Effect Boycott

Finally, we make mention of a settling method that employs the fact that particles when settling in an inclined tube do so faster than if the tube is vertical. This effect is termed the Boycott effect, after the physician A.E. Boycott, who in 1920 made this observation in connection with the sedimentation of blood cells in a tube. A picture of batch sedimentation in an inclined channel is shown in Fig. 5.4.8. The clarified liquid, suspension, and sediment are modeled as three distinct regions separated by kinematic shocks, as in vertical settling. 

For example, the treatment of the so-called Boycott effect by Acrivos and Herbolzheimer (1979) considers the flow of a dispersion in which particles segregate to create stratification between two fluids, one of which is clear and the other packed with particles. 

At present an effective method of separation of liquid from particles in an inclined channel is being used. The increase of the sedimentation velocity of particles was first shown in [43] in the case of particles sedimentation in blood. This effect is known as Boycott s effect. The picture of particle sedimentation is shown in Fig. 8.13. 

---