FUELS AND COMBUSTION QUIZ

21% excess oxygen has been used for combustion

No excess air has been used for combustion

21% excess air has been used for combustion

Complete combustion of fuel has taken place

Resistance to impact breakage

Abradability

Swelling characteristics

Agglutinating properties

65

30

120

180

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

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

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

Coke oven gas

Producer gas

L.D. converter gas

Blast furnace gas

Producer gas

Natural gas

Sewage gas

LPG

Low forced draught and fuel bed temperature

Low reactivity of carbonised residue containing high proportions of iron & sulphur

Thick fire bed and preheated primary air

All of these

Liptinite

Clarain

Micrinite

Fusinite

Dry the coal

Transport the coal to the burner

Ensure efficient burning of coal around the burner

Reduce primary air requirement

Endothermic

None of these

Auto catalytic

Exothermic