Material balances countercurrent contact

For the countercurrent contact with multiple stages in Fig. 10.3-2, the material-balance or operating-line equation (10.3-13) was derived which relates the concentrations of the vapor and liquid streams passing each other in each stage. In a distillation column the stages (referred to as sieve plates or trays) in a distillation tower are arranged vertically, as shown schematically in Fig. 11.4-1. 

Combine material and energy balances to develop the equation for the operating line for a countercurrent adiabatic gas-liquid contact operation. 

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