Calculation of superheated steam heat
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Steam at 1.1 MPa (absolute pressure) and 250°C is exchanged heat with water to reach 0.4 MPa (absolute pressure) and 120°C as condensate; heat calculations are performed for this process, with a mass of 1 ton considered. Thank you, Haiyou, for your help. It would be best if you could provide the calculation process.
In my opinion, the temperature corresponding to 1.1 MPa of saturated steam is approximately 183°C. Therefore, the steam in question is superheated steam. The saturated temperature corresponding to 0.4 MPa should be 143°C. Thus, the heat released during this process should consist of the heat difference resulting from 1 ton of steam cooling from 250°C to 183°C, plus the latent heat required for 1 ton of steam to change from steam to saturated water at 183°C, plus the heat difference resulting from 1 ton of saturated water cooling from 143°C to 120°C, plus the latent heat required for 1 ton of steam to change from steam to saturated water at 143°C.
Could you describe the phase transition process in detail?
I’m not entirely clear about the process either; it is the steam heat exchange process in the reboiler at the bottom of the distillation tower
The previous steps were as I had thought, but the final part is \"the latent heat for 1 ton of steam to change from steam to saturated water at 143°C.\" ”How can there be a heat-release process from saturated steam to water?
My own calculation is: the heat from the temperature difference as 1 ton of steam cools from 250°C to its saturation temperature of 183°C, plus the latent heat required for 1 ton of steam to change from steam to water at 183°C, plus the heat from the temperature difference as 1 ton of water cools from 183°C to 120°C. My main question is: with the water pressure dropping to 0.4 MPa at the end, how is the heat calculated? I ignored this aspect in the above calculation