FUELS AND COMBUSTION QUIZ

Coking coal

Pulverised coal

Non-caking coal

Caking coal

Reduces its sulphur and ash content

All of these

Controls its ash fusibility and increases its calorific value

Improves its coking properties

1

5

2

3

H₂

CH₄

CO

C₂H₆

Lower calorific value at constant pressure

Higher calorific value at constant volume

Gross calorific value at constant pressure

Net calorific value at constant volume

Natural gas

Sewage gas

Blast furnace gas

Coke oven gas

6500

2500

4000

10000

Flue gas temperature

Flame temperature

Any of the above

Amount of heat liberated

Partial combustion of coal

Partial combustion of large size (< 50 mm) coke

Atmospheric pressure gasification of coal (e.g., in Kopper-Totzek gasifier)

High pressure gasification of coal (e.g. in Lurgi gasifier)

Low carbon conversion efficiency is achieved

Entrainment of solids is higher

Coking coals cannot be used

Larger quantity of coal can be processed