FUELS AND COMBUSTION QUIZ

For every 10% increase in the excess air; the fuel consumption increases by __________ percent.

5

2

0.1

10

TRUE ANSWER : ?
YOUR ANSWER : ?

Main constituents of benzol are

Anthracene & phenol

Tar & creosote

Ammonia & phenol

Benzene, toluene & xylene

TRUE ANSWER : ?
YOUR ANSWER : ?

Which of the following has the highest flame velocity?

C₂H₆

CO

CH₄

H₂

TRUE ANSWER : ?
YOUR ANSWER : ?

Which of the following gaseous fuels is likely to have the highest gross calorific value?

LPG

Natural gas

Producer gas

Sewage gas

TRUE ANSWER : ?
YOUR ANSWER : ?

A carbonaceous fuel (containing no H₂ or hydrocarbons) is burnt and the resulting flue gas contains 21% CO₂. It means that

Complete combustion of fuel has taken place

21% excess air has been used for combustion

No excess air has been used for combustion

21% excess oxygen has been used for combustion

TRUE ANSWER : ?
YOUR ANSWER : ?

Very __________ coals are completely devoid of cokability i.e, it is non coking.

Young

Mature

Neither A nor B

Both A & B

TRUE ANSWER : ?
YOUR ANSWER : ?

Blast furnace gas compared to coke oven gas has

Narrower limit of inflammability

Lower ignition temperature

Higher calorific value

Lower theoretical flame temperature

TRUE ANSWER : ?
YOUR ANSWER : ?

The main function of primary air in pulverised coal fired burner is to

Burn CO to CO₂

Have proper combustion by supplying it around the burner

Dry and transport the coal

Preheat the tertiary air used for complete combustion of CO to CO₂

TRUE ANSWER : ?
YOUR ANSWER : ?

If the specific heat of gaseous products of combustion of a fuel is high, the abiabatic flame temperature will be

Low

None of these

Very high, if the fuel is of low calorific value

High

TRUE ANSWER : ?
YOUR ANSWER : ?

Light oil whose major component is benzol, is obtained by the distillation of crude tar in the temperature range of __________ °C.

280-300

200-300

250-270

80-170

TRUE ANSWER : ?
YOUR ANSWER : ?

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