10.4  Thermal processing methods

Thermal processing of waste means heating waste so that it burns. During the burning (also known as combustion) process, the combustible material is converted into gases (mainly carbon dioxide and water vapour) and an ash residue. Thermal processing leads to a large reduction in the volume of solid material left over for landfill disposal and destroys pathogens, so it may look like an attractive option. However, unless the combustion takes place under tightly controlled conditions using equipment designed to prevent and capture any pollutants produced, the process will emit a large amount of smoke and other invisible air pollutants that can cause serious health problems.

There are two main thermal processes you may come across: open burning; and incineration. There are other more advanced thermal processing methods but these are not currently used in Ethiopia.