FUELS AND COMBUSTION QUIZ

Is a measure of its size stability, when stored & exposed to weather

Gives an idea of the fusion temperature of ash

Is a measure of its caking tendency

Is related to its calorific value

High fusion point of its ash

Low ignition temperature

Very little ash content

Low adiabatic flame temperature

Pulverised coal in boilers

Less air for combustion

Correct amount of air for combustion

Too much air for combustion

Oxygen enriched air

Oxygen

Air

None of these

None of these

Higher carbon monoxide content

Lower carbon dioxide content

Higher methane content and thus higher calorific value

Yield of ammonia present in coke oven gas

Free carbon content in tar

Yield percentage of coke

Difference in gross & net calorific value of the coke oven gas

It is abrasive to the coal pulveriser (ie.g. ball mill) and the combustion chamber

The ash retains the sulphur & phosphorus and thus affects the quality of products in metallurgical furnace apart from increasing the slag volume. Besides, it may fuse and stick to the boiler tubes

All of these

The ash in molten condition gets absorbed in the pores of the refractory lining of the furnace and causes its spalling due to different co-efficient of expansion/contraction of the refractory and the

Octane number

Calorific value

Specific gravity

Viscosity

Ash

Iron

Moisture

Volatiles

CO + H₂O ⟷ CO₂ + H₂

C + 2H₂O ⟷ CO₂ + 2H₂

2CO ⟷ C + CO₂

C + H₂O ⟷ CO + H₂