Definition o Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials.[11 "thermal treatment". o Incineration of waste materials converts the waste into ash,flue gas,and heat. o The ash is mostly formed by the inorganic constituents of the waste,and may take the form of sol id lumps or particulates carried by the flue gas.Definition  Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials.[1]  "thermal treatment".  Incineration of waste materials converts the waste into ash, flue gas, and heat.  The ash is mostly formed by the inorganic constituents of the waste, and may take the form of solid lumps or particulates carried by the flue gas