Distillation column revamp using DWC technology Dividing wall column technology presents a straightforward, economical, and efficient solution that plays a crucial role in energy efficiency initiatives
Rajeev Ranjan and Minaz Makania KBR Anish Chakraborty and Naveen V Nair BPCL
D istillation remains one of the most However, conventional distillation operations consume a significant portion of the total energy required in a process. Dividing wall column (DWC) technology presents a compelling alternative to traditional distillation column schemes, offering substantial savings in both operating and capital costs. DWC technology is well-suited for both revamp and grassroots applications in various hydrocarbon separation services. DWC revamp scenarios may include: Converting a two-column sequence into a single-column DWC. Modifying an existing two-product column for an additional side-draw product. prominent separation technologies in the refining and petrochemical industries. Installing a DWC to improve fractionation quality in an existing three-product conventional column. Distillation schemes and DWC The traditional approach for separating ternary components involves a direct train (see Figure 1a ) or an indirect train (see Figure 1b ), where components are separated sequentially in a series of columns. Although effective in separating three or more components, these schemes are energy-inefficient due to the inherent remixing phenomenon. Additionally, typically require higher capital investment and more equipment. A thermally coupled design, such as the Petlyuk column (see Figure 1c ), provides improved energy efficiency compared to a conventional sequential column design while
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Figure 1a Direct train; 1b Indirect train; 1c Petlyuk column
achieving the same level of fractionation. In this configuration, the vapour and liquid streams leaving the first column are directly connected to the second column. This eliminates the
Refining India
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