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[Venkat @89]

It is quite simple to calculate heat required for pure components heating and boiling purpose, which needs sensible and latent heat cominbedly.

As phase change happens at constant temperature, total heat calculation for vaporization of pure liquids is very straight forward. Evaluating sensible and latent heat parts are easy.

Coming to vaporization or boiling of Binary or Multi component liquid mixtures

As the boiling of liquid mixture doesn't happen at constant temperature, but happens with in the range of temperature, that is starting from Bubble point to Dew point of the liquid mixture.

So,it poses confusion during calculation of sensible and latent heat parts for liquid mixtures

Q1. In calculation of sensible heat for liquid mixtures, should we consider the temperature difference between existing temperature of the liquid mixture and bubble point of the liquid mixture, or difference of existing temperature and dew point Temperature of the mixture?

Q2. Coming to specific latent heat of individual components in the liquid mixture, should we consider specific latent heat at the existing pressure of the mixture directly, as pressure is constant, or do we need to choose any alternative way for specific latent heats of individual components,as temperature is varying while boiling?

Kindly guide me.

Supporting documents of calculations would also help(Reboiler duty), thanks.

Edited by Venkat @89, 24 February 2023 - 04:35 PM.

[Pilesar]

A1. Sensible heat of liquid would be to the bubble point.

A2. For heat exchanger design, it is useful to supply heating curves at more than one pressure that span the range of conditions.