CN113195976A

CN113195976A - Assembly and method for injecting gaseous combustion agents

Info

Publication number: CN113195976A
Application number: CN201980083376.4A
Authority: CN
Inventors: 伯诺瓦·格朗; S·朱玛; 泽维尔·波贝尔; J-B·塞内加尔
Original assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Current assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Priority date: 2018-12-21
Filing date: 2019-11-28
Publication date: 2021-07-30
Also published as: ES2894624T3; WO2020126401A1; EP3671038B1; EP3671038A1; BR112021011579A2; JP2022514328A; US20220074592A1; MX2021007420A

Abstract

An assembly for injecting a gaseous combustible substance into a combustion zone, comprising: a chamber (11); at least one main injector (21) for delivering a main flow of gaseous agent from the chamber (11) towards the combustion zone (1) and injecting the main flow into the combustion zone (1); at least one auxiliary injector (22) for delivering an auxiliary flow of the agent from the chamber (11) towards the combustion zone (1) and injecting the auxiliary flow into the combustion zone (1); a pressure detector (30) for detecting a gas pressure or a gas pressure change in the chamber (11); a regulation system (31) for regulating the orifice section of at least one auxiliary channel fluidly connecting the at least one auxiliary injector (22) to the chamber (11); and a control system (32) connected to the pressure detector (30) and the regulation system (31), the control system (32) operating the regulation system (31) such that the orifice cross-section of the at least one auxiliary channel is regulated in accordance with the pressure or pressure variation detected by the pressure detector (30).

Description

Assembly and method for injecting gaseous combustion agents

The present invention relates to an assembly for injecting a gaseous combustible substance into a combustion zone, a burner comprising such an assembly, and the use of such an assembly/burner in a combustion process.

In industrial combustion processes, for example for converting loads (melting, heating, recovery furnaces, etc.), specific flame characteristics, in particular flame shape and length adapted to the combustion chamber and/or to the load intended to be heated, are sought, in order to obtain a determined heat transfer curve and to optimize the production quality and the lifetime of the equipment.

The flame characteristics are determined in particular by the nature of the combustion agents (fuel and oxidant) and how these are introduced into the combustion zone (flow rate, velocity, spatial distribution, etc.).

Thus, ｃA burner comprising ｃA device for supplying an oxygen-enriched oxidant (at least 80% O) is known from EP-A-0763692₂) A first inner channel for supplying fuel externally around the first oxidant supply channel, and a second outer channel for supplying oxidant externally around the channel supplying fuel. According to EP- ｃA-0763692, the burner comprises means for varying the flow rate of the oxidant injected through the first internal passage, which allows controlling the characteristics of the flame, such as flame length and luminosity.

Similarly, from EP- ｃA-1016825, the use of ｃA burner comprising ｃA first inner channel for supplying an oxidizing agent, an intermediate channel for supplying fuel externally around the first oxidizing agent supply channel, and ｃA second outer oxidizing agent supply channel externally around the fuel supply channel, for heating the molten glass transfer passage during glass production, and for adjusting the length of the flame produced by said burner by varying the ratio of the total flow of oxidizing agent through the first oxidizing agent supply channel is known.

The aforementioned burners are burners that inject fuel and oxidant concentrically and adjacently to produce a flame having a substantially circular cross-section.

Other burners produce a flame known as a "flat flame" and/or inject at least some oxidant at a distance from the fuel injection, even at a distance from the oxidant injection.

Thus, EP- ｃA-2143999 describes ｃA burner comprising:

at least two gaseous fuel passages;

at least one oxidant passage; and

at least one outlet surface in which the at least one gaseous fuel passage or the at least one oxidant passage terminates.

This known burner also comprises:

means capable of supplying an oxidant stream, and means for injecting said oxidant stream into at least one oxidant channel; and

means capable of supplying at least one gaseous fuel stream, and means for injecting the gaseous fuel stream into the at least two gaseous fuel channels,

to produce at least one jet of oxidant and at least two jets of gaseous fuel which meet in a combustion zone downstream of the burner.

According to EP- ｃA-2143999, the at least two gaseous fuel passages each comprise an inner passage and ｃA coaxial outer passage.

The means for controlling the flow of gaseous fuel regulates the flow of gaseous fuel through the inner passage and the outer passage, respectively, by the gaseous fuel distributor.

This allows both the heat transfer curve and the flame length to be controlled.

If it is thus known that it is possible to vary certain characteristics, in particular the length of the flame produced, by adjusting the distribution of the flow of fuel or oxidant over a plurality of concentric channels/injectors, the known burner does not comprise any feedback means that allows to adjust in real time the operation of the burner, and therefore the target characteristics of the flame.

Surprisingly, it has now been found possible to generate such a feedback system based on the detected pressure of the gaseous combustion agent before it is dispensed.

The present invention relates to an assembly for injecting a gaseous combustion agent selected from a gaseous fuel and a gaseous oxidant into a combustion zone.

The assembly comprises a chamber and the agent is introduced into the assembly via an inlet of the chamber.

The assembly comprises at least one main injector for conveying a main flow of agent from the chamber towards the combustion zone and for injecting said main flow into the combustion zone. To this end, the at least one main injector is fluidly connected to the chamber by at least one channel (referred to as main channel).

The assembly further comprises at least one auxiliary injector for conveying an auxiliary flow of the agent from the chamber towards the combustion zone and for injecting said auxiliary flow into the combustion zone. The at least one auxiliary injector is in turn fluidly connected to the chamber by at least one passage (referred to as an auxiliary passage). The at least one auxiliary channel has an adjustable flow cross-section.

For example, a regulating system in the form of a valve allows this flow cross section of the at least one auxiliary channel to be regulated.

The assembly further comprises a pressure detector for detecting a pressure or gas pressure change in the chamber, and a control system connected to the pressure detector.

The control system is also connected to a system for regulating and controlling the regulating system such that the flow cross-section of the at least one auxiliary channel is regulated in dependence on the pressure or pressure change detected by the pressure detector of the assembly.

According to one embodiment, the control system, which may be an analog or digital control system, is adapted to control the regulation system such that the gas pressure in the chamber is in a predetermined pressure zone by regulating the flow cross section of the at least one auxiliary channel.

According to another embodiment, the control system is adapted to control the regulation system such that the gas pressure in the chamber corresponds to a value predetermined by adjusting the flow cross-section of the at least one auxiliary channel.

It is noted that the zone or predetermined pressure range may be constant over time, but may also vary over time, for example:

according to the steps of a method (such as a melting method or a heating method using the assembly), which may be cyclic or acyclic;

depending on the power required in the combustion zone; or

Depending on the feedback parameter rather than the pressure in the component chamber.

The above description also applies to the predetermined value of the gas pressure.

As noted above, the system for controlling the assembly may be an analog or digital system. It may be mechanical, e.g. pneumatic or hydraulic. Preferably, the control system is digital. According to a preferred embodiment, the control system is programmable. In this case, in order to implement the jetting assembly according to the invention, the control system is programmed to control the regulating system so as to activate the regulating system in dependence on the pressure or the pressure variation detected by the pressure detector. The gas pressure or gas pressure change detected by the pressure detector is then transmitted to the programmable control system: for example by a wired connection or a wireless connection.

The regulation system may comprise various means for regulating the flow cross-section of the at least one auxiliary channel, such as one or more adjustable valves positioned in the at least one auxiliary channel between the chamber and the at least one auxiliary injector; or various means for regulating the movement of the mechanical element acting as a valve for the at least one auxiliary channel, wherein the movement is generated, for example, by translation, by rotation (screwing), or by deformation of the mechanical element connected to the valve, or even by changing the magnetic state of the metal element.

According to a simple and reliable embodiment, the regulating system is provided with at least one valve capable of regulating the flow cross-section of the at least one auxiliary channel by at least partially plugging said channel.

Such a regulation system may in particular take the following form. The at least one auxiliary channel fluidly connecting the at least one auxiliary injector to the chamber has an inner surface in the form of a funnel, and the regulating system comprises a valve having a corresponding outer surface, and the valve is movable along a longitudinal axis of the auxiliary channel. When the valve is thus moved along said longitudinal axis, the outer surface of the valve is moved towards or away from the inner surface of the auxiliary channel and the flow cross-section of said channel is reduced or increased, respectively.

It should also be noted that it is advantageous for the regulating system to be designed such that the flow cross-section of the at least one auxiliary channel is never completely closed. Indeed, in order to provide sufficient cooling for the at least one auxiliary injector, and/or to avoid clogging of the at least one auxiliary injector (e.g., due to deposition of condensable matter present in the atmosphere of the combustion zone, or soot formation due to overheating of gaseous fuel in contact with the at least one auxiliary injector), a minimum flow of gas through the at least one auxiliary injector may be required. However, it may also be considered to ensure such a minimum gas flow using means other than the regulating system defined above, such as fluid channels which short-circuit the valve and are small to simply ensure such a minimum flow.

The components are generally made of metal, wherein the injector or at least the downstream end (injection end) is generally advantageously made of a metal that is highly heat-resistant and oxidation-resistant, such as

(Inconel) type nickel-chromium austenitic steel alloy or

(Cortle) type nickel-free alloys.

The assembly according to the invention may more particularly comprise: at least one pair of main and auxiliary injectors, wherein one pair of main and auxiliary injectors surrounds the other pair of main and auxiliary injectors.

Thus, the main injector of the pair may surround the auxiliary injector, or the auxiliary injector may surround the main injector.

According to an advantageous embodiment, the main injector of the pair is surrounded by the auxiliary injector of the pair.

According to a particular embodiment, the main injector and the auxiliary injector of this pair are concentric. However, in some cases, a non-concentric arrangement may be useful.

It is to be noted that such a paired configuration does not exclude the presence of other elements, in particular the presence of one or more other injectors in or around any one of the injectors of the pair.

For example, according to a particular embodiment, the fluid may be a gaseous oxidant, such as a gas comprising at least 80 vol% (volume percent), and preferably at least 90 vol% oxygen. The main injector of the pair is centrally located and surrounded, preferably concentrically, by the auxiliary injector of the pair. The injector for injecting fuel into the combustion zone is located between the main injector and the auxiliary injector of this pair, so that the fuel injector surrounds the main oxidant injector and is surrounded by the auxiliary oxidant injector, the assembly thus forming part of a burner for (at least partial) combustion of fuel and oxidant, and wherein the flow cross section of the auxiliary injector, and thus the distribution of oxidant between the main flow and the auxiliary flow, is adjusted by the control system by means of the adjustment system in accordance with the gas pressure or the variation in gas pressure in the assembly chamber detected by the pressure detector.

According to another similar embodiment, the fluid is a gaseous fuel, such as natural gas. The main injector of this pair is centrally located and surrounded, preferably concentrically, by the auxiliary injector. An injector for injecting oxidant into the combustion zone is located between the main and auxiliary injectors of the pair such that the oxidant injector surrounds the main fuel injector and is surrounded by the auxiliary fuel injector. The oxidant is preferably a gas comprising at least 80 vol%, and more preferably at least 90 vol% oxygen. The assembly thus forms part of a burner for the (at least partial) combustion of fuel and oxidant, and in which the flow cross section of the auxiliary injector, and thus the distribution of fuel between the main and auxiliary flows of fuel, is adjusted by the control system by means of the adjustment system in accordance with the gas pressure or the variation in gas pressure in the assembly chamber detected by the pressure detector.

The assembly according to the invention may comprise a single main injector and a single auxiliary injector, in particular a single pair of main and auxiliary injectors.

According to an alternative embodiment, the assembly according to the invention comprises a plurality of main injectors and/or a plurality of auxiliary injectors, in particular pairs of main injectors and auxiliary injectors.

According to a particular embodiment, the at least one auxiliary injector of the assembly is spaced apart from the at least one main injector of the assembly, while the at least one main injector of the assembly does not surround the auxiliary injector of the assembly, and the at least one auxiliary injector of the assembly does not surround the main injector of the assembly.

In this case, the at least one main injector may in particular extend into a first plane, while the at least one auxiliary injector extends into a second plane, wherein the second plane is parallel to the first plane. In this way, it is possible to inject the main and auxiliary flows of gaseous combustion agent into the combustion zone along two parallel planes.

According to an alternative embodiment, the at least one main injector extends into a first plane and the at least one auxiliary injector extends into a second plane, wherein the first plane and the second plane intersect downstream of said main injector and auxiliary injector, i.e. within the combustion zone into which the gaseous combustion agent is injected.

The assembly according to the invention may comprise at least two main injectors and/or at least two auxiliary injectors, preferably at least two main injectors and at least two auxiliary injectors. This is particularly advantageous in case the at least one main injector extends into a first plane and the at least one auxiliary injector extends into a second plane different from the first plane as described above.

For injecting the gaseous agent into the combustion zone, the inlet of the assembly (also the inlet of the chamber of the assembly) is fluidly connected to a source of gaseous fuel, preferably a source of gaseous fuel selected from the group consisting of natural gas, biogas, propane, butane, residue gas of a steel or methane reforming process, hydrogen, any mixture of said gaseous fuels, or to a source of gaseous oxidant, preferably a source of gaseous oxidant having an oxygen content of 21 to 100 vol%, preferably more than 21 vol%, and in particular at least 80 vol%, more preferably at least 90 vol%.

Such source may be a tank of gaseous agent in gaseous form or in liquefied form, a supply conduit for conveying the gaseous agent, or a generator of the gaseous agent.

The invention also relates to a device comprising a plurality of assemblies according to any of the above embodiments. In this case, it may be preferred that the apparatus comprises a common control system capable of controlling, preferably independently, the system for regulating each component of the apparatus in dependence on the gas pressure or gas pressure variation detected by the pressure detectors of said components.

As noted above, the assembly may be incorporated into a combustor.

Such a burner according to the invention therefore comprises an assembly according to any one of the preceding embodiments for injecting a gaseous combustion agent selected from a gaseous fuel and a gaseous oxidant into the combustion zone.

Such combustors also typically include at least one additional injector for injecting additional fluid into the combustion zone. As a general rule, the at least one additional injector is adapted to inject gaseous oxidant into the combustion zone when the gaseous agent injected by the assembly is a gaseous fuel, and to inject fuel (gaseous or non-gaseous) into the combustion zone when the gaseous agent injected by the assembly is a gaseous oxidant.

According to one embodiment, a combustor includes a block having an inlet face and an outlet face opposite the inlet face. The combustion zone is located downstream of the outlet face.

In contrast to assemblies, blocks are generally made of refractory materials (such as cement or electrofused type materials) or pressed materials (mainly consisting of alumina and/or zirconium and/or silica and/or magnesia or mixtures of these components, the proportions of which vary according to the application method).

The assembly is then attached to the inlet face of the block such that the injectors of the combustor, and thus the injectors of the assembly, are positioned in one or more perforations through the block from the inlet face to the outlet face.

Thus, a burner according to the invention may for example comprise such a block with one or more first perforations terminating at a first level in the outlet face of the block and one or more additional perforations terminating in the outlet face at a second level below or above the first level. The assembly includes at least two, and preferably at least three, main and auxiliary injectors for delivering and injecting gaseous fuel into the combustion zone. Each of the main injectors forms a pair with one of the auxiliary injectors. According to one embodiment, each of the main injectors surrounds one of the auxiliary injectors. According to a preferred embodiment, each of the auxiliary injectors surrounds one of the main injectors. The pairs (e.g., triplets) are positioned in the one or more first perforations that terminate at a first level. The combustor further includes a plurality of additional injectors for delivering and injecting oxidant into the combustion zone. The additional injectors are positioned in the one or more additional passages of the block to allow oxidant to be injected into the combustion zone above or below the gaseous fuel. The additional injectors may extend into a plane parallel to the plane of the main and auxiliary injectors of the pairs. According to another embodiment, the additional injector may define an injection plane for the oxidant that intersects the planes of the pairs in the combustion zone downstream of the outlet face, where the oxidant injected by the additional injector mixes and reacts with the fuel injected by the pairs.

As already indicated above, further injectors, in particular one or more injectors in addition to the main injector and the auxiliary injector of the pair, may be present in or around either of the main injector and the auxiliary injector of the pair.

According to a first embodiment, the one or more additional channels terminate in the outlet face of the block above the one or more first channels. According to another embodiment, the one or more additional channels terminate in the outlet face of the block below the one or more first channels.

According to a third embodiment, the block comprises one or more additional channels ending in the outlet face at a level located above the first level, in which one or more additional channels at least two, preferably at least three, additional injectors for the oxidant are positioned; and one or more additional channels terminating in the outlet face of the block below the first level, in which one or more additional channels are also located at least two, preferably at least three, additional injectors for oxidant. This embodiment allows for the injection of oxidant into the combustion zone above, below, or both above and below the gaseous fuel, depending on the requirements of the method.

The invention also relates to a furnace comprising an internal combustion zone and equipped with at least one assembly according to the invention for injecting a gaseous comburent selected from a gaseous fuel and a gaseous oxidant into said combustion zone. As indicated above, the at least one assembly may form part of a burner according to the invention, in which case the furnace is equipped with at least one burner according to the invention.

The invention can be particularly advantageously carried out in a furnace selected from a furnace for manufacturing or heating glass or enamel, a furnace for manufacturing or recovering or heating metal, such as a rotary furnace, or a reverberatory furnace for aluminium, copper or lead, cast iron, steel or the like.

Another aspect of the invention is a combustion process wherein a gaseous comburent selected from the group consisting of gaseous fuels and oxidizers is injected into the combustion zone by means of an assembly according to the invention, said assembly being able to form part of a burner according to the invention.

According to the method, the pressure detector of each assembly detects the gas pressure or the change in the gas pressure in the chamber of the assembly, the system for adjusting the assembly adjusts the flow cross section of the at least one auxiliary channel of the assembly, and the control system controls the adjustment system such that the flow cross section of the at least one auxiliary channel of each assembly is adjusted according to the pressure or the change in the pressure detected by the pressure detector of the assembly.

As described above, in the context of the apparatus and furnace according to the invention, in the case of a plurality of assemblies used in the method, each assembly may have its own control system connected to the pressure detector and to the regulating system, wherein the control system controls the regulating system such that the flow cross section of the at least one auxiliary channel is regulated as a function of the pressure or pressure variation detected by the pressure detector of said assembly. However, in a generally advantageous manner, the common control system may control the system for regulating each component in dependence on the pressure or pressure variation detected by the pressure detector of the relevant component.

As already indicated above, the system for adjusting the assembly may be controlled such that the gas pressure in the chamber of the assembly is within a predetermined pressure zone, or even such that the gas pressure in the chamber of the assembly corresponds to a predetermined value.

The gaseous comburent injected into the combustion zone by the assembly is a gaseous fuel selected from natural gas, biogas, propane, butane, residual gases of steel or methane reforming processes, hydrogen, or any mixture of the aforementioned gases, or is a gaseous oxidant, preferably a gaseous oxidant having an oxygen content of 21 to 100 vol%, preferably more than 21 vol%, in particular at least 80 vol%, more preferably at least 90 vol%.

The method according to the invention is particularly suitable for producing combustion in a combustion zone in the context of methods such as the manufacture or recycling of glass or enamel, the manufacture or recycling or heating of metals (e.g. aluminium, copper, lead, cast iron, steel, etc.).

The invention and its advantages will be better understood from the following examples: (refer to fig. 1 to 5) in which:

figure 1 schematically shows an assembly comprising a main injector (21) and a concentric auxiliary injector (22), the auxiliary injector (22) surrounding the main injector (21);

figure 2 schematically shows an assembly comprising a main injector (21) and a concentric auxiliary injector (22), the main injector (21) surrounding the auxiliary injector (22);

FIG. 3 schematically shows an assembly comprising a main injector (21) and a non-concentric auxiliary injector (22) at a distance;

figures 4 and 5 schematically show two views of an assembly incorporated in a burner for injecting a gaseous combustion agent into a combustion zone (1).

Fig. 1, 2 and 3 show the fluid inlet chamber (11). The main injector (21) is fluidly connected to the chamber (11) through a main channel (23). The auxiliary injector is fluidly connected to the chamber (11) by an auxiliary passage (24). The auxiliary channel (24) has an adjustable flow cross-section. The regulating system (32) allows this flow section of the auxiliary channel (24) to be regulated by means of a valve (33).

Fig. 1, 2 and 3 also show a pressure detector (30) for detecting the gas pressure or a change in the gas pressure in the chamber (11), and a control system (31) connected to the pressure detector (30). The control system is also connected to and controls the regulating system (32).

Fig. 4 schematically shows an assembly comprising three main injectors (21), each surrounded by its concentric auxiliary injector (22), and a chamber (11).

The main injector (21) is fluidly connected to the chamber (11) through a main channel (23). The auxiliary injector (22) is fluidly connected to the chamber (11) through an auxiliary passage (24). The auxiliary channel has an adjustable flow cross-section. The regulating system (32) allows this flow section of the auxiliary channel (24) to be regulated by means of a valve (33). There is a pressure detector (30) for detecting a pressure or gas pressure change in the chamber (11). The control system (31) is connected to the pressure detector (30). The control system is also connected to and controls the regulating system (32).

In fig. 4 and 5, the burner comprises a block (40) having an inlet face (41) and an outlet face (42) opposite the inlet face, and an additional injector (50) for injecting an additional fluid into the combustion zone (1).

The automatic adjustment by the feedback system according to the invention can advantageously be implemented in various combustion methods, such as for glass production.

Glass production furnaces mainly use air preheated to above 1000 ℃ as the oxidant. This hot air is obtained by passing through a regenerator (refractory brick pile). The amount of oxidant injected into the furnace at this temperature level involves a large amount of movement.

During furnace operation, production may need to be increased beyond the capacity of the regenerator, which cannot provide a larger amount of hot air due to fan suction limitations. Similar problems arise when the condition of the brick does not allow or no longer allows the desired preheating temperature to be obtained.

A burner device (oxy-burner) operating with an oxygen-rich oxidant then appears to be a particularly suitable solution. These burners are typically installed in available openings near the regenerator. In the case where oxy-combustion (i.e., combustion with an oxidant containing at least 80 vol%, and preferably at least 90 vol% of oxygen) produces smoke in an amount 4 times lower than that of air combustion, and has at least equal efficiency, the flame originating from the oxy-burner (hereinafter referred to as "oxy-flame") is severely interrupted by the flame originating from the regenerator operated with hot air (referred to as "air-flame"), because the amount of movement of the oxy-flame is low. These interruptions may cause the oxygen flame to interfere with the molten solid and unburned materials and thus cause glass quality or energy efficiency problems. These problems are even more pronounced when the power of the oxy-burner (and therefore the flow rate of the comburent substance) is reduced for lower, increased production phases. Therefore, it is critical to maximize the pulse or momentum of the oxygen flame over the entire power range of the oxy-burner.

Systems such as those described in document EP 2143999 allow the flow rate of the gaseous fuel to be adjusted manually between the two injections (primary and secondary) in order to maximize the pulsation of the fuel and thus ensure the stability of the flame of the oxy-burner. However, these manual systems require continuous adjustments of the fluid distribution by the operator and do not allow easy assessment of the impact of these adjustments on the process in real time. To avoid these adjustments and any quality problems, operators most often adjust the power of the air burner (regenerator), resulting in excessive oxygen consumption and increased production costs.

In this case, the invention can be advantageously used by defining a predefined pressure range or predefined pressure, allowing to ensure an automatic distribution of the flow between the main injection and the auxiliary injection, so as to maximize the pulse of the oxygen flame independently of the total flow of fuel.

For example, in the case of a 4% increase in production, the power of the oxy-burner may be 800kW, while for an 8% increase in oxygen, the power of the oxy-burner may be 1.8 MW. It has been determined that a pressure of 300 mbar in the distribution chamber between these two fuel injections allows providing a very stable flame at 800kW and 1800 kW. According to the invention, the automatic adjustment of the fuel distribution as a function of the gas pressure in the chamber upon power change will therefore allow optimizing production costs, limiting quality defects and optimizing energy consumption.

Claims

1. An assembly for injecting a gaseous combustion agent selected from a gaseous fuel and a gaseous oxidant into a combustion zone, the assembly comprising:

a chamber (11) having an inlet through which the agent is introduced into the assembly;

-at least one main injector (21) for conveying a main flow of the agent from the chamber (11) towards the combustion zone (1) and for injecting said main flow into the combustion zone (1), said at least one main injector being fluidly connected to the chamber (11) by at least one main channel (23);

-at least one auxiliary injector (22) for conveying an auxiliary flow of the agent from the chamber (11) towards the combustion zone (1) and for injecting said auxiliary flow into the combustion zone, said at least one auxiliary injector being fluidly connected to the chamber by at least one auxiliary channel (24);

the assembly further comprises:

a pressure detector (30) for detecting the gas pressure or gas pressure change in the chamber;

-a regulation system (31) for regulating the flow section of the at least one auxiliary channel; and

a control system (32) connected to the pressure detector and to the regulation system, the control system controlling the regulation system such that the flow cross section of the at least one auxiliary channel is regulated as a function of the pressure or the pressure variation detected by the pressure detector.

2. The assembly of claim 1, wherein the control system controls the regulation system such that the gas pressure in the chamber is in a predetermined pressure zone or such that the gas pressure in the chamber corresponds to a value predetermined by adjusting the flow cross section of the at least one auxiliary channel.

3. The assembly as claimed in any one of the preceding claims, wherein the regulating system is provided with at least one valve (33) which is capable of regulating the flow cross-section of the at least one auxiliary channel.

4. The assembly of any one of the preceding claims, comprising: at least one pair of a main injector and an auxiliary injector, wherein one pair of the main injector and the auxiliary injector surrounds the other pair of the main injector and the auxiliary injector.

5. The assembly of any one of the preceding claims, comprising: at least two main injectors and/or at least two auxiliary injectors, preferably at least two main injectors and at least two auxiliary injectors.

6. A device comprising a plurality of assemblies as claimed in any preceding claim, the device preferably comprising: a common control system connected to the pressure detector of each module and capable of controlling the regulation system of each module as a function of the gas pressure or the change in gas pressure detected by the pressure detector of said module.

7. A burner, comprising: an assembly of any one of claims 1 to 6 for injecting a gaseous combustion agent selected from gaseous fuel and gaseous oxidant into a combustion zone; and at least one additional injector for injecting additional fluid into the combustion zone.

8. The burner of claim 7, comprising: a block (40) having an inlet face (41) and an outlet face (42) opposite the inlet face (41), in the combustor, the assembly is attached to the inlet face (41) of the block (40) such that injectors of the combustor are positioned in one or more perforations through the block from the inlet face to the outlet face.

9. A burner as claimed in claim 8, wherein the main and auxiliary injectors of the assembly form pairs of main and auxiliary injectors, the pairs being positioned in at least one first perforation of the block (40) and the at least one additional injector being positioned in at least one additional perforation of the block (40).

10. The burner of claim 9, comprising: at least two pairs and at least two additional injectors, wherein the pairs define a first injection plane for the fluid, and wherein the injectors define a second injection plane for the additional fluid different from the first plane, the second plane being parallel to the first plane or oriented to intersect the first plane in the combustion zone downstream of the outlet face (42).

11. A furnace comprising an internal combustion zone and comprising at least one assembly as claimed in any one of claims 1 to 5 for injecting a gaseous combustion agent selected from gaseous fuel and gaseous oxidant into the internal combustion zone of the furnace, the at least one assembly optionally forming part of a burner as claimed in any one of claims 7 to 10.

12. The oven of claim 11, comprising: a plurality of modules, the furnace preferably comprising a common control system connected to the pressure detector of each module and capable of controlling the regulation system of each module as a function of the gas pressure or the change in gas pressure detected by the pressure detector of said module.

13. A method of combustion in which a gaseous combustion agent selected from a gaseous fuel and an oxidant is injected into an internal combustion zone by an assembly as claimed in any one of claims 1 to 5, optionally forming part of a burner as claimed in any one of claims 7 to 10, in which method:

the pressure detector of the assembly detects the gas pressure in the chamber of the assembly;

the system for adjusting the assembly adjusts the flow section of the at least one auxiliary channel; and

the system for controlling the assembly controls the system for adjusting the assembly such that the flow cross section of the at least one auxiliary channel is adjusted in dependence on the pressure or the pressure change detected by the pressure detector of the assembly.

14. The method of claim 13, wherein the control system controls the regulation system such that the gas pressure in the chamber is at a predetermined pressure zone or such that the gas pressure in the chamber of the assembly corresponds to a value predetermined by regulating the flow cross section of the at least one auxiliary channel of the assembly.

15. The method of one of claims 13 and 14, wherein the gaseous combustible substance is a gaseous fuel selected from natural gas, biogas, propane, butane, residual gas from steel or methane reforming processes, hydrogen, or any mixture of at least two of these gaseous fuels; or a gaseous oxidant having an oxygen content of 21 to 100 vol%, preferably more than 21 vol%, and in particular at least 80 vol%, more preferably at least 90 vol%.