Gas Clean Up Systems

The main components of the gas clean-up plant are as follows:

  • Heat exchanger with dry cooler
  • Spark arrestor
  • Bag filter
  • ID fan
  • Mercury & Dioxin Filter

Heat exchanger
The heat exchanger is a double pass water jacket boiler designed to cool the exhaust gasses from the cremator to 150°C. The closed loop design includes a dry cooler within the system. The heat exchanger supplied with an automatic cleaning system which lowers the maintenance interval to only twice a year.

Spark Arrestor
The spark arrestor removes large particulate matter generally > 1 micron the flue gasses to protect the bag filter.

Bag Filter
The flue gasses, already cooled to 140°C, enter the bad unit, which consists of a number of cartridge filters to remove substantially all of the remaining particulate matter. It should be noted that this particulate matter collected in the filter unit is produced entirely from the cremation process and completely free of additives of any kind and such it does not require special treatment for disposal.


Other clean-up systems rely on the injection of carbon and lime or bicarbonate to react with the gases on the filter bags. The injection of such additives determines that the particulate matter collected on these bags be classed as a special waste and as such needs to be disposed of in a controlled and licensed manner.

ID Fan
The induced draught (ID) fan downstream of the bag filter unit draws the flue gases through the cremator, heat exchanger, spark arrestor and bag filter sections. The ID fan is operated as a variable speed unit and the inverter is controlled via a pressure transducer situated in the main chamber of the cremator.

The ID fan will ensure that a negative pressure is maintained within the main chamber of the cremator. The advantages of a variable speed drive unit over a conventional fixed speed fan are a reduction in noise and electricity consumption.

Mercury and Dioxin Filter Unit
The flue gas passes through the filter unit under positive pressure to ensure the gases pass through the complete filter and that no short-circuiting occurs. The filter unit is designed to ensure that mercury, dioxin and HCL will be removed from the flue gasses by leading the gasses through a bed of activated carbon and sodium bicarbonate.

After 2000 cremations the 700 Kg of activated carbon will changed with new filter material. The used material is regenerated and all contaminates removed, thus providing a complete environmental friendly recycling process. All crematoria will receive official recycling certificates by DFW Europe BV.