Low temperature oxidation of coal resulting from bad storage conditions does not decrease its (A) Caking power (B) Calorific value (C) Hydrogen content (D) Oxygen content

Low temperature oxidation of coal resulting from bad storage
conditions does not decrease its
(A) Caking power
(B) Calorific value
(C) Hydrogen content
(D) Oxygen content
by

1 Answer

Answer :

(D) Oxygen content
by

Related questions

Low temperature oxidation of coal during storage does not decrease its (A) Oxygen content (B) Caking power (C) Calorific value (D) None of these

Description : Low temperature oxidation of coal during storage does not decrease its (A) Oxygen content (B) Caking power (C) Calorific value (D) None of these

Last Answer : (D) None of these

Low temperature oxidation of stored coal results in the (A) Decrease in its caking power & calorific value (B) Decrease in its carbon & hydrogen content (C) Increase in its oxygen content (D) All (A), (B) and (A)

Description : Low temperature oxidation of stored coal results in the (A) Decrease in its caking power & calorific value (B) Decrease in its carbon & hydrogen content (C) Increase in its oxygen content (D) All (A), (B) and (A)

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

Improper storage condition results in the weathering of coal and spontaneous combustion, which increases its (A) Caking index (B) Yield of carbonised products (C) Friability & oxygen content (D) Calorific value

Description : Improper storage condition results in the weathering of coal and spontaneous combustion, which increases its (A) Caking index (B) Yield of carbonised products (C) Friability & oxygen content (D) Calorific value

Last Answer : (C) Friability & oxygen content

With increase in the oxygen content of the coal, its __________ decreases. (A) Calorific value (B) Caking power (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : With increase in the oxygen content of the coal, its __________ decreases. (A) Calorific value (B) Caking power (C) Both (A) & (B) (D) Neither (A) nor (B)

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Pick out the correct statement. (A) Oxygen content decreases from lignite to bituminous coal as the coalification increases (B) The less the oxygen content, better is the coal, as it reduces the calorific value (C) With increase in oxygen content, moisture holding capacity of coal increases and the caking power decreases (D) All (A), (B) and (C)

Description : Pick out the correct statement. (A) Oxygen content decreases from lignite to bituminous coal as the coalification increases (B) The less the oxygen content, better is the coal, as it reduces the calorific value (C ... capacity of coal increases and the caking power decreases (D) All (A), (B) and (C)

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

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

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 weathering index of a coal (A) Gives an idea of the fusion temperature of ash (B) Is related to its calorific value (C) Is a measure of its size stability, when stored & exposed to weather (D) Is a measure of its caking tendency

Description : The weathering index of a coal (A) Gives an idea of the fusion temperature of ash (B) Is related to its calorific value (C) Is a measure of its size stability, when stored & exposed to weather (D) Is a measure of its caking tendency

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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)

__________ of the coal is the basis for Seylor's coal classification. (A) Proximate analysis (B) Ultimate analysis (C) Caking index (D) Calorific value

Description : __________ of the coal is the basis for Seylor's coal classification. (A) Proximate analysis (B) Ultimate analysis (C) Caking index (D) Calorific value

Last Answer : (B) Ultimate analysis

Rate of low temperature oxidation of coal due to bad storage conditions (A) Decreases with increase in surface area (B) Does not vary with increase in surface area (C) Is more for low volatile coal compared to high volatile coal (D) Is accelerated by storage in large heaps with small surface to volume ratio

Description : Rate of low temperature oxidation of coal due to bad storage conditions (A) Decreases with increase in surface area (B) Does not vary with increase in surface area (C) Is more for low volatile ... to high volatile coal (D) Is accelerated by storage in large heaps with small surface to volume ratio

Last Answer : (D) Is accelerated by storage in large heaps with small surface to volume ratio

Weathering of coal during storage causes (A) Reduction in coal size (B) Increase in its friability (C) Decrease in its caking capacity (D) All (A), (B) and (C)

Description : Weathering of coal during storage causes (A) Reduction in coal size (B) Increase in its friability (C) Decrease in its caking capacity (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)

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

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

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

Tar is a better fuel than furnace oil, because of its (A) Higher calorific value (B) Lower sulphur content (C) Higher emissivity (0.8-0.9) resulting in higher radiation heat transfer rate (D) Both (A) and (B)

Description : Tar is a better fuel than furnace oil, because of its (A) Higher calorific value (B) Lower sulphur content (C) Higher emissivity (0.8-0.9) resulting in higher radiation heat transfer rate (D) Both (A) and (B)

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

Explain higher and lower calorific value of a coal having following composition by mass Carbon 81%,Hydrogen 7%, Oxygen 8%,Nitrogen 2.5%, sulphur 1.5% and remaining is ash

Description : Explain higher and lower calorific value of a coal having following composition by mass Carbon 81%,Hydrogen 7%, Oxygen 8%,Nitrogen 2.5%, sulphur 1.5% and remaining is ash

Last Answer : Carbon C = 81% = 0.81 Hydrogen = H2 = 7% = 0.07 Oxygen = O2 = 8% = 0.08 Nitrogen = N = 2.5% = 0.025 Sulphur = S =1.5% = 0.015 Ash = 2.5% = 0.025 Dulong's formula: H.C.V. of coal = 33800 C + 144500 ... = H.C.V.- 9H2 x 2442 KJ / Kg = 36187.5- 9 x 0.07 x 2442 L.C.V. of coal = 34649.04 KJ / Kg 

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 with high ash content (A) Has higher calorific value (B) Is harder and stronger(C) Is not subjected to washing(D) Has low quantity of mineral matter

Description : A coal with high ash content (A) Has higher calorific value (B) Is harder and stronger (C) Is not subjected to washing (D) Has low quantity of mineral matter

Last Answer : (B) Is harder and stronger

Gross and net calorific value of a fuel will be the same (A) If its ash content is zero (B) If its carbon content is very low (C) If its hydrogen/hydrogen compound content is zero (D) Under no circumstances

Description : Gross and net calorific value of a fuel will be the same (A) If its ash content is zero (B) If its carbon content is very low (C) If its hydrogen/hydrogen compound content is zero (D) Under no circumstances

Last Answer : (C) If its hydrogen/hydrogen compound content is zero

A liquid/gaseous fuel containing hydrocarbons and high amount of sulphur is burnt with 40% excess air. The flue gas still contains large amount of carbon monoxide. This may be due to the (A) Presence of large quantity of hydrogen in the fuel (B) Low calorific value of the fuel (C) High sulphur content in the fuel (D) Lack of thorough mixing of fuel with air

Description : A liquid/gaseous fuel containing hydrocarbons and high amount of sulphur is burnt with 40% excess air. The flue gas still contains large amount of carbon monoxide. This may be due to the (A) Presence of large ... fuel (C) High sulphur content in the fuel (D) Lack of thorough mixing of fuel with air

Last Answer : (D) Lack of thorough mixing of fuel with air

Washing of coal decreases its (A) Caking index (B) Mineral matter content (C) Ash content (D) Both (B) and (C)

Description : Washing of coal decreases its (A) Caking index (B) Mineral matter content (C) Ash content (D) Both (B) and (C)

Last Answer : (B) Mineral matter content

Which of the following statement (s) regarding India's coal reserves is/are true ? 1. Over 90 percent of total reserves are located in the valleys of Son, Damodar, Mahanadi and Godavari 2. Indian coal reserves are characterised by low ash content and high calorific value 3. India has limited prime coking reserves (a) I only (b) I and III (c) II and III (d) I, II and III

Description : Which of the following statement (s) regarding India's coal reserves is/are true ? 1. Over 90 percent of total reserves are located in the valleys of Son, Damodar, Mahanadi and Godavari 2. Indian coal reserves are characterised ... reserves (a) I only (b) I and III (c) II and III (d) I, II and III

Last Answer : Ans: (c)

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)

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

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

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

As the equilibrium moisture content of the coal increases, its (A) Calorific value increases (B) Swelling number decreases (C) Swelling number increases (D) Bulk density decreases

Description : As the equilibrium moisture content of the coal increases, its (A) Calorific value increases (B) Swelling number decreases (C) Swelling number increases (D) Bulk density decreases

Last Answer : (B) Swelling number decreases

With increase in moisture content of coal, its (A) Calorific value increases sometimes (B) Bulk density always decreases (C) Clinkering tendency during combustion increases (D) None of these

Description : With increase in moisture content of coal, its (A) Calorific value increases sometimes (B) Bulk density always decreases (C) Clinkering tendency during combustion increases (D) None of these

Last Answer : (D) None of these

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)

Low temperature oxidation of coal is accelerated by the (A) Storage in large heaps (B) Storage in compressed piles (C) Absence of porous or friable particles (D) All (A), (B) and (C)

Description : Low temperature oxidation of coal is accelerated by the (A) Storage in large heaps (B) Storage in compressed piles (C) Absence of porous or friable particles (D) All (A), (B) and (C)

Last Answer : (A) Storage in large heaps

Spontaneous combustion of coal on storage results due to(A) Inadequate ventilation (B) Low temperature oxidation (C) Storage in large heaps with small surface to volume ratio (D) All (A), (B) and (C)

Description : Spontaneous combustion of coal on storage results due to (A) Inadequate ventilation (B) Low temperature oxidation (C) Storage in large heaps with small surface to volume ratio (D) All (A), (B) and (C)

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

Coal tar fuels (CTF) as compared to petroleum based fuel oils have higher (A) Calorific value (B) Higher C/H ratio (C) Sulphur content (D) Difference in gross & net calorific value

Description : Coal tar fuels (CTF) as compared to petroleum based fuel oils have higher (A) Calorific value (B) Higher C/H ratio (C) Sulphur content (D) Difference in gross & net calorific value

Last Answer : (B) Higher C/H ratio

A coal gasifier operating at 20 atm. (e.g. Lurgi gasifier) as compared to one operating at atmospheric pressure (e.g. Kopper-Totzek or Winkler gasifier) will produce a gas having (A) Higher methane content and thus higher calorific value (B) Higher carbon monoxide content(C) Lower carbon dioxide content(D) None of these

Description : A coal gasifier operating at 20 atm. (e.g. Lurgi gasifier) as compared to one operating at atmospheric pressure (e.g. Kopper-Totzek or Winkler gasifier) will produce a gas having (A) Higher ... calorific value (B) Higher carbon monoxide content (C) Lower carbon dioxide content (D) None of these

Last Answer : (A) Higher methane content and thus higher calorific value

Bomb calorimeter can be used to determine the __________ of the coal. (A) Sulphur content (B) Calorific value (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : Bomb calorimeter can be used to determine the __________ of the coal. (A) Sulphur content (B) Calorific value (C) Both (A) & (B) (D) Neither (A) nor (B)

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

During its calorific value determination by bomb calorimeter, coal is combusted by (A) Air (B) Oxygen (C) Oxygen enriched air (D) None of these

Description : During its calorific value determination by bomb calorimeter, coal is combusted by (A) Air (B) Oxygen (C) Oxygen enriched air (D) None of these

Last Answer : (C) Oxygen enriched air

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

Initial pressure of oxygen introduced into the 'bomb' of the bomb calorimeter for determination of calorific value of coal/fuel oil may be around __________ atm. (A) 3-5 (B) 25-30 (C) 60-65 (D) 95-100

Description : Initial pressure of oxygen introduced into the 'bomb' of the bomb calorimeter for determination of calorific value of coal/fuel oil may be around __________ atm. (A) 3-5 (B) 25-30 (C) 60-65 (D) 95-100

Last Answer : (B) 25-30

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 in a by-product coke oven is about 16 hours (D) Gross and net calorific value of a fuel is the same, if it does not contain hydrogen or hydrocarbons

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

Presence of __________ in a dry gaseous fuel does not contribute to its calorific value. (A) Sulphur (B) Oxygen (C) Hydrogen (D) Carbon

Description : Presence of __________ in a dry gaseous fuel does not contribute to its calorific value. (A) Sulphur (B) Oxygen (C) Hydrogen (D) Carbon

Last Answer : (B) Oxygen

A fuel containing carbon and carbon monoxide (but containing no hydrogen or its compounds) is burnt in pure oxygen at constant pressure. Its gross calorific value as compared to net calorific value will be (A) More (B) Less (C) Same (D) Data insufficient; can't be predicted

Description : A fuel containing carbon and carbon monoxide (but containing no hydrogen or its compounds) is burnt in pure oxygen at constant pressure. Its gross calorific value as compared to net calorific value will be (A) More (B) Less (C) Same (D) Data insufficient; can't be predicted

Last Answer : (C) Same

Temperature of a furnace fired with low calorific value fuel gas (i.e. lean gas) can be increased by (A) Preheating the combustion air (B) Oxygen enrichment of combustion air (C) Preheating the fuel gas (D) All (A), (B) & (C)

Description : Temperature of a furnace fired with low calorific value fuel gas (i.e. lean gas) can be increased by (A) Preheating the combustion air (B) Oxygen enrichment of combustion air (C) Preheating the fuel gas (D) All (A), (B) & (C)

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

Softening temperature of coal ash is a measure of the __________ of coal. (A) Caking tendency (B) Coking tendency (C) Clinkering tendency (D) Size stability

Description : Softening temperature of coal ash is a measure of the __________ of coal. (A) Caking tendency (B) Coking tendency (C) Clinkering tendency (D) Size stability

Last Answer : (C) Clinkering tendency

Change of heat content when one mole of compound is burnt in oxygen at constant pressure is called the (A) Calorific value (B) Heat of reaction (C) Heat of combustion (D) Heat of formation

Description : Change of heat content when one mole of compound is burnt in oxygen at constant pressure is called the (A) Calorific value (B) Heat of reaction (C) Heat of combustion (D) Heat of formation

Last Answer : (C) Heat of combustion

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

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

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

Wind loss' resulting from unscientific storage of coal may be the order of about __________ percent. (A) 2.5 (B) 7.5 (C) 10.5 (D) 14.5

Description : Wind loss' resulting from unscientific storage of coal may be the order of about __________ percent. (A) 2.5 (B) 7.5 (C) 10.5 (D) 14.5

Last Answer : (A) 2.5