What remains after solid waste is combusted?

When solid waste undergoes combustion, the primary outcome is the transformation of solid materials into gases and residual matter. The correct answer identifies ash residue as a significant byproduct of this process.

During combustion, organic materials in the waste burn off, resulting in gaseous emissions such as carbon dioxide, water vapor, and other pollutants. However, not all components of the waste combust completely. Certain inorganic materials, like metals, glass, and ceramics, do not combust and instead remain as solid ash after the process. This ash residue can accumulate at the bottom of the combustion chamber and can contain various materials that were present in the original waste.

Understanding ash residue is crucial in waste management and environmental health, as it can have implications for disposal methods and potential recycling. The management of ash is an important part of waste-to-energy strategies, as it needs to be handled and disposed of safely to mitigate environmental impacts.