Effectiveness of mass transfer in a packed distillation column in relation to surface tension gradients

✍ Scribed by W.B. Patberg; A. Koers; W.D.E. Steenge; A.A.H. Drinkenburg

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 582 KB
• Volume: 38
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(83)80013-x

✦ Synopsis

Ah&act

-In packed columns large differences occur in the wetting of the particles and especially in the refreshing of the liquid 011 the wetted particles due to gradients in surface tension of the liquid/gas interface. Mass transfer rates may die, with a factor 2. In a column packed with Berl saddles distillation experiments were performed with a mixture n-heptane/cyclohexane. Ceramic Berl saddles of 4, 6 and 10 mm were used as well as aluminum Berl saddles of 4 mm. In some of the experiments the saddles were coated with PTFE (teflon). The driving force for mass transfer was varied over a wide range. Both negative and positive driving forces were realized. The influence of the surface tension driven refreshment of the interface is most pronounced for small particles; for larger liquid flow rates. that may be applied in beds with larger particles, the effect is obscured by the inertia of the downcoming liquid.