A suspension of Bacillus subtilis cells is filtered under constant pressure for recovery of protease. A pilot-scale filter is used to measure filtration properties. The filter area is 0.25 m2, the pressure drop is 360 mmHg, and the filtrate viscosity is 4.0 cP. The cell suspension deposits 22 g cake per liter of filtrate. The following data are measured: (Hints: Change the unit to standard units)
Time (min) 2 3 6 10 15 20
Filtrate volume
(L)
10.8 12.1 18.0 21.8 28.4 32
a) Determine the specific cake resistance and filter medium resistance.
b) What size filter is required to process 4000 L cell suspension in 30 min at a pressure drop of 360 mm Hg?