Home⇒ Medical Science⇒ Bochemical Engineering⇒ Agitation and aeration
| 1-Dont try to cram or spend more time here just read it fast and cover syllabus then practice MCQ's cheptor of same topic to check your progress. . |
| 2-Wrong options are also given but dont concentrate there, Right answer is in bold format. |
| Q1 ⇒ The range of width for the baffle in the fermenter is __________ times of vessel diameter 1/10 to 1/12 [other wrong options] [Discuss in forum] |
| Q2 ⇒ Radial flow impellers Both (a) and (b) [other wrong options] [Discuss in forum] |
| Q3 ⇒ Power number is ratio of imposed forced to intertial force [other wrong options] [Discuss in forum] |
| Q4 ⇒ When liquid is pumped through cooling coil in a stirred tank reactor to cool. Which of the following is not correct? Faster cooling rates at a slower rate of pumping [other wrong options] [Discuss in forum] |
| Q5 ⇒ The Intermig impeller is All of the above [other wrong options] [Discuss in forum] |
| Q6 ⇒ Impeller damage can be minimized by using specially designed axial flow impellers [other wrong options] [Discuss in forum] |
| Q7 ⇒ If the stirrer speed is too slow, bubbles will accumulate and coalescese under the impeller. This phenomenon is known as a flooded impeller [other wrong options] [Discuss in forum] |
| Q8 ⇒ A fermentation system has a KLa of 3 s-1 and a C0* of 5 ppm of O2. If the bulk liquid is completely depleted of oxygen, then the oxygen transfer rate will be equal to 15 mg.l-1.s-1 [other wrong options] [Discuss in forum] |
| Q9 ⇒ For turbulent flow, Reynolds number is correlated with power number as (where K, a constant which depends on the container geometry and shape of stirrer; Rei, is Reynolds number for agitator; Di, stirrer diameter and N, stirrer speed) Np = K [other wrong options] [Discuss in forum] |
| Q10 ⇒ Which of the following impellers generate a flow parallel to the axis of shaft? Axial flow [other wrong options] [Discuss in forum] |
| Q11 ⇒ Which device is commonly used for measuring the rate of rotation (rpm) of the stirrer shaft? Tachometer [other wrong options] [Discuss in forum] |
| Q12 ⇒ Which of the following impellers are used for wide range of viscosities? turbines [other wrong options] [Discuss in forum] |
| Q13 ⇒ If liquid density and viscosity remains constant, then the Reynolds number in a stirred tank reactor will vary with the square of the impeller diameter [other wrong options] [Discuss in forum] |
| Q14 ⇒ Which of the following would be best described as an axial flow impeller? Both (a) and (b) [other wrong options] [Discuss in forum] |
| Q15 ⇒ Power consumption by agitation is all of the above [other wrong options] [Discuss in forum] |
| Q16 ⇒ For aerated mixing vessels in an aqueous solution, the mass transfer coefficient (kL) co-relating power consumption (Pm) and fermenter volume (V) can be expressed as kL ∝ (Pm/V)0.33 [other wrong options] [Discuss in forum] |
| Q17 ⇒ A cylindrical reactor fitted with Rushton Turbine has a liquid volume of 100,000 litres. It has an aspect ratio (the ratio of the channel height to the width) of 2:1. The diameter of the impeller should be approximately: 1.3 m [other wrong options] [Discuss in forum] |
| Q18 ⇒ The addition of antifoams to an aerated bioreactor will decrease oxygen transfer rates because antifoams All of the above answers [other wrong options] [Discuss in forum] |
| Q19 ⇒ Turbulent flow range of mixing speed is obtained for Rei>104 [other wrong options] [Discuss in forum] |
| Q20 ⇒ In a two-phase system where the continuous phase remains in place, the gas hold up can be expressed as (where Vs and Vt are the superficial gas velocity and bubble rise velocity) H = Vs/(Vs+ Vt) [other wrong options] [Discuss in forum] |
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