NITROGEN OXIDECaused By Localised High Flame Temperature and an O2 rich Environment (in the Fire Ball) during Ignition of volatile matter.(Initial Stages of Combustion)EffectsContributes to SmogDepletes the OZONE Layer

NITROGEN OXIDETHERMAL NOXProduced From the Nitrogen Present in the Combustion AirAgents Responsible for Production of Thermal NOXIncreased Excess AirIncreased Flame TemperatureIncreased Time at High Temperature

NITROGEN OXIDEFUEL NOXProduced From the Nitrogen Compounds in the FuelResponsible for significant part of Total NOX ProducedCan form at much Lower Temperature than Thermal NOX

TECHNIQUES TO LOWER NOXOVER FIRE AIROFA Nozzles Divert approximately 20% of the total Combustion Air to a Burning Zone above the Fire BallIGNITION POINTBy moving the Ignition Point closer to the Coal Nozzles the Volatile matter will have more time to ignite before entering the Fire Ball

EFFECT OF OVER FIRE AIR ON NOX PRODUCTION