Hybrid process for nitrogen oxides reduction
This patent describes a process for reducing the nitrogen oxide concentration in the effluent from the combustion of a carbonaceous fuel. It comprises introducing into the effluent a first treatment agent comprising a nitrogenous composition selected from the group consisting of urea, ammonia, hexamethylenetetramine, ammonium salts of organic acids, 5- or 6-membered heterocyclic hydrocarbons having at least one cyclic nitrogen, hydroxy amino hydrocarbons, NH{sub 4}-lignosulfonate, fur-furylamine, tetrahydrofurylamine, hexamethylenediamine, barbituric acid, guanidine, guanidine carbonate, biguanidine, guanylurea sulfate, melamine, dicyandiamide, biuret, 1.1{prime}-azobisformamide, methylol urea, methylol urea-urea condensation product, dimethylol urea, methyl urea, dimethyl urea, calcium cyanamide, and mixtures thereof under conditions effective to reduce the nitrogen oxides concentration and ensure the presence of ammonia in the effluent; introducing into the effluent a second treatment agent comprising an oxygenated hydrocarbon at an effluent temperature of about 500{degrees} F. to about 1600{degrees} F. under conditions effective to oxidize nitric oxide in the effluent to nitrogen dioxide and ensure the presence of ammonia at a weight ratio of ammonia to nitrogen dioxide of about 1:5 to about 5:1; and contacting the effluent with an aqueous scrubbing solution having a pH of 12 or lower under conditions effective to cause nitrogen dioxide to be absorbed therein.
- Assignee:
- Fuel Tech, Inc., Rowayton, CT (USA)
- Application Number:
- PPN: US 7-395810
- OSTI ID:
- 5804258
- Resource Relation:
- Patent File Date: 18 Aug 1989
- Country of Publication:
- United States
- Language:
- English
Similar Records
Mulit-stage process for reducing the concentration of pollutants in an effluent
Reduction of nitrogen- and carbon-based pollutants
Related Subjects
54 ENVIRONMENTAL SCIENCES
CARBONACEOUS MATERIALS
COMBUSTION PRODUCTS
NITROGEN OXIDES
AIR POLLUTION CONTROL
ENVIRONMENTAL IMPACTS
GASEOUS WASTES
CHALCOGENIDES
CONTROL
MATERIALS
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL
WASTES
010800* - Coal
Lignite
& Peat- Waste Management
010900 - Coal
Lignite
& Peat- Environmental Aspects
014000 - Coal
Lignite
& Peat- Combustion
540120 - Environment
Atmospheric- Chemicals Monitoring & Transport- (1990-)