Chemical Engineering Archives

4331. In a shell and tube heat exchanger, the ‘tube pitch’ is defined as the

O.D. of the tube for square pitch.

shortest distance between two adj acent tube holes.

shortest centre to centre distance between adjacent tubes.

none of these.

✅ The correct answer is option C.

4332. Which of the following types of reactors is the safest from operation point of view ?

A vapor phase reactor.

Pot type reactor.

A liquid phase reactor.

A liquid phase catalytic reactor.

✅ The correct answer is option A.

4333. “A claming section” before the liquid flows into the downcomer is privided to

permit release of entrained vapour in the liquid.

reduce the discharge fluctuation.

ensure better vapour-liquid contact.

cool the liquid before it flows down.

✅ The correct answer is option A.

4334. Pick out the wrong statement pertaining to the comparative evaluation of performance of the packed tower and the plate tower.

Plate tower is perferred, if interstage cooling is required to remove heats of reaction or solution.

Plate tower is preferred over packed tower, if the operation involves liquids containing dispersed solids.

The total weight of a dry plate tower is usually much more than that of a dry packed tower designed for the same duty.

In operations involving large temperature changes. (e.g. distillation), plate towers are preferred over packed towers as the packing may be crushed due to large temperature changes.

✅ The correct answer is option C.

4335. Liquid redistribution should be done in a packed tower packed with raschig rings every 6 metres or __________ times the column diameter, whichever is lower.

2.5-3.0

5-7.5

10-12.5

15-20

✅ The correct answer is option A.

4336. In a multiple effect evaporator system having ‘n’ effects, the amount of water evaporated per unit surface area in approximately equal to __________ times that in a single effect.

n’th

(1/n)th

0.5 nth

1.5 nth

✅ The correct answer is option B.

4337. With increase in pressure drop (for a given particle size), the dust collection efficiency of a cyclone separator will

increase

decrease

remain unaffected

increase or decrease depending on the nature of the dust.

✅ The correct answer is option A.

4338. Reflux ratio variation in a distillation column is between

zero and infinity

zero and one

minimum and infinity

none of these

✅ The correct answer is option C.

4339. The shell side pressure drop in a shell and tube heat exchanger is maximum for __________ baffle.

disk and ring

segmental

orifice

independent of the type of

✅ The correct answer is option C.

4340. With increase in gas flow rate to fabric surface area ratio (Nm3/hr/m2 fabric surface area), the size & the cost of a bag filter

increases

decreases

remain unaffected

none of these

✅ The correct answer is option B.