Particle Technology

centrifugal separation

Problems 8.6

Question 1.v


The diagram below illustrates a homogeneous oil emulsion contained in a circular channel rotating at 1000 rpm. The diameter of the outer circle is 30 cm, and the distance between the walls, i.e. the channel width is 2.5 cm.


centrifuge ring

If the oil is less dense than the surrounding water an oil droplet will travel inwards on the application of a centrifugal field force, just as oil floats in a gravitational field.


In the integration of the centrifugal rate expression with respect to time and radial distance, the upper or top limit of the integration of radial position is (cm):

  a) 30
b) 12.5
c) 15
c) 27.5
Note, the question really asks: is the oil drop moving inwards or outwards and what, therefore, will be the radial position that it is heading towards?

Hint Calculator Ready to move on

Home      Book download      Video solutions      Interactive problems      Problem solutions      Size Analysis Expert system