Thermal Processing is a waste treatment process that involves the combustion of organic substances contained in waste materials. Thermal Processing of waste materials converts the waste into ash, flue gas and heat. In some cases, the heat generated by thermal processing can be used to generate electric power.

Thermal Processing with energy recovery is one of several waste-to-energy (WtE) technologies such as gasification, plasma gasification, pyrolysis and anaerobic digestion. Thermal Processing may also be implemented without energy and materials recovery.

Incinerators reduce the mass of the original waste by 72-80% and the volume by 90 %, depending on composition and degree of recovery of materials such as metals from the ash for recycling.


This means that while thermal processing does not completely replace landfilling, it significantly reduces the necessary volume for disposal. Garbage trucks often reduce the volume of waste in a built-in compressor before delivery to the incinerator.

Denmark and Sweden have been leaders in using the energy generated from incineration for more than a century, in localised combined heat and power facilities supporting district heating schemes. In 2005, waste thermal processing produced 4.8 % of the electricity consumption and 13.7 % of the total domestic heat consumption in Denmark.A number of other European countries rely heavily on thermal processing for handling municipal waste, in particular Luxembourg, the Netherlands, Germany and France.

Waste-to-Energy Plants

Maishima, Japan
After a visit to Vienna’s Spittlelau WTE plant, the Mayor of Osaka decided that the city’s new WTE plant should also have an exterior treatments designed by Austrian artist Friedensreich Hundertwasser. The plant handles about 900 tpd of MSW and is built on a man-made island.

Spittelau, Austria
The plant exterior treatments were designed by renowned Austrian artist Friedensreich Hundertwasser and implemented by Architekten Marchart, Möbius & Partner. The plant handles about 1,200 tpd of MSW with most thermal output used for Vienna’s district heating system.