Problems with evaporative heat exchangers
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There is currently a heat exchanger that uses a 60°C ethylene glycol solution to heat liquid ethylene from -104°C to -27°C as liquid. Can this same heat exchanger be used to heat liquid ethylene from -104°C to -27°C to -20°C as gaseous ethylene? Thank you all, guys! :( :( :(
It’s that type of heat exchanger; it’s necessary to calculate whether it’s sufficient
The problem should not be serious, as the total heat transfer amount can be increased by raising the flow rate of the hot fluid! ! This can meet the needs!
The information provided by the poster is too limited to make an estimate. First, the area of the existing heat exchanger as well as the flow rates of the fluids on both sides are needed, along with the desired pressure drop; only then can it be determined more easily. Overall, however, it’s likely that the area is insufficient. As stated by the poster, previously there was only sensible heat involved, but now there is also latent heat, and typically the value of latent heat is quite high. Even if it were possible to proceed, the flow rate would not reach the level intended in the original design, which would result in a reduced production capacity. This post was last edited by eddy-8280103 on 2009-2-11 08:23.]
I'm sorry! The question isn’t very clear. The heat input and heat exchange area are fine; it’s possible to reduce the amount of ethylene that vaporizes. My question is whether there are any special requirements regarding the wall thickness and strength of the tubes in the heat exchanger. Thank you!
The heat transfer power, heat fluid flow rate, cold fluid outlet (volume) flow rate, heat transfer area, and so on can all experience significant changes. Therefore, the original heat exchanger finds it difficult to meet the requirements. It is best to make a decision after conducting detailed calculations.
It should be usable, but it’s difficult for the heat exchanger to meet the requirements; it’s best to make a decision after conducting detailed calculations.
If your original heat exchanger design was reasonable, then it absolutely cannot be used； First, to heat liquid ethylene at -104°C to gaseous ethylene at -27 to -20°C, the amount of heat required is greater than that needed to heat it to -27°C in its liquid state ； Moreover, even if heat can be extracted and turned into gas, it will directly affect the area of the heat exchanger; the processes of heat exchange between liquid and gas versus liquid and liquid, as well as the principles of heat exchange and temperature differences, are all different ； So neither plate heat exchangers nor shell-and-tube exchangers will work ；