The composition of the feed to a debutaniser is given below. Make a preliminarydesign for a column to recover 98 per cent of the n-butane overhead and 95 percent of the isopentane from the column base. The column will operate at 14bar and the feed will be at its boiling point. Use the short-cut methods andfollow the procedure set out below. Use the De Priester charts to determine therelative volatility. The liquid viscosity can be estimated using the data given inAppendix D

(a) Investigate the effect of reflux ratio on the number of theoretical stages

(b) Select the optimum reflux ratio.

(c) Determine the number of stages at this reflux ratio.

(d) Estimate the stage efficiency.

(e) Determine the number of real stages.

(f) Estimate the feed point.

(g) Estimate the column diameter.Feed composition:kg/hpropane C3 910isobutane i-C4 180n-butane n-C4 270isopentane i-C5 70normal pentane n-C5 90normal hexane n-C6 20