Free Chemical Process Principles MCQs with Answers

• A. Remains unchanged
• B. Increases
• C. Decreases
• D. Decreases exponentially

Explanation: Increasing screen capacity generally increases the feed loading per unit screening area and reduces the time available for particles to…

• A. Open sand
• B. Plate and frame
• C. Vacuum leaf
• D. Sparkler

Explanation: Open sand filters are commonly used for large-volume water clarification, including water treatment in paper mills.

• A. Specific surface ratio
• B. Shape factor
• C. Sauter diameter
• D. Surface area per unit mass

Explanation: Sphericity compares the surface area of a volume-equivalent sphere with the actual particle surface area, so its reciprocal is a shape…

• A. Capacity and effectiveness of the screen is increased
• B. Screening becomes progressively easier
• C. Screening becomes progressively more difficult
• D. None of these

Explanation: Very small particles are difficult to screen because they tend to agglomerate, pass slowly through the apertures, and blind the screen.

• A. Jaw crusher
• B. Gyratory crusher
• C. Cone crusher
• D. Roll crusher

Explanation: Roll crushers generally operate with a relatively small size-reduction ratio, commonly about 3 to 4, whereas jaw, cone, and gyratory…

• A. Surface area per unit mass
• B. Screen size
• C. Micron
• D. Centimetre

Explanation: Ultrafine particles are too small for convenient measurement by ordinary screens, centimetres, or even practical screen-size descriptions.

• A. State or manner of application of the crushing force
• B. All A., B. and C.
• C. Elastic constant of the material
• D. Ultimate strength of the material

Explanation: The Rittinger number is not a universal constant; it depends on the material properties and on how the crushing force is applied.

• A. Filter medium
• B. All A., B. and C.
• C. Channel carrying the slurry to the upstream side of the cake and filtrate away from the filter
• D. medium
• E. Cake

Explanation: Filtrate flow is opposed by resistance from the filter medium, the deposited cake, and the connected flow passages carrying slurry and…

• A. Pug mill
• B. Pan mixer
• C. Banbury mixer
• D. Charge can mixer

Explanation: A Banbury mixer is an intensive internal mixer designed for compounding rubber and plastic materials, using strong shear and kneading…

• A. With minimum possible small balls
• B. At a speed more than the critical speed
• C. At a speed equal to the critical speed
• D. At a speed less than the critical speed

Explanation: Above the critical speed, centrifugal force holds the balls against the mill wall and prevents effective impact and cascading.

• A. Poor grindability
• B. Easier grindability
• C. High power consumption in grinding
• D. None of these

Explanation: Rittinger's number measures new surface produced per unit energy, so a larger value means more surface is obtained for the same energy and…

• A. Hammer crusher
• B. Roll crusher
• C. Ball mill
• D. Gyratory crusher

Explanation: Carbon black requires fine pulverisation, for which a ball mill is suitable because repeated impact and attrition reduce the material to…

• A. Sand bed filter
• B. Plate and frame filter press
• C. Batch basket centrifuge
• D. Vacuum filter

Explanation: A vacuum filter is suitable because it can be constructed with corrosion-resistant filter materials and handles abrasive solids without…

• A. Independent of ΔP
• B. ∝ 1/ ΔP
• C. ∝ √ΔP
• D. ∝ ΔP

Explanation: For an incompressible cake, the cake structure does not change as pressure rises, so its specific resistance remains constant and is…

• A. Cake thickness
• B. Characteristics of the feed slurry
• C. Both A. & B.
• D. Neither A. nor B.

Explanation: Rotary drum vacuum-filter capacity depends on cake thickness, which controls the filtration resistance, and on feed-slurry characteristics…

• A. to the square root of the volume to surface ratio of the product
• B. Is less realistic in estimating the power requirements of commercial crushers
• C. States that the work required to form particle of any size from very large feed is proportional
• D. Calls for relatively less energy for the smaller product particles, than does the Rittinger law
• E. States that the work required for the crushing is proportional to the new surface created

Explanation: Compared with Rittinger's law, Bond's law predicts relatively less energy for producing very small particles because its energy…

• A. 6.V/D.S
• B. V/6D.S
• C. D.S/V
• D. V/D.S

Explanation: Sphericity is the surface area of a sphere having the same volume divided by the actual particle surface area.

• A. Compressible cakes and laminar
• B. Incompressible cake and laminar
• C. Compressible cake and turbulent
• D. Incompressible cake and turbulent

Explanation: For laminar filtration through an incompressible cake, resistance increases linearly with cake thickness and hence with filtrate volume…

• A. 1.0
• B. 0.5
• C. 1.34
• D. 4.34

Explanation: Dry grinding generally requires more energy than wet grinding because liquid reduces agglomeration and improves transport of particles.

• A. Apron conveyor
• B. Belt conveyor
• C. Bucket elevator
• D. Screw conveyor

Explanation: A screw conveyor can move cohesive, semi-solid, and pasty materials because its rotating screw positively pushes the material forward.