Abstract:
Horizontally arranged burners for boiler furnaces are provided where each burner includes a fuel nozzle surrounded by a secondary air outlet. The fuel nozzle and secondary air outlets may tilt in tandem with respect to an air plenum supplying inner secondary air and a fuel carrier providing fuel. Also provided are outer secondary air buckets that may independently tilt with respect to a frame connected to the air plenum. This arrangement can be installed as a retrofit in a conventional horizontal furnace system or in a newly built system. The fuel nozzle and secondary air outlet, and secondary air buckets may all tilt in unison or may all tilt independently. The tilting assists with optimizing a flame temperature profile within the furnace.
Abstract:
An improved end housing for nozzle assemblies used to project a stream of particulate coal into a burner housing. The improvement includes the addition of vertically-oriented, spaced parallel aiming plates. A four nozzle burner assembly has two sets of diagonally opposite nozzles in which all nozzles are aimed directly at the fireball center.
Abstract:
An improved end housing for nozzle assemblies used to project a stream of particulate coal into a burner housings The improvement includes the addition of vertically-oriented, spaced parallel aiming plates. A four nozzle burner assembly has two sets of diagonally opposite nozzles in which all nozzles are aimed directly at the fireball center.
Abstract:
A solid fuel nozzle tip (201) having at least first (205) and second (207) ceramic shells is provided by the present invention. An inlet end of the first ceramic shell (205) is interconnected to a pulverized solid fuel nozzle (34), and an outlet end (301) of the first ceramic shell (205) is interconnected to an inlet end (305) of the second ceramic shell (207).
Abstract:
A coal nozzle apparatus which includes a generally cylindrical main body and a generally cylindrical tip section disposed in generally coaxial relationship with the main body. The apparatus includes apparatus for mounting the tip section in relation to the body section, including two coaxial pins which, each have an axial portion cooperating with the main body and another axial portion connected to the tip section; each of the pins has a head, each of which is disposed proximate to the geometric center line of the body portion. Each of the pins has an axis that is generally coincident with a diameter of the main body. In some forms, the head of each pin is generally cylindrical in shape and the apparatus for mounting includes respective counterbores dimensioned and configured for cooperation therewith. The apparatus for pivoting may include a generally cylindrical nozzle front that is fixed to the main body and has an inner face, with the tip section disposed in side abutting relation to the nozzle front. The counterbores may be disposed in the nozzle front and the heads may be disposed in substantially flush relationship to the inner face of the nozzle front, and the pins may be welded to the nozzle front.
Abstract:
A flame retaining nozzle tip for a burner for a pulverized fuel fired furnace receiving a primary stream of pulverized fuel and primary transport and combustion air for discharge into the combustion zone of the furnace comprises a hollow, open-ended, choke or body having an inlet end of generally polygonal flow cross-section for receiving the stream and an outlet end of generally rounded cross-section for accelerating and discharging the stream into the furnace. The outlet end of the choke has a flow cross-sectional area that is less than that of the inlet end to provide choking action. An elongated center element is mounted in coaxial alignment with a central axis of the choke body extending between the inlet and outlet ends. A plurality of swirl vanes are mounted around the central axis and are angularly disposed relative to the general flow direction with inner edges of the vanes spaced equilaterally around and connected to the central element and outer edges connected to the inside surfaces of the choke body. The vanes cause the stream of primary air and pulverized fuel to rotate rapidly around the central axis as the stream passes through the outlet end.
Abstract:
An integrated low NO.sub.x tangential firing system (12) that is particularly suited for use with pulverized solid fuel-fired furnaces (10), and a method of operating a pulverized solid fuel-fired furnace (10) equipped with an integrated low NO.sub.x tangential firing system (12). The integrated low NO.sub.x tangential firing system (12) when so employed with a pulverized solid fuel-fired furnace (10) is capable of limiting NO.sub.x emissions therefrom to less than 0.15 lb./10.sup. 6 BTU, while yet maintaining carbon-in-flyash to less than 5% and CO emissions to less than 50 ppm. The integrated low NO.sub.x tangential firing system (12) includes pulverized solid fuel supply means (62), flame attachment pulverized solid fuel nozzle tips (60), concentric firing nozzles, close-coupled overfire air (98,100), and multi-staged separate overfire air (104,106).
Abstract:
A low-nox burner for use in industrial furnaces and/or boilers which burn pulverized coal. The burner includes a burner tip which divides an annular pulverized coal stream into alternating fuel-rich and fuel-lean streams. The tip includes a plurality of alternating main and secondary blade members which are skewed to produce rotational movement in the streams. The main blade has a leading edge that is aligned with a radial vector extending through a center axis of the burner and a trailing edge that is tilted with respect to the radial vector in order to define a substantially planar surface between the leading and trailing edges. The secondary blade includes leading and trailing edges that are both aligned with radial vectors and defines a twisted surfaces between the edges. The secondary blade is skewed with respect to the longitudinal direction by an angle that is substantially greater than the angle at which the main blade is skewed. As a result, channels having converging cross sections are defined between the main blade and one adjacent secondary blade, and diverging channels are defined by the main blade and another adjacent secondary blade. During operation, the tip creates a fuel-rich zone surrounded by a fuel-lean zone in the combustion region.
Abstract:
A solid fuel nozzle tip for issuing a flow of mixed solid fuel and air into a boiler or furnace includes an outer nozzle body having an outer flow channel extending therethrough from an inlet to an outlet of the outer nozzle body. An inner nozzle body has an inner flow channel extending therethrough from an inlet to an outlet of the inner nozzle body. The inner nozzle body is mounted within the outer nozzle body with the inner flow channel inboard of and substantially aligned with the outer flow channel. The inner and outer nozzle bodies are joined together so as to accommodate movement relative to one another due to thermal expansion and contraction of the outer and inner nozzle bodies.
Abstract:
A solid fuel nozzle tip for issuing a flow of mixed solid fuel and air into a boiler or furnace includes an outer nozzle body having an outer flow channel extending therethrough from an inlet to an outlet of the outer nozzle body. An inner nozzle body has an inner flow channel extending therethrough from an inlet to an outlet of the inner nozzle body. The inner nozzle body is mounted within the outer nozzle body with the inner flow channel inboard of and substantially aligned with the outer flow channel. The inner and outer nozzle bodies are joined together so as to accommodate movement relative to one another due to thermal expansion and contraction of the outer and inner nozzle bodies.