Single stage denitration
AssigneeStudsvik, Inc.
InventorJ. Bradley Mason
Life of this patent
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Abstract
A system and method is described having a single reaction vessel (12) using superheated stream optionally augmented by oxygen for reducing nitrogen oxides present in a wide variety of organic compounds. Reduction takes place quickly when a stream/oxygen mixture is injected into a fluidized bed (22) of ceramic beads. Reducing additives are metered into the reaction vessel (12) and/or provide energy input to reduce nitrates to nitrogen. The speed of the fluidizing gas mixture agitates the beads that then help to break up solid wastes and to allow self-cleaning through abrasion thereby eliminating agglomerates, and the oxygen, when used, allows for some oxidation of waste by-products and provides an additional offset for thermal requirements of operation.
Claims105
A method for removing nitrogen oxide groups from waste material, said method comprising:
- providing a waste material comprising a nongaseous waste containing nitrogen oxide groups;
- providing a reaction vessel containing a fluidizable reaction bed and heating said reaction bed to an operating temperature;
- providing a fluidizing gas, at least one reductant and said waste material in said reaction bed wherein said fluidizing gas provides a gas velocity that agitates said waste material, fluidizes said reaction bed and elutriates fine solids from said fluidized reaction bed, wherein said fluidizing gas is provided in said fluidizable reaction bed via a fluidizing inlet, and wherein said waste material is provided in said fluidized reaction bed via a waste inlet;
- operating a first zone of said fluidized reaction bed under oxidizing conditions;
- and,
- operating a second zone of said fluidized reaction bed under reducing conditions so that said nitrogen oxide groups in said waste material are reduced at said operating temperature, thereby removing nitrogen oxide groups from said waste material and producing an inorganic residue and a gaseous effluent that together have substantially less nitrogen oxide groups than were present in said waste material.
A method for removing nitrogen oxide groups from waste material, said method comprising:
- providing a waste material comprising a nongaseous waste containing nitrogen oxide groups;
- providing a reaction vessel containing a fluidizable reaction bed and heating said reaction bed to an operating temperature;
- providing a fluidizing gas and said waste material in said reaction bed wherein said fluidizing gas provides a gas velocity that agitates said waste material, fluidizes said reaction bed and elutriates fine solids from said fluidized reaction bed, wherein said fluidizing gas is provided in said fluidizable reaction bed via a fluidizing inlet, and wherein said waste material is provided in said fluidized reaction bed via a waste inlet;
- operating a first zone of said fluidized reaction bed under oxidizing conditions;
- and,
- operating a second zone of said reaction bed under reducing conditions so that said nitrogen oxide groups in said waste material are reduced at said operating temperature, thereby removing nitrogen oxide groups from said waste material and producing an inorganic residue and a gaseous effluent that together have substantially less nitrogen oxide groups than were present in said waste material.
Dependencies are inferred from the claim text.