Question

In a large boiler with several burners, why is it desirable to balance burner performance? What analytical measurements are helpful?

Answer 1

In large boilers several burners are used in order to heat the fluids unifromly and efficiently. Its desirable to balance the burner performance because energy costs are a major factor for many industrial processes, it does makes sense to carefully analyze how fuel is being used and whether the burners are running at peak efficiency.

To improve the burner performance following analytical measurements are required:

• Excess Combustion Air

  It is defined as any air that is not necessary to burn all of the fuel, excess combustion air can rob boiler systems of efficiency. It takes energy to heat the excess air and most of this heat is lost. Better air management can lead to significant improvements.

• Air/Fuel Ratio

  By keeping tighter control of the air/fuel ratio, one can better control the combustion reaction and its efficiency. One method for doing this includes using a fixed-air system – also called fuel-only control – where airflow is held constant and the burner output is controlled by trimming incoming gas via a control valve. Another option is to control air input with a variable-frequency drive (VFD), regulating the blower speed with a single gas valve controlling gas inputs.

• Burners only create heat but how the heat transfers to the end product is a function of the specific equipment design.