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

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
by

1 Answer

Answer :

(B) Protects the volatile products from pyrolysis (cracking) in the presence
of hot coke and hot oven walls
by

Related questions

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 : 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)

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

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)

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)

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

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

Sometimes water is sprayed during coal charging in the coke oven, which helps in (A) Prevention of clinker formation in the oven (B) Controlling the dust nuisance while charging the coal (C) Reducing the cracking of hydrocarbons in the gas and increasing the percentage of CO & H2 in the gas (due to the endothermic reaction represented by C + H2O = CO + H2 ) (D) All (A), (B) and (C)

Description : Sometimes water is sprayed during coal charging in the coke oven, which helps in (A) Prevention of clinker formation in the oven (B) Controlling the dust nuisance while charging the coal (C) Reducing the cracking of hydrocarbons in ... represented by C + H2O = CO + H2 ) (D) All (A), (B) and (C)

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

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 monoxidecontent increases(C) Calorific value of the coke oven gas decreases due to cracking ofhydrocarbons which is not compensated by increase in CO & H2 content(D) All (A), (B) and (C)

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)

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

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

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

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 coal, controls its swelling and produces high strength coke on carbonisation (D) All (A), (B) and (C)

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)

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

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

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

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

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

Degree of carbonisation of coal during coke making can be roughly judged by the __________ of the coke produced. (A) Colour (B) Moisture content (C) Ash content (D) Volatile matter

Description : Degree of carbonisation of coal during coke making can be roughly judged by the __________ of the coke produced. (A) Colour (B) Moisture content (C) Ash content (D) Volatile matter

Last Answer : (D) Volatile matter

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

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

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 removal of hydrogen from it by cryogenic method (C) Ash is normally removed as 'fly-ash' in Kopper-Totzek process of coal gasification (D) Coal based fertiliser plants in India at Talcher (Orissa) and Ramagundam (A.P) employ Kopper-Totzek process of coal gasification

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

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

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

Low temperature carbonisation of coal produces (A) Metallurgical coke (B) Soft coke (C) Very low calorific value coke oven gas (D) No by-products

Description : Low temperature carbonisation of coal produces (A) Metallurgical coke (B) Soft coke (C) Very low calorific value coke oven gas (D) No by-products

Last Answer : (B) Soft coke

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)

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)

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

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

The main product of high temperature carbonisation of coal is (A) Coke (B) Ammonia (C) Tar (D) Coke oven gas

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

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

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

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)

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)

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

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

. 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)

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)

Which of the following processes in oil refinery does not employ ‘cracking’? (A) Coking (B) Visbreaking (C) Pyrolysis (D) None of these

Description : Which of the following processes in oil refinery does not employ ‘cracking’? (A) Coking (B) Visbreaking (C) Pyrolysis (D) None of these

Last Answer : (D) None of these

Anthracite can be used for (A) Recarbonising steel (B) Making carbon electrodes(C) Blending with highly coking coal to check its swelling which helps insaving coke even walls from damage and to produce high strength coke(D) All (A), (B) and (C)

Description : Anthracite can be used for (A) Recarbonising steel (B) Making carbon electrodes (C) Blending with highly coking coal to check its swelling which helps in saving coke even walls from damage and to produce high strength coke (D) All (A), (B) and (C)

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

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

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

Main use of hard coke produced by high temperature carbonisation is in the (A) Iron blast furnace (B) Cupola in foundries (C) Sinter making (D) Domestic ovens

Description : Main use of hard coke produced by high temperature carbonisation is in the (A) Iron blast furnace (B) Cupola in foundries (C) Sinter making (D) Domestic ovens

Last Answer : (A) Iron blast furnace

Pick out the wrong statement. (A) Indian coals on an average contain 25-30% ash as against 10-12% ash in imported coking coal (B) Ammonia is recovered in the form of ammonium sulphate in direct process of by-product recovery (C) A high swelling index number of coking coal indicates poor caking properties of coal (D) Wash oil is used for scrubbing Benzol from coke oven gas

Description : Pick out the wrong statement. (A) Indian coals on an average contain 25-30% ash as against 10-12% ash in imported coking coal (B) Ammonia is recovered in the form of ammonium sulphate in direct ... indicates poor caking properties of coal (D) Wash oil is used for scrubbing Benzol from coke oven gas

Last Answer : (C) A high swelling index number of coking coal indicates poor caking properties of coal

Coking time in a commercial high temperature coal carbonisation plant is about __________ hours. (A) 6 (B) 18 (C) 28

Description : Coking time in a commercial high temperature coal carbonisation plant is about __________ hours. (A) 6 (B) 18 (C) 28

Last Answer : (B) 18

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)

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

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

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

Which of the following fuels is generally not used in thermal power plant boiler firing? (A) Furnace oil, light diesel oil and tar/PCM (B) Pulverised coking coal (C) Coal middling from washeries (D) B.F. gas, coke oven gas and L.D. converter gas

Description : Which of the following fuels is generally not used in thermal power plant boiler firing? (A) Furnace oil, light diesel oil and tar/PCM (B) Pulverised coking coal (C) Coal middling from washeries (D) B.F. gas, coke oven gas and L.D. converter gas

Last Answer : (B) Pulverised coking coal

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

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

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 : 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

Last Answer : (D) None of these

Undercharging of coal in the by-product coke ovens results in (A) Decrease in the c.v. of coke oven gas (B) Increase in its throughput (C) Increase in the c.v. of coke oven gas

Description : Undercharging of coal in the by-product coke ovens results in (A) Decrease in the c.v. of coke oven gas (B) Increase in its throughput (C) Increase in the c.v. of coke oven gas

Last Answer : (A) Decrease in the c.v. of coke oven gas

Coking time in narrow by-product coke ovens is around __________ hours. (A) 18 (B) 48 (C) 8 (D) 80

Description : Coking time in narrow by-product coke ovens is around __________ hours. (A) 18 (B) 48 (C) 8 (D) 80

Last Answer : (A) 18

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

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

Phenolic water generated in coke ovens & by-product plant of a steel plant are disposed off by (A) Quenching of hot coke (B) Discharging in the river stream (C) Filtration and recycling for cooling coke oven gas (D) None of these

Description : Phenolic water generated in coke ovens & by-product plant of a steel plant are disposed off by (A) Quenching of hot coke (B) Discharging in the river stream (C) Filtration and recycling for cooling coke oven gas (D) None of these

Last Answer : (A) Quenching of hot coke

Narrow coke ovens as compared to wider coke ovens (A) Produce smaller coke (B) Produce stronger coke (C) Require less time of carbonisation (D) All (A), (B) and (C)

Description : Narrow coke ovens as compared to wider coke ovens (A) Produce smaller coke (B) Produce stronger coke (C) Require less time of carbonisation (D) All (A), (B) and (C)

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

Washing of coal (A) Reduces its sulphur and ash content (B) Controls its ash fusibility and increases its calorific value(C) Improves its coking properties(D) All (A), (B) and (C)

Description : Washing of coal (A) Reduces its sulphur and ash content (B) Controls its ash fusibility and increases its calorific value (C) Improves its coking properties (D) All (A), (B) and (C)

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

Petroleum coke is commercially produced by the __________ process. (A) Hydrocracking (B) Visbreaking (C) Fluid catalytic cracking (D) Delayed coking

Description : Petroleum coke is commercially produced by the __________ process. (A) Hydrocracking (B) Visbreaking (C) Fluid catalytic cracking (D) Delayed coking

Last Answer : (D) Delayed coking

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

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

The main product of high temperature carbonisation of coal is (A) Coke (B) Ammonia (C) Tar (D) Phenol

Description : The main product of high temperature carbonisation of coal is (A) Coke (B) Ammonia (C) Tar (D) Phenol

Last Answer : (A) Coke

Cannel coal (A) Is non-coking (B) Has a high volatile matter content and burns with a luminous smoky flame (C) Is a non-banded coal which can be ignited easily with a match stick or candle flame, hence is so named (D) All (A), (B) and (C

Description : Cannel coal (A) Is non-coking (B) Has a high volatile matter content and burns with a luminous smoky flame (C) Is a non-banded coal which can be ignited easily with a match stick or candle flame, hence is so named (D) All (A), (B) and (C

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

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

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)

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

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

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 : 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)

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

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 : 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)

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

Coking time in beehive coke oven is about (A) 12 hours (B) 2-3 days (C) One week (D) Two weeks

Description : Coking time in beehive coke oven is about (A) 12 hours (B) 2-3 days (C) One week (D) Two weeks

Last Answer : (B) 2-3 days

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

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

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

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