A backward feed multiple effect evaporator is better than forward feed for concentrating cold feed, because it provides (A) Higher economy (B) Lower capacity (C) Both (A) & (B) (D) Lower economy

A backward feed multiple effect evaporator is better than forward feed

for concentrating cold feed, because it provides

(A) Higher economy

(B) Lower capacity

(C) Both (A) & (B)

(D) Lower economy

by

1 Answer

Answer :

(A) Higher economy

by

Related questions

Fqra cold viscous feed, backward feed gives __________ than forward feed. (A) A higher capacity (B) A lower capacity (C) Lower economy (D) None of these

Description : Fqra cold viscous feed, backward feed gives __________ than forward feed. (A) A higher capacity (B) A lower capacity (C) Lower economy (D) None of these

Last Answer : (A) A higher capacity

For a cold dilute feed to produce thick viscous liquor, backward feeding as compared to forward feeding results in (A) Increased economy (B) Decreased economy (C) Lower capacity (D) No effect on economy

Description : For a cold dilute feed to produce thick viscous liquor, backward feeding as compared to forward feeding results in (A) Increased economy (B) Decreased economy (C) Lower capacity (D) No effect on economy

Last Answer : (A) Increased economy

A multiple effect evaporator as compared to a single effect evaporator of the same capacity has (A) Lower heat transfer area (B) Lower steam economy (C) Higher steam economy (D) Higher solute concentration in the product

Description : A multiple effect evaporator as compared to a single effect evaporator of the same capacity has (A) Lower heat transfer area (B) Lower steam economy (C) Higher steam economy (D) Higher solute concentration in the product

Last Answer : (C) Higher steam economy

For concentrating an aqueous solution of a material like anhydrous Na2SO4, whose solubility decreases with rise in temperature, the most suitable evaporator is a __________ evaporator. (A) High pressure (B) Vacuum (C) Backward feed (D) None of these

Description : For concentrating an aqueous solution of a material like anhydrous Na2SO4, whose solubility decreases with rise in temperature, the most suitable evaporator is a __________ evaporator. (A) High pressure (B) Vacuum (C) Backward feed (D) None of these

Last Answer : (B) Vacuum

. A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because (A) Total heat transfer area of all the effects is -less than that in a single effect evaporator system (B) Total amount of vapor produced per Kg of feed steam in a multiple effect system is much higher than in a single effect (C) Boiling point elevation in a single effect system is much higher than that in any effect in a multi-effect system (D) Heat transfer co-efficient in a single effect is much lower than that in any effect in a multi-effect system

Description : . A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because (A) Total heat transfer area of ... in a single effect is much lower than that in any effect in a multi-effect system

Last Answer : (B) Total amount of vapor produced per Kg of feed steam in a multiple effect system is much higher than in a single effect

A multiple effect evaporator has a capacity to process 4000 kg of solid caustic soda per day, when it is concentrating from 10% to 25% solids. The water evaporated in kg per day is (A) 6000 (B) 24000 (C) 60000 (D) 48000

Description : A multiple effect evaporator has a capacity to process 4000 kg of solid caustic soda per day, when it is concentrating from 10% to 25% solids. The water evaporated in kg per day is (A) 6000 (B) 24000 (C) 60000 (D) 48000

Last Answer : (B) 24000

For evaporation of viscous solution in a multiple effect evaporator, the preferred feeding scheme is (A) Forward (B) Backward (C) Parallel (D) None of these

Description : For evaporation of viscous solution in a multiple effect evaporator, the preferred feeding scheme is (A) Forward (B) Backward (C) Parallel (D) None of these

Last Answer : (B) Backward

. In a backward feed multiple effect evaporator (A) Feed is introduced in the first effect (B) Feed flows from low pressure to high pressure (C) No pumps are required between successive effects (D) None of these

Description : . In a backward feed multiple effect evaporator (A) Feed is introduced in the first effect (B) Feed flows from low pressure to high pressure (C) No pumps are required between successive effects (D) None of these

Last Answer : (B) Feed flows from low pressure to high pressure

In a forward feed multiple effect evaporator unit (A) Viscosity of liquid is highest in first effect (B) Transfer from effect to effect is done by pumps (C) No pump is required to withdraw the product from the last effect (D) None of these

Description : In a forward feed multiple effect evaporator unit (A) Viscosity of liquid is highest in first effect (B) Transfer from effect to effect is done by pumps (C) No pump is required to withdraw the product from the last effect (D) None of these

Last Answer : (D) None of these

In a forward feed multiple effect evaporator, the pressure is (A) Highest in last effect (B) Lowest in last effect (C) Same in all effects (D) Dependent on the number of effects

Description : In a forward feed multiple effect evaporator, the pressure is (A) Highest in last effect (B) Lowest in last effect (C) Same in all effects (D) Dependent on the number of effects

Last Answer : (B) Lowest in last effect

For hot feed, forward feeding as compared to backward feeding results in __________ economy. (A) Increased (B) Decreased (C) No effect on (D) None of these

Description : For hot feed, forward feeding as compared to backward feeding results in __________ economy. (A) Increased (B) Decreased (C) No effect on (D) None of these

Last Answer : (A) Increased

The advantage of backward feed multiple effect evaporators over forward feed units is that (A) Heat sensitive material can be handled (B) There is no additional cost of pumping (C) Most concentrated liquid is at highest temperature (D) Equal heat transfer co-efficients exist in various effects

Description : The advantage of backward feed multiple effect evaporators over forward feed units is that (A) Heat sensitive material can be handled (B) There is no additional cost of pumping ... liquid is at highest temperature (D) Equal heat transfer co-efficients exist in various effects

Last Answer : (C) Most concentrated liquid is at highest temperature

Economy of a multiple effect evaporator is not influenced much by the (A) Boiling point elevations (B) Temperature of the feed (C) Rate of heat transfer (D) Ratio of the weight of the thin liquor to thick liquor

Description : Economy of a multiple effect evaporator is not influenced much by the (A) Boiling point elevations (B) Temperature of the feed (C) Rate of heat transfer (D) Ratio of the weight of the thin liquor to thick liquor

Last Answer : (A) Boiling point elevations

In a multiple effect evaporator, the effect of boiling point elevation is to (A) Reduce the capacity (B) Reduce the economy (C) Increase the economy (D) None of these

Description : In a multiple effect evaporator, the effect of boiling point elevation is to (A) Reduce the capacity (B) Reduce the economy (C) Increase the economy (D) None of these

Last Answer : (A) Reduce the capacity

Economy of an evaporator is influenced by the (A) Steam pressure (B) Feed temperature (C) Number of effect (D) Both (B) & (C)

Description : Economy of an evaporator is influenced by the (A) Steam pressure (B) Feed temperature (C) Number of effect (D) Both (B) & (C)

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

Reason for operating an evaporator in multiple effects is to secure (A) Increased steam economy (B) Decreased steam consumption (C) Both (A) and (B) (D) Increased capacity

Description : Reason for operating an evaporator in multiple effects is to secure (A) Increased steam economy (B) Decreased steam consumption (C) Both (A) and (B) (D) Increased capacity

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

Economy of a multiple effect evaporator depends upon the (A) Heat balance consideration (B) Rate of heat transfer (C) Both (A) and (B) (D) Neither (A) nor (B

Description : Economy of a multiple effect evaporator depends upon the (A) Heat balance consideration (B) Rate of heat transfer (C) Both (A) and (B) (D) Neither (A) nor (B

Last Answer : (A) Heat balance consideration

Vacuum is generally maintained in the vapour space of an evaporator mainly to (A) Get economical temperature difference by using moderate pressure steam (B) Facilitate forward feeding in multiple effect evaporation (C) Concentrate heat sensitive materials (D) Achieve very high concentration of the final product

Description : Vacuum is generally maintained in the vapour space of an evaporator mainly to (A) Get economical temperature difference by using moderate pressure steam (B) Facilitate forward ... (C) Concentrate heat sensitive materials (D) Achieve very high concentration of the final product

Last Answer : (A) Get economical temperature difference by using moderate pressure steam

Which of the following is the most suitable material of construction for evaporator & its tubes for concentrating NaOH solution to 70%? (A) Cast iron (B) Steel (C) Nickel (D) Karbate

Description : Which of the following is the most suitable material of construction for evaporator & its tubes for concentrating NaOH solution to 70%? (A) Cast iron (B) Steel (C) Nickel (D) Karbate

Last Answer : (C) Nickel

Pick out the wrong statement. (A) Economy of a multiple effect evaporator is not influenced by the boiling point elevation (B) Two identical cubes of iron and copper will have the same heat content under the same conditions of temperature (C) Double pipe heat exchangers are mostly used in the field of refrigeration (D) Finned tube heat exchangers are suitable for heating air by steam

Description : Pick out the wrong statement. (A) Economy of a multiple effect evaporator is not influenced by the boiling point elevation (B) Two identical cubes of iron and copper will have the same heat ... in the field of refrigeration (D) Finned tube heat exchangers are suitable for heating air by steam

Last Answer : (B) Two identical cubes of iron and copper will have the same heat content under the same conditions of temperature

Optimum number of effects in a multiple effect evaporator is decided by the (A) Cost benefit analysis (B) Floor area availability (C) Terminal parameters (D) Evaporation capacity required

Description : Optimum number of effects in a multiple effect evaporator is decided by the (A) Cost benefit analysis (B) Floor area availability (C) Terminal parameters (D) Evaporation capacity required

Last Answer : (A) Cost benefit analysis

Optimum number of effects in a multiple effect evaporator is decided by the (A) Cost benefit analysis (B) Floor area availability (C) Terminal parameters (D) Evaporation capacity required

Description : Optimum number of effects in a multiple effect evaporator is decided by the (A) Cost benefit analysis (B) Floor area availability (C) Terminal parameters (D) Evaporation capacity required

Last Answer : (A) Cost benefit analysis

Explain the type of multiple effect evaporator feed arrangement used for handling viscous liquid.

Description : Explain the type of multiple effect evaporator feed arrangement used for handling viscous liquid.

Last Answer : Backward feed arrangement  If the liquid is very viscous, then we have to adopt backward feed arrangement. In this arrangement, the feed solution and vapour flow is in opposite direction. Fresh feed is ... Not very common as it need pump. At low values of feed temperature higher economy.

Steam consumption in kg/hr in case of an evaporator is given by (where, C & E are capacity the economy of the evaporator respectively).(A) C/E (B) E/C (C) CE (D) 1/CE

Description : Steam consumption in kg/hr in case of an evaporator is given by (where, C & E are capacity the economy of the evaporator respectively). (A) C/E (B) E/C (C) CE (D) 1/CE

Last Answer : (A) C/E

Evaporator used for concentrating tomato juice is made of (A) Nickel (B) Brass (C) Stainless steel-glass lined (D) Cast iron-rubber lined

Description : Evaporator used for concentrating tomato juice is made of (A) Nickel (B) Brass (C) Stainless steel-glass lined (D) Cast iron-rubber lined

Last Answer : (C) Stainless steel-glass lined

. An evaporator while concentrating an aqueous solution from 10 to 40% solids evaporates 30000 kg of water. The amount of solids handled by the system in kg is (A) 4000 (B) 9000 (C) 4600 (D) 3000

Description : . An evaporator while concentrating an aqueous solution from 10 to 40% solids evaporates 30000 kg of water. The amount of solids handled by the system in kg is (A) 4000 (B) 9000 (C) 4600 (D) 3000

Last Answer : (A) 4000

Agitated film evaporator is suitable for concentrating __________ liquids. (A) Foaming (B) Viscous (C) Very thin (D) Corrosive

Description : Agitated film evaporator is suitable for concentrating __________ liquids. (A) Foaming (B) Viscous (C) Very thin (D) Corrosive

Last Answer : (B) Viscous

Multiple effect evaporators ar used to (A) Increase the steam economy & decrease the capacity (B) Increase the steam economy & the capacity (C) Decrease the steam economy & the capacity (D) Decrease the steam economy & increase the capacity

Description : Multiple effect evaporators ar used to (A) Increase the steam economy & decrease the capacity (B) Increase the steam economy & the capacity (C) Decrease the steam economy & the capacity (D) Decrease the steam economy & increase the capacity

Last Answer : (B) Increase the steam economy & the capacity

6. In a forward feed multiple effect, the pressure build up will be (A) Least at the inlet of the first effect (B) Least at the outlet of the last effect (C) Highest at the inlet of the last effect (D) Highest at the outlet of the last effect

Description : 6. In a forward feed multiple effect, the pressure build up will be (A) Least at the inlet of the first effect (B) Least at the outlet of the last effect (C) Highest at the inlet of the last effect (D) Highest at the outlet of the last effect

Last Answer : (B) Least at the outlet of the last effect

On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because – (1) metals have higher thermal capacity than plastics (2) plastics have a lower density than metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals

Description : On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because - (1) metals ... metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals

Last Answer : (3) metals are good conductors of heat Explanation: On a chilly day, the room temperature is lower than our body temperature. Since metals have a higher coefficient of thermal conductivity than plastic, they ... from our fingers will flow to the metal cap much more quickly than to the plastic body.

On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because : (1) metals have higher thermal capacity than plastics (2) plastics have a lower density than metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals

Description : On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because : (1) metals ... metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals

Last Answer : metals are good conductors of heat

Pick out the wrong statement. (A) Bubble size increases with the dynamic viscosity of the liquid in case of nucleate pool boiling (B) Thermal conductivity of a dry material is more than that of the damp material (C) Ratio of its capacity to economy equals the steam consumption in kg/hr in an evaporator (D) Vaporisation of organic substances in evaporator mostly causes foam formation

Description : Pick out the wrong statement. (A) Bubble size increases with the dynamic viscosity of the liquid in case of nucleate pool boiling (B) Thermal conductivity of a dry material is more than ... in kg/hr in an evaporator (D) Vaporisation of organic substances in evaporator mostly causes foam formation

Last Answer : (B) Thermal conductivity of a dry material is more than that of the damp material

A perceptron is a ______________ a) Feed-forward neural network b) Backpropagation algorithm c) Backtracking algorithm d) Feed Forward-backward algorithm

Description : A perceptron is a ______________ a) Feed-forward neural network b) Backpropagation algorithm c) Backtracking algorithm d) Feed Forward-backward algorithm

Last Answer : a) Feed-forward neural network

A perceptron is a ——————————–. a) Feed-forward neural network b) Back-propagation algorithm c) Back-tracking algorithm d) Feed Forward-backward algorithm e) Optimal algorithm with Dynamic programming

Description : A perceptron is a ——————————–. a) Feed-forward neural network b) Back-propagation algorithm c) Back-tracking algorithm d) Feed Forward-backward algorithm e) Optimal algorithm with Dynamic programming

Last Answer : a) Feed-forward neural network

The number of kg vaporised per kg of steam fed to the evaporator is defined as (A) Capacity (B) Rate of evaporation (C) Economy (D) Rate of vaporisation

Description : The number of kg vaporised per kg of steam fed to the evaporator is defined as (A) Capacity (B) Rate of evaporation (C) Economy (D) Rate of vaporisation

Last Answer : (C) Economy

Kg of liquid evaporated per hour in an evaporator is defined as its (A) Capacity (B) Economy (C) Steam load (D) None of these

Description : Kg of liquid evaporated per hour in an evaporator is defined as its (A) Capacity (B) Economy (C) Steam load (D) None of these

Last Answer : (A) Capacity

Combustion of pulverised coal compared to the lumpy coal (A) Provides better control of furnace temperature (B) Facilitates combustion with lower excess air (C) Provides higher thermal efficiency & flame temperature (D) All (A), (B) & (C)

Description : Combustion of pulverised coal compared to the lumpy coal (A) Provides better control of furnace temperature (B) Facilitates combustion with lower excess air (C) Provides higher thermal efficiency & flame temperature (D) All (A), (B) & (C)

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

Cold shot cooling is only practical when the feed temperature is __________ than the reaction temperature. (A) Higher (B) Much higher (C) Lower (D) Much lower

Description : Cold shot cooling is only practical when the feed temperature is __________ than the reaction temperature. (A) Higher (B) Much higher (C) Lower (D) Much lower

Last Answer : (D) Much lower

The effect of increasing pressure on the gaseous equilibrium of the reaction2X + 3Y ⇌ 3X + 2Y indicates that(A) Pressure has no effect(B) Backward reaction is favoured(C) Forward reaction is favoured(D) None of the

Description : The effect of increasing pressure on the gaseous equilibrium of the reaction2X + 3Y ⇌ 3X + 2Y indicates that (A) Pressure has no effect (B) Backward reaction is favoured (C) Forward reaction is favoured (D) None of the

Last Answer : (A) Pressure has no effect

Define capacity and economy of evaporator.

Description : Define capacity and economy of evaporator.

Last Answer : The capacity of an evaporator is defined as the number of kilogram of water evaporated per hour. The economy of an evaporator is defined as the number of kilogram of water evaporated per kilogram of steam fed to the evaporator.

The capacity of double-effect evaporator is less than half of the capacity of two single effects, each of which is operating over same terminal temperature difference, when the (A) Solution has an elevation of boiling point (B) Evaporators operate under vacuum (C) Evaporators operate at atmospheric pressure (D) None of these

Description : The capacity of double-effect evaporator is less than half of the capacity of two single effects, each of which is operating over same terminal temperature difference, when the (A) Solution has ... B) Evaporators operate under vacuum (C) Evaporators operate at atmospheric pressure (D) None of these

Last Answer : (A) Solution has an elevation of boiling point

What is the steam economy in case of a single effect evaporator system? (A) 1 (B) > 1 (C) < 1 (D) 0.1

Description : What is the steam economy in case of a single effect evaporator system? (A) 1 (B) > 1 (C) < 1 (D) 0.1

Last Answer : (C) < 1

In a single effect evaporator, the economy is (A) 1 (B) < 1 (C) > 1 (D) None of these

Description : In a single effect evaporator, the economy is (A) 1 (B) < 1 (C) > 1 (D) None of these

Last Answer : (B) < 1

Steam economy in case of a triple effect evaporator will be (A) 1(B) < 1 (C) > 1 (D) Between 0 and 1

Description : Steam economy in case of a triple effect evaporator will be (A) 1 (B) < 1 (C) > 1 (D) Between 0 and 1

Last Answer : (C) > 1

Tubes of multiple effect evaporator used for concentration of sugar cane juice are made of (A) Nickel (B) Copper (C) Stainless steel (D) Brass

Description : Tubes of multiple effect evaporator used for concentration of sugar cane juice are made of (A) Nickel (B) Copper (C) Stainless steel (D) Brass

Last Answer : (B) Copper

Which of the following employs an accessory known as 'drift eliminator'? (A) Multiple effect evaporator (B) Mechanical draft cooling tower (C) Rotary dryer (D) Rotating disc contacto

Description : Which of the following employs an accessory known as 'drift eliminator'? (A) Multiple effect evaporator (B) Mechanical draft cooling tower (C) Rotary dryer (D) Rotating disc contacto

Last Answer : (B) Mechanical draft cooling tower

Small scale evaporation is done in a (A) Heat exchanger (B) Condenser(C) Multiple effect evaporator(D) Steam jacketed kettle

Description : Small scale evaporation is done in a (A) Heat exchanger (B) Condenser (C) Multiple effect evaporator (D) Steam jacketed kettle

Last Answer : (D) Steam jacketed kettle

Black liquor generated during paper manufacture is concentrated in a (A) Single effect evaporator (B) Single effect evaporator followed by a crystalliser (C) Multiple effect evaporator (D) Multiple effect evaporators followed by a crystalliser

Description : Black liquor generated during paper manufacture is concentrated in a (A) Single effect evaporator (B) Single effect evaporator followed by a crystalliser (C) Multiple effect evaporator (D) Multiple effect evaporators followed by a crystalliser

Last Answer : (C) Multiple effect evaporator

Pick out the wrong statement. (A) The value of hydrostatic head increases with increase in vacuum in the effect in a multiple effect evaporator system (B) Entering velocity of the liquid in the tubes of natural circulation evaporators is in the range of 0.3 to 0.9 metre/second (C) Duhring's plot is used for calculating the concentration of solution (D) In a multiple effect evaporation system, the number of effects is limited by the total boiling point rise

Description : Pick out the wrong statement. (A) The value of hydrostatic head increases with increase in vacuum in the effect in a multiple effect evaporator system (B) Entering velocity of the liquid in ... a multiple effect evaporation system, the number of effects is limited by the total boiling point rise

Last Answer : (C) Duhring's plot is used for calculating the concentration of solution

Multiple effect evaporation accounts for (A) Steam economy (B) Lower operating costs(C) Investment economy(D) None of these

Description : Multiple effect evaporation accounts for (A) Steam economy (B) Lower operating costs (C) Investment economy (D) None of these

Last Answer : (A) Steam economy