I.C.F.&WELKO: the new burner to recover energy lost to the wall

New-generation roller kilns generally adopt a multiplicity of closely spaced burners of relatively low thermal capacity and highly uniform heat distribution over the products undergoing firing. The use of multiple burners obviously impacts negatively on the system's heat consumption in that each burner represents a thermal bridge between the firing chamber and the external wall.

In order to limit heat losses, I.C.F.&WELKO has developed a new burner whose key characteristic is the ability to recover energy lost to the wall and reuse it to reheat the combustion air introduced into the burner. The result is a superior combustion performance compared to the use of hot air at 120°C. The highest efficiency is obtained with a capacity of between 10 and 15 Mcal/h.

Furthermore the use of air at 120°C (recovered from indirect kiln cooling) instead of air at 20°C increases performance by a further 5%, resulting in an efficiency curve that is equal to the sum of the two existing curves. Further advantages are the significant lower production of NOx compared to conventional burners (see table) and the 30-50% lower production of CO (see table).