Combustion, Burners, Igniters and overfire systems
Combustion Systems

Since 1971, B&W has sold low NOx combustion systems for more than 120,000 MW of generating capacity in both new and retrofit boiler applications. Our low NOx burner technology has been successfully applied to a broad range of B&W and non-B&W units with varying fuel characteristics and boiler arrangements. We also pioneered the development and application of NOx ports and air staging for reducing NOx emissions. Combined with our other technologies, such as burners and selective catalytic reduction systems, overfire air systems are part of an overall NOx reduction strategy. B&W also offers new and replacement FPS gas, oil and dual fuel igniters, igniter auxiliary equipment, optical and fiber optic flame scanners and control systems for wall-fired and corner-fired boiler applications.

Our combustion solutions include:

Combustion

Burners

AireJet® Low NOx Burner

AireJet Burners

B&W engineers designed the AireJet burner with an innovative burner structure — a burner built around a center jet of air, encircled by the fuel stream, and then wrapped in additional combustion air

  • Pulverized coal-fired boiler applications
  • Much cleaner burning so it requires less excess air to minimize carbon monoxide (CO) and unburned carbon
  • Higher boiler efficiency and improved plant heat rate
  • Excellent flame stability and turndown

AireJet Burner Mechanical Design Features

Use this quick guide to learn more about the vital parts of the AireJet Burner. Hover over the numbers.

 AireJet Burner


Sleeve Damper ActuatorCore Air Inlet Duct and DamperPitot GridOuter Spin VanesInner Spin VanesSliding LinkageSleeve DamperCore Camper ActuatorCeramic-Lined Nozzle and Core Components

Ceramic-Lined Core Elements and Coal Nozzle

Ceramic protection against erosion on core components
inside the coal nozzle and for the coal nozzle

Core Damper Rotary Actuator

Adjusts core air flow to minimize emissions, and for idle/cooling position

Fixed Spin Vanes in Inner Air Zone 

Provides proper swirl to secondary air through inner air zone for ignition

Fixed and Adjustable Vanes in Outer Zone

Fixed vanes improve peripheral air distribution;
adjustable vanes are tuned during commissioning to
minimize emissions

Pitot Grid

Provides a relative indication of secondary air flow to
the main burner assembly using a 30-point
impact/suction device to facilitate balancing air flow
during commissioning

Main Sleeve Damper

Regulates secondary air flow to inner and outer air zones
of the burner, independent of swirl

Sleeve Damper Linear Actuator

Adjusts secondary air flow to main burner assembly
for normal operation, light-off, or idle/cooling conditions

Sliding Linkage

Heavy-duty, non-binding, lever arm movement to adjust outer spin vanes

Core Air Damper

Controls secondary air flow to center core air zone of burner

DRB-4Z™ Low NOx Burner

DRB-4z Burner

The advanced DRB-4Z is designed to produce lower emissions by featuring a patented transition zone. This zone acts as a buffer between the fuel rich flame core and secondary combustion air streams.     

  • Pulverized coal-fired boiler applications
  • Superior mechanical reliability and operation
  • Rugged construction, integrated design
  • Complete shop assembly – ready for installation
  • New or retrofit applications

DRB-4Z Burner Mechanical Design Features

Use this quick guide to learn more about the vital parts of the DRB-4Z Burner. Hover over the numbers.

Low NOx Burner


Outer Spin VanePitot GridFixed VaneMain Sliding Air DamperTransition Zone Sliding Air DamperLinear ActuatorTransition ZoneInner Spine Vane

Fixed Spin Vanes for Outer Air Zone

Improves peripheral air distribution within the burner
and reduces pressure drop

Adjustable Spin Vanes for Inner Air Zone

Stabilizes ignition at the tip of the coal nozzle

Linear Actuator

Easily adjusts the main sliding air damper position for
light-off, full-load and idle/cooling

Main Sliding Air Damper

Controls secondary air flow rate to the inner and outer
air zones of the burner, independent of swirl

Adjustable Spin Vanes for Outer Air Zone

Provides proper mixing of the secondary air to the end
of the flame

Pitot Grid

Provides a relative indication of air flow with a 30 point
impact/suction device to balance air flow among burners
during commissioning

Sliding Linkage

Heavy-duty, non-binding, lever arm movement to control
inner and outer spin vane settings — position is optimized
and fixed during commissioning

Transition Zone

Enhances NOx reduction by providing limited recirculation
regions between primary and secondary air streams

Transition Zone Sliding Air Damper

Regulates air to transition zone to optimize emissions

Low NOx XCL-S® Burner

XCL-S Burner

This advanced low NOX burner was developed to achieve superior NOperformance in burner-only applications and in applications using overfire air (OFA) and/or flue gas recirculation (FGR).

  • Oil and gas boiler applications
  • Demonstrated NOx reductions in excess of 90 percent
  • Demonstrated low NOx emissions with and without the use of FGR
  • Superior flame stability and burner turndown
  • Lower CO emissions
  • Improved excess air control
  • On-line adjustability to optimize performance
  • Low-cost plug-in design
  • Proven mechanical reliability and operation
  • Complete shop assembly – ready for installation

XCL-S Burner Mechanical Design Features

Use this quick guide to learn more about the vital parts of the XCL-S Burner. Hover over the numbers.

XCL-S Burner


Linear ActuatorCore Air DamperSliding Air DamperAir Measurement GridExternally Adjustable Spin VanesAdjustable Hemispherical Gas SpudsBurner Support SystemI-Jet Oil Gun

Adjustable Hemispherical Gas Spuds

Can be rotated to optimize NOx reduction and are removable
while the boiler is in service

Air Measurement Grid

Ensures an accurate indication of relative air flow with a
multi-point impact/suction device

Burner Support System

Supports the burner and allows for differential expansion

Core Air Damper

Adjusts core air flow to the oil gun or gas spuds for
optimizing combustion

Externally Adjustable Spin Vanes

Provide proper mixing of the secondary air and fuel
(to the end of the flame) – vane position is optimized
and fixed during commissioning

I-Jet Oil Gun

Produces a finer oil spray, reduces particulate and opacity
emissions, minimizes atomizer plugging

Linear Actuator

Easily adjusts the main air sliding damper position for light-off,
full-load and out-of-service cooling

Sliding Air Damper

Adjusts the majority of secondary air flow to the outer air
zone, independent of swirl, to balance air flow among burners
during commissioning

DRB-XCL® Low NOx Burner

DRB-XCL

The DRB-XCL has proven to be the workhorse burner in achieving low NOx emissions requirements. This burner remains an integral part of achieving optimized NOx reduction solutions.   

  • Pulverized coal-fired boiler applications
  • Superior mechanical reliability and operation
  • Rugged construction, integrated design
  • Complete shop assembly — ready for installation
  • New or retrofit applications
  • Plug-in design

DRB-XCL Burner Mechanical Design Features

Use this quick guide to learn more about the vital parts of the DRB-XCL. Hover over the numbers.

DRBXCL Burner


Adjustable VanesBladed ImpellerOuter Zone Adjustable VaneFixed Spin VanesPitot GridSliding Air DamperLinear ActuatorSliding LinkageBurner Support System

Adjustable Spin Vanes for Inner Air Zone

 Stabilizes ignition at the tip of the coal nozzle

Blade Impeller

Beneficial for reducing unburned carbon loss while
still promoting low NOx emissions

Fixed Spin Vanes for Outer Air Zone

Improves peripheral air distribution within the burner
and reduces pressure drop

Linear Actuator

Easily adjusts the secondary air sliding damper position for
light-off, fullload and idle/cooling

Adjustable Spin Vanes for Outer Air Zone

Provides proper mixing of the secondary air to the end
of the flame

Pitot Grid

Provides a relative indication of air flow with a 30 point
impact/suction device to balance air flow among burners
during commissioning

Sliding Air Damper

Controls secondary air flow rate to the inner and outer
air zones of the burner, independent of swirl

Sliding Linkage

Heavy-duty, non-binding, lever arm movement to control
inner and outer spin vanes settings — position is
optimized and fixed during commissioning

Burner Support System

Allows for differential expansion

Flame Burner

Project / case feature item

Combustion Tuning Services using FlameDoctor

Sponsored by Electric Power Research Institute, Inc. (EPRI) and jointly developed by B&W and Oak Ridge National Laboratory, the Flame Doctor® burner diagnostic system is advanced technology that uses non-linear dynamics to analyze the combustion process with the signals from individual flame scanners.

Benefits of Tuning with Flame Doctor® Diagnostics

  • Pinpoints individual burner performance
  • Reduces emissions
  • Improves fuel utilization
  • Improves unit performance
  • Speeds tuning
  • Identifies possible burner mechanical issues    

Overfire Air Systems (Wall- and Corner-fired Boilers)

Wall-fired air ports

Overfire Air Port
B&W’s dual zone overfire air (OFA) port provides an online means to stage the introduction of air into the combustion process for more effective NOx control. A sliding sleeve damper allows the regulation of air to each port. Cutting the amount of air supplied to the burners causes a fuel rich/oxygen lean zone to develop; NOx is suppressed and reduced as it passes through the fuel rich zone. The overfire air system completes the combustion process.
 
Our dual zone ports simultaneously provide air across the furnace to mix with combustibles well away from the walls, while also supplying air to mix with combustibles in the proximity
of the ports. The heavy-duty design is well suited for extreme conditions of utility boilers. Online adjustability provides the means to fine tune mixing and minimize NOx emissions.

Corner-fired air ports

Corner-fired OFA Port

Overfire air has proven to very effective in corner-fired boilers originally designed by Combustion Engineering (CE)/Alstom, and is the dominant method of NOx control with modern systems. We developed our innovative overfire air system for corner-fired boilers using proprietary computational fluid dynamic (CFD) modeling and experience gained from full-scale commercial applications.

B&W’s staged combustion system for corner-fired boilers offers these benefits:

  • Proven NOx reduction
  • Proven design approach with unit-by-unit customization
  • Maintains boiler thermal performance
  • Design simplicity for ease of construction and maintenance
  • Minimal modifications to structural members, sootblower arrangement and platforms
  • Superior mechanical reliability and operation
  • Operational flexibility
  • Rugged design and fabrication for reduced maintenance