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 Production of steam


To explain some terms, which we use here, we attach a diagram which shows how the steam is produced.

The diagram shows 3 stages, while water is transformed into superheated steam.
The vertically axis of temperature starts with freezing temperature. The second point it is both 100oC and boiling point (at atmospheric pressure).
This point grows every time when the pressure grows and decreases when the pressure diminishes. The last temperature point replies to superheated steam
The horizontal axis of the diagram shows three stages of warmth content in steam, “h” is a sensible heat of water, “I” is a next stage – latent heat needed to change the state of matter – transformation from water to steam, without temperature increase.

Latent heat depends on temperature and while the pressure increases the latent heat insignificantly diminishes.

At the third stage, which replies to superheated steam, every growth of warmth is connected with direct increase of temperature.

Relationship between humidity and steam – it is often used term – relates to proportion of latent steam fraction.

If the humidity level amounts to zero then the steam is dry – and this is that what we need and any amount of heat added in this moment would bring about transformation into superheated steam.
If steam contains some fractions of humidity it means, that water is delivered as suspension and we deal with wet steam.

We have already stressed that it is needed to use dry steam or superheated steam, but absolutely avoid wet steam.

Practically, temperature in connection with pressure let us know with what kind of steam we deal.