Blowdown in a cooling tower
(A) Means discarding a small fraction of circulating water to prevent and
limit the concentration of salt and impurities
(B) Increases the scale forming tendencies of water
(C) Is undesirable
(D) All (A), (B) & (C)
Description : Make up water is supplied during cooling tower operation to compensate for water losses due to (A) Evaporation (B) Blowdown (C) Entrainment (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : Make up water is required in a cooling tower to replace the water lost by (A) Evaporation (B) Drift (C) Blowdown and leakage (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : The ratio of dissolved solids in circulating water to the dissolved solids in makeup water is called a) Liquid gas ratio b) Cycle of concentration c) Cooling tower effectiveness d) None of the above
Last Answer : Cycle of concentration
Description : The ratio of dissolved solids in circulating water to dissolved solids in makeup water is called. • Liquid gas ratio • Cycle of concentration • Cooling tower effectiveness • None of the above
Description : Drift in a cooling tower is (A) The water entrained by the circulating air (B) Dependent on the water lost by evaporation (C) Desirable (D) All (A), (B) & (C)
Last Answer : (A) The water entrained by the circulating air
Description : Heat load in a cooling tower (A) Means the amount of heat thrown away (KCal/hr.) by the cooling tower (B) Is equal to the number of kg, of water circulated times the cooling range (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : Forced circulation evaporators are useful for the concentration of viscous, salting and scale forming liquors. Which of the following is a forced circulation evaporator? (A) Long vertical evaporator (B) Horizontal tube evaporator (C) Agitated film evaporator (D) Calandria vertical tube evaporator
Last Answer : (C) Agitated film evaporator
Description : Which of the following is an undesirable property in a tower packing? (A) Large surface per unit volume (B) Large free cross-section (C) Low weight per unit volume (D) Large weight of liquid retained
Last Answer : (D) Large weight of liquid retained
Description : Water entrained by circulating air in cooling towers is termed as (A) Drift (B) Blow down (C) Vapor load (D) None of these
Last Answer : (A) Drift
Description : Addition of suitable impurities into semiconductor, is called – (1) Doping (2) Mixing (3) Forming (4) Diluting
Last Answer : (1) Doping Explanation: In semiconductor production, doping refers to the introduction of impurities into an extremely pure intrinsic semiconductor for the purpose of modulating its electrical properties. ... type of semiconductor and the properties that it needs to have for its intended purpose.
Description : Addition of suitable impurities into semiconductor, is called (1) Doping (2) Mixing (3) Forming (4) Diluting
Last Answer : Doping
Description : H2S is being absorbed in a gas absorber unit. The height of the transfer unit based on the overall mass transfer coefficient on the gas side is 0.4 m. The equilibrium data is given by, y = 1.5 x. The bulk concentration of H2S ... by, y = 5x + 0.001 is (A) 2.0 (B) 1.56 (C) 1.0
Last Answer : (A) 2.0
Description : Pick out the wrong statement. (A) Linear polymers are formed from bifunctional groups only and are normally thermoplastic (B) Cross-linked branched chain polymers are either elastometric or ... (D) Dibasic acids reacts with dihydric alcohols to give polyesters using addition polymerisation reaction
Last Answer : D) Dibasic acids reacts with dihydric alcohols to give polyesters using addition polymerisation reaction
Description : Explosion limit of blast furnace gas is 37 to 71% gas in gas-air mixture. It means that the blast furnace gas will explode when burnt in a confined space, if its concentration in the gas-air mixture is __________ percent. (A) < 37% (B) > 71% (C) In between 37 & 71% (D) None of these
Last Answer : (C) In between 37 & 71%
Description : Write various advantages of using high mast tower lighting viz a vIz Sodium lamps in circulating areas?
Last Answer : Ans. (i) Better illumination (ii) Vide area illumination (iii)where mass public movement (iv) Where loading & unloading of materials (v) At goods coaches & passenger coaches formation, checking and maintenance.
Description : Sweetening of petroleum product means the removal of (A) Sulphur & its compounds (B) Water (C) Organic impurities (D) Wax
Last Answer : (A) Sulphur & its compounds
Description : In a forced draft cooling tower, water is cooled from 95 to 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the (A) Range is 15°F (B) Approach is 10°F (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : Common applications of Cooling towers include a. Cooling the circulating water used in oil refineries b. petrochemical and other chemical plants c. thermal power stations d. All of the above.
Last Answer : All of the above.
Description : Use of natural draft cooling tower is practised, when the air has low (A) Humidity (B) Temperature (C) Both 'a' & 'b' (D) Neither 'a' nor 'b'
Last Answer : (C) Both 'a' & 'b
Description : Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is mainly caused due to the turbulence created by blade passage through air. It can be reduced by use of a slower fan (A) With greater ... (B) Of increased diameter (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : Pick out the wrong statement about the machinability of metals. Machinability of a metal (A) Decreases with increase in strain hardening tendencies (B) Decreases with increase in hardness, in general (C) Depend on the composition, microstructure and physical & mechanical
Last Answer : Option C
Description : cooling is the process of dissipating the armature and field winding losses to a cooling medium circulating within the winding insulation wall (a) Direct (b) Indirect (c) Conventional (d) Any ofthe above
Last Answer : (a) Direct
Description : Which of the following impurities in feed water for high pressure boiler is the most detrimental? (A) Silica (B) Dissolved oxygen (C) Suspended salt (D) Dissolved salt
Last Answer : (A) Silica
Description : Semibatch reactor is preferred, when a/an (A) A highly exothermic reaction is to be controlled (B) Undesirable side reaction (at high concentration of one of the reactants) is to be avoided (C) A gas is to be reacted with liquid (e.g. hydrogenation of fat) (D) All (A), (B), and (C
Last Answer : (D) All (A), (B), and (C
Description : Function of thinner in a paint is to (A) Accelerate the oxidation of oil (B) Prevent gelling of the paint (C) Suspend pigments & dissolve film forming materials (D) Form a protective film
Last Answer : (C) Suspend pigments & dissolve film forming materials
Description : Is the intentional discarding of a valuable engagement ring onto the ground in a public place littering?
Last Answer : answer:Litter is officially defined as: objects strewn or scattered about. It has nothing to do with the value of the item. If it’s discarded, it’s litter.
Description : Perception is a three-step process that involves 1. motivation, personality and attitudes 2. collecting, eliminating and organizing information inputs 3. selecting, organizing and interpreting information inputs 4. anticipating, classifying and discarding information inputs 5. none of these
Last Answer : selecting, organizing and interpreting information inputs
Description : What is BlowDown Valve?
Last Answer : Answer: Refers to a plug type disc globe valve used for removing sludge and sedimentary matter from the bottom of boiler drums, vessels, driplegs etc.
Description : Perception is a three-step process that involves A)motivation, personality, and attitudes. B)collecting, eliminating, and organising information inputs. C)selecting, organising, and interpreting information inputs. D)anticipating, classifying, and discarding information inputs.
Last Answer : C)selecting, organising, and interpreting information inputs.
Description : _______ cooling towers use a process similar to the one found in small evaporative cooling units. a. Hyperboloid b. Tower c. Condensate loop d. None
Last Answer : a. Hyperboloid
Description : Which cooling Towers use a process similar to the one found in small evaporation active cooling units a) hyperbolic b) Tower c) condensate loop d) none of these
Last Answer : a) hyperbolic
Description : Design of hyperbolic cooling tower standard for all cooling tower a) Mechanical draft b) Natural draft c) Both a & b d) Neither a & b
Last Answer : b) Natural draft
Description : The circulating concentration of ACTH in plasma is (A) 0.05 mµ/100 ml (B) 0.1–2.0 mµ/100 ml (C) 2.5–3.5 mµ/100 ml (D) 3.0–5.0 mµ/100 ml
Last Answer : Answer : B
Description : Finasteride acts by: A. Blocking testosterone receptors in the prostate gland B. Reducing testosterone secretion from testes C. Reducing LH secretion from pituitary D. Lowering circulating as well as prostatic dihydrotestosterone concentration
Last Answer : D. Lowering circulating as well as prostatic dihydrotestosterone concentration
Description : Lower temperature and large excess of ammonia in urea melt (A) Increases biuret formation (B) Decreases biuret formation (C) Is undesirable (D) Does not effect biuret formation
Last Answer : (B) Decreases biuret formation
Description : Threshold limit value (TLV) means maximum permissible/acceptable concentration. TLV of phosgene in air is about __________ ppm (parts per million). (A) 0.002 (B) 0.2 (C) 1.2 (D) 4.8
Last Answer : (B) 0.2
Description : The presence of impurities in iron (A) Increases its melting point (B) Does not affect its melting point (C) Decreases its melting point (D) Makes it malleable
Last Answer : (C) Decreases its melting point
Description : As the impurities are oxidised, the melting point of iron (A) Decreases (B) Remains unchanged (C) Increases (D) May increase or decrease; unpredictable
Last Answer : (C) Increases
Description : (4) sodium chloride contains hygroscopic impurities like magnesium chloride Explanation: Table salt is refined salt, which contains about 97 to 99 percent sodium chloride. It usually contains substances that ... of salt it become wet in rainy season as the salt absorbs moisture from environment.
Last Answer : Which of the following could be used as fuel in propellant or rockets? (1) Liquid Hydrogen + Liquid Nitrogen (2) Liquid Oxygen + Liquid Argon (3) Liquid Nitrogen + Liquid Oxygen (4) Liquid Hydrogen + Liquid Oxygen
Description : Table salt gets moist during rainy season because (1) sodium chloride is hygroscopic (2) sodium chloride is deliquescent (3) sodium chloride contains some quantity of sodium iodide (4) sodium chloride contains hygroscopic impurities like magnesium chloride
Last Answer : sodium chloride contains hygroscopic impurities like magnesium chloride
Description : Stresses encountered in the metal forming processes are less than the __________ of the material. (A) Fracture strength (B) Yield strength (C) Elastic limit (D) Limit of proportionality
Last Answer : Option A
Description : The term "cooling range" in a cooling tower refers to the difference in the temperature of (A) Cold water leaving the tower and the wet bulb temperature of the surrounding air (B) Hot water entering the ... air (C) Hot water entering the tower and the cooled water leaving the tower (D) None of these
Last Answer : (C) Hot water entering the tower and the cooled water leaving the tower
Description : Can a cooling tower cool water below the wet bulb temperature of inlet air? (A) Yes (B) No (C) Yes; but height of cooling tower will be prohibitively high (D) Yes; but the air flow rate should be excessively high
Last Answer : (B) No
Description : Pick out the wrong statement. (A) Different solids have different equilibrium moisture curves (B) Total condenser or reboiler is considered equivalent to one theoretical plate in McCabe-Thiele method of ... (D) Even a forced draft cooling tower cannot cool water below the wet bulb temperature
Last Answer : (C) Heat removal load on cooler remains constant, even with increase of the reflux ratio in a distillation column
Description : The term "approach" in a cooling tower refers to the difference in the temperature of the (A) Cold water leaving the tower and the wet bulb temperature of the surrounding air (B ... (C) Hot water entering and the cooled water leaving the cooling tower (D) None of these
Last Answer : (A) Cold water leaving the tower and the wet bulb temperature of the surrounding air
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
Description : In a cooling tower, water becomes cool by (A) Loosing sensible heat (B) Heat transfer to surroundings (C) Vaporisation due to heat loss to air (D) Loosing latent heat
Last Answer : (A) Loosing sensible heat
Description : The minimum temperature to which the water can be cooled in a cooling tower is the __________ temperature of air. (A) Ambient (B) Dry bulb (C) Dew point (D) Wet bulb
Last Answer : C) 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