A centrifuge is used to remove solid particles with a diameter of $5 \mu \mathrm{m}$ and $S G=1.25$ from a dilute aqueous stream. The centrifuge rotates at $1200 \mathrm{rpm}$ and is $3 \mathrm{ft} \mathrm{high}$, the radial distance to the liquid surface is $10 \mathrm{in}$., and the radial distance to the wall is $14 \mathrm{in}$.

(a) Assuming that the particles must strike the centrifuge wall to be removed, what is the maximum capacity of this centrifuge, in gpm?

(b) What is the diameter, in feet, of the gravity settling tank that would be required to do the same job?