The document discusses combustion processes and calculations for determining air requirements and heat balances. It provides examples of calculating the air requirement in kilograms per tonne of waste for complete combustion of a given waste formula. Another example determines the heat balance and types of losses when combusting 100 tonnes per day of solid waste with a given composition, entering air and residue temperatures.

1. Combustion Process

2. Combustion Calculation
• Conservation of mass
• Conservation of energy
• Gas Law
• Law of combining masses

3. Air Requirement
• C + O2  CO2
(12) (32) (44)
• 2H2 + O2  2 H2O
(4) (32) (36)
• S + O2  SO2
(32) (32) (64)

4. Example
Determining air requirement for complete Combustion
Determine the air requirement expressed in kilogram per tonne of
waste for the complete oxidation of waste with formula
C(50)H(100)O(40)N

5. Determining combustion heat balance
• Determine heat available in exhaust gas from combustion of 100 tonnes/d of
solid waste with energy content of 10.500kJ/kg and following composition(% by
mass).
• Carbon- 28
• Hydrogen-5
• Oxygen-22
• Nitrogen-4
• Sulfer-1
• Water-20
• Inert-20
• Assume incinerator residue contain 5% carbon and temperature entering air and
residue from the grate are 25C and 425 C, respectively.

6. Type of losses
Reactor
• Unburned carbon
• Radiation
Latent heat
• Inherent moisture
• Moisture from bound water
• Moisture from oxidation of net hydrogen
Sensible heat
• In residue
• Stack gases