Operating velocity in a packed tower is usually __________ the flooding velocity. (A) Half (B) Twice (C) Equal to (D) More than

Operating velocity in a packed tower is usually __________ the flooding

velocity.

(A) Half

(B) Twice

(C) Equal to

(D) More than

by

1 Answer

Answer :

(A) Half

by

Related questions

Pick out the wrong statement: (A) Change in barometric pressure does not affect the relative humidity (B) In case of a packed tower, the operating velocity is about half of the flooding velocity, generally (C) 'Elution' means the desorption of the adsorbed solute by a solvent (D) The equilibrium moisture content of the solid can be reduced by increasing the absolute humidity

Description : Pick out the wrong statement: (A) Change in barometric pressure does not affect the relative humidity (B) In case of a packed tower, the operating velocity is about half of the ... (D) The equilibrium moisture content of the solid can be reduced by increasing the absolute humidity

Last Answer : (D) The equilibrium moisture content of the solid can be reduced by increasing the absolute humidity

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)

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

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

The main reason for dividing a tall packed tower into series of small towers is to (A) Minimise the overall pressure drop (B) Avoid flooding (C) Reduce liquid hold up (D) Avoid channelling

Description : The main reason for dividing a tall packed tower into series of small towers is to (A) Minimise the overall pressure drop (B) Avoid flooding (C) Reduce liquid hold up (D) Avoid channelling

Last Answer : (D) Avoid channelling

In a packed absorption tower, if the equilibrium and operating lines are both straight lines, then the ratio, HETP/HTUOG __________ the absorption factor. (A) Increases with increase in (B) Is one at unity value of (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : In a packed absorption tower, if the equilibrium and operating lines are both straight lines, then the ratio, HETP/HTUOG __________ the absorption factor. (A) Increases with increase in (B) Is one at unity value of (C) Both (A) and (B) (D) Neither (A) nor (B)

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

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

In a packed tower, the value of HETP equals HTUOG, when the equilibrium and the operating lines are (where, HETP = height equivalent to a theoretical plate HTUOG = overall gas phase height of a transfer unit). (A) Straight (B) Parallel (C) Both (A) & (B) (D) Neither (A) nor (B

Description : In a packed tower, the value of HETP equals HTUOG, when the equilibrium and the operating lines are (where, HETP = height equivalent to a theoretical plate HTUOG = overall gas phase height of a transfer unit). (A) Straight (B) Parallel (C) Both (A) & (B) (D) Neither (A) nor (B

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

In an absorption column, the flooding velocity for random packing is __________ that for stacked/regular packing. (A) Greater than (B) Smaller than (C) Equal to (D) Either (A), or (B); depends on the type of packing

Description : In an absorption column, the flooding velocity for random packing is __________ that for stacked/regular packing. (A) Greater than (B) Smaller than (C) Equal to (D) Either (A), or (B); depends on the type of packing

Last Answer : (B) Smaller than

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

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

Minimum possible diameter of a packed column is decided mainly bythe(A) Flooding(B) Gas viscosity(C) Liquid density(D) Liquid hold up

Description : Minimum possible diameter of a packed column is decided mainly bythe (A) Flooding (B) Gas viscosity (C) Liquid density (D) Liquid hold up

Last Answer : (A) Flooding

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

Hydrogenation of oil is carried out in a/an __________ in Vanaspati manufacturing plant. (A) Agitated vessel (B) Sieve tray column (C) Bubble cap column (D) Packed tower

Description : Hydrogenation of oil is carried out in a/an __________ in Vanaspati manufacturing plant. (A) Agitated vessel (B) Sieve tray column (C) Bubble cap column (D) Packed tower

Last Answer : (A) Agitated vessel

Diameter of raschig rings used in packed tower in industry is normally around __________ inches. (A) 2 (B) 8 (C) 12 (D) 18

Description : Diameter of raschig rings used in packed tower in industry is normally around __________ inches. (A) 2 (B) 8 (C) 12 (D) 18

Last Answer : (A) 2

Sodium bicarbonate is produced during soda ash manufacture using a __________ tower. (A) Plate (B) Baffle (C) Packed (D) None of these

Description : Sodium bicarbonate is produced during soda ash manufacture using a __________ tower. (A) Plate (B) Baffle (C) Packed (D) None of these

Last Answer : (B) Baffle

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

For liquid flow through a packed bed, the superficial velocity as compared to average velocity through the channel in the bed is (A) More (B) Less (C) Equal (D) Independent of porosity

Description : For liquid flow through a packed bed, the superficial velocity as compared to average velocity through the channel in the bed is (A) More (B) Less (C) Equal (D) Independent of porosity

Last Answer : (B) Less

SO3 is absorbed using H2SO4 in a (A) Cast iron packed tower (B) Stainless steel plate tower (C) Packed steel tower lined with acid proof bricks (D) None of these

Description : SO3 is absorbed using H2SO4 in a (A) Cast iron packed tower (B) Stainless steel plate tower (C) Packed steel tower lined with acid proof bricks (D) None of these

Last Answer : (C) Packed steel tower lined with acid proof bricks

Which of the following is the most suitable for extraction in a system having very low density difference? (A) Mixer-settler extractor (B) Centrifugal extractor (C) Pulsed extractor (D) Packed extraction tower

Description : Which of the following is the most suitable for extraction in a system having very low density difference? (A) Mixer-settler extractor (B) Centrifugal extractor (C) Pulsed extractor (D) Packed extraction tower

Last Answer : (B) Centrifugal extractor

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)

In a moderately sized packed absorption tower, channelling (which is most severe with stacked packings) can be minimised by taking the ratio of tower diameter to packing diameter (A) > 4 :1 (B) < 8 : 1 (C) > 8:1 (D) < 6:1

Description : In a moderately sized packed absorption tower, channelling (which is most severe with stacked packings) can be minimised by taking the ratio of tower diameter to packing diameter (A) > 4 :1 (B) < 8 : 1 (C) > 8:1 (D) < 6:1

Last Answer : (C) > 8:1

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

When the velocity of an enzymatic reaction equals Vmax, substrate concentration is (A) Half of Km (B) Equal to Km (C) Twice the Km (D) Far above the Km

Description : When the velocity of an enzymatic reaction equals Vmax, substrate concentration is (A) Half of Km (B) Equal to Km (C) Twice the Km (D) Far above the Km

Last Answer : Answer : D

In a multipass shell and tube heat exchanger, tube side return pressure loss is equal to __________ the velocity head. (A) Twice (B) Four times (C) Square root of (D) Square of

Description : In a multipass shell and tube heat exchanger, tube side return pressure loss is equal to __________ the velocity head. (A) Twice (B) Four times (C) Square root of (D) Square of

Last Answer : (B) Four times

When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value. (A) Twice (B) Half (C) Equal (D) None of these

Description : When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value. (A) Twice (B) Half (C) Equal (D) None of these

Last Answer : (B) Half

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

Flooding results in (A) High tray efficiency (B) Low tray efficiency (C) High gas velocity (D) Good contact between the fluids

Description : Flooding results in (A) High tray efficiency (B) Low tray efficiency (C) High gas velocity (D) Good contact between the fluids

Last Answer : (B) Low tray efficiency

Flooding in a column results due to (A) High pressure drop (B) Low pressure drop (C) Low velocity of the liquid (D) High temperature

Description : Flooding in a column results due to (A) High pressure drop (B) Low pressure drop (C) Low velocity of the liquid (D) High temperature

Last Answer : (A) High pressure drop

When the temperature and humidity of air is low, we usually use __________ draft cooling tower. (A) Natural (B) Forced (C) Induced (D) None of these

Description : When the temperature and humidity of air is low, we usually use __________ draft cooling tower. (A) Natural (B) Forced (C) Induced (D) None of these

Last Answer : (A) Natural

In sprayers , operating pressures below ___________Kpa are undesirable for hydraulic nozzles other than flooding type

Description : In sprayers , operating pressures below ___________Kpa are undesirable for hydraulic nozzles other than flooding type

Last Answer : 140

Nominal size of the discharge pipe of a pump is usually __________ the nominal size of the inlet pipe. (A) Smaller than (B) Larger than (C) Same as (D) Twice

Description : Nominal size of the discharge pipe of a pump is usually __________ the nominal size of the inlet pipe. (A) Smaller than (B) Larger than (C) Same as (D) Twice

Last Answer : (A) Smaller than

With increase in the liquid flow rate at a fixed gas velocity in a randomly packed counter current gas-liquid absorption column, the gas pressure drop (A) Decreases (B) Remains unchanged (C) Increases (D) Decreases exponentially

Description : With increase in the liquid flow rate at a fixed gas velocity in a randomly packed counter current gas-liquid absorption column, the gas pressure drop (A) Decreases (B) Remains unchanged (C) Increases (D) Decreases exponentially

Last Answer : (C) Increases

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

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, the minimum fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

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 ... fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

Last Answer : (B) 16 mm/s

A satellite of mass "M" is in orbit around the earth. If a second satellite of mass "2M" is to be placed in the same orbit, the second satellite must have a velocity which is: w) half the velocity of the first satellite x) the same as the velocity of the first satellite y) twice the velocity of the first satellite z) four times the velocity of the first satellite

Description : A satellite of mass "M" is in orbit around the earth. If a second satellite of mass "2M" is to be placed in the same orbit, the second satellite must have a velocity which is: w) half ... first satellite y) twice the velocity of the first satellite z) four times the velocity of the first satellite

Last Answer : ANSWER: X -- THE SAME AS THE VELOCITY OF THE FIRST SATELLITE 

Flooding in a vapor-liquid contacting equipment occurs in a tray, when the pressure drop through a tray is __________ the liquid head available in the downcomer. (A) Less than (B) More than (C) Same as (D) Very much less

Description : Flooding in a vapor-liquid contacting equipment occurs in a tray, when the pressure drop through a tray is __________ the liquid head available in the downcomer. (A) Less than (B) More than (C) Same as (D) Very much less

Last Answer : (B) More than

The temperature of water cooled in cooling tower is always __________ temperature of entering air. (A) More than the wet bulb (B) Less than the wet bulb (C) Equal to the wet bulb (D) Equal to the dry bulb

Description : The temperature of water cooled in cooling tower is always __________ temperature of entering air. (A) More than the wet bulb (B) Less than the wet bulb (C) Equal to the wet bulb (D) Equal to the dry bulb

Last Answer : (A) More than the wet bulb

Dams are designed to reduce flooding by ____________. a) Protecting river banks from erosion b) Providing storage for flood water c) Increasing the downstream velocity of flood water ‘ d) Trapping sediment behind the dam so it can't be deposited downstream

Description : Dams are designed to reduce flooding by ____________. a) Protecting river banks from erosion b) Providing storage for flood water c) Increasing the downstream velocity of flood water ‘ d) Trapping sediment behind the dam so it can't be deposited downstream

Last Answer : b) Providing storage for flood water

Channelization of streams is designed to reduce flooding by ___________. a) Speeding the passage of floodwaters b) Reducing bank erosion c) Slowing down river velocity so as to reduce damage d) Increase the meandering of streams

Description : Channelization of streams is designed to reduce flooding by ___________. a) Speeding the passage of floodwaters b) Reducing bank erosion c) Slowing down river velocity so as to reduce damage d) Increase the meandering of streams

Last Answer : a) Speeding the passage of floodwaters

Dams are designed to reduce flooding by _______________. a) Protecting river banks from erosion b) Providing storage for flood water c) Increasing the downstream velocity of flood water d) Trapping sediment behind the dam so it can't be deposited downstream

Description : Dams are designed to reduce flooding by _______________. a) Protecting river banks from erosion b) Providing storage for flood water c) Increasing the downstream velocity of flood water d) Trapping sediment behind the dam so it can't be deposited downstream

Last Answer : b) Providing storage for flood water

Flooding is also a……... algorithm, usually generates ………... of duplicate packets. A. Static, vast number B. dynamic , vast number C. Static, less number D. dynamic , less number

Description : Flooding is also a……... algorithm, usually generates ………... of duplicate packets. A. Static, vast number B. dynamic , vast number C. Static, less number D. dynamic , less number

Last Answer : A. Static, vast number

______ is a static algorithm in which every incoming packet is sent out on every outgoing line except the one it arrives on. This method usually generates vast number of duplicate packets.. A. Flooding B. Wait and watch C. congestion D. both a and c

Description : ______ is a static algorithm in which every incoming packet is sent out on every outgoing line except the one it arrives on. This method usually generates vast number of duplicate packets.. A. Flooding B. Wait and watch C. congestion D. both a and c

Last Answer : A. Flooding

Minimum temperature upto which water can be theoretically cooled down in the cooling tower by evaporative cooling is equal to the __________ temperature of air. (A) Wet bulb (B) Dry bulb (C) Saturation (D) Dew point

Description : Minimum temperature upto which water can be theoretically cooled down in the cooling tower by evaporative cooling is equal to the __________ temperature of air. (A) Wet bulb (B) Dry bulb (C) Saturation (D) Dew point

Last Answer : Option A

Pick out the correct statement. (A) The slope of the stripping line is always less than unity (B) For a given separation in a binary distillation column, with increase in reflux ratio (above the minimum reflux ratio), the fixed cost of the distillation column first increases and then decreases (C) In Ponchon-Savarit method of no. of theoretical plate determination, the stripping and rectifying operating lines are vertical at total reflux (D) Kremser-Brown-Souder's equation is used to calculate the efficiency of a plate tower

Description : Pick out the correct statement. (A) The slope of the stripping line is always less than unity (B) For a given separation in a binary distillation column, with increase in reflux ratio ( ... (D) Kremser-Brown-Souder's equation is used to calculate the efficiency of a plate tower

Last Answer : C) In Ponchon-Savarit method of no. of theoretical plate determination, the stripping and rectifying operating lines are vertical at total reflux

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

Description : 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

Last Answer : (B) Greater than

Flowers which have single ovule in the ovary and are packed into inflorescence are usually pollinated by (a) bee (b) wind (c) bat (d) water.

Description : Flowers which have single ovule in the ovary and are packed into inflorescence are usually pollinated by (a) bee (b) wind (c) bat (d) water.

Last Answer : (b) wind