Low NOx Burners
Riley Power offers a complete portfolio of low NOx burners for any OEM’s wall-fired or corner-fired steam generator, for both new construction, as well as for existing units. We also provide unique burner system upgrades for the Riley TURBO® furnace designs. All RPI burners can be designed to operate with or without overfire air, as well as other low NOx technologies, such as SCR and SNCR. All units are designed to achieve the lowest emissions, highest reliability, and long life utilizing in-house CFD modeling, decades of experience on many different OEM’s equipment, and the latest materials available.
Riley Power’s CCV® (Controlled Combustion Venturi) low NOx burner is designed for any OEM’s new or existing wall-fired coal steam generator, as well as coal and oil combination fired applications. It has also been successfully installed in numerous cell burner installations as a retrofit burner, without modification to existing pressure parts. Over 2300 CCV® burners have already been installed on coal fired units.
Superior NOx control is achieved utilizing Riley Power Inc.’s patented venturi coal nozzle and low-swirl spreader located in the center of the CCV® burner. The venturi nozzle concentrates the fuel and air in the center of the coal nozzle creating a very fuel-rich mixture. Devolatilization of the coal in the fuel-rich mixture occurs at the burner exit in an oxygen-lean primary combustion zone, resulting in lower fuel NOx conversion.
Riley Power Inc.’s CCV® (Controlled Combustion Venturi ) Dual Air Zone Burner demonstrates 20% additional NOx Reduction beyond the original Single Register Burner. The CCV® Dual Air Zone low NOx burner utilizes the same low NOx venturi coal nozzle design used in the CCV® Single Register burner, which produces a fuel-rich flame core, but also incorporates a dual air zone arrangement.
Utilizing its extensive experience in designing firing systems for almost 100 years, as well as current software technology, Riley Power can provide combustion solutions for utility and industrial boilers with corner/tangential firing systems. Extensive application of modern design tools, including our in-house CFD modeling capabilities; helps insure optimal performance and technical compliance for each specific application. And using special materials, such as cladding and abrasion resistant coatings, helps enhance system reliability.
Coal (TURBO® Furnace)
Riley Power Inc. continues to improve the design of its low NOx Directional Flame (DF) Burners used in coal fired TURBO® Furnaces. The latest improvement incorporates a patented tilting coal nozzle. The new design allows for on-line adjustment of the nozzle tip to alter the direction of the coal entry into the furnace. The tilting coal nozzle design is capable of up and down movement typically + / – 20° from the normal burner axis. The result is better control of steam temperature, flame attachment, NOx emissions, and furnace slagging.
The tip is constructed of high-grade alloy materials to extend wear life and mechanical reliability. Adjacent sets of coal nozzle tips are manually operated in unison by an actuator on the burner front .
DF Burner Upgrade Features and Benefits
- Tilting Coal Nozzle Tip
- Improved flame attachment
- Lower NOx emissions with minimal change in UBC and CO
- Better steam temperature control
- Reduced furnace slagging
- Partitioned windbox for better air control
- Improved staged combustion
- Separate control of OFA and burner air flow
The system includes the DF burner with internal windbox partitioning, tilting coal nozzles, and overfire air (OFA), all optimized through the use of in-house CFD modeling. The special windbox partitioning enables the OFA to be controlled independently from the main combustion air feeding the burners.
Oil & Gas (Wall-fired)
Riley Power’s (RPI) advanced STS® (Swirl Tertiary Staged) Burner design was developed utilizing proven European technology, but incorporating Riley Power’s air register design, which has been used successfully on RPI’s coal-fired low-NOx CCV® burners. STS® Burners have been successfully retrofitted on gas and oil-fired boilers in Europe and the United States. The goals for low emission requirements were achieved with the use of this burner alone or in combination with overfire air (OFA), and flue gas recirculation (FGR).
- Burner Capacity 40 to 250 MMBtu/hr
- NOx reductions up to 90% on gas and 75% on oil with OFA and FGR
- Independent flow and swirl control
- Low CO emissions
- Low burner air pressure drop – typically less than 5″ H2O
- Burner to burner air flow biasing capability to correct unbalanced windboxes
- High mechanical reliability from proven register design
- Can be retrofitted to most wall-fired applications without modification of burner throat tube opening
- Can be adapted to fit many existing windbox openings
- Externally adjustable gas canes to eliminate combustion induced vibration
- Flame shaping capability
- Low excess air operation
Improved Air Flow Measurement
Improved burner optimization, real-time continuous air flow balancing capability, and control of individual burner stoichiometry are now available for existing Riley CCV® SRB and CCV® DAZ burners in your plant. Individual Burner Air Measurement (IBAM™) Probes, available from Riley Power Inc., accurately measure individual burner air flow in a multiple burner windbox arrangement. Furthermore, in CCV® DAZ applications, the IBAM™ probes provide the ability to adjust the air flow split between the secondary and tertiary air zones, a critical control to minimize NOx emissions. This air flow measurement device is standard on all new Riley Power Inc. Low-NOx Coal, Oil, and Gas burner applications. Results of extensive calibration testing in Air Monitor Corporation’s wind tunnel facility have yielded measurement accuracies to within 3.5%. Accurate burner air flow measurements make it possible to correct burner-to-burner secondary air flow imbalances caused by the furnace windbox design, improving the control of NOx and CO emissions and flyash UBC in low-NOx systems.
Air Monitor IBAM™ probes:
- Improve control of individual burner stoichiometry and air to fuel ratio
- Improves control of secondary air / tertiary air flow spit and NOx emissions
- Balance burner-to-burner secondary air flow, or deliberately bias air flow if desired
- Increase burner turndown capability
- Reduce NOx through lower excess air operation
- Reduce LOI
- Reduce lower furnace corrosion potential
- Reduce burner throat slagging
- Individual Burner Air Flow Measurement and CFD Modeling Expedites Low Nox Burner optimization and Boiler Commissioning
Riley Power Inc. installs the IBAM™ probes upstream of the secondary air (SA) and tertiary air (TA) swirl vanes to avoid high swirling flow impact on the air flow measurement accuracy. The IBAM™ probes operate on a self-averaging, multi-point pitot probe principle to measure the total and static pressure components of air flow. Furthermore, the design of the probes minimizes air direction effects because of strategically located static pressure sensing ports.
As an option, the IBAM™ probes pressure reading can be transmitted to the control room as mass flow or velocity measurements within the secondary air and tertiary air barrels. This real time feedback provides the ability to fine tune the air flow control and can be used in conjunction with other combustion optimization tools to enhance boiler performance.