Q. Which of the following impellers will provide radial flow?

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Q. When liquid is pumped through cooling coil in a stirred tank reactor to cool. Which of the following is not correct?

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Q. Swirling and vortex formation can be prevented by

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Q. Power number is expressed as

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Q. The power consumption in a stirring vessel can be assessed by using a

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Q. Surface renewal theory predicts that the mass transfer coefficient is

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Q. The oxygen transfer rate in a bioreactor will increase if

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Q. Which of the following impellers are used for wide range of viscosities?

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

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

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

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

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

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Q. Radial flow impellers

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Q. Transient flow range of mixing speed is obtained for

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

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

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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

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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

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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

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