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

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
by

1 Answer

Answer :

(A) Coke breeze containing 25% ash and 2% volatile matter
by

Related questions

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

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

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

Anthracite coal (A) Contains more volatile matter than bituminous coal (B) Ignites more easily than bituminous coal (C) Is essentially a coking coal (D) Burns with short, bluish, yellow-tipped flame producing very little smoke

Description : Anthracite coal (A) Contains more volatile matter than bituminous coal (B) Ignites more easily than bituminous coal (C) Is essentially a coking coal (D) Burns with short, bluish, yellow-tipped flame producing very little smoke

Last Answer : (D) Burns with short, bluish, yellow-tipped flame producing very little smoke

Which of the following type of coal has the lowest proportion of volatile matter? (1) Lignite (2) Peat (3) Bituminous (4) Anthracite

Description : Which of the following type of coal has the lowest proportion of volatile matter? (1) Lignite (2) Peat (3) Bituminous (4) Anthracite

Last Answer : (4) Anthracite Explanation: Anthracite has the lowest proportion of volatile matter. Volatile matter in coal refers to the components of coal, except for moisture, which are liberated at ... hydrocarbons and some sulfur. The volatile matter of coal is determined under rigidly controlled standards.

Which of the following type of coal has the lowest proportion of volatile matter ? (1) Lignite (2) Peat (3) Bituminous (4) Anthracite

Description : Which of the following type of coal has the lowest proportion of volatile matter ? (1) Lignite (2) Peat (3) Bituminous (4) Anthracite

Last Answer : Anthracite

Pick out the wrong statement. (A) High concentration of oxygen in flue gas means high stack loss (B) Gaseous fuels require the least % excess air for complete combustion (C) The ratio of fixed carbon to volatile matter percentage in coal is called its 'fuel ratio' (D) Calorific value of natural gas is more than that of LPG

Description : Pick out the wrong statement. (A) High concentration of oxygen in flue gas means high stack loss (B) Gaseous fuels require the least % excess air for complete combustion (C) The ratio of fixed carbon to ... coal is called its 'fuel ratio' (D) Calorific value of natural gas is more than that of LPG

Last Answer : (D) Calorific value of natural gas is more than that of LPG

A coal containing high amount of volatile matter will have (A) Low ignition temperature (B) Very little ash content (C) High fusion point of its ash (D) Low adiabatic flame temperature

Description : A coal containing high amount of volatile matter will have (A) Low ignition temperature (B) Very little ash content (C) High fusion point of its ash (D) Low adiabatic flame temperature

Last Answer : (A) Low ignition temperature

Which of the following must be stored in silos and not in open yard? (A) Coke breeze (B) High V.M. bituminous coal (C) Sand (D) None of these

Description : Which of the following must be stored in silos and not in open yard? (A) Coke breeze (B) High V.M. bituminous coal (C) Sand (D) None of these

Last Answer : (B) High V.M. bituminous coal

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)

Which of the following is the most reactive (as regards the formation of CO + H2 from C + H2O)? (A) Blast furnace coke (B) Low temperature coke (C) Anthracite coal (D) Sub-bituminous coa

Description : Which of the following is the most reactive (as regards the formation of CO + H2 from C + H2O)? (A) Blast furnace coke (B) Low temperature coke (C) Anthracite coal (D) Sub-bituminous coa

Last Answer : (B) Low temperature coke

The difference between total carbon and fixed carbon of coal will be minimum in case of (A) Lignite (B) Bituminous coal (C) Anthracite (D) High temperature coke (V.M < 0.5%)

Description : The difference between total carbon and fixed carbon of coal will be minimum in case of (A) Lignite (B) Bituminous coal (C) Anthracite (D) High temperature coke (V.M < 0.5%)

Last Answer : (D) High temperature coke (V.M < 0.5%)

The most matured coal out of the following is(A) Lignite (B) Semi-anthracite (C) Sub-bituminous (D) Bituminous

Description : The most matured coal out of the following is (A) Lignite (B) Semi-anthracite (C) Sub-bituminous (D) Bituminous

Last Answer : (B) Semi-anthracite

Which is the most matured coal? (A) Lignite (B) Bituminous (C) Semi-anthracite (D) Anthracite

Description : Which is the most matured coal? (A) Lignite (B) Bituminous (C) Semi-anthracite (D) Anthracite

Last Answer : (D) Anthracite

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

Coke compared to the coal from which it has been made, contains (A) Less volatile matter (B) More carbon (C) Greater percentage of ash (D) All (A), (B) and (C)

Description : Coke compared to the coal from which it has been made, contains (A) Less volatile matter (B) More carbon (C) Greater percentage of ash (D) All (A), (B) and (C)

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

Fixed carbon in coal is defined as (A) That present in volatile matters (B) The total quantity of carbon present in the coal (C) Hundred minus the percentage of volatile matter, ash and moisture (D) The one which is present in the residue after combustion

Description : Fixed carbon in coal is defined as (A) That present in volatile matters (B) The total quantity of carbon present in the coal (C) Hundred minus the percentage of volatile matter, ash and moisture (D) The one which is present in the residue after combustion

Last Answer : (C) Hundred minus the percentage of volatile matter, ash and moisture

Producer gas containing least amount of tar is produced by the (A) Partial combustion of coal (B) Partial combustion of large size (< 50 mm) coke (C) High pressure gasification of coal (e.g. in Lurgi gasifier) (D) Atmospheric pressure gasification of coal (e.g., in Kopper-Totzek gasifier)

Description : Producer gas containing least amount of tar is produced by the (A) Partial combustion of coal (B) Partial combustion of large size (< 50 mm) coke (C) High pressure gasification of coal (e.g. in Lurgi gasifier) (D) Atmospheric pressure gasification of coal (e.g., in Kopper-Totzek gasifier)

Last Answer : (B) Partial combustion of large size (< 50 mm) coke

Which one of the following is known as the 'brown coal'? (1) Anthracite (2) Bituminous (3) Coke (4) Lignite

Description : Which one of the following is known as the 'brown coal'? (1) Anthracite (2) Bituminous (3) Coke (4) Lignite

Last Answer : (4) Lignite Explanation: Lignite, often referred to as brown coal, is a soft brown fuel with characteristics that put it somewhere between coal and peat. It is considered the lowest rank of coal. It has ... 66%, and an ash content ranging from 6% to 19% compared with 6% to 12% for bituminous coal.

Which one of the following is known as the ‘brown coal’? (1) Anthracite (2) Bituminous (3) Coke (4) Lignite

Description : Which one of the following is known as the ‘brown coal’? (1) Anthracite (2) Bituminous (3) Coke (4) Lignite

Last Answer : (4) Lignite Explanation: Lignite, often referred to as brown coal, is a soft brown fuel with characteristics that put it somewhere between coal and peat. It is considered the lowest rank of coal. It has a carbon content of around 2530%.

Which one of the following is known as the ‘brown coal’ ? (1) Anthracite (2) Bituminous (3) Coke (4) Lignite

Description : Which one of the following is known as the ‘brown coal’ ? (1) Anthracite (2) Bituminous (3) Coke (4) Lignite

Last Answer : Lignite

The function of secondary combustion air is to (A) Pneumatically convey the pulverised coal (B) Completely burn the volatile matter (C) Burn the lumpy coal (D) None of these

Description : The function of secondary combustion air is to (A) Pneumatically convey the pulverised coal (B) Completely burn the volatile matter (C) Burn the lumpy coal (D) None of these

Last Answer : (B) Completely burn the volatile matter

A coal having high ratio of volatile matter to fixed carbon as compared to a coal having low ratio of volatile matter to fixed carbon (A) Is less liable to spontaneous combustion on storage (B) Is more difficult to ignite and produces a shorter flame (C) Requires smaller combustion space and less secondary air (D) None of these

Description : A coal having high ratio of volatile matter to fixed carbon as compared to a coal having low ratio of volatile matter to fixed carbon (A) Is less liable to spontaneous combustion on storage (B) ... a shorter flame (C) Requires smaller combustion space and less secondary air (D) None of these

Last Answer : (D) None of these

Coal containing large quantity of __________ are difficult to wash. (A) Ash (B) Inherent mineral matter (C) Free impurities (D) Volatile matter

Description : Coal containing large quantity of __________ are difficult to wash. (A) Ash (B) Inherent mineral matter (C) Free impurities (D) Volatile matter

Last Answer : (B) Inherent mineral matter

Ignition temperature decreases progressively from anthracite to lignite, because (A) Volatile matter content increases (B) Carbon content decreases (C) Moisture content increases (D) Ash content increases

Description : Ignition temperature decreases progressively from anthracite to lignite, because (A) Volatile matter content increases (B) Carbon content decreases (C) Moisture content increases (D) Ash content increases

Last Answer : (A) Volatile matter content increases

Which of the following is unsuitable fuel for producer gas manufacture? (A) Coke (B) Anthracite (C) Coal having low fusion point of its ash (D) Coal having high fusion point of its ash

Description : Which of the following is unsuitable fuel for producer gas manufacture? (A) Coke (B) Anthracite (C) Coal having low fusion point of its ash (D) Coal having high fusion point of its ash

Last Answer : (C) Coal having low fusion point of its ash

Which of the following would require maximum amount of % excess air for complete combustion? (A) Coke oven gas (B) Furnace oil (C) Pulverised coal (D) Lump coal (fixed on chain grate)

Description : Which of the following would require maximum amount of % excess air for complete combustion? (A) Coke oven gas (B) Furnace oil (C) Pulverised coal (D) Lump coal (fixed on chain grate)

Last Answer : (D) Lump coal (fixed on chain grate)

Ratio of primary air to secondary air increases with increase in the rank of coal, because the (A) High rank coals have higher amount of volatile matter (B) Ratio of fixed carbon to volatile matter increases (C) Oxygen content progressively decreases (D) Calorific value of the coal increases

Description : Ratio of primary air to secondary air increases with increase in the rank of coal, because the (A) High rank coals have higher amount of volatile matter (B) Ratio of fixed carbon to volatile matter increases (C) Oxygen content progressively decreases (D) Calorific value of the coal increases

Last Answer : (B) Ratio of fixed carbon to volatile matter increases

Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if (A) It contains large amount of volatile matter (B) It is stored in tall heaps (C) Smaller fines are stored in large quantity (D) All (A), (B) and (C)

Description : Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if (A) It contains large amount of volatile matter (B) It is stored in tall heaps (C) Smaller fines are stored in large quantity (D) All (A), (B) and (C)

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

Out of the following, which is the most important parameter for the blast furnace grade coke? (A) CSR & CRI (B) Ash content (C) Moisture content (D) Volatile matter content

Description : Out of the following, which is the most important parameter for the blast furnace grade coke? (A) CSR & CRI (B) Ash content (C) Moisture content (D) Volatile matter content

Last Answer : (A) CSR & CRI

Coals used for the generation of producer gas should have (A) High caking index (B) Low fusion point of ash (C) High volatile matter content (D) Very low ash content (8-10%)

Description : Coals used for the generation of producer gas should have (A) High caking index (B) Low fusion point of ash (C) High volatile matter content (D) Very low ash content (8-10%)

Last Answer : (C) High volatile matter content

Ash content in the coke produced from a coking coal having 20% ash may be around __________ percent. (A) 6 (B) 12 (C) 18 (D) 24

Description : Ash content in the coke produced from a coking coal having 20% ash may be around __________ percent. (A) 6 (B) 12 (C) 18 (D) 24

Last Answer : (D) 24

Which of the following can be made into briquettes without the use of a binder? (A) Lignite (B) Bituminous coal (C) Anthracite coal (D) None of these

Description : Which of the following can be made into briquettes without the use of a binder? (A) Lignite (B) Bituminous coal (C) Anthracite coal (D) None of these

Last Answer : (A) Lignite

Which of the following has the highest calorific value? (A) Lignite (B) Sub-bituminous coal (C) Anthracite (D) Peat

Description : Which of the following has the highest calorific value? (A) Lignite (B) Sub-bituminous coal (C) Anthracite (D) Peat

Last Answer : (C) Anthracite

Bituminous coal (A) Ignites less easily than anthracite (B) Is generally coking (C) Burns with smoky yellow flame (D) Both (B) and (C)

Description : Bituminous coal (A) Ignites less easily than anthracite (B) Is generally coking (C) Burns with smoky yellow flame (D) Both (B) and (C)

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

The reason for excessive clinker formation in gas producers is the (A) Use of coal/coke containing a high % of fines and ash (B) Use of fuel having too low an ash fusion temperature (C) Development of hot spots in the fuel bed and an abnormally high rate of gasification (D) All (A), (B) and (C)

Description : The reason for excessive clinker formation in gas producers is the (A) Use of coal/coke containing a high % of fines and ash (B) Use of fuel having too low an ash fusion temperature (C) Development of hot spots in the fuel bed and an abnormally high rate of gasification (D) All (A), (B) and (C)

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

The specific gravity of coal depends mainly on its __________ content. (A) Carbon (B) Volatile matter (C) Ash (D) Moisture

Description : The specific gravity of coal depends mainly on its __________ content. (A) Carbon (B) Volatile matter (C) Ash (D) Moisture

Last Answer : (C) Ash

Ultimate analysis of coal determines its __________ content. (A) Carbon, hydrogen, nitrogen & sulphur (B) Carbon, ash, sulphur & nitrogen (C) Carbon, sulphur, volatile matter & ash (D) Carbon, volatile matter, ash & moisture

Description : Ultimate analysis of coal determines its __________ content. (A) Carbon, hydrogen, nitrogen & sulphur (B) Carbon, ash, sulphur & nitrogen (C) Carbon, sulphur, volatile matter & ash (D) Carbon, volatile matter, ash & moisture

Last Answer : (A) Carbon, hydrogen, nitrogen & sulphur

For long flame and easy ignition, the coal used should have (A) High volatile matter (B) Low ash (C) High calorific value (D) High ash

Description : For long flame and easy ignition, the coal used should have (A) High volatile matter (B) Low ash (C) High calorific value (D) High ash

Last Answer : (A) High volatile matter

Proximate analysis of coal determines its __________ content. (A) Moisture, ash, sulphur & volatile matter (B) Moisture, volatile matter, ash & fixed carbon (C) Moisture, sulphur, nitrogen & fixed carbon (D) None of these

Description : Proximate analysis of coal determines its __________ content. (A) Moisture, ash, sulphur & volatile matter (B) Moisture, volatile matter, ash & fixed carbon (C) Moisture, sulphur, nitrogen & fixed carbon (D) None of these

Last Answer : (B) Moisture, volatile matter, ash & fixed carbon

Fat' coal means a coal having (A) Low calorific value (B) High volatile matter (C) Low ash content

Description : Fat' coal means a coal having (A) Low calorific value (B) High volatile matter (C) Low ash content

Last Answer : (B) High volatile matter

A coal having higher volatile matter content will necessarily have lower (A) Ash fusion temperature (B) Calorific value (C) Ignition temperature (D) Caking index

Description : A coal having higher volatile matter content will necessarily have lower (A) Ash fusion temperature (B) Calorific value (C) Ignition temperature (D) Caking index

Last Answer : (C) Ignition temperature

A coal with high __________ content, would ignite most easily. (A) Fixed carbon (B) Volatile matter (C) Ash (D) Oxygen

Description : A coal with high __________ content, would ignite most easily. (A) Fixed carbon (B) Volatile matter (C) Ash (D) Oxygen

Last Answer : (B) Volatile matter

Proximate analysis of coal determines its __________ content. (A) Moisture, ash, sulphur & volatile matter (B) Moisture & volatile matter (C) Moisture, sulphur, nitrogen & fixed carbon (D) None of these

Description : Proximate analysis of coal determines its __________ content. (A) Moisture, ash, sulphur & volatile matter (B) Moisture & volatile matter (C) Moisture, sulphur, nitrogen & fixed carbon (D) None of these

Last Answer : (B) Moisture & volatile matter

Ultimate analysis of coal determines its __________ content. (A) Carbon, hydrogen, nitrogen & sulphur (B) Carbon, ash, sulphur & nitrogen(C) Carbon, sulphur, volatile matter & ash(D) Carbon, volatile matter, ash & moisture

Description : Ultimate analysis of coal determines its __________ content. (A) Carbon, hydrogen, nitrogen & sulphur (B) Carbon, ash, sulphur & nitrogen (C) Carbon, sulphur, volatile matter & ash (D) Carbon, volatile matter, ash & moisture

Last Answer : (C) Carbon, sulphur, volatile matter & ash

The specific gravity of coal depends mainly on its __________ content. (A) Carbon (B) Volatile matter (C) Ash (D) Moisture

Description : The specific gravity of coal depends mainly on its __________ content. (A) Carbon (B) Volatile matter (C) Ash (D) Moisture

Last Answer : Option D

Amount of coal lost in ash particle, which is carried through the boiler system, depends upon the (A) Physical nature, ash content and fineness of the coal (B) Amount of excess air supplied and load on the boiler (C) Type of burner and combustion chamber (D) All (A), (B) and (C)

Description : Amount of coal lost in ash particle, which is carried through the boiler system, depends upon the (A) Physical nature, ash content and fineness of the coal (B) Amount of excess air supplied and load on the boiler (C) Type of burner and combustion chamber (D) All (A), (B) and (C)

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

Which one of the following lists four type of coal, arranged in the increasing order of their carbon content? (a) Peat, Lignite, Bituminous, Anthracite (b) Peat, Bituminous, Lignite, Anthracite (c) Lignite, Peat, Bituminous, Anthracite (d) Peat, Anthracite, Lignite, Bituminous

Description : Which one of the following lists four type of coal, arranged in the increasing order of their carbon content? (a) Peat, Lignite, Bituminous, Anthracite (b) Peat, Bituminous, Lignite, Anthracite (c) Lignite, Peat, Bituminous, Anthracite (d) Peat, Anthracite, Lignite, Bituminous

Last Answer : Ans: (a)