The crystallizing tank is made of imported **6L or **4 stainless steel. The internal wall adopts electrolytic mirror polishing or mechanical polishing. The external wall adopts **4 completely welding structure for heat preservation. The exterior surface adopts mirror polishing or semi-luster polishing. A 0.2µm ventilation hydrophobic filter is installed on the crystallizing tank. The crystallizing tank can endure **1c high temperature sterilization, equipped with sanitary pressure meter. The outside connection of the tank body adopts sanitary rapid open connector. The crystallizing tank is equipped with temperature monitoring device, 2 view mirrors, cleaning ball and nitrogen inlet. The shaft seal adopts special sanitary mechanical seal to guarantee the material is out of pollution. The crystallizing tank can adopt frequency conversion speed control device and the rotation speed of mixing shaft has wide regulation range.