It is a very well known technology even if it appears that the real process has not been deeply investigated by the Companies involved in this kind of plants. In facts, for the same plant, significantly different consumption and yields are guaranteed by different Companies.

DAMMER, together with a foreign Company leader in the steam regeneration plants, is investigating carefully the regeneration kinetics and the polluted process water treatment in order to improve the steam technology in terms of investment as well as running cost.
The working cycle includes one adsorption phase and one regeneration phase by steam in continuous cycle sequence.

 

The steam regeneration technology is very convenient when the solvents to be recovered are only slightly soluble in water and vice versa (toluene, hexane, chlorinated solvents etc.).

If the solvents and water are mutually soluble then the solvents recovery by distillation becomes more complicated for the presence of heavy compounds and by-products (example: acetic acid coming from the hydrolysis reaction between ethyl acetate and water) and solvents water azeotropic mixture.

Furthermore there is generally a serious problem with the waste water with solvents losses and expensive waste water treatment plants necessity.

Typical specific consumption figures of a steam desorption plant, without distillation, per kg of recovered solvent are the following:

Electrical Energy	0,8÷1,2	kWh
Steam	4÷5	Kg