External heating forced circulation evaporator
Thread Content
In external heating forced circulation evaporators, in order to prevent the solution from boiling in the heating chamber, the height difference between the liquid level in the evaporation chamber and that in the heating chamber should be around 5 meters. Could everyone share their opinions on this?
First of all, the original poster should break the sentences into proper parts first; it’s hard to read! To address this issue, I think it is by means of the difference in liquid levels; due to the difference in static pressure, the boiling point of the solution varies, which allows it to be prevented from boiling in the heating chamber.
Hehe, it is a bit long indeed. There are various ways to address this issue, but is 5m considered a high value for actual production? So, what is the actual height of the evaporators that everyone here has encountered or designed?
It depends on your actual situation; based on the properties of the material being heated and the heat transfer capabilities of the equipment, a margin needs to be reserved after making calculations. This is just a qualitative analysis that can be done in this way~
If the installation height isn’t sufficient, then how do you plan to achieve it, OP?
I have seen some forced-circulation evaporators on site, but the liquid level difference is less than 5 meters, which also puzzles me
What’s upstairs? It is necessary to clarify the purpose of using both to determine the liquid level difference; as long as that purpose is achieved, it’s sufficient. There are multiple factors that affect whether a solution boils, and the hydrostatic head is just one of them. The height of 5 meters is based on certain principles; it’s not an arbitrary value – 5 meters is the appropriate height.
In external heating forced circulation evaporators, to prevent the solution from boiling in the heating chamber, the height difference between the liquid level in the evaporation chamber and the liquid level in the heating chamber (more precisely, the upper tube sheet of the heater) should be around 5 meters. Since the original poster mentioned that this height difference is intended to prevent the solution from boiling in the heating chamber, it’s not difficult to determine this difference; it’s not necessary for it to be 5 meters high. To ensure the evaporation rate, the heat load on the heating chamber of the evaporator is constant; at a certain circulation rate, in order to ensure that the heater can supply this amount of heat, the temperature rise of the external circulating fluid in the heating chamber is determined. Taking water as an example, if this temperature increase is 2 degrees, to ensure that vaporization does not occur in the heating chamber, a height difference of around 2 meters or more is sufficient.