Abstract: The C₈ aromatics isomerization is an important reaction process for the production of p-xylene. This process is typically carried out in a radial bed reactor, with the scallop which is a key internal component of the radial bed reactor, playing a significant role in achieving uniform fluid distribution. A combination method of cold model experiments and computational fluid dynamics (CFD) simulation was used to analyze the pressure drop and flow field distribution inside the scallop. By comparing the experimental data with the simulation data,it was found that the relative error between the pressure drop inside the scallop and the average outlet velocity of the side holes under different gas velocities was less than 15%, which validated the accuracy of the established scallop simulation model. The influence of inlet gas velocity on the fluid flow characteristics inside the scallop was investigated, and it was found that the fluid distribution patterns were essentially consistent under different gas velocities. The gas velocity in the perforated section of the scallop is symmetrical along the circumference, with the gas velocity in the middle hole slightly lower than that in the two side holes. Due to the presence of the jet zone, the static pressure inside the scallop shows a trend of decreasing first and then increasing along the axial direction from top to bottom.

Key words: C₈ aromatics isomerization, scallop, radial bed reactor, computational fluid dynamics