇变为第1、2个射孔簇,40/70目石英砂主要集中在第1个射孔簇中;高泵注排量下,20/40目石英砂分布与低泵注排量类似,40/70目石英砂受高速流体影响,以远超临界沉积速度的形式运移,大量沉积在第3个射孔簇;相同砂比情况下,流体对小粒径石英砂的冲击作用较弱,支撑剂易沉积在近处,而对大粒径石英砂的冲击作用较强,更易沉积在远处;随着砂比的增大,支撑剂在第1个射孔簇中的质量占比逐渐增大,在第3个射孔簇中的质量占比显著减小。该研究可为水平井分段压裂射孔簇优化和提高改造效果提供有力支撑。

In order to study the distribution of proppant in the perforation cluster and analyze the principle of proppant settlement along the horizontal wellbore,an indoor experimental simulation device was established to analyze the influence of the factors above on the distribution of proppant in the perforation cluster by changing the parameters of proppant pumping displacement,particle size,sand ratio,etc.The results of the study show that under the low pumping displacement,with the increase of sand ratio,the distribution of 20/40-mesh quartz sand mainly changed from the 2ndand 3rd perforation clusters to the 1st and 2nd perforation clusters,and 40/70-mesh quartz sand mainly concentrated in the 1st perforation cluster;under the high pumping displacement,the distribution of 20/40-mesh quartz sand was similar to the low pumping displacement,and 40/70-mesh quartz sand was influenced by the high speed fluid and migrated at a speed far beyond the critical deposition rate,and mainly deposited at the 3rd perforation cluster.Under the same sand ratio,the impact of fluid on small-sized quartz sand is weaker,so the proppant was easily deposited nearby,while the impact on large-sized quartz sand is stronger and more easily deposited far away;with the increase of sand ratio,the mass proportion of proppant in the 1st perforation cluster gradually increases,and significantly decreased in the 3rd perforation cluster.This study provides a strong support for the optimization of perforation clusters for horizontal well staged fracturing and improvement of the stimulation effect.