Process of combustion in boiler burners

When fuel is atomized in a burner, two types of droplets are formed. Very fine mist of lighter fractions and larger droplets of heavier fractions of residual fuel. Combustion in the burner is called a suspended flame, the rate at which particles entering is particles entering the flame is proportional to the rate at which particles are leaving. the actual flame remains suspended. The combustion zone can be divided into two zones, primary flame- the lighter particles are ignited quickly from the radiant heat from the flame and refractory quarl.. the primary flame will heat up the heavier particles and they get ignited at the secondary flame zone. The primary flame stability depends upon how we provide primary air, which provided by producing a vortex flow at the end of burner tip plate.this ensures good mixing of air and fuel, be reducing the speed forward and keeping primary flame within refractory quarl.