Particle Technology

Filtration

Problems 4.10

Question 2
The equations you require will be reviewed when you need to use them. Initially, this question starts by calculating some of the physical conditions given by the filtration: volume of solids present, volume liquid retained in the cake - hence filtrate volume. You will then use all of this data in the constant pressure filtration equation to calculate the time required for the filtration.

Five litres of a 10% w/w slurry of chalk (density of 2670 kg m^-3) in water (viscosity of 0.001 Pa s) was filtered under constant pressure on a filter leaf of 0.0314 m² area. The specific surface of the chalk is 3x10⁶ m^-1 and the cake can be assumed to have had a porosity of 50%.

	a) 100 b) 500 c) 200 d) 250
Note, you need to convert %w/w into %v/v - as you want the volume of solids