Heat exchange efficiency of superheated steam and saturated steam
Thread Content
The last edit to this post was made by The moon sets on the horizon on 2016-1-24 at 11:13. Request for help: Condition: The distillation reboiler is heated by steam; the steam with a pressure of 0.8 Mpa and a temperature of 176°C is generated by high-pressure steam after passing through a temperature-reducing pressure regulator； The steam at 0.6 Mpa and around 170 degrees is generated directly by the waste heat boiler. Which one has a better heat exchange effect? It would be best to include the calculation process, thank you!
Principle: Superheated steam is a bit worse.
I agree with what the teacher from @wiseboy said: when using superheated steam for heat transfer, heat transfer generally occurs through a temperature difference phase first, and only then through latent heat; it is essentially gas-to-gas heat transfer, so the heat transfer coefficient is bound to be lower. Saturated steam can utilize latent heat directly, as there is a phase change involved.
You can consider the initial superheated steam as hot air, with a very low heat transfer coefficient. We require that the superheat entering the heat exchanger not exceed 2°C.