Experimental Research On The Separation And Recycling Efficiency Of Particles In Particle Impact Drilling System

Particle Impact Drilling (PID) technology is one new oil-drilling technology which has been developing in the near decade. It is widely concerned by oil workers for its long lifetime, high drilling speed and short working cycle, etc. The particle separation and recycling system is an important part in the whole drilling procession. Steel particles would encounter part of lose in separation and recycling processes. In order to keep the total amount of particles, the loss disciplines should be studied extensively. Based on experiments, this paper gets the factors governing the separation and recycling process, such as viscosity, flow, and ratio of particles etc., and the rules between steel particle lose rate and these physical parameters. What's more, mathematical model is built to analysis the relationship between steel particle lose rate and some physical parameters employing dimension analysis method.This paper focused on the vibrating screening process and magnetic separation process respectively through experimental research. For the first process, drilling fluid mixed with steel particles and rock debris particles go through the vibrating screen. Corresponding parameters including viscosity, flow velocity, density of drilling fluid, mass ratio of steel particles and rock debris particles, etc., are measured through experiments,. Dimension theory was employed to get the specific dimensionless equations between steel particles loss rate and physical parameters. Experimental results show that main factors affecting steel particle loss rate are viscosity and flow velocity of drilling fluid, and mass ratio between steel particles and rock debris particles, and whose increase lead to large lose rate.For the magnetic separation process, the mixture consisted with steel particles and rock debris particles go through the magnetic separator, and the steel particles and debris particles are separated as the difference in magnetic property. Parameters including rotate speed, diameter and size of magnetic roller, magnetic flux density of magnetic field, mass ratio of steel particles and rock debris particles, add speeds of steel particles and rock debris particles are recorded in experiments, as well as the steel particle lose rate. Dimension theory was employed to get the specific dimension equation that reflects steel particle loss rules. Experimental results show that main factors affecting the steel particle loss rate are mass ratio between steel particles and rock debris particles, whose increase would lead to high lose rate.Combining equations of steel particles in vibrating screen separation part and magnetic separation part, the lose rate equation of steel particles of whole separation and recycling system could be got. The problem discussed in the thesis is firstly studied national wild. Corresponding results could be helpful to govern the supplement speed of steel particles in PID system.