Horizontal or vertical shell and tube heat exchangers or plate heat exchangers are designed as heating tubes, and the flash tank / separator is located on the upper part of the heat exchanger and circulating pump.
1. Operating principle
Through a circulating pump, the liquid circulates in the column and is heated to overheating at a pressure higher than the normal boiling point of the liquid. After entering the separator, the liquid pressure drops rapidly, resulting in partial liquid flash or rapid boiling. As the circulation of liquid is continuously maintained, the flow rate and temperature in the pipe can be controlled to meet the requirements of corresponding products without being dominated by the preselected temperature difference.
2. Characteristics
Long operation cycle – the boiling / evaporation process is not on the heating surface, but in the separator. Therefore, the scaling phenomenon caused by crusting and sedimentation in the tube is minimized.
The optimized heat exchange surface – the flow rate in the pipe is determined by the circulating pump.
3. Scope of application
It is suitable for easy scaling liquid and high viscosity liquid. It is used as a high concentrator in multi effect evaporation device.
Forced circulation evaporator is very suitable for crystallization evaporator of salt solution.