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

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

by

1 Answer

Answer :

(C) Economy

by

Related questions

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

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

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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

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Evaporation of 1kg of water from a solution in a single effect evaporator requires about __________ kg of steam. (A) 0.4 - 0.6 (B) 1-1.3 (C) 1.8-2 (D) 2 - 2.4

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It is desired to concentrate a 20% salt solution (20 kg of salt in 100 kg of solution) to a 30% salt solution in an evaporator. Consider a feed of 300 kg/min at 30°C. The boiling point of the solution is 110°C, the latent heat of vaporisation is 2100 kJ/kg and the specific heat of the solution is 4 kJ/kg.K. The rate at which the heat has to be supplied in (kJ/min) to the evaporator is (A) 3.06 × 10 5 (B) 6.12 × 10 5 (C) 7.24 × 10 5 (D) 9.08 × 10

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Last Answer : (A) 3.06 × 10

The amount of water evaporated in kg per kg of fuel burnt in a boiler is called the __________ of a boiler. (A) Evaporative capacity (B) Evaporation efficiency (C) Thermal efficiency (D) Steam load

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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

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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

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

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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

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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

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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

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The critical pressure at which the latent heat of vaporisation of steam becomes zero is __________ Kg/cm2. (A) 273.15 (B) 225.65 (C) 100.03 (D) 373.15

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In case of steam distillation, the steam leaving the liquid is not completely saturated with distillate vapour, because(A) Temperature is less(B) Total pressure is less(C) Mixing of steam with the material being vaporised is not so intimate asto result in equilibrium condition(D) Saturated steam is used for steam distillation

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

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

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

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Steam at 1000C causes more severe burns than water at 100° C because (1) steam has no specific heat capacity (2) steam has latent heat of vaporisation (3) water has no specific heat capacity (4) water has latent heat of fusion

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In case of evaporators, liquid entrainment results primarily due to (A) High vacuum in the evaporator (B) High evaporation rate (C) Foaming of the solution (D) High heat transfer rate

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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

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Heat sensitive materials with very high latent heat of vaporisation may be economically separated using (A) Liquid extraction (B) Distillation (C) Evaporation (D) Absorption

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Evaporation by thermo compression results in the (A) Saving of steam (B) Realisation of multiple effect economy in a single effect (C) Both (A) and (B) (D) None of these

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Gibbs free energy per mole for a pure substance is equal to the (A) Latent heat of vaporisation (B) Chemical potential (C) Molal boiling point (D) Heat capacity

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