Both Saccharomyces cerevisiae yeast and Zymomonas mobilis bacteria produce ethanol from glucose under anaerobic conditions without external electron acceptors. The biomass yield from glucose is 0.11 g g-1 for yeast and 0.05 g g-I for Z. mobilis. In both cases the nitrogen source is NH 3. Both cell compositions are represented by the formula CH 1.800.5N0.2. Compare actual yield with theoretical maximum for Zymomonas mobilis bacteria ?

#Question id: 14196

#Section 5: Bioprocess Engineering and Process Biotechnology

A fluidized-bed, immobilized-cell bioreactor is used for the conversion of glucose to ethanol by Z. mobilis cells immobilized in k-carrageenan gel beads. The dimensions of the bed are 10 cm (diameter) by 200 cm. Since the reactor is fed from the bottom of the column and because of CO₂ gas evolution, substrate and cell concentrations decrease with the height of the column. The average cell concentration at the bottom of the column is X₀ = 45 g/l, and the average cell concentration decreases with the column height according to the following equation:

where Z is the column height (cm). The specific rate of substrate consumption is q_S = 2 g S/g cells. h. The feed flow rate and glucose concentration in the feed are 5 l/h and 160 g glucose/l, respectively.

Determine the substrate (glucose) concentration in the effluent

#Question id: 14197

#Section 5: Bioprocess Engineering and Process Biotechnology

#Question id: 14198

#Section 5: Bioprocess Engineering and Process Biotechnology

which of the following do not come under continuous filtration?

#Question id: 14199

#Section 5: Bioprocess Engineering and Process Biotechnology

#Question id: 14200

#Section 5: Bioprocess Engineering and Process Biotechnology

A fluidized-bed, immobilized-cell bioreactor is used for the conversion of glucose to ethanol by Z. mobilis cells immobilized in k-carrageenan gel beads. The dimensions of the bed are 10 cm (diameter) by 200 cm. Since the reactor is fed from the bottom of the column and because of CO₂ gas evolution, substrate and cell concentrations decrease with the height of the column. The average cell concentration at the bottom of the column is X₀ = 45 g/l, and the average cell concentration decreases with the column height according to the following equation:

where Z is the column height (cm). The specific rate of substrate consumption is q_S = 2 g S/g cells . h. The feed flow rate and glucose concentration in the feed are 5 l/h and 160 g glucose/l, respectively.

Determine the ethanol concentration in the effluent (g/l . h) if YP/S = 0.48 g ethanol/g glucose

#Question id: 14201

#Section 5: Bioprocess Engineering and Process Biotechnology

A fluidized-bed, immobilized-cell bioreactor is used for the conversion of glucose to ethanol by Z. mobilis cells immobilized in k-carrageenan gel beads. The dimensions of the bed are 10 cm (diameter) by 200 cm. Since the reactor is fed from the bottom of the column and because of CO₂ gas evolution, substrate and cell concentrations decrease with the height of the column. The average cell concentration at the bottom of the column is X₀ = 45 g/l, and the average cell concentration decreases with the column height according to the following equation:

where Z is the column height (cm). The specific rate of substrate consumption is q_S = 2 g S/g cells . h. The feed flow rate and glucose concentration in the feed are 5 l/h and 160 g glucose/l, respectively.

Determine the ethanol productivity (g/l . h) if YP/S = 0.48 g ethanol/g glucose.

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