Influence of feeding mode on cooling crystallization of L-lysine in Couette-Taylor crystallizer

摘要

A continuous Couette-Taylor (CT) crystallizer was used to apply a multiple feeding mode strategy to enhance the crystal size and size distribution of L-lysine crystals in cooling crystallization. With a 5-min mean residence time, feed concentration of 900 g/l, and rotation speed of 700 rpm, the multiple feeding mode strategy Run-III (D21) produced a large crystal size of 139 mu m and coefficient of variation (CV) for the size distribution of 0.39, both of which were significantly enhanced when compared with the conventional feeding mode Run-I (D1) that produced a crystal size of 82 mu m and CV for the size distribution of 0.53. Essentially, the crystal size was enhanced around 70%, while the size distribution was improved around 28%. Finally, the impact of the multiple feeding mode strategy on the crystal size and size distribution is explained in terms of effective control of the supersaturation.