White flue gas (resembling steam) coming out of the chimney of a
thermal power plant indicates that the fuel used in the boiler furnace is
(A) Tar
(B) Coke oven gas
(C) Pitch
(D) Pulverised coke

1 Answer

Answer :

(B) Coke oven gas

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Last Answer : (B) Pulverised coking coal

Description : Black smoke coming out of the chimney of a furnace is an indication of the use of __________ in the furnace. (A) Low amount of excess combustion air (B) Large quantity of excess combustion air (C) Hydrocarbon fuel (D) Pulverised coal as fuel

Last Answer : (A) Low amount of excess combustion air

Description : Fuel used in B.F. stove is (A) Pulverised coal (B) Furnace oil (C) Blast furnace gas/mixed gas (D) Coke oven gas

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Last Answer : (B) Very high excess air

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Last Answer : (D) High pressure boiler

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Last Answer : (B) A bag filter incurs very small pressure drop and is very efficient for removal of submicronic dust particles from flue gases at very high temperature

Description : In practical operation of any furnace, zero oxygen percentage or theoretical CO2 percentage in flue gas is rarely achieved, because of (A) Use of non-preheated combustion air (B) Use of pulverised solid ... of fuel & air and infiltration of air (D) Use of excessive positive draft in the furnace

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Description : Pitch creosote mixture (PCM) as compared to furnace oil is a better fuel, because its (A) Emissivity factor is higher (B) Sulphur content is lower (C) Flue gas has lower dew point thereby facilitating more waste heat recovery (D) All (A), (B) and (C)

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

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Last Answer : Ans: Economizer

Description : Which of the following will be unsuitable for dust cleaning from flue gas at 400°C from a pulverised coal fired boiler? (A) Multicyclones (B) Bag filter (C) Wet scrubber (D) Hydrocyclones

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Last Answer : (B) 10

Description : Oxygen percentage in the flue gas coming out of a gaseous fuel fired furnace should be ideally about __________ percent. (A) < 2 (B) < 5 (C) < 8 (D) < 10

Last Answer : (A) < 2

Description : Coke oven walls are lined with __________ bricks. (A) Silica (B) Tar-dolomite (C) Low thermal conductivity (D) Fire clay

Last Answer : (A) Silica

Description : Which furnace employs natural draft? (A) Coke oven (B) Boiler (C) Rotary kilns (D) L.D. converter

Last Answer : (A) Coke oven

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Last Answer : A]Increase thermal efficiency of boiler

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Last Answer : (C) 150

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Last Answer : (A) Blast furnace gas

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Description : Which of the following is not a by-product fuel? (A) Producer gas (B) Blast furnace gas (C) Coke oven gas (D) Refinery gas

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Description : Which of the following is a poisonous fuel gas? (A) Coke oven gas (B) Blast furnace gas (C) Natural gas (D) None of these

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Last Answer : b) Dry flue gases

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

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Last Answer : (D) Natural draft

Description : Hard pitch is used for making (A) Pulverised fuel (B) Perfumes (C) Insecticides (D) Plastics

Last Answer : (A) Pulverised fuel