Abstract: With the deacidification process of distillate oil from the Shengli Refinery under SINOPEC Qilu Company as the study subject,a kinetic model for the deacidification reaction was established, and computational fluid dynamics (CFD) method was employed to numerically simulate the two-phase flow of deacidification agent and oil within the pipeline, and the reaction process. Through numerical simulation studies, the influence of static spiral blades and dynamic mixer on mixing effect between deacidification agent and distillate oil was studied. Additionally, an experimental device was constructed to investigate the impact of dynamic mixer on deacidification efficiency. The results indicate that the pre-exponential factor and activation energy in the rate equation for the deacidification reaction are 3.31×10⁷L^2.4/(mol^2.4.s) and 61.6 kJ/mol, respectively. When the mixing effect between the agent and oil is poor, the interfacial area where the interphase deacidification reaction occurs is relatively small, thereby limiting the progress of the deacidification reaction. After enhancing the mixing effect of the deacidification agent and oil phases using spiral blades, the deacidification agent can disperse more effectively in the distillate oil, expanding the agent-oil interfacial area and increasing the region for interphase deacidification reactions. Consequently, on the basis of an unchanged intrinsic deacidification reaction rate, the production of deacidification products increases nearly fourfold. The homogenizer can effectively improve the deacidification efficiency. When the rotational speed exceeds 2 000 r/min, the increase in deacidification efficiency significantly diminishes, indicating that the deacidification reaction is then controlled by the intrinsic reaction rate of the deacidification process.

Key words: distillate oil, deacidification reaction, two-phase flow reaction, CFD simulation, high acidity crude oil, dynamic mixer, spiral blades