Patent Publication Number: US-7216594-B2

Title: Multiple segment ceramic fuel nozzle tip

Description:
FIELD OF THE INVENTION 
   This invention is related to firing systems for use with pulverized solid fuel-fired furnaces, and more specifically, to a multiple segment pulverized solid fuel nozzle tip with a ceramic component for use in such firing systems. 
   BACKGROUND OF THE INVENTION 
   It has long been known in the art to employ pulverized solid fuel nozzle tips in firing systems of the type that are utilized in pulverized solid fuel-fired furnaces. A typical pulverized solid fuel nozzle tip comprises inner and outer shells disposed coaxially in spaced relationship to define a first flow passageway within the inner shell through which a pulverized fuel and air mixture passes into a furnace, and a second flow passageway between the inner shell and the outer shell through which air passes into the furnace. Typically, one or more splitter plates are disposed within the inner shell parallel to the axis of the nozzle tip to divide the flow passageway within the inner shell into multiple subpassages. Oftentimes nozzle tips are configured so as to be tiltable upward or downward in order to direct the fuel-air mixture discharging into the furnace. 
   Examples of pulverized solid fuel nozzle tips can be found in U.S. Pat. No. 2,895,435 entitled “Tilting Nozzle For Fuel Burner”, which issued on Jul. 21, 1959 and which is assigned to the same assignee as the present patent application; U.S. Pat. No. 4,274,343 entitled “Low Load Coal Nozzle”, which issued on Jun. 23, 1981 and which is assigned to the same assignee as the present patent application; U.S. Pat. No. 4,356,975 entitled “Nozzle Tip For Pulverized Coal Burner”, which issued on Nov. 2, 1982 and which is assigned to the same assignee as the present patent application; U.S. Pat. No. 4,434,727 entitled “Method For Low Load Operation Of A Coal-Fired Furnace”, which issued on Mar. 6, 1984 and which is assigned to the same assignee as the present patent application; U.S. Pat. No. 4,520,739 entitled “Nozzle Tip For Pulverized Coal Burner”, which issued on Jun. 4, 1985 and which is assigned to the same assignee as the present patent application; U.S. Pat. No. 4,634,054 entitled “Split Nozzle Tip For Pulverized Coal Burner”, which issued on Jan. 6, 1987 and which is assigned to the same assignee as the present patent application; U.S. Pat. No. 5,315,939 entitled “Integrated Low NO x  Tangential Firing System”, which issued on May 31, 1994 and which is assigned to the same assignee as the present patent application; and U.S. Pat. No. 6,089,171 entitled “Minimum Recirculation Flame Control (MRFC) Pulverized Solid Fuel Nozzle Tip”, which issued on Jul. 18, 2000 and which is assigned to the same assignee as the present patent application. 
   A common material composition for pulverized solid fuel nozzle tips is stainless steel. Typically, a stainless steel used in such a nozzle tip is one with a relatively high temperature rating. While stainless steel has several desirable material properties, including ease of effort in incorporating it into the finished product, toughness, durability, high temperature strength, and ductility, certain material properties of conventional pulverized solid fuel nozzle tips comprised of stainless steel often force operators of pulverized solid fuel combustion facilities to operate their facilities in a less than optimal economic manner to avoid exceeding the physical limits of conventional pulverized solid fuel nozzle tips. 
   Two such limiting material properties are the ability of a stainless steel pulverized solid fuel nozzle tip to maintain its structural integrity at a high temperature (i.e., the maximum operating temperature) and the wear resistance of the pulverized solid fuel nozzle tip. A common maximum operating temperature for a stainless steel pulverized solid fuel nozzle tip is about 2100 degrees Fahrenheit (2100° F.), though it is not uncommon that the actual operating temperature of the pulverized solid fuel combustion facility can reach or exceed 2500 degrees Fahrenheit (2500° F.). Although there exist design and operating approaches which are configured to prevent exposure of the pulverized solid fuel nozzle tip to the actual pulverized solid fuel combustion facility operating temperature such as, for example, providing cooling air within or around the pulverized solid fuel nozzle tip, there is still some risk that the pulverized solid fuel nozzle tip may nonetheless be exposed to temperatures above the recommended maximum operating temperature in spite of the use of such design and operating approaches. For example, in the event that cooling air, which would normally protect a pulverized solid fuel nozzle tip, is, in fact, not supplied, or is only inadequately supplied, the pulverized solid fuel nozzle tip may be exposed to temperatures greater than its recommended maximum operating temperature. Excess exposure to temperatures beyond a recommended maximum operating temperature may cause a stainless steel pulverized solid fuel nozzle tip to fail during operation, causing negative economic impact. 
   The relatively modest wear resistance properties of the stainless steel in a stainless steel pulverized solid fuel nozzle tip may so compromise the pulverized solid fuel nozzle tip that the pulverized solid fuel nozzle tip fails between regularly scheduled maintenance outages, thus leading to the necessity of replacing the pulverized solid fuel nozzle tip at an unscheduled, economically disadvantageous time. While the wear resistance of a stainless steel pulverized solid fuel nozzle tip may be enhanced by measures such as, for example, coating the leading edges of the splitter plates of the pulverized solid fuel nozzle tip with a wear resistant material, such measures add to the manufacturing complexity and the weight of the thus treated pulverized solid fuel nozzle tip, thus detrimentally adding to the costs of the pulverized solid fuel nozzle tip. 
   In addition to those typical characteristics of a stainless steel pulverized solid fuel nozzle tip which may lead to unplanned operational failure, there are other characteristics of a stainless steel pulverized solid fuel nozzle tip which detract from the desirability of such pulverized solid fuel nozzle tips. For example, depending upon the pulverized solid fuel combustion facility and the type of pulverized solid fuel being combusted, a stainless steel pulverized solid fuel nozzle tip may experience slag build up attributable, in part, to the tendency of slag to bond to the surface of stainless steels. If the slag build up continues, the pulverized solid fuel nozzle tip may ultimately be completely blocked to through flow of the pulverized solid fuel. 
   One solution to the deficiencies of stainless steel pulverized solid fuel nozzle tips discussed above is found in U.S. Pat. No. 6,439,136 entitled “Pulverized Solid Fuel Nozzle Tip With Ceramic Component”, which issued on Aug. 27, 2002 and which is assigned to the same assignee as the present patent application, the contents of which are incorporated herein in their entirety. U.S. Pat. No. 6,439,136 provides a pulverized solid fuel nozzle tip having a single shell comprised of a ceramic material such as, for example, silicon nitride, siliconized silicon carbide (having a silicon content of between about twenty percent (20%) to sixty percent (60%) by weight, mullite bonded silicon carbide alumina composite, and alumina zirconia composites. 
   The single shell of the ceramic nozzle tip is of a unitary construction, i.e., is formed as a single ceramic piece. It has been found that during normal operating conditions this single shell is subject to cracking due to thermal expansion and contraction, i.e., thermal stresses. As will be appreciated, such a failure results in an economic loss for those utilizing the nozzle tip. Accordingly, a need exists for a ceramic pulverized solid fuel nozzle tip that remedies the deficiencies of the above-described ceramic pulverized solid fuel nozzle tip. 
   OBJECTS OF THE INVENTION 
   It is an object of the present invention to provide a new and improved solid fuel nozzle tip for use in a firing system of the type utilized in pulverized solid fuel-fired furnaces. 
   It is a further object of the present invention to provide a new and improved solid fuel nozzle tip for use in a firing system of the type utilized in a pulverized solid fuel-fired furnace that is comprised of a ceramic material. 
   The above-stated objects, as well as other objects, features, and advantages, of the present invention will become readily apparent from the following detailed description which is to be read in conjunction with the appended drawings. 
   SUMMARY OF THE INVENTION 
   In accordance with one embodiment of the present invention, there is provided a solid fuel nozzle tip. The subject solid fuel nozzle tip, in accordance with this one embodiment of the present invention, is constructed in multiple ceramic sections so as to better withstand thermal stresses. In particular, the first embodiment includes a first ceramic shell and a second ceramic shell. The ceramic from which the first and second shells are made could be any type of ceramic suitable for use in a solid fuel nozzle tip. However, in certain aspects, the ceramic is from a group of ceramic materials including silicon nitride, siliconized silicon carbide (having a silicon content of between about twenty percent (20%) to sixty percent (60%) by weight), mullite bonded silicon carbide alumina composite, reaction-bonded silicon carbide, and alumina zirconia composites. 
   The first ceramic shell and the second ceramic shell are configured to be interconnected with one another. More particularly, each ceramic shell has an inlet end and an outlet end. The outlet end of the first ceramic shell is configured to be interlocked with the inlet end of the second ceramic shell. In this manner, pulverized solid fuel entering the first ceramic shell&#39;s inlet end, from a pulverized solid fuel nozzle, passes through the outlet end of the first ceramic shell and into the inlet end of the second ceramic shell. 
   In one aspect of this embodiment of the present invention, the first ceramic shell and the second ceramic shells interconnect by at least one dovetail joint. A dovetail joint, which is similar to the connection between two pieces of a jigsaw puzzle, is made up of a tenon, or protrusion, formed in one of the first and second ceramic shells, and a mortise, or recess, formed in the other one of the first and second ceramic shells. Thus, with a dovetail joint, two shells will slide together to interconnect. 
   According to a further aspect of this embodiment of the present invention, the dovetail joint prevents the first and second ceramic shells from moving along a first axis, i.e., in a first direction. A hole is formed through the first ceramic shell and into the second ceramic shell. A connector, such as a pin or other straight object, may be inserted into the hole to prevent movement of the first and second shells along a second axis different than the first axis. 
   In yet another aspect of this embodiment of the present invention, the solid fuel nozzle tip includes a third ceramic shell. This third ceramic shell is configured to be interconnected with the second ceramic shell. Similar to the discussion above, the outlet end of the second ceramic shell is configured to be interlocked with an inlet end of the third ceramic shell. Thus, solid fuel passes through the outlet end of the second ceramic shell and into the inlet end of the third ceramic shell. 
   According to a further aspect of this embodiment of the present invention, the solid fuel nozzle tip includes at least one splitter plate. A splitter plate, in this aspect, is adapted to be inserted into the second and third ceramic shells. In other words, such a splitter plate would reside within the shells and be supported by the shells themselves. A splitter plate could be any type of splitter plate known in the art, including, but not limited to, a splitter plate having one or more tapered edges, and/or a low NO x  splitter plate. Preferably, the at least one splitter plate is ceramic. In an especially beneficial further aspect, the at least one splitter plate restrains movement of the second and third ceramic shells. That is, the shells cannot slide apart if a splitter plate is present. 
   In another embodiment of the present invention, a solid fuel nozzle tip for use in cooperative association with a pulverized solid fuel nozzle of a firing system of a pulverized solid fuel-fired furnace is provided. This embodiment includes three ceramic shells, similar to those discussed above. An inlet end of the first ceramic shell is interconnected with the pulverized solid fuel nozzle. An outlet end of the first ceramic shell is interconnected with the inlet end of the second ceramic shell, and an outlet end of the second ceramic shell is interconnected with an inlet of the third ceramic shell. Thus, pulverized solid fuel that enters the inlet end of the first ceramic shell will exit the outlet end of the third ceramic shell. In further aspects of this embodiment, multiple dovetail joints are provided for interconnecting the three ceramic shells. In an even further aspect, at least one splitter plate is disposed within the three ceramic shells that are interconnected with dovetail joints. And finally, in addition to the dovetail joints, the first and second ceramic shells are also restrained with at least one pin that extends through the first ceramic shell and into the second ceramic shell. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order to facilitate a fuller understanding of the present invention, reference is now made to the appended drawings. These drawings should not be construed as limiting the present invention, but are intended to be exemplary only. 
       FIG. 1   a  is a diagrammatic representation in the nature of a vertical sectional view of a pulverized solid fuel-fired furnace embodying a firing system with which a solid fuel nozzle tip in accordance with the present invention may be utilized. 
       FIG. 1   b  is a simplified depiction of a pulverized solid fuel nozzle of the type employed in the firing system of the pulverized solid fuel-fired furnace that is illustrated in  FIG. 1  that may be utilized with the solid fuel nozzle tip of the present invention. 
       FIG. 2  is a first side view of the solid fuel nozzle tip of the present invention. 
       FIG. 3  is an expanded side view of the solid fuel nozzle tip illustrated in  FIG. 2 . 
       FIG. 4  depicts the interconnection of two sections of the solid fuel nozzle tip illustrated in  FIG. 2 . 
       FIG. 5  is a second side view of the solid fuel nozzle tip of the present invention showing splitter plates. 
       FIG. 6  is another view of the solid fuel nozzle tip of the present invention showing the splitter plates of  FIG. 5 . 
       FIG. 7  is a third side view of the solid fuel nozzle tip of the present invention showing holes for pins. 
       FIG. 8  depicts the solid fuel nozzle tip of the present invention with the pins. 
   

   DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
     FIG. 1   a  depicts an exemplary pulverized solid fuel-fired furnace, generally designated by reference numeral  10 , with which the new and improved pulverized solid fuel nozzle tip disclosed herein can be utilized. Inasmuch as the nature of the construction and the mode of operation of pulverized solid fuel-fired furnaces are well known to those skilled in the art, it is not deemed necessary to set forth herein a detailed description of the pulverized solid fuel-fired furnace  10 . Rather, a description of the nature of the components of the pulverized solid fuel-fired furnace  10  is deemed to be sufficient. For a more detailed description of the nature of the construction and the mode of operation of the components of the pulverized solid fuel-fired furnace  10  and of a firing system with which the pulverized solid fuel-fired furnace  10  is suitably provided, one may have reference to the prior art, i.e., in the case of the pulverized solid fuel-fired furnace  10  to U.S. Pat. No. 4,719,587, which issued Jan. 12, 1988 to F. J. Berte and which is assigned to the same assignee as the present patent application and, in the case of the firing system with which the pulverized solid fuel-fired furnace  10  is suitably provided, to U.S. Pat. No. 5,315,939, which issued May 31, 1994 to M. J. Rini et al. and which is assigned to the same assignee as the present patent application. 
   Referring further to  FIG. 1   a , the pulverized solid fuel-fired furnace  10  includes a burner region  14 . It is within the burner region  14  that, in a manner well-known to those skilled in this art, combustion of the pulverized solid fuel and air is initiated. The hot gases that are produced from the combustion rise upwardly in the pulverized solid fuel-fired furnace  10 . During the upwardly movement thereof the hot gases, in a manner well-known to those skilled in this art, give up heat to fluid passing through tubes (not shown in the interest of maintaining clarity of illustration in the drawing) that in conventional fashion line all four of the walls of the pulverized solid fuel-fired furnace  10 . Then, the hot gases exit the pulverized solid fuel-fired furnace  10  through the horizontal pass  16 , which in turn leads to the rear gas pass  18 . Both the horizontal pass  16  and the rear gas pass  18  commonly contain other heat exchanger surfaces (not shown) for generating and superheating steam. Thereafter, the steam commonly is made to flow to a turbine (not shown), which forms one component of a turbine/generator set (not shown), such that the steam provides the motive power to drive the turbine (not shown) and thereby also the generator (not shown), which in known fashion is cooperatively associated with the turbine, such that electricity is thus produced from the generator (not shown). 
   The subject firing system with which the pulverized solid fuel-fired furnace  10  is provided includes a housing preferably in the form of a main windbox, which is identified in  FIG. 1   a  by the reference numeral  20 . In a manner well-known to those skilled in the art, the windbox  20  is provided with a plurality of air compartments (not shown) through which air supplied from a suitable source thereof (not shown) is injected into the burner region  14 . In addition, the windbox  20 , also in a manner well-known to those skilled in the art, is provided with a plurality of fuel compartments (not shown) through which solid fuel is injected into the burner region  14 . The solid fuel is supplied to this plurality of fuel compartments (not shown) by means of a pulverized solid fuel supply means, denoted generally by the reference numeral  22 . To this end, the pulverized solid fuel supply means  22  includes a pulverizer  24  and a plurality of pulverized solid fuel ducts  26 . In a fashion well-known to those skilled in the art, the pulverized solid fuel is transported through the pulverized solid fuel ducts  26  from the pulverizer  24  to which the pulverized solid fuel ducts  26  are connected in fluid flow relation to the previously mentioned plurality of fuel compartments (not shown). Although not shown in the interest of maintaining clarity of illustration in the drawing, the pulverizer  24  is operatively connected to a fan (not shown), which in turn is operatively connected in fluid flow relation with the previously mentioned plurality of air compartments (not shown), such that air is supplied from the fan (not shown) to not only the aforesaid plurality of air compartments (not shown) but also to the pulverizer  24  whereby the pulverized solid fuel supplied from the pulverizer  24  to the aforesaid plurality of fuel compartments (not shown) is transported through the pulverized solid fuel ducts  26  in an air stream in a manner which is well known to those skilled in the art of pulverizers. 
   Referring next to  FIG. 1   b , there is depicted therein a pulverized solid fuel nozzle, denoted generally therein by the reference numeral  34 . In accordance with the illustration thereof in  FIG. 1   b , the pulverized solid fuel nozzle  34  is depicted as being associated with a solid fuel nozzle tip  12  which could be constructed in accordance with the present invention, or otherwise. A pulverized solid fuel nozzle  34 , in a manner well-known to those skilled in the art, is suitably supported in mounted relation within each of the plurality of fuel compartments (not shown) to which reference has been had hereinbefore. In this regard, a schematic representation of one of the plurality of fuel compartments (not shown) is denoted in  FIG. 1   b  by the reference numeral  36 . 
   Any conventional form of mounting means suitable for use for such a purpose may be employed to mount the pulverized solid fuel nozzle  34  in the fuel compartment  36 . The pulverized solid fuel nozzle  34 , as best understood with reference to  FIG. 1   b , includes an elbow-like portion denoted by the reference numeral  38  that is designed, although it has not been depicted in  FIG. 1   b  in the interest of maintaining clarity of illustration therewithin, to be operatively connected at one end, i.e., the end thereof denoted in  FIG. 1   b  by the reference numeral  40 , to a pulverized solid fuel duct  26 . The other end, i.e., that denoted by the reference numeral  42 , of the elbow-like portion  38 , as seen with reference to  FIG. 1   b  of the drawing, is operatively connected through the use of any conventional form of fastening means suitable for use for such a purpose to the longitudinally extending portion, denoted by the reference numeral  44 . The length of the longitudinally extending portion  44  is such as to essentially correspond to the depth of the fuel compartment  36 . 
     FIG. 2  depicts a ceramic pulverized solid fuel nozzle tip  201  usable with the pulverized solid fuel nozzle  34  in accordance with the present invention. The pulverized solid fuel nozzle tip  201  incorporates the advantages of the nozzle tip disclosed in U.S. Pat. No. 6,439,136 while overcoming the deficiencies thereof noted above. The pulverized solid fuel nozzle tip  201  includes three segments, inlet segment  205 , middle segment  207 , and outlet segment  209 , that connect in an interlocking dovetail fashion and through which a pulverized fuel and air mixture is directed into burner region  14 . 
   To better illustrate the manner in which the three segments of the pulverized solid fuel nozzle tip  201  interlock, attention is directed to  FIG. 3  and  FIG. 4 .  FIG. 3  depicts the three segments not connected with one another. As shown in  FIG. 3 , inlet segment  205  includes protrusion  301 . Protrusion  301  is configured to slideably connect with recess  305  which is formed in middle segment  207 . Middle segment  207  also includes protrusion  307  which is configured to slideably connect with recess  310  formed in outlet segment  209 .  FIG. 4  depicts middle segment  207  and outlet segment  209  being slid together. 
   Due to the dovetail configuration, the multiple segments float in relation to one another. This floating allows the pulverized solid fuel nozzle tip  201  to accommodate thermal stresses caused by exposure to the heat of normal operating conditions without cracking because those forces are apportioned among the multiple segments such that no one segment is subjected to more thermal expansion and contraction than it can accommodate. Also, the pulverized solid fuel nozzle tip  201  accommodates the thermal stresses because each segment is isolated from adjoining segments due to the gaps between adjoining segments. 
   Preferably, the ceramics employed in the solid fuel nozzle tip  201  are silicon nitride, siliconized silicon carbide (having a silicon content of between about twenty percent (20%) to sixty percent (60%) by weight), mullite bonded silicon carbide alumina composite, reaction-bonded silicon carbide, or alumina zirconia composites. However, any ceramic capable of withstanding operating conditions to which a solid fuel nozzle tip is subjected may be utilized. In the selection of the ceramic for the solid fuel nozzle tip  201 , some ceramics may have a more desirable property in one respect while having a less desirable property in another respect as compared to another ceramic or other ceramics under consideration. Thus, it may not be possible to identify a particular ceramic as significantly more desirable than the other ceramics which may be also suitable for employment in the solid fuel nozzle tip  201 . However, to the extent possible, it is desirable that the strength of the ceramic as measured, for example, by a flexural strength test, be relatively high so as to enable the ceramic to more successfully resist deformation. Also, in applications in which pulverized solid fuel being injected through the solid fuel nozzle tip  201  is itself at a relatively high feed temperature such as, for example, pulverized coal which has been pre-heated, or in applications in which the solid fuel nozzle tip  201  is exposed to a relatively high temperature at its outlet such as, for example, an application in which the solid fuel nozzle tip  201  is mounted in a windbox of a pulverized coal fuel-firing furnace, it may be particularly desirable to select a ceramic which has a good resistance to thermal shock. A ceramic having a good resistance to thermal shock may be characterized, for example, by a high thermal conductivity and a low coefficient of thermal expansion. 
   One advantage of composing the solid fuel nozzle tip  201  of a ceramic material of the group of ceramic materials comprised of ceramics having silicon nitride, siliconized silicon carbide (having a silicon content of between about twenty percent (20%) to sixty percent (60%) by weight), mullite bonded silicon carbide alumina composite, reaction-bonded silicon carbide, or alumina zirconia composites is that these ceramics are more likely than other ceramic materials to better tolerate the temperature differentials typically experienced by a pulverized solid fuel nozzle tip. These temperature differentials are the differences in temperature experienced by the pulverized solid fuel nozzle tip within a predetermined period. Relatively rapid or large temperature fluctuations can stress a pulverized solid fuel nozzle tip comprised of ceramic material to failure although, as noted, the ability of the pulverized solid fuel nozzle tip to withstand such stresses can be improved by appropriate selection of the ceramic material. 
   The pulverized solid fuel nozzle tip  201  also includes, as shown in  FIG. 5 , splitter plates  501 A and  501 B, preferably also ceramic. Although two individual splitter plates are disclosed herein, it is to be understood that a different number of individual splitter plates could be utilized without departing from the essence of the present invention. 
   As shown in  FIG. 5 , each splitter plate  501 A and  501 B is recessed within the exit plane  504  of the pulverized solid fuel nozzle tip  201 . By being so recessed each splitter plate  501 A and  501 B is thereby removed as a surface susceptible to potential deposition arising from the firing zone, as will be recognized by one of ordinary skill in the art. Also, such recessing of a splitter plate is effective for purposes of providing some cooling to that splitter plate means by virtue of the shielding effect provided thereto by the outlet segment  209 . In addition, such recessing of splitter plates  501 A and  501 B results in a splitter plate that is shorter in length, which in turn thus has the effect of reducing the contact surface for heat transfer thereto as well as reducing the contact surface for the deposition of particles thereon. 
   In addition, each of splitter plates  501 A and  501 B is also characterized in a second respect by the fact that the ends of splitter plates  501 A and  501 B closest to the exit plane  504 , i.e., the trailing edge of a splitter plate, is tapered by a predetermined amount to prevent the separation of the primary air that flows on either side thereof. As will be understood, if such separation of the primary air were to occur, it could have the effect of creating additional unwanted flow recirculation. Such tapering of the trailing edges of splitter plates  501 A and  501 B is effective in reducing the recirculation region that has served to adversely affect the operation of prior art forms of solid fuel nozzle tips, which are characterized by the fact that they embody a blunt faced trailing edge. Secondly, such tapering of the trailing edges of the splitter plates  501 A and  501 B is effective in reducing the shed vortices that are created by blunt faced trailing edges. If the splitter plates  501 A and  501 B were to embody blunt ends, the recirculation region induced thereby would operate to draw hot particulate back thereto and thus would have the effect of creating or exacerbating the solid fuel deposition phenomena. Such a recirculation region is also capable of providing conditions conducive to combustion, thus creating flames within the recirculation region, which would have the effect of raising temperatures and further exacerbating the deposition problem. 
   Alternatively, though not depicted in the FIGS., the splitter plates  501 A and  501 B could be configured as low NO x  splitter plates for minimizing carbon in the flyash produced from burning the pulverized solid fuel. As will be understood with reference to U.S. Pat. No. 6,439,136, in such a case integrally formed with each splitter plate  501 A and  501  B are a first set of bluff bodies and a second set of bluff bodies. The first set of bluff bodies is cooperatively associated with a splitter plate so as to project upwardly relative thereto, i.e., so as to project above the centerline of that splitter plates. In contrast, the second set of bluff bodies is cooperatively associated with the splitter plate so as to project downwardly relative thereto, i.e., so as to project below the centerline of that splitter plate. When present, the bluff bodies are formed at the trailing edge of a respective one of the splitter plates  501 A and  501 B. 
   Each bluff body is withdrawn 0.5 to 2.0 inches from both the outlet segment  209  and the exit plane  504  of the pulverized solid fuel nozzle tip  201  such that the high turbulence region of the solid fuel stream is encased within a low turbulence solid fuel “blanket”. The effect of the bluff bodies is to maximize turbulence and vortex shedding while yet maintaining the ability of the pulverized solid fuel nozzle tip  201  to tilt and to direct the solid fuel stream. As desired, a greater number of low NO x  splitter plates than two could, as desired, be utilized. 
   The splitter plates  501 A and  501 B, whether configured as low NO x  splitter plates or not, also serve to lock together middle segment  207  and outlet segment  209  utilizing recesses, each designated  505 , formed in middle segment  207  and outlet segment  209 . As shown in  FIG. 6 , after middle segment  207  and outlet segment  209  have been slid together, splitter plates  501 A and  501 B are slid into the recesses  505 . Each splitter plate  501 A and  501 B includes a pair of guides, each designated  601 , which each fit into a recess  505 . When inserted into place, each of splitter plates  501 A and  501 B prevents middle segment  207  and outlet segment  209  from disengaging. 
     FIG. 7  depicts inlet segment  205  both interlocked with and secured to middle segment  207 . Holes, each designated  705 , are formed diagonally through inlet segment  205  and into middle segment  207 . Preferably, there are four holes  705 , however, as desired, a different number of holes  705  could be utilized. As depicted in  FIG. 8 , a pin, each designated  805 , is inserted into each hole  705  to secure inlet segment  205  to middle segment  207 . As desired, a grout suitable for the operating environment in which the pulverized solid fuel nozzle tip  201  will be placed can be placed in each hole  705  after a pin  805  has been inserted therein. Further, and also as desired, a grout can be placed in the gap between each of the multiple segments. 
   Holes  810 A and  810 B are formed in the inlet segment  205  for pivotally mounting the pulverized solid fuel nozzle tip  201  to a pulverized solid fuel nozzle  34  in a fuel compartment of the furnace  10  with which it is associated. As desired, mounting brackets, such as those disclosed in U.S. Pat. No. 6,439,136 may be utilized with holes  810 A and  810 B. However, any other known mounting technique may be utilized, as desired. 
   The present invention is not to be limited in scope by the specific embodiments described herein. Indeed, various modifications of the present invention in addition to those described herein will be apparent to those of skill in the art from the foregoing description and accompanying drawings. Thus, such modifications are intended to fall within the scope of the appended claims.