Solving Distillation Columns on the H-X Diagram

Binary distillation columns are solved on the H X diagram by graphically imple- 

Starting the calculations at the top of the column, an energy balance around the condenser is written as 

an energy balance is written around the top two stages  

Stream L2 coordinates (X2, ho) are determined by the intersection of the tie line through (Y2, H2) and the saturated liquid curve. Stream V3 coordinates (T, Hj) lie at the intersection of the operating line through D and L2 and the saturated vapor curve. 

This procedure is repeated for all trays above the feed. For operating lines relating passing liquid and vapor streams, L, and Vy+ below the feed tray, the energy balance is performed around the top j trays that include the feed  

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