Steady state simulation model of vacuum distillation tower for operational use.

The objective of this thesis is to develop a simulation model of vacuum distillation tower (DA-73001) to monitor the routine activities. Furthermore, the simulation model must illustrate the effect of liquid entrainment and buffer-cut wash bed performance on distillation efficiency. Vacuum distillation column internals, fouling and coking mechanism, VDU fouling and its mitigation have been discussed in the literature part. The formation of coke by decomposition of compounds at high heat flux regions in the furnace can be avoided by the increasing the steam rate in the furnace tube. The minimum liquid entrainment and improved vapor distribution to the wash bed can be achieved by installing a suitable feed inlet device in the flash zone. The wash oil reflux must be maintained above the minimum wetting rate of the packing to prevent wash beds from coking. The simulation model facilitates in the operations to ensure the operational parameter and product quality from the column has been maintained. To make the model convenient to be applicable in the operations, model user-interface on Microsoft Excel has been developed to make it accessible for the users unacquainted with the simulator interface