CHEMICAL ENGINEERING TRANSACTIONS VOL. 69, 2018 A publication of The Italian Association of Chemical Engineering Online at www.aidic.it/cet Guest Editors: Elisabetta Brunazzi, Eva Sorensen Copyright © 2018, AIDIC Servizi S.r.l. I SBN 978-88-95608-66-2; I SSN 2283-9216 Improving the Performance of Towers with Random Packing Izak Nieuwoudt a,* , Patrick Quotson a , Juan Juarez b , Norman Yeh b a Koch-Glitsch, 4111E 37 th St N, Wichita, KS, 67220, USA b ExxonMobil Upstream Research Company, 22777 Springwoods Village Parkway, Spring, TX, USA Izak.Nieuwoudt@KochGlitsch.com Random packing is generally the preferred mass transfer device in towers operating at elevated pressure and/or high liquid rates. The performance of these towers can be improved by using modern random packing with increased capacity or efficiency. INTALOX ULTRA random packing can be used to achieve efficiency or capacity benefits compared to IMTP and other random packing types. In the demethanizer and gas absorber applications discussed in this paper the operating companies were able to significantly increase the capacity of their units without sacrificing separation performance. This allowed operating companies to increase the capacity of their towers by replacing IMTP random packing with INTALOX ULTRA random packing. 1. Introduction About 5 centuries ago scientists began using distillation devices in ethanol/water separations that increased the concentration of ethanol in the distillate by unknowingly generating extended surface area and internal reflux. In the early 1800's distillation trays were invented to harness these advances (Forbes 1948). Later in the 1800's scientists started using elements in the towers that could be described as the forerunners of modern random packing. These packing elements were characterized by a low surface area per unit volume and low void fractions. This limited the performance of towers equipped with random packing. With the advent of metal random packing about 100 years ago this changed, since the thin-walled metal pieces yielded higher void fractions and higher surface area per unit volume. This packing still had fundamental deficiencies which limited the capacity and efficiency. The quest in the last 100 years has been to get the highest rate of mass transfer and the highest hydraulic capacity with the least amount of material. Hundreds of different random packing styles have been introduced, with all purported to address these challenges to some degree. In an attempt to group these packings the terms 1st, 2nd, 3rd and 4th generation were created. These groupings do not do complete justice to the performance of the different packings since experience has shown that that the performance of a packing cannot be based solely on the generation it is assigned. The IMTP random packing, even though not classified as a latest generation packing, is still very popular and has a large installed base due to its good performance. Random packing is the preferred mass transfer device in applications that have high specific liquid rates, the system pressure is high, good separation performance is required, and the system calls for significant operating flexibility in liquid and vapor rates. Structured packing does not give good performance at high pressure and at high liquid rates. Trays can handle high liquid rates and high system pressures, but the operating window is relatively small. About a decade ago Koch-Glitsch embarked on a systematic study of the performance of random packing. Through extensive, novel computational and experimental studies the key items that drive random packing performance were identified. During this project more than 100 novel random packing shapes were studied. The mass transfer performance of a few of the better performing prototypes are compared to 3 rd and 4 th generation random packing in Table 1. From this table it is evident that the performance of the prototypes significantly exceeded that of the commercial random packing available at that time. This extensive study culminated in the development of the INTALOX ULTRA random packing, which exhibits improved performance compared to the prototypes and commercially available packing. (Nieuwoudt et al., 2010; Nieuwoudt et al., 2010, Nieuwoudt et al., 2014).