(31c) De-Bottleneck a PP Splitter with 4 Pass VGPlus Trays

Propylene is especially important for the production of the most varied industrial and consumer goods such as fittings and packaging material, as well as injection moldings of plastics and many others. It has been estimated that the growth rate of world Propylene consumption will substantially exceed the one of Ethylene consumption. Among all the emergent countries, Russia is one of the those in which the Propylene demand is expected to grow the most. In the last few years several Steam Crackers (Ethylene Plants) have been revamped in Russia to meet this request. Among all the distillation columns of an Ethylene Plant, the Propylene-Propane Splitter is surely the most critical tower. This is even more true in many Russian Steam Crackers where the PP-Splitters were equipped with "non conventional fractionation trays", providing with poor performances, therefore the recovery of Propylene was much lower than commonly achieved in modern Plants. In this paper a case story will be presented: the revamp of the PP-Splitter with the most updated mass transfer technology allowed for a significant boosting of the Propylene recovery. It will include a detailed discussion of the revamp approach: the process simulation, the selection of the most appropriate fractionation trays, the job implementation at site, and the achieved results.