Which of the following accessories is provided in the vapor line of an
evaporator for removing the entrained liquid?
(A) Bleed point
(B) Vent
(C) Catchall
(D) Baffle
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 : 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 : 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 : 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 : The purpose of providing bleed points in the evaporator is to (A) Admit the feed (B) Remove the product (C) Facilitate removal of non-condensable gases (D) Create vacuum
Last Answer : (C) Facilitate removal of non-condensable gases
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
Description : The vent valve provided in a liquid handling centrifugal pump is (A) Generally a needle valve (B) Used to release any gases that might be vapour locking the pump (C) Helpful in easy removal of samples (D) All (A), (B) and (C)
Description : In septic tanks, A. Free board of 0.3 m may be provided B. The baffles or tees are extended up to top level of scum C. The clear space between the baffle top and covering slab is about 7.5 cm D. All the above
Last Answer : ANS: D
Description : Bottom openings 15 cm × 15 cm in the standing baffle wall are provided A. 15 cm c/c B. 22.5 cm c/c C. 30 cm c/c D. 50 cm c/c
Last Answer : ANS: B
Description : Vent pipes are provided in a condenser to (A) Remove non-condensable gases (B) Purge the condenser (C) Facilitate easy cleaning of tubes (D) None of these
Last Answer : (A) Remove non-condensable gases
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 : Pick up the incorrect statement from the following: A. Septic tanks are horizontal continuous flow type of sedimentation tanks B. Septic tanks are generally provided a detention period of 12 to 36 hours C ... covered and high vent shafts are provided for the escape of foul gases D. None of these
Description : As the reflux ratio in a distillation column is increased from the minimum, the (A) Slope of the operating line in stripping section decreases (B) Number of plates decreases very slowly first ... decreases and then increases (D) Liquid flow increases while the vapor flow decreases for a system
Last Answer : (C) Total cost first decreases and then increases
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 : __________ is the temperature at which a gas-vapor mixture becomes saturated, when cooled at constant total pressure out of contact with a liquid. (A) Dew point (B) Bubble point (C) Dry bulb temperature (D) Wet bulb temperature
Last Answer : (A) Dew point
Description : In an operating distillation column, the (A) Vapors and liquids are at their dew point and bubble point respectively (B) Driving force for the liquid flow is its specific weight (C) Driving force for ... bottom to the top of the column (D) Highest temperature is encountered at the top of the column
Last Answer : (C) Driving force for the vapor flow is the pressure drop, as the pressure decreases gradually from the bottom to the top of the column
Description : Leidenfrost point is a term concerned with the (A) Condensation of the saturated vapor on a cold surface (B) Concentration of a corrosive solution by evaporation (C) Heat transfer between two highly viscous liquids (D) Boiling of a liquid on a hot surface
Last Answer : (D) Boiling of a liquid on a hot surface
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 : Kopper-Totzek coal gasifier (installed in a coal based nitrogeneous fertiliser plant) employs a/an __________ bed gasifier. (A) Entrained (B) Moving (C) Fixed (D) Fluidised
Last Answer : (A) Entrained
Description : Lurgi coal gasifier is a pressurised __________ bed reactor. (A) Moving (B) Fixed (C) Fluidised (D) Entrained
Last Answer : (A) Moving
Description : In continuous fluidisation (A) Solids are completely entrained (B) The pressure drop is less than that for batch fluidisation (C) There is no entrainment of solids (D) Velocity of the fluid is very small
Last Answer : (A) Solids are completely entrained
Description : . Lurgi coal gasifier is a pressurised __________ bed reactor. (A) Moving (B) Fixed (C) Fluidised (D) Entrained
Description : The actual temperature drop across the heating surface in an evaporator depends on the (A) Feed (B) Depth of liquid over heating surface (C) Pressure difference between steam chest and vapour space (D) All (A), (B) and (C)
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 : 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
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
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
Description : The equipment used in the extraction of highly corrosive radioactive liquids is (A) Pulse column (B) Spray column (C) Mixer settler (D) Baffle tower
Last Answer : (A) Pulse column
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
Description : In case of a multipass shell and tube heat exchanger, providing a baffle on the shell side __________ the heat transfer rate. (A) Increases (B) Decreases (C) Does not affect (D) May increase or decrease, depends on the type of baffle
Last Answer : (A) Increases
Description : If the baffle spacing in a shell and tube heat exchanger increases, then the Reynolds number of the shell side fluid (A) Remains unchanged (B) Increases (C) Increases or decreases depending on number of shell passes (D) Decreases
Last Answer : (D) Decreases
Description : Baffle spacing (A) Is not the same as baffle pitch (B) Should be less than one fifth the diameter of the shell (C) Should be less than the inside diameter of the shell (D) None of these
Last Answer : (C) Should be less than the inside diameter of the shell
Description : Shell side pressure drop in a shell and tube heat exchanger does not depend upon the (A) Baffle spacing & shell diameter (B) Tube diameter & pitch (C) Viscosity, density & mass velocity of shell side fluid (D) None of these
Description : In case of a shell and tube heat exchanger, the minimum and maximum baffle spacing is respectively (where, D = inside diameter of the shell) (A) D/5 and D (B) D/2 and 2 D (C) D/4 and 2 D (D) D and 2 D
Last Answer : (A) D/5 and D
Description : Minimum recommended baffle spacing in a shell and tube heat exchanger is about (where, D = shell diameter). (A) 0.2 D (B) 0.5 D (C) 0.66 D (D) 0.80 D
Last Answer : (A) 0.2 D
Description : Extremely large or small volumes of fluids are generally best routed through the shell side of a shell and tube heat exchanger, because of the (A) Less corrosion problems (B) Flexibility possible in the baffle arrangement (C) Low pressure drop (D) High heat transfer co-efficient
Last Answer : (B) Flexibility possible in the baffle arrangement
Description : In a shell and tube heat exchanger, putting a longitudinal baffle across the shell, forces the shell side fluid to pass __________ through the heat exchanger. (A) Once (B) Twice (C) Thrice (D) Four times
Last Answer : (B) Twice
Description : __________________ represents the highest pressure and highest temperature at which liquid and vapor can coexist in equilibrium. a) Critical Point b) Boiling Point c) Quality Point d) None of the above
Last Answer : Critical Point
Description : What refers to the point at which the saturated liquid and saturated vapor states are the same or identical? A. Triple point B. Inflection point C. Maximum point D. Critical point
Last Answer : Maximum point
Description : Dew point of an air-water vapor mixture (A) Decreases with decrease in pressure (B) At constant humidity & total pressure is fixed (C) Corresponding to any point on the humidity chart is obtained by projecting a ... to the temperature axis and to the saturation curve (D) All 'a', 'b' & 'c'
Last Answer : (D) All 'a', 'b' & 'c'
Description : If the voids of a soil mass are full of air only, the soil is termed as (A) Air entrained soil (B) Partially saturated soil (C) Dry soil (D) Dehydrated soil
Last Answer : Option C
Description : While designing an air entrained concrete (A) Water cement ratio is reduced (B) Proportion of aggregates is reduced (C) An allowance for the entrained air is made (D) All the above
Last Answer : (D) All the above
Description : The entrained air in concrete (A) Increases workability (B) Decreases workability (C) Decreases resistance to weathering (D) Increases stress
Last Answer : Answer: Option A
Description : A concrete using an air entrained cement (A) Has strength less than 10% to 15% (B) Has more resistance to weathering (C) Is more plastic and workable (D) Is free from segregation and bleeding
Last Answer : Answer: Option C
Description : The entrained concrete is used in lining walls and roofs for making (A) Heat insulated (B) Sound insulated (C) Neither (a) nor (b) (D) Both (a) and (b)
Last Answer : Answer: Option D
Description : The entrained air in concrete [ A ] Increases the strength [ B ] Decreases the resistance to weathering [ C ] Increases the workability [ D ] Decreases the workability
Last Answer : [ C ] Increases the workability
Description : Choose the wrong statement (a) Temperature of medium being cooled must be below that of the evaporator (b) Refrigerant leaves the condenser as liquid (c) All solar thermally operated absorption systems are capable only of intermittent operation (d) frost on evaporator reduces heat transfer
Last Answer : Ans: a
Description : In vapour compression refrigeration system, refrigerant occurs as liquid between (a) condenser and expansion valve (b) compressor and evaporator (c) expansion valve and evaporator (d) compressor and condenser
Last Answer : Ans: c
Description : In a flooded evaporator refrigerator, an accumulator at suction of compressor is used to (a) collect liquid refrigerant and prevent it from going to compressor (b) detect liquid in vapour (c) superheat the vapour (d) increase refrigeration effect
Description : Condensing temperature in a refrigerator is the temperature (a) of cooling medium (b) of freezing zone (c) of evaporator (d) at which refrigerant gas becomes liquid
Last Answer : Ans: d