What does "superheated steam" mean?

Superheated steam refers to steam that has been heated beyond its saturation temperature at a given pressure. At this point, the steam exists in a state with no liquid water present, and it can be used for various industrial applications, especially in generating work in turbines or in heat transfer processes.

When water is heated to its boiling point at a specific pressure, it reaches its saturation temperature, resulting in saturated steam, which may still contain water droplets. By continuing to heat this steam beyond its saturation temperature, it becomes superheated, thus enhancing its energy content and improving its efficiency for processes where moisture must be avoided. This characteristic is important in various applications as superheated steam carries more energy and does not risk damaging machinery by introducing moisture.

In contrast, steam containing water droplets indicates it is not superheated, and steam at a temperature below the refrigerant saturation is not relevant to the concept of superheated steam. Likewise, steam that has reached atmospheric pressure may not necessarily define its temperature or state, as it could still be saturated and not superheated.