Q. Which of the following type(s) of stirrer can be used for microbiological processes?

View solution

Q. The range of width for the baffle in the fermenter is __________ times of vessel diameter

View solution

Q. The average concentration of oxygen in the boundary layers surrounding the bubbles (Co*) in a reactor is normally determined by

View solution

Q. Why vortexing is undesirable in the agitation of biological systems?

View solution

Q. What is the ratio of depth of liquid in vessel to the diameter of tank (H:Dt)?

View solution

Q. Radial flow impellers

View solution

Q. Transient flow range of mixing speed is obtained for

View solution

Q. A typical ceiling fan would be best described as a(n)

View solution

Q. What is the ratio of diameter of impeller to the diameter of tank (Da:Dt)?

View solution

Q. The rate limiting step in the movement of oxygen from the gas phase in a bubble to the cell is the movement of oxygen molecules through

View solution

Q. Penetration theory assumes that turbulent eddies travel from the bulk of the phase to the interface where they remain constant for a constant exposure time (te). The model correlating KL, mass transfer coefficient and DAB, diffusivity can be expressed as

View solution

Q. The oxygen uptake requirements of a microbial population is characterized by the following parameters: μm = 0.2 h­¹, K0 = 0.2 mg O₂.l­¹, Y0 = 0.5 mg dry weight/mg O₂ and C0,crit=0.8 mg.l­¹ The required concentration of cells is 1000 mg.l­¹ and the saturation oxygen concentration of the medium is 5.8 mg.l­¹. The required KLa must be greater than

View solution

Q. Which have the maximum resistance while transferring carbon dioxide from the bulk liquid to an air bubble?

View solution

Q. If liquid density and viscosity remains constant, then the Reynolds number in a stirred tank reactor will vary with the

View solution

Q. Power number is ratio of

View solution

Q. The volume of liquid (VL) in a cylindrical reactor can be calculated from the liquid height (HL) and tank diameter (Dt) using the following equation

View solution

Q. The average fractional gas hold up (H) can be given as (where Zf and Zl are the level of aerated and clear liquid respectively)

View solution

Q. Which of the following(s) is/are non-mechanically agitated reactors?

View solution

Q. Which of the following best explains the reasons for using axial flow impellers in crystallization and precipitation reactions?

View solution

Q. When the height of an aerated bioreactor is increased, it will increase the oxygen transfer rate by

View solution