Method and system for the disposal of coal preparation plant waste coal through slurry co-firing in cyclone-fired boilers to effect a reduction in nitrogen oxide emissions
US5988081A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jul 22, 1997 |
| Grant date | Nov 23, 1999 |
| Priority date | — |
| Expiry date | Jul 22, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF23C2201/301
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A method and system for the use of waste coal fines to reduce nitrogen oxides emissions from a coal-fired cyclone boiler. A coal water slurry including waste coal fines is injected as a co-firing fuel into a cyclone barrel of the cyclone boiler to partially oxidize the coal water slurry in a central portion of the cyclone barrel where injected. This produces a reducing zone having reducing gas species that convert nitrogen oxides to diatomic nitrogen. The coal water slurry can alternatively be injected into the cyclone barrel from a secondary combustion air conduit. The evaporation of the water from the coal water slurry reduces the overall combustion temperature in the cyclone barrel, further reducing the production of nitrogen oxides.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.