Natural-circulation evaporator

The solution in the natural external circulation evaporator circulates by the density difference of the feed liquid: the liquid is heated in the heating chamber tube, the temperature increases, the density decreases, and the density difference with the cold solution in the circulation pipeline causes the liquid to circulate upward in the heating tube and downward in the circulation tube. The heated solution enters the evaporation chamber in the form of sensible heat for flash evaporation and cooling. Afterwards, it enters the circulation tube downwards and undergoes cyclic heating and evaporation.
The circulation speed of natural circulation evaporation solution in the equipment is not high, generally less than 1 meter/second. To prevent scaling and crystallization, the heating tube should be operated in a completely submerged state. This evaporator is suitable for concentrating solutions with less severe scaling and less corrosiveness. Its advantages are simple structure, easy manufacturing, and low power consumption. The disadvantage is that the solution circulation speed is slow and not suitable for materials with high viscosity and a large amount of crystallization. It cannot be cleaned on site and the material is heated for too long, making it unsuitable for heat sensitive materials.