某加氢加热炉炉管安全性分析与寿命预测
-II-
Safety Analysis and Life Prediction of a Hydrogenation Furnace Tube
Abstract
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 150wt / 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, TP347H 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 TP347H material is obtained by using
Matlab fitting curve function, and the service life of the heating furnace tube is evaluated
accurately.
