(Solved): Q2. A crude oil distillation column operates with top temperature of \( 108^{\circ} \mathrm{C} \) a ...

Q2. A crude oil distillation column operates with top temperature of \( 108^{\circ} \mathrm{C} \) and pressure of \( 1.15 \mathrm{~kg} / \mathrm{cm}^{2}(\mathrm{~g}) \). The column operates with reflux ratio of 3.1. The gas make from the overhead reflux drum is \( 75 \mathrm{~kg} / \mathrm{hr} \) and this stream can be considered as ethane \( (\mathrm{MW}=30) \). Unstabilised naphtha feed to the naphtha stabilizer column from the reflux drum is \( 66 \mathrm{mt} \)./hr. This stream has average \( \mathrm{MW} \) of 70 . Total stripping steam used in the column is \( 6250 \mathrm{~kg} / \mathrm{hr} \). The water slippage with the crude feed, due to the inefficiency of the desalter, is \( 0.05 \mathrm{~kg} / \mathrm{mt} \) of crude. Will any moisture condense on the top tray? Vapour pressure (Pw) of water in \( \mathrm{mmHg} \), corresponding to temperature \( \mathrm{T}^{\circ} \mathrm{C} \) is given by \( \log _{10}(P w)-8.14019-1810.94 /(T+244.485) \). [10 marks]