Which of the following is used for calcination of limestone and dolomite
in industrial practice?
(A) Fluidised bed reactor
(B) Moving bed reactor
(C) Fixed bed reactor
(D) None of these

1 Answer

Answer :

(B) Moving bed reactor

Related questions

Description : Calcination of limestone is not done in a __________ kiln for producing lime. (A) Vertical shaft (B) Rotary (C) Fluidised bed (D) Fixed bed

Last Answer : (D) Fixed bed

Description : Lurgi coal gasifier is a pressurised __________ bed reactor. (A) Moving (B) Fixed (C) Fluidised (D) Entrained

Last Answer : (A) Moving

Description : . Lurgi coal gasifier is a pressurised __________ bed reactor. (A) Moving (B) Fixed (C) Fluidised (D) Entrained

Last Answer : (A) Moving

Description : Rotary kilns are used in the (A) Calcination of limestone & dolomite (B) Cement manufacture (C) Both (A) and (B) (D) Neither (A) nor (B)

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

Description : For high conversion in a highly exothermic solid catalysed reaction, use a __________ bed reactor. (A) Fixed (B) Fluidised bed reactor followed by a fixed (C) Fixed bed reactor followed by a fluidised (D) Fluidised

Last Answer : (B) Fluidised bed reactor followed by a fixed

Description : Which of the following will give maximum gas conversion? (A) Fixed bed reactor (B) Fluidised bed reactor (C) Semi-fluidised bed reactor (D) Plug-flow catalytic reactor

Last Answer : (C) Semi-fluidised bed reactor

Description : Oil is hydrogenated using nickel catalyst in a __________ reactor. (A) Batch (B) Slurry (C) Fluidised bed (D) Fixed bed

Last Answer : (B) Slurry

Description : Thermofor catalytic cracking process is a __________ process. (A) Fixed bed (B) Moving bed (C) Fluidised bed (D) Non-catalytic

Last Answer : (D) Non-catalytic

Description : Platforming is a __________ process. (A) Moving bed (B) Fluidised bed (C) Non-regenerative & fixed bed (D) Regenerative

Last Answer : (C) Non-regenerative & fixed bed

Description : Which of the following is the most widely used cracking process in oil refineries? (A) Dubbs process (B) T.C.C. moving bed process (C) Fluidised bed catalytic cracking process (D) Houdry's fixed bed process

Last Answer : (C) Fluidised bed catalytic cracking process

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 : In a fluidised bed reactor (A) Temperature gradients are very high (B) Temperature is more or less uniform (C) Hot spots are formed (D) Segregation of the solids occurs

Last Answer : (B) Temperature is more or less uniform

Description : Pressure drop in a fluidised bed reactor is __________ that in a similar packed bed reactor. (A) Less than (B) Greater than (C) Same as (D) None of these

Last Answer : (B) Greater than

Description : For a fluidised bed reactor, the most suitable/relevant model is a __________ model. (A) Tank in series (B) Bubbling bed (C) Plug flow (D) None of these

Last Answer : (B) Bubbling bed

Description : Which of the following is the most suitable for very high pressure gas phase reaction? (A) Batch reactor (B) Tubular flow reactor (C) Stirred tank reactor (D) Fluidised bed reactor

Last Answer : (B) Tubular flow reactor

Description : Fluidised bed reactor is characterised by (A) Uniformity of temperature (B) Comparatively smaller equipment (C) Very small pressure drop (D) Absence of continuous catalyst regeneration facility

Last Answer : (A) Uniformity of temperature

Description : In extraction of metal how many of the following ores calcination process is involved . (i) Dolomite (ii) Malachite (iii) Calcite (iv) Copper pyrities

Last Answer : In extraction of metal how many of the following ores calcination process is involved . (i) Dolomite ... Siderite (viii) Iron pyrite (ix) Ar gentite

Description : Calcination of limestone to produce lime is done in a __________ kiln. (A) Tunnel (B) Rotary (C) Vertical shaft (D) Both (B) and (C)

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

Description : Thermal efficiency of a limestone calcination rotary kiln may be around __________ percent. (A) 20 (B) 40 (C) 65 (D) 80

Last Answer : (B) 40

Description : Calcination reaction of limestone (CaCO3 → CaO + CO2 ) goes to completion in the rotary kiln, because (A) CaO is not dissociated (B) CO2 escapes continuously (C) Of high calcination temperature (D) CaO is more stable than CaCO3

Last Answer : (B) CO2 escapes continuously

Description : In case of calcination of limestone, CaCO3 CaO + CO2 , the addition of more of CaO will result in __________ in the concentration of CO2 . (A) No change (B) Increase (C) Decrease (D) Unpredictable from the data

Last Answer : (A) No change

Description : Pick up the correct statement from the following: (A) The heating of a material to redness in contact with air, is known as calcination (B) The property of lime by which it sets or hardens in ... (C) The product that remains after calcination of limestone, is called lime (D) All the above

Last Answer : Answer: Option D

Description : How many of the following are metal carbonates : Dolomite ,Malachite ,Azurite ,Siderite Calamine , Magnasite ,Limestone ,Washing soda ,Cerussite

Last Answer : How many of the following are metal carbonates : Dolomite ,Malachite ,Azurite ,Siderite Calamine , Magnasite ,Limestone ,Washing soda ,Cerussite

Description : All of the following are examples of chemically precipitated sedimentary rock except: w) limestone x) sandstone y) dolomite

Last Answer : ANSWER: X -- SANDSTONE

Description : Which of the following is the most suitable for isothermal operation? (A) Batch reactor (B) Back-mix reactor (C) Plug-flow reactor (D) Fixed bed reactor

Last Answer : (B) Back-mix reactor

Description : For nearly isothermal operation involving large reaction time in a liquid-phase reaction, the most suitable reactor is a __________ reactor. (A) Stirred tank (B) Tubular flow (C) Batch (D) Fixed bed

Last Answer : (A) Stirred tank

Description : Kopper-Totzek coal gasifier (A) Can give ammonia synthesis gas (H2 + N2 ) (B) Is a moving bed reactor (C) Cannot use coking coal (D) Operate at very high pressure

Last Answer : (A) Can give ammonia synthesis gas (H2 + N2 )

Description : Kopper-Totzek coal gasifier (A) Can give ammonia synthesis gas (H2 + N2 ) (B) Is a moving bed reactor (C) Cannot use coking coal (D) Operate at very high pressure

Last Answer : (A) Can give ammonia synthesis gas (H2 + N2 )

Description : . Which of the following is used as a catalyst in fluidised bed catalytic cracking? (A) Silica-magnesia (B) Silica-alumina (C) Bentonite clays (D) All (A), (B) and (C

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

Description : . The most widely used crude topping column in refineries is the__________ column. (A) Bubble-cap (B) Packed bed (C) Fluidised bed (D) Perforated plate

Last Answer : (A) Bubble-cap

Description : Sticky material can be dried in a __________ dryer. (A) Tray (B) Rotary (C) Fluidised bed (D) None of these

Last Answer : (A) Tray

Description : Sand is dried in foundries in a _________drier. (A) Rotary (B) Fluidised bed (C) Vacuum (D) Spray

Last Answer : (B) Fluidised bed

Description : Which of the following is not a batch drier? (A) Truck drier (B) Agitated pan drier (C) Fluidised bed drier (D) Vacuum shelf drier

Last Answer : (C) Fluidised bed drier

Description : Paper industry employs __________ driers. (A) Cylinder (B) Rotary (C) Spray (D) Fluidised bed

Last Answer : (A) Cylinder

Description : Large scale drying of wheat is done in a __________ dryer. (A) Fluidised bed (B) Spouted bed (C) Tray (D) Vacuum rotary

Last Answer : (B) Spouted bed

Description : Which of the following is not applicable to fluidised bed combustion of coal? (A) It cannot burn low grade coal (B) It achieves higher fuel combustion efficiency (C) Less heat transfer surface area is required in boilers (D) None of these

Last Answer : (A) It cannot burn low grade coal

Description : Advantages of fluidised bed combustion are (A) Reduced NOx formation in flue gas (B) Lower furnace operating temperature (C) High heat transfer rate (D) All (A), (B) & (C)

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

Description : Slugging in a fluidised bed can be avoided by using (A) Tall narrow vessel (B) Deep bed of solids (C) Shallow beds of solids and proper choice of particle size (D) Very large particles

Last Answer : (C) Shallow beds of solids and proper choice of particle size

Description : . A 0.5 m high bed made up of a 1 mm dia glass sphere (density 2500 kg/m3 ) is to be fluidised by water (density 1000 kg/m3 ). If at the point of incipient fluidisation, the bed voidage is 40%, the pressure drop across the bed is (A) 4.4 KPa (B) 2.94 KPa (C) 3.7 KPa (D) None of these

Last Answer : (A) 4.4 KPa

Description : Bed pressure drop in an air fluidised bed of catalyst particles (ρp = 200 kg/m3, Dp = 0.05 cm) of 60 cm bed depth and bed porosity of 0.5 expressed in cm of water (manometer) is (A) 90 (B) 60 (C) 45 (D) 30

Last Answer : (B) 60

Description : The uniformity of a gas fluidised bed depends upon the __________ of the solid particles. (A) Size (B) Surface properties (C) Both (A) and (B) (D) Neither (A) nor (B)

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

Description : Minimum porosity for fluidisation is (A) That corresponding to static bed (B) That corresponding to completely fluidised bed (C) The porosity of the bed when true fluidisation begins (D) Less than that of the' static bed

Last Answer : (C) The porosity of the bed when true fluidisation begins

Description : Slugging occurs in a fluidised bed, if the bed is (A) Narrow (B) Deep (C) Both (A) & (B) (D) Neither (A) nor (B)

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

Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system ... What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8

Last Answer : (C) 0.7

Description : Commercial scale production of hydrogen from iron-steam reaction represented by, 3Fe + 3H2O = Fe3O4 + 4H2 , is not practised, as it is (A) A slow reaction (B) A discontinuous reaction (requiring regeneration of ... in development stage (by employing fluidised bed technique) (D) All (A), (B) and (C)

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

Description : Heat transfer by __________ is almost absent in case of fluidised bed drying operation. (A) Radiation (B) Conduction (C) Convection (D) Both (B) & (C)

Last Answer : A) Radiation

Description : Explain the difference between AFBC, BFBC, PFBC and PCFB in regard to fluidised bed technologies.

Last Answer : AFBC (Atmospheric fluidised bed combustion) process consists of forming a bed of inert materials like finely sized ash or ash mixed with sand, limestone (for sulphur removal), and solid fuel particles in ... the bed as bubbles (fluidised bed) and gives the bed the appearance of a boiling liquid.

Description : State some advantages of fluidised bed boilers?

Last Answer : Any type of fuel - solid, liquid (or) gaseous fuel (or) domestic and industrial waste can be used in FBC system. Any type- of combustible matter can be burned by adjusting the factors ... possible. High combustion efficiency. The solid fuel need not be pulverised in fluidised bed boilers.

Description : Write about fluidised bed boilers?

Last Answer : When the high velocity gas is passed through a packed bed of finely divided solid particles, the particles become suspended in the gas stream and the packed bed becomes a fluidised bed. When ... Bed Combustion. The boiler plant using this fluidised bed combustion is known as fluidised bed boilers.

Description : Give the principle and working of Fluidised bed dryer.

Last Answer : Principle: In FBD, good contact between hot air and particles to be dried is obtained which cause rapid drying. Working of Fluidised bed dryer: Two types of FBD are used in pharmaceutical industry. There are ... ranging from 5 kg to 200 kg with an average drying time of about 20-40 min.