Design and Energy Performance of Alternative Schemes to the Petlyuk Distillation System

Review of Retrofitting Distillation Columns Using Thermally Coupled Distillation Sequences and Dividing Wall Columns to Improve Energy Efficiency

“…Such systems have been studied for the separation of ternary mixtures and have been shown to provide significant energy savings with respect to both the conventional direct and indirect distillation sequences. The three most widely analyzed thermally coupled systems are the sequence with a side rectifier, the sequence with a side stripper, and a fully thermally coupled system (or Petlyuk column), which are illustrated in Figures 4(a), (b), and 5, respectively (Glinos et al, 1986;Fidkowski and Kró-likowski, 1990;Triantafyllou and Smith, 1992;Hernández and Jiménez, 1996;Jiménez et al, 2003). Of the above possible thermal coupling arrangements, the side stripper and side rectifier have been used widely in refinery distillation and cryogenic air separation, respectively (Seidel, 1935;Watkins, 1979;.…”

Analysis of dynamic properties of alternative sequences to the Petlyuk column

“…The other four new arrangements are obtained through a reduction in the number of interconnections of the original Petlyuk scheme; to accomplish this, the addition of a condenser or a reboiler in the prefractionator is required. Jiménez et al (2003) have reported a study on the design and optimization of the operating conditions to achieve minimum energy consumption for the schemes of Fig. 2, and found that such new systems can provide similar energy efficiencies as the original Petlyuk system.…”

“…1c. To provide a consistent comparison of the alternate schemes with the Petlyuk column, the remaining degrees of freedom for each arrangement were also used to detect the operating conditions that provided minimum energy consumption for each case; the details of the procedure are available in Jiménez et al (2003).…”

“…Design specifications for product compositions included 98.7% purity in A, 98% purity in B and 98.6% purity in C. The columns of the conventional sequence (prefractionator and binary splits A/B and B/C) that provide the tray structure for the Petlyuk system (Hernández & Jiménez, 1999b) were designed assuming reflux ratios of 1.3 times the minimum values. The design pressure for any required column was chosen so that the condenser could be operated with cooling water (Jiménez et al, 2003).…”

“…As a result, several modifications on its structure have been proposed, some of them providing simpler designs that might be more operable than the original Petlyuk configuration, for instance, through the elimination of one of the thermal couplings. Some of the newer structures that have been suggested to improve the expected control properties of the Petlyuk system have recently been analyzed in terms of their potential energy requirements, and found in many cases to provide similar energy savings as the original system (Jiménez, Ramírez, Castro, & Hernández, 2003). Such results provide an incentive for the analysis of the dynamic properties of the new designs to see how they may improve the controllability properties of the Petlyuk configuration.…”