Pressure drop in a fluidised bed reactor is __________ that in a similar packed bed reactor. (A) Less than (B) Greater than (C) Same as (D) None of these

Pressure drop in a fluidised bed reactor is __________ that in a similar
packed bed reactor.
(A) Less than
(B) Greater than
(C) Same as
(D) None of these
by

1 Answer

Answer :

(B) Greater than
by

Related questions

Fluidised bed reactor is characterised by (A) Uniformity of temperature (B) Comparatively smaller equipment (C) Very small pressure drop (D) Absence of continuous catalyst regeneration facility

Description : Fluidised bed reactor is characterised by (A) Uniformity of temperature (B) Comparatively smaller equipment (C) Very small pressure drop (D) Absence of continuous catalyst regeneration facility

Last Answer : (A) Uniformity of temperature

For flow of fluids through packed bed, the superficial velocity is (A) Less than the average velocity through channels (B) More than the average velocity through channels (C) Dependent on the pressure drop across the bed (D) Same as the average velocity through channels

Description : For flow of fluids through packed bed, the superficial velocity is (A) Less than the average velocity through channels (B) More than the average velocity through channels (C) Dependent on the pressure drop across the bed (D) Same as the average velocity through channels

Last Answer : (A) Less than the average velocity through channels

Pick out the correct statement. (A) For identical gas flow rates, less pressure drop occurs through a plate tower than through a packed tower (B) Plate column can handle greater liquid loads without flooding than packed column, but the liquid hold up is more in the case of plate column (C) For the same duty, plate columns weigh less than packed columns (D) All (A), (B) and (C)

Description : Pick out the correct statement. (A) For identical gas flow rates, less pressure drop occurs through a plate tower than through a packed tower (B) Plate column can handle greater liquid loads without flooding than packed ... duty, plate columns weigh less than packed columns (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

At the same gas flow rate, the pressure drop in a packed tower being irrigated with liquid __________ that in dry packed tower. (A) Is greater than (B) Is lower than (C) Is same as (D) Cannot be predicted as data are insufficient

Description : At the same gas flow rate, the pressure drop in a packed tower being irrigated with liquid __________ that in dry packed tower. (A) Is greater than (B) Is lower than (C) Is same as (D) Cannot be predicted as data are insufficient

Last Answer : (A) Is greater than

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

Description : 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

Last Answer : (B) Temperature is more or less uniform

Lurgi coal gasifier is a pressurised __________ bed reactor. (A) Moving (B) Fixed (C) Fluidised (D) Entrained

Description : Lurgi coal gasifier is a pressurised __________ bed reactor. (A) Moving (B) Fixed (C) Fluidised (D) Entrained

Last Answer : (A) Moving

For a fluidised bed reactor, the most suitable/relevant model is a __________ model. (A) Tank in series (B) Bubbling bed (C) Plug flow (D) None of these

Description : For a fluidised bed reactor, the most suitable/relevant model is a __________ model. (A) Tank in series (B) Bubbling bed (C) Plug flow (D) None of these

Last Answer : (B) Bubbling bed

For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor. (A) Fixed (B) Fluidised bed reactor followed by a fixed (C) Fixed bed reactor followed by a fluidised (D) Fluidised

Description : For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor. (A) Fixed (B) Fluidised bed reactor followed by a fixed (C) Fixed bed reactor followed by a fluidised (D) Fluidised

Last Answer : (B) Fluidised bed reactor followed by a fixed

Oil is hydrogenated using nickel catalyst in a __________ reactor. (A) Batch (B) Slurry (C) Fluidised bed (D) Fixed bed

Description : Oil is hydrogenated using nickel catalyst in a __________ reactor. (A) Batch (B) Slurry (C) Fluidised bed (D) Fixed bed

Last Answer : (B) Slurry

. Lurgi coal gasifier is a pressurised __________ bed reactor. (A) Moving (B) Fixed (C) Fluidised (D) Entrained

Description : . Lurgi coal gasifier is a pressurised __________ bed reactor. (A) Moving (B) Fixed (C) Fluidised (D) Entrained

Last Answer : (A) Moving

. The most widely used crude topping column in refineries is the__________ column.(A) Bubble-cap(B) Packed bed(C) Fluidised bed(D) Perforated plate

Description : . The most widely used crude topping column in refineries is the__________ column. (A) Bubble-cap (B) Packed bed (C) Fluidised bed (D) Perforated plate

Last Answer : (A) Bubble-cap

A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below: Δ P/L = 375 × 10 3 VOM + 10.94 × 10 6 V2 OM (SI units) If water is to be used as the fluidising medium, in actual operation, the above bed has a height = 1 m. What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8

Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system ... What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8

Last Answer : (C) 0.7

Which of the following is the most suitable for very high pressure gas phase reaction? (A) Batch reactor (B) Tubular flow reactor (C) Stirred tank reactor (D) Fluidised bed reactor

Description : Which of the following is the most suitable for very high pressure gas phase reaction? (A) Batch reactor (B) Tubular flow reactor (C) Stirred tank reactor (D) Fluidised bed reactor

Last Answer : (B) Tubular flow reactor

Pressure drop in a packed bed for laminar flow is given by the __________ equation. (A) Kozeny-Carman (B) Blake-Plummer (C) Leva's (D) Fanning friction factor

Description : Pressure drop in a packed bed for laminar flow is given by the __________ equation. (A) Kozeny-Carman (B) Blake-Plummer (C) Leva's (D) Fanning friction factor

Last Answer : (A) Kozeny-Carman

Pressure drop in packed bed for turbulent flow is given by the __________ equation. (A) Kozeny-Carman (B) Blake-Plummer (C) Leva's (D) Hagen-Poiseuille’s

Description : Pressure drop in packed bed for turbulent flow is given by the __________ equation. (A) Kozeny-Carman (B) Blake-Plummer (C) Leva's (D) Hagen-Poiseuille’s

Last Answer : (B) Blake-Plummer

. A 0.5 m high bed made up of a 1 mm dia glass sphere (density 2500 kg/m3 ) is to be fluidised by water (density 1000 kg/m3 ). If at the point of incipient fluidisation, the bed voidage is 40%, the pressure drop across the bed is (A) 4.4 KPa (B) 2.94 KPa (C) 3.7 KPa (D) None of these

Description : . A 0.5 m high bed made up of a 1 mm dia glass sphere (density 2500 kg/m3 ) is to be fluidised by water (density 1000 kg/m3 ). If at the point of incipient fluidisation, the bed voidage is 40%, the pressure drop across the bed is (A) 4.4 KPa (B) 2.94 KPa (C) 3.7 KPa (D) None of these

Last Answer : (A) 4.4 KPa

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

Description : 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

Last Answer : (B) 60

Which of the following will give maximum gas conversion? (A) Fixed bed reactor (B) Fluidised bed reactor (C) Semi-fluidised bed reactor (D) Plug-flow catalytic reactor

Description : Which of the following will give maximum gas conversion? (A) Fixed bed reactor (B) Fluidised bed reactor (C) Semi-fluidised bed reactor (D) Plug-flow catalytic reactor

Last Answer : (C) Semi-fluidised bed reactor

Which of the following is used for calcination of limestone and dolomite in industrial practice? (A) Fluidised bed reactor (B) Moving bed reactor (C) Fixed bed reactor (D) None of these

Description : Which of the following is used for calcination of limestone and dolomite in industrial practice? (A) Fluidised bed reactor (B) Moving bed reactor (C) Fixed bed reactor (D) None of these

Last Answer : (B) Moving bed reactor

In a packed bed absorption column, the channelling will be noted by the (A) Increase in flow rate (B) Sharp drop in pressure drop (C) Sharp rise in pressure drop (D) None of these

Description : In a packed bed absorption column, the channelling will be noted by the (A) Increase in flow rate (B) Sharp drop in pressure drop (C) Sharp rise in pressure drop (D) None of these

Last Answer : (B) Sharp drop in pressure drop

A gas (density = 1.5 kg/m3 , viscosity = 2 × 10 ‒5 kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The pressure drop for another gas, with density of 1.5 kg/m3and viscosity of 3 × 10 ‒5kg/m.s flowing at 3 m/s will be (A) 8400 Pa/m (B) 12600 Pa/m (C) 18900 Pa/m (D) 16800 Pa/m

Description : A gas (density = 1.5 kg/m3 , viscosity = 2 10 -5 kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The ... flowing at 3 m/s will be (A) 8400 Pa/m (B) 12600 Pa/m (C) 18900 Pa/m (D) 16800 Pa/m

Last Answer : (B) 12600 Pa/m

In a dry packed bed, the pressure drop will be changed by increasing the flow rate as (A) V1.8 (B) V-0.8 (C) V (D) V-1

Description : In a dry packed bed, the pressure drop will be changed by increasing the flow rate as (A) V1.8 (B) V-0.8 (C) V (D) V-1

Last Answer : (A) V1.8

For laminar flow of a fluid through a packed bed of spheres of diameter d, the pressure drop per unit length of bed depends upon the sphere diameter as (A) d (B) d 2 (C) d 4 (D) d

Description : For laminar flow of a fluid through a packed bed of spheres of diameter d, the pressure drop per unit length of bed depends upon the sphere diameter as (A) d (B) d 2 (C) d 4 (D) d

Last Answer : (D) d

Pressure drop through plate tower as compared to that through packed tower, for the same duty will be (A) Less (B) More (C) Equal (D) Either (A) or (B); depends on the packing height

Description : Pressure drop through plate tower as compared to that through packed tower, for the same duty will be (A) Less (B) More (C) Equal (D) Either (A) or (B); depends on the packing height

Last Answer : (B) More

For a packed bed reactor; the presence of a long tail in the residence time distribution curve is an indication of: (A) Ideal plug flow (B) Bypass (C) Dead zone (D) Channelling

Description : For a packed bed reactor; the presence of a long tail in the residence time distribution curve is an indication of: (A) Ideal plug flow (B) Bypass (C) Dead zone (D) Channelling

Last Answer : (C) Dead zone

Pick out the wrong statement. (A) Packed towers are preferred for vacuum operation, because the pressure drop through the packing is less and they (packings) also lessen the possibility of tower wall collapse (B) Packed towers are preferred over plate towers for handling corrosive and foamy liquids (C) Diameter of randomly packed tower is normally more than 1.2 metres (D) Due to uneven supply and improper distribution of liquid, problem of channelling, loading & flooding is generally encountered in packed towers

Description : Pick out the wrong statement. (A) Packed towers are preferred for vacuum operation, because the pressure drop through the packing is less and they (packings) also lessen the ... of liquid, problem of channelling, loading & flooding is generally encountered in packed towers

Last Answer : (C) Diameter of randomly packed tower is normally more than 1.2 metres

Multistage operation (as in the case of catalytic oxidation of SO2 ) is not carried out for NH3 synthesis, because of (A) Comparatively higher pressure drop (B) High cost of the high pressure vessel used for the reactor (C) Higher pumping cost (D) Chances of entrainment and disturbance of catalyst bed

Description : Multistage operation (as in the case of catalytic oxidation of SO2 ) is not carried out for NH3 synthesis, because of (A) Comparatively higher pressure drop (B) High cost of the high pressure ... for the reactor (C) Higher pumping cost (D) Chances of entrainment and disturbance of catalyst bed

Last Answer : (B) High cost of the high pressure vessel used for the reactor

A packed tower compared to a plate tower for a particular mass transfer operation (A) Incurs smaller pressure drop (B) Allows installation of cooling coils (C) Is less costly when built in large sizes/diameters (D) Is more suitable, if suspended solids are present in fluid stream

Description : A packed tower compared to a plate tower for a particular mass transfer operation (A) Incurs smaller pressure drop (B) Allows installation of cooling coils (C) Is less costly when built in large sizes/diameters (D) Is more suitable, if suspended solids are present in fluid stream

Last Answer : (A) Incurs smaller pressure drop

Out of the following gas-liquid contacting devices, for a given set of operating conditions, gas pressure drop is the least in __________ tower. (A) Wetted wall (B) Bubble cap (C) Perforated tray (D) Packed

Description : Out of the following gas-liquid contacting devices, for a given set of operating conditions, gas pressure drop is the least in __________ tower. (A) Wetted wall (B) Bubble cap (C) Perforated tray (D) Packed

Last Answer : (A) Wetted wall

Minimum porosity for fluidisation is(A) That corresponding to static bed (B) That corresponding to completely fluidised bed (C) The porosity of the bed when true fluidisation begins (D) Less than that of the' static bed

Description : Minimum porosity for fluidisation is (A) That corresponding to static bed (B) That corresponding to completely fluidised bed (C) The porosity of the bed when true fluidisation begins (D) Less than that of the' static bed

Last Answer : (C) The porosity of the bed when true fluidisation begins

Which of the following is not applicable to fluidised bed combustion of coal? (A) It cannot burn low grade coal (B) It achieves higher fuel combustion efficiency (C) Less heat transfer surface area is required in boilers (D) None of these

Description : Which of the following is not applicable to fluidised bed combustion of coal? (A) It cannot burn low grade coal (B) It achieves higher fuel combustion efficiency (C) Less heat transfer surface area is required in boilers (D) None of these

Last Answer : (A) It cannot burn low grade coal

Thermofor catalytic cracking process is a __________ process. (A) Fixed bed (B) Moving bed (C) Fluidised bed (D) Non-catalytic

Description : Thermofor catalytic cracking process is a __________ process. (A) Fixed bed (B) Moving bed (C) Fluidised bed (D) Non-catalytic

Last Answer : (D) Non-catalytic

Platforming is a __________ process. (A) Moving bed (B) Fluidised bed (C) Non-regenerative & fixed bed (D) Regenerative

Description : Platforming is a __________ process. (A) Moving bed (B) Fluidised bed (C) Non-regenerative & fixed bed (D) Regenerative

Last Answer : (C) Non-regenerative & fixed bed

Sticky material can be dried in a __________ dryer. (A) Tray (B) Rotary (C) Fluidised bed (D) None of these

Description : Sticky material can be dried in a __________ dryer. (A) Tray (B) Rotary (C) Fluidised bed (D) None of these

Last Answer : (A) Tray

Paper industry employs __________ driers.(A) Cylinder (B) Rotary (C) Spray (D) Fluidised bed

Description : Paper industry employs __________ driers. (A) Cylinder (B) Rotary (C) Spray (D) Fluidised bed

Last Answer : (A) Cylinder

Large scale drying of wheat is done in a __________ dryer. (A) Fluidised bed (B) Spouted bed (C) Tray (D) Vacuum rotary

Description : Large scale drying of wheat is done in a __________ dryer. (A) Fluidised bed (B) Spouted bed (C) Tray (D) Vacuum rotary

Last Answer : (B) Spouted bed

Kopper-Totzek coal gasifier (installed in a coal based nitrogeneous fertiliser plant) employs a/an __________ bed gasifier. (A) Entrained (B) Moving (C) Fixed (D) Fluidised

Description : Kopper-Totzek coal gasifier (installed in a coal based nitrogeneous fertiliser plant) employs a/an __________ bed gasifier. (A) Entrained (B) Moving (C) Fixed (D) Fluidised

Last Answer : (A) Entrained

The uniformity of a gas fluidised bed depends upon the __________ of the solid particles. (A) Size (B) Surface properties (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : The uniformity of a gas fluidised bed depends upon the __________ of the solid particles. (A) Size (B) Surface properties (C) Both (A) and (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) and (B)

Calcination of limestone is not done in a __________ kiln for producing lime. (A) Vertical shaft (B) Rotary (C) Fluidised bed (D) Fixed bed

Description : Calcination of limestone is not done in a __________ kiln for producing lime. (A) Vertical shaft (B) Rotary (C) Fluidised bed (D) Fixed bed

Last Answer : (D) Fixed bed

Heat transfer by __________ is almost absent in case of fluidised bed drying operation. (A) Radiation (B) Conduction (C) Convection (D) Both (B) & (C)

Description : Heat transfer by __________ is almost absent in case of fluidised bed drying operation. (A) Radiation (B) Conduction (C) Convection (D) Both (B) & (C)

Last Answer : A) Radiation

Which of the following same diameter columns gives lowest pressure drop per unit height? (A) Bubble-cap column (B) Sieve-plate column (C) Packed column (stacked)

Description : Which of the following same diameter columns gives lowest pressure drop per unit height? (A) Bubble-cap column (B) Sieve-plate column (C) Packed column (stacked)

Last Answer : (C) Packed column (stacked)

Use of raschig rings in place of crushed stones as packing in packed beds (other things being same) (A) Increases pressure drop, increases surface area (B) Increases pressure drop, decreases surface area (C) Decreases pressure drop, increases surface area (D) Decreases pressure drop, decreases surface area

Description : Use of raschig rings in place of crushed stones as packing in packed beds (other things being same) (A) Increases pressure drop, increases surface area (B) Increases pressure drop, decreases ... (C) Decreases pressure drop, increases surface area (D) Decreases pressure drop, decreases surface area

Last Answer : (C) Decreases pressure drop, increases surface area

. __________ column is preferred to be used, when a high liquid hold up is required in a reactor for gas-liquid reaction. (A) Packed (B) Bubble (C) Spray (D) Tray

Description : . __________ column is preferred to be used, when a high liquid hold up is required in a reactor for gas-liquid reaction. (A) Packed (B) Bubble (C) Spray (D) Tray

Last Answer : (B) Bubble

When a high liquid hold up is required in a reactor for gas liquid reaction, use __________ column. (A) Packed (B) Spray (C) Tray (D) Bubble

Description : When a high liquid hold up is required in a reactor for gas liquid reaction, use __________ column. (A) Packed (B) Spray (C) Tray (D) Bubble

Last Answer : (D) Bubble

Channelling in a packed tower results from the (A) High pressure drop (B) Maldistribution of liquid (C) Non-uniformity of packing (D) Both (B) and (C)

Description : Channelling in a packed tower results from the (A) High pressure drop (B) Maldistribution of liquid (C) Non-uniformity of packing (D) Both (B) and (C)

Last Answer : (D) Both (B) and (C)

Which of these columns incurs the lowest pressure drop? (A) Packed column (with stacked packing) (B) Packed column (with dumped packing) (C) Bubble plate column (D) Pulse column

Description : Which of these columns incurs the lowest pressure drop? (A) Packed column (with stacked packing) (B) Packed column (with dumped packing) (C) Bubble plate column (D) Pulse column

Last Answer : (A) Packed column (with stacked packing)

Under conditions of flooding in packed tower, the gas pressure drop (A) Decreases rapidly (B) Increases rapidly (C) Remain constant (D) Is maximum

Description : Under conditions of flooding in packed tower, the gas pressure drop (A) Decreases rapidly (B) Increases rapidly (C) Remain constant (D) Is maximum

Last Answer : (D) Is maximum

Very tall packed towers are divided into series of beds to (A) Reduce the overall pressure drop (B) Avoid channelling (C) Reduce liquid hold-up (D) Avoid flooding

Description : Very tall packed towers are divided into series of beds to (A) Reduce the overall pressure drop (B) Avoid channelling (C) Reduce liquid hold-up (D) Avoid flooding

Last Answer : (B) Avoid channelling

Plate towers are preferred to packed towers, when large temperature changes are involved, because of the reason that the (A) Packing may be crushed due to thermal expansion/contraction of the components of the equipments (B) Pressure drop in the equipment will be very high (C) Viscosity variation of the fluids may cause channelling/flooding (D) None of these

Description : Plate towers are preferred to packed towers, when large temperature changes are involved, because of the reason that the (A) Packing may be crushed due to thermal expansion/contraction of the ... C) Viscosity variation of the fluids may cause channelling/flooding (D) None of these

Last Answer : (A) Packing may be crushed due to thermal expansion/contraction of the components of the equipments

The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives (A) Low pressure drop and high hold up (B) High pressure drop and low hold up (C) Low pressure drop and low hold up (D) High pressure drop and high hold up

Description : The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives (A) Low pressure drop and high hold up (B) High pressure drop and low hold ... C) Low pressure drop and low hold up (D) High pressure drop and high hold up

Last Answer : (C) Low pressure drop and low hold up