Binary mixtures enthalpy balances, column

For the case where the total flow rates Vj and Lj vary throughout each section of the column, these flow rates may be determined by solving the enthalpy balances simultaneously with the above set of equations. For binary mixtures, the desired solution may be found by use of either graphical methods (Refs. 10, 13) or the numerical methods proposed in subsequent chapters for the solution of problems involving the separation of multicomponent mixtures. 

A rigorous column simulation requires, besides material balances, the implementation of enthalpy balances. In binary mixtures the enthalpies of gas and liquid streams can be taken from enthalpy/concentration diagrams. 

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