The Babcock & Wilcox Company

Other

Babcock & Wilcox Power Generation Group, Inc.

Mcdermott Technology, Inc.

Hamid Sarv

Albert D LaRue

Jeffrey A LaRose

Peter W Waanders

Daniel R Rowley

William J Kahle

Alan N Sayre

Ronald C Lenzer

John V Koslosy

Larry W Rodgers

Jennifer L Sivy

Keith C Kaufman

Albert D Larue

A large diameter mid-zone air separation cone is provided for decreasing NOx during burner operation by expanding the internal recirculation zone (IRZ) at the burner exit. The mid-zone air separation cone has a short cylindrical leading edge that fits in the outer air zone of a burner. The mid-zone air separation cone splits the outer air zone secondary air flow into two equal or unequal streams depending on the position of the air separation cone with respect to the outer air zone, and deflects a portion of the secondary air flow radially outward. Since the radial position of the air separation cone is farther from the burner centerline, the IRZ size is expanded and NOx emissions are minimized.

Large diameter mid-zone air separation cone for expanding IRZ

A method is disclosed for reducing the NOemission of fossil fuel burners. The method creates fuel-rich and fuel-lean zones within the boiler to enhance the removal of NOspecies by creating a plurality of NOreducing precursors.

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A new burner apparatus and method of combusting fossils fuels for commercial and industrial application is provided wherein the new burner apparatus achieves low NOemissions by supplying oxygen to the center of the burner flame in as manners so as to create a fuel rich internal combustion zone within the burner flame.

Burner with center air jet

An air swirler capable of liquid fuel atomization for a fuel fired burner in a furnace or boiler having a hollow guide pipe supporting several swirl blades at an end adjacent to the furnace. Openings connected by tunnels to the inside of the guide pipe are provided in the trailing edges of each swirl blade. A fuel pipe is concentric with the guide pipe forming an annular space therebetween. Gaseous substances such as oxygen or natural gas are provided through the annular space and liquid fuel is provided through the fuel pipe. The fuel and gaseous substances travel through the tunnels to the openings for liquid fuel atomization and pre-mixing at the burner throat to reduce NOformation.

Tunneled multi-swirler for liquid fuel atomization

A dual fuel burner including an elongated supply pipe and a gas injector for a boiler furnace having a plurality of peripheral openings around a center opening. The peripheral openings are pitched radially away from the longitudinal axis of the gas injector and also pitched either clockwise or counter-clockwise, to impart a swirling motion to gaseous fuel exiting the injector through the openings. A first sleeve member is concentrically spaced about the supply pipe and the gas injector to form an inner annular passageway for conveying a mixture of primary air and pulverized coal to the furnace combustion zone. A second sleeve member is concentrically spaced about the first sleeve member to form an outer annular passageway for conveying secondary air to the furnace combustion zone, and a plurality of circumferentially spaced vanes mounted within the outer annular passageway for inducing a swirling motion to the secondary air discharging from the outer annular passageway into the furnace combustion zone.

Dual fuel burner for a shortened flame and reduced pollutant emissions

A compound spin vane (CSV) for use in an air passage of a fossil fuel-fired burner. In one embodiment, the CSV is a multi-piece construction of platelike outer and inner vane elements connected to an intermediate platelike rail element. In another embodiment, the CSV includes at least two and possibly three vane portions, rigidly interconnected in spaced lateral relationship with respect to each other. If desired, the vane portions may be simple, curved planar surfaces, and may be arranged with trailing edges arranged at angles with respect to each other. The invention may be employed as a replacement for flat spin vanes found in secondary air passages of known single and dual register burners. When used in such manner in a single register burner, the invention changes secondary air flow characteristics so as to mimic those commonly found in a dual register burner.

Compound burner vane

A burner having lower emissions and lower unburned fuel losses by implementing a transition zone in a low NO.sub.x burner. The improved burner includes a pulverized fuel transport nozzle surrounded by the transition zone which shields the central oxygen-lean fuel devolatilization zone from the swirling secondary combustion air. The transition zone acts as a buffer between the primary and the secondary air streams to improve the control of near-burner mixing and flame stability by providing limited recirculation regions between primary and secondary air streams. These limited recirculation regions transport evolved NO.sub.x back towards the oxygen-lean fuel pyrolysis zone for reduction to molecular nitrogen. Alternate embodiments include natural gas and fuel oil firing.

Pulverized coal burner

An air premixed natural gas burner having reduced thermal and prompt NO.sub.x emissions employs a central, cylindrical core chamber and an outer annular chamber separated by a hollow barrel having a plurality of gas spuds at a front end of the burner adjacent to a burner throat. The plurality of gas spuds introduces natural gas into a core chamber air flow passing through a fixed swirler and controlled by a sliding air flow damper associated with the central, cylindrical core chamber. A reduced air/fuel stoichiometric ratio (of approximately 0.6) is preferably maintained at an outlet of the central, cylindrical core chamber. The balance of the combustion air is provided through the outer annular chamber to maintain an overall or cumulative burner stoichiometric ratio of approximately 1.05.

Air premixed natural gas burner

A burner for the combustion of a pulverized coal plus primary air mixture includes a nozzle pipe having an inlet for receiving a pulverized coal plus primary air mixture and an outlet for discharging same. A hollow plug extends axially within the nozzle pipe and defines an annular space between the plug and the nozzle pipe for conveying the pulverized coal plus primary air mixture therethrough. The hollow plug is axially moveable within the nozzle pipe. A variable amount of core air is supplied into the hollow plug so that it mixes with the primary air plus pulverized coal mixture at an outlet of the burner to vary the PA/PC ratio and maintain a desired primary air to primary coal ratio at the outlet of the burner. Natural gas can also be supplied into the hollow plug as a supplemental fuel for cofiring at the outlet end of the burner. The amount of core air supplied is based upon (1) the coal flow rate being provided to the burner, in lb/hr, and (2) the percent volatile matter content (%VM) in the coal being burned.

Low NO.sub.x short flame burner with control of primary air/fuel ratio

A method for reducing NO.sub.x produced by the burning of fuels includes providing a hydrocarbon and nitrogen mixture to a plasma arc generator for producing NO.sub.x reducing precursors which are, in turn, provided near the burning of the fuel for reacting and reducing NO.sub.x emissions. These precursors include N, H, HCN, CH.sub.i and NH.sub.i, etc.

Growing community of inventors

Canton, OH, United States of America

Hamid Sarv