Flue gas recirculation method and system for combustion systems
US9033704B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 2010 |
| Grant date | May 19, 2015 |
| Priority date | — |
| Expiry date | Dec 19, 2031 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF26B2200/08
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method and system for improving high excess air combustion system efficiency, including induration furnaces, using a re-routing of flue gas within the system by gas recirculation. Flue gas is drawn from hot system zones including zones near the stack, for re-introduction into the process whereby the heat recovery partially replaces fuel input. At least one pre-combustion drying zone, at least one combustion zone, and at least a first cooling zone exist in these furnaces. At least one exhaust gas outlet is provided to each pre-combustion drying and combustion zone. At least part of the gaseous flow from each system zone exhaust outlet is selectively delivered to an overall system exhaust, the remaining flow being selectively delivered via recirculation to cooling zones. Recirculation flow is adjusted to meet required system temperatures and pressures. The method and system provide efficiency improvements, reducing fuel requirements and greenhouse gas emissions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.