Safety Analysis And Life Prediction Of A Hydrogenation Furnace Tube

The catalyst can be suspended in the residue medium to participate in the catalytic cracking reaction.It has the characteristics of high conversion,low coking rate and high quality oil generation.At present,this technology has been applied in petrochemical industry and will be used in heavy oil catalytic cracking project.This is of great significance to alleviate the current situation of China's oil shortage and heavy dependence on imports.This paper aims to optimize the design,heat exchange,strength analysis and service life evaluation of the reaction medium(residue)heating furnace of the project.Firstly,according to the discharge capacity of 150 wt / year,the tube side structure and diameter of the furnace tube are designed.NX10.0 is used to build the 3D model of convection and radiation pipe segment.Secondly,workbench fluent is used to analyze the velocity field,pressure field and outlet temperature distribution of the residual oil in the tube,and observe whether the reaction temperature demand of the outlet medium is satisfied.By observing the velocity vector distribution of the fluid,it can be found that the velocity of the fluid at the elbow of the furnace tube is faster.Then,TP347 H is selected as the furnace tube material according to the actual working environment of high temperature and high pressure.The temperature distribution of the furnace tube is obtained after the temperature load is applied,and the high temperature concentration area is found as the dangerous area where the material may creep.Then,the temperature field and pressure field of the fluid structure coupling surface are added to the static structure analysis module as load,and the stress field of the furnace tube is obtained and compared with the theoretical stress value.Finally,the safety assessment of the maximum stress position is carried out by using the fracture mechanics strength theory.It is found that the maximum stress value is lower than three times of the allowable stress of the furnace tube material,and the design meets the strength requirements.According to high temperature strength and high temperature creep test,the life value of furnace tube material under certain temperature and different stress conditions is inferred.The L-M creep life equation of TP347 H material is obtained by using Matlab fitting curve function,and the service life of the heating furnace tube is evaluated accurately.