Internal Mass Flows in Sequences of Simple Distillation Columns

5 Internal Mass Flows in Sequences of Simple Distillation Columns 

Take two different sequences for the separation of a four-component mixture (Fig. 5.7). Summing the feed flow rates of the key components to each column in the sequence, the total flow rate is the same in both cases  

However, the flow of nonkeys is different. The arrangement shown in 

However, the case shown in Fig. 5.76 has a flow rate of nonkeys given by 

In general, the flow of key components is constant and independent of the sequence, while the flow of nonkey components varies according to the choice of sequence, as illustrated in Fig. 5.8. 

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