Abstract: A dual phase fuel feeder is disclosed that can be used to provide both solid fuels and liquid fuels to a boiler, such as a fluidized bed boiler. The fuel feeder includes a sloped chute which defines a solid feedpath. Gas distribution nozzles are located at the base of the fuel feeder, and secondary nozzles are located so as to be able to distribute a liquid or particulate fuel into the solid feedpath. This permits the liquid fuel to contact the solid fuel and be carried into the fluidized bed instead of becoming suspended above the bed.

Abstract: The present disclosure relates to a center air jet burner for burning low quality fuel including an annular pipe having a fuel inlet and a fuel outlet. A core pipe that includes a first opening and an opposite second opening that defines an inner zone, the core pipe extends within the annular pipe defining a first annular zone. A burner elbow is configured to supply a fuel airflow mixture including pulverized coal and primary air to the fuel inlet and the first opening. The first opening of the core pipe is eccentrically aligned relative to the fuel inlet of the annular pipe such that the fuel airflow mixture passing through the burner elbow is divided into an outer fuel rich stream having an increased amount of pulverized coal within the first annular zone and an inner fuel-lean stream having an increased amount of primary air within the inner zone.

Abstract: A coal nozzle assembly for a pulverized coal burner includes a diffuser. A flow conditioner also may be used with the assembly. The assembly conditions the coal/air flow before the coal/air flow is introduced to the furnace. The flow conditioner directs the coal into the diffuser where it is swirled to form a fuel rich outer ring disposed about an air rich inner portion before the fuel is delivered to the coal nozzle.

Abstract: The present disclosure relates to a center air jet burner for burning low quality fuel including an annular pipe having a fuel inlet and a fuel outlet. A core pipe that includes a first opening and an opposite second opening that defines an inner zone, the core pipe extends within the annular pipe defining a first annular zone. A burner elbow is configured to supply a fuel airflow mixture including pulverized coal and primary air to the fuel inlet and the first opening. The first opening of the core pipe is eccentrically aligned relative to the fuel inlet of the annular pipe such that the fuel airflow mixture passing through the burner elbow is divided into an outer fuel rich stream having an increased amount of pulverized coal within the first annular zone and an inner fuel-lean stream having an increased amount of primary air within the inner zone.

Abstract: A dual phase fuel feeder is disclosed that can be used to provide both solid fuels and liquid fuels to a boiler, such as a fluidized bed boiler. The fuel feeder includes a sloped chute which defines a solid feedpath. Gas distribution nozzles are located at the base of the fuel feeder, and secondary nozzles are located so as to be able to distribute a liquid or particulate fuel into the solid feedpath. This permits the liquid fuel to contact the solid fuel and be carried into the fluidized bed instead of becoming suspended above the bed.

Abstract: 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.

Abstract: A combustion apparatus capable of firing biomass fuel including a burner assembly which includes a biomass nozzle concentrically surrounded by a core air zone and extending axially along the length of the core air zone, the burner assembly residing within a windbox, the windbox being attached to a furnace of a boiler, and the burner assembly being connected to the furnace by a burner throat, through which air and fuel supplied to the burner assembly are emitted into the furnace.

Abstract: A coal nozzle assembly for a pulverized coal burner includes a diffuser. A flow conditioner also may be used with the assembly. The assembly conditions the coal/air flow before the coal/air flow is introduced to the furnace. The flow conditioner directs the coal into the diffuser where it is swirled to form a fuel rich outer ring disposed about an air rich inner portion before the fuel is delivered to the coal nozzle.

Abstract: An over fire air (OFA) port arrangement for a pulverized coal-fired boiler or furnace has at least one OFA port through each of the sidewalls for injecting OFA to increase residence time for each burner level. Plural OFA ports may be employed, staggered both vertically and horizontally to effectively deliver over fire air to the burner flames at the appropriate time and location to most efficiently reduce the formation of fuel NOx. OFA port configurations for both single-wall and opposed-wall fired furnaces and boilers are provided.

Abstract: A new burner apparatus and method of combusting fossils fuels for commercial and industrial application is provided wherein the new burner apparatus achieves low NOx emissions 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A coal burner with impeller for a furnace has a housing containing a plurality of sets of blades which direct the fuel from the coal nozzle into a plurality of non-intersecting flows directed obliquely towards the longitudinal axis of the housing. The non-intersecting flows create a fuel-rich devolatilization zone and an air-rich char burnout zone within the furnace and limit the flame length of the burner.

Abstract: A burner and port combination for the combustion of a pulverized coal fuel plus air mixture comprises a throat and a burner nozzle positioned at a central area of the throat. The burner nozzle has an inlet for receiving the pulverized coal fuel plus air mixture and an outlet for discharging the pulverized coal fuel plus air mixture. A secondary air tube is positioned laterally adjacent the burner nozzle at each lateral side of the nozzle in the throat for providing a first portion of a secondary air to the throat. A plurality of vanes are positioned at an upper portion of the throat above the burner nozzle and the tubes and at a lower portion of the throat below the burner nozzle tubes for deflecting a second portion of the secondary air from the burner nozzle.

Abstract: A low NO.sub.x burner system for a furnace having spaced apart front and rear walls, comprises a double row of cell burners on each of the front and rear walls. Each cell burner is either of the inverted type with a secondary air nozzle spaced vertically below a coal nozzle, or the non-inverted type where the coal nozzle is below the secondary air port. The inverted and non-inverted cells alternate or are provided in other specified patterns at least in the lower row of cells. A small percentage of the total air can be also provided through the hopper or hopper throat forming the bottom of the furnace, or through the boiler hopper side walls. A shallow angle impeller design also advances the purpose of the invention which is to reduce CO and H.sub.2 S admissions while maintaining low NO.sub.x generation.

Abstract: A burner for the combustion of a fuel plus air mixture comprises a central nozzle pipe having an inner surface with a portion which diverges outwardly. An axially moveable plug is positioned within the nozzle pipe and includes an outer wall with a diverging section extending within the diverging section of the nozzle pipe. By axially moving the plug, the cross sectional area of the space between the diverging surfaces increases and decreases for respectively decreasing and increasing the velocity of the fuel plus air mixture passing through the nozzle space. This reduces the formation of NO.sub.x and the length of the flame produced by the burner.