Consequences of property errors on the design of distillation columns

In modem design simulators, the initial input for the estimation of the pha se behaviour of mixtures is a series of characteristic parameters of the pu re species, such as the normal boiling point T-b, the critical temperature T-c and the critical pressure P-c. For many components encountered in pract ice, these parameters are not available from experiment, and therefore, the y must be estimated. The study of the propagation of errors in these estimated parameters throug h to the final design of an item of process plant - a distillation column s eparating binary and ternary mixtures - is the purpose of the present work. The likely magnitude of uncertainties in the input T-b, T-c and P-c is gen erated by the application of several popular and accepted methods. Considerable uncertainties in the predicted designs are demonstrated. Great er attention should be devoted to the development and employment in modem s imulators of more sophisticated methods ensuring better description of mole cular structures and intermolecular interactions. (C) 2001 Elsevier Science B.V. All rights reserved.