Q.1
The ratio of the area of openings in one screen (Taylor series) to that of the openings in the next smaller screen is
Q.2
Crushing of mineral particles is accomplished in a 'cage mill', when one or more alloy steel bars are revolved in opposite directions. It is a type of __________ mill.
Q.3
A fluid energy mill is used for
Q.4
A __________ employs a set of screen across a flow channel for the separation of dirt/rust from a flowing liquid stream.
Q.5
Which of the following can be most effectively used for clarification of lube oil and printing ink?
Q.6
Capacity (in tons/hr) of jaw/gyratory crusher is equal to (where, L = length of the receiving opening, cm S = greater width of the discharge opening, cm)
Q.7
Size measurement of ultrafine particles can be best expressed in terms of
Q.8
Rittinger number which designates the new surface prduced per unit of mechanical energy absorbed by the material being crushed, depends on the
Q.9
The controlling resistance in a rotary drum vacuum filter is the __________ resistance.
Q.10
Shape factor for a cylinder whose length equals its diameter is
Q.11
The most efficient equipment for the removal of sub-micronic dust particles from blast furnace gas is the
Q.12
The specific cake resistance for compressible sludges is a function of the pressure drop
Q.13
__________ mixer is used for devulcanisation of rubber scrap & making water dispersion & rubber solution.
Q.14
The process opposite to 'dispersion' is termed as the
Q.15
Size reduction does not occur due to compression in case of
Q.16
Percentage of drum submerged in the slurry in case of rotary drum filter is
Q.17
In froth floatation, chemical agent added to cause air adherence is called
Q.18
In case of a plate and frame filter press, filtrate flow through the cake follows __________ flow.
Q.19
Screen capacity is not a function of
Q.20
Which of the following gives the work required for size reduction of coal to -200 mesh in a ball mill most accurately ?
Q.21
Traces of solids are removed from, liquid in a
Q.22
Pick out the correct statement.
Q.23
During filtration operation, the filtrate encounters the resistance of the
Q.24
__________ balls capable of grinding the feed in a ball mill gives the maximum efficiency.
Q.25
Mixing mechanism employed in a pan mixer is by
Q.26
During washing of filter at the end of constant pressure filtration, the rate of washing equals the rate of filtration
Q.27
In constant pressure filtration,
Q.28
Size reduction of the __________ can be suitably done by ball mills, crushing rolls and rod mills.
Q.29
In a mixer, the quantity, (v. L/D) is termed as __________ number(where, v = longitudinal velocity of material, L = length of the mixer, D = diffusivity in axial mixing).
Q.30
In case of a hammer crusher, the
Q.31
__________ mills are termed as disintegrators.
Q.32
Which of the following is not categorised as a "mechanical operation"?
Q.33
Sphericity of a cubical particle, when its equivalent diameter is taken as the height of the cube, is
Q.34
Optimum ratio of operating speed to critical speed of a trommel is
Q.35
Energy requirement (per unit mass of material crushed/ground) is highest for
Q.36
Particle size range in which dust catcher (gravity settling chamber) works most effectively and efficiently is __________ microns.
Q.37
Which of the following relationships between co-efficinet of friction (μ) between rock & roll and a (half of the angle of nip) of the particle to be crushed is correct ?
Q.38
In coal washeries, three products namely the valuable product (i.e. clean/washed coal), discarded product (i.e. mineral matter) and an additional concentrated product called __________ is produced.
Q.39
Weber number is significant and is concerned with the
Q.40
Handling of ashes and similar materials can be done best by a __________ conveyor.
Q.41
Bond crushing law
Q.42
Which of the following crushers can be considered as a combination of a jaw crusher and a roller crusher?
Q.43
Float and sink test determines the possibility of cleaning of coal by a process based on the
Q.44
Which of the following represents the plot of filtrate volume versus time for constant pressure filtration?
Q.45
Which of the following is a batch sedimentation equipment?
Q.46
The most suitable filter for the removal of very small amount of precipitate from very large volumes of water is the __________ filter.
Q.47
Ball mills and tube mills with flint or porcelain balls are used for size reduction of
Q.48
With increase in the pressure drop across the cake, the specific cake resistance for the compressible sludge
Q.49
Chance process is used for the
Q.50
Compressibility co-efficient for an absolutely compressible cake is
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