Adsorptive solvent recovery

To best understand adsorptive solvent recovery we have to consider some fundamentals of adsorption and desorption. In a very general sense, adsorption is the term for the enrichment of gaseous or dissolved substances (the adsorbate) on the boundary surface of a solid (the adsorbent). On their surfaces adsorbents have what we call active centers where the binding forces between the individual atoms of the solid structure are not completely saturated. At these active centers an adsorption of foreign molecules takes place. 

Basic arrangement of adsorptive solvent recovery with steam desorption.. . . 1515... 

Adsorptive solvent recovery units have at least two, but usually three or four parallel-eonneeted fix-bed adsorbers whieh pass sueeessively flirough die four stages of the operation eyele. " ... 

Adsorptive solvent recovery with steam desorption and condensation units with gravity separator and a stripper have become a standard practice in modem production plants. The solvents-laden air (toluene, xylene) is collected from emission points, e.g., rotogravure printing machines, drying ducts by means of a blower and passed through the recovery plant. 

In 1995, one of Europe s most modem printing shops in Dresden was equipped with an adsorptive solvent recovery system (Supersorbon process (Figure 22.1.18.)). 

---