US3804578A

US3804578A - Cyclonic combustion burner

Info

Publication number: US3804578A
Application number: US00296308A
Authority: US
Inventors: D Robbins
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-10-10
Filing date: 1972-10-10
Publication date: 1974-04-16
Anticipated expiration: 1991-04-16

Abstract

A compact cyclonic burner having a tangential fuel input and peripheral secondary air inlets arranged in such a manner that the secondary air combines more readily with the liquid or gaseous burning fuel during the combustion process by aiding the vaporizing, distilling, gasifying and oxidizing of the burning fuel.

Description

United States Patent 1191 Robbins CYCLONIC COMBUSTION BURNER [76] Inventor: Donald D. Robbins, 3539 E. 1

I Piccadilly Rd., Phoenix, Ariz. 85018 22 Filed: 061. 10, 1972 21 Appl. No.2 296,308

[52] US. Cl. 431/158, 431/173, 431/351 [51] Int. Cl. F23! l/00 [58] Field of Search 431/173, 351, 353, 157,

[56] References Cited I UNITED STATES PATENTS 3,667,221 6/1972 Taylor 431/173 [-451 Apr. 16, 1974 3,437,085 4/1969 Perry 431/173 FOREIGN PATENTS OR APPLICATIONS 1,004,670 11/1951 France 431/173 Primary Examiner-Carroll B. Dority, Jr. Attorney, Agent, or Firm-Warren F. BLLindsley [5 7] ABSTRACT A compact cyclonic burner having a tangential fuel input and peripheral secondary air inlets arranged in such a manner that the secondary air combines more readily with the liquid or gaseous burning fuel during the combustion process by aiding the vaporizing, dis tilling, gasifying and oxidizing of the burning fuel.

' 5 Claims, 5 Drawing Figures PATENTED R 6mm 4 3.804.578

SHEH 1 OF 2 CYCLONIC COMBUSTION BURNER BACKGROUND OF THE INVENTION Heretofore burners for furnaces, boilers, water heaters and the like have been relatively complicated in construction and have employed numerous parts in their manufacture, which makes them subject to a lot of maintenance, and they require skilled craftsmen to install and adjust them in order to obtain a degree of efficiency in operation.

The preliminary requirement in using any form of fuel is its conversion into a gas in order that it may combine more readily with oxygen in the combustion process. In most fuels, the chief combustible elements are carbon (C) and hydrogen (H), which are present in a great variety of chemical combinations with varying physical characteristics. When these fuels are completely burned, the products of combustion contain only carbonic acid, namely carbon dioxide (CO and water (H O), with nitrogen (N) and some of the oxygen of the air supplied for combustion, all of which are incombustible. But'when the fuel is incompletely or partially burned, the products of combustion will also contain varying quantities of carbon monoxide (CO), various forms of hydrocarbon (C H hydrogen and sometimes tar and smoke as the products of distillation, all of which are combustible or have a heating value, which is wasted if not oxidized in the combustion process.

Fuel may be burned by eitherdirect firing on a grate or after conversion into gaseous form. The ultimate object of direct firing is the attainment of complete combustion in close proximity to the fuel bed by vaporizing, distilling, gasifying and completely burning the fuel within the same chamber. It is well known, however, that the processes of vaporization and distillation do not produce heat but, on the contrary, absorb it, and therefore it is advantageous to separate them from the point at which the combustion of the gases takes place and where high temperatures are developed by the heat evolved, as is accomplished by the use of a gas producer or generator.

In the gas producer or generator, the process of vaporization, distillatioriand gasification results in the generation of combustible gas, which is led away to a separate combustion chamber in which it is subsequently burned under conditions more favorable to a full realization of the heat value of the fuel.

FIELD OF THE INVENTION This invention relates to a simple, compactcyclonic burner employing a new and improved gas generator which is easy to install and adjust and which will provide a highly efficient burning of the fuel used. In addition, the present invention provides a burner which can be set at anyangle to direct the heat to any desired direction, that is, up, down, to either or both sides, and even at angles, should this be desired, without destroying the effectiveness of the gas generator. Also, the present invention is designed to burn gaseous and liquid fuels more efficiently to provide more heat more quickly with less BTU input than conventional burners by burning the normal products of incomplete combustion, since the burner operates at a higher temperature than heretofore possible.

DESCRIPTION OF THE PRIOR ART It is well known that present burners for furnaces, boilers, water heaters, and the like are complicated and touchy to install and adjust for efficient operation. The complicated construction of the burners results in a higher cost of manufacture, and therefore the selling price is relatively high. The complicated construction also makes these burners more expensive to maintain and to adjust, even though they can never by an efficient burner of fuels. At their best they still produce combustable carbon monoxide. Thus, it is desirable to produce a gas generator which will provide a timely and proper amount of secondary air so as to convert the carbon monoxide into incomb'ustable carbon dioxide, thereby obtaining complete combustion of the fuel used.

SUMMARY OF THE INVENTION In accordance with the invention claimed, the cyclonic burner disclosed embodies a gas generator of the simplest possible construction and can be manufactured at a relatively low cost but still obtain complete combustion of the burner fuel used. In addition, this invention provides a burner which will burn liquid or gaseous fuels at a higher temperature than the prior art burners, thereby burning the heretofore unburned combustible elements. I

It is, therefore, one object of this invention to provide a cyclonic burner for liquid and/ or gaseous fuels employing a new gas generator which is compact and of simple construction. i i

Another object of this invention is to provide a new and improved burner which effectively converts carbonaceous fuel into carbon monoxide gas and then burns it completely.

A further object of this invention is to provide a burner which, by means of secondary air introduced in a given manner, efficiently and cleanly burns the fuel at higher temperatures. 1 e

A still further object of this invention is to provide a burner which may be installed at any angle to direct heat in any one or more desired directions.

A still further object of this invention is to provide a .burner which may havemore than one fuel input associated therewith so that the burner may be utilized with more than one kind of fuel, whereby either or both fuels may be used in the burner as desired."

A still further object of this invention is to provide a simple, compact burner with tangentially disposed fuel inlets, thereby causing the fuel totraverse a cyclonic path during initial and final burning of the fuel.

A still further object of this invention is to provide a simple, compact burner which has a substantially circular burner housing to provide for the cylonic burning of fuels in conjunction with the tangential fuel input.

A still further object of this invention is to provide a plurality of secondary air inlets or slots around the periphery of the burner housing through which preheated secondary air will be drawn to aid in the burning of heavier fuel particles. l i

A still further object of this invention is to provide an interiorbaffle within the burner to control the movement of and direct burning fuel into the path of the incoming fuel-air mixture to ensure proper ignition and burning of the fuel.

A specific object of this invention is to provide a high speed cyclonic or rotary path of the burning fuels whereby the heavier particles of the fuel will be carried near the outside of the burning gases near the secondary air inlets so that secondary air will be drawn into the burner to implement the complete burning of the heavier fuel particles to provide the highest possible efficiency of fuel burning the BTU recovery, and minimize, if not preclude, the discharge of undesirable unburned fuels from the burner.

A further specific object of this invention is to provide a burner with a plurality of fuel inlets whereby low-fire and high-fire conditions may be easily attained, still maintaining efficient burner operation.

These and other objects and advantages of the present invention will become more apparent as the description proceeds, and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

BRIEF DESCRIPTION OF THE DRAWING The present invention may be more readily described by reference to the accompanying drawings, in which:

FIG. 1 is a perspective view, with parts broken away, of a cyclonic burner employing the invention.

FIG. 2 is'a sectional view on the line 2-2 of FIG. 1 but showing a venturi-type fuel-air input tube.

FIG. 3 is-a view similar to FIG. 1 but illustrating a burner with two fuel inputs, one a gaseous fuel input, and the other a liquid fuel input.

FIG. 4 is a horizontal sectional view of a modified form of my cyclonic burner which has a secondary air housing surrounding the burner housing to supply secondary air from an external source.

FIG. 5 is a perspective view of a modified form of my cyclonic burner, with parts broken away, showing more than one fuel-air inlet.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more particularly to the drawings by characters of reference, FIG. 1 and 2 illustrate a burner comprising a housing 1 substantially circular in shape and having two spaced

opposed sides

2 and 3, which for convenience in description will be called the top and bottom, respectively, of the burner. Although shown in a horizontal position, it is to be understood that the disposition of the burner may be at any desired angle or position to serve a particular need. The top and bottom of the burner are joined by substantially perpendicular side walls 4, which form the periphery of the burner.

Housing 1 is preferably fabricated from any suitable high heat resistant material, for example, stainless steel, or it may be made with a suitable material having a ceramic lining or coating.

A fuel and air intake 5 is connected to housing 1 and is disposed so as to provide a tangential extension of the side wall 4, as shown. The intake 5 preferably includes a tubular extension into which fuel, indicated by arrows 6-6, may be injected into housing 1 of the burner by fuel nozzle 7. The fuel injected into input 5 draws air with it into housing 1 through input 5 and the fuel and air then pass over an ignition device 8. The ignition device 8 is located within the burner housing adjacent intake 5. The fuel is ignited and caused to swirl around the inside of the housing as it burns in a cyclonic action.

As seen in the drawing, top 2 of the housing is provided with a circular perforated exhaust plate 9 axially mounted thereon to provide the exhaust or discharge of the burner. Heat from the burner will be concentrated and transmitted through exhaust plate 9 and may be directed in any suitable direction by suitably mounting the burner. Although exhaust plate 9 is shown and described, it should be noted that it may be omitted and the burner would function satisfactorily.

The cyclonicburning action and its centrifugal characteristics causes the heavier and larger fuel particles to be carried in suspension in the burning gases adjacent the periphery of the burner, that is, adjacent walls 4; while the smaller and lighter fuel particles tend to move toward the center of the cyclonic movement and are burned more readily and quickly.

To ensure complete burning of the larger, heavier fuel particles as they are swirled in the burner housing as well as maintaining the burning bases longer in the burning housing,.a gas generator is provided around the inside periphery of housing 12 which includes a plurality of secondary air inlets 1010 through the peripheral walls 4. Secondary air will be drawn into the burner housing through these air inlets by suction action created by the swirling burning gases in housing 1. This swirling action aids the combustion of the fuel carried adjacent the outer periphery of the burner housing by oxidizing the unburned gases. It is deemed apparent that the air drawn into the housing through the secondary air inlets will be preheated by the inherent heat of the housing while the burner is operating, and that this preheated air will assist the burning of the larger and heavier fuel particles, which as they burn will become lighter and therefore will move inwardly toward the center of the cyclonic burning gases and should be completely consumed by the time they are exhausted through the discharge 9. Since it is necessary to vaporize, distill, and gasify the fuel before complete combustion occurs, and since it is desirable to separate this action from the zone of complete combustion, the area around the inside periphery of the housing which is partly closed by

sides

2, 3 and 4 performs this function. It is, in fact, a generating area for the center of the burner and furnishes fuel to the centerof the cyclonic burner for burning without. the center of the burner being cooled by the vaporizing, distilling, gasification and oxidation action.

As may be more clearly seen in the sectional view of FIG. 4, the secondary air inlets 10-10 have a lip 11 which extends into the burner chamber 12 so that there is an overlap to create a pressure drop or suctionto aid in drawing or pulling of secondary air into the burner chamber, and to preclude any blow-back through the secondary air inlets.

OPERATION In the operation of the burner, shown in FIG. 1, liquid or gaseous fuel 6 such as propane gas is injected into the combustion or burner chamber 12 from nozzle 7 through the tubular air and fuel intake 5. The fuel injection process draws primary air into intake 5, as well known in the art, and air and fuel 6 enters the combustion chamber 12 after passing over the ingition device 8. Device 8 may be of any desired type, such as, for example, a spark device or pilot flame 13, as shown in FIG. 5. The fuel is ignited and starts to swirl around the inside of the periphery of chamber 12 in a zone identified as a gas generator in a cyclonic action to vaporize, distill and fully gasify thefuel and air so that the complete high temperature burning of the gases may occur in the center portion of the burner.

In FIG. 4 is shown an arcuate baffle or deflector plate 14 which is installed within the burner chamber in spaced relationship to the outer or peripheral walls 4, the arc of the plate corresponding to the arcuate shape of the adjacent walls whereby a narrow passage 15 is provided between the outer walls 4 and the center portion of the burning chamber 12. The baffle 14 serves to ensure that some of the burning gases of the cyclonic burning mixture are maintained adjacent the outer walls 4 in the gas generator portion of the burner until the gas is completely vaporized, distilled and gasified and directed across the tangential fuel inlet 5 so that the ignition of newly injected fuel is positively ensured.

MODIFICATIONS In FIG.2 a sectional view of the fuel inlet 5 is shown wherein opening.16 is of a venturi shape to assist in drawing air and fuel into the burner chamber.

In addition, FIG. 2 shows an auxiliary fuel supply line 17 mounted in the fuel intake 5, whereby a second fuel such as No. 2 fuel oil 18 may be introduced from a fuel source or supply not shown. The venturi action created by the venturi inlet 16 will draw the fuel, for example, fuel oil, into the burner chamber 12 for burning. It is deemed apparent that the propane fuel and/or the fuel oil can be burned either singly or together to obtain a desired result. All other parts of the burner are similar to those shown in FIG. 1 and given the same reference characters. Like parts in FIGS. 2-5 also have similar reference characters. 1

In FIG. 3 a dual fuel feed system is shown for the burner. One feed structure comprises the propane or gaseous fuel nozzle 7 heretofore described feeding into a fuel intake 5. Disposed at about 180? therefrom is a second fuel inlet 5A. The second fuel inlet SA has a fueloil injection nozzle 19 and an ignition device 8. Fuel intake 5 also has an ignition device, not shown. The two fuel inlets! and 5A may be used singly or together to meet fuel availability or heat requirements, and because the inlets are tangentially arranged relative toburner chamber 12, they will each provide for an assist in obtaining the cyclonic burning action. It should be recognized that both fuel inlets may discharge the same type of fuel.

FIG. 3 also shows a perforated exhaust or discharge plate 20 on the bottom 3 of the housing as well as the exhaust plate 9 on top 2 of the housing. This arrangement permits heat to bedirected in two directions from the burner to fulfill the special heating requirements. As mentioned above, the

plates

9 and 20 may be omitted, if so desired.

FIG. 4 shows a modified form of the invention which may be mounted in a closed-in area, such as a home furnace where secondary air may not be available, and where the secondary air to be drawn into the inlets 10 can be introduced to the burner by controlled means. 6

A secondary air duct or housing 22 is provided around the periphery of the burner to enclose the secondary air inlets 10, as shown. The fuel inlet tube 5B is enlarged to embrace the secondary air duct and this inlet tube carries the fuel nozzle 7 and ignition device 8. The secondary air duct is provided with fitting 23 to receive a connection from an outside source of forced air, not shown, to supply secondary air to the air duct 22 to be drawn into the burner in the manner previously described. A damper 24, or other suitable air control device, may be used to control the amount of secondary air going into the duct 22.

FIG. 5 shows a modified form of the invention wherein two fuel intakes 5C and 5D are employed, the inlets being relatively close to each other, as shown. The intake 5C is the primary fuel inlet and has an ignition device 8, such as a pilot light, spark igniter or the like. This form of the invention is well suited to burner applications where high-fire and low-fire conditions are called for. As can be readily seen, with only the primary fuel inlet in operation, a low-fire condition may be maintained. When high-fire is called for, fuel may be injected into intake 5D and will be: ignited immediately and join with the burning fuel from intake 5C and a hotter burn will be obtained for as long as fuel is injected through intake 5D.

Although the burner structures shown and described are fed from nozzles 7, it should be: recognized that it is intended to be within the scope of this invention to utilize any of the burners shown as after burners, i.e. burners for recycling the burning the exhausts of other combustion devices. In this instance, for example, the

burner structure of FIG. 2 may be used without nozzle It will be apparent to those skilled in the art that various changes and modifications may be made to the apparatus shown and described herein without departing from the spirit of the invention or from the scope of th appended claims.

What I claimis: 1. A cyclonic burner comprising: a substantially circular housing having a top and a bottom, wall means joining said top and bottom and maintaining same in spaced substantially parallel relationship and forming the periphery of said burner, said top having an open area to act as a burner discharge, 1 l said wall means having spaced secondary slotted air inlets arranged to extend between said top and bottom of said burner to inject air into said burner substantially tangentially to the wall of said housing along its inside periphery,

' said secondary air inlets comprise lips extending in the direction of cyclonic movement of the gases within said burner slightly past the slotted opening in the housing to create a pressure drop at said inlets to draw air into said burner and to prevent blow-back through said inlets,

fuel inlet means connected to said housing and disposed to inject fuel into said housing substantially tangentially to its inside wall,

and fuel ignition means within said burner adjacent said inlet means whereby the secondary air from said slotted air inlets and the primary air and fuel from said fuel inlet swirl around the inside periphery of said housing while burning to vaporize, distill and gasify the air and heavy fuel particles adjacent the inside wall of the said fuel inlet means comprises a venturi section therein to aid in drawing air into said burner. 4. The cyclonic'burner set forth in claim 1 wherein:

the center portion of either the top or bottom of the housing is provided with perforated sections for discharge of heated burner gases from said burner.

5. The cyclonic burner set forth in claim 1 in further combination with:

a secondary air duct coaxially mounted around said housing and enclosing said secondary air inlets, and means to introduce air into said secondary air duct for injection through said secondary air inlets.

Claims

1. A cyclonic burner comprising: a substantially circular housing having a top and a bottom, wall means joining said top and bottom and maintaining same in spaced substantially parallel relationship and forming the periphery of said burner, said top having an open area to act as a burner discharge, said wall means having spaced secondary slotted air inlets arranged to extend between said top and bottom of said burner to inject air into said burner substantially tangentially to the wall of said housing along its inside periphery, said secondary air inlets comprise lips extending in the direction of cyclonic movement of the gases within said burner slightly past the slotted opening in the housing to create a pressure drop at said inlets to draw air into said burner and to prevent blow-back through said inlets, fuel inlet means connected to said housing and disposed to inject fuel into said housing subStantially tangentially to its inside wall, and fuel ignition means within said burner adjacent said inlet means whereby the secondary air from said slotted air inlets and the primary air and fuel from said fuel inlet swirl around the inside periphery of said housing while burning to vaporize, distill and gasify the air and heavy fuel particles adjacent the inside wall of the housing before being propelled inwardly of the burner for complete combustion.

2. The cyclonic burner set forth in claim 1 in further combination with: a second fuel inlet means connected to said housing in spaced relationship to first said fuel inlet means to introduce additional fuel to said burner tangentially to the inside wall of said burner.

3. The cyclonic burner set forth in claim 1 wherein: said fuel inlet means comprises a venturi section therein to aid in drawing air into said burner.

4. The cyclonic burner set forth in claim 1 wherein: the center portion of either the top or bottom of the housing is provided with perforated sections for discharge of heated burner gases from said burner.

5. The cyclonic burner set forth in claim 1 in further combination with: a secondary air duct coaxially mounted around said housing and enclosing said secondary air inlets, and means to introduce air into said secondary air duct for injection through said secondary air inlets.