Ideally the drying should be done to a level of
(a) EMC (b) CMC (c) FMC (d) Zero moisture content
(1M)
ii) Freeze drying works on the principle of
(a) Evaporation of water
(b) Sublimation of water from ice phase to gas phase
(c) Liquefaction of ice to water
(d) Heating at the freezing temperature of water
(1M)
iii) The most efficient heat exchange between the particles and flowing air occurs
in the
(a) Tray dryer (b) Spray dryer
(c) Fluidized bed dryer (d) Rotary dryer
(1M)
iv) Reynold’s number (Re) for streamline flow of a fluid is
(a) <0.2 (b) >0.2 (c) <0.8 (d) >0.8
(1M)
v) Following is not the mechanism of size reduction
(a) Impact and attrition (b) Cutting
(c) Bruising (d) Elutriation
(1M)
vi) For effective operation of ball mill the ball charge
(% volume of mill filled by the balls) should be
(a) 60–70% (b) 30–50% (c) <30% (d) >50%
(1M)
vii) Critical speed of the ball mill is the speed at which
(a) Balls begin to centrifuge with the mill
(b) Balls cascade over one another
(c) Balls are carried up the sides and fall freely onto material
(d) Balls start tumbling
(1M)
viii) Total 100 squares in a 1 inch2 area is termed
(a) 100 mesh sieve (b) 10 mesh sieve
(c) 20 mesh sieve (d) 25 mesh sieve
(1M)
ix) Filter aids may be applied by
(a) Precoating technique (b) Body-mix technique
(c) Both (d) None
(1M)
x) Integrity tests are intended for following filters:
(a) Leaf filters (b) Drum filters
(c) Membrane filters (d) Edge filters
(1M)
xi) The equation describing the factors affecting the rate of filtration is
(a) Darcy’s equation (b) Dalton’s equation
(c) Stokes’ equation (d) None
(1M)
xii) Hammer mill works by following principle:
(a) Impact (b) Attrition (c) Compression (d) Non