Primary and secondary burners: Separate electrically spark-ignited primary burners and secondary burners with automatic control shall be used to achieve the specified temperature requirements in the primary and secondary chambers. The flames of the primary and secondary burners shall not impinge on the incinerator walls or floor.
The primary combustion chamber must:
1. Be accepted as the primary combustion zone.
2. Be equipped with a burner/s burning gas/fuel or low sulphur liquid fuels.
Other combustion methods will be judged on merits.
3. Ensure primary air supply is controlled efficiently
Ensure minimum exit temperature is not less than 850oC
Air supply: Air supply in the primary and secondary chamber should be regulated between 30%-80% and 170%- 120% of stoichiometric amount respectively. Suitable flow measurement devices shall be provided on the primary and secondary air ducting. The combustion air shall be supplied through a separate forced draft fan after accounting for the air supplied through burners.The secondary combustion chamber must:
1. Be accepted as secondary combustion zone.
2. Be fitted with secondary burner/s burning gas or low sulphur liquid fuel or any suitable fuel.
3. Ensure secondary air supply is controlled efficiently.
4. Ensure flame contact with all gases is achieved.
5. Ensure residence time is not less than two (2) seconds.
6. Ensure the gas temperature as measured against the inside wall in the secondary chamber & not in the flame zone, is not less than 1100oC.
7. Ensure the oxygen content of the emitted gases is not less than 11%.
Ensure both primary and the combustion temperatures are maintained until all waste has been completely combusted
lnsulation: lnsulation to be used for masonry, reinforced concrete, or non-combustible material shall prevent damage to the foundation from excessive heat and shall be of a thickness to limit the outer casing to a maximum temperature of 66°C in an ambient temperature of 21°C when the incinerator is operating at full capacity.
Refractory: Refractory shall be #super duty# and heat-resistant to a minimum of 1100°C in the primary chamber and 1250°C in the secondary chamber. Refractory shall also be abrasion resistant in the prlmary chamber, constructed of plastic or castable type refractory, designed to prevent bulging and destruction due to heat stress, capable of supporting more than twice the hourly burning rate and preventing leakage of fluids, and with a minimum thickness of 11O mm for walls and hearths