Evaporation is the unit operation of concentrated solution. Usually, the solvent is volatile, while the vapor pressure of most solutes approaches zero and cannot be volatile. The process by which a solution is concentrated by removing part of the solvent by vaporization under boiling conditions is called evaporation. In most cases, the evaporator USES steam as the heating medium (usually called heated steam, primary steam or fresh steam). It transfers heat indirectly through the metal wall to the solution. When the solution is heated, the solvent boils and vaporizes.
The material liquid to be concentrated is pumped into the top of the heating tube and the liquid film flows down along the inner wall of the heating tube. During this process, due to heating outside the tube, the liquid film inside the tube begins to boil and partially evaporate. The remaining liquid and steam are separated in a separator at the bottom of the column and downstream.
Reasonable determination of the material and liquid flow rate in the heat exchange tube can avoid the dry tube at the bottom of the heat exchange tube, ensure the thickness of the liquid film, and obtain the best heat exchange effect and the minimum power consumption.
Falling film evaporator can perform both cycle evaporation and one-way evaporation.
◎ Single set of capacity up to 200T/H;
◎ Suitable for heat sensitive materials;
◎ Suitable for low concentration, less solid content, low tendency to scale materials.
◎ High heat transfer coefficient, small temperature difference, vacuum evaporation;
◎ Ensure the material in the heat exchange tube in the appropriate boiling state, avoid the phenomenon of dry wall caused by violent vaporization, scale formation;
◎ The boiling temperature loss caused by the liquid column, small circulation, less power consumption.
◎ High heat transfer coefficient, low temperature difference,vacuum evaporation.
◎ Ensure the material keep boiling in the heat exchange tube avoid drying wall and scaling caused by intense evaporation.
◎ Low circulation volume, low power consumption.
Process Flow Chart