CA2859522A1 - Burner system - Google Patents

Abstract

A burner system has an outlet area, an air flow passageway and a fuel flow passageway. The air flow outlet and the fuel flow outlet are disposed adjacent the outlet area. A
source of air flow is connected to the air flow passageway to deliver fuel to the fuel flow passageway at a gauge pressure of greater than zero p.s.i. and less than ten p.s.i. A
source of gaseous fuel flow is connected to the fuel flow passageway to deliver air to the air flow passageway at a gauge pressure of greater than zero p.s.i. and less than twenty p.s.i. The source of air flow delivers air to the air flow passageway at a gauge pressure less than the gauge pressure that the source of gaseous fuel flow delivers fuel to the fuel flow passageway.

Description

BURNER SYSTEM
RELATED APPLICATIONS
[0001] This application is a non-provisional application claiming priority from U.S. Provisional Patent Application Serial No. 61/940,790 filed on February 17, 2014.
FIELD OF THE INVENTION

[0002] The present invention relates to burners, and more particularly to burners that mix air or oxygen with a gaseous fuel.
BACKGROUND OF THE INVENTION

[0003]
Burners that use gaseous fuel are used in many applications including boilers, line heaters, furnaces, other gas-fired appliances, and in many others.
Basically, these burners direct a stream of gaseous fuel and a stream of air or oxygen typically from a nozzle into a in a combustion chamber or the like, such that the stream of gaseous fuel and a stream of air are generally combined one with the other into a blended flow. The resulting blended flow of fuel and air or oxygen is ignited and exits the burner either as a visible flame or as a stream of an extremely hot gaseous mixture.

[0004] In an attempt to improve the state of the art for burners used in various applications, the present inventor developed a new burner with several significantly improved aspects. This burner is taught in United States Published Patent Applications 12/564,319, 12/564,337, and 12/564,369, which are incorporated herein by reference.

[0005] While the burner and the various associated components disclosed in these published patent applications work very well and present a significant advancement in the art, it has since been realized that there are some improvements that could be made to their initial designs. For instance, initially, the burners constructed in accordance with the teachings of these published patent applications used an air compressor as a source of air flow, with the air compressor producing a stream of compressed air flow at a pressure of about seventy-five (75) PSI. At the time, it was fully believed that with the overall structure of the burner, it was necessary to use a source of compressed air flow at this pressure. This was especially thought to be true if the burner was to achieve combustion of acceptable quality, especially if the burner is to fully combust the fuel being fed into it and produce a very low emission output.
Indeed, most industrial burners of significant size do use a stream of compressed air flow in this pressure range.

[0006]
Further, it was realized that using an air compressor as a source of compressed air flow is not cost effective, but instead is prohibitively expensive, even to a point where the cost of the overall burner system would preclude entry into some markets.

[0007] Since that time, quite unexpectedly, it has been found that it is indeed possible to use a source of air flow at significantly lower pressures.
Initially, it was believed that this would result in incomplete combustion, or even combustion of unacceptably poor quality, and that there would be little hope of achieving combustion where no NOx was present.

[0008]
United States Patent No. 3,822,985 issued July 9, 1974 to Straitz III, discloses a flare stack gas burner for waste combustible gases that operates at both low and high pressure and under all flow conditions including low pressure gas without any high pressure gas stream from oil refineries. There are separate delivery systems for the combustion gases. A
stack with a central low pressure gas delivery tube has, at its top, outwardly extending vanes with gas delivery slots. The vanes are disposed for imparting a swirling action to the burning gas.
The delivery pipe is closed at the top by a closure plate with flame retention openings. Air at variable low pressure is delivered into the stack at the bottom and flows upwardly between the vanes for smokeless burning. A pipe is provided for high pressure gas mounted exteriorly of the stack for delivery to a manifold ring and thence to delivery pipes with angularly disposed tips for enhancement of the burning of the gases. An optional fluidic seal can be provided in the low pressure gas supply.
Ignitors and pilots are provided exteriorly of the stack. This burner does not teach having the pressure of the air flow the pressure of the gaseous fuel flow in order to achieve combustion of acceptable quality, and also does not teach having substantially only low pressure gas flow.

[0009] United States Published Patent Application No.
2007/000102 published January 4, 2007, to Kjeldal et al., discloses a nozzle for air-assisted atomizing of a liquid fuel.
The nozzle comprises a fuel feed passage, an air feed passage, and a swirling chamber from which fuel and air may be passed to an exit orifice for emerging a cone shaped spray. An air bypass passage is provided for leading a fraction of the air flow in the air feed passage past the swirling chamber and to an air exit. The air exit is arranged such with respect to the exit orifice that, during operation of the nozzle, air emerging through the air exit reduces depositing of residues of fuel on a downstream surface of the nozzle element. Grooves or other flow-guiding elements may confer swirling or rotation of air in or downstream of the air feed passage and/or the air bypass passage. The invention may be applied throughout a wide interval of fuel and air flow rates and pressures. A particular relevant field of usage is the low-pressure field, in which pressurized fluid fuel and pressurized air enter the nozzle at a relatively low operating pressure, e.g. 0.01-0.5 bar. This burner does not teach having the pressure of the air flow the pressure of the gaseous fuel flow in order to achieve combustion of acceptable quality.

[00010] United States Patent No. 3,824,073 issued July 16, 1974 to Straitz III, discloses a flare stack gas burner for waste combustible gases at both low and high pressure from oil refineries. There are separate delivery systems for the combustion gases, which includes a stack with a top mounted burner tip. The stack carries a centrally disposed high pressure gas supply pipe closed at the top and with a plurality of outwardly extending vanes with gas delivery slots. The tops of the vanes are angularly disposed in a plane with respect to radial lines through the center of the stack for a swirling action of the burning gas. A low pressure gas supply pipe is mounted to and extends upwardly along the outside of the stack to a ring manifold mounted to the burner tip with a plurality of inwardly extending vanes, with gas delivery slots. The inwardly extending vanes are interposed between the outwardly extending vanes and are angularly disposed in the same direction. Air at variable controlled low pressure is delivered into the stack at the bottom and moves upwardly between the vanes for smokeless burning. Optional fluidic seals can be provided in both the low and high pressure gas supply lines to prevent flashback.
Ignitors and pilots are provided exteriorly of the stack. This burner does not teach having the pressure of the air flow the pressure of the gaseous fuel flow in order to achieve combustion of acceptable quality, and also does not teach having substantially only low pressure gas flow.

[00011] United States Patent No. 3,824,073 issued July 16, 1974 to Straitz III, discloses an air-cooled oxygen-gas burner for use with a direct fired furnace. The burner comprises a body formed from three concentric metal tubes supported in a cylindrical housing secured about a conical bore in a refractory side wall of a furnace. The three concentric tubes have a cone shaped inner end, which are adjustable to define a nozzle with annular openings therebetween. The openings are of variable size to vary the shape of a flame produced by a mixture of combustible gas, oxygen and air fed under pressure, respectively, in each of two chambers defined between the three concentric metal tubes and a chamber defined between the tubes and the cylinder housing. The combustible gas is fed in the inner chamber, the oxygen in the intermediate chamber, while the air is fed in the outer chamber to cool the concentric tube assembly and the furnace refractory about the burner nozzle.
This burner does not teach having the pressure of the air flow the pressure of the gaseous fuel flow in order to achieve combustion of acceptable quality.

[00012] It is an object of the present invention to provide a burner system that uses low air pressure and low fuel pressure.

[00013] It is an object of the present invention to provide a burner system that uses substantially only low pressure gas flow.

[00014] It is an object of the present invention to provide a burner system that uses substantially only low pressure air flow.

[00015] It is an object of the present invention to provide a burner system that uses low air pressure and low fuel pressure, and wherein the gas pressure is lower than the air pressure.

[00016] It is a further object of the present invention to provide a burner system, wherein the source of gaseous fuel flow delivers fuel at a pressure of between about zero (0) p.s.i. and about ten (10) p.s.i.

[00017] It is a further object of the present invention to provide a burner system, wherein the source of air flow delivers air at a pressure of between about zero (0) p.s.i. and about fifty (50) p.s.i.

[00018] It is an object of the present invention to provide a burner system that burns fuel very efficiently.

[00019] It is another object of the present invention to provide a burner system that produces minimal unwanted emissions.

[00020] It is another object of the present invention to provide a burner system that achieves combustion where no NOx is present.

[00021] It is a further object of the present invention to provide a burner system that can be used with various types of gaseous fuels.

[00022] It is a further object of the present invention to provide a burner system that is cost effective.

SUMMARY OF THE INVENTION

[00023] In accordance with one aspect of the present invention there is disclosed a novel burner system comprising a main body having an outlet area, an air flow passageway with an air flow inlet and an air flow outlet and a fuel flow passageway with a fuel flow inlet and a fuel flow outlet. The air flow outlet and the fuel flow outlet are disposed adjacent the outlet area of the main body, to thereby permit delivery of air from the air flow outlet and delivery of fuel from the fuel flow outlet each to a destination for subsequent combustion. A
source of air flow is connected in air delivery relation to the air flow inlet of the air flow passageway. A
source of gaseous fuel flow is connected in fuel delivery relation to the fuel flow inlet of the fuel flow passageway. The source of gaseous fuel flow delivers fuel to the fuel flow inlet of the fuel flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than ten (10) p.s.i. The source of air flow delivers air to the air flow inlet of the air flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than fifty (50) p.s.i.
The source of air flow delivers air to the air flow inlet of the air flow passageway at a gauge pressure less than the pressure at which the source of gaseous fuel flow delivers fuel to the fuel flow inlet of the fuel flow passageway.

[00024] In accordance with another aspect of the present invention there is disclosed a novel burner system comprising an assembly having an outlet area, an air flow passageway with an air flow inlet and an air flow outlet and a fuel flow passageway with a fuel flow inlet and a fuel flow outlet. The air flow outlet and the fuel flow outlet are disposed adjacent the outlet area of the assembly, to thereby permit delivery of air from the air flow outlet and delivery of fuel from the fuel flow outlet each to a destination for subsequent combustion. A
source of air flow is connected in air delivery relation to the air flow inlet of the air flow passageway. A source of gaseous fuel flow connected in fuel delivery relation to the fuel flow inlet of the fuel flow passageway. The source of gaseous fuel flow delivers fuel to the fuel flow inlet of the fuel flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than ten (10) p.s.i. The source of air flow delivers air to the air flow inlet of the air flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than fifty (50) p.s.i.
The source of air flow delivers air to the air flow inlet of the air flow passageway at a gauge pressure less than the pressure at which the source of gaseous fuel flow delivers fuel to the fuel flow inlet of the fuel flow passageway.

[00025] In accordance with another aspect of the present invention there is disclosed a novel burner system comprising an air flow delivery apparatus having an air flow passageway with an air flow inlet and an air flow outlet. A fuel flow delivery apparatus has a fuel flow passageway with a fuel flow inlet and a fuel flow outlet. The air flow outlet and the fuel flow outlet are disposed to permit delivery of air from the air flow outlet and delivery of fuel from the fuel flow outlet each to a destination for subsequent combustion. A source of air flow connected in air delivery relation to the air flow inlet of the air flow passageway. A source of gaseous fuel flow connected in fuel delivery relation to the fuel flow inlet of the fuel flow passageway. The source of gaseous fuel flow delivers fuel to the fuel flow inlet of the fuel flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than ten (10) p.s.i. The source of air flow delivers air to the air flow inlet of the air flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than fifty (50) p.s.i. The source of air flow delivers air to the air flow inlet of the air flow passageway at a gauge pressure less than the pressure at which the source of gaseous fuel flow delivers fuel to the fuel flow inlet of the fuel flow passageway.

[00026] In accordance with another aspect of the present invention there is disclosed a novel method of combustion comprising the steps of delivering air from a source of air flow to an air flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than fifty (50) p.s.i.; delivering fuel from a source of fuel flow to a fuel flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than ten (10) p.s.i.; delivering air from an air flow outlet of the air flow passageway and fuel from a fuel flow outlet of the fuel flow passageway each to a destination for subsequent combustion;
wherein the source of air flow delivers air to the air flow inlet of the air flow passageway at a gauge pressure less than the gauge pressure at which the source of gaseous fuel flow delivers fuel to the fuel flow inlet of the fuel flow passageway.

[00027] Other advantages, features and characteristics of the present invention, as well as methods of operation and functions of the related elements of the structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description and the appended claims with reference to the accompanying drawings, the latter of which is briefly described herein below.
BRIEF DESCRIPTION OF THE DRAWINGS

[00028] The novel features which are believed to be characteristic of the burner system according to the present invention, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following drawings in which a presently illustrated embodiment of the invention will now be illustrated by way of example. It is expressly understood, however, that the drawings are for the purpose of illustration and description only, and are not intended as a definition of the limits of the invention. In the accompanying drawings:

[00029] Figure 1 is a right side elevational view of the illustrated embodiment of the burner system according to the present invention;

[00030] Figure 2 is a front end view of the first illustrated embodiment of the burner system of Figure 1;

[00031] Figure 3 is a back end view of the first illustrated embodiment of the burner system of Figure 1; and, [00032] Figure 4 is a sectional view of the first illustrated embodiment of the burner system of Figure 1, taken along section line 4-4 of Figure 1.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT

[00033] Reference will now be made to Figures 1 through 4, which show an illustrated embodiment of the burner system according to the present invention, as indicated by general reference numeral 100.

[00034] In brief, the illustrated embodiment of the burner system 100 comprises a main body 110 having a back end 111 and a front end 112 and comprising a rear housing 120, a central housing 130, a front housing 140, an air flow passageway 150 and a fuel flow passageway 160, and a combustion chamber housing 170 having a narrower rearward combustion chamber housing 180 and a wider forward combustion chamber housing 190.

[00035] More specifically, the illustrated embodiment of the burner system 100 comprises the main body 110 having an outlet area 112, an air flow passageway 150 with an air flow inlet 151 and an air flow outlet 152, and a fuel flow passageway 160 with a fuel flow inlet 161 and a fuel flow outlet 162. The air flow inlet 151 actually comprises a first air flow inlet 151a and a second air flow inlet 151b. The air flow outlet 152 and the fuel flow outlet 162 are disposed adjacent the outlet area 112 of the main body 110, to thereby permit delivery of air from the air flow outlet 152 and delivery of fuel from the fuel flow outlet 162 each to a destination for subsequent combustion 114.

[00036] As can be best seen in Figure 4, the main body 110 comprises the rear housing 120, the central housing 130, the front housing 140, and a fuel nozzle 200 disposed within and generally surrounded by the rear housing 120, the central housing 130, and the front housing 140.

[00037] A
source of air flow 104 is connected in air delivery relation to the air flow inlet 151 of the air flow passageway 150. More specifically, the source of air flow 104 is connected in air delivery relation to the first air flow inlet 151a via a first connecting hose 153a and is connected in air delivery relation to the second air flow inlet 151b via a second connecting hose 153b. It should be noted that in the illustrated embodiment, the source of air flow 104 is the only source of air flow.
Alternatively, the source of air flow 104 could be the primary source of air flow along with a secondary source of air flow at a suitable pressure.
Further, a source of gaseous fuel flow 106 is connected in fuel delivery relation to the fuel flow inlet 161 of the fuel flow passageway 160 via a connecting hose 163. It should be noted that in the illustrated embodiment, the source of gaseous fuel flow 106 is the only source of fuel flow. Alternatively, the source of fuel flow could be the primary source of fuel flow along with a secondary source of fuel flow at a suitable pressure.

[00038] The burner system 100 further comprises an air flow disruption apparatus 220 disposed in operative relation in conjunction with the air flow passageway 150, to thereby create a turbulent flow of air in the air flow passageway 150. The air-flow disruption apparatus 220 comprises in seriatim and in fluid communication one with the next, the first air flow inlet 151, a substantially annular intake air flow chamber 222, an air flow opening 224, a substantially annular turbulent air flow chamber 230, and an air transfer egress 232. In another aspect, the air flow disruption apparatus 220 comprises a perforated wall 226, and a portion of the air flow passageway 150 comprises the substantially annular intake air flow chamber 222, the air flow opening 224 in the perforated wall 226, and the substantially annular turbulent air flow chamber 230 connected in fluid communication and in seriatim one with the other.

[00039] As can be best seen in Figure 4 of this illustrated embodiment, the air flow passageway 150 comprises the air flow inlet 151 in the form of a first air flow inlet 151a and a second air flow inlet 151b, the intake air flow chamber 222, the air flow opening 224 in the form of a first air flow opening 224a and a second air flow opening 224b (the third and fourth air flow openings cannot be seen in the drawings), the turbulent air flow chamber 230, and the air transfer egress 232, at least one air flow channel 240 and a corresponding number of air flow outlets 152, all in fluid communication and in seriatim one with the next.

[00040] As can be readily seen in Figure 4, a portion of the air flow passageway 150 disposed immediately rearwardly of the combustion chamber housing 170 comprises a first air flow channel 240a on the fuel nozzle 200, and more specifically comprises five substantially parallel air flow channels, namely a first air flow channel 240a, a second air flow channel 240b, a third air flow channel 240c, a fourth air flow channel 240d, and a fifth air flow channel 240e. The first, second, third, fourth, and fifth air flow channels 240a-e are in fluid communication and in seriatim with the air flow inlet 151, the intake air flow chamber 222, the first air flow opening 224, the turbulent air flow chamber 230, and the air transfer egress 232.
Further, the first air flow channel 240a, the second air flow channel 240b, the third air flow channel 240c, the fourth air flow channel 240d, and the fifth air flow channel 240e terminate in a first air flow outlet 152a, a second air flow outlet 152b, a third air flow outlet 152c, a fourth air flow outlet 152d, and a fifth air flow outlet 152e, respectively, which together form the overall air flow outlet 152 of the air flow passageway 150.

[00041] The first air flow channel 240a, the second air flow channel 240b, the third air flow channel 240c, the fourth air flow channel 240d, and the fifth air flow channel 240e are each helically shaped and are each disposed in substantially parallel relation on the fuel nozzle 200. As can readily be seen, due to the helical shape of the five air flow channels 240, the portion of the air flow passageway 150 at the outlet area 112, which includes the air flow outlet 152, is oriented obliquely, as will be discussed in greater detail subsequently.

[00042] It has been found that it is preferable to have this number of air flow channels 240 for the purpose of even air flow and distribution. Any suitable number of air flow channels 240 could be used depending on the specific application of the burner system 100, the size of the burner system 100 and the fuel nozzle 200, and so on. It has been found that each specific number of air flow channels 240 might have its own advantages and disadvantages.

[00043] As can be best seen in Figure 4, in the illustrated embodiment of the present invention, the fuel nozzle 200 is substantially straight and extends between a back end 201 and a front end 202. The fuel flow passageway 160 extends from its fuel flow inlet 161 at the back end 201 of the fuel nozzle 200 to the fuel flow outlet 162 at the front end 202 of the fuel nozzle 200, and is substantially straight except for the forward portion at the front end 202 of the fuel nozzle 200 where the fuel flow passageway 160 furcates into six separate passageways 200a-f each having its own fuel flow outlet 162a-f.

[00044] The combustion chamber housing 170, which is best seen in Figure 4, is preferably elongate and defines a generally central longitudinal axis "L", extends between a back end 171 and a front end 172, defines a combustion chamber 174, and comprises a narrower rearward combustion chamber housing 180 with a back and 181 and a front end 182, and a wider forward combustion chamber housing 190 with a back and 191 and a front end 192. The combustion chamber housing 170 is connected at its back end 171 to the main body 110 of the burner system 100 at the outlet area 112 such that the destination for subsequent combustion 114 is at or adjacent the outlet area 112 and is disposed within the combustion chamber 174.

[00045] The combustion chamber 174 has a narrower rearward chamber portion 184 and a wider forward chamber portion 194, and a hot air outlet 176 disposed at the front end 192 of the wider forward chamber portion 194.

[00046] The narrower rearward combustion chamber housing 180 generally defines the narrower rearward chamber portion 184 and the wider forward combustion chamber housing 190 defines the wider forward chamber portion 194.

[00047] In the illustrated embodiment, the narrower rearward combustion chamber housing 180 comprises a forwardly extending portion of the front housing 140 of the main body 110 and has an air and fuel ingress 185 and a combustion egress 186. The section of the narrower rearward chamber portion 184 immediately forward of the air and fuel ingress 185 is where the air from the five air flow outlets 152a-e and the fuel from the six fuel flow outlets 162 (a-f) combine together one with the other and combust. As is well known in the art, a flame or spark, or the like, is initially used to start the combustion of the fuel and air. Subsequently, the heat from the combustion of the fuel and air is sufficient to keep the combustion ongoing.

[00048] A
protective rearward insulative cover 188 is securely attached by means of welding in surrounding relation over the narrower rearward combustion chamber housing 180 by two annular end flanges 189, which are themselves securely attached by means of welding to the narrower rearward combustion chamber housing 180.
Alternatively, any other suitable means of attachment could be used. The narrower rearward combustion chamber housing 180, the protective rearward insulative cover 188 and the two annular end flanges 189 are made from a suitable heat resistant material.

[00049] An annular flange 187 is welded to the protective rearward insulative cover 188 to extend perpendicularly outward therefrom, to receive the wider forward combustion chamber housing 190 in secure relation thereon.

[00050] Similarly, the wider forward combustion chamber housing 190 comprises a forwardly extending tube and has a combustion ingress 195 and the hot air outlet 176.

[00051] A
protective forward insulative cover 198 is securely attached by means of welding in surrounding relation over the wider forward combustion chamber housing 190 by an annular end flange 199 and a back end plate 197. The annular end flange 199 and a back end plate 197 are themselves securely attached by means of welding to the wider forward combustion chamber housing 190.
Alternatively, any other suitable means of attachment could be used.
Together, the protective forward insulative cover 198, the protective forward insulative cover 198, the back end plate 197 and the annular end flange 199 form a front assembly 195 that is mounted onto the annular flange 187 by means of threaded fasteners (not shown). The protective forward insulative cover 198, the protective forward insulative cover 198, the back end plate 197 and the annular end flange 199 are made from a suitable heat resistant material.

[00052] It should also be noted that the five air flow outlets 152a-e are aimed into the combustion chamber 174 in an oblique direction with respect to the longitudinal axis "L" of the combustion chamber 174, to thereby deliver the flow of air from the air flow passageway 150 into the air and fuel ingress 185 of said combustion chamber 170, thereby inducing at least a peripheral flow of air in the combustion chamber 170.

[00053] After a significant amount of experimentation over a considerable amount of time, it has unexpectedly been found that the present invention, namely the burner system 100, operates fully and properly, and with complete combustion including no discernable or measureable NOx emissions, using a source of gaseous fuel flow 106 that delivers fuel to the fuel flow inlet 161 of the fuel flow passageway 160 at a very low gauge pressure, and a source of air flow 104 that delivers air to the air flow inlet 151 of the air flow passageway 150 at a very low gauge pressure.
Further, it has unexpectedly been found that complete combustion including no discernable or measureable NOx emissions, can be achieved using a source of air flow 104 that delivers air to the air flow inlet 151 of the air flow passageway 150 at a gauge pressure less than the pressure at which the source of gaseous fuel flow 106 delivers fuel to the fuel flow inlet 161 of the fuel flow passageway 160, which is not taught in the known prior art.

[00054] In the illustrated embodiment of the present invention, the source of gaseous fuel flow 106 delivers fuel to the fuel flow inlet 161 of the fuel flow passageway 160 at a gauge pressure of greater than zero (0) p.s.i. and less than ten (10) p.s.i.
Preferably the source of gaseous fuel flow 106 delivers fuel to the fuel flow inlet 161 of the fuel flow passageway 160 at a gauge pressure of greater than zero (0) p.s.i. and less than five (5) p.s.i., and even more preferably, the source of gaseous fuel flow 106 delivers fuel to the fuel flow inlet 161 of the fuel flow passageway 160 at a gauge pressure of two (2) p.s.i. and less than five (5) p.s.i.

[00055]
Further, the source of air flow 104 delivers air to the air flow inlet 151 of the air flow passageway 150 at a gauge pressure of greater than zero (0) p.s.i. and less than fifty (50) p.s.i. Preferably, the source of air flow 104 delivers air to the air flow inlet 151 of the air flow passageway 150 at a gauge pressure of greater than zero (0) p.s.i. and less than twenty (20) p.s.i. or at a gauge pressure of greater than ten (10) p.s.i. and less than fifty (50) p.s.i. Even more preferably, the source of air flow 104 delivers air to the air flow inlet 151 of the air flow passageway 150 at a gauge pressure of greater than ten (10) p.s.i. and less than twenty (20) p.s.i.

[00056]
Further, the ratio of oxygen in the source of air flow 104 to fuel in the source of gaseous fuel flow 106 is 11:1 and less than 16:1, and is 12.5:1 and less than 14.5:1. It has been found that if the molecular ratio of oxygen in the source of air flow to fuel in the source of gaseous fuel flow is about 13.5:1, excellent results re produced. This ratio of oxygen in the source of air to fuel provides a enough extra oxygen above a stoichiometric ratio to reduce the thermally produced NOx without extinguishing the combustion.

[00057] Even further, the ratio of the fuel flow gauge pressure to the fuel flow per hour is between about 1:1000 and about 1:3000, and preferably is between about 1:1500 and about 1:2500. It has been found that if the ratio of the fuel flow gauge pressure to the fuel flow per hour is about 1:2000, excellent results are produced.

[00058] Also, the ratio of the air flow gauge pressure to the air flow per hour is greater then zero 0:250 and less than 50:250, and preferably is greater then zero 0:250and less than 20:250. It has been found that if the ratio of the air flow gauge pressure to the air flow per hour is about 15:250, excellent results are produced.

[00059] In another aspect, the burner system 100 comprises an assembly 108 having the outlet area 112, the air flow passageway 150 with the air flow inlet 151 and the air flow outlet 152 and a fuel flow passageway 160 with a fuel flow inlet 161 and a fuel flow outlet 162. The air flow outlet 152 and the fuel flow outlet 162 are disposed adjacent the outlet area 112 of the assembly 108, to thereby permit delivery of air from the air flow outlet 152 and delivery of fuel from the fuel flow outlet 162 each to the destination for subsequent combustion 114. The other relevant components of this aspect of the present . invention are essentially the same as those described above with reference to the drawings, including reference numerals, and will not be discussed again for the sake of brevity.

[00060] In yet another aspect, the burner system 100 comprises an air flow delivery apparatus 109a with the air flow passageway 150 with the air flow inlet 151 and the air flow outlet 152, and a fuel flow delivery apparatus 109b with the fuel flow passageway 160 with the fuel flow inlet 161 and the fuel flow outlet 162. The other relevant components of this aspect of the present invention are essentially the same as those described above with reference to the drawings, including reference numerals, and will not be discussed again for the sake of brevity.

[00061] As can be understood from the above description and from the accompanying drawings, the present invention provides a a burner system that uses low air pressure and low fuel pressure, that uses substantially only low pressure gas flow, that uses substantially only low pressure air flow, that uses low air pressure and low fuel pressure, and wherein the gas pressure is lower than the air pressure, wherein the source of gaseous fuel flow delivers fuel at a pressure of between about zero (0) p.s.i. and about ten (10) p.s.i., wherein the source of air flow delivers air at a pressure of between about zero (0) p.s.i. and about fifty (50) p.s.i., that burns fuel very efficiently, that produces minimal unwanted emissions, that achieves combustion where no NOx is present, that can be used with various types of gaseous fuels, and that is cost effective, all of which features are unknown in the prior art.

[00062] Other variations of the above principles will be apparent to those who are knowledgeable in the field of the invention, and such variations are considered to be within the scope of the present invention.
Further, other modifications and alterations may be used in the design and manufacture of the fuel nozzle of the present invention without departing from the spirit and scope of the accompanying claims.

Claims (21)

1. A burner system comprising:
a main body having an outlet area, an air flow passageway with an air flow inlet and an air flow outlet and a fuel flow passageway with a fuel flow inlet and a fuel flow outlet;
wherein said air flow outlet and said fuel flow outlet are disposed adjacent said outlet area of said main body, to thereby permit delivery of air from said air flow outlet and delivery of fuel from said fuel flow outlet each to a destination for subsequent combustion;
a source of air flow connected in air delivery relation to said air flow inlet of said air flow passageway;
a source of gaseous fuel flow connected in fuel delivery relation to said fuel flow inlet of said fuel flow passageway;

wherein said source of gaseous fuel flow delivers fuel to said fuel flow inlet of said fuel flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than ten (10) p.s.i.;
wherein said source of air flow delivers air to said air flow inlet of said air flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than fifty (50) p.s.i.;
and, wherein said source of air flow delivers air to said air flow inlet of said air flow passageway at a gauge pressure less than the gauge pressure at which said source of gaseous fuel flow delivers fuel to said fuel flow inlet of said fuel flow passageway.

2. The burner system of Claim 1, wherein said source of gaseous fuel flow delivers fuel to said fuel flow inlet of said fuel flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than five (5) p.s.i.

3. The burner system of Claim 1, wherein said source of gaseous fuel flow delivers fuel to said fuel flow inlet of said fuel flow passageway at a gauge pressure of two (2) p.s.i. and less than five (5) p.s.i.

4. The burner system of Claim 1, wherein said source of air flow delivers air to said air flow inlet of said air flow passageway at a gauge pressure of greater than ten (10) p.s.i.
and less than fifty (50) p.s.i.

5. The burner system of Claim 1, wherein said source of air flow delivers air to said air flow inlet of said air flow passageway at a gauge pressure of greater than zero (0) p.s.i.
and less than twenty (20) p.s.i.

6. The burner system of Claim 1, wherein said source of air flow delivers air to said air flow inlet of said air flow passageway at a gauge pressure of greater than ten (10) p.s.i.
and less than twenty (20) p.s.i.

7. The burner system of Claim 1, wherein the molecular ratio of oxygen in said source of air flow to fuel in said source of gaseous fuel flow is 11:1 and less than 16:1.

8. The burner system of Claim 7, wherein the molecular ratio of oxygen in said source of air flow to fuel in said source of gaseous fuel flow is 12.5:1 and less than 14.5:1.

9. The burner system of Claim 1, further comprising an air flow disruption apparatus disposed in operative relation in conjunction with said air flow passageway, to thereby create a turbulent flow of air in said air flow passageway.

10. The burner system of Claim 9, wherein said air-flow disruption apparatus comprises in seriatim and in fluid communication one with the next, said air flow inlet, an intake air flow chamber, a first air flow opening, a turbulent air flow chamber, and an air transfer egress.

11. The burner system of Claim 1, wherein said air flow disruption apparatus comprises a perforated wall, and a portion of said air flow passageway comprises an intake air flow chamber, a first air flow opening in said perforated wall, and a turbulent air flow chamber connected in fluid communication and in seriatim one with the other.

12. The burner system of Claim 1, wherein a portion of said air flow passageway disposed immediately rearwardly of said combustion chamber comprises a first air flow channel on a fuel nozzle.

13. The burner system of Claim 1, further comprising a combustion chamber housing defining a combustion chamber having a hot air outlet, and wherein said combustion chamber housing is connected to said main body at said outlet area such that said destination is disposed within said burner system.

14. The burner system of Claim 1, wherein the portion of said air flow passageway at said outlet area, which includes said air flow outlet, is oriented obliquely to said longitudinal axis.

15. The burner system of Claim 1, wherein the ratio of the fuel flow gauge pressure to the fuel flow per hour is between about 1:1000 and about 1:3000.

16. The burner system of Claim 15, wherein the ratio of the fuel flow gauge pressure to the fuel flow per hour is between about 1:1500 and about 1:2500.

17. The burner system of Claim 1, wherein the ratio of the air flow gauge pressure to the air flow per hour is greater then zero 0:250and less than 50:250.

18. The burner system of Claim 17, wherein the ratio of the air flow gauge pressure to the air flow per hour is greater then zero 0:250and less than 20:250.

19. A burner system comprising:
an assembly having an outlet area, an air flow passageway with an air flow inlet and an air flow outlet and a fuel flow passageway with a fuel flow inlet and a fuel flow outlet;
wherein said air flow outlet and said fuel flow outlet are disposed adjacent said outlet area of said assembly, to thereby permit delivery of air from said air flow outlet and delivery of fuel from said fuel flow outlet each to a destination for subsequent combustion;

a source of air flow connected in air delivery relation to said air flow inlet of said air flow passageway;
a source of gaseous fuel flow connected in fuel delivery relation to said fuel flow inlet of said fuel flow passageway;
wherein said source of gaseous fuel flow delivers fuel to said fuel flow inlet of said fuel flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than ten (10) p.s.i.;
wherein said source of air flow delivers air to said air flow inlet of said air flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than fifty (50) p.s.i.;
and, wherein said source of air flow delivers air to said air flow inlet of said air flow passageway at a gauge pressure less than the gauge pressure at which said source of gaseous fuel flow delivers fuel to said fuel flow inlet of said fuel flow passageway.

20. A burner system comprising:
an air flow delivery apparatus having an air flow passageway with an air flow inlet and an air flow outlet;
a fuel flow delivery apparatus having a fuel flow passageway with a fuel flow inlet and a fuel flow outlet;
wherein said air flow outlet and said fuel flow outlet are disposed to permit delivery of air from said air flow outlet and delivery of fuel from said fuel flow outlet each to a destination for subsequent combustion;
a source of air flow connected in air delivery relation to said air flow inlet of said air flow passageway;
a source of gaseous fuel flow connected in fuel delivery relation to said fuel flow inlet of said fuel flow passageway;
wherein said source of gaseous fuel flow delivers fuel to said fuel flow inlet of said fuel flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than ten (10) p.s.i.;
wherein said source of air flow delivers air to said air flow inlet of said air flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than fifty (50) p.s.i.;
and, wherein said source of air flow delivers air to said air flow inlet of said air flow passageway at a gauge pressure less than the gauge pressure at which said source of gaseous fuel flow delivers fuel to said fuel flow inlet of said fuel flow passageway.

21. A method of combustion comprising the steps of:
delivering air from a source of air flow to an air flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than fifty (50) p.s.i.;
delivering fuel from a source of fuel flow to a fuel flow passageway at a gauge pressure of greater than zero (0) p.s.i. and less than ten (10) p.s.i.;

delivering air from an air flow outlet of the air flow passageway and fuel from a fuel flow outlet of the fuel flow passageway each to a destination for subsequent combustion;
wherein the source of air flow delivers air to the air flow inlet of the air flow passageway at a gauge pressure less than the gauge pressure at which the source of gaseous fuel flow delivers fuel to the fuel flow inlet of the fuel flow passageway.