CO-incineration

'Co-incineration plant means a stationary or mobile plant whose main purpose is the generation of energy or production of material products and which uses wastes as a regular or additional fuel; or in which waste is thermally treated for the purpose of disposal. This definition covers the site and the entire plant including all incineration lines, waste reception, storage, an site pre-treatment facilities; its waste-, fuel- and air-supply systems; the boiler; facilities for treatment or storage of the residues, exhaust gas and waste water; the stack; devices and systems for controlling incineration operations, recording and monitoring incineration conditions (proposal for a council directive an the incineration of waste - 98/C 372/07). Waste incinerators primarily aim at rendering waste inert, at reduction of its volume and at the generation of energy from waste. The main aim of co-incineration an the other hand is either the recovery of energy from waste, the recovery of its material properties or a combination of the latter in order to save costs for primary energy. Two main groups of interest have lately been pushing waste towards co-incineration: conventional fossil fuels are getting increasingly scarce and hence expensive and generate carbon dioxide (greenhouse gas). The use of high calorific waste fractions is considered as an alternative. In many countries land filling of waste is subject to increasingly strict regulations in order to reduce environmental risk and landfill volume. The Austrian Landfill Ordinance for instance prohibits the disposal of untreated waste from the year 2004. Incineration seems to be the most effective treatment option to destroy organic matter. However the capacities of waste incinerators are limited, giving rise to a search for additional incineration capacity. The obvious advantages of co-incineration, such as the saving of fossil fuels and raw materials, the thermal treatment of waste fractions and possible economic benefits by accepting external waste as well as by saving treatment costs for internal waste, could be opposed by severe disadvantages: quantitative increase of emissions to air and water; qualitative deterioration of solid residues and emissions due to harmful waste components; dissipation of HMs in the environment; negative influence an product quality; negative image and lack of public acceptance of plant and product. In any case, waste use in industrial incineration should only be approved in special cases, under certain conditions and under continuous monitoring and control. (author)