E. coli have a maximum respiration rate, qO2max, of about 240-mg O2/g-dry wt-h. It is desired to achieve a cell mass of 20 g dry wt/l. The kLa is 120 h-1 in a 1000-l reactor (800 l working volume). A gas stream enriched in oxygen is used (i.e., 80% O2) which gives a value of C* = 28 mg/L. If oxygen becomes limiting, growth and respiration slow; for example,

                                     

   where CL is the dissolved oxygen concentration in the fermenter. What is CL when the cell mass is  at 20 g/l?

#Question id: 14162

#Section 5: Bioprocess Engineering and Process Biotechnology

A continuous process is set up for treatment of wastewater. Each day, 10⁵ kg cellulose and 10³ kg bacteria enter in the feed stream, while 10⁴ kg cellulose and 1.5 x 10⁴ kg bacteria leave in the effluent. The rate of cellulose digestion by the bacteria is 7 x 10⁴ kg d^-1. The rate of bacterial growth is 2 x 10⁴ kg d^-1 ; the rate of cell death by lysis is 5 x 10² kg d^-1. Write balances for cellulose and bacteria in the system.

#Question id: 14163

#Section 4: Fundamentals of Biological Engineering

A stream of growth medium containing 60% glucose and 40% growth factor A flowing at 500 kg per hour was divided into two feed streams for different cell cultures. One fourth of the growth medium was sent to fermenter 1 and the rest was sent to fermenter 2. What is the flow rates of glucose and growth factor A in the feed streams for the two fermenters

#Question id: 14163

#Section 5: Bioprocess Engineering and Process Biotechnology

A stream of growth medium containing 60% glucose and 40% growth factor A flowing at 500 kg per hour was divided into two feed streams for different cell cultures. One fourth of the growth medium was sent to fermenter 1 and the rest was sent to fermenter 2. What is the flow rates of glucose and growth factor A in the feed streams for the two fermenters

#Question id: 14164

#Section 4: Fundamentals of Biological Engineering

Stoichiometric equations are used to represent growth of microorganisms provided a ' molecular formula' for the cells is available. The molecular formula for biomass is obtained by measuring the amounts of C, N, H, O and other elements in cells. For a particular bacterial strain, the molecular formula was determined to be C_4.4H_7.30 _1.2N_0.86 . These bacteria are grown under aerobic conditions with hexadecane (C₁₆H₃₄) as substrate. The reaction equation describing growth is:

  Assuming 100% conversion, what is the yield of cells from hexadecane in g g^-l?   

#Question id: 14164

#Section 5: Bioprocess Engineering and Process Biotechnology

Stoichiometric equations are used to represent growth of microorganisms provided a ' molecular formula' for the cells is available. The molecular formula for biomass is obtained by measuring the amounts of C, N, H, O and other elements in cells. For a particular bacterial strain, the molecular formula was determined to be C_4.4H_7.30 _1.2N_0.86 . These bacteria are grown under aerobic conditions with hexadecane (C₁₆H₃₄) as substrate. The reaction equation describing growth is:

  Assuming 100% conversion, what is the yield of cells from hexadecane in g g^-l?   

#Question id: 14165

#Section 4: Fundamentals of Biological Engineering

Stoichiometric equations are used to represent growth of microorganisms provided a ' molecular formula' for the cells is available. The molecular formula for biomass is obtained by measuring the amounts of C, N, H, O and other elements in cells. For a particular bacterial strain, the molecular formula was determined to be C4.4H7.30 1.2N0.86 . These bacteria are grown under aerobic conditions with hexadecane (C16H34) as substrate. The reaction equation describing growth is:

Assuming 100% conversion, what is the yield of cells from oxygen in g g-l?