Petlyuk columns advantages

The modifications of Petlyuk column in Fig. 6.12c,e,f are thermodynamically equivalent. The modification in Fig. 6.12e has the advantage that vapor flow from the second three-section column is selected in the top and some middle cross-section, and is directed to the first three-section column (i.e., there are no vapor flows of different directions passing from one column into the other). This allows to keep the pressure in the second column at the level slightly above that of the first one. Therefore, valves allowing to regulate sphtting of vapor flows can be installed at one or both vapor flows. This modification was introduced in the works (Kaibel, 1987 Smith Linnhoff, 1988 Agrawal Fidkowski, 1998). 

In the following section the above advantages and the framework s validity and representational merit will be demonstrated through a GMF/Petlyuk column case study. 

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