A evaporator is important system to  to concentrate solution. Keda machinery has developed and improved the structure of evaporator for concentrating heat-sensitive materials, especialy gelatine solution. The three-effect falling film evaporator was unprecedentedly used in gelatine concentration process by Keda Machinery, and it has been proved that it is the best one in gelatine production.
     In the process, the thin solution loads on the top from the pre-heater, and then flows downwards by gravity as a continuous film. It will create a film along the tube shells, progressing downwards. And evaporation happens in the heat exchanger. After the first-effect evaporating, the steam and concentrated solution are separated in the separation tank, and the solution is pumped to next section.