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US 4,793,270 AGranted
Incineration of waste materials
AssigneeUniversity of Waterloo
InventorsFrancis W. Karasek, Leslie C. Dickson, Otto Hutzinger
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Abstract
In the conventional incineration of solid waste materials, flyash present in the combustion products gas stream catalyzes the formation of toxic dioxins from chlorinated organic materials. By providing a catalyst poison, such as carbon disulphide, in association with the flyash, typically by spraying onto the solid wastes prior to incineration, the catalytic effect is decreased, resulting in decreased dioxin formation.
Claims15
A method of disposal of solid refuse in the form of municipal waste containing materials which are combustible to form precursors for dioxin formation,
- which comprises incinerating said solid refuse in a self-sustaining incineration operation to form gaseous products of incineration containing fly ash and precursors for dioxin formation,
- passing said gaseous products of incineration to a precipitation step wherein said fly ash is precipitated from the gaseous products of incineration,
- contacting the surface of said fly ash during said passage of said gaseous products of incineration to said precipitation step with a small quantity of at least one catalytic-effect inhibiting substance capable of being adsorbed on and reacting with catalytically-active sites on the surface of the fly ash to form stable, inactive surface compounds, so as to inhibit catalytic effects of said fly ash towards the formation of dioxins from said precursors during said passage, and
- venting said gaseous products of incineration after said precipitation of fly ash therefrom.
1 more element
Dependencies are inferred from the claim text.