Partech

Question 1

Increasing the capacity of screen causes ____

Answer 1

decreases the screen effectiveness

Question 2

Equation for Screen efficiency is

Answer 2

recovery x rejection

Question 3

The material passing one screening surface and retained on a subsequent surface is called

Answer 3

intermediate material

Question 4

Size measurement of ultrafine particles can be best expressed in terms of

Answer 4

surface area/ unit mass

Question 5

The hardness of a mineral is a criterion of its resistance to crushing.
Which of the following is an example of a hard material?

Answer 5

sapphire

Question 6

Mesh indicates the number of holes per

Answer 6

Linear inch

Question 7

Describe:
Tyler Standard Sieve Series
US Standard Sieve Series
International Test Sieve Series

Answer 7

Tyler Standard Sieve Series: consecutive mesh have sqrt(2) ratio
US Standard Sieve Series: consecutive mesh have fourth root of 2 ratio
International Test Sieve Series: similar to both, but have different wire gauges

Question 8

The standard equipment recommended for automatically carrying out sieve test procedures with accuracy and dependability.

Answer 8

Ro tap shaker (read Screening)

Question 9

A major expense in crushing and grinding of feed material

Answer 9

Cost of power

Question 10

For the preliminary breaking of hard rock, we use a ____

Answer 10

Gyratory crusher

Question 11

Size reduction mechanism used in jaw crushers is ____

Answer 11

Compression

Question 12

The main size reduction operation in ultrafine grinders is

Answer 12

Attrition

Question 13

Explain Taggart’s Rule

Answer 13

T= 0.6 * L * S
T: short ton/hr
L: length feed opening, in
S: greatest with of opening, in

if T/S^2 > 0.155: Use Gyratory crusher
if T/S^2 < 0.155: Use Jaw crusher

Question 14

Size Reduction Mechanism:
Coarse
Fine
Ultrafine

Answer 14

Coarse: Compression
Fine: Impact
Ultrafine: Attrition

Question 15

As the product becomes finer, the energy required for grinding

Answer 15

increases

Question 16

To get a fine talc powder from its granules, the equipment used is

Answer 16

Ball mill

Question 17

Maximum size reduction in a ball mill is done by ______

Answer 17

Impact

Question 18

The operating speed of a ball mill should be __________ the critical speed.

Answer 18

Less than

Question 19

The operation by which solids are separated from liquids due to difference in the respective densities is ______

Answer 19

sedimentation

Question 20

Forces acting on a particle settling in fluid are ___ (multiple answers)

Answer 20

gravitational or centrifugal, buoyant and drag forces

Question 21

Drag is defined as the force exerted by the ____

Answer 21

fluid on the solid in a direction opposite to flow

Question 22

Stoke’s law is valid when the particle Reynolds number is _____

Answer 22

Re,p <1

Question 23

In hindered settling, the particles are
A. Placed farther from the wall
B. Not affected by other particles and the wall
C. Near each other
D. None of these

Answer 23

Near each other

Question 24

Drag co-efficient in hindered settling is __________ that in free settling.
A. Less than
B. Equal to
C. Not necessarily greater than
D. Always greater than

Answer 24

Always greater than

Question 25

Filter aid is used to ____ A. Increase the rate of filtration B. Decrease the pressure drop C. Increase the porosity of the cake D. Act as a support base for the septum

Answer 25

Increase the porosity of the cake

Question 26

During the washing of cake ____ A. All the resistances are constant B. Filter medium resistance increases C. Filter medium resistance decreases D. Cake resistance decreases

Answer 26

All the resistances are constant

Question 27

The porosity of a compressible cake is _____ a. minimum at the filter medium b. minimum at the upstream face c. maximum at the filter medium d. same throughout the thickness

Answer 27

Minimum at the filter medium

Question 28

The terminal velocity of a small sphere settling in a viscous fluid varies as the ______ a. first power of its diameter b. inverse of the fluid viscosity c. inverse square of the diameter d. square of the difference in specific weights of solid and fluid

Answer 28

Inverse of the fluid viscosity

Question 29

Buoyant force _____ a. for non-symmetrical bodies is not vertical b. depends on the depth of the submergence of the floating body c. depends on the weight of the floating body d. none of these

Answer 29

Depends on the weight of the floating body

Question 30

Terminal velocity is ______ a. constant velocity with no acceleration b. a fluctuating velocity c. attained after moving one-half of total distance d. none of these

Answer 30

A constant velocity with no acceleration

Question 31

Which of the following may prove unsuitable for filtering volatile liquids? a. pressure filter b. centrifugal filter c. gravity filter d. vacuum filter

Answer 31

Vacuum filter

Question 32

In washing type plate and frame filter press the ratio of washing rate to the final filtrate rate is ____ a. 4 b. 1 c. ¼ d. ½

Answer 32

¼

Question 33

Moore filter is a __________ . A. Leaf filter B. Press filter C. Rotary filter D. Sand filter

Answer 33

Leaf filter

Question 34

Diatomaceous earth is a/an ______ A. Explosive B. Filter aid C. Filter medium D. Catalyst

Answer 34

Filter aid

Question 35

Particle diameter in size 50% passes through equipment (undersize) and 50% discharged through equipment (oversize)

Answer 35

Cutpoint Diameter Critical Diameter

Question 36

If the radius of a basket centrifuge is halved and the rpm is doubled, then _____ a. linear speed of the basket is doubled b. linear speed of the basket is halved c. centrifugal force is doubled d. capacity of centrifuge is increased

Answer 36

Centrifugal force is doubled

Question 37

For separation of sugar solution from settled out mud we use _____

Answer 37

Centrifugal filter

Question 38

Which is the driving force behind free falling body?

Answer 38

gravitational force

Question 39

A flotation modifier which assists in selectivity (sharpness of separation) or stop unwanted minerals from floating is a/an _____

Answer 39

depressants

Question 40

Froth floatation is the most suitable for treating ____

Answer 40

Sulphide ores

Question 41

In Froth Flotation, chemical agent added to cause air adherence is called ____

Answer 41

collector

Question 42

Pine oil used in froth floatation technique acts as a/an _____

Answer 42

Frother

Question 43

It is the separation of fluid-solid mixture involving the passage of most of the fluid through a porous membrane which returns most of the solid particles contained in the mixture

Answer 43

filtration

Question 44

Which of the following types of filter are made to operate to continuously? a. rotary drum b. gravity c. filter press d. leaf filter

Answer 44

rotary drum

Question 45

A major expense in crushing and grinding of feed material

Question 46

Moh's Scale if Hardness

Answer 46

Trading Game Coming FAF QTCD *Soft: 1.Talc 2.Gypsum 3.Calcite *Intermediate: 4.Fluorite 5.Apatite 6.Feldspar *Hard 7.Quartz 8.Topaz 9.Corundum 10.Diamond

Question 47

Stages of Size Reduction Equipment

Answer 47

*Coarse Gyratory Crusher Jaw Crusher Hammer Mill *Intermediate Cone crusher Crushing rolls *Fine Ball Mills Rod Mills

Question 48

Parallel metal bars in an inclined stationary frame

Answer 48

Grizzly Screens

Question 49

Screen frequency controlled by electromagnetic vibrator mounter above and directly to screening surface

Answer 49

Vibrating screen

Question 50

Composes of rotating perforated drum separating particles from smallest to biggest

Answer 50

Reciprocating Screens