Distillation design

Optimization. Optimi2ation of the design variables is an important yet often neglected step in the design of extractive distillation sequences. The cost of the solvent recovery (qv) step affects the optimi2ation and thus must also be included. Optimi2ation not only yields the most efficient extractive distillation design, it is also a prerequisite for vaUd comparisons with other separation sequences and methods. 

Baird [Comp. Chem. Engng., 9, 593 (1985)]. Since then, they have been applied successfully to problems involving interlinked distillation (Wayburn and Seader, op. cit.), azeotropic and three-phase distillation [Kovach, 111 and Seider, Comp. Chem. Engng., 11,593(1987)], and reac tive distillation [Chang and Seader, Comp. Chem. Engng., 12, 1243 (1988)], when SC and inside-out methods have failed. Today, many computer-aided distillation-design and simulation packages include continuation techniques to make the codes more robust. 

Extractive Distillation Design and Optimization Extractive distillation column composition profiles have a veiy characteristic... 

Use of HETP Data for Absorber Design Distillation design methods (see Sec. 13) normally involve determination of the number of theoretical equihbrium stages or plates N. Thus, when packed towers are employed in distillation appRcations, it is common practice to rate the efficiency of tower packings in terms of the height of packing equivalent to one theoretical plate (HETP). 

For multicomponent mixtures the method of Hengstebeck can be used. Kister s book Distillation Design, by McGraw-Hill, 1992 explains the method and is easier to find than the original book of Hengstebeck. 

Frank, O., Shortcuts for Distillation Design, Chemical Engineering, March 14, 1977. 

Kister, H. Z., Distillation Design, McGraw-Hill, New York, 1992. 

Distillation design is based on the theoretical consideration that heat and mass transfer from stage to stage (theoretical) are in equilibrium [225-229]. Actual columns with actual trays are designed by establishing column tray efficiencies, and applying these to the theoretical trays or stages determined by the calculation methods to be presented in later sections. 

Recommended Range of Application. The Kister and Haas [184] Flood Correlation (used by permission, Kister, H. Z., Distillation Design, McOraw-HiU, Inc., 1992)... 

Guerreri, G., Bruno Peri, and F. Seneci, Comparing Distillation Designs, Hydrocarbon Processing, Dec. (1972), p. 78. 

A receiver for low pressure distillations designed by G. A. R. Kon (1930) is quite easy to make the joints D and C (Figure 61) are both standard B.19 joints the two taps at A andRare standard designs of three-way taps. For the part G a tube of about 3 cm diameter... 

The mass balance of these designs is given in Table 33.2, while Table 33.3 shows a comparison between the base case and the heat-integrated alternative, in terms of energy requirements. Compared to the conventional reactive distillation design, the energy requirements in the heat-integrated case are further decreased with... 

Chang, H-Y. (1980) Hyd. Proc. 59 (Aug.) 79. Computer aids short-cut distillation design. 

Devise a superstructure for a distillation design involving a single feed, two products, a reboiler and a condenser that will allow the number of plates in the column itself to be varied between 3 and 10 and at the same time vary the location of the feed tray. 

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