In a fluidised bed reactor (A) Temperature gradients are very high (B) Temperature is more or less uniform (C) Hot spots are formed (D) Segregation of the solids occurs

In a fluidised bed reactor
(A) Temperature gradients are very high
(B) Temperature is more or less uniform
(C) Hot spots are formed
(D) Segregation of the solids occurs
by

1 Answer

Answer :

(B) Temperature is more or less uniform
by

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Bed pressure drop in an air fluidised bed of catalyst particles (ρp = 200 kg/m3, Dp = 0.05 cm) of 60 cm bed depth and bed porosity of 0.5 expressed in cm of water (manometer) is (A) 90 (B) 60 (C) 45 (D) 30

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Commercial scale production of hydrogen from iron-steam reaction represented by, 3Fe + 3H2O = Fe3O4 + 4H2 , is not practised, as it is (A) A slow reaction (B) A discontinuous reaction (requiring regeneration of iron by water gas intermittently) (C) Still in development stage (by employing fluidised bed technique) (D) All (A), (B) and (C)

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$ Positive diffusion occurs against the concentration gradients. ! Osmosis does not require a semi-permeable membrane.

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Give the principle and working of Fluidised bed dryer.

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Write the advantages and disadvantages of fluidised bed dryer.

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