main characteristics

Metal fibre burner (MFB)

Metal fiber burners are typically used in applications where uniform heating of the product by infrared radiation is advantageous. Both the burner output and the emitted radiant heat can be controlled over a wide range. The reaction times of metal fiber burners are just a few seconds. This allows the temperature curve required for an optimum heating process of the workpiece to be precisely and reproducibly achieved. The risk of overheating of the product is drastically reduced. Short heating times and low excess air increase the energy efficiency of the heated process plants. Due to the simple cutting of the surface material used, even complicated burner shapes can be realized. The power range in which metal fiber burners are used extends from a few kilowatts to several megawatts. Metal fiber burners can be operated with natural gas, LNG, biogas, methane, ethane, propane, butane, lean gas or also with hydrogen/methane mixtures.

Application examples

• powder coating, surface treatment • drying process • tool heating • welding preheating • boiler heating • thermal exhaut gas treatment • coffee roasting • surface browning of baked products

Metal fibre surface

The burner surface of the metal fiber burner is made of Bekinit®. DThe uniquely knitted 3D material is made of highly heat-resistant Fecralloy® metal fibre and can be used as a curved, cylindrical or flat burner surface. The flexible structure of the material reduces the thermal shock susceptibility of the burners. The processing of the long-term stable fiber leads to a reliable radiant heat output with simultaneous high power modulation.

Radiant operation

An approx. 1 mm thin, barely visible flame carpet stabilizes over the burner surface, which is evenly permeated by the fuel gas/air mixture. Due to the high temperature gradient in the flame, heat is transported against the direction of flow towards the burner surface. The transferred heat causes the burner surface to glow. The temperature of the burner surface depends on the type of fuel gas, the excess air and the burner capacity. The maximum radiation intensity of the metal fibre burner depends on the surface temperature and ranges between 2,2  m – 3,3  m. Properties in radiant mode Spec. surface load: 100 - 500 kW/m² Maximum radiation efficiency: ca. 40 % air exces ratio: 1,1 - 1,5 burner surface temperature: 600 °C – 1050 °C Furnace and plant temperature: < 400 °C

Blue flame operation

If the specific area output exceeds 650 kW/m², the distance between the flame carpet and the burner surface increases. The heat transport from the flame to the burner surface is greatly reduced and the temperature of the burner surface drops significantly. The flame length can be a few centimetres in this operating condition. Typical for premixed flames is the bluish colour. Properties in blue flame mode Spec. surface load: 650 – 10.000 kW/m² air exces ratio: 1,1 -1,5 burner surface temperature: < 150 °C Furnace or plant temperature: < 800 °C