Computer Aided Design (CAD) of a Multi-component Condenser

In the case of multi-component condensation the ‘condensing vapour contains a mixture of components having different boiling points, which condense over a wide temperature range, either in presence of or absence of non-condensing material. In this work, a design algorithm for the condensation of a multi-component vapour mixture in shell side of a shell and tube vertical condenser has been developed using Bell and Ghaly’s method. Based on this algorithm, an in-house computer code has been developed. This code was used for the design of the condenser for the condensation of a hydrocarbon vapour mixture containing propane, butane, hexane, heptane and octane in the mole composition of 0.15, 0.25, 0.05, 0.30 and 0.25, respectively. A code was also developed for the Kern’s method for the condenser design. It was found that Kern’s method provides a lesser heat transfer area because Kern’s method does not consider the mass transfer resistance, nor does it take care of handling the sensible heat transfer during condensation. These facts have been incorporated in Bell and Ghaly’s method by taking the one-phase heat transfer coefficient during vapour sensible heat transfer. The effects of operating variables viz. vapour flow rate, coolant flow rate, vapour inlet temperature, and coolant inlet temperature on the overall heat transfer coefficient, and shell side pressure drop have been studied for the wide range of parameters. The results are useful for the design of multi-component condensation.