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: 14302

#Section 5: Bioprocess Engineering and Process Biotechnology

Pseudomonas sp. has a mass doubling time of 2.4 h when grown on acetate. The saturation constant using this substrate is 1.3 g/l (which is unusually high), and cell yield on acetate is 0.46 g cell/g acetate. If we operate a chemostat on a feed stream containing 38 g/l acetate, find the Substrate concentration when the dilution rate is 0.8Dmax?

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#Question id: 14303

#Section 5: Bioprocess Engineering and Process Biotechnology

Pseudomonas sp. has a mass doubling time of 2.4 h when grown on acetate. The saturation constant using this substrate is 1.3 g/l (which is unusually high), and cell yield on acetate is 0.46 g cell/g acetate. If we operate a chemostat on a feed stream containing 38 g/l acetate, find the Maximum dilution rate?

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#Question id: 14304

#Section 5: Bioprocess Engineering and Process Biotechnology

Pseudomonas sp. has a mass doubling time of 2.4 h when grown on acetate. The saturation constant using this substrate is 1.3 g/l (which is unusually high), and cell yield on acetate is 0.46 g cell/g acetate. If we operate a chemostat on a feed stream containing 38 g/l acetate, find the Cell productivity at 0.8 Dmax?

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#Question id: 14305

#Section 5: Bioprocess Engineering and Process Biotechnology

Ethanol is to be used as a substrate for single-cell protein production in a chemostat. The available equipment can achieve an oxygen transfer rate of 10 g O₂/l of liquid per hour. Assume the kinetics of cell growth on ethanol is of the Monod type, with µm = 0.5 h^–1, K_s = 30 mg/l, YX/S = 0.5 cells/g ethanol, and YO2/S = 2 g O2/g EtOH. We wish to operate the chemostat with an ethanol concentration in the feed of 22 g/L. We also wish to maximize the biomass productivity and minimize the loss of unused ethanol in the effluent. Determine the required dilution rate

#Question id: 14306

#Section 5: Bioprocess Engineering and Process Biotechnology

Pseudomonas putida with mm = 0.5 h^-1 is cultivated in a continuous culture under aerobic conditions where D = 0.28 h^-1 . The carbon and energy source in the feed is lactose with aconcentration of S₀ = 2 g/l. The effluent lactose concentration is desired to be S = 0.1 g/l. If the growth rate is limited by oxygen transfer, by using the following information:

Determine the steady-state biomass concentration (X)

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