Numerical Simulation Of Loop Reactor And Sparger For Slurry Bed Hydrocracking

The world crude oil is becoming heavier and poorer in quality and the demand of clean fuels is becoming larger.The hydrocracking process is an important process to convert the heavy oil to light fraction,so it plays an important role in oil processing industry in china.The development and optimization of loop reactor and sparger has been the keystone and difficulty to optimize hydrogenation process.A computational fluid dynamics,CFD,with Eulerian-Eulerian double-phase model and standard k–? turbulence model was developed to predict the complex two-phase flow,the three-dimensional full size of the loop reactor and the sparger was then simulated.In this paper,five different types of sparger have been discussed and compared: single nozzle,multiple nozzle,venturi nozzle,ring sparger and spider sparger.As for ring sparger and spider sparger,the factor such as head diameter,ring diameter,hole pitch,hole diameter and pipe(ring)numbers was discussed in detail.These two types of the sparger were also simulated separately without the reactor to investigate the distribution of the hole velocity.Then the optimized pipe sparger and the nozzle sparger were placed in the bottom of the loop reactor to simulate the whole flow field.The factors to be considered are gas holdup and oil velocity.The flow situation at the bottom of the reactor was also discussed.Finally,the optimal position of the sparger was discussed at the end of the paper.The design procedure of pipe sparger was discussed in detail in this paper.The performance of nozzle sparger and pipe sparger in loop reactor was studied,the position of sparger was also optimized in this paper.The simulation results have confirmed the applicability of the model.It has great significance for the slurry bed hydrocracking process and can provide a basis for the slurry bed hydrocracking process industrialization.