Distillation column targets

Dhole VR and Linnhoff B (1993) Distillation Column Targets, Comp Chem Eng, 17 549. 

Daichendt.. M. M.. and Grossmann. I. E. "Preliminary Screening for the MINLP Synthesis of Process Systems, II. Heat Exchanger Networks," Comput. Chem. Eng. 18, 679 (1994b). Dhole. V. R., and Linnhoff. B. "Distillation Column Targets," Proc. Eur. Symp. Comput. Aided Process Design (Escape-1) (1992). 

Linnhoff, B. Dhole, R. V Distillation Column Targets, Computers and Chemieal Engineering Journal, Vol. 17 (1983), p. 549/560... 

Dhole, V. R., Linnhoff, B. (1993). Distillation Column Targets. Comput. Chem. Eng, 17,549-60. 

In the use of temperature measurement for control of the separation in a distillation column, repeatability is crucial but accuracy is not. Composition control for the overhead product would be based on a measurement of the temperature on one of the trays in the rectifying section. A target would be provided for this temperature. However, at periodic intervals, a sample of the overhead product is analyzed in the laboratory and the information provided to the process operator. Should this analysis be outside acceptable limits, the operator would adjust the set point for the temperature. This procedure effectively compensates for an inaccurate temperature measurement however, the success of this approach requires good repeatability from the temperature measurement. 

In the use of temperature measurement for control of the separation in a distillation column, repeatability is crucial but accuracy is not. Composition control for the overhead product would be based on a measurement of the temperature on one of the trays in the rectifying section. A target would be provided for this temperature. However, at... 

Today, there is an increasing interest in the theoretical study and the practical application of integrated reactive separation processes such as reactive distillation columns [1-3] or membrane-assisted reactors [37]. However, to date there is no general method available for designing such processes. For practical applications, it is important to be able to evaluate quickly whether a certain reactive separation process is a suitable candidate to reach certain targets. Therefore, feasibility analysis tools being based on minimal thermodynamic and kinetic information of the considered system are valuable. 

Operation of distillation columns involves a trade-off between energy use and product recovery. The optimal trade-off determines targets for operating parameters. The operating parameters include reflux ratio, feed temperature, column temperature, reboiling duty, column pressure, and so on. The question is How to achieve the most economic operation of the column ... 

Bandyopadhyay, S., Malik, R.K. and Shenoy, U.V., Temperature-enthalpy curve for energy targeting of distillation columns, Comput. Chem. Eng., 22 (1998) 1733. 

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