Multieffect distillation for thermally coupled configurations

A systematic method presented draws multieffect configurations for any thermally coupled multicomponent distillation scheme. For ternary mixtures, all the resulting double‐effect configurations are presented for each of the five known thermally coupled configurations. For most feed conditions, some of these configurations often require substantially lower heat duty than the double‐effect configurations derived from conventional distillation schemes, such as direct and indirect splits and prefractionator. Essential features of the resulting multieffect configurations are that some of the product streams are produced from more than one distillation column and the transfer of at least one mixture stream takes place between intermediate locations in the distillation columns. This method opens up many more multieffect distillation possibilities for multicomponent feed mixtures.