Plate-type or shell-and-tube for chilled water heat exchangers, 7℃→12℃
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I would like to ask everyone: how can a chiller using chilled water (inlet temperature of 7°C, outlet temperature of 12°C) be used to reduce the temperature of a hot stream from 40°C to 12°C?℃； What kind of heat exchanger is generally used? Can a shell-and-tube heat exchanger be used?
If you mean that the hot material in question is a liquid, then a plate heat exchanger is still a good choice. But the shell-and-tube type can definitely be used as well. If the hot material you are referring to is a gas, then from the perspective of heat transfer and energy consumption, a shell-and-tube design is more suitable. If your hot gas material is not corrosive, I have developed many designs using internal finned heat exchangers (which belong to the shell-and-tube type of heat exchangers). Furthermore, all of the above apply to medium and low pressure conditions; if it is high-pressure hot material, then a shell-and-tube heat exchanger is recommended.
As long as the pressure is not high and it is non-toxic and non-flammable, a plate heat exchanger can be used. Otherwise, a tube shell has to be used
All of them are useful; it depends on the amount of heat transfer required
The hot material is a gas consisting of methane and ethylene in a mixture, at a pressure of 3 MPa. g, flow rate of 30,000 cubic meters
What I really want to ask is whether a shell-and-tube heat exchanger can handle a temperature difference of 5°C; isn’t the minimum temperature difference for such exchangers usually around 8°C?
I suggest that in your next discussion, when replying to a post, simply click on the option to reply to that specific post; this way, the participants will know that you have responded to the question. Otherwise, they wouldn’t even be aware that you replied if they didn’t see any updates to that post. Given this high-pressure gas cooler, it is recommended to abandon the plate heat exchanger option. Therefore, for this operating condition, a shell-and-tube design is definitely the appropriate choice. As for the temperature difference you mentioned, it refers to the difference on the water side, right? If that’s the case, then there is no such thing as a minimum temperature difference of 8 degrees as you said. If you consult earlier design manuals, you will find that the temperature difference on the water side of shell-and-tube heat exchangers was generally specified as 5 to 7 degrees. These empirical values are not part of any established standards; in design, it is sufficient to follow the requirements of the process. There will definitely be no problem running it.