Low NO.sub.x short flame burner with control of primary air/fuel ratio for NO.sub.x reduction
US5697306A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 1997 |
| Grant date | Dec 16, 1997 |
| Priority date | — |
| Expiry date | Jan 28, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF23D2201/20
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A burner for the combustion of a pulverized coal plus primary air mixture includes a nozzle pipe having an inlet for receiving a pulverized coal plus primary air mixture and an outlet for discharging same. A hollow plug extends axially within the nozzle pipe and defines an annular space between the plug and the nozzle pipe for conveying the pulverized coal plus primary air mixture therethrough. The hollow plug is axially moveable within the nozzle pipe. A variable amount of core air is supplied into the hollow plug so that it mixes with the primary air plus pulverized coal mixture at an outlet of the burner to vary the PA/PC ratio and maintain a desired primary air to primary coal ratio at the outlet of the burner. Natural gas can also be supplied into the hollow plug as a supplemental fuel for cofiring at the outlet end of the burner. The amount of core air supplied is based upon (1) the coal flow rate being provided to the burner, in lb/hr, and (2) the percent volatile matter content (%VM) in the coal being burned.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.