FUELS AND COMBUSTION QUIZ

Caking index

Swelling index

Gray-king index

Thickness of plastic layer

4000

1000

8000

6000

No by-products

Soft coke

Very low calorific value coke oven gas

Metallurgical coke

None of these

Protects the volatile products from pyrolysis (cracking) in the presence of hot coke and hot oven walls

Reduces the coking time

Increases the loss of fine coal dust from the ovens when charging

Use of preheated primary air

Use of thick fire bed

All of these

Low fusion point of ash (< 1100° C)

Absence of porous or friable particles

Storage in compressed piles

All of these

Storage in large heaps

H₂

CH₄

CO₂

NH₃

Water gas

Carburetted water gas

Blast furnace gas

Coke oven gas

5

15

50

25

Sulphur content

Type (solid, liquid or gaseous)

Ignition temperature

Calorific value