CFD modeling has been used extensively in furnace combustion with an objective of Low-NOx Burner (LNB) and Over-Fire Air (OFA) design (either traditional OFA or advanced OFA) for a specific boiler with a specific fuel. It is routinely used in our feasibility study as well as detailed engineering phase. The model provides detailed predictions of furnace combustion, heat transfer, and emissions (incl. NOx, CO, LOI, etc). We have used CFD combustion model and designed over 50 OFA systems.
Our Approach to OFA Design:
- In conjunction with burner replacement or upgrades
- Conventional OFA and/or advanced boosted or hybrid OFA depending on NOx reduction requirement
- Customized design to fit specific furnace configurations
- CFD combustion modeling to locate the OFA nozzles
Models of a 600-MW wall-fired furnace combustion between baseline and Boosted OFA. The model demonstrates that while Boosted OFA reduces NOx, the furnace O2 distribution and CO combustion are improved by Boosted OFA high momentum air jets.