• ENE-C-9
  • 燃燒處理系統
  • 減少使用過量空氣
  • Excess air can be minimised by adjusting the air flowrate in proportion to the fuel flowrate. This is greatly assisted by the automated measurement of oxygen content in the flue-gases. Depending on how fast the heat demand of the process fluctuates, excess air can be manually set or automatically controlled. Too low an air level causes extinction of the flame, then re-ignition and backfire causing damage to the installation. For safety reasons, there should therefore always be some excess air present (typically 1 – 2 % for gas and 10 % for liquid fuels).


  • As excess air is reduced, unburnt components like carbonaceous particulates, carbon monoxide and hydrocarbons are formed and may exceed emission limit values. This limits the possibility of energy efficiency gain by reducing excess air. In practice, excess air is adjusted to values where emissions are below the limit value.


  • The minimum excess air that is reachable to maintain emissions within the limit depends on the burner and the process.
    Note that the excess air will increase when burning solid wastes. However, waste incinerators are constructed to provide the service of waste combustion, and are optimised to waste as fuel.


  • The choice of fuels is often based on cost and may also be influenced by legislation and regulations.


  • Energy Efficiency (2009) 3.1.3