Is the temperature superheated after depressurization of saturated steam?
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Dear experts, could you please help calculate how much the temperature will be superheated after depressurization, assuming an isenthalpic process? The saturated steam pressure is 25 barg before depressurization, with a flow rate of 1200 kg/h; after depressurization, the pressure drops to 12 barg Please help calculate it ；
Two methods are determined. The first is software simulation, and the second is querying using software for steam properties
Two methods are determined. The first is software simulation, and the second is querying using software for steam properties
Does anyone have the Aspen software to help with the simulation? Thanks
The depressurization of steam simply means that the pressure decreases while the temperature remains unchanged. However, compared to the vapor pressure at that pressure level, the temperature is too high; that’s why it’s called superheated steam... For example, the saturation temperature of steam at 41K is 253°C. When the pressure is reduced to 30K (the normal saturation temperature being 234°C), the actual temperature still remains at 253°C... This is 253–234 = 19 degrees higher than the theoretical value, meaning the steam is superheated by 19 degrees...
There is a Morrell curve that can be used for comparison
I have steam calculation software; feel free to message me if you need it
When steam is depressurized, the pressure drops, but the temperature remains unchanged, right?... Why do some people still claim that the temperature also decreases? A utility plant produces steam at high pressure and high temperature, while you use steam at relatively lower pressure. Isn’t it necessary to install a pressure control valve and a desuperheater? Is it required to add water to lower the temperature? Then why lower the temperature? It’s because after depressurization, the temperature becomes superheated. Do you understand? What happens when there is superheating? Your pipelines and equipment surely have specified design temperatures, right? I have no objection to criticizing others... but please make sure you understand things first, okay?
It’s overheating; it’s a cooling process after passing through the pressure relief valve