What's the principle of this purifier ?

Purifier working and is there any equation for it?

Principle: A purifier works on the difference between the specific gravity of two different liquids/Stoke’s law
And it can't separate salt out of seawater. Why? Comment down.
High Centrifugal Forces are developed and Heavier particles move towards the outer side of the Bowl

Oil and Water liquids with Different Densities
Oil and Water (liquids with Different Densities)

The Force of separation Equation:

separation by gravity
separation by gravity
ω = Angular velocity
r = Effective radius
ρw = density of water
ρo = density of oil
Fs= seperation force

The Force of separation can be increased if we keep this in a rotating cylinder. This is called a centrifuge. Then the "g" changes to ω² r

Fs =  (pi/6)  x D3 (ρw-ρo) *  ω² r
 Separation just by centrifugal force.

Settling Velocity Equation:

Equation showing Settling Velocity
PIC: Equation showing Settling Velocity
v = Settling velocity (m/s)
rω² = Acceleration in centrifugal Feild (m/s²)

d = Diameter of the particle (m)

ρp = Density of Particle (Kg/m


ρl = density of Liquid medium (Kg/m



= viscosity of the medium kg/(m.s)

A Must Watch Video For Beginners:

A Cartoon Showing Purifier Setting Speed to shape Formation

Further reference :

Stoke's law Settling Velocity (Derivation not needed for Exam)
Note: If you are a trainee then watching all the youtube videos about purifiers might confuse you initially. Alcap, clarifier, purifier, hi-dens, Alfa Laval, and some videos may include different desludging mechanisms each video is different. 

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