Acetobacter aceti bacteria conver ethanol to acetic acid under aerobic condition
ID: 846677 • Letter: A
Question
Acetobacter aceti bacteria conver ethanol to acetic acid under aerobic conditions. A continuous fermentation process for vinegar production is proposed using nongrowing A. aceti cells immobilized on the surface of gelatin beads. Air is pumped into the fermenter at a rate of 200 mol/hr. The production target is 2kg/h acetic acid and the maxiumum acetic acid concentration tolerated by the cells is 12 wt%.
1) how much ethanol is required to meet the production target?
2) what amount of water must be used to dilute the ethanol to avoid acid inhibition?
3) what is the composition of the fermenter off-gas?
Explanation / Answer
(a)1.5 kg h-1 ethanol is required.
(b) 14.1 kg h-1 water must be used to dilute the ethanol in the feed stream.
(c) The composition of the fermenter off-gas is 5.2% O2 and 94.8% N2.