dry steam

[upup]

We were talking this morning and want some answers please.

At a power station the steam must be dry. What happens to the "water".

Then, why do they need to cool the steam back to water and heat it up again.

Is it like gas, cool state it is liquid, then when heated up it becomes like a gas?

 

[HavocXphere]

"Dry" in the power station context still involves vast amounts of water...just less than "wet".

 

[Lukcydog]

We were talking this morning and want some answers please.

At a power station the steam must be dry. What happens to the "water".

Then, why do they need to cool the steam back to water and heat it up again.

Is it like gas, cool state it is liquid, then when heated up it becomes like a gas?

Steam = water in evaporated form. When they talk about dry steam it refers to 100% saturated steam (ie no liquid water present). There are two reasons for dry steam in Power stations:
1. Heat transfer capability of dry steam (Latent heat)
2. Water droplets present in steam cause corrosion of pipe as well as the turbine equipment.

Steam Dryness = 100% - %Entrained Water

LD