Dynamic Simulation and Start-up Scenario a Pilot Distillation Column for Separating C6-C8 Hydrocarbons

Abstract

A pilot distillation column was fabricated for multipurpose functions, such as separation testing compared with a real plant distillation column, and sample preparation for other projects. The packing efficiency of this column was developed by changing the packing material. Packing efficiency is normally an important key index, especially after a revamp. Aspen Dynamic was used to generate the best procedure for the start-up operation, covering three variables: the distillate rate, the reflux rate and the bottom rate. The start-up procedure according to these three parameters was divided into six scenarios. In addition, the effect of reflux rate and feed location was the operating conditions, including temperature profile of the column, benzene concentration in the overhead stream, and liquid levels in the reflux drum and sump. The test run data matched well, with 0.6 Murphree efficiency. The optimal procedure for the start-up operation was found to be a distillate rate – bottom rate – reflux rate scenario, which took just 9 h to reach a steady state.