During coal carbonisation process, the conversion of semi-coke to coke is accompanied by an increase in the __________ of the mass. (A) Density (B) Porosity (C) Electrical resistivity (D) None of these

During coal carbonisation process, the conversion of semi-coke to coke
is accompanied by an increase in the __________ of the mass.
(A) Density
(B) Porosity
(C) Electrical resistivity
(D) None of these
by

1 Answer

Answer :

(A) Density
by

Related questions

During the carbonisation of coal (A) All tar is evolved at < 600°C (B) Evolution of H2 and formation of methane and aromatics occur at > 700°C (C) Hard semi-coke starts shrinking at 600°C (D) All (A), (B) and (C)

Description : During the carbonisation of coal (A) All tar is evolved at < 600°C (B) Evolution of H2 and formation of methane and aromatics occur at > 700°C (C) Hard semi-coke starts shrinking at 600°C (D) All (A), (B) and (C)

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

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)

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

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

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

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

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

. By-products recovery process from coal carbonisation is termed asdirect, indirect and semi direct process depending upon the method of recovery of (A) Tar (B) Benzol (C) Ammonia (D) None of these

Description : . By-products recovery process from coal carbonisation is termed asdirect, indirect and semi direct process depending upon the method of recovery of (A) Tar (B) Benzol (C) Ammonia (D) None of these

Last Answer : (C) Ammonia

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)

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

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

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

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

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)

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

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

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

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)

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)

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

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

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

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

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

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)

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

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

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

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

Producer gas is obtained by  A. partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast  B. carbonisation of bituminous coal  C. passing steam over incandescent coke  D. passing air and a large amount of steam over waste coal at about 650°C

Description : Producer gas is obtained by  A. partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast  B. carbonisation of bituminous coal  C. passing steam over incandescent coke  D. passing air and a large amount of steam over waste coal at about 650°C

Last Answer : Answer: A

Producer gas is obtained by  A. partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast  B. carbonisation of bituminous coal  C. passing steam over incandescent coke  D. passing air and a large amount of steam over waste coal at about 650°C

Description : Producer gas is obtained by  A. partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast  B. carbonisation of bituminous coal  C. passing steam over incandescent coke  D. passing air and a large amount of steam over waste coal at about 650°C

Last Answer : Answer: A

Coke used for the production of calcium carbide should have (A) Low ash content (B) Low ignition temperature (C) High electrical resistivity (D) All (A), (B) and (C)

Description : Coke used for the production of calcium carbide should have (A) Low ash content (B) Low ignition temperature (C) High electrical resistivity (D) All (A), (B) and (C)

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

Coke having higher porosity has (A) Lower bulk density (B) Lower strength (C) Higher reactivity (D) All (A), (B) and (C)

Description : Coke having higher porosity has (A) Lower bulk density (B) Lower strength (C) Higher reactivity (D) All (A), (B) and (C)

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

"Micum Index" of a coke is a measure of its (A) Reactivity (B) Porosity (C) Bulk density (D) Hardness & strength

Description : "Micum Index" of a coke is a measure of its (A) Reactivity (B) Porosity (C) Bulk density (D) Hardness & strength

Last Answer : (D) Hardness & strength

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

The temperature at which plastic layer formation takes place during carbonisation of coal varies from __________ °C. (A) 100 to 150 (B) 350 to 450 (C) 550 to 650 (D) 700 to 850

Description : The temperature at which plastic layer formation takes place during carbonisation of coal varies from __________ °C. (A) 100 to 150 (B) 350 to 450 (C) 550 to 650 (D) 700 to 850

Last Answer : (B) 350 to 450

Hard coke is manufactured from (A) Lignite (B) Bituminous coal (C) Semi-anthracite (D) Anthracite

Description : Hard coke is manufactured from (A) Lignite (B) Bituminous coal (C) Semi-anthracite (D) Anthracite

Last Answer : (B) Bituminous coal

Which will have the least volatile matter and hence will be the most difficult to ignite? (A) Bituminous coal (B) Coke (C) Semi-bituminous coal (D) Anthracite

Description : Which will have the least volatile matter and hence will be the most difficult to ignite? (A) Bituminous coal (B) Coke (C) Semi-bituminous coal (D) Anthracite

Last Answer : (B) Coke

Which of the following would require least amount of secondary air for combustion? (A) Coke breeze containing 25% ash and 2% volatile matter (B) Anthracite containing 10% volatile matter and 8% ash(C) Bituminous coal containing 20% ash and 25% volatile matter(D) Semi-bituminous coal containing 25% ash and 20% volatile matter

Description : Which of the following would require least amount of secondary air for combustion? (A) Coke breeze containing 25% ash and 2% volatile matter (B) Anthracite containing 10% volatile matter and 8% ash ... ash and 25% volatile matter (D) Semi-bituminous coal containing 25% ash and 20% volatile matter

Last Answer : (A) Coke breeze containing 25% ash and 2% volatile matter

. 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)

When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel, the process is known as __________ of fuel.  A. atomisation  B. carbonisation

Description : When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel, the process is known as __________ of fuel.  A. atomisation  B. carbonisation

Last Answer : Answer: B

Commercial production of petrol from coal (as practised in a factory at Sasol in South Africa) is done by the __________ of coal. (A) Hydrogenation (B) Gasification (C) Carbonisation (D) None of these

Description : Commercial production of petrol from coal (as practised in a factory at Sasol in South Africa) is done by the __________ of coal. (A) Hydrogenation (B) Gasification (C) Carbonisation (D) None of these

Last Answer : (A) Hydrogenation

When steam is passed over coal resulting in the endothermic reaction represent by, C + H2O = CO + H2 , it is called the __________ of coal. (A) Carbonisation (B) Oxidation (C) Coalification (D) Gasification

Description : When steam is passed over coal resulting in the endothermic reaction represent by, C + H2O = CO + H2 , it is called the __________ of coal. (A) Carbonisation (B) Oxidation (C) Coalification (D) Gasification

Last Answer : (D) Gasification

Low temperature carbonisation of coal takes place at __________ °C. (A) 300 (B) 1100 (C) 700

Description : Low temperature carbonisation of coal takes place at __________ °C. (A) 300 (B) 1100 (C) 700

Last Answer : (C) 700

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

High temperature carbonisation of coal takes place at __________ °C. (A) 2000 (B) 600 (C) 1100 (D) 1600

Description : High temperature carbonisation of coal takes place at __________ °C. (A) 2000 (B) 600 (C) 1100 (D) 1600

Last Answer : (C) 1100

Tar yield in the low temperature and high temperature carbonisation of dry coal may be respectively __________ percent. (A) 3 & 10 (B) 10 & 3 (C) 10 & 20 (D) 15 & 8

Description : Tar yield in the low temperature and high temperature carbonisation of dry coal may be respectively __________ percent. (A) 3 & 10 (B) 10 & 3 (C) 10 & 20 (D) 15 & 8

Last Answer : (B) 10 & 3

High temperature carbonisation of coal takes place at __________ °C. (A) 2000 (B) 700 (C) 1100 (D) < 500

Description : High temperature carbonisation of coal takes place at __________ °C. (A) 2000 (B) 700 (C) 1100 (D) < 500

Last Answer : (C) 1100

The yield of tar from high temperature carbonisation of dry coal is about __________ percent. (A) 3 (B) 12 (C) 22 (D) 0.3

Description : The yield of tar from high temperature carbonisation of dry coal is about __________ percent. (A) 3 (B) 12 (C) 22 (D) 0.3

Last Answer : (A) 3

Low temperature carbonisation of coal takes place at __________ °C. (A) 300 (B) 1100 (C) 700 (D) 900

Description : Low temperature carbonisation of coal takes place at __________ °C. (A) 300 (B) 1100 (C) 700 (D) 900

Last Answer : (C) 700