Month: February 2019

An aqueous solution of methanol is to be distilled in a tray column. High pressure steam is available as a source of heat. For a given reflux ratio and overhead composition, two options are being explored; (i) a reboiler is used and (ii) no reboiler is used but steam is fed directly to the bottom of the column. As compared to option (i), in option (ii) ____________________?

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An aqueous solution of methanol is to be distilled in a tray column. High pressure steam is available as a source of heat. For a given reflux ratio and overhead composition, two options are being explored; (i) a reboiler is used and (ii) no reboiler is used but steam is fed directly to the bottom of the column. As compared to option (i), in option (ii) ____________________?

A. Less number of trays are required
B. Composition of the residue remains unchanged
C. More number of trays are required but the residue composition remains unchanged
D. More number of trays are required and the residue composition is more dilute in methanol

The solvent used in liquid extraction should not have high latent heat of vaporisation, because ______________________?

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The solvent used in liquid extraction should not have high latent heat of vaporisation, because ______________________?

A. The pressure drop and hence the pumg cost will be very high
B. It cannot be recovered by distillation
C. Its recovery cost by distillation may be prohibitively high
D. It will decompose while recovering by distillation

Component A is diffusing in a medium B. The flux NA relative to a stationary point is equal to the flux due to molecular diffusion, if____________________?

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Component A is diffusing in a medium B. The flux NA relative to a stationary point is equal to the flux due to molecular diffusion, if____________________?

A. Mass transfer is accompanied by reaction
B. Diffusion of A is in stagnant medium B
C. Molecular mean free path is high
D. There is equimolar counter diffusion