Pressure-drop correlations packed tower

Figure 1337. Corn-elation of flow rates, typical pressure drop behavior, and packing factors of random packed beds. [Eckert, Foote, and Walter, Chem. Eng. Prog. 62(1), 59 (1966) Eckert, Chem. Eng. 14 Apr. 1975)]. (a) Correlation of flow rate and pressure drop in packed towers, (b) Typical pressure drop data 2 in. porcelain intalox saddles, with F = 40, in a bed 30 in. dia by 10 ft high, (c) Packing factors, F, of wet random packings-...

Many methods have been proposed for estimating pressure drop in packed towers. Most of these methods are based primarily on experimental data obtained with countercurrent flow of water and air through various types of packed towers. Because of the empirical nature of these correlations and the fact that the effects of some of the variables are not included, it is always best to predict pressure drops in the design of packed towers on the basis of experimental data obtained with equipment operating under conditions equivalent to those involved in the design. If such data are not available, approximations can be made by using the methods outlined in the following discussion. 

Figure 7-14. Correlation of flow rate and pressure drop in packed towers. Source Eckert [15].

Figure 9-21F. Strigle s latest generalized pressure drop correlation. Note G = gas mass velocity, Ib/ft -sec. Used by permission of Strigle, R. F. Jr., Packed Tower Design and Applications Random and Structured Packings, 2nd ed. Gulf Publishing Co., (1994) p. 19.

Revised Packed Tower Pressure Drop Correlation Constants for Towers Operating Below Flooding Region... 

Leva, M., "Reconsider Packed-Tower Pressure-Drop Correlations, Chem. Eng. Progress, V. 88, No. 1 (1992), p. 65. 

Leva M. Reconsider packed tower pressure drop correlations. Chem Eng Prog 88 65-72, 1992. 

Figure 3.9 Generalized pressure-drop correlation, upper and lower curve limits. (From J. S. Eckert, Design Techniques for Sizing Packed Towers, Chem. Eng. Progress 57(9), 1961. Used by permission of Chemical Engineering Progress.)...

Figure 8.19 The latest version of the GPDC pressure drop correlation, (a) The latest log-log version of Eckert s correlation, as presented by Strigle (15). (Part a from Ralph F. Strigle, Jr Random Packings and Packed Towers. Copyright 1987 by Gulf Publishing Company, Houston, Texas. Used with permission. All rights reserved.)...

Which method to use. Section 8.2.8 draws attention to the systematic nature of the limitations of packed-tower pressure drop correlations. Due to this systematic nature, the author warns against basing packing pressure drop calculations on any correlations whose limitations are not well known. Section 8.2.8 presents three correlations and elaborates on their limitations and application boundaries. Within their boundaries, these correlations should give reliable predictions. UBe of any other correlation is dangerous unless its limitations are explored. 

FIGURE 8.18 Generalized pressure-drop correlation for packed towers. Note Parameter of curves is pressure drop in inches of water per foot. Numbers in parentheses are millimeters of water per meter of packed height. 

Calculate the tower diameter. Various methods are available for the design and rating of packed towers. The method shown here is an extension of the CVCL model, which is more fundamentally sound than the generalized pressure drop correlation (GPDC). The basic flooding... 

Figure 9-21D. Loading, flooding and pressure drop correlation (one of earlier versions). Adapted by permission from Leva, M. Tbwor Packing and Packed Tower Design, 2nd ed. U.S. Stoneware Co.

FIG. 14-55 Generalized pressure drop correlation of Eckert as modified by Strigle. To convert inches HjO to mm HjO, multiply by 83.31. (From Packed Tower Design and Applications by Ralph E. Strigle, Jr Copyri t 1994 by Gulf Publishing Co., Houston, Texas. Used with permission. All Tights reserved.)... 

BsW, H.Z., Distillation Design, McGraw-Hill, New York (1992). leva, M., Reconsider Packed-Tower Pressure-Drop Correlations, Eng. Prog., 88 (1), 65-72 (1992). 

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