observed laboratory rates, actual rates are much higher than this, owing, assumably, to clumping of the particles. Now consider the sction in a cream separator having a bowl 6 in, in diameter and operating at 8600 rpm. Using the combined equation 7.12 and assuming that the average reaction is 2 in. from the bowl axis, we find 410 X 0.000922 0.032 ft per sec or 0.38 in. per sec The actual rate would be higher than this due to elumping. CYCLONE SEPARATOR The cyclone separator or collector is used extensively in process. ing and other operations as a device for collecting the end product. It is also frequently used in connection with pneumatic conveying of products and wastes from processing. 7.23. Theory. The basis of operation can be shown from Fig. 7.14. The air and material enter tangentially at the top and de- scend with a circular motion described by an outer vortex. The material is separated during the downward descent, and the clean air ascends in a tighter vortex at the center and is discharged. A particle that has entered the eyclone is acted upon by two forces, C, and w. The centrifugal furce, C, which acts upon the particle is(7.14) where w weight of particle, Ib V linear or tangential velocity, ft per sec g acceleration of gravity, 32.2 ft per sec R radius of rotation, ft Therefore, the separating force Fis(7.15) The performance factor s is(7.16)