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TLS Online TPP Program

#Question id: 11282

Which of the following ecosystems would likely have the largest net primary productivity per hectare and why?

#Part-B Specialized Branches in Biotechnology
  1. open ocean, because of the total biomass of photosynthetic autotrophs
  2. grassland, because of rapid growth, the small standing crop biomass that results from consumption by herbivores, and rapid decomposition
  3. tundra, because of the incredibly rapid period of growth during the summer season
  4. deep ocean, due to the high activity of chemoautotrophs at deep sea vents
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TLS Online TPP Program

#Question id: 14257

#Part-B Specialized Branches in Biotechnology

The kLa of a small bubble column (2 l) has been measured as 20 h-1 at an airflow of 4 l/m in. If the rate of oxygen uptake by a culture of Catharanthus roseus is 0.2 mmol O2/g dry weight-h and if the critical oxygen concentration must be above 10% of saturation (about 8 mg/l), what is the maximum concentration of cells that can be maintained in the reactor?
TLS Online TPP Program

#Question id: 14258

#Part-B Specialized Branches in Biotechnology

C. roseus cells immobilized in Ca-alginate beads of diameter 0.5 mm are used for production of indole alkaloids (IA) in a fluidized-bed bioreactor. The rate limiting nutrient is glucose and no intraparticle diffusion limitations exist. Use the following data: Flow rate of the feed: Q = 1 l/h, Glucose in the feed: So = 30 g/l, Plant Cell Concentration: X = 6 g/l reac. The rate constant for IA formation: k = 5 d-1 (g/l)-1 Ks = 0.4 g/l, Column diameter: Do = 0.15 m. Growth is negligible and Monod kinetics is valid. For 95% glucose conversion determine required hydraulic residence time.
TLS Online TPP Program

#Question id: 14259

#Part-B Specialized Branches in Biotechnology

C. roseus cells immobilized in Ca-alginate beads of diameter 0.5 mm are used for production of indole alkaloids (IA) in a fluidized-bed bioreactor. The rate limiting nutrient is glucose and no intraparticle diffusion limitations exist. Use the following data: Flow rate of the feed: Q = 1 l/h, Glucose in the feed: So = 30 g/l, Plant Cell Concentration: X = 6 g/l reac. The rate constant for IA formation: k = 5 d-1 (g/l)^-1 Ks = 0.4 g/l, Column diameter: Do = 0.15 m. Growth is negligible and Monod kinetics is valid. For 95% glucose conversion determine volume. 
TLS Online TPP Program

#Question id: 14260

#Part-B Specialized Branches in Biotechnology

C. roseus cells immobilized in Ca-alginate beads of diameter 0.5 mm are used for production of indole alkaloids (IA) in a fluidized-bed bioreactor. The rate limiting nutrient is glucose and no intraparticle diffusion limitations exist. Use the following data: Flow rate of the feed: Q = 1 l/h, Glucose in the feed: So = 30 g/l, Plant Cell Concentration: X = 6 g/l reac. The rate constant for IA formation: k = 5 d-1 (g/l)^-1 Ks = 0.4 g/l, Column diameter: Do = 0.15 m. Growth is negligible and Monod kinetics is valid. For 95% glucose conversion determine height of the column 
TLS Online TPP Program

#Question id: 14268

#Part-B Specialized Branches in Biotechnology

An activated-sludge waste treatment system is required to reduce the amount of BOD5 from 1000 mg/l to 20 mg/l at the exit. The sedimentation unit concentrates biomass by a factor of 3. Kinetic parameters are µm = 0.2 h-1 , Ks = 80 mg/l, kd = 0.01 h-1 , and Y M X/S = 0.5 g MLVSS/g BOD5. The flow of waste water is 10000 l/h and the size of the treatment basin is 50,000 l. What is the value of the solids residence time?
TLS Online TPP Program

#Question id: 14270

#Part-B Specialized Branches in Biotechnology

Consider a well-mixed waste treatment system for a small-scale system. The system is operated with a reactor of 1000 l and flow rate of 100 l/h. The separator concentrates biomass by a factor of 2. The recycle ratio is 0.7. The kinetic parameters are µm = 0.5 h-1 , Ks = 0.2 g/l, Y M X/S = 0.5 g/g, and kd = 0.05 h-1 . What is the exit substrate concentration?