Dioxins and furans include over 200 compounds that can basically be described as chlorine-containing hydrocarbons of varying toxicity. They do not occur in nature, but are unwanted side products of all kinds of combustion processes.

 
The emission of dioxin has been reduced continuously over the past ten years. Reasons for this achievement include the optimisation of operating conditions, the development of more effective flue gas cleaning methods in conjunction with higher incineration temperatures. Dioxins and furans are destroyed at temperatures above 900°C. Complete burn-up of flue gases is therefore a considerable contribution to minimisation of dioxin/furan emissions.
 
Emissions can also be reduced significantly by favourable management of the flue gases. This means getting the flue gases beyond the critical temperature of 900°C as quickly as possible without the gases cooling off in the process, because cooling off could be associated with new formation of pollutants.
 
A residence time of at least two seconds at 850°C is prescribed by law for the gases. Thermoelements at the end of the first pass monitor adherence to this value. Further flue gas cleaning components downstream avoid the emission of any newly formed dioxins.