Process Equipment and Plant Design

Low pressure steam (with saturation temperature between 105 to 120°C) is usually used in the vacuum evaporators, which normally employ a vacuum of about _______________ mm Hg (referred to a 760 mm mercury barometer)?

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Low pressure steam (with saturation temperature between 105 to 120°C) is usually used in the vacuum evaporators, which normally employ a vacuum of about _______________ mm Hg (referred to a 760 mm mercury barometer)?

A. 250
B. 450
C. 650
D. 750

In a double pipe (concentric) heat exchanger, the hydraulic radius for heat transfer (for a fluid flowing through the annulus) would be_________________?

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In a double pipe (concentric) heat exchanger, the hydraulic radius for heat transfer (for a fluid flowing through the annulus) would be_________________?

A. Same as that for fluid flow
B. Less than that for fluid flow
C. More than that for fluid flow
D. D2 – D1 (D1 and D2 are I.D. of inner and outer pipes respectively)

At the following point for a given packing and set of fluids, the pressure drop per metre of packed height, with variation in fluid rates and operating pressure____________________?

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At the following point for a given packing and set of fluids, the pressure drop per metre of packed height, with variation in fluid rates and operating pressure____________________?

A. Increases
B. Decreases
C. Remain same
D. May increase or decrease depending upon the solubility of the gas in the liquid