UDEX Process Expansion

C&I’s process group established a design basis, provided numrerous PFDs, and conducted expansion studies on this multi-phase project. The initial scope of the work was confined to evaluations of the reformate splitter upstream of the UDEX unit, and both the solvent extraction section and product distillation sections of the UDEX unit. Persistent questioning by C&I about the quantity of light normal paraffins in the reformate splitter feed, led to including the Naphtha Splitter, upstream of the two catalytic reformers, in the study work.

Simulating the solvent section of the UDEX is not possible with conventional equilibrium data in commercial simulators. By partnering with an outside simulation firm, Virtual Material Group, C&I was able to rigorously model the entire solvent extraction section.

One of the areas the C&I process team questioned was the amount of light normal paraffins in the reformat, prompting additional study of the client’s naphtha splitter. By identifying the cause of the problem and correcting the process to reduce the amount of inerts entering the reformate splitter and UDEX unit, C&I significantly increased the refinery’s capacity for handling aromatics in the UDEX unit, as well as opening up available capacity in the catalytic reformers.

After the capacity study, the project continued into feasibility, and then detailed design.