Opti-Flow™ Coal Burners for Wall-Fired Boilers
General Information
- Description
- Details
- Advantages
- Overfire Air
- Flames
- Fuels
- Emissions
Siemens uses a systems approach to develop their products. All factors affecting the thermal and emissions performance of the boiler are considered during the design process. As a result of this thorough analysis, all of the products Siemens supplies to resolve your combustion problems will function together effectively and reliably.
For wall-fired boilers, Siemens can:
- Completely replace the existing burners (Fuel Injector and Register)
- In some cases, replace the fuel injector only
- Provide burners for new boilers
Advantages of the Siemens low NOx burner:
- The burner is the primary NOx control element and it produces a stable, highly effective low NOx flame
- The flame is stable inside the burner throat, regardless of fuel type
- The Opti-Flow™ burner has a successful history of substantially reducing furnace slag formation
- This burner minimizes NOx without compromising boiler performance
When maximum NOx reduction is desired, Overfire Air (OFA) will be part of the solution:
- OFA is used as a secondary NOx control element while maintaining burner stoichiometry (S) > 1
- Burners can operate sub-stoichiometrically, S < 1, in conjunction with OFA, to further reduce NOx where furnace and fuel permit
More on OFA
An Opti-Flow™ Low NOx Burner produces a unique flame:
The photographs above show flames in a 700 MW boiler with 56 burners firing lignite. Flames are rooted in throat and stable, with low emissions. Left and right photos show flames with OFA closed and open, respectively.
Opti-Flow™ Low NOx Burners Handle Diverse Fuels
Opti-Flow™ Low NOx Burner U.S. Coal Experience
- Lignite
- Powder River Basin (PRB)
- Bituminous
- Eastern and Western low sulfur
- Eastern high sulfur - Petroleum coke (Petcoke)
- Only burner manufacturer to burn 100% Petcoke in low NOx burners
Foreign Coal Experience
Siemens is the first low NOx burner supplier to receive contracts for burner retrofits in
China and Australia, burning:
- Chinese bituminous coal
- Australian coal
Retrofitted Opti-Flow™ Low NOx Burners Yield Significant NOx Reductions
NOx and LOI/UBC levels attained with Opti-Flow™ burners:
Bituminous Coal
- NOx levels below 0.3 lb/MBtu are attained when overfire air is used in conjunction with the Opti-Flow™ burner
- LOI/UBC remains in the same range as before.
Lignite and PRB
- NOx levels in the “mid teens” with lignite and PRB when overfire air is used in conjunction with the Opti-Flow™ burner.
Our Portfolio (2)
Opti-Flow™ Fuel Injectors for Low NOx Applications
- Description
- Universal fuel injector
- Flow correcting device
- Equipment for scroll inlets
Opti-Flow™ low NOx segmented nozzle tip with external stabilizers
The key to our successful fuel injector (FI) lies in the engineering and design of the lobed FI tip. This tip promotes an internally staged flame, which yields significant NOx emission reductions.
Inlet elbow with flow correcting device
- Flow correcting device on flatback is lined with erosion resistant materials and optimizes fuel distribution at nozzle
- Flatbacks can be installed into existing 90° elbows, or supplied as part of new elbows, if desired
- Flatback is easily removed for inspection or refurbishment, if required.
Equipment available for burners with scroll inlets
- Siemens has retrofit burners equipped with OEM scroll inlets by inserting fuel distribution enhancements into the existing scroll and replacing all other fuel injector components
- Recently, Siemens has been converting scroll inlet burners to an elbow inlet design by replacing the inlet scroll and the fuel injector
- Such changes can yield improved performance and lower maintenance.