Page 17 - Waste-to-Energy in the Danube Strategy Region. Challenges and Prospects

Figure 4. Municipal solid waste treatment techniques and their products (Kumar and Samadder 2017)

Pyrolysis and gasification are less common due to their weaker commercial viability at

larger scales as compared to incineration. In the case of pyrolysis, the resulting products are in

general pyrolysis gas, oil and char; however, the specific products and their respective yields and
qualities depend on the specifics of the process (e.g. heating rate, temperature) and of the waste

(e.g. composition, particle size). Furthermore, certain types of waste are most suitable for pyrolysis,

including plastic, tires, waste electrical and electronic equipment, and wood waste. Although

relatively less common, commercially operating pyrolysis plants have been built, for example, in
Burgau and Hamm, Germany (Kumar and Samadder 2017). The Burgau plant, however, is no

longer in operation, having shut down at the turn of 2015/2016 (Bayerisches Landesamt für

Umwelt 2018). Thus the commercial viability of this technology remains in doubt.

Gasification is the process of converting organic waste into so-called syngas under
controlled atmospheric conditions (i.e. oxygen levels) and at high temperatures. The resulting

syngas can then be combusted to produce energy or be used as a feedstock for chemicals and

liquid fuel. Like pyrolysis, its use tends to be limited to smaller scale processing of MSW. The
smaller economies of scale of these two technologies can be seen as a weakness relative to

Project co-funded by the European Union
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