US3746499A

US3746499A - Staged air burner with swirling auxiliary air flow

Info

Publication number: US3746499A
Application number: US00217349A
Authority: US
Inventors: R Guerre; R Ruland
Original assignee: Exxon Research and Engineering Co
Current assignee: ExxonMobil Technology and Engineering Co
Priority date: 1970-07-06
Filing date: 1972-01-12
Publication date: 1973-07-17
Anticipated expiration: 1990-07-17
Also published as: FR2168772A6

Abstract

A chamberless, high intensity staged air burner especially suited for the incineration and combustion of contaminated fuels and waste streams by achieving a high, concentrated degree of mixing and, therefore, a high temperature, in a relatively small but structurally unconfined volume. The burner utilizes the principle of vortex air flow from an air induction chamber together with swirling auxiliary air flow to achieve a high degree of recirculation local to the point of fuel injection, to provide intimate mixing of fuel and air, precise control over the flame envelope. Utilizing the air required for combustion in the foregoing manner eliminates the need for a refractory-lined chamber which otherwise would be required to confine the combustion process in order to generate the extreme temperatures sometimes required for complete incineration. The swirling auxiliary air flow is obtained by providing a plurality of circumferentially arranged swirl vanes in way of the portion of inlet air directed through the auxiliary air passageways. These swirl vanes may be mounted for limited movement or can be stationarily secured in the desired position.

Description

United States Patent 1 Guerre et al.

[ 1 STAGEI) AIR BURNER WITH SWIRLING AUXILIARY AIR FLOW [75} Inventors: Robert P. Guerre, Dover;

Ross R. Ruland, Hopatcong, both ofNJ.

[73 l Assignee: Esso Research and Engineering Company [22] Filed: Jan. 12, 1972 [2]] Appl. No.: 217,349

Related U.S. Application Data [63] Continuation-in-part of Ser. No. 52,341, July 6, 1970,

Pat. No. 3,671,173.

[52] U.S. Cl. 431/182 [51] Int. Cl. F23m 9/08 [58] Field of Search 431/182, 183, 185, 431/188 [56] References Cited UNITED STATES PATENTS 2,219,696 10/1940 Mueller et al. 431/185 X 3,208,502 9/1965 Carlson.... 431/188 3,301,305 1/1967 Kimmel 431/183 X 3,226,038 12/1965 Brady et al. 431/183 Primary Examiner-Edward G. Favors Attorney- Leon Chasan, F. Donald Paris et al.

[ 1 July 17, 1973 [57] ABSTRACT A chamberless, high intensity staged air burner especially suited for the incineration and combustion of contaminated fuels and waste streams by achieving a high, concentrated degree of mixing and, therefore, a high temperature, in a relatively small but structurally unconfined volume. The burner utilizes the principle of vortex airflow from an air induction chamber together with swirling auxiliary air flow to achieve a high degree of recirculation local to the point of fuel injection, to provide intimate mixing of fuel and air, precise control over the flame envelope. Utilizing the air required for combustion in the foregoing manner eliminates the need for a refractory-lined chamber which otherwise would be required to confine the combustion process in order to generate the extreme temperatures sometimes required for complete incineration The-swirling auxiliary air flow is obtained by providing a plurality of circumferentially arranged swirl vanes in way of the portion of inlet air directed through the auxiliary air passageways. These swirl vanes may be mounted for limited'movement or can be stationarily secured in the desired position.

16 Claims, 8 Drawing Figures Pmmm JIJU 1 ma sum 1 or 3 :IE 1

PAIENIED- 1 m1:

SHEET 2 [IF 3 STAGED AIR BURNER WITH SWIRLING AUXILIARY AIR FLOW CROSS-REFERENCE TO RELATED A PPLICATIONS This application is a continuation-in-part of copending U. S. Patent Application Ser. No. 52,341, filed July 6, 1970, now Pat. No. 3,671,173 and assigned to the assignee of the present application. The new subject matter contained herein is directed the swirling nature of the auxiliary or secondary air flow and the structure associated therewith for accomplishing the same in combination with a chamberless high intensity vortex burner such as disclosed in Ser. No. 52,341, which is herein incorporated by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention In general the present invention relates to chamberless, high intensity vortex burners of the staged air type and more particularly to a novel and improved vortex burner which employs swirling auxiliary air flow.

2. Description of the Prior Art Typical prior art high intensity construction burner constructions generally include some sort of combustion chamber which is required to contain and confine the burning process to achieve a high degree of mixing and completeness of combustion. The heated walls of the combustion chamber aid in the combustion process by radiating heat from the chamber walls back toward the flame. These walls or a choke-type throat construction aid in containment and shaping of the flame by restricting the tendency of the gases to expand and limiting the flames radial expansion.

Heretofore, prior art burners have employed secondary swirling air, such as disclosed in U. '8. Pat. No. 3,301,305. However, the construction, arrangement and operation of these typical prior art burners difiers sufficiently from the present invention so as to make the results obtained by the present invention unobtainable in the prior art. Such prior art constructions are not designed so that combustion can'occur in the absence of a combustion chamber.

SUMMARY OF THE INVENTION of recirculation local to the point of fuel injection.

In accordance with the present invention there is provided a novel and improved construction for high intensity burners wherein the need for a combustion chamber is completely eliminated by virtue of the employment of auxiliary air stream flow to control, contain and shape the flame envelope and simultaneously provide adequate turbulences for the required air/fuel mixing. By imparting a swirl or spin to the auxiliary air flow the tendency of the primary vortex air flow is restricted, which results in improved ability of the burner to control and shape the flame envelope, as. well as enhancing the air/fuel mixture. The auxiliary air flow may be spun in the same general direction as the vortexing primary air flow or in a countercurrent direction thereto. The burner is constructed and arranged such that the inlet air stream flows in predetermined precise part through the swirl chamber while the remaining portion of the inlet air stream flows through one or more auxiliary passageways or gaps provided so that the secondary or auxiliary air flow will shape the flame inwardly to control its expansion, restrain the limits of flame expansion and to keep the contaminated fuels off the small amount of refractory surrounding the gap so as to maintain the integrity of the refractory. The momentum of the air flow through the gap is sufficient to enable it to mix with the fuels so that complete combustion is achieved within a short distance relative to the point of fuel injection, thereby to provide a relatively superior, shorter flame which obtains a reduction in flame impingement. A plurality of swirl vanes are provided in way of the air gap in order to impart a spinning or swirling motion to the secondary air flow and to control the rate of secondary airflow. Throughout this disclosure the term primary air flow is intended to mean that air closest to the fuel supply. The terms secondthe air flow(s) other than the primary flow to accomplish the results outlined above. The important characteristic to keep in mind throughout this invention is that the gap air flow must be the dominant factor, that is, it must be sufficiently strong to resist expansion of the vortex flow, which according to the present invention functions to stabilize the flame and tip only. Thus, it is apparent that at least percent of the air flow must be through the gap(s).

In the preferred embodiment of the invention preferably only a single auxiliary air flow is employed to obtain the desired flame quality. The primary air flow is utilized to create a vortex flow region in the immediate vicinity of the fuel supply, which may comprise an oil or gas gun. This characteristic of the burner is essential for good flame quality and stability, especially when utilizing heavy oils. The remainder of the inlet air flow enters through an annular gap disposed about the vortex air flow inducing means to control the limit of expansion of the flame and to create the desired pattern of hot gas/flame envelope and thus, the burner requires no combustion chamber. Although either preheated or ambient inlet air may be employed, by using preheated inlet air a relatively small amount of gap air flow bounces off the fuel rich mixture it is designed to intersect with, thus obtaining the desired combustion and permitting the use of only a single air gap. It is within the scope of this invention, however, to employ multiple air gaps such as disclosed in applicants aforementioned copending application. According to the present invention the refractory material which is located below the air gap is subjected to a vortex wash plus a sub-stoichiometric air/fuel ratio (that is, a fuel rich mixture) so that the temperature thereof is relatively low so as to obtain relatively little heat release along its surface and therefore, the refractory has a relatively high life expectancy even when relatively bad fuels are employed. The vortex wash aids in cooling the refractory surface and is insufl'icient to obtain combustion until the air/fuel mixture is contacted by the auxiliary air flow. Typical of the advantages flowing from such the lack of the necessity for a refractory combustion chamber, which means that even under the worst conditions, a nonexistent refractory cannot be deleteriously affected. In general, the overall construction is simplified since it is not as sensitive to aerodynamic ratios as is true in prior art situations discussed heretofore.

Accordingly, it is a primary object of the present invention to provide a novel chamberless high intensity vortex burner employing auxiliary air flow.

Another object of the present invention is to provide a novel and improved chamberless, high intensity vortex burner which retains the advantages of present day superior high intensity burners, while eliminating the need for a combustion chamber by utilizing the principle of air stream momentum to control and contain the flame envelope.

A further object of the present invention is to provide a chamberless high intensity burner which utilizes a predetermined portion of the inlet air flow to create a vortex flow region in the immediate vicinity of the fuel supply and includes at least one annular gap located proximate the vortex region to provide a passageway for an auxiliary swirling air flow to control the limit of expansion of the flame.

Having in mind the above and other objects that will be evident from an understanding of this disclosure, the invention comprises the construction and arrangement as illustrated in the presently preferred embodiments of this invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to fully understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a preferred embodiment of a chamberless high intensity burner constructed and arranged in accordance with the present invention;

FIG. 2 is a vertical-sectional view of the burner of FIG. 1 taken substantially along the line 22 of FIG.

FIG. 3 is a horizontal-sectional view taken substantially on the line 3-3 of FIG. 2;

FIG. 4 shows a portion of FIG. 3 with the vanes moved clockwise from the position shown in FIG. 3;

FIG.-5 is a cross-sectional taken substantially on the line 5--5 of FIG. 4;

FIG. 6 is a cross-sectional view of the vane and guide pins taken substantially on the line 6-6 of FIG. 4;

FIG. 7 is a cross sectional view of the push rod taken substantially on the line 77 of FIG. 4; and

FIG. 8 is a perspective view of a vane constructed and arranged according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Having reference to the drawings wherein similar parts are designated by like reference numerals, FIGS. 1 through 8 illustrate in detail a preferred embodiment of the present invention. In FIG. 1 there is shown a chamberless high intensity vortex burner generally designated l0 maintained in a furnace floor or wall 11 by suitable welds or brackets (not shown). The burner comprises a cylindrical open-ended burner casing 12 (see FIG. 2) made of carbon steel construction and lined internally with a block type insulation 13 secured to the interior of the casing 12 by a suitable insulation adhesive. When preheated air is employed the insulation 13 provides protection against a person inadvertently touching the hot casing. The casing 12 includes a radially disposed air duct 14 for providing an inlet opening 15 to receive the air flow designated by the arrow, which may be ambient or preheated. Preheated air, if employed, may be supplied by conventional means (not shown) such as a standard air preheated or other suitable type of conventional preheater.

The casing 12 is provided at its bottom with a cover plate 16. A block insulation 17 is secured to the interior surface of the cover plate 16. The cover plate 16 extends radially outward beyond the intemal insulation 17 to provide an apertured flange 18 which facilitates mounting of the cover plate 16 to the burner casing 12 by means of nuts and bolts generally designated 19, as shown in FIG. 2. The cover plate 16 is formed with a central opening 20 having a packing sleeve 21 disposed therein for mounting air flow inducing means including a casing 22 of conventional construction in an air inlet plenum chamber 23, for receiving a predetermined portion of the inlet air flow. The air flow from the plenum chamber flows in two directions. One flow is tangential through the tangentially arranged air ducts 24 such that the inlet tangential air flow through the cham' her or casing 22 is modified to include an axial direc tion component of vortex air flow. The other air flow is a secondary or auxiliary air flow through the air gap as described hereinafter. The chamber 22 is mounted conventionally as best illustrated in FIG. 2, which also illustrates the general air flow pattem. The chamber 22 has associated therewith an upper radially extending annular seat or support plate 25 (located above the ducts 24). The plate 25 includes a plurality of radially spaced apertures 26 spaced 90 apart. An annular primary or lower burner tile 27 made. of a suitable, high temperature castable refractory material seats on the support plate 25 and may be secured thereto by a suitable refractory cement and restrained radially by peripherally disposed upstanding metal clips 28 (see FIG. 2) welded to the plate 25. The upper surface of the primary burner tile 27 has a substantially pyramidal shape comprising an inner outwardly sloping surface 29 joined to form an apex with an outer inwardly sloping surface 30. A centrally open annular floor plate 31 is provided with downward extending threaded bolts or mounting rods 32 for pressing through corresponding ones of the apertures 26 to mount the support plate 25 at a distance which is adjustable relative to the floor plate 31. Thus, the primary burner tile 27 also is vertically adjustable. The

members

25 and 31 are fastened by means of conventional nuts which thread onto the threaded portion of the rods 32 extending through the I apertures 26. The floor plate 31 has secured thereto by a suitable refractory cement or the like, a secondary or upper annular burner tile 33 which is also made of a high temperature castable refractory material. The tile 33 has an inner annular surface of pyramidal shape comprising an upper annular surface 34 having a slope substantially similar to and when mounted coplanar with the surface 29, and a bottom or lower annular surface 35 whose slope is parallel with that of the surface 30 and is disposed in spaced parallel relation to the surface 30 as shown in FIG. 2. When mounted as shown in FIG. 2 the

surfaces

35 and 30 form a continuous uni form annular air gap 36. The width of the gap or auxiliary air passageway 36 may be adjusted by changing the vertical disposition of the support plate 25 relative to the floor plate 31. By closing the air gap the velocity of the auxiliary or secondary air flow may be controlled, that is, made greater by closing the gap or lessened by making the gap wider.

Typically, in operation, a predetermined precise portion of the inlet air flow enters through the air ducts 24 of the casing 22, for example 25 to 50 percent, which comprises the primary air flow and creates a strong vortex flow which forces the hot gases to recirculate back to the fuel spray, which enters through the fuel gun shown in part schematically in dotted lines by reference character 37, thus heating it and aiding in combustion. The remaining 50 to 75 percent of the inlet air flow enters through the continuously uniform annular air gap 36. This auxiliary or secondary air flow shapes the flame inwardly to maintain the contaminated fuels off the surrounding refractory material, and further produces a high turbulent zone for mixing the fuel and air to achieve complete combustion within a relatively short distance of the fuel gun. By imparting a swirling or spinning motion to the secondary air flow, in the manner as described hereinafter, the tendency of the primary vortex air flow to expand radially upon exiting is restricted which goes toward improving flame quality. This secondary swirl may be countercurrent to the direction of helical primary vortex air. Thus, the vortex air flow achieves a' high degree of recirculation local to the point of fuel injection together with one or more coaxially disposed annular-shaped streams of air to provide intimate mixing of fuel and air, as well'as to shape, control and contain the flame envelope. Air flow through the annular gap 36 controls the limit of expansion of the flame and creates the desired pattern of hot gas/flame envelope. The fuel supply may comprise conventional means 37 such as a center fired gas gun unit or a standard oil gun. The burner is provided with the usual pilot guide tube (not shown) and pilot light-off tube (not shown). Extending through the central opening 20 of the cover plate 16 is a bottom flanged gun guide tube 38, which is received in the sleeve 21.

In the event that the preferred embodiment utilizes preheated air, a typical temperature range of the air would be about 500 750F. Since air is the main force in this burner construction, its flow must be maintained in a substantially uniform manner. Essentially this means that any obstruction such as coke deposit, refractory pieces or low pressure may cause'an unbalancing of the flame and thereby create further overheating or additional deposits to one side or the other of the burner so that eventually the entire burner may fail. Accordingly, the present burner has been constructed and arranged so that interference with air flow is minimized. It is most desirable to maintain the annular gap 36 uniform as any non-symmetry will cause the flame to lean more so toward the favored'side.

To impart the spinning or swirling motion to the secondary air flow, there is provided a plurality of swirl vanes 39. As shown in FIGS. 1 through 3 these vanes 39 are disposed in way of the entry to the secondary air gap 36 and are oriented such that they spin the secondary air flow in the desired direction. In the preferred embodiment, the vanes are mounted on a rotatable plate 40 which is designed to sit on the support plate 25 between the radially spaced mounting rods 32. These mounting rods effectively function as guides for the plate 40 in the event that the plate is moved in order to change the disposition of the vanes 39. The plate 40 is thus prevented from undesirable inward and outward radial movement. Each of the vanes 39 comprises a rectangular shaped elongated portion 41 and located at one end thereof a tubular or bored member 42. The elongated portion 41 either may be welded to the tubular member 42 or the vane may comprise a single piece of metal roll-formed into the desired configuration. Circumferentially disposed about the rotating plate 40 at about thirty degree intervals are a plurality of vane mounting pins 43 (see FIG. 5). These mounting pins may be secured to the plate 40 by means of a countersunk screw 44 (also see FIG. 5) extending from the bottom through the plate into threaded engagement with the mounting pin. Other suitable means (e.g., welding, etc.) may be employed to secure the mounting pin to the rotatable plate. As shown in FIG. 5, the tubular portion 42 of the vane 39 is slid over the corresponding mounting pin 43 for engagement therewith. To restrict movement of the vanes, there are provided circumferentially about the periphery of the support plate 25 a 47. As shown in FIG. 3.,which illustrates one position of the vanes, the rotatable plate 40 can be moved in a counterclockwise direction. FIG. 3 illustrates the extreme outer and inner positions of

rods

46, 47 respectively. The swirl vanes 39 in FIG. 3 are disposed for imparting a counterclockwise spinning motion to the secondary air. In the embodiment shown the spinning mo- I tion of the secondary air is in the same direction (counterclockwise) as that of the primary vortex air flow. However, it is to be understood that .the disposition of the swirl vanes can be such as to impart a countercurrent spinning motion (which in the illustrated embodiment would be clockwise) to the secondary air flow opposite that of the primary vortex air flow. Each of the

push rods

46 and 47 is mounted in a similar manner and thus only the mounting of one is necessary for an understanding of that particular feature of the present invention. The external or outer end of each push rod is provided with a manually engagable member disposed perpendicular to the lengthof the rod. The inner end of each push rod is secured to a fastening member 48 which extends radially outward from the rotatable plate I 40. The member 48 can be secured to the plate 40 by 7 illustrates that the inner end of the push rod is secured by conventional means generally designated 49,

which may comprise nuts and bolts, to the fastening member 48. To facilitate sliding movement of the push rod through the burner casing 12 and the interior insulation 13, there is provided anopening in the casing 12 and the insulation 13, in which is mounted a tubular coupling member 49. The coupling 49 is secured to the burner casing by means of a weld such as shown at 50. As shown in FIG. 3, the push rod 46 is disposed in its outermost position, while the push rod 47 is disposed in its innermost position. FIG. 4 shows the push rod 46 urged inwardly and the corresponding movement of the push rod 47 would be outward (not shown). While the swirl vanes 39 have been disclosed in the preferred embodiment as being moveable in order to provide variations in the spining motion imparted to the secondary air flow, it is within the scope of this invention to mount the plate 40 and swirl vanes 39 in a stationary fashion.

Although not illustrated herein, it is also within the scope of the invention to provide a plurality of air gaps for providing a multiplicity of secondary air flows whereupon suitable swirl vanes such as described heretofore may be associated with each of the air gaps for imparting a spinning or swirling motion to all the auxiliary air flow. Alternatively, a single structure may be provided to impart this spinning motion to each of the multiple auxiliary air flows. Various configurations which might employ a plurality of auxiliary air flows are disclosed in the heretofore mentioned copending U.S. application.

According to the present invention there has been provided a burner that obviates the need for a combustion chamber while simultaneously providing for substantially improved flame performance and quality through precise flame control. Although there has been disclosed herein a preferred construction and arrangement of a burner, it should be understood that such disclosure is intended to be representative of a preferred embodiment only and that various changes may be made therein without departing from the clear teachings of the present inventions. Thus, for example, although a single air gap has been described and illustrated, it is within the scope of the invention to employ ness, it is possible to achieve the desired results either with an arrangement including a single air gap or a plurality of air gaps which can range from a horizontal air gap to an air gap disposed at substantially 45 relative to the horizontal and for obtaining substantially longer flames the air gap may be disposed from substantially relative to the horizontal to a vertical air gap. Accordingly, reference should be made to the following appended claims in determining the full scope of the invention.

Having thus set forth the nature of the invention, what is claimed herein is:

l. A chamberless staged-air vortex burner for use in the burning of fuels and adapted to be mounted in a furnace wall having an opening therein comprising in combination, burner casing means having an air inlet adapted for receiving an inlet air flow, air induction chamber means having an outlet and being mounted within said burner casing for receiving a predetermined portion of said inlet air flow and producing a helical vortex primary air flow from said outlet, refractory means mounted in said casing about said chamber outlet, said refractory means including a substantially divergent surface extending outward from the periphery of said outlet to a plane common with the outer surface of said furnace wall, air gap means adapted to receive the remaining portion of said inlet air flow, said air gap means comprising at least one air gap of substantially uniform annular configuration extending through said refractory means and located between said outlet and the plane of said outer surface of said furnace wall in which said burner is to be mounted, means for imparting spinning directional motion to at least a part of the remaining portion of said inlet air flow as it enters said one air gap, said one air gap being angularly disposed relative to the axis of said primary air flow for projecting spinning secondary air flow in a convergent direction toward the primary air flow axis to contain the flame envelope and obtain precise flame control and intimate mixing of fuel and air proximate the point of fuel injection.

2. A vortex burner according to claim 1 wherein said motion imparting means is located radially outward of said chamber outlet directly adjacent the inlet to said one air gap.

3. A vortex burner according to claim 1 wherein said one air gap is angularly disposed to provide convergent upward air flow in an outward direction relative to said chamber outlet.

4. A vortex burner according to claim 1 including means for selectively adjusting the width of said one air gap.

5. A vortex burner according to claim 1 wherein said burner is constructed and arranged such that said air induction means is adapted to receive substantially 25 to 50 percent of said inlet air flow and said air gap means is adapted to receive the remaining portion of said inlet air flow.

6. A vortex burner according to claim 1 wherein said motion imparting means comprises a plurality of movably mounted vanes for imparting a different spinning motion to said secondary air flow.

7. A vortex burner according to claim 1 wherein said motion imparting means are mounted stationarily.

8. A vortex burner according to claim 1 wherein said motion imparting means is arranged to spin the secondary air flow in the same direction as the primary air 9. A vortex burner according to claim 1 wherein said motion imparting means is arranged to spin the secondary air flow in a countercurrent direction to said primary air flow.

10. A vortex burner according to claim 1 wherein said motion imparting means comprises a rotatable plate means located radially outward of said chamber outlet proximate the inlet to said one air gap, spin vane mounted on said rotatable means. 1

11. A vortex burner according to claim 10 including means for guiding said rotatable plate means upon movement thereof.

12. A vortex burner according to claim 10 wherein said spin vanes are mounted for pivotal movement on said rotatable plate means, and including guide means associated with each of said spin vanes for limiting the movement thereof.

l3. A vortex burner according to claim 10 including manually engageable means operably secured to said rotatable plate means for facilitating movement thereof.

14. A chamberless staged-air vortex burner for use in the burning of fuels and adapted to be mounted in a furnace wall having an opening therein comprising in combination, burner casing means having an air inlet adapted for receiving an inlet air flow, air induction chamber means having an outlet and being mounted within said burner casing for receiving a'predetermined portion of said inlet air flow and producing a helical vortex primary air flow from said outlet, a support plate secured radially about said chamber means and extending radially outward therefrom, refractory means mounted on said support plate about said chamber outlet, said refractory means including a substantially divergent surface extending outward from the periphery of said outlet to a plane common with the outer surface of said furnace wall, air gap means adapted to receive the remaining portion of said inlet air flow, said air gap means comprising at least one air gap of substantially uniform annular configuration extending through said refractory means and located between said outlet and the plane of said outer surface of said furnace wall in which said burner is to be mounted, an annular member disposed on said support plate outward of said refractory means, spin vanes mounted on said annular member about said chamber means for imparting spinning motion to at least part of the remaining portion of said inlet air flow, means for restricting movement of said annular member, said one air gap being angularly disposed relative to the axis of said primary air flow for projecting spinning secondary air flow in a convergent direction toward the primary air flow axis to contain the flame envelope and obtain precise flame control and intimate mixing of fuel and air proximate the point of fuel injection.

15. A chamberless staged-air vortex burner for use in the burning of fuels and adapted to be mounted in a furnace wall having an opening therein comprising in combination, burner casing means having an air inlet adapted for receiving an inlet air flow, air induction chamber means having an outlet and mounted within said burner casing for receiving a predetermined portion of said inlet air flow and producing an uninterrupted helical vortex primary air flow from said outlet, refractory means including a substantially divergent surface extending outward from the periphery of said I outlet to a plane common with the outer surface of said furnace wall, air gap means adapted to receive the remaining portion of said inlet air flow, said air gap means comprising at least one air gas of substantially uniform annular configuration extending through said refractory means and located between said outlet and the plane of said outer surface, means for imparting spinning directional motion to at least part of the remaining portion of said inlet air flow as it enters said one air gap, said one air gap being angularly disposed relative to the plane of said outer surface for projecting spinning secondary air flow in an outward direction relative to said outlet of said induction chamber for containment of the flame envelope, whereby intimate mixing of fuel and air is obtained proximate the point of fuel injection.

16. A vortex burner according to claim 1 wherein said one air gap is disposed angularly relative to the plane of said outer surface of said furnace wall.

* III

Claims

1. A chamberless staged-air vortex burner for use in the burning of fuels and adapted to be mounted in a furnace wall having an opening therein comprising in combination, burner casing means having an air inlet adapted for receiving an inlet air flow, air induction chamber means having an outlet and being mounted within said burner casing for receiving a predetermined portion of said inlet air flow and producing a helical vortex primary air flow from said outlet, refractory means mounted in said casing about said chamber outlet, said refractory means including a substantially divergent surface extending outward from the periphery of said outlet to a plane common with the outer surface of said furnace wall, air gap means adapted to receive the remaining portion of said inlet air flow, said air gap means comprising at least one air gap of substantially uniform annular configuration extending through said refractory means and located between said outlet and the plane of said outer surface of said furnace wall in which said burner is to be mounted, means for imparting spinning directional motion to at least a part of the remaining portion of said inlet air flow as it enters said one air gap, said one air gap being angularly disposed relative to the axis of said primary air flow for projecting spinning secondary air flow in a convergent direction toward the primary air flow axis to contain the flame envelope and obtain precise flame control and intimate mixing of fuel and air proximate the point of fuel injection.

8. A vortex burner according to claim 1 wherein said motion imparting means is arranged to spin the secondary air flow in the same direction as the primary air flow.

9. A vortex burner according to claim 1 wherein said motion imparting means is arranged to spin the secoNdary air flow in a countercurrent direction to said primary air flow.

10. A vortex burner according to claim 1 wherein said motion imparting means comprises a rotatable plate means located radially outward of said chamber outlet proximate the inlet to said one air gap, spin vanes mounted on said rotatable means.

13. A vortex burner according to claim 10 including manually engageable means operably secured to said rotatable plate means for facilitating movement thereof.

14. A chamberless staged-air vortex burner for use in the burning of fuels and adapted to be mounted in a furnace wall having an opening therein comprising in combination, burner casing means having an air inlet adapted for receiving an inlet air flow, air induction chamber means having an outlet and being mounted within said burner casing for receiving a predetermined portion of said inlet air flow and producing a helical vortex primary air flow from said outlet, a support plate secured radially about said chamber means and extending radially outward therefrom, refractory means mounted on said support plate about said chamber outlet, said refractory means including a substantially divergent surface extending outward from the periphery of said outlet to a plane common with the outer surface of said furnace wall, air gap means adapted to receive the remaining portion of said inlet air flow, said air gap means comprising at least one air gap of substantially uniform annular configuration extending through said refractory means and located between said outlet and the plane of said outer surface of said furnace wall in which said burner is to be mounted, an annular member disposed on said support plate outward of said refractory means, spin vanes mounted on said annular member about said chamber means for imparting spinning motion to at least part of the remaining portion of said inlet air flow, means for restricting movement of said annular member, said one air gap being angularly disposed relative to the axis of said primary air flow for projecting spinning secondary air flow in a convergent direction toward the primary air flow axis to contain the flame envelope and obtain precise flame control and intimate mixing of fuel and air proximate the point of fuel injection.

15. A chamberless staged-air vortex burner for use in the burning of fuels and adapted to be mounted in a furnace wall having an opening therein comprising in combination, burner casing means having an air inlet adapted for receiving an inlet air flow, air induction chamber means having an outlet and mounted within said burner casing for receiving a predetermined portion of said inlet air flow and producing an uninterrupted helical vortex primary air flow from said outlet, refractory means including a substantially divergent surface extending outward from the periphery of said outlet to a plane common with the outer surface of said furnace wall, air gap means adapted to receive the remaining portion of said inlet air flow, said air gap means comprising at least one air gas of substantially uniform annular configuration extending through said refractory means and located between said outlet and the plane of said outer surface, means for imparting spinning directional motion to at least part of the remaining portion of said inlet air flow as it enters said one air gap, said one air gap being angularly disposed relative to the plane of said outer surface for projecting spinning secondary air flow in an outward direction relative to said outlet of said induction chamber for containment of the flame envelope, whereby intimate mixing of fuel and air is obtained proximate the point of fuel injectioN.