A viscous solution containing particles with a density of 1461 kg/m3 is to be clarified by centrifugation. The solution density is 801 kg/m3 and its viscosity is 100 cP. The centrifuge has a bowl with r2 = 0.02225 m, r1 = 0.00716 m, and a bowl height of 0.197 m. The centrifuge rotates at 23,000 rev/min and the flow rate is 0.002832 m3/h. The critical particle diameter of the largest particle in the exit stream is 0.747 µm.
(A.) The physical characteristic of the centrifuge (area of the gravitational settler) is:
a. 259.1 m2
b. 169.1 m2
c. 196.1 m2
d. 296.1 m2
(B.) A new centrifuge having the following dimensions is to be used: r2 = 0.0445 m, r1 = 0.01432 m, b = 0.394 m, and N = 26,000 rev/min. The new scale-up flow rate using the same solution is:
a. 8.77x10-5 m3/s
b. 8.05x10-6 m3/s
c. 8.05x10-3 m3/s
d. 5.08x10-4 m3/s