Experiment and simulation of the effect of stirrer blade on the purification of p-cresol by tower continuous crystallizer

The design of stirrer blade is investigated to solve the shortcomings of continuous melt crystallization, such as discontinuous crystal bed and crystallizer blockage. Through experiments and computational fluid dynamics simulations, it was determined that the crystallization bed was the key factor affecting the purification effect. A three-stage structure for the stirrer blade was proposed, consisting of a rushton turbine, a special type of helical ribbon impeller, and an impeller. The optimal parameters were established by single-phase flow simulation as an agitator blade radius of 19 mm, a propeller blade height of 25 mm, a propeller series of 5, and a stirring speed of 120 rpm. The two-phase flow simulation further verified the feasibility of the three-stage stirring structure. The optimized stirrer blade effectively ensured the height and continuity of the crystal bed. This provides the basis for achieving continuous crystallization and promotes the development of industrial separation technology.