Several issues with falling film evaporators.
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1. Can falling film evaporators only be used at atmospheric pressure? What is the maximum pressure they can handle? Will 0.6 atm work? 2. Which type of film applicator is considered the best nowadays? What are the advantages and disadvantages of various film applicators? Such as installation difficulty, manufacturing difficulty, price, and so on.
It can also be used under negative pressure; it’s not limited to normal pressure only. The choice of liquid distribution device depends on the type of liquid being used. In large-scale production, multi-layer falling-film type liquid distribution devices are commonly used in falling-film evaporators, as they offer advantages such as simple construction and easy maintenance.
Can it be operated under pressure, for example at a pressure of 6 atm?
It can operate at a pressure of 6 atm; it’s just necessary to check whether the device was designed for such high pressure. In case there are changes in the shell side of the first effect.
I want to learn about falling film evaporators as well! Was it provided? Thank you so much!
Generally, evaporation equipment uses multiple effects in combination; for example, we use a two-effect counter-current falling-film evaporation system. In the first effect, the shell side is supplied with saturated steam at a pressure of 8 kilograms, while in the second effect, the evaporation tank operates under a negative pressure of -0.92 kilograms. Feel free to contact me to discuss this in more detail
What is the piping pressure for your first effect? Is it operated at atmospheric pressure? Thank you. What are the inlet and outlet temperatures as well as the inlet and outlet concentrations at Plant 1 and Plant 2? Thank you. By the way, does a falling film evaporator require feed at boiling point? Is the boiling point calculation not taking into account the temperature difference loss due to the hydrostatic column?
Membrane evaporators can definitely operate under both positive and negative pressure; they are usually used in multiple stages, with the pressure decreasing step by step starting from the first stage, and the last stage is generally under negative pressure! The maximum pressure is related to the capacity of your equipment; 0.6 atm is definitely sufficient. As for the film distributor, a double-layer sieve plate liquid film distributor would be a good choice~