Q: How to distinguish between saturated steam and superheated steam?

A:

Simply put, a steam generator is an industrial boiler that heats water to a certain extent to produce high-temperature steam. Users can use steam for industrial production or heating as needed.

Steam generators are low cost and easy to use. In particular, gas steam generators and electric steam generators that use clean energy are clean and pollution-free.

When a liquid evaporates in a limited closed space, the liquid molecules enter the space above through the liquid surface and become vapor molecules. Since the steam molecules are in chaotic thermal motion, they collide with each other, the container wall and the liquid surface. When colliding with the liquid surface, some molecules are attracted by the liquid molecules and return to the liquid to become liquid molecules. . When evaporation begins, the number of molecules entering the space is greater than the number of molecules returning to the liquid. As evaporation continues, the density of vapor molecules in the space continues to increase, so the number of molecules returning to the liquid also increases. When the number of molecules entering the space per unit time is equal to the number of molecules returning to the liquid, evaporation and condensation are in a state of dynamic equilibrium. At this time, although evaporation and condensation are still proceeding, the density of vapor molecules in the space no longer increases. The state at this time is called saturation state. Liquid in a saturated state is called saturated liquid, and its vapor is called dry saturated steam (also called saturated steam).

If the user wants to achieve more accurate metering and monitoring, it is recommended to treat it as superheated steam and compensate for temperature and pressure. However, considering cost issues, customers can also compensate for temperature only. The ideal saturated steam state refers to the one-corresponding relationship between temperature, pressure and steam density. If one of them is known, the other two values ​​are fixed. The steam with this relationship is saturated steam, otherwise it can be regarded as superheated steam for measurement. In practice, the temperature of superheated steam can be higher, and the pressure is generally relatively low (more saturated steam), 0.7MPa, 200°C steam is like this, and it is superheated steam.

Since the steam generator is a thermal energy device used to obtain high-quality steam, it provides steam generated by two processes, namely saturated steam and superheated steam. Someone may ask, what is the difference between saturated steam and superheated steam in a steam generator? Today, Nobeth will talk to you about the difference between saturated steam and superheated steam.

1. Saturated steam and superheated steam have different relationships with temperature and pressure.
Saturated steam is steam obtained directly from heating water. The temperature, pressure, and density of saturated steam correspond one to one. The steam temperature under the same atmospheric pressure is 100°C. If higher temperature saturated steam is needed, just increase the steam pressure.
Superheated steam is reheated on the basis of saturated steam, that is, steam produced by secondary heating.Superheated steam is saturated vapor pressure that remains unchanged, but its temperature increases and its volume increases.

2. Saturated steam and superheated steam have different uses
Superheated steam is generally used in thermal power plants to drive steam turbines to generate electricity.
Saturated steam is generally used for equipment heating or heat exchange.

3. The heat exchange efficiency of saturated steam and superheated steam is different.
The heat transfer efficiency of superheated steam is lower than that of saturated steam.
Therefore, during the production process, the superheated steam needs to be converted into saturated steam through a temperature reduction and pressure reducer for reuse.
The installation position of the desuperheater and pressure reducer is generally at the front end of the steam-using equipment and the end of the cylinder. It can provide saturated steam for single or multiple steam-using equipment and improve production efficiency.