A. Propellers
B. Turbine agitators
C. Multiple blade paddles
D. None of these
Related Mcqs:
- 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_________________?
A. Np ∝ NRe
B. Np ∝ √NRe
C. Np → constant
D. Np ∝ 1/NRe - A 30% (by volume) suspension of spherical sand particles in a viscous oil has a hindered settling velocity of 4.44 μm/s. If the Richardson Zaki hindered settling index is 4.5, then the terminal velocity of a sand grain is_________________?
A. 0.90 μm/s
B. 1 μm/s
C. 22.1 μm/s
D. 0.02 μm/s - Which of the following agitators having a large blade area, rotating at slow speed is used for mixing high viscosity liquids (> 50000 centipoise) ?
A. Propeller
B. Helical screw
C. Flat blade turbine
D. Curved blade turbine - During agitation of liquids, the_________________?
A. Froude number is independent for the curves between power number and Reynolds number in
baffled system
B. Power number becomes independent of impellers Reynolds number at high Reynolds number,
but is dependent on the geometry of the impeller
C. Froude number is used to account for the effect of surface (e.g., the centre vortex) on the
power number
D. All A., B. and C. - The process by which fine solids is removed from liquids is termed as _____________________?
A. Decantation
B. Flocculation
C. Sedimentation
D. Classification - During agitation of liquids, power consumption during laminar flow is not proportional to the ________________?
A. Density of the liquid
B. Viscosity of the liquid
C. Cube of impeller diameters
D. Square of rotational speed - Which of the following may prove unsuitable for filtering volatile liquids ?
A. Pressure filter
B. Gravity filter
C. Centrifugal filter
D. Vacuum filter - Which of the following is not used as a filter medium in case of corrosive liquids?
A. Nylon
B. Glass cloth
C. Metal cloth of monel or stainless steel
D. Cotton fabric - Which of the following is not accomplished by agitation of liquids in agitators ?
A. Dispersing gas in liquid
B. Blending of immiscible liquids
C. Dispersing immiscible liquid in form of emulsion
D. Suspending solid particles - Pebble mills are tumbling mills widely used for grinding in the manufacture of paints & pigments and cosmetic industries, where iron contamination in the product is highly objectionable. Pebbles used in pebble mill are made of__________________?
A. Bronze
B. Stainless steel
C. Flint or porcelain
D. Concrete
