Application of the Wallis Plot for the Determination of the Loading Limits of Structured Packings and Sandwich Packings

• Main Authors: O. Yildirim, S. Flechsig, U. Brinkmann, E.Y. Kenig
• Format: Article
• Language: English
• Published: AIDIC Servizi S.r.l. 2015-09-01
• Series: Chemical Engineering Transactions
• Online Access: https://www.cetjournal.it/index.php/cet/article/view/4602

Structured packings are widely used in many separation units in the chemical process industry. One of the innovative modifications of structured packings is the so-called sandwich packings, which consist of two packing layers with different geometrical surface area. Fluid dynamic parameters, such as the flooding point, are essential for the design of packed columns. The Wallis plot is an empirical method to provide a flooding point correlation based on experimental data. In the present work, experimental results obtained with common structured packings manufactured by Montz and Sulzer as well as with sandwich packings manufactured by Montz were used. From the pressure drop data for both packing types, the gas and liquid loads under flooding conditions were determined. Parameters of the Wallis equation were adapted, and a correlation was proposed allowing the loading limits of structured packings and sandwich packings to be described in a reliable way as functions of the geometrical surface area, declination angle to the vertical as well as physical properties. The Wallis equation was implemented into a fluid dynamic model for the description of the pressure drop of sandwich packings (Brinkmann et al., 2012). By this way, the range of application of the model was extended and the predictivity improved.