In case of grinding in a ball mill (A) Wet grinding achieves a finer product size than dry grinding (B) Its capacity decreases with increasing fineness of the products (C) Grinding cost and power requirement increases with increasing fineness of the products (D) All (A), (B) and (C)

In case of grinding in a ball mill
(A) Wet grinding achieves a finer product size than dry grinding
(B) Its capacity decreases with increasing fineness of the products
(C) Grinding cost and power requirement increases with increasing fineness
of the products
(D) All (A), (B) and (C)
by

1 Answer

Answer :

(D) All (A), (B) and (C)
by

Related questions

Wet grinding in a revolving mill __________ as compared to dry grinding. (A) Gives less wear on chamber walls (B) Requires more energy (C) Increases capacity (D) Complicates handling of the product

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Last Answer : (C) Increases capacity

In case of a revolving mill, wet grinding compared to dry grinding (A) Requires more energy (B) Has less capacity (C) Complicates handling & classification of the product (D) None of these

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As the product becomes finer, the energy required for grinding (A) Decreases (B) Increases (C) Is same as for coarser grinding (D) Is 1.5 times that for coarser grinding

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Last Answer : (B) Increases

Actual operating speed of a ball mill may vary from 65 to 80% of the critical speed. Which of the following duties would require the ball mill to be operated at maximum percentage of critical speed? (A) Wet grinding in low viscous suspension (B) Wet grinding in high viscous suspension (C) Dry grinding of large particles (upto 1.25 cms) (D) Dry grinding of large particles in un-baffed mills

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A tube mill as compared to a ball mill (A) Employs smaller balls (B) Gives finer size reduction but consumes more power (C) Has larger length/diameter ratio (>2 as compared to 1 for ball mill) (D) All (A), (B) and (C)

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Tube mill compared to ball mill (A) Produces finer products (B) Is long in comparison with its diameter (C) Uses smaller balls (D) All (A), (B) & (C)

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Last Answer : (D) All (A), (B) & (C)

The main differentiation factor between tube mill and ball mill is the (A) Length to diameter ratio (B) Size of the grinding media (C) Final product size (D) Operating speed

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Use of grinding aids results in the (A) Enhanced production rate (B) Finer products (C) Both (A) & (B) (D) Neither (A) nor (B)

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Last Answer : (A) Buhrstone mill

__________ balls capable of grinding the feed in a ball mill gives the maximum efficiency. (A) Cast iron (B) Minimum size (C) Maximum size (D) Elliptical

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Work index is the gross energy (kWh/tonne of feed) necessary to reduce a very large feed to such a size that 80% of product particles will pass through a 0.1 mm screen. The value of work index determined for wet grinding should be multiplied with __________ to get the same for dry grinding. (A) 1.0 (B) 0.5 (C) 1.34 (D) 4.34

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For grinding of softer materials, the grinding wheel should have __________ grain size. (A) Finer (B) Coarser (C) Medium (D) Any type of

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Production rate __________ with increased fineness, with a given energy input to the size reduction machine. (A) Decreases (B) Increases (C) Remains unchanged (D) May increase or decrease; depends on the machine

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A pebble mill (A) Is a ball mill (B) Employs flints or ceramic pebbles as the grinding medium (C) Is a tube mill lined with ceramic or other non-metallic liner (D) Both (B) and (C)

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Ball mill is used for (A) Crushing (B) Coarse grinding (C) Fine grinding (D) Attrition

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Grinding efficiency of a ball mill is of the order of __________ percent. (A) 1-5 (B) 40-50 (C) 75-80 (D) 90-95

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Explain the procedure to determine fineness of cement by dry sieving method. State its IS requirement.

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In ball mill operation, the feed size (Df in meters) and the ball diameter (Db in metres) are related as (where, K = grindability constant (varying from 0.9 to 1.4 in increasing order of hardness)) (A) Db 2 = K.Df (B) Db = K.Df (C) Db 3 = K.Df (D) Db 2 = K.Df

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The capillary rise of water (A) Depends upon the force responsible (B) Increases as the size of the soil particles increases (C) Decreases as the size of the soil particles decreases (D) Is less in wet soil than in dry soil

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Which of the following grinding mills has the horizontally arranged rods as the grinding elements thereby delivering more uniform granular products with minimum fines? (A) Compartment mill (B) Rod mill (C) Pebble mill (D) Tube mill

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