Burnermax

Examples

Excess Air Control with a Trim Flap

The boiler shown here is a thermal oil heater installed at a German particle board factory with a thermal capacity of 4.8 MW. The average boiler load approx. 60 %. Annual fuel cost are in the order of € 700,000.

Even as the burner was maintained and optimized by a works service technician immediately before the installation of the BurnerMax the flue gas oxygen fluctuated considerably between 3.8 and 5.4 %. The average value observed was 4.8 % Oxygen. With an average measured flue gas temperature of 288 ºC the flue gas loss can be calculated to be 13.65 %.

After installing the BurnerMax the boiler was operated as before. Typical flue gas oxygen levels are shown here. To reduce the flue gas heat loss, the burner was equipped with an air trim flap. The BurnerMax controller uses this flap to minimize the flue gas oxygen. The Wiring Diagram is shown here. The flap is mounted in a distance to the inlet duct, so only a partial air flow is modulated and higher oxygen levels during very low load conditions are achieved to ensure flame stability. The flap opens automatically fully if fault conditions exist (Alarms) or even if the BurnerMax controller fails completely.

A spring loaded flap option is also available which will open also under complete power failure. During the following controlled operation a set point of 1.8 % oxygen was selected. The recorded flue gas oxygen was 1.5 - 2.2 % with an average of 1.7 % oxygen. The calculated flue gas loss became then 11.18 %, which is a reduction of flue gas loss by 18.1 %, hence 2.8 % fuel is saved.