Process Equipment Design -I — Winter 2021

Discuss the criteria for fluid allocation in shell & tube heat exchanger.

Discuss the five standard locations of pressure taps in orifice meter.

Hexane at 37.8 °Cis pumped through the system at a rate of 9.09 m3/hr. The tank is at atmospheric pressure. Pressure at the end of discharge line is 345 kPa g. The discharge head is 3.05 m and the suction lift is 1.22 m above the level of liquid in the tank. The friction loss in suction line is 3.45 kPa and that in the discharge line is 37.9 kPa. The mechanical efficiency of the pump is 0.6. The density of hexane is 659 kg/m3 and its vapor pressure at 37.8 °Cis 33.71 kPa. Calculate (i) (NPSH)Aand (ii) Power required by the centrifugal pump.

Define: Weeping, Entrainment, Coning in distillation column

Define NPSH and write short note with giving importance for pump design.

Discuss about the Liquid distributors, Liquid redistributors, Packing support and Hold-down plate for packed tower type absorber.

Discuss the criteria of selection among the different types of the equipment used as absorbers or scrubbers.

What is jet flooding and downcomer flooding?

Briefly explain the desired solvent properties required for choice of solvent in liquid-liquid extraction.

In vertical thermosyphon reboiler recirculation ratio is fixed by trial and error method. Discuss how to find or fix the recirculation ratio in the following conditions:

ΔPav ≈ ΔPt (ii) ΔPav > ΔPt (iii)ΔPav < ΔPt

List important industrial application of liquid-liquid extraction

State the advantages and disadvantages of vacuum distillation.

Discuss the criteria of selection among the different types of trays used in tray tower.

What is the function of downcomer? Discuss the different types of downcomers used in distillation column.

Explain Tinker’s flow model with a neat diagram.

Asaturated liquid, consisting of phenol and cresol with some xylenols, is fractioned to give a top product of 95.3 mole % phenol. Metacresol is heavy1 key and phenol is light key component. Total condenser is used. The composition of the top product and of the phenol in the bottom is given.

Complete the material balance over the still for a feed rate of 100 kmol/h and (ii) Calculate the minimum reflux ratio by Underwood’s method. Top Bottom Feed, Component α av product, product, mole % mole % mole % Phenol 1.98 35 95.30 5.24 o-Cresol 1.59 15 4.55 ? m-Cresol 1.00 30 0.15 ? Xylenols 0.59 20 -- ?

How baffle cut and baffle spacing affect tube outside heat transfer coefficient?

Discuss in brief Random and Regular packing.

Explain Air Cooled Heat Exchanger in brief.

Discuss advantage and disadvantage of plate heat exchanger over shell and tube heat exchanger.

Discuss stepwise design procedure for horizontal and vertical gravity decanter.

Why expansion joint is provided in fixed tube sheet heat exchanger?

Write short note on selection of key components in multicomponent distillation

Discuss in detail about the various criteria of selection between horizontal and vertical condenser.