Flue gas recirculation method and system for combustion systems
US9448009B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 2015 |
| Grant date | Sep 20, 2016 |
| Priority date | — |
| Expiry date | May 19, 2035 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E20/30
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
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.