#Question id: 15894
#Section 6: Plant, Animal and Microbial Biotechnology
#Question id: 14334
#Section 5: Bioprocess Engineering and Process Biotechnology
Laboratory-scale fermenters are usually mixed using small stirrers with electric motors rated between 100 and 500 W. One such motor is used to drive a 7cm turbine impeller in a small reactor containing fluid with the properties of water. The stirrer speed is 900 rpm. Estimate the power requirements for this process.
#Question id: 19954
#Section 5: Bioprocess Engineering and Process Biotechnology
#Question id: 14310
#Section 5: Bioprocess Engineering and Process Biotechnology
Glucose is converted to ethanol by immobilized yeast cells
entrapped in gel beads. The specific rate of ethanol production is: qP
= 0.2 g ethanol/g-cell-h. The effectiveness factor for an average bead is 0.8.
Each bead contains 50 g/L of cells. The voids volume in the column is 40%.
Assume growth is negligible (all glucose is converted into ethanol). The feed
flow rate is F = 400 l/h and glucose concentration in the feed is S0i
= 150 g glucose/l. The diameter of the column is 1 m and the yield coefficient
is about 0.49 g ethanol/g glucose. The column height is 4 m. What is the
ethanol concentration in the exit stream?
#Question id: 14617
#Section 2: General Biology