Explanation:

These technologies are sometimes are known as Advanced Thermal Technologies or Alternative Conversion Technologies. They typically rely on carbon-based waste such as paper, petroleum-based wastes like plastics, and organic materials such as food scraps.

The waste is broken down to create gas, solid and liquid residues. The gases can then be combusted in a secondary process.The pyrolysis process thermally degrades waste in the absence of air (and oxygen).Gasification is a process in which materials are exposed to some oxygen, but not enough to allow combustion to occur. Temperatures are usually above 750oC. In some systems the pyrolysis phase is followed by a second gasification stage, in order that more of the energy carrying gases are liberated from the waste