What does ash residue refer to in waste management?

Ash residue pertains to the solid material that remains after the combustion of combustible waste. When materials are burned, the organic components are consumed in the combustion process, resulting in ash as a byproduct. This ash can consist of non-combustible minerals and other materials that were part of the original waste. Understanding ash residue is essential in waste management, especially regarding its handling, disposal, and potential recycling. Ash may require specific management practices to mitigate environmental impact, as it can contain heavy metals or other pollutants depending on the nature of the original waste.

The other options refer to different forms of waste management materials. Organic matter left after decomposition involves the breakdown of biodegradable materials, remaining liquid waste pertains to waste that has gone through some treatment but still contains liquid components, and untreated waste found in landfills refers to solid waste that has not undergone any processing. Each of these options highlights a distinct type of waste or byproduct, but they do not capture the definition of ash residue accurately.