Design Of Three-phase Centrifuge Using For Treatment Of Oily Drill Cuttings

In shale gas drilling,there exists such environmental pollution of oil based cuttings and waste water caused by using oil based drilling fluid,so three-phase centrifuge is developed.Considering the oil-based drilling cuttings cleaning technology and waste liquid demulsification separation,a three-phase centrifuge suitable for oil based drilling cuttings and waste liquid treatment is developed to meet the needs of environmental protection treatment in shale gas drilling.This project adopts finite element method and hydrodynamics method to analyze the strength of centrifuge drum and the flow field morphology of centrifuge inlet structure,and optimizes the structure scheme of centrifuge.According to the characteristics of oil based drilling cuttings and waste liquid,a real-time regulation mechanism of centrifuge overflow,a centrifuge level adjustment device and a low differential screw thruster are designed to improve the performance of centrifuges.The centrifuge hydraulic differential and hydraulic system are designed to improve the pushing torque of centrifuge screw propeller and avoid drum blockage caused by high solid content in drilling cuttings.Using variable frequency speed regulation technology,the main parameters of three phase centrifuge are achieved: stepless speed regulation of rotary drum,differential speed and liquid inlet volume.It is easy to operate,and it is convenient to transport and install.The three phase centrifuge has been tested on the site of 2HF well in Yong ye.The performance of the three-phase centrifuge is stable,and oil,water and solid of three phase separation are realized after the tempering oil based drilling chips are treated by three phase centrifuge.The field test results show that the performance of the three-phase centrifuge can meet the design requirements.