FI20225319A1 - Burner, and combination of boiler-burner - Google Patents

Abstract

The invention relates to a burner (1) that can be installed in a boiler (9) for burning an air-fuel mixture and creating a flame in the boiler (9), which burner (1) comprises a body part (6) to which connects an elongated burner head (2) which extends from the body part (6) and which can be adapted to the inside of the boiler (9). The outer end (2a) of the burner head (2) as seen from the body part (6) of the burner (1) is arranged to produce both a main flame (B) and a primary flame (E), which burner head (2) comprises an outer channel larger in diameter (3) for a mixture (80) of combustion air and fuel, and an inner channel (4) smaller in diameter, surrounded by said outer channel (3), for primary air (60) and primary gas (70).

Description

Burner and boiler-burner combination

The invention concerns a burner according to the preamble of claim 1 that can be installed in a boiler for burning a premixed air-fuel mixture.

The invention also applies to a boiler-burner combination according to claim 14, for burning a pre-mixed air-fuel mixture.

The so-called premix burners burn a mixture of premixed fuel and air. These burners aim for low NOx emission levels. In particular, premix burners with a long combustion head, which aim for low NOx emissions (less than 9 ppm NOx emissions in flue gases) without significant oxygen excesses, have been presented in the state of the art, e.g. in publication US-6,238, 206. This known burner design has a burner head connected to the body, which extends far into the boiler interior, and for low NOx emissions less than 12% or especially less than 6% oxygen excess is required. The biggest drawback of this burner is, as has been observed, the still relatively high NOx emission level, which in the future will not meet e.g. Some states in the United States — high emission standards, if the burner is to be run efficiently, i.e. with low oxygen excesses. From the applicant's own US application, this type of burner is known to achieve low emissions, but it has a limited suitability for boilers on the market.

The purpose of the invention is to provide an improvement to the prior art, or at least to alleviate the disadvantages of the prior art. Therefore, the first goal of the invention is to provide an efficient burner that can be installed in a boiler and a boiler-burner combination, where the premixed air-fuel mixture can be burned with the burner at low, less than 3% oxygen excess si-

So that the average NOx emissions in the flue gases remain below 15 ppm and below

S 25 with 7% excess oxygen so that the average NOx emissions in the flue gases remain below x 5 ppm. In particular, the invention aimed to achieve a NOx level below 2.5 ppm

N 8 20 with oxygen excesses with flame stabilization and phasing of mixture ratios.

E The second goal of the invention was to create a burner that can be better installed in different o boilers on the market, as well as a boiler & 30 burner combination that can be achieved in this way.

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S The above objectives are achieved with a burner that can be installed in a boiler according to claim 1 for burning a premixed air-fuel mixture and with a boiler-burner combination according to claim 14 for air-

to burn the fuel mixture and create a flame in the firebox inside the boiler.

More specifically, the invention concerns a burner according to claim 1 that can be installed in a boiler for burning the air-fuel mixture and forming a flame in the boiler. The burner comprises a body part, which is connected to an elongated burner head protruding from said body part, which can be fitted inside the boiler, whose outer end, viewed from the burner body part of the burner head, is arranged to create both a main flame and a primary flame, which burner head comprises an outer, larger-diameter channel for the mixture of combustion air and fuel, as well as for the primary air and the primary gas, surrounded by the outer duct, the smaller diameter inner duct. In this case, in the outer channel of the burner head, which extends from the body part of the burner to the outer end of the burner head, the supply of the premixed air-fuel mixture is arranged from the body part of the burner, or from the part of the burner head connected to the body part, which contains the premixed air-fuel in the flow direction of the mixture before the firebox, in order to form the main flame, a supply of primary gas and primary air is arranged in the inner channel of the burner head, which extends from the body part of the burner to the outer end of the burner head and which is surrounded by said outer channel.

In this case, the inner channel of the combustion head comprises an inner tube for gaseous fuel and an outer tube that surrounds said inner tube, whereby a flow space for primary air remains between the outer side of said inner tube jacket and the inner side of the outer tube jacket.

N In this flow space, a flow guide 25 is arranged at the outer end of the combustion head, which is arranged to control the primary air flow 3 passing through the flow space and

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In the direction of flow of the primary gas of the inner tube, the outer end has a nozzle = a set of nozzles for leading the primary gas into the flow state in the direction of flow of the primary air, 2 flow guides before or after it, whereby

LO ä 30 — -primary flame can be achieved by arranging the primary air supply from the body of the burner or from the part of the burner head connected to the body, which is located in the direction of the primary air flow before the firebox, in the air flow space between the outside of the jacket of the inner tube and the inside of the jacket of the outer tube, by arranging the inner channel primary gas supply to the inner tube from the body part of the burner or from the part of the burner head connected to the body part, which is located — in the direction of the primary air flow before the firebox. - by forming the space between the inner wall of the outer channel and the outer wall of the inner channel as a discharge channel, the center line of the discharge head forming an oblique angle of encounter with the longitudinal center line of the fire head, which angle of incidence is 90-140 degrees, when looking at the said discharge channel towards the mouth = pin of the burner body, in which case the main flame can be achieved by leading the premixed fuel-air mixture to the discharge channel, from which said fuel-air mixture can be introduced into the boiler to form the main flame.

In the boiler-burner combination according to the invention, in order to burn the air-fuel mixture and create a flame in the firebox inside the boiler, the burner is defined in claim 1, and is connected to the boiler in such a way that another part of the elongated burner head remains inside the boiler firebox, which protrudes from the frame part, and the first part of the burner head remains outside the boiler or is connected to the boiler structures. The main flame can be achieved by leading the pre-mixed air-fuel mixture to the discharge channel, from the mouth of which the mentioned fuel-air mixture discharges into the boiler at an angle of 90-140 degrees, when looking at the mouth of the discharge channel from the direction of the center line passing through the end of the burner body. .

Main flame (B) is available

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N by leading the pre-mixed air-fuel mixture to the discharge channel, through which the said fuel-air mixture discharges from the mouth opening of the discharge 3 25 —cup head, into the firebox, whereby

The center line of the said discharge head forms the angle of incidence of the bevel, which angle is

I about 90-140 degrees, with the longitudinal centerline of the burner head and also with the longitudinal centerline of the discharge channel, looking at the said discharge end of the discharge 2 channel from the direction of the burner body.

LO

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S 30 — Primary flame (E) is available

N by arranging in the flow mode, the supply of primary air from the body part of the burner or from the part of the burner head connected to the body part, which is located in the primary

in the direction of air flow before the firebox, to direct the flow of primary air to the flow controller, which is adapted to direct the flow of primary air towards the mouth opening of the flow space in the direction of the main flame and by arranging the supply of primary gas to the inner tube of the inner channel from the body part of the burner, or from the part of the fire head connected to the body part, which is located in the flow direction of the primary air before the firebox, in which case the nozzles of the set of nozzles near the free end of the inner pipe are adapted to direct the primary gas to discharge from the mouth opening of the firebox into the flow state.

The invention at hand is based on the fact that the firehead consists of two nested channels. In the outer channel, a premixed air-gas mixture flows, discharging into the firebox from the discharge end of the discharge channel, which narrows and turns away, as seen from the center line of the firehead. The cross-sectional area of the discharge channel decreases in the direction of flow of the premixed air-gas mixture as it moves towards the mouth opening of the discharge head, which is located at the mouth opening of the combustion head. — Primary air and primary gas flow in the inner channel. The primary air is guided towards the mouth opening of the fire head through a flow guide, such as vanes, in the direction of the main flame. The primary gas travels in the inner channel in its own pipe and is directed to the mouth opening of the fire head by means of nozzles.

The power and air volume of the primary flame are adjusted in the burner, and the adjustment is precise and — has a strong effect on the main flame. Thanks to the good adjustability, the burner is better suited to varied applications and furnaces than before. In particular, the burner is better suited to water-tube boilers and other special applications.

Thanks to more reliable adjustment, 5ppm can be achieved with the new burner

N emission limit with acceptable stability in furnaces that are more versatile than before 5 25 —. In addition to this, the new concept can achieve less than 2.5 ppm NOx level <Q with less than 8% oxygen excesses, thanks to more optimal flame stabilization and change of mixture ratios. Thanks to the innovative design of the burner head, the premix burner

The typical risk of developing a rear fire has been minimized, which improves both safety and comfort of use.

X 30 — In the following, the invention and the advantages that can be achieved with it are illustrated in more detail

S more directly by referring to the accompanying drawings.

Figure 1 shows a cross-sectional view of the body part of one embodiment of the burner and the burner head associated with it.

Figure 2A shows a front view of one embodiment of the flow controller located at the combustion end of the burner according to the invention.

Figure 2B also shows another embodiment of the flow controller located at the fire end of the burner according to the invention from the front. Figure 2C shows another embodiment of the flow controller located at the burner end of the burner according to the invention from a front view.

In the following, we will first briefly review which aspects of the burner according to the invention and the boiler-burner combination are explained in each of Figures 1, 2A, 2B and 2Cha. — Figure 1 shows a longitudinal section of the burner 1, whose burner head 2 extends into the boiler 9. The figure also shows the flame A, B, C. D, created inside the boiler.

E formation in the burner-boiler combination, by burning the air-fuel mixture 80 (primary flame B formation) or primary air 60 and primary gas 70 (primary flame E formation) directed to the mouth opening 23 of the combustion head. In Figure 1, arrows show the direction of travel of the air-fuel mixture 80, primary air 60 and primary gas 70 in the combustion head 2.

In Figure 1, the burner 1 is installed in the boiler 9 in such a way that the mouth opening 23 of the burner head 2 opens to the inside of the boiler 90 and the body part 6 of the burner is attached to the boiler 9 via the flange 91.

The elongated burner head 2 of the burner 1 protrudes from the body part 6 and the main flame B and the primary flame E are provided on the inside 90 of the boiler 9, which are located after the mouth opening 23 of the outer end 2a of the burner head as seen from the mentioned body part 6. A flame

The formation of N other zones (A, C, D) has been explained later.

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N x Combustion head 2 comprises an outer, larger-diameter channel 3 for combustion air and

N 25 — for the fuel mixture 80 and the inner channel 4 surrounded by the outer channel 3, smaller in diameter, primary air 60 and primary gas 70.

Ao a o The inputs of primary gas 70 and primary air 60 are arranged in the inner channel 4 of the combustion head 2, which is surrounded by the outer channel 3 of the combustion head 2. The inner channel of the fire head

N 4 extends from the body part 6 of the burner all the way to the mouth opening 2a of the outer end of the burner head 2

O

N 30 until 23.

The inner channel 4 of the burner head 2 comprises an inner tube 4:41 for gaseous fuel (primary gas) 70 and an outer tube 4;42. The outer tube 4:42 surrounds the mentioned inner tube 4:41. The outer surface of the jacket 40 of the inner tube 41 (i.e. the turned side of the outer tube of the inner tube jacket 41) and the outer tube 4; A flow space 4:43 for the primary air 60 remains between the inner surface of the jacket 42a (ie the side of the jacket 42a of the outer tube turned to the inner tube).

The flow state 4:43 of the primary air 60 extends from the body part 6 of the burner 1 to the mouth opening 23 of the outer end 2a of the burner head 2 (as seen from the body part 6). — The free end 42A of the outer tube 42 turns outwards, i.e. in the direction of the free end 31A of the outer wall 31 of the outer channel 3, viewed from the center line of the outer tube, i.e. the same center line P of the fire end (cf. Figure 1). Said free end 31A of the outer wall 31 is located on the arc of a circle whose radius is R1, so that the outer tube 4; 42 free end 42A looks like a trumpet. — The supply of primary air 60 from the body part 6 of the burner 1 or from the part 2b of the burner head 2 connected to the body part 6, which is located in the flow direction of the primary air 60 before the firebox 90, is now arranged in this flow space 43.

The primary air 60 thus travels in the flow space 43, from the end 43b on the side of the body part 6 of the burner 1 of said flow space 43 all the way to the free end 43a — of the flow space 43. The free end 43a of the flow space 43 is located at the outer end 2a of the combustion head 2.

From the free end 43a of the flow space 43, the primary air 60 flows to the mouth opening 23 of the combustion head 2.

To the free end 43a of the flow space 43, before the flow space 43 and at the same time to the combustion end

In the mouth opening 23 of the outer end 2a, a flow guide 7 is installed.

O 25 —is thus located at the outer end 2a of the firehead 2, close to the mouth opening 23 of the firehead.

S The flow controller 7 directs the flow of the primary air 60 passing through the flow space 43 = to flow in the direction of the main flame B, when said primary air 60 exits the flow

E from state 43. The structure and operation of the flow controller 7 are described in more detail o below with figures 2A-2C.

X 30 The outer channel 3 of the burner?2 extends in turn from the body part of the burner 1 to the burner

S 2 for the mouth opening 23 of the outer end 2a. The outer wall 31 of the outer channel 3 forms the outer wall of the fire end 2 at the same time. The free end 3A of the outer channel 3, i.e. the free end 31A of the outer wall 31 turns outwards from the center line of the discharge channel 10

10L when viewed (cf. Figure 1) with a radius of curvature R, in which case the outer wall 31 of the outer channel 31 also resembles a trumpet in appearance at the mouth opening 23 of the fire head 2.

The space between the inner side 30 of the outer wall 31 of the outer channel 3 and the outer side of the jacket 42a of the inner channel 4 forms the discharge channel 10, where the premixed air-fuel mixture 80 passes to form the main flame B. The jacket 42a of the outer pipe 42 delimits the inner channel 4 and thus functions as the jacket of the inner channel.

As mentioned above, the free ends 31A and 42A of the outer wall 31 of the discharge channel 10 and the inner wall of the discharge channel, i.e. the jacket 42a of the outer tube 42, are both "trumpet-like" in general shape at the outer end 2a of the combustion head 2. Corresponding to the outer wall 31 of the discharge channel 10 and the inner wall 42a of the discharge channel — the free ends 31A and 42A are thus respectively curved outwards from the center line 10L of the discharge channel and from the center line P of the fire head, their radii of curvature being R and R1, respectively, where R and R1 are the same or different.

Since the free end 31A of the outer wall 31 of the discharge channel 10 and the free end 42A of the inner wall 42a of the discharge channel curve outward, respectively, as seen from the center line 10L of the discharge channel 10a and from the center line P of the fire head 2, the entire discharge head 10a is oriented away from the center line P of the fire head.

Since the discharge channel 10a is itself ring-shaped, the central line of the discharge channel 10L here means the ring of the ring-shaped discharge channel 10a

N-shaped center line 10L viewed in the longitudinal section of the discharge channel

O 25 — (cf. Fig. 1). In this case, the center line 10 L of the discharge head 10a of the discharge channel 10 (in the longitudinal section of the discharge head x) forms an oblique meeting angle t of the fire head 2 pi-

N with the longitudinal center line P and also with the center line 10L of the discharge channel 10 (longitudinal cut). The mentioned incident angle t is about 90-140 degrees, = when looking at the mentioned discharge end of the discharge channel 10 10a of the body of the burner 1

O 30 from 6 directions.

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N Generally, the free end 42A of the inner wall 42 of the discharge channel 10 (the free end of the outer tube 42

N end 42A), which has a radius of curvature R1, curves more strongly than the free end 31A of the outer wall 31 of the discharge channel 10, which has a radius of curvature R, so that R >

R1. In this case, the entire discharge end 10a of the discharge channel 10 narrows and turns outwards when the premixed air-gas mixture 80 is transported in the direction of travel towards the mouth opening of the discharge end 10a of the discharge channel 10, which is part of the mouth opening 23 of the fire head (cf. Figure 1). In this case, the cross-sectional area of the discharge head 10a of the discharge channel 10 also decreases in the direction of flow of the premixed air-gas mixture 80 as it moves towards the mouth opening of the discharge head 10a, which is located at the mouth opening 23 of the combustion head 2.

Thanks to the new design of the discharge head 10a of the discharge channel 10, the risk of backfire typical for premix burners is minimized, which improves both safety and comfort of use.

In the discharge channel 10 of the outer channel 3, the supply of the premixed air-fuel mixture 80 is arranged to form the main flame B shown in Figure 1. The premixed air-fuel mixture 80 arrives in the discharge channel 10 of the outer channel 3 from the body part 6, or from the part 2b of the combustion head 2 connected to the body part, which is located in the flow direction of the premixed air-fuel mixture before the combustion chamber 90. — Primary gas of the inner tube 4;41 70 in the direction of flow at the outer end 41a, on the other hand, has a set of nozzles 8 for leading the primary gas 70 to the flow state 4:43. The primary gas is introduced into the flow space in the direction of the flow of the primary air 60 before or after the flow controller 7 located at the free end 43 of the flow space 43. The supply of the primary gas 70 from the body part 6 of the burner 1 or from the part connected to the body part 6 is arranged in the inner pipe 4;41 of the inner channel 4 from part 2b of the combustion head 2, which is located in the flow direction of the primary gas 70 before the firebox 90.

The primary flame E is formed when the flow of primary air 60 and primary gas 70 fed into the flow space 43 combine after the mouth opening of the flow space 43. The mouth of the flow state

The N opening is part of the firehead 2 mouth opening 23.

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5 25 Figures 2A, 2B and 2C illustrate, viewed from the front, according to the invention? the structure and operating options of the flow controller 7 installed in the flow space 43 of the inner channel of the burner. In addition, a flow controller is drawn on each image

E 8 incoming primary air flow 60 and to the same flow space 43 from the inner pipe o 4; 41 incoming flow of primary gas 70;701.

O a 30 — As shown in Figure 1, the flow of primary air 60 is arranged to flow through the burner

S from the body part 6 to the flow space 43 and further through the flow guide 7.

The flow controller 7 used to control the primary air 60 can have different structures and shapes, however, the most important thing is that the flow controller 7 directs the flow of the primary air 6 arriving at the flow controller 7 from the flow space 43 towards the main flame B. The main flame is created in the discharge channel 10 by the air-fuel-flowing with the help of mixture 80.

The flow guide 7; 7a can comprise, for example, as shown in Figure 2A, a set of vanes 71, 7?, 73...7". The vanes 71, 72, 73... 7" of the flow guide 7: 7a are installed to rotate the inner tube 4; 41 at the same distance from the free end 41A of the inner tube 41.

The surface area and orientation of each vane 71, 72, 73...7" with respect to the flow of primary air 60 passing between two adjacent vanes (e.g. 7! and 7? or 7? and 73) — is adjusted such that said flow of primary air 60 is directed after the vanes 7 towards the flow space 43 and at the same time the mouth opening 23 of the burner head 2 in the direction of the main flame B. Preferably, the flow of primary air 60 is directed near the inner surface of the outer tube 4;42 due to the effect of the flow guide 7.

The vanes 71, 72, 73...77 are at least partially transverse to the primary air 60 — flow direction 60 in the flow state 43. Preferably, the vanes 71,72.73...7n are at an angle of 20-90 degrees to the primary air flow direction 60.

In Figure 2B, the flow guide 7; 7b consists of one circular plate that goes around the inner tube 41, and the plane of the plate is transverse to the longitudinal direction of the inner tube 41. The plate has grooves parallel to its radius at a distance from each other, whereby the flow of primary air 60 arriving on the lower surface of the plate is directed from the grooves towards the mouth opening 23 of the flow space 43 in the direction of the main flame B.

Figure 2C shows another embodiment of the flow controller 7c. The flow guide 7;7c consists of one circular plate that goes around the inner tube 41, and le-

The plane of the N vy is transverse to the longitudinal direction of the inner tube 41. The flow of primary air 60 arriving at the lower surface of the plate goes around the plate and is directed towards the mouth opening 23 of the flow space <Q 43 in the direction of the main flame B.

N z In the following, some important details of the invention will be examined. a

O Flow mode 4; 43 expands when moving towards the mouth opening 23 of the combustion head 2, because the free end 42A of the outer tube jacket 42, which acts as the outer wall of the current space 43, curves

O 30 — looking away from the center line P of the fire head 2. .

Thanks to the reliable adjustment of the main flame B, the burner can achieve an emission limit of 5ppm with acceptable stability in several furnaces that were previously difficult to control. In addition to this, the new concept can achieve a NOx level of < 2.5 ppm (02 ref 3%) in the firebox thanks to more optimal flame stabilization and phasing of mixture ratios.

The primary air 60 is fed to create the primary flame E 5-30% of the total amount of air fed to the combustion head?2 of the burner, and by adjusting the mutual amount and flow rate of the primary air 60 and the primary gas 70, the power of the primary flame E can be precisely controlled. This strongly affects the power and stability of the main flame B. Preferably, the primary air 60 is supplied to create the primary flame E about 20% of the total amount of air used to create the main flame B — via the premixed air-gas mixture 80 and to create the primary flame E via the primary air 60.

All the premixed air and fuel are fed to area B of the main flame, i.e. in figure 1

To the B-zone, in which zone the majority of burning takes place. A primary flame E is formed at the mouth opening 23 of the burner head, the temperature of the flue gas flowing into the zone B of the main flame can be influenced by adjusting its power and air volume. In this way, the stability and emissions of the burner 1 can be optimized for various applications and furnaces. Thanks to the good adjustability, the burner is better suited to varied applications and furnaces than before. In particular, burner 1 is even better suited for water-tube boilers and other special applications. — In the A-flame zone shown in Figure 1, a little burning also takes place, the fuel and air end up in the A-flame zone from the B-zone of the main flame. The flue gas circulates in the A zone and cools at the same time. The flue gas cooled in the A-zone finally returns to the B-zone of the main flame, lowering the temperature of the main flame and reducing the burner's NOx emissions. Also from zone C of flame C flows to main flame B-

N 25 — partly cooled flue gas in the zone, which both dilutes and cools

N B zone, cooling the flame temperature profile and thus reducing the burner's NOx-3 emissions.

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- There is a strong return flow in front of the firehead 2 mouth opening 23. The flue gas exits = from the B-zone of the main flame along the walls of the boiler 9, cooling at the same time and part of it burns

O 30 — back through the central part of the firebox 9 as return flow D-C. The return flow D-C both i. stabilizes the flame and cools and dilutes the B-zone formed by the main flame. Lie-

Ok, in the D-zone, at the end of the firebox 90, there are no significant return flows, but carbon monoxide is still burnt out there.

Main parts reference numbers

Burner 1

Fire head 2 outer end 2a part of the fire head before the firebox 2b mouth opening 23

Outer channel 3 free end 3A outer wall 31 inner 30 free end 31A

Inner channel 4 inner pipe :41 jacket 41a outer wall 40

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N outer tube 42

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< No. free end 42A

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- sheath 42a = o 20 flow state 43 2

N free end 43a

O

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Burner body part 6

Flow guide 7 vanes 71.72, 73.7"

Nozzles 8

Inside of the boiler 9, firebox 90 — Flange of the connection between the boiler and the burner 91

Discharge channel 10 discharge head 10a

Primary air 60

Primary air discharged from the mouth opening 602 — Primary gas 70 primary gas discharged into the flow state 701

Premixed air-fuel mixture 80

Return flame A

Main flame B — Side flame immediately behind primary flame C

Farther side flame behind the primary flame D 3 Primary flame E

S Longitudinal centerline of the fire end P = Radius of curvature R of the free end of the outer channel

O 20 Radius of curvature of the free end of the outer tube R1

O

3 Center line of discharge channel 10L - Center line of discharge head 10A

Claims (19)

Patent Claims 1. = A burner (1) that can be installed in the boiler (9) for burning the air-fuel mixture and creating a flame in the boiler (9), which burner (1) comprises a body part (6) connected to the said body part (6 ) protruding elongated fire head (2) that can be fitted inside the boiler (9), the outer end (2a) of the fire head (2) viewed from the body part (6) of the burner (1) is arranged to create both the main flame (B) and the primary flame ( E), which combustion head (2) comprises an outer, larger-diameter channel (3) for the combustion air and fuel mixture (80) and a smaller-diameter inner channel (4), surrounded by said outer channel (3), for primary air (60) and for the primary gas (70), in which case the supply of the premixed air-fuel mixture (80) to the outer channel (3) of the burner head (2), which extends from the burner body part (6) to the outer end of the burner head (2a), is arranged from part (6), or from it connected to the body part - only the part of the combustion head (2), which is located in the direction of flow of the premixed air-fuel mixture (80) before the firebox (90), to form the main flame (B), into the interior of the combustion head (2) in the channel (4), which extends from the body part (6) of the burner to the outer end (7) of the combustion head (2) and which is surrounded by said outer channel (3), the supply of primary gas (70) and primary air (60) is arranged, known for , that —- the inner channel (4) of the combustion head (2) comprises an inner tube (4;41) for gaseous fuel (70) and an outer tube (4:42) that surrounds said inner tube (4;41), whereby said inner tube (4) :41) the outer side of the jacket (41a) and the outer tube (4; 42) between the inner side of the jacket (42a) there is a flow space (4,43) for the primary air (60), N N N in which a flow controller (7) is arranged at the outer end (2a) of the combustion head (2) in the flow space (4;43) , which is arranged to control the flow of N primary air (60) passing through the flow state (43) and I = whose inlet pipe (4;41) in the direction of flow of the primary gas (70) at the outer O end (41a) has a set of nozzles (8) to lead the primary gas (70) into the flow state i. (4:43) in the flow direction of the primary air (60) before the flow guide (7) or after the flow guide (7), in which case the -primary flame (E) can be achieved by arranging the inner tube of the inner channel (4) (4:41) supply of primary air (60) from the body part (6) of the burner (1) to the flow space (4;43) between the outside of the jacket (41a) and the inner side of the outer tube (4; 42) of the jacket (42a) or from it to the body part ( 6) from the connected part of the burner head (2), which is located in the flow direction of the primary air (60) before the firebox (90), by arranging the supply of the primary gas (70) from the body part of the burner (1) to the inner tube (4;41) of the inner channel (4) (6), or from that part of the fire head (2) connected to the body part (6), which is located in the flow direction of the primary air (60) before the firebox (90), -by forming the inner side of the outer wall (31) of the outer channel (3) ( 30) and the space between the outer wall (42) of the inner channel (4) as a discharge channel (10), the center line (10L) of the discharge head (10a) or its extension forms an oblique meeting angle (t) of the longitudinal center line (P) of the fire head (2) with which the incident angle (t) is 90-140 degrees, looking at said discharge channel (10) from the — direction of the body (6) of the burner (1), in which case the main flame (B) can be achieved by leading the premixed fuel-air mixture (80) into the discharge channel (10), from which said fuel-air mixture (80) can be introduced into the firebox (90) to form the main flame (B). 2. The burner (2) according to claim 1, characterized in that the flow guide (7) comprises a set of fins (71, 72, 73...7"), the surface area and orientation of which — to the primary air passing between them ( 60) relative to the flow is adapted such that the flow of the primary air (60) is directed after the mentioned vanes towards the mouth of the flow space (43), discharging into the firebox (90) in the direction of the main flame (B). 3. Burner according to claim 1, characterized in that the flow guide N (7) consists of a circular plate that goes around the inner tube (4; 41), whose S 25 — plate plane is transverse to the longitudinal direction of the inner tube (4:41). S 4. Burner (1) according to one of the above claims 2-3, characterized in that the flow guide (7) comprises a plate or vanes (71,72,73..7"), which/ E are installed to rotate inner tube (4;41) at the same distance from the free end of the inner tube o (41A), which plate or vanes (71, 72, 73...) is/are at least & 30 — partially transverse to the direction of flow of the primary air (60). N S 5. Burner (1) according to claim 4, characterized in that the vanes (71, 72, 73...7") of the vane set are at an angle of 20-90 degrees with respect to the direction of flow of the primary air (60). 6. Burner (2) according to one of the above claims, characterized in that the flow guide (7) is adapted to direct the flow of the primary air (60) in the vicinity of the inner side of the jacket (42a) of the outer tube (4;42) of the inner channel (4). 7. Burner (1) according to one of the above claims, characterized in that the flow space (4; 43) of the inner channel (4) expands when moving towards the mouth opening (23) of the burner head (2) at the free end (43a) of the flow space (43) . 8. A burner (1) according to one of the preceding claims, characterized in that the nozzles of the set of nozzles (8) in the vicinity of the free end (4a) of the inner tube (4) are arranged to lead the primary gas (70) from the inner tube (4,41) into the flow space (4 :43) in the flow direction of the primary air (60) before or after the flow controller (7) located at the free end (4; 43a) of the flow space (4;43). 9. Burner (1) according to one of the preceding claims, characterized in that the discharge channel (10) is arranged to narrow and turn away, viewed from the center line (P) of the fire end, when the premixed air-gas mixture (80) is transported in the direction of travel towards the discharge channel ( 10) the mouth opening of the discharge head (10a), which is part of the mouth opening (23) of the fire head (2). 10. Burner according to claim 9, characterized in that the cross-sectional area of the discharge channel (10) decreases in the direction of flow of the premixed air-gas mixture — (80) when moving towards the mouth opening of the discharge head (10a), which is located at the mouth opening (23) of the combustion head. . 11. Burner (1) according to claim 9 or 10, characterized in that the outer wall (31) of the discharge end (10a) of the discharge channel (10) is located on the arc of a circle N whose radius is R and which outer wall (31) curves at the discharge end ( 10a) S 25 — away from the center line (P) of the combustion head (2). N > 12. Burner (1) according to one of claims 9-11, characterized in that = the free ends (31A) and (42A) of the outer wall (31) of the discharge channel (10) and the inner wall O (42a) of the discharge channel (10) curve outwards towards the burner head from the center line (P) i. viewed and with the radii of curvature (R) and (R1) being the same or different. N O N 30 13. The burner (1) according to claim 12, characterized in that the free end (42A) of the inner wall (42) of the discharge channel (10), which has a radius of curvature (R1), curves more strongly than the free end (31A) of the outer wall (31) of the discharge channel (10), which has a radius of curvature R, so that R > R1. 14. Boiler-burner combination, for burning the air-fuel mixture (80) and creating a flame (B, E) in the firebox (90) inside the boiler, which burner (1) is defined in claim 1 and connected to the boiler (9) in such a way, that the second part of the elongated burner head (2) that protrudes from the body part (6) remains inside the boiler firebox (90), and that the first part of the burner head (2) remains outside the boiler (9) or is connected to the structures of the boiler (9), known for that the main flame (B) can be achieved by leading the pre-mixed air-fuel mixture (80) to the discharge channel (10), from the mouth of the discharge head (10a), said fuel-air mixture (80) discharges into the firebox (90), whereby the said discharge head (10a) the center line (10L) or its extension forms an oblique meeting angle (t), which angle (t) is approximately 90-140 degrees, at the longitudinal center line (P) of the fire head (2) and also the discharge channel (10) — the longitudinal center line (10L) with, looking at the mentioned discharge end (10a) of the discharge channel (10) from the direction of the body part 6 of the burner 1 and . -primary flame (E) can be achieved by arranging the supply of primary air 60) to the flow space (4;43) from the body part (6) of the burner (1) or from the part of the burner head (2) connected to the body part, which houses the primary -in the flow direction of the air (60) before the firebox (90), in order to direct the flow of the primary air (60) to the flow controller (7), which is adapted to direct the flow of the primary air (60) towards the mouth of the flow space (43) of the main flame N (B) parallel and N x arranging the inner channel (4) in the inner tube (4;41) of the primary gas (70) N 25 — supply from the body part (6) of the burner (1) or from it connected to the body part (6) > burner head (2) from the part that is located in the flow direction of the primary air (60) before the fuel = liquor (90), in which case the nozzles of the set of nozzles (8) near the free end (4a) of the inner tube (4:41) are adapted to direct the discharge of the primary gas (70) - i. from the mouth of the firehead of the earth (2a) to the flow state (4:43). N O N 30 15. Boiler-burner combination according to claim 14, characterized in that the primary gas (70) is fed from the inner pipe (4;41) via nozzles (8) (8) into the flow space (4;43) in the direction of flow of the primary air (60) before or after the flow guide (7) at the free end (43a) of the flow space (4:43). 16. Boiler-burner combination according to claim 14, characterized in that the discharge channel (10) narrows and turns outwards as seen from the center line (P) of the combustion head, when traveling the premixed air-gas mixture (80) in the direction of travel towards the discharge end (10a) of the discharge channel (10) , whereby the speed of said air-gas mixture (80) increases as it flows towards the mouth opening of the discharge end (10a) of the discharge channel (10). 17. Boiler-burner combination according to claim 16, characterized — in that the return flow of the flame together with the flow controller (7) is adapted to control the flow of the primary air (60) passing through the flow controller (7) towards the mouth opening of the flow space (43) , near the inner surface of the outer tube. 18. Boiler-burner combination according to claim 14, characterized in that by adjusting the amount and speed of primary air (60) and primary gas (70) — the power of the primary flame (E) is controlled, which affects the power and stability of the main flame (B). 19. Boiler-burner combination according to claim 14, characterized in that primary air (60) is supplied to create the primary flame (E) 5-30% of the total amount of air that is used to create the main flame (B) — a premixed air-gas mixture ( 80) and to create the primary flame ( E ) through primary air. N N O N <+ <Q N I a a o ™ LO N N O N