#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: 14311
#Section 5: Bioprocess Engineering and Process Biotechnology
Consider following fig, which applies to a fed-batch system.
Assume at t = 0, V = 100 l, X = 2 g/l, m = 1 h-1 , S0 = 4 g/l, and S = 0.01 g/l. V is increased at a constant rate such that dV/dt = 20 l/h = F (or flow rate) and X is constant at all times. What is µ at t = 5 h?
#Question id: 14312
#Section 5: Bioprocess Engineering and Process Biotechnology
An industrial waste-water stream is fed to a stirred-tank
reactor continuously and the cells are recycled back to the reactor from the
bottom of the sedimentation tank placed after the reactor. The following are
given for the system: F = 100 l/h; S0 = 5000 mg/l; mm = 0.25 h-1 ; Ks = 200
mg/l; α (recycle ratio) = 0.6; C (cell
concentration factor) = 2; Y M X/S = 0.4. The effluent
concentration is desired to be 100 mg/l. Determine the required reactor volume.
#Question id: 14313
#Section 5: Bioprocess Engineering and Process Biotechnology
An industrial waste-water stream is fed to a stirred-tank
reactor continuously and the cells are recycled back to the reactor from the
bottom of the sedimentation tank placed after the reactor. The following are
given for the system: F = 100 l/h; S0 = 5000 mg/l; mm = 0.25 h-1 ; Ks = 200
mg/l; α (recycle ratio) = 0.6; C (cell
concentration factor) = 2; Y M X/S = 0.4. The effluent
concentration is desired to be 100 mg/l. Determine the cell concentration in the
reactor and in the recycle stream.
_____________
#Question id: 14314
#Section 5: Bioprocess Engineering and Process Biotechnology
An industrial waste-water stream is fed to a stirred-tank
reactor continuously and the cells are recycled back to the reactor from the
bottom of the sedimentation tank placed after the reactor. The following are
given for the system: F = 100 l/h; S0 = 5000 mg/l; mm = 0.25 h^-1 ; Ks = 200
mg/l; α (recycle ratio) = 0.6; C (cell
concentration factor) = 2; Y M X/S = 0.4. The effluent
concentration is desired to be 100 mg/l. The effluent concentration is desired to be
100 mg/l. If the residence time is 2 h in the sedimentation tank, determine the
volume of the sedimentation tank and cell concentration in the effluent of the
sedimentation tank.
#Question id: 14315
#Section 5: Bioprocess Engineering and Process Biotechnology
Anaerobic digestion of volatile acids by methane bacteria is
represented by the equation:
The composition of methane bacteria is approximated by the empirical formula CH1.4Oo.40N0.20. For each kg acetic acid consumed, 0.67 kg CO 2 is evolved. How does the yield of methane under these conditions compare with the maximum possible yield?