砾石充填防砂井砾石层堵塞机理实验研究

EXPERIMENTAL STUDY ON PORE-BLOCKING MECHANISM IN GRAVEL PACKS OF SAND CONTROL WELL

用不同粒度中值的砾石和地层砂对砾石层的挡砂机理进行了实验研究。结果表明 ,砾石充填防砂效果与砾石尺寸的选择密切相关 ,砾石层渗透率的降低与砾石及地层砂的粒径比、流体粘度、累积产液量等因素有关。对 5种粒度中值比的砾石与地层砂的挡砂结果进行了分析 ,根据其挡砂机理的不同 ,砾石挡砂类型可分为无地层砂侵入型、浅层内部桥塞型、孔隙堵塞与孔隙内部桥塞混合型、砾石层孔隙充填型和地层砂自由通过型。

An experiment on pore blocking mechanism in gravel pack was simulated with different gravels and different sands in diameters. The experimental results show that the size of gravel is an important factor for gravel pack sand control. The decline of gravel pack permeability is related to gravel sand radius ratio, production time and the viscosity of fluid. The pore blocking results of five gravels and sands with diffent gravel fine size ratio are analyzed. According to the difference of pore blocking mechanisms, they are devided into five kinds of no invasion, shallow internal bridging, combined internal bridging and pore blocking, proe filling, no interaction.