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braize6 t1_j5vy5fo wrote

Reply to comment by MTGamer in How hot is the steam coming out of nuclear power plants? by ivy-claw

In power plants, water is under pressure. Increasing the pressure, also increases the boiling point. The water at my plant is around 800 degrees Fahrenheit, yet still a liquid. We do this through a series of enclosed heaters, which actually increases pressure as steam is released, which in turn makes the steam condense back to water at a higher temperature. Our plant does this 3 times. Which then the water goes into the boiler. This process is called superheating. Or known as "superheated steam."

Our throttle pressure is 3500psi. So you can imagine just how hot our water can get before it turns into steam (there's a chart out there if you're curious about pressure and temperature of liquid and steam.) Now let's add that water expands about 1600 times from liquid to steam. The result, is a massive amount of energy.

Edit- I appreciate the feedback, and yes, there are many different processes that are going on, in order to generate power, and the boiler process. I'm trying to simplify, because to explain the entire process I'd need about 50 more pages, as it seems many here also know.

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racer_24_4evr t1_j5wyztb wrote

Superheating is when you take steam that is at the boiling point for the given steam pressure, and heat it further. I believe what you described is preheating feedwater.

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Coomb t1_j5xc81d wrote

More likely it's a combination of preheat/superheat/reheat. If you follow a little packet of water through a plant with feedwater preheat, then superheat, then reheat, you get "three times" through the heater. But the description does leave something to be desired.

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racer_24_4evr t1_j5y59ny wrote

Yeah, in our plant, we have three boiler drums, each with preheating and superheating, as well as a reheat on exhaust steam from the high pressure side of the turbine, so there’s a lot of heat moving.

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braize6 t1_j5y905y wrote

Yes it leaves a lot to be desired, because well, there is. The entire process would take me the rest of the month to specifically explain. If someone is interested in all of that, the info is out there

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braize6 t1_j5y8vnx wrote

Basically, yes. With the result of the preheated feedwater going to the water walls, to the economizer, to the superheater to the..... Honestly I could go on for a while here as you seem to also know lol

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racer_24_4evr t1_j5yc8xx wrote

It’s cool to talk about, people don’t realize how much goes into operating a large high pressure version of a kettle.

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