Hot-gas candle-filters

Hot gas candle filter for temperatures up to 1000° C (1832° F)


Early dust removal at high temperatures from particle-contaminated waste gases is not only more economical but also much more ecological since the cooling and subsequent re-heating required for filtering is often unnecessary.

Conventional filter media made of synthetic fibres reach their limits at gas temperatures above 260°C (500 °F) due to their insufficient temperature resistance and flammability. 

Our hot gas filters are used for waste gas temperatures above 250 °C (482 °F) and replace the conventional textile filters like bag house filters. The cooling of the waste gases to the operating temperature of the bag house filter is no longer necessary and therefore, in many cases, enormous energy savings are made. Our hot gas candle filters can be used up to 1000 °C (1832 °F).

Advantages of hot gas candle filters:

  • Wide range of operating temperature 250 °C (482 °F) to 1000 °C (1832 °F)
  • Energy-saving by recycling of thermal energy of the exhaust gas
  • Increase of the overall efficiency
  • Prevention of re-heating the exhaust gas
  • Protection of down streamed components like recuperator, catalysts
  • Operation above dew points for acid gases, thus minimizing corrosion
  • Separation of incandescent particles

Hot gas filters are cleaned either according to their degree of contamination (by monitoring the pressure difference, i.e. pressure-controlled) or after a certain time (time-controlled) by introducing a short compressed air pulse into the filter bags against the direction of flow ("pulse jet cleaning") or by reversing the direction of flow in the filter system ("reverse air cleaning").

This causes the filter cake to be thrown off the filter cartridges and the filter material to become permeable again for an extended period. The dust falling from the filter candles is collected in hoppers and removed from the system by tubular screw conveyors or rotary valves and then disposed of or added to the following processes (e.g. firing, cement production).


We are looking forward to consulting you in the conception, planning and dimensioning of hot gas filter plants. Please contact us if you are interested in receiving more information.