Mechanical Operations

Half the angle of nip, (α), for a roll crusher is given by (where, dr, dp and df are diameters of crushing rolls, feed particles and rolls gap respectively) ?

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Half the angle of nip, (α), for a roll crusher is given by (where, dr, dp and df are diameters of crushing rolls, feed particles and rolls gap respectively) ?

A. cos α = (dr + dp)/(dr + df)
B. cos α = (dr + df)/(dr + dp)
C. tan α = (dr + dp)/(dr + df)
D. sin α = (dr + dp)/(dr + df)

A suspension of glass beads in ethylene glycol has a hindered settling velocity of 1.7 mm/s, while the terminal settling velocity of a single glass bead in ethylene glycol is 17 mm/s. If the Richardson-Zaki hindered settling index is 4.5, the volume fraction of solids in the suspension is_____________?

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A suspension of glass beads in ethylene glycol has a hindered settling velocity of 1.7 mm/s, while the terminal settling velocity of a single glass bead in ethylene glycol is 17 mm/s. If the Richardson-Zaki hindered settling index is 4.5, the volume fraction of solids in the suspension is_____________?

A. 0.1
B. 0.4
C. 0.6
D. None of these