The separation of liquid droplets from the vapor is done by a/an
__________, in the evaporators.
(A) Steam ejector
(B) Entrainment separator
(C) Compressor
(D) Vacuum pump
Description : Pick out the wrong statement: (A) The capacity of an evaporator is reduced by the boiling point elevation (B) Corrosive liquid is normally passed through the tubes in a ... recompression evaporator (D) Heat sensitive materials should be concentrated in high pressure evaporators
Last Answer : (D) Heat sensitive materials should be concentrated in high pressure evaporators
Description : 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
Last Answer : (C) Foaming of the solution
Description : In most of the vacuum crystalliser, vacuum is generally produced by means of a (A) Suction pump (B) Compressed air jet (C) Steam jet ejector with a barometric condenser (D) None of these
Last Answer : (C) Steam jet ejector with a barometric condenser
Description : For the production of very high vacuum, a __________ pump is normally used. (A) Diffusion (B) Centrifugal (C) Jet ejector (D) Piston
Last Answer : (A) Diffusion
Description : The steam ejector is used to (A) Remove condensate from the steam pipelines (B) Create vacuum (C) Superheat the steam (D) None of these
Last Answer : (B) Create vacuum
Description : Pick out the wrong statement about cavitation. (A) Sudden reduction of pressure in a fluid flow system caused by flow separation, vortex formation or abrupt closing of valve leads to cavitation ... (D) Large scale cavitation cannot damage pipeline, restrict fluid flow and damage steam turbine blades
Last Answer : (D) Large scale cavitation cannot damage pipeline, restrict fluid flow and damage steam turbine blades
Description : How do you design a vapor-liquid separator or a flash drum?
Last Answer : The size of a vapor-liquid separator should be dictated by the anticipated flow rate of vapor and liquid from the vessel. The following sizing methodology is based on the assumption that those flow ... much liquid flow you expect, the liquid outlet line should probably have a level control valve.
Description : A compressor that takes suction at a pressure below atmospheric and discharge against atmospheric pressure is called a __________ pump. (A) Sump (B) Volute (C) Vacuum (D) Submerged
Last Answer : (C) Vacuum
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
Description : Where is water steam separator drum located in Lamont boiler ? a. Inside of the boiler b. Right above the furnace c. Before the feed water pump d. Outside the boiler
Last Answer : d. Outside the boiler
Description : The non-clog pump which permits solid matter to pass out with the liquid sewage, is A. Centrifugal pump B. Reciprocating pump C. Pneumatic ejector D. None of these
Last Answer : ANS: A
Description : Which of the following pumps in used to pump sewage solids with liquid sewage without clogging the pump is? A. Centrifugal pump B. Pneumatic ejector C. Reciprocating pump D. None of these
Description : When water vapor forms liquid water droplets on a window in the early morning and example?
Last Answer : Need answer
Description : Pick out the wrong statement. (A) Critical moisture content is not a property of the material itself (B) A sharp increase in pressure drop gives an indication of the flooding in a ... unity (D) Dehydration of ethyl alcohol is most economically done by molecular distillation at very high vacuum
Last Answer : (D) Dehydration of ethyl alcohol is most economically done by molecular distillation at very high vacuum
Description : Which of the following has the maximum compression ratio? (A) Blower (B) Compressor (C) Vacuum pump (D) Fan
Last Answer : (C) Vacuum pump
Description : Plate efficiency in a distillation column is reduced due to the __________ of liquid. (A) Entrainment (B) Foaming (C) Weeping & dumping (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : In centrifugal pump operation, the cavitation can be eliminated by maintaining suction pressure __________ the vapor pressure of the liquid at the suction temperature. (A) Lower than (B) Higher than (C) Equal to (D) None of these
Last Answer : (B) Higher than
Description : On moving the feed line (q-line) from saturated liquid feed (vertical position) to saturated vapor feed (horizontal feed), if the slope of both the operating lines are to be increased, then it will result in (A) Greater degree of separation with a fixed number of trays (B) Increased reboiler load
Last Answer : (C) Increased reflux ratio
Description : The type of liquor circulation system to be ' employed in evaporators (viz. natural or forced circulation) is determined mainly by the __________ of the liquid. (A) Viscosity (B) Density (C) Thermal conductivity (D) Corrosive nature
Last Answer : (A) Viscosity
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
Description : Flue gas from the heating chamber of byproduct coke ovens is removed by (A) Forced draft fan (B) Induced draft fan (C) Steam ejector (D) Natural draft
Last Answer : (D) Natural draft
Description : In the cyclone separator used for separation of dust from dust laden gas, the gas (A) Enters the cyclone from the top (B) Is admitted tangentially at high velocity (C) Develops a helical motion inside the chamber (D) Both (B) and (C
Last Answer : (D) Both (B) and (C
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
Description : It is not preferable to use superheated steam in evaporators, because of its very (A) High temperature (B) High pressure (C) Low film co-efficient (D) None of these
Last Answer : (C) Low film co-efficient
Description : The purpose of providing a 'catchall' in the vapor line of an evaporator is to (A) Create vacuum (B) Regulate the vapor flow (C) Vent the non-condensable gases (D) Arrest the entrained liquid
Last Answer : (D) Arrest the entrained liquid
Description : The disintegrating pump in which solid matter is broken up before passing out, is A. Centrifugal pump B. Reciprocating pump C. Pneumatic ejector D. None of these
Description : Q No: 131 The most widely used pump for lifting sewage is A. Centrifugal pump B. Reciprocating pump C. Pneumatic ejector D. Air pressure pump
Description : The net positive suction head (NPSH) of a centrifugal pump is defined as the sum of the velocity head and the pressure head at the (A) Discharge (B) Suction (C) Suction minus vapor ... of the liquid at suction temperature (D) Discharge minus vapor pressure of the liquid at the discharge temperature
Last Answer : (C) Suction minus vapor pressure of the liquid at suction temperature
Description : Low-temperature ____ evaporators are used for heat-sensitive foods. a. ultrafiltration c. vacuum b. osmosis d. drum
Last Answer : c. vacuum
Description : Plate efficiency (A) Is a function of the mass transfer between liquid and vapour (B) Increases due to foaming (C) Increases due to liquid entrainment (D) Increases due to weeping and dumping of liquid
Last Answer : (A) Is a function of the mass transfer between liquid and vapour
Description : To get high tray efficiency (A) Interfacial surface between liquid and gas phase should be large (B) Time of contact between the two phases should be less (C) Gas velocity should be very low (D) Liquid entrainment should be severe
Last Answer : (A) Interfacial surface between liquid and gas phase should be large
Description : In what form do Water vapor droplets form clouds and Earth's gravity pulls the moisture to the surface?
Last Answer : The moisture drops to the earth as some form of precipitation(rain, snow, sleet, hail).
Description : What Water vapor droplets form clouds and Earth's gravity pulls the moisture to the surface in the form of?
Last Answer : rain
Description : Pick out the wrong statement. (A) The controlling resistance in case of heating of air by condensing steam is in the air film (B) The log mean temperature difference (LMTD) for ... a pure fluid at a given pressure from liquid to vapor or vice-versa occurs at saturation temperature
Last Answer : (C) In case of a 1 - 2 shell and tube heat exchanger, the LMTD correction factor value increases sharply, when a temperature cross occurs
Description : The actual temperature drop across the heating surface of an evaporator depends on the (A) Liquid depth over the heating surface (B) Solution being evaporated (C) Pressure difference between the steam chest and the vapor space above the boiling liquid (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Tabular bowl centrifuges as compared to disk bowl centrifuges (A) Operate at higher speed (B) Employ bowl of larger diameter (C) Can’t be operated under pressure/vacuum (D) Can’t be used for separation of fine suspended solids from a liquid
Last Answer : (A) Operate at higher speed
Description : Which of the following is the most suitable filter for separation ofabrasive solids suspended in a corrosive liquid? (A) Sand bed filter (B) Plate and frame filter press (C) Vacuum filter (D) Batch basket centrifuge
Last Answer : (C) Vacuum filter
Description : Out of two equilibrium curves, first one lies above the diagonal and the second lies below the diagonal in the x-y plot. It means that separation by distillation is (A) Not possible in the second ... (C) More readily done in the second case compared to first one (D) None of these
Last Answer : (C) More readily done in the second case compared to first one
Description : Pick out the wrong statement: (A) Reboiler is not used in open steam distillation (B) The separation of solutes of different molecular sizes in a liquid solution by use of a ... is used for calculating theoretical number of plates in a distillation column at normal operating reflux condition
Last Answer : (D) Fenske-Underwood equation is used for calculating theoretical number of plates in a distillation column at normal operating reflux condition
Description : Priming of a centrifugal pump is done to (A) Increase the mass flow rate of fluid (B) Develop effective pressure rise by the pump (C) Avoid chances of separation inside the impeller (D) None of these
Last Answer : (C) Avoid chances of separation inside the impeller
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
Description : Condensate is the liquid formed when steam passes from the ________ to the ______ state. a. Vapor, solid b. Solid, liquid c. Vapor, liquid d. None
Last Answer : c. Vapor, liquid
Description : A vessel with a volume of cubic meter contains liquid water and water vapor ion equilibrium at 600 kPa. The liquid water has mass of1kg. Using the steam table, calculate the mass of the water vapor. A. 0.99kg B. 1.57 kg C ... / kg vg = 0.3157 m^3 / kg Vtot = mƒ vƒ + mg vg mg = (tot-mƒ vƒ) / vg
Last Answer : 3.16 kg
Description : A 10m^3 vessel initially contains 5 m^3 of liquid water and 5 m^3 of saturated water vapor at 100 kPa. Calculate the internal energy of the system using the steam table. A. 5 x10^5 kJ B. 8x10^5 kJ C. 1 ... 3 kJ/kg ug= 2506kJ/kg formula: Mvap = V vap/vg M liq = Vliq/ vƒ u =uƒM liq + ug M vap
Last Answer : 2 x10^6 kJ
Description : Dryness factor of steam is defined as the ratio of the mass of vapor in the mixture to the mass of the mixture. Dryness factor of steam is measured by a __________ calorimeter. (A) Bomb (B) Throttling (C) Junker's (D) Boy's
Last Answer : Option B
Description : For separation of sugar solution from settled out mud, we use a __________ filter. (A) Sparkler (B) Plate and frame (C) Centrifugal (D) Rotary drum vacuum
Last Answer : (C) Centrifugal
Description : Commercial production of hydrogen for the manufacture of nitrogenous fertilisers is done by (A) Steam reforming of naphtha and cracking of natural gas (B) Electrolysis of water (C) Cryogenic separation of hydrogen from coke oven gas (D) All (A), (B) and (C)
Description : Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system? (A) Expansion valve (B) Condenser (C) Refrigerator (D) Compressor
Last Answer : (D) Compressor
Description : Pumping of a corrosive liquid is generally preferred to be done by a __________ pump, as it can be made of a variety of materials including plastics. (A) Piston (B) Gear (C) Positive displacement (D) Sump
Last Answer : (B) Gear