Abstract

Capacity augmentation by structured packing revamp in stabilizer unit

Author(s): Mohammad Mehdi Zarei, Mortaza Zivdar

At the present investigation, capacity increase of stabilizer unit including two columns, debutanizer and splitter column, which are actually used in Shiraz Refinery Complex, has been studied. From distillation tower with structure of valve tray column, upstreamflowgoes into stabilizer unit.After passing through the debutanizer and splitter units respectively light straight run gasoline (LSRG) and Heavy straight run gasoline (HSRG) are produced. Regarding quality of final products and also capacity of explained unit, revamping has been applied in process simulation. Results of simulation illustrated that revamping of structured packing in the mentioned unit is an effective method to augmentation capacity. Debutanizer and splitter units have been particularly simulated with respect to intake and outlet flow rates, flooding, operational pressure and temperature. The simulation resultswere definitely compatiblewith operational data and experimental analysis. Using MELLAPAK 250X, as used structured packing in revamping process, led to decrease in pressure drop from 196 to 23 mBar. In addition, Sichlmair model has been proposed as the most feasible pressure drop estimator.With regard to packed tower flooding, 31 % capacity increase in feed flow rate and better quality productions have been definitively reported with total mean square error, about 4 percent.