The fuel has an influence on the combustion efficiency.
At complete combus- tion, carbon dioxide (CO2) and water (H2O) are formed. An incorrect mixture of fuel, type of heating system, and introduction
of air may result in an unsatisfactory utilisation of the fuel and a consequent undesirable environmental effect.
An efficient combustion requires
• High temperature
• Excess oxygen
• Combustion time
This ensures a low emission of carbon monoxide (CO), hydrocarbons, polyaromatic hydrocarbons (PAH), and a small
amount of unburned carbon in the slag.
Unfortunately, these conditions (high temperature, a high amount of excess air, long combustion time) are also directly related to the formation of NOx.
The technology applied should therefore be a so-called “low-NOx” technology, i.e.,a technology applying methods resulting in a reduced NOx emission.
In addition to CO2 and H2O, the flue gas will contain air (O2 , N2 and Ar) and a high or low amount of undesirable reaction products, such as CO, hydrocarbons, PAH, NOx etc.