Description : In high temperature carbonisation (as compared to low temperature carbonisation) of coal (A) Coke oven gas yield is more (B) Tar yield is less but free carbon in tar is more (C) Calorific value of coke oven gas is less (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Coke oven gas produced by high temperature carbonisation of coal (as compared to that produced by low temperature carbonisation), has (A) Higher calorific value (B) Lower hydrogen content (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (D) Neither (A) nor (B)
Description : In low temperature carbonisation of coal as compared to high temperature carbonisation __________ produced is less. (A) Difference in gross & net calorific value of the coke oven gas (B) Free carbon content in tar (C) Yield percentage of coke (D) Yield of ammonia present in coke oven gas
Last Answer : (A) Difference in gross & net calorific value of the coke oven gas
Description : In high temperature carbonisation of coal compared to low temperature carbonisation (A) Yield of ammonia is less (B) Aromatic content of tar is low (C) H2 content in the coke oven gas is more (D) Calorific value of the coke oven gas is lower
Last Answer : (C) H2 content in the coke oven gas is more
Description : With increase in the temperature of carbonisation of coal (A) Hydrogen content of coke oven gas increases due to cracking ofhydrocarbons (B) Methane content in the coke oven gas decreases and carbon monoxide content increases ( ... compensated by increase in CO & H2 content (D) All (A), (B) and (C)
Description : Calorific value of coke even gas produced by low temperature carbonisation of coal is about __________ Kcal/Nm3 . (A) 4000 (B) 2500 (C) 6500 (D) 10000
Last Answer : (C) 6500
Description : Pick out the wrong statement: (A) Carburetted water gas is also called blue gas (B) Coals are divided in four species according to their carbon content in Seylor's classification (C) Carbonisation time ... and net calorific value of a fuel is the same, if it does not contain hydrogen or hydrocarbons
Last Answer : (A) Carburetted water gas is also called blue gas
Description : High temperature carbonisation of coal produces (A) Inferior coke compared to low temperature carbonisation (B) Less of gases compared to liquid products (C) Large quantity of tar compared to low temperature carbonisation (D) None of these
Last Answer : (D) None of these
Description : High temperature carbonisation of coal produces (A) Inferior coke compared to low temperature carbonisation (B) Less of gases compared to liquid products (C) Larger quantity of tar compared to low temperature carbonisation (D) None of these
Description : Yield of coke oven gas in low temperature carbonisation of coal is about __________ Nm3 /ton of dry coal. (A) 60 (B) 160 (C) 500 (D) 750
Last Answer : (B) 160
Description : In low temperature carbonisation of coal, the (A) Yield of coke oven gas is 290 Nm3 /ton dry coal (B) Volatile matter in coke is zero (C) Temperature maintained is 700°C (D) Yield of tar is about 3% of dry coal
Last Answer : (C) Temperature maintained is 700°C
Description : Presence of free moisture in coal during its high temperature carbonisation (A) Reduces the coking time (B) Protects the volatile products from pyrolysis (cracking) in the presence of hot coke and hot oven walls (C) Increases the loss of fine coal dust from the ovens when charging (D) None of these
Last Answer : (B) Protects the volatile products from pyrolysis (cracking) in the presence of hot coke and hot oven walls
Description : Prime coking coal is always blended with medium or non- coking coal before carbonisation (A) To check against its excessive swelling during heating, which may exert high pressure and damage coke oven walls (B) Because, it alone produces unreactive coke (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : Blast furnace coke is made from coal by (A) Low temperature carbonisation (B) High temperature carbonisation (C) Medium temperature carbonisation (D) Heating the coal in an oven in presence of air
Last Answer : (B) High temperature carbonisation
Description : Soft coke is not (A) Produced by low temperature carbonisation of coal (B) A domestic fuel (C) Used in blast furnaces (D) None of these
Last Answer : (C) Used in blast furnaces
Description : The main product of high temperature carbonisation of coal is (A) Coke (B) Ammonia (C) Tar (D) Coke oven gas
Last Answer : (A) Coke
Description : Quantity of coke oven gas produced by high temperature carbonisation of one ton of dry coal may be around __________ Nm3 . (A) 30 (B) 300 (C) 3,000 (D) 30,000
Last Answer : (B) 300
Description : A coal having higher volatile matter content, has lower (A) Smoking tendency on burning (B) Coke oven gas yield on carbonisation (C) Chance of catching fire during storage in open space (D) Ignition temperature
Last Answer : (D) Ignition temperature
Description : High ash coals (A) Are soft & friable (poor strength and size stability) (B) Require longer time of carbonisation as ash offers resistance to heat transfer (C) Produce larger quantity of coke oven gas (D) None of these
Last Answer : (A) Are soft & friable (poor strength and size stability)
Description : Beehive coke oven (A) Facilitates by-products recovery (B) Takes 2-3 days for coking of coal but requires no external fuel for heating (C) Gives larger yield of coke (around 85%) as compared to by-product ovens (D) Produces coke with very poor strength
Last Answer : (B) Takes 2-3 days for coking of coal but requires no external fuel for heating
Description : Pick out the wrong statement. (A) Percentage of ash in coke produced from medium coking coal is more than that in coal (B) The calorific value (kcal/Nm3 ) of coke oven gas reduces on ... plants in India at Talcher (Orissa) and Ramagundam (A.P) employ Kopper-Totzek process of coal gasification
Last Answer : (C) Ash is normally removed as 'fly-ash' in Kopper-Totzek process of coal gasification
Description : . A coal having high volatile matter content will (A) Give less yield of tar and gas on carbonisation (B) Burn with a small non-smoky flame (C) Have a very high calorific value (D) None of these
Description : Coke oven gas is a better fuel than blast furnace gas, because of its higher (A) Calorific value, cleanliness and relatively low distribution cost (due to its low specific gravity) (B) Adiabatic flame temperature ... release rate (thus requiring smaller combustion chamber) (D) All (A), (B) and (C)
Description : In high temperature carbonisation (as compared to low temperature carbonisation) of coal, the (A) Gas yield is less (B) Tar yield is more (C) Ignition temperature of coke produced is less (D) Aromatic content of tar produced is more
Last Answer : (D) Aromatic content of tar produced is more
Description : Blast furnace gas compared to coke oven gas has (A) Lower ignition temperature (B) Narrower limit of inflammability (C) Higher calorific value (D) Lower theoretical flame temperature
Last Answer : (D) Lower theoretical flame temperature
Description : With increase in the time of carbonisation at a particular temperature(say 1000°C), the __________ percentage in coke oven gas increases. (A) Hydrogen (B) Methane (C) Unsaturated hydrocarbons (D) All (A), (B) and (C)
Last Answer : (A) Hydrogen
Description : With increases in carbonisation temperature (A) Coke even gas yield increases (B) Tar yield increases (C) Hydrogen percentage in the coke oven gas decreases (D) Methane percentage in the coke oven gas increases
Last Answer : (A) Coke even gas yield increases
Description : Fussain (A) Is friable, charcoal like substance (B) Has highest fixed carbon and lowest volatile matter content of all the four banded components of coal (C) Is non-coking, but when blended with highly coking ... its swelling and produces high strength coke on carbonisation (D) All (A), (B) and (C)
Description : High rate of heating of coke ovens (A) May damage its walls due to abrupt excessive swelling of coal (B) Produces larger size coke (C) Increases the time of carbonisation (D) None of these
Last Answer : (A) May damage its walls due to abrupt excessive swelling of coal
Description : Presence of phosphorous in metallurgical coal (A) Is not undesirable (B) Reduces its calorific value (C) Badly affects the quality of steel
Last Answer : (C) Badly affects the quality of steel
Description : Which of the following has the least calorific value (kcal/Nm3 )? (A) Blast furnace gas (B) Coke oven gas (C) Sewage gas (D) Natural gas
Last Answer : (A) Blast furnace gas
Description : Gross & net calorific value is the same for (A) Blast furnace gas (B) Coke oven gas (C) L.D. converter gas (D) None of these
Last Answer : (C) L.D. converter gas
Description : Removal of hydrogen from coke oven gas (A) Increases its calorific value (B) Decreases its calorific value (C) Does not alter its calorific value (D) Is not possible on commercial scale
Last Answer : (A) Increases its calorific value
Description : Out of the following fuels, the difference between gross and net calorific value will be minimum in case of (A) Coke oven gas (B) Water gas (C) Natural gas (D) Blast furnace gas
Last Answer : (D) Blast furnace gas
Description : Which of the following has the highest gross calorific value? (A) Blast furnace gas (B) Coke oven gas (C) Carburetted water gas (D) Oil refinery gas
Last Answer : (D) Oil refinery gas
Description : For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm3 ), while the C.V. is same on weight basis (i.e., kcal/kg)? (A) Propane and acetylene (B) Propane and LPG (C) Sewage gas and gobar gas (D) B.F. gas and coke oven gas
Last Answer : (A) Propane and acetylene
Description : The calorific value is the highest out of the following for (A) Producer gas (B) Water gas (C) Coke oven gas (D) Blast furnace gas
Last Answer : (C) Coke oven gas
Description : Calorific value of coke oven gas is around __________ Kcal/Nm3 . (A) 900 (B) 4200 (C) 7500 (D) 2000
Last Answer : (B) 4200
Description : For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm3) while the C.V. is same on weight basis (i.e., kcal/kg)? (A ... and acetylene (B) Propane and LPG (C) Sewage gas and gobar gas (D) B.F gas and coke oven gas
Last Answer : D) B.F gas and coke oven gas
Description : With increase in moisture content of coal, its (A) Calorific value increases (B) Caking properties diminish (C) Swelling during carbonisation becomes excessive (D) None of these
Last Answer : (B) Caking properties diminish
Description : A coal having high amount of volatile matter (A) Would require smaller combustion chamber (B) Produces very little of tar and gas on carbonisation (C) Ignites easily and burns with long smoky flame (D) All (A), (B) and (C)
Description : Preheating of coal charge for the coke ovens reduces the (A) Time of carbonisation (B) Yield of gas and tar (C) Fuel consumption in coking (D) All (A), (B) and (C)
Description : Heat penetration rate in narrow coke ovens in high temperature carbonisation of coal is around __________ cm/hr. (A) 2.5 (B) 0.5 (C) 10 (D) 20
Last Answer : (A) 2.5
Description : The main product of high temperature carbonisation of coal is (A) Coke (B) Ammonia (C) Tar (D) Phenol
Description : A good metallurgical coke should have very low (A) Sulphur & phosphorous content (B) Porosity (C) Fusion point of its ash (D) Hardness & strength
Last Answer : (A) Sulphur & phosphorous content
Description : . Highly caking coals (A) Produce weak coke (B) Produce strong coke (C) May damage the coke oven walls during carbonisation (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : Width of the coke oven towards coke side is slightly more than that on pusher side to (A) Facilitate easy discharging of coke as it swells during carbonisation (B) Facilitate uniform heating of the oven (C) Increase the output of the coke (D) None of these
Last Answer : (A) Facilitate easy discharging of coke as it swells during carbonisation
Description : Higher percentage of ash in coal meant for the production of metallurgical grade coke (A) Decreases the hardness of coke (B) Decreases the abrasion resistance of coke (C) Causes brittleness in steel (D) None of these
Description : Quantity of coke produced from metallurgical coal may be around __________ percent. (A) 30 (B) 50 (C) 75 (D) 95
Last Answer : (C) 75