[yi y2 2 yNcl5 T f P Xi X2 2 xNci [y T f P x

Here we have introduced the mole fractions x and y in the liquid and vapour phases respectively, and we trivially have £1 xi = 1 and £ 1 yi = 1.

In ideal mixtures, the VLE can be derived from Raoult's law which states that the partial pressure p, of a component (i) in the vapour phase is proportional to the vapour pressure (po) of the pure component (which is a function of temperature only: po = po(T)) and the liquid mole fraction (x,):

Here po(T) depends on temperature so the K-values will actually be constant only close to the column ends where the temperature is relatively constant. On the other hand, the ratio po(T)/po(T) is much less dependent on temperature, which makes the relative volatility very attractive for computations. For ideal mixtures, a geometric average of the relative volatilities for the highest and lowest temperature in the column usually gives sufficient accuracy in the computations: « = y«ij,top ' ^.bottom.

We usually select a common reference component r (usually the least volatile or heavy component), and define:

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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