Co-incineration and Other Treatment Alternatives

Waste treatment alternatives to the classic waste management practices

In addition to the classic waste disposal facilities for waste management - such as sorting plants, plants for biological treatment, incinerators, mechanical-biological waste treatment plants and landfills - there are more and more possibilities for treating waste that are not originally included in the waste management system.

Co-incineration

Co-incineration of certain wastes in power and cement plants has been practised in Germany for quite some time now. This especially applies to the practise of burning old tyres in the cement industry, but is also commonly practised as the co-incineration of waste oil, paper sludge and sewage sludge. The Waste Incineration Directive 2000/76/EG was enacted to harmonise co-incineration as oppose to pure waste incineration, which was transposed into national law through the amendment of the 17 th article of the BImSchV (Federal Immission Control Ordinance) in 2003. The purpose of the harmonisation is to reduce environmental pollution as much as possible, particularly adverse effects on human health through air emissions.

The practise of co-incineration became a topic of greater interest for waste management when the Ordinance on Environmentally Compatible Storage of Waste (Abfallablagerungsverordnung) was implemented. Special considerations were given to adding the potential of a high calorific value fraction from a mechanical pre-treatment to this disposal route. For the year 2005 the available capacity of co-incineration was estimated at a total of 3.5 million tonnes by the federal states working group on waste. Other estimations on theoretically possible capacities amount to approximately 12 million tonnes. As to how available these capacities can actually be made strongly depends on the quality of refuse derived fuel, which must comply with the requirements of the burning processes in cement and power plants.

Not every waste is appropriate for co-incineration. Depending on the process, demands must be made on the calorific value, the homogeneity of the waste, but also on the maximum content of certain substances that would otherwise lead to undesirably high emissions.

Research done on co-incineration as oppose to mono-incineration of various kinds of waste has been and is being conducted at IFEU for different projects.

A comprehensive respective project on the situation in the federal state of North Rhine-Westphalia was finished at the end of 2007. One of the results show that the practice of thermal waste treatment in North Rhine-Westphalia makes for many of the considered impacts a positive contribution, of which mono-incineration and co-incineration each contribute in different degree. Both approaches have specific advantages as well as optimisation potentials (referring to the single plant), so that the combination of both makes possible a total optimisation of thermal waste treatment. Essential element is the incinerator.

Symposium "Beitrag der Abfallwirtschaft zum Klimaschutz Duisburg BEW" 26.10.2007 (pdf 930 KB) in German

Short Version of the Study (pdf 1,4 MB) in German

Long Version of the Study (pdf 7,4 MB) in German

Other treatment alternatives

In addition to co-incineration of waste in cement and power plants, there are also other types of co-treatment in facilities aside from the classic waste management system. These include e.g. the co-treatment of biogenic waste in digestion tanks not being used at full capacity in sewage treatment plants.

For this type of waste disposal, not only questions concerning the ecological sense arise, but basic questions on the technical and legal feasibility of such procedures. Sewage plants must principally comply with water laws, and co-treating waste may in no way oppose with the ban of deterioration of water (Verschlechterungsverbot) according to § 1a of the Water Management Act (WHG). The federal state of North Rhine-Westphalia has extensively researched how certain wastes can still be suitable for co-treatment and may get a permit. The resulting findings were compiled in a leaflet. Furthermore, the results were published in a series of the MUNLV NRW "Reports on Environment - Waste Water", volume 22.

Projects

Questions concerning co-incineration apply for one to the characteristics of a waste that need to comply with the concrete process requirements, as well as that co-incineration needs to prove to be more environmentally friendly in the sense of the Closed Substance Cycle Waste Management Act ( KrW-/AbfG ) compared to other alternatives. These questions were and are being investigated at IFEU in various projects. A few of our projects involving co-incineration as well as co-treatment can be found here (in German).

Contact

Horst Fehrenbach (06221/ 4767-16; horst.fehrenbach@ifeu.de)
Florian Knappe (06221 / 4767-26; florian.knappe@ifeu.de)
Regine Vogt (06221 / 4767-22; regine.vogt@ifeu.de)