General drying considerations

Principle

Drying is an operation that removes some of the solvent from a body, by vaporizing the solvent. The final "dry" product is obtained in a solid form of variable size, possibly in the form of a "divided solid" or powder. The product thus passes from an initial "wet" state, either solid or liquid, to a final "dry solid" state, even if it still contains a residual water (or solvent) content.

The solvent considered is most often water, and we will only present the drying of water here. The same principles can be applied to other solvents, organic for example, but taking into account the properties associated with this solvent (latent heat of vaporization, sorption isotherms, etc.). Mixing several solvents is a more complex case, not dealt with here.

Drying is a "thermal separation" operation,...