Experimental study on settlement law of multi-particle compound temporary plugging material in rough fracture

Abstract

To study the migration and settlement law of temporary plugging particle in fractures, a set of fracture visualization device with controllable pumping rate was built. Based on the experimental device, the influence of the parameters such as pumping rate, particle size combination and adding sequence on the sedimentation and accumulation of temporary plugging particle was studied respectively. The experimental results show that the amount of particle deposition in the fracture is the largest when the pumping rate is 0.04 m3⋅min-1; Under different particle size combinations, 3 mm particles settle earlier than 1 mm particles and the volume of the accumulation is proportional to the proportion of 3 mm particles. The effect of the sequence of addition on the morphology of the particle accumulation is mainly reflected in the layering of the accumulation. When the 3 mm particles are added first and then the 1 mm particles are added, the accumulation volume is larger and the particles settle more. In summary, when a combination of 0.04 m3⋅min-1 rate and 3 mm: 1 mm=4:2 particle size is selected, and 3 mm is added first, and then 1 mm particles are added, the temporary plugging particle has a larger volume of sedimentation in the fracture.