Pick out the wrong statement pertaining to the design of the bubble cap tray of a distillation column to give stable operation and even vapour distribution.

Pick out the wrong statement pertaining to the use of valve tray, seive tray and bubble cap trays in continuous distillation column.

A

Bubble cap trays though most expensive are the best in situations, where low vapour rates is to be handled and a positive liquid seal is essential at all flow rates

B

Murphree efficiency of all the three trays are nearly equal, however the peak efficiency is generally higher for seive and valve trays than the bubble cap

C

Maintenance cost for valve and seive trays are comparatively more than bubble cap tray due to their relatively complicated construction features

D

Valve trays have the highest turn down ratio (i.e. the ratio of the highest to the lowest vapour flow rates) and thus provides the maximum flexible operating range

Bubble cap tray is the most commonly used tray in large distillation column, because

A

Of its flexibility and nearly constant efficiency under varying conditions of operation

B

It incurs less pressure drop as compared to any other try designed for the same duty

C

It eliminates the foaming and entrain-ment tendency during operation

D

None of these

Pick out the wrong statement about the design of seive plate column and the bubble cap column.

A

The downcomer design and the residence time in the downcomer is almost same for seive plate and bubble cap columns

B

Weir length for a bubble cap plate is the same as that for the seive plate

C

Weir height for a bubble cap plate column is the same as that for a seive plate column

D

Weir height in case of a bubble cap plate ranges from 50 to 150 mm and is higher than the seive plate

If altitude bubble is provided both on index frame as well as on telescope of a theodolite, then the instrument is levelled with reference toi) altitude bubble on index frameii) altitude bubble on index frame if it is to be used as a leveliii) altitude bubble on telescopeiv) altitude bubble on telescope if it is to be used as a level The correct answer is

A

only (i)

B

both (i) and (iv)

C

only (iii)

D

both (ii) and (iii)

If altitude bubble is provided both on index frame as well as on telescope of a theodolite, then the instrument is levelled with reference to
i) altitude bubble on index frame
ii) altitude bubble on index frame if it is to be used as a level
iii) altitude bubble on telescope
iv) altitude bubble on telescope if it is to be used as a level
The correct answer is

A

only (i)

B

both (i) and (iv)

C

only (iii)

D

both (ii) and (iii)

Consider the following Column A and Column B in which the names of microorganisms are given in Column A and the groups to which they belong are given in Column B: Column A Column B (a) Aspergillus (i) Algae (b) Lactobacillus (ii) Bacteria (c) Paramecium (iii) Fungi (d) Spirogyra (iv) Protozoa (v) Virus The correct match of the items of Column A with that of Column B is

A

a - iii, b - ii, c - iv, d - v

B

a - ii, b - iii, c - iv, d - i

C

a - iii, b - ii, c - iv, d - i

D

a - v, b - iii, c - ii, d - iv

Pick out the wrong statement pertaining to the design of the distillation column.

A

Generally, a skirt clerance of 0.5" to 1.5' is recommended to prevent plugging of the slots by residue build up

B

The purpose of the slot is to disperse the gas into the liquid in the form of small bubbles

C

If sufficient slot area is not provided, the gas may pass through the skirt clearance

D

None of these

For a given design of bubble cap, the number of bubble caps to be used per tray is set by the

A

Allowable gas velocity through the slots

B

Plate spacing

C

Diameter of the column

D

All of the above

Directios: In the question below three statements are given followed by four conclusions numbered I, II, III and IV. You have to take the given statements to be true even if they seem to be at variance with commonly known facts. Read all the conclusions and then decide which of the given conclusions logically follows from the given statements disregarding commonly known facts. Statements: Some Bat are Cap. Some Cap are Fan. No Fan is Bulb. Conclusions: I. Some Bat are Bulb. II. Some Cap is not Bulb. III. No Bat is Fan. IV. Some fan is cap

A

Only I follows

B

Only II follows

C

Only II and III follow

D

Only II and IV follows

E

Only III and IV follow

In case of bubble cap distillation column of diameter greater than 1.2 metres, the cap diameter is roughly about __________ cms.

A

10

B

20

C

30

D

35

Pick out the wrong statement pertaining to the design of the bubble cap tray of a distillation column to give stable operation and even vapour distribution.

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