Oxidizing oxygen-fuel burner firing for reducing NOx emissions from high temperature furnaces
US5954498A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Feb 26, 1998 |
| Grant date | Sep 21, 1999 |
| Priority date | — |
| Expiry date | Feb 26, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P40/57
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
Burner firing method and device are presented where an oxidizing oxygen-fuel burner is fired at an angle to the reducing air-fuel burner flame to reduce overall NOx emissions from high temperature furnaces. The oxidizing oxy-fuel burner stoichiometric equivalence ratio (oxygen/fuel) is maintained in the range of about 1.5 to about 12.5. The reducing air-fuel burner is fired at an equivalence ratio of 0.6 to 1.00 to reduce the availability of oxygen in the flame and reducing NOx emissions. The oxidizing flame from the oxy-fuel burner is oriented such that the oxidizing flame gas stream intersects the reducing air-fuel flame gas stream at or near the tail section of the air-fuel flame. The inventive methods improve furnace temperature control and thermal efficiency by eliminating some nitrogen and provide an effective burnout of CO and other hydrocarbons using the higher mixing ability of the oxidizing flame combustion products. The simultaneous air-fuel and oxy-fuel burner firing can reduce NOx emissions anywhere from 30% to 70% depending on the air-fuel burner stoichiometric ratio.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.