Thirdgeneration Packings

intalox® Metal Tower Packing 0MTP®) (Fig. 8.3a). IMTP® combines the high void fraction and the well-distributed surface area of the Pall® ring with the low aerodynamic drag of the saddle shape. Compared to the Pall® ring, it provides a more open shape and improved liquid spread, while incorporating adequate mechanical strength and entanglement resistance (5). IMTP® is available in metals only. It is marketed exclusively by the Norton Company.

Cascade® Mini-Rings (CMR®) (Figs. 8.3b, 8.4a, 8.5a). These rings are similar to the Pall® ring, but have an aspect ratio (height to diameter ratio) of 1:3, compared to 1:1 in the Pall® ring. The lower aspect ratio orients the particles with their open side facing the vapor flow, thus reducing friction, and exposing more surface to mass transfer (6). CMR® is available in metal, plastic, and ceramics. It is marketed exclusively by Glitsch!, Inc.

The CMR® Turbo is a metallic variation of the CMR® that has perforated walls and tongues. Compared to the normal CMR®, this variation appears to slightly improve both the capacity and the efficiency (3).

Chempak® or Levapak (LVK®) (Fig. 8.3c). Cutting a Pall® ring in half creates this packing. The cutting exposes and activates the concealed

Intalox® Metal Tower Packing (a)

Column Packing Norton Imtp
Figure 8.3 Third-generation random metal packings, (a) Intalox* Metal Tower Packing (IMTP®); (b) Cascade* MiniRing (CMR*). (Part a, courtesy of Norton Company; part b, courtesy ofGlitschf Inc.)

Pall® ring tongues, promoting vapor-liquid contact, mixing, and liquid spread (7). Chempak® is available in metal from Nutter Engineering-Corporation and in plastic and other nonmetals from Chemetics International.

Nutter Rings® (Fig. 8.3d). Nutter Rings® retain the low aerodynamic drag of the saddle shape, while offering a more open structure witk improved liquid spread. The rib-and-hoop design minimizes nesting and interlocking and achieves adequate mechanical strength Iftt Nutter Rings® are available in metal and plastic. They are marketed exclusively by Nutter Engineering Corporation.

HcKp® (Fig. 8.3 e). This packing is a modified Pall® ring with a more open structure and an enhanced arrangement of internal drip tabs (8ou

Drip Ring With TabsDrip Ring With Tabs

J^w® Third-generation metal random packing. (C) Chemoak®-

id) Nutter Ring®. (Parts c and d, courtesy of Nutter Bneineerin/can , P '

J^w® Third-generation metal random packing. (C) Chemoak®-

id) Nutter Ring®. (Parts c and d, courtesy of Nutter Bneineerin/can , P '

Koch Fleximax
Figure 8.3 (Continued) Third-generation metal random packings, (e) HcKp; (/) FLEXIMAX® {Parts e and f courtesy of Koch Engineering Company, Inc.)

It is stated to be ideal for use in high-liquid-rate systems (8a). HcKp® is available in metal exclusively from Koch Engineering Company, Inc.

FLEXIMAX® (Fig. 8.3 f) This packing is an open saddle with well-spread surface area. FLEXIMAX® is available in metal exclusively from Koch Engineering Company, Inc.

Hiflow® ring (Figs. 8.3$, 8.46,8.56). Resembling the Pall® ring but with wider openings, the Hiflow® ring shifts surface from the wall to the center of the ring and reduces resistance to vapor flow (9). The Hiflow® ring is available in metal, plastic, and ceramics from Rauschert Industries, Inc.

Jaeger Tri-Packs® (Figs. 8.3ft, 8.4c). This packing replaces the cylindrical shape of the Pall® ring by a spherical shape. This provides more void space and better distribution of active surface than the Pall® ring and minimizes interlocking (10). Jaeger Tri-Packs® are available in metal (also referred to as Metal Jaeger Top-Pak®) and plastic (also referred to as Hackette®) from Jaeger Products, Inc.

NOR PAC® (NSW) rings (Fig. 8.4d). Replacing the solid walls of the Pall® ring by wide openings in the NOR PAC® is at the expense of losing some surface area. The result is a packing that has (3,11) high

Fleximax Koch Glitsch

Figure 8-3 (Continued) Third-generation metal random packings, (g) Hiflow® ring, ¡hi Jaeger Tri-Packs® (Top-Pak®); U) IMPAC®. (Part g, courtesy of Rausckeri Industries, Inc.; part h, courtesy of Jaeger Products, Inc.; part i, courtesy'of Lantec, Inc.)

Figure 8-3 (Continued) Third-generation metal random packings, (g) Hiflow® ring, ¡hi Jaeger Tri-Packs® (Top-Pak®); U) IMPAC®. (Part g, courtesy of Rausckeri Industries, Inc.; part h, courtesy of Jaeger Products, Inc.; part i, courtesy'of Lantec, Inc.)

capacity at the price of lower efficiency. NOR PAC® rings are available in,plastic from Nutter Engineering Corporation and from Jaeger Products, Inc.

Intalox® Snowllake® packing (Fig. 8.4e). The low aspect ratio (height to diameter), even lower than that of CMR®, orients the Snowflake/® par-

Figure 8.4 Third-generation plastic random packings. (a) Cascade® MiniRing (CMR®J; (6) Hiflow® ring. (Port a, courtesy of Glitsck, Inc.; part b, courtesy of Rausckert Industries, Inc.)

Figure 8.4 Third-generation plastic random packings. (a) Cascade® MiniRing (CMR®J; (6) Hiflow® ring. (Port a, courtesy of Glitsck, Inc.; part b, courtesy of Rausckert Industries, Inc.)

tides with their open side facing the vapor flow. This reduces frictiaB and permits good liquid drainage from the ribs of the packing. Intalox® Snowflake® packing is available in plastic from the Norm Company.

LANPAC® (Fig. 8.4f). This packing has a hollow polyhedron shap^, constructed on an intricate network of ribs, filaments, rods, struts, tmi pointed fingers, all cross-linked and uniformly spaced throughout m

Plastic Tri Pac

Figur« 8.4 [Continued) Third-generation plastic random packings, (c) Jaeger Tri-Packs® (Hackette®); id) NOR-PAC® (NSW rings). (Part c, courtesy of Jaeger Products, Inc.; part d, courtesy of Nutter Engineering Corp.J

Figur« 8.4 [Continued) Third-generation plastic random packings, (c) Jaeger Tri-Packs® (Hackette®); id) NOR-PAC® (NSW rings). (Part c, courtesy of Jaeger Products, Inc.; part d, courtesy of Nutter Engineering Corp.J

open-structural framework. This design gives an open structure with a high surface area, void Of nesting and interlocking. LANPAC® is available in plastic exclusively from Lantec Products, Inc.

IMPAC® (Figs. 8.3/, 8.4g). This is another complex-shaped packing (compared to LANPAC®). It gives as open a structure with an even higher and better distributed surface area (12). IMPAC® is available in metal and plastic exclusively from Lantec Products, Inc.

(0 (g) Figure 8.4 (Continued) Third-generation plastic random packings, (e) Intalox® Snow-flake® packing (f) LAN PAO® (g) 1MPAC® (Part e, courtesy of Norton Company; part* f and g courtesy of Lantec, Inc.)

(0 (g) Figure 8.4 (Continued) Third-generation plastic random packings, (e) Intalox® Snow-flake® packing (f) LAN PAO® (g) 1MPAC® (Part e, courtesy of Norton Company; part* f and g courtesy of Lantec, Inc.)

Others. Miscellaneous random packings are shown in Fig. 8.6.

8.1.4 Comparison of random packings from different generations

Figure 8.7 is a plot of the specific surface area (surface area per unit volume) against the packing factor for metallic packings from each of the three packing generations. The specific surface area is a rough indicator of packing efficiency; the higher it is, the more efficient the packing. Packing factors are indicators of capacity; the lower the

Sulzer Packed Columns

Figure 8.5 Third-generation ceramic random packings, (a) Cascade® MiniRing (CMR®); (6) Hiflow® ring, (Part a, courtesy of Glitsch, Inc.; part b, courtesy of Rausckert Industries, Inc.)

Figure 8.5 Third-generation ceramic random packings, (a) Cascade® MiniRing (CMR®); (6) Hiflow® ring, (Part a, courtesy of Glitsch, Inc.; part b, courtesy of Rausckert Industries, Inc.)

packing factor, the higher the capacity. Packing factors are discussed in detail later (Sec. 8.2.10). Figure 8.7 is based on the following approximations:

1. Specific surface areas were taken from Perry (14) or Strigle (15). When the value given by Perry differed from that of Strigle for the same packing, an average value was used. For most third-gener-ation packings, specific surface areas were given neither by Perry nor by Strigle, and were obtained from the packing supplier literature.

2. For Raschig rings, packing factors were taken from Perry (14) and Strigle (15). For second- and third-generation packings, packing

Raschig Rings

Figure 8.6 Miscellaneous random packings, la) VSP*. (i>)lnterpack* (Parts a and b courtesy of Jaeger Products, Inc.)

Figure 8.6 Miscellaneous random packings, la) VSP*. (i>)lnterpack* (Parts a and b courtesy of Jaeger Products, Inc.)

factors were derived from Table 10.1, Some of the packing factors derived from Table 10.1 were modified to give better fit to experimental data shown in Chapter 10.

Due to the approximations, Fig. 8.7 is unsuitable for comparative evaluation among different third-generation packings. References to the manufacturers have therefore been omitted. The values plotted on Fig. 8.7 were arbitrarily connected by straight lines.

Figure 8.7 shows that at a constant capacity (i.e., a constant packing factor), each generation of packing enhanced the specific surface area. Similarly, at a constant specific area, packing capacity increased from generation to generation. This signifies improvements in either capacity or efficiency or both from one generation to the next. The improvements from the first to the second generation have been mayor.

(d)

Rgur« 8.6 {Continued) Miscellaneous random packings, (c) Tellerette* packing; <d) Maspac® packing {Parts c and d from "Random Packings and Packed Towers—Design and Application," by Ralph F. Strigle, Jr., Copyright © 1987 by Gulf Publishing Company, Houston, Texas. Used with permission. All rights reserved.)

Rauschert Hiflow

Figure 8.6 (Continued) Miscellaneous random packings, (e) Dinpak®; tf) SuperToro^ Saddle; tgi Hiflow® Saddle; <,h) Ralu® Ring; (i) ENV1PAC®; <j) Super Levapak (S-LVK*l (Parts f, g and h from R. Billet, Packed Column Analysis and Design, Ruhr UnivertOy Bochum, 1989. Reprinted courtesy of Ruhr University; parts e and i, courtesy of Eniiem Engineering GmbH. Part j, courtesy of Chemetics International.)

Figure 8.6 (Continued) Miscellaneous random packings, (e) Dinpak®; tf) SuperToro^ Saddle; tgi Hiflow® Saddle; <,h) Ralu® Ring; (i) ENV1PAC®; <j) Super Levapak (S-LVK*l (Parts f, g and h from R. Billet, Packed Column Analysis and Design, Ruhr UnivertOy Bochum, 1989. Reprinted courtesy of Ruhr University; parts e and i, courtesy of Eniiem Engineering GmbH. Part j, courtesy of Chemetics International.)

Impac Packing Lanpac
Figur* 8.7 Performance comparison of the three packing generations: specific surface area versus packing factor.

those from the second to the third generation have been far less pronounced. The improvements from second to third generation appear to be more noticeable in smaller than in larger packings.

Figure 8.7 also shows that not all third-generation packings increase capacity and efficiency compared to second-generation packings. For instance, data for one third-generation packing fall right on the line for the second-generation packings. There is some uncertainty, as data reported for some third-generation packings are based on limited tests.

Was this article helpful?

0 0

Post a comment