Effects of reboiler and condenser behaviors during overfilling of debutanizer column to PRV sizing

One of the most important operations during chemical and petrochemical processing was separation of liquids mixture into two or more components. This separation irregularly referred.to fractionating column, fractional distillation or distillation column due to its ability to separate the mixture into its component part or fraction based on its differences in volatilities. Debutanizer column (de-butaniser) is part of the fractional distillation family. The target fraction unit for debutanizer column is to fractionation and produce butane products. Existence of overfilling during the process can affects plant performance, plant cost and environment. Overfilling or flooding is a condition where vapor flow is higher compare to liquid flow, thus liquid is unable to come down through down comer and happen if there any failure at the down comer of distillation column, where this event can cause overpressure in distillation column. Failure of down comer stream can occur when control valve (valve damage) at the bottom stream which is can’t detect by control system of debutanizer column. Therefore, this work studies the effect of overfilling at hermosyphon reboiler and overhead condenser and its impact to PRV sizing for the debutanizer column profile which are phase flow condition,
temperature and flowrate from its feed stream column and its importance for pressure relief valve sizing. The work was simulated using Aspen HYSYS simulation and manual calculation under four different debutanizer column profiles. From the result, it is a confirmed that each PRV has different in size, the mass flux are important subject in order to control PRV sizing.