MECHANICAL OPERATIONS QUIZ

Maximum size reduction in a fluid energy mill is achieved by

Interparticle attrition

Impact

Compression

Cutting

TRUE ANSWER : ?
YOUR ANSWER : ?

In the cyclone separator used for separation of dust from dust laden gas, the gas

Is admitted tangentially at high velocity

Enters the cyclone from the top

Both B and C

Develops a helical motion inside the chamber

TRUE ANSWER : ?
YOUR ANSWER : ?

Fluid energy mill comes in the category of

Crusher

Grinder

Cutter

Ultrafine grinder

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YOUR ANSWER : ?

For a turbine agitated and baffled tank, operating at low Reynold's number (based on impeller diameter), the power number (Np) varies with NRe as

Np ∝ NRe

Np ∝ 1/NRe

Np → constant

Np ∝ √NRe

TRUE ANSWER : ?
YOUR ANSWER : ?

A fluid energy mill is used for

Crushing

Cutting

Ultra grinding

Grinding

TRUE ANSWER : ?
YOUR ANSWER : ?

Close circuit grinding by a ball mill with air sweeping employs a

Classifier

Cyclone separator between mill & classifier

Both A & B

Neither A nor B

TRUE ANSWER : ?
YOUR ANSWER : ?

For removal of very small amounts of precipitate from large volume of water, the most suitable filter is the __________ filter.

Sand

Shell & leaf

Plate & frame

Rotary vacuum

TRUE ANSWER : ?
YOUR ANSWER : ?

Which of the following is not used as a filter medium in case of corrosive liquids?

Metal cloth of monel or stainless steel

Glass cloth

Nylon

Cotton fabric

TRUE ANSWER : ?
YOUR ANSWER : ?

Pick out the wrong statement pertaining to the roll crushers.

Both the rolls run necessarily at the same speed

For hard material's crushing, the reduction ratio should not exceed 4

Reduction ratio and differential roll speed affect production rate & energy consumed per unit of surface produced

Maximum feed size determines the required roll diameter

TRUE ANSWER : ?
YOUR ANSWER : ?

The specific surface of spherical particles is given by (where D and ρ are diameter and density of particle).

4/D.p

6/D.p

12/D.p

2/D.p

TRUE ANSWER : ?
YOUR ANSWER : ?