FUELS AND COMBUSTION QUIZ

Calorific value of coke oven gas is less

Coke oven gas yield is more

Tar yield is less but free carbon in tar is more

All of these

All of these

Hard semi-coke starts shrinking at 600°C

Evolution of H₂ and formation of methane and aromatics occur at > 700°C

All tar is evolved at < 600°C

Back draughting

Banking

None of these

Under pressurising

More than theoretically required amount of air

Theoretically required amount of oxygen

Theoretically required amount of air

Less than theoretically required amount of air

750

1150

550

950

Pulverised coke

Coke oven gas

Pitch

Tar

Suppresses the discharge of fine dust and grit into atmosphere

In a metallurgical furnace does not contaminate the product in the furnace by ash from fuel

Requires larger combustion chamber than rich gaseous fuel

All of these

Use of preheated primary air

Use of thick fire bed

All of these

Low fusion point of ash (< 1100° C)

Ash

Moisture

Sulphur (4-6%)

Volatile matter

50

5000

5

500