Q. During aeration, a cylindrical reactor had a height of 10 m. Without aeration, the height was 7.5 m. Under these aeration and mixing conditions, the gas hold up in the reactor is

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Q. A fermentation system has a KLa of 3 s­¹ and a C0* of 5 ppm of O₂. If the bulk liquid is saturated with oxygen then the oxygen transfer rate will be equal to

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Q. Which of the following would be best described as a radial flow impeller?

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Q. Small propellers turn at the speed of either

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Q. In aerobic microorganisms cultures radial flow impellers are used because

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Q. Which of the following is not classified as an axial flow impeller?

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Q. Power number (Np) is also known as

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Q. Flooding is a condition/phenomenon which occur in a bioreactor when

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Q. A cylindrical reactor has a liquid volume of 100,000 litres. It has an aspect ratio the ratio of the channel height to width of 1:1. The height of the liquid in the reactor will be approximately:

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Q. Detergent like substances produced by microorganisms during a fermentation will lead to

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Q. In the design of a paddle agitator, the ratio of paddle diameter to tank diameter is normally taken as

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Q. The oxygen absorption rate can be determined by

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Q. Industrial paddle agitators turn at the speed of

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Q. The dynamic technique is based on the

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Q. The addition of antifoams to an aerated bioreactor will decrease oxygen transfer rates because antifoams

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Q. Which of the following will have the largest interfacial area per unit volume?

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Q. Which device is commonly used for measuring the rate of rotation (rpm) of the stirrer shaft?

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Q. Laminar flow range of mixing speed is obtained for

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Q. Which of the following number is calculated from the diameter and peripheral speed of the impeller?

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Q. A higher liquid height will lead to a higher gas hold up by which the oxygen transfer rate will be

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