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

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
by

1 Answer

Answer :

(C) Is a measure of its size stability, when stored & exposed to weather
by

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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

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Last Answer : (C) 22

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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

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Last Answer : (A) 1100

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Last Answer : (D) None of these

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Last Answer : (C) Accelerates the burning rate and economises on fuel combustion

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Description : A good quality coal should have (A) Low fusion point of ash (B) High ash content (C) High sulphur content (D) None of these

Last Answer : (D) None of these

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