WO2024208976A1

WO2024208976A1 - Improved burner and process for burning a waste stream

Info

Publication number: WO2024208976A1
Application number: PCT/EP2024/059203
Authority: WO
Inventors: Cosmin KATONA; Simon Willems; Hans HOOYBERGHS; Marcel Goemans
Original assignee: Tialoc Belgium Nv
Priority date: 2023-04-06
Filing date: 2024-04-04
Publication date: 2024-10-10
Also published as: BE1031488A1; BE1031488B1

Abstract

The disclosure herein relates to a system for burning a waste stream, said system comprising a precombustion chamber 100 and a burner module 200, said precombustion chamber housing a burn zone BZ arranged downstream of the burner module. A fuel stream, a first air stream and the waste stream are delivered into the burn zone of the precombustion chamber. The waste stream channel is provided with obstruction elements for partially obstructing the waste stream to create a disturbed flow wherein the waste stream channel is configured such that the disturbed flow of the waste stream is delivered into the burn zone of the precombustion chamber.

Description

IMPROVED BURNER AND PROCESS FOR BURNING A WASTE STREAM

FIELD

The present invention relates to the technical field of systems for burning waste streams, in particular for industrial use, more in particular for use as an industrial burner. The invention further relates to a process of burning matter and the use thereof to generate heat.

BACKGROUND

The industry has been using systems for burning waste for several years now. In known systems, the waste stream is fed to a combustion chamber wherein the waste is burned together with a fuel stream and an airstream. The streams are fed to the combustion chamber via a burner module placed in front, the combustion chamber can have a front chamber and a back chamber.

Careful control of the burn reaction within the combustion chamber is needed for reasons of safety, economy and environment. The burn reaction should be controlled to avoid thermal damage to the chamber inner walls and emissions should be kept low.

Even though, burners have been deployed for over several years, there is still a need for improvement since the conventional burning systems may still suffer from thermal damage to the chamber walls and/or have burn reactions causing high emissions, such as NOx emissions. The thermal damage can occur as a result of hot spots if flow patterns of streams injected in the chamber are not well conceived.

SUMMARY OF THE INVENTION

It is an object of embodiments of the invention to provide a system for burning waste with reduced thermal damage and/or reduced emissions.

Thereto the inventors have provided a system according to claim 1. The system has a precombustion chamber and a burner module. The precombustion chamber houses a burn zone arranged downstream of the burner module. The burner module has a fuel stream channel, a first air channel and a waste stream channel. Said channels being configured to respectively deliver a fuel stream, a first airstream and the waste stream into the burn zone of the precombustion chamber.

The waste stream channel is provided with obstruction elements configured for partially obstructing the waste stream to create a disturbed flow of the waste stream downstream of said obstruction elements. The disturbed flow downstream of said obstruction elements is more turbulent than a flow of the waste stream upstream of the obstruction elements. The waste stream channel is configured such that the disturbed flow of the waste stream is delivered into the burn zone of the precombustion chamber.

The invention is based on the understanding that by having the obstruction elements configured for partially obstructing the waste stream to create the disturbed flow and having the disturbed flow delivered into the burn zone of the precombustion chamber a system for burning with reduced thermal damage and/or reduced emissions can be achieved. Several benefits can be achieved by the system, including and not limited thereto: avoidance of thermal damage, reduced emissions such as NOx emissions, improved burning behavior within the combustion chamber (precombustion and/or combustion), improved safety and a reduced need for maintenance.

Testing and simulations have shown that chances of hot spots are reduced by including the obstruction elements. Surprisingly, thermal damage, especially to the walls of the precombustion chamber, could be reduced or avoided. As a result, safety and operation time of the system is improved. In standard flow patterns, a dominant flow can take over and create hot spots on the inner wall. This dominant flow is also called a “preference flow pattern”, the present system has the benefit of a reduced or neutralized preference of the waste stream towards a side wall of the precombustion chamber. It was further found that more intensity in the turbulence could be achieved which benefits the burn reaction within the (pre)combustion chamber. Thereby, a more efficient burning reaction could be achieved which benefits lower emissions.

Preferably, the burner module extends along a longitudinal axis wherein the waste stream is fed to the waste stream channel of the burner module via a waste stream inlet angularly positioned with respect to the longitudinal axis of the burner module. Preferably the waste stream inlet has an inlet angle P chosen from any angle between about 30° to about 90°, such as 45° or 90°. Most preferably the inlet angle is about 90°. As such, dominant behavior of a particular flow could be avoided. Furthermore, such angular positioning of the waste stream inlet allows a longitudinal dimension of the burner module to be reduced. In this manner, spatial efficiency of the system within the available space e.g. of an industrial plant could thereby be improved.

Preferably, the waste stream channel is delimited by a first and second wall extending in longitudinal direction of the burner module. The obstruction elements preferably extend between the first and second wall. The first and second wall can be an inner wall and an outer wall, respectively, in case the burner module is designed in cylindrical configuration (as explained further).

The obstruction elements preferably extend from the first wall in the direction of the second wall. Such extension of the obstruction elements may facilitate system manufacturing.

The obstruction elements preferably extend substantially perpendicularly between the first wall and the second wall. This way a desired waste stream disturbance is achieved in an efficient manner.

The first and second wall of the waste stream channel may be spaced apart by a spacing distance h. The obstruction elements then preferably extend over at least 30 % of the spacing distance h, preferably at least 50 % of the spacing distance h, more preferably at least 75 % of the spacing distance h. This allows assurance of waste stream disturbance to be improved.

In an embodiment, the obstruction elements do not fully extend between the first and second wall. In other words, the obstruction elements do not form a connection between the first and second wall. Such partial extension of the elements can benefit pressure drop and may benefit stability, in particular for low flows. The elements preferably extend over 30 - 95 % of the spacing distance h.

In another embodiment, one or more of the obstruction elements form a connection between the first and second wall of the waste stream channel. In such a case, the extension of the obstruction elements over the spacing distance h between the first and second wall is 100 %. By forming a connection, a desired disturbance can be achieved. Additionally, more mechanical stability may be created within the system.

Advantageously the system may further have a waste stream inlet. The waste stream channel preferably extends from the waste stream inlet to the precombustion chamber over a distance L2. The distance L2 thus being measured between the precombustion chamber and the waste stream inlet. It preferred that the obstruction elements closest to the waste stream inlet are positioned a distance di therefrom.

Preferably, distance di is more than 50 % of distance L2 such that the obstruction elements closest to the waste stream inlet are closer to the precombustion chamber than to the inlet of the waste stream. Preferably, the distance di is less than 1 meter, more preferably between 0.1 m and 1 m, such as between 0.2 and 1 m. The arrangement and choice of distance di promotes dissipation of created vortexes throughout the waste stream channel, such dissipation facilitates to achieve a desired waste stream disturbance.

Preferably, the obstruction elements comprise one or more rows of obstruction elements arranged perpendicular to a longitudinal axis of the waste stream channel. Having one or more rows of obstruction elements extending perpendicular to the longitudinal axis is beneficial to have the waste stream disturbed as desired. Preferably, multiple rows are present to promote achievement of a good disturbance. A good disturbance promotes reduction of thermal hotspots in the downstream combustion chamber. Preferably, the one or more rows of obstruction elements are arranged on a circumference of a circle having the longitudinal axis going through the centre line of the circle. The circle in this respect is substantially circularly shaped, oval shapes may also be possible.

More preferably, obstruction elements within a same row of the one or more rows are substantially symmetrically arranged around or with respect to the longitudinal axis of the waste stream channel. Having a symmetrical arrangement may benefit flow disturbance and/or may benefit system manufacturing.

Preferably, a plurality of the obstruction elements are arranged in a same row such that at least one, preferably at least two, more preferably at least three obstruction elements are present per 45 °- segment around the longitudinal axis of the waste stream channel. By having obstruction elements within the same row to be arranged around the axis in this manner, achievement of a desired disturbance of the stream within the respective channel is promoted.

Preferably, the obstruction elements comprise a first row of obstruction elements and a second row of obstruction elements. The first row is positioned upstream from the second row of obstruction elements. Further rows, such as a third and a fourth may be present. Preferably, the first row and second row (and optionally the further rows) of the obstruction elements are positioned in a staggered arrangement relative to each other. The staggered arrangement causes possible vortexes created by the upstream row to be broken down by the downstream row and reduces the chance that a frequency is formed which can overlap with the sound power level of the combustion. Thus, by having the rows arranged in a staggered or alternating manner, thermo-acoustic instability is reduced.

Preferably, the obstruction elements are arranged in rows within the waste stream channel such that at least one row of obstruction elements is present per meter of waste stream channel. This distribution of rows promotes achievement of a desired disturbance of the stream within the respective channel. The obstruction elements are preferably positioned at a distance dm of the precombustion chamber, wherein said distance dm is at least 150 mm, such as around 220 mm. This way, the flow is injected in the chamber with a good disturbance.

Preferably, the obstruction elements are elongated elements, preferably elongated elements extending substantially perpendicular to and away from the longitudinal axis of the burner module. Such elongation promotes a good disturbance of the stream within the respective channel.

Preferably, the obstruction elements include at least 4, preferably at least 8 elements which are substantially symmetrically arranged around the longitudinal axis of the burner module. This way, a good disturbance of the stream within the respective channel is achieved.

One or more elements of the obstruction elements within the waste stream channel can have a 3D shape chosen from: a substantially cylindrical shape, a cone shape, a prism shape such as triangular prism shape, square prism shape, pentagonal prism shape, rectangular prism shape, hexagonal prism shape or trapezoidal prism shape, a cuboid shape, a rectangular shape, a sphere shape, a pyramid shape. Preferably, the 3D shape is cylindrical, cuboid, rectangular or prism. The shapes have been found to disturb the flow of the stream within the respective channel in a way beneficial to achieve the improvements such as a disturbance causing a reduction in thermal hotspots, improving safety, the achievement of a better burn reaction such that emissions may be reduced.

Preferably, one or more elements of the obstruction elements within the waste stream channel have a cross section, when viewed in a direction perpendicular to the longitudinal axis of the burner module, shaped as a polygon, preferably a regular polygon, said shape preferably being chosen from a triangle, a square, a pentagon, a hexagon or shaped as a substantially circular shape. More so, one or more of the obstruction elements are preferably oriented within the waste stream channel such that an angle of the polygon is oriented towards an upstream direction of the waste stream, more in particular an upstream direction along the longitudinal axis of the waste stream channel. Surprisingly, it was noticed that in this orientation the turbulence after the obstructions are more narrowed in the downstream direction meaning that detached eddies are smaller and downstream flows gain less fluctuations. With other words, the orientation promotes a good disturbance of the stream within the respective channel which is beneficial for the burn reaction in the downstream combustion chamber. The system may further have a second airstream channel. The second airstream channel is configured to deliver a noncombustible stream into the precombustion chamber. It should be understood that the second airstream channel is not limited to channel an airstream alone. Any noncombustible stream can be received and delivered into the precombustion chamber via the second airstream channel. Examples of noncombustible streams are: air, steam, argon or N2 gas or any gas or stream that has a low heating value or mixtures thereof. The second airstream may be used for cooling effects or as a mixing path for non-combustible streams.

The precombustion chamber preferably comprises at least one side wall housing the burn zone. The second airstream channel is preferably arranged to deliver the noncombustible stream between the burn zone and the side walls of the precombustion chamber to create a barrier zone with the noncombustible stream, such as an air barrier zone, for protecting the side walls from burn reactions occurring in the burn zone. This way, safety of the system is improved and the need for maintenance or replacement of system elements over time can be reduced.

The second airstream channel may have airstream obstruction elements. More in particular, the second airstream channel of the burner module is preferably provided with airstream obstruction elements configured for partially obstructing the noncombustible stream such that a turbulent flow of noncombustible stream is delivered to the precombustion chamber.

The “waste stream obstruction elements” may also be referred to herein as “the first disturbers”.

The “airstream obstruction elements” may also be referred to herein as “the second disturbers”.

The second disturbers may be deployed within the system in addition to the first disturbers or may be deployed in a system without the first disturbers, such as: a system for burning a waste stream, said system comprising a precombustion chamber and a burner module, said precombustion chamber housing a burn zone arranged downstream of the burner module, said burner module comprising a fuel stream channel, a first air channel and a waste stream channel, a second airstream channel, being configured to respectively deliver a fuel stream, a first airstream, the waste stream and a noncombustible stream, such as a second airstream into the burn zone of the precombustion chamber; wherein the second airstream channel is provided with the airstream elements configured for partially obstructing the noncombustible stream to create a disturbed flow of the noncombustible stream downstream of said obstruction elements, wherein said disturbed flow downstream of said obstruction elements is more turbulent than a flow of the waste stream upstream of the obstruction elements; and wherein the waste stream channel is configured such that the disturbed flow of the noncombustible stream is delivered into the burn zone of the precombustion chamber.

By having the airstream obstruction elements within the system, improved effects can be achieved. The improved effects include reduced thermal damage and/or reduced emissions, in particular if the airstream obstruction elements (second disturbers) in the second airstream channel are combined with the waste stream obstruction elements (first disturbers) in the waste stream.

The second airstream channel may be delimited by a first and second airstream channel wall, such as an outer and an inner airstream channel wall, extending in longitudinal direction of the burner module and wherein the airstream obstruction elements extend between the first and second wall. The first and second wall of the airstream channel typically have a spacing distance h’ in between. The airstream obstruction elements preferably extend over at least 30 % of the spacing distance h’, preferably at least 50 %, more preferably at least 75 % such that the obstruction elements partially or fully extend between the first and second airstream channel walls. The same or similar effects can be achieved as explained above in connection to spacing distance h between the first wall and second wall of the waste stream channel. Preferably, the one or more of the airstream obstruction elements (second disturbers) form a connection between the first and second wall of the airstream channel.

The airstream obstruction elements (second disturbers) within the second airstream channel preferably has one or more of the following features:

- comprise one or more rows arranged in a row around a longitudinal axis of the second airstream channel, preferably such that airstream obstruction elements within a same row of the one or more rows are symmetrically arranged around the longitudinal axis of the second airstream channel;

- a plurality of the airstream obstruction elements are arranged in a same row such that at least 1 obstruction element is present per 45° segment around the longitudinal axis of the airstream channel;

- comprise a first row of airstream obstruction elements and a second row of obstruction elements, wherein the first row is positioned upstream from the second row in the second air stream channel and wherein said rows are preferably arranged in staggered arrangement relative to each other;

- being arranged in rows within the second airstream channel such that at least one row of obstruction elements is present per meter of airstream channel;

- being positioned at a distance dm2 of the precombustion chamber, wherein dm2 is at least of 150 mm, such as 400 mm;

- comprising at least 4, preferably at least 8 elements which are substantially symmetrically arranged around the longitudinal axis of the second air stream channel;

- are elongated elements, preferably elongated elements extending substantially perpendicular to and away from the longitudinal axis of the second air stream channel;

- have a shape chosen from: a substantially cylindrical shape, a cone shape, a prism shape such as triangular prism shape, square prism shape, pentagonal prism shape, rectangular prism shape, hexagonal prism shape or trapezoidal prism shape, a cuboid shape, a rectangular shape, a sphere shape, a pyramid shape;

- have a cross section shaped as a polygon, said shape preferably being chosen from a triangle, a square, a pentagon, a hexagon; preferably wherein one or more of the obstruction elements is oriented within the airstream channel such that an angle of the polygon is oriented towards an upstream direction of the waste stream.

It is to be readily recognized that same or similar effects and benefits can be achieved with the features in connection to the airstream obstruction elements (second disturbers) as with the corresponding features explained in connection to the waste stream obstruction elements (first disturbers). The second disturbers may have the same or similar features as the first disturbers.

The system may further have a gas lance. More in particular, the burner module may comprise a gas lance to deliver the fuel stream to the burn zone of the precombustion chamber. Preferably, the waste stream channel is arranged at least partially around the gas lance, preferably substantially entirely around the gas lance in a mantle wise fashion.

The outer wall of the gas lance is then faced towards the inner wall of the waste stream channel. This way, the gas lance is arranged to inject fuel in the centre of the burn zone while the waste stream channel is arranged to inject the waste stream directly adjacent (and preferably towards) the centre of the burn zone. This arrangement has been found beneficial to promote a good burning behavior in the burn zone.

Preferably, the burner module further comprises a second fuel stream channel arranged for delivering a second fuel stream to the burn zone. The fuel stream (may now also be referred to as the first fuel stream) containing a first fuel, the second fuel stream containing a second fuel. The second fuel is preferably a H2-fuel. This way, fuel injection into the burn zone can be regulated such that undesired emissions such as thermal NOx emissions can be reduced. In a particular preferred embodiment, the second fuel stream channel is arranged to inject the second fuel stream in the centre of the burn zone. More preferably, while the first fuel stream channel is arranged to inject the first fuel stream directly adjacent said centre and preferably around said centre. The burner module may comprise several housings, preferably the housings are substantially cylindrical. The burner module may have an inner combustion air housing and a waste gas housing.

The inner combustion air housing is configured for receiving the first airstream.

The waste gas housing is configured for receiving the waste stream.

The burner module preferably further comprises an outer combustion air housing for receiving the noncombustible stream, such as a second airstream.

Preferably, the waste stream obstruction elements (first disturbers) within the waste stream channel are arranged and extend between the inner combustion air housing and the waste gas housing, preferably such that the obstruction elements connect the inner combustion air housing and the waste gas housing. Preferably, the airstream obstruction elements (second disturbers) are arranged and extend between the waste gas housing and the outer combustion air housings. By having the elements to connect the housings, a desired disturbance of the respective flow within the channel can be achieved.

The system may further be provided with blades. More in particular, the first airstream channel of the burner module is provided with one or more blades configured to modify the flow of the first airstream such that the first airstream is delivered to the burn zone in a swirled fashion. This way, improved burning behavior can be achieved. The improved burning behavior is believed to be a result of improved mixing since the swirls are key for mixing while staying efficient and keep the burn in a short distance and attached to the respective injection head.

The precombustion chamber may have side walls. Preferably side walls with an angled part adjacent the burner module, wherein said angled part of the side walls extends under an angle a with respect to the longitudinal axis of the burner module, said angle a being between 10 -75°, preferably between 10 - 70°. This way, chances of creating (undesired) dead zones (also referred to as recirculation) are reduced. Dead zones reduce efficiency of the burn reaction and should be avoided. The system may further have means for controlling a flow ratio of the first airstream / a noncombustible stream (such as a second airstream) into the precombustion chamber. By having such a means, the burning reaction within the chamber can be manipulated as desired.

The first airstream can be fed to the first air channel of the burner module via a first airstream inlet angularly positioned with respect to the longitudinal axis. The fuel stream may be fed to the fuel stream channel of the burner module via a fuel stream inlet angularly positioned with respect to the longitudinal axis. Hence, the inlet is not parallel to the longitudinal axis. Preferably, one or both inlet(s) is/are arranged substantially perpendicular to the longitudinal axis of the burner module.

Typically, the longitudinal axis of the combustion chamber extends in the same direction or is the same as the longitudinal axis of the burner module.

Preferably, one or more, preferably all, of the fuel stream, the first airstream and the waste stream is or are fed to a respective channel of the burner module via an inlet angle between 0° - 60°, preferably between 10° - 60°, more preferably between 25° - 50°, such as 30° or 45°.

A further aspect of the invention relates to a process of burning matter, said process comprising the steps of:

- delivering a fuel stream, a first airstream and a waste stream into a burn zone of a precombustion chamber such that the streams feed a burn reaction to burn matter;

- disturbing the waste stream before the waste stream is being entered into the precombustion chamber via obstruction elements (first disturbers) such that a disturbed flow of waste stream is created downstream of the obstruction elements;

- delivering the disturbed flow of the waste stream into the burn zone of the precombustion chamber.

The aspect is based on the inventive insight that by disturbing the waste stream before the waste stream is being entered into the precombustion chamber via obstruction elements and by delivering the disturbed flow of the waste stream into the burn zone of the precombustion chamber several benefits could be achieved. These benefits include and are not limited to a reduced thermal damage and/or reduced emissions. By having the disturbed flow of the waste stream delivered into the burn zone, an improved burn reaction therein can be achieved. Further, improved safety and a reduced need for maintenance can be achieved. Preferably, the process further comprises:

- delivering a noncombustible stream, such as second airstream, into the precombustion chamber;

- disturbing the noncombustible stream before the noncombustible stream is being entered into the precombustion chamber with airstream obstruction elements (second disturbers) such that a disturbed flow of second airstream is created;

- delivering the disturbed flow of the second air stream into the burn zone of the precombustion chamber such that an barrier zone (for example an air barrier zone) for protecting the side walls from burn reactions within the burn zone is created. This way, safety and reduced need for maintenance can be achieved.

Preferably the process comprises the step of: a first fuel being delivered via the fuel stream to the burn zone, and wherein a second fuel, different from the first fuel, is delivered via a second fuel stream, said second fuel being a H2 fuel, such as H2-gas. This step may be deployed in a process without the disturbing step, although preferred together. By having the first fuel and the second fuel different and being an H2 fuel, NOx emissions where found to be improved.

Typically, the first fuel is a carbon containing fuel, preferably a hydrocarbon fuel and/or natural gas. By having the H2 fuel entering the burn zone together with the first fuel, consumption of the first fuel could be reduced. More so, surprisingly, NOx emissions dropped significantly.

In a particular embodiment, the first fuel is chosen from: natural gas (optionally processed), methane, ethane, propane and the like or mixtures thereof.

More preferably, the first and second fuel are delivered into the burn zone such that a 5 - 40 % fraction, preferably 5 - 20 %, more preferably 5 - 15 %, most preferably 5 - 10 % of the total mass flow of both the first and second fuel delivered into the burn zone consists of the second fuel being the H2 fuel. In these ranges, it was found that thermal NOx could be reduced significantly.

A further aspect relates to the use of the system and/or process as described herein for the generation of heat. Such use has the benefit that thermal energy may be created for reduced by with reduced emissions and/or reduced thermal damage (resulting in increased safety and less need for replacement). Industrial heating commonly relies on a burner (or burner systems) for the heating and promotion of industrial processes. These processes are used in a wide variety of manufacturing industries, including automotive, major appliances, food and beverage, petrochemical, power, chemical, and more. BRIEF DESCRIPTION OF DRAWINGS

The invention will now be described with more details with respect to the figures illustrating some preferred embodiments.

Figure 1 shows a schematic side view of a system according to an embodiment.

Figure 2 shows a partial view of the system of figure 1.

Figure 3 shows a cross-sectional schematic view of an embodiment.

Figure 4 shows a cross-sectional schematic view of another embodiment.

Figure 5 shows an exploded view of a burner module according to an embodiment.

Figure 6 A shows a perspective view of a part of the burner module of figure 5.

Figure 6B illustrates schematically a staggered arrangement of obstruction elements.

Figure 7 shows a perspective view of a burner according to an embodiment.

Figure 8 shows possible shapes of obstruction elements.

Figure 9 shows another embodiment wherein two fuel channels are used.

Figure 10 shows a detailed perspective view a part of the burner module of figure 9.

Figure 11 shows a part of figure 10 as seen from inside the pre combustion chamber.

The skilled person will appreciate on the basis of the description that the invention can be embodied in different ways and on the basis of different principles. The invention is not limited to the described embodiments.

DETAILED DESCRIPTION

In the figures, elements indicated with the same reference number have the same technical features and effects.

The system 1

Precombustion chamber 100 side walls 101 of the precombustion chamber angled part 70

Burner module 200 longitudinal axis 201 of the burner module. a fuel stream channel 210 a second fuel stream channel 210b fuel inlet 211 a first air channel 220 blades 50 a waste stream channel 230 waste stream obstruction elements 30 (first disturbers) waste stream inlet 231 first wall 232 (inner wall) and second wall 233 (outer wall) of the waste stream channel spacing distance h between first and second wall a second airstream channel 240 waste stream inlet 241 airstream obstruction elements 40 (second disturbers) first wall 242 and the second wall 243 of the airstream channel spacing distance h’ between first and second wall an inner combustion air housing 2 a waste gas housing 3 an outer combustion air housing 4 a gas lance 5

Figure 1 shows an example of a system 1 for burning waste. The system has a precombustion chamber 100 and a burner module 200 arranged upstream of the precombustion chamber 100. A back combustion chamber 90 may be arranged further downstream of the precombustion chamber. The burner module has channels 210, 220, 230, 240 for delivering streams to the burn zone BZ of the precombustion chamber. Said channels of the burner module being the fuel stream channel 210, first air channel 220 and waste stream channel 230. The channels are configured to deliver the streams (fuel stream FS, airstream AS 1, waste stream WS) into a burn zone BZ of the precombustion chamber 100 (streams and burn zone BZ are shown in more detail in figure 2). The channels of the burner module can be arranged in any suitable manner as long as the streams are properly delivered to the burn zone. By combusting the waste stream, the fuel stream and the first airstream in the combustion chamber, heat can be generated. The amounts of the streams delivered to the burn zone can be regulated by any suitable control means.

The waste stream channel 230 is further provided with obstruction elements 30 (first disturbers). The obstruction elements 30 may be referred to herein as “waste stream disturbers” or “first disturbers” and these wordings can be used interchangeably. The obstruction elements 30 are arranged within the waste stream channel such that the flow within the waste stream is disturbed. More in particular, the obstruction elements 30 are arranged in a way such that the flow of the waste stream downstream of said obstruction elements is rendered more turbulent than the flow of waste stream upstream of the obstruction elements. The disturbed flow of the waste stream is then delivered into the burn zone BZ (illustrated in more detail in figure 2) of the precombustion chamber. Having the flow disturbed promotes burning behavior and can reduce preference flows which benefits the reduction of thermal hotspots.

Figure 1 further shows the longitudinal axis 201 of the burner module 200. The waste stream channel

230 extends in a direction along the longitudinal axis, typically in a direction parallel thereto. The waste stream WS is fed via inlet 231 to the waste stream channel 230, the inlet is preferably angularly positioned with respect to the longitudinal axis of the respective channel. The inlet angle of the inlet

231 is preferably 30° to about 90°, such as 45° or 90° (as shown in figure 1). The inlet angle of inlet 231 is shown in more detail figure 3 wherein the angle is indicated with beta .

The inlet angle can be measured between the incoming direction of flow coming out of the respective inlet and the longitudinal axis of the burner module or the longitudinal axis of respective stream. For example the angle of the flow out of inlet 231 and the longitudinal axis of the waste stream channel 230, which is typically the same axis or at least parallel to the longitudinal axis of the burner module 200. The inlet angle of the other inlets 211, 221, 231, 241 may be measured in the same way. The first airstream AS1 is preferably fed via inlet 221 to airstream channel 220 with an inlet angle of the inlet 221 preferably 30° to about 90°. A second airstream AS2 may be fed via inlet 241 to the second airstream channel 240. The second airstream channel 240 may be provided with second disturbers 40. A control means 6 may be present to regulate the ratio of AS1/AS2 coming into the burn zone, such regulation may be done manually or automatically based on a feedback signal from a sensor.

Figure 1 further shows that the obstruction elements 30 (first disturbers) arranged in a first row 30a and a second row 30b. The first row is positioned upstream from the second row. The first row 30a of obstruction elements closer to the waste stream inlet 231 is positioned at a distance di therefrom. Distance di is typically measured as the smallest distance between the closest element of the first row 30a and the inlet 231 measured, the smallest distance extending along a line parallel to the longitudinal axis of the burner module. Distance di is preferably at most 1 meter such that the vortexes are disturbed decently to achieve improved burning behavior within the combustion chamber. The second disturbers 40 may be arranged in a similar manner.

As far as can be seen, the obstruction elements 30 in the first row 30a and second row 30b are arranged symmetrically around the longitudinal axis of the waste stream channel 230. In figure 1, the longitudinal axis of the waste stream channel 230 extends in the center thereof and corresponds to the longitudinal axis 201 of the burner module 200. Obstruction elements 40 are arranged within the second airstream channel 240 in a first row 40a and second row 40b, the rows are arranged symmetrically around the longitudinal axis of the airstream channel 240. In figure 1 , the longitudinal axis of the airstream channel 240 extends in the center thereof and corresponds to the longitudinal axis 201 of the burner module 200.

The figure further shows that row 30a and row 30b have enough individual obstruction elements such that at least one obstruction element is present per 45 “-segment around the longitudinal axis of the waste stream channel 230. It is preferred that at least 2, more preferably at least 3, even more preferably at least 4 obstruction elements are present per 45 “-segment around the longitudinal axis of the waste stream channel so as to create a desired disturbance which benefits downstream burning behavior.

The first disturbers 30 are arranged in a first row 30a and a second row 30b. It is understandable that additional rows may be present. The second disturbers 40 may be arranged in a similar manner. For example, the second disturbers 40 can have first row 40a and a second row 40b. The second disturbers 40 may achieve similar benefits such as improved burning behavior, reduction of thermal hotspots, reduced need for replacement.

The rows are preferably arranged in staggered arrangement, as for example shown in figure 6A. Having the rows (e.g. rows of first and/or second disturbers, equally applicable) arranged in a staggered arrangement can reduce thermoacoustic instability. A principle of the staggered arrangement shall now be explained with figure 6B. Having rows 30a, 30b and/or rows 40a, 40b arranged in a staggered arrangement causes respective flow stream (indicated with arrow FLS) coming between adjacent elements 34u of the upstream row 30a, 40a to be disturbed and subsequently be disturbed again via impact with a downstream element 34d of the downstream row 30b, 40b. Said downstream element 34d is positioned downstream and preferably at least in between the two upstream elements as seen from a sideways view perpendicular to the respective flow direction.

As explained herein, at least one row of obstruction elements 30a is preferably present per meter of waste stream channel 230, typically per meter of distance (indicated with Lws) between inlet 231 and the end of the channel from which the respective stream is injected into the combustion chamber. The burner module 200 may further have an optional second airstream channel 240 for receiving and delivering a second airstream AS2 into the burn zone BZ. The second airstream channel is preferably arranged such that the second airstream is injected into the precombustion chamber between the burn zone BZ and the inner walls of the combustion chamber, such design has the benefit that an (air) barrier is created protecting the inner walls from high temperatures of the burn zone. This way, thermal damage to the inner walls can be reduced or avoided. The second airstream channel 240 may also be referred to as a channel for a non-combustion stream since any non-combustion gas could be delivered via channel 240. The second airstream channel is preferably provided with the second disturbers 40.

Figure 2 shall now be used to explain some principles of the improved burning behavior and flows within the precombustion chamber 100. Figure 2 corresponds with the burner system shown in figure 1 and shows burner module 200 and precombustion chamber 100 with more detail.

As schematically shown, burner module 200 is configured to receive several streams (the fuel stream FS, first airstream AS1 and waste stream WS). Module 200 is preferably further configured to receive a second airstream AS2. Notably, the second airstream can be any noncombustible stream. The streams are received by respective channels, being the fuel stream channel 210, first air channel 220, waste stream channel 230 and optionally the second airstream channel 240. The first disturbers 30 are arranged within the waste stream channel 230. The second disturbers 40, if present, are arranged in the second airstream channel 240.

The channels are arranged such that the respective streams are delivered into the precombustion chamber 100. The fuel channel 210 is configured to deliver the fuel stream FS to the burn zone. The system may further have a pilot light or electric ignition system (not shown) to start a burning reaction in the burn zone. The fuel channel may for example be comprised within a gas lance.

The first airstream channel 220 delivers the airstream AS1 to the burn zone, preferably after being manipulated by blades 50 arranged within channel 220 such that the airstream is delivered to the burn zone in a swirling fashion. The blades are configured to modify the flow of the first airstream such that the first airstream is delivered to the burn zone in a swirled fashion. An example of swirling behavior is illustrated by swirls SA.

The waste stream WS is injected into the burn zone BZ after being disturbed by the obstruction elements 30 (also called first disturbers). The disturbed waste stream is indicated with stream dWS. The second airstream AS2 is preferably injected into combustion chamber 100 between the burn zone

BZ and the inner side walls 101 of the combustion chamber 100.

The second airstream AS2 is preferably injected after being disturbed by obstruction elements 40 (second disturbers) arranged in the second airstream channel 240. The disturbed second airstream is indicated with stream dAS2. By having the airstream stream AS2 (or any other noncombustible stream) disturbed by the second disturbers 40, a more turbulent (air) flow is created downstream of the second disturbers which improves thermal protection of the (air) barrier zone AZ between the burn zone BZ and inner side walls 101 of the combustion chamber 100.

The first airstream channel 220 is typically arranged such that the first airstream AS1 is injected into the center of the burn zone BZ while the second airstream channel 240 (if present) is arranged to inject a second airstream between the burn zone Bl and the inner side walls 101 of the combustion chamber to form a barrier zone AZ in between.

Figure 3 shows a cross sectional side view of the burner module 200 and precombustion chamber 100. The flows of the streams WS, AS1, FS are indicated with arrows for illustrative purposes.

The streams are respectively received by the burner module 200 via waste stream inlet 31 , airstream inlet 41 and fuel stream inlet 10. More in particular, received by fuel stream channel 210, first air channel 220 and waste stream channel 230. Burner module 200 extends along a longitudinal axis 201. Channels 210, 220, 230 typically extend along an axis parallel to longitudinal axis 201 of the burner module. The channels 210, 220 and 230, preferably all channels, are arranged in a preferred cylindrical configuration such that they have the same longitudinal axis in their centre.

The waste stream WS is fed to the waste stream channel 230 of the burner module via waste stream inlet 231. Said inlet 231 is preferably angularly positioned with respect to longitudinal axis 201 of the burner module. The angular position is indicated with Greek letter p, preferably the inlet is arranged such that a flow thereof flows in the channel under an angle relative to a longitudinal axis of said channel, said angle preferably between 30° to about 90°, such as about 45° or about 90°.

The waste stream inlet 31 has an inlet angle preferably chosen from any angle between 30° to about 90°, such as 45° or 90°, such angle benefits use of space. The first airstream AS1 is fed via inlet 41, said inlet preferably having an inlet angle (not indicated) between 30° to about 90°. Such inlet angle of airstream AS1 benefits use of space. The fuel stream is fed via inlet 10, said inlet can have any suitable inlet angle (not indicated), preferably between 30° to about 90°.

The waste stream channel as shown in figure 3 is delimited by first and second wall, illustrated with inner wall 232 and an outer wall 234. The walls 231 , 232 typically extend parallel to the longitudinal axis 201 of the burner module 200. The obstruction elements 30 extend between the first wall 232 and second wall 234.

In principle, obstruction elements 30 can be arranged on any or both of the inner 232 and outer wall 234. Figure 3 shows an example wherein the obstruction elements 30 extend from the first wall in the direction of the second wall, this way the waste stream WS is obstructed and a downstream flow dWS with more turbulent behavior is created.

It is preferred that the obstruction elements 30 extend substantially perpendicularly between the first wall 232 and the second wall 233 to improve disturbance of the waste stream flow WS. Such improved disturbance can improve burning of the waste stream and avoid hotspots within combustion chamber 100.

Figure 3 further illustrates that the first wall 232 and second wall 232 of the waste stream channel 230 are spaced apart by a spacing distance h. It is preferred that the obstruction elements 30 (first disturbers) extend over at least 30 % of said spacing distance h, preferably at least 50 % of the spacing distance h, more preferably at least 75 % of the spacing distance h. This way, the waste stream is disturbed in an improved fashion.

As shown in figure 4, the second air stream channel 240 may (also) be delimited by a first wall 242 and second wall 243. The walls 242, 243 can be spaced apart by a spacing distance h’. It is preferred that the second disturbers 40 extend over at least 30 % of said spacing distance h’, preferably at least 50 % of the spacing distance h’, more preferably at least 75 % of the spacing distance h’.

Although not illustrated in figure 3, it is preferred that one or more, preferably most of the first disturbers 30 form a connection between the first wall 232 and the second wall 233 of the waste stream channel 230. In such a case, obstruction elements would extend over 100 % of the spacing distance h. The second disturbers 40 may be arranged so as to extend in a similar manner. Figure 3 further shows that the obstruction element 30 within the waste stream channel 230 most near waste stream inlet 231 is positioned at a distance di therefrom. Distance di is preferably more than 50 % of distance L2 such that the obstruction element 30 most near the waste stream inlet are closer to the precombustion chamber than to the inlet of the waste stream. This way, improved burning behavior can be achieved which can facilitate achieving lower emissions, improving efficiency and/or achieving an increased safety.

Figure 3 further shows that the first disturber 30 most near inlet 231 is positioned at a distance di therefrom wherein said distance di is measured as the smallest distance between the closest first disturber 30 and the inlet 23, whereby the smallest distance extends along a line parallel to the longitudinal axis of the burner module. Surprisingly, having a distance di of at most 1 meter resulted in a good flow disturbance which benefits burning behavior.

Figure 3 further shows that obstruction elements 30 may be positioned at a distance dm of the precombustion chamber 100. Distance dm is preferably at least of 150 mm, such as around 220 mm. Distance dm can be measured between the end of channel 230 from which the disturbed waste stream dWs is injected into the burn zone BZ and the obstruction element 30 positioned most closely to said end. The distance dm is measured as the smallest distance extending along a line parallel to the longitudinal axis of the waste stream channel 230.

As explained above in connection to figure 1, the obstruction elements 30 can be arranged within channel 230 in the form of one or more rows (not shown in figure 3). The elements 30 preferably extend perpendicular to a longitudinal axis of the waste stream channel 230. In figure 3 the waste stream channel has in the centre thereof the same longitudinal axis as the longitudinal axis 201 in the centre of the burner module 200. The first disturbers 30 are preferably symmetrically arranged around or with respect to the longitudinal axis 201 of the waste stream channel. Likewise, the second disturbers 40 are preferably symmetrically arranged around or with respect to the longitudinal axis 201 of the second airstream channel 240. Such arrangement of second disturbers 40 is illustrated in figure 6A. Said figure 6A further shows (by way of example) that at least at least 3 disturbers are present per 45 “-segment around the longitudinal axis 201 of the burner module and/or waste stream channel.

Figure 3 further shows that the precombustion chamber 100 has side walls 101. The side walls are housing the burn zone BZ. The side walls have an angled part 70 adjacent the burner module. The angled part of the side walls extends under an angle a with respect to the longitudinal axis of the burner module which is preferably being between 10 - 75 ° to avoid dead zones. In figure 3, the angled part 70 of the side walls 101 of the combustion chamber 100 is directly adjacent the waste stream channel. In figure 4, the angled part 70 is directly adjacent the second air stream channel 240.

Figure 4 further shows an embodiment wherein the second airstream channel 240 is present in addition to the fuel stream channel 210, the first airstream channel 220 and the waste stream channel 230. The same or similar and corresponding features as shown in figure 3 are indicated with the same reference numerals. The waste stream channel 230 is provided with first disturbers 30. The first disturbers 30 may have one or more of the features as described above. The first disturbers 30 are arranged as having a first row 30a arranged upstream of a second row 320b, additional rows may be present. In figure 4, the burner module 200 has a second airstream channel 240 which can also be referred to a non-combustion stream channel since channel 240 is configured to deliver noncombustible stream AS2, such as a second airstream, into the precombustion chamber 100.

Figure 4 further shows that the airstream channel 240 is provided with second disturbers 40. The second disturbers are preferably configured for partially obstructing the stream AS2 to create a disturbed flow dAS2 downstream of the second disturbers 40. The disturbed flow downstream dAS2 is more turbulent than a flow of upstream of the second disturbers 40. The second airstream channel 240 is preferably configured such that the disturbed flow dAS2 is delivered between the burn zone BZ and the walls 101 of the precombustion chamber to create barrier zone AZ in between. By having flow dAS2 disturbed, thermal hotspots may be reduced.

Figure 4 illustrates that the first disturbers 30 are arranged in a first row 30a and a second row 30b. The rows 30a, 30b are preferably arranged in a staggered arrangement (see for example figure 6A). Notably, a third or further rows of first disturbers 30 may be present. Preferably, enough rows are present such that at least 1 row is present per meter of distance Lws of the waste stream channel 230, said distance Lws being measured between the inlet 231 of the waste stream channel 230 and the end of the waste stream channel from which the waste stream is injected into the burn zone BZ of the combustion chamber 100.

Figure 4 further shows that row 30b (closest to the combustion chamber) of the first disturbers is positioned at distance dm from the end of the waste stream channel 230, said distance is preferably at least at least of 150 mm, such as around 220 mm to ensure proper disturbance such that the burning behavior may be improved. The second disturbers 40 may be arranged within the second airstream channel 240 as shown. Figure 4 shows the second disturbers 40 arranged in a first row 40a and a second row 40 positioned upstream of the first row, the rows 40a, 40b are preferably arranged in a staggered arrangement. The first disturbers 30 and/or second disturbers 40 preferably extend substantially perpendicular to the longitudinal direction of the respective channel. It is preferred that the disturbers 30, 40 comprise at least 4, preferably at least 8 individual elements arranged substantially symmetrically around or with respect to the longitudinal axis 20 of respective channel and/or the burner module 200.

Figure 4 further shows that the second air stream channel 240 extends over a distance Las2 from inlet 241 to the end of channel 240 from which the second airstream AS2 is injected into the burn zone. It is preferred that at least one row of second disturbers 40 is present per meter of distance Las2.

Figure 4 (and figure 3) show that the burner module 200 may have a gas lance 5 to receive and to deliver a fuel stream to the burn zone BZ. The waste stream channel 230 is arranged around the gas lance in a mantle wise fashion meaning that the channel 230 surrounds the fuel channel 210 as seen from a cross section.

Figure 4 (and figure 3) further show that the burner module comprises an inner combustion air housing 2 and a waste gas housing 3. An optional outer combustion air housing 4 for receiving a noncombustible stream may further be present (as shown in figure 4).

The inner combustion air housing 2 is configured for receiving the first airstream AS1 via inlet 221. The waste gas housing 3 is configured for receiving the waste stream WS via inlet 231. Burner module 200 may further have the outer combustion air housing 4 for receiving the noncombustible stream AS2. The first disturbers 30, preferably positioned in rows within the waste stream channel 230, may be arranged such that they extend from the inner combustion air housing 2 to waste gas housing 3 (or the other way around). The first disturbers 30 preferably extend such that they form a connection between housings 2 and 3. The second disturbers 40 may be arranged such that they extend from housing 3 to housing 4 (or the other way around). The disturbers 40 preferably extend such that they form a connection between housings 3 and 4.

Figure 5 illustrates an exploded view of a burner module 200 showing the inner combustion air housing 2, the waste gas housing 3, the outer combustion air housing 4. The outer combustion air housing is not limited to the housing of air, any noncombustible stream may be used as explained earlier herein. Figure 5 shows that the housings are substantially cylindrical (as preferred). The housings form (at least a part of) the burner module when assembled. The outer sidewall 231 of the outer combustion air housing 4 is provided with the first disturbers 30. The outer sidewall 231 may form the first wall (inner wall) of the waste stream channel 230. The first disturbers 30 are arranged in rows, a first row 30a upstream of a second row 30b.

The outer sidewall 243 of the waste gas housing 3 is provided with the second disturbers 30.

The outer sidewall 243 may form the first wall (inner wall) of the second air channel 240. The second disturbers 40 are arranged in rows, a first row 40a upstream of a second row 40b.

Notably, reference numeral 30 may be used herein to refer to elements 30a and 30b. Likewise, reference numeral 40 may be used to refer to elements 40a and 40b.

Figure 5 shows that the first disturbers 30 and/or second disturbers 40 may be elongated elements. The first disturbers 30 and/or second disturbers 40 are shown to extend substantially perpendicular and away from the respective side wall. The first disturbers 30 and/or second disturbers 40 may have a length large enough such that, when the housings are assembled, the disturbers from a connection between adjacent housings.

Figure 5 further shows that individual disturbers within the same row are arranged symmetrically arranged around the longitudinal axis of the respective housing. The disturbers are preferably arranged such that in a same row, at least 3, preferably at least 4, more preferably at least 5 disturbers (or obstruction element) is present per 45 “-segment around the longitudinal axis the respective housing. This way, at least 12 disturbers are present around the longitudinal axis causing a desired disturbance which benefit the burning behavior.

Figure 6A shows the waste gas housing 3 (of figure 5) seen from a perspective view. The figure shows a first and second row of second disturbers 40a, 40b arranged on the outer side wall 243 of the housing 3. Figure 6A further shows the second disturbers as having a substantially cylindrical shape. It is understandable that the second disturbers 40 and first disturbers 30 may have any shape chosen from: a substantially cylindrical shape, a cone shape, a prism shape such as triangular prism shape, square prism shape, pentagonal prism shape, rectangular prism shape, hexagonal prism shape or trapezoidal prism shape, cuboid shape, rectangular shape, sphere shape, pyramid shape.

Figure 6B shows a schematic example of rows of the disturbers 30 and/or disturbers 40 are positioned in a staggered arrangement relative to each other (as explained earlier herein). Figure 7 illustrates in general a system for burning a waste stream WS. The burning can be useful to dispose waste material and/or to create heat or thermal energy. The thermal energy may be used to drive industrial processes. The system of figure 7 is an example of an industrial burner configured to receive and deliver a fuel stream FS, a first airstream AS1 and the waste stream into a burn zone within the combustion chamber 100. In addition thereto, a further noncombustible stream, such as a second airstream AS2 may be received and delivered into the burn zone.

The fuel stream FS can contain be any form of source to fuel or support the burning reaction, such as hydrogen (H2), natural gas, any hydrocarbon, any one of or a combination of methane, ethane and the like. The fuel stream can also be referred to as a “support gas”.

The waste stream WS can contain any matter to dispose and/or to burn, such stream can also be referred to as the “dirty air” or “sour gas” stream.

The first airstream AS1 typically contains oxygen for promoting oxidation within the burn reaction.

The noncombustible stream AS2 can contain air and/or any other gases such as nitrogen (N2) having a low heating value so that it does not burn upon the burn conditions within the combustion chamber. This stream can be used to create a cooling effect. By having such a stream, the walls may be protected via a barrier zone helping to protect them from the high temperatures produced within the burn zone.

Figure 8 shows examples of cross sections of embodiments of possible designs for the disturbers 30, 40. The disturbers may have a cross section shaped as a polygon, said shape preferably being chosen from a triangle (see 8.3), a square (see 8.4), a pentagon (see 8.5), a hexagon (see 8.6).

In particular embodiments, the first and/or second disturbers are oriented relative to the flow (being the flow of waste stream WS or second air stream AS2) of the respective stream (indicated with arrows in figure 8) such that an angle of the polygon is oriented towards and directly facing the upstream direction of the flow (see 8.3 C, 8.4C, 8.5C, 8.6C).

Figure 9 an embodiment wherein two fuel channels are used. The embodiment may have the same or similar features as explained earlier above. Figure 9 shows a system 1 for burning a waste stream, said system comprising a precombustion chamber 100 and a burner module 200, said precombustion chamber housing a burn zone BZ arranged downstream of the burner module, said burner module comprising a fuel stream channel 210, a first air channel 220 and a second fuel stream channel 210b and a waste stream channel 230 being configured to respectively deliver a first and second fuel stream FS1, FS2, a first air stream AS1 and the waste stream WS into the burn zone BZ of the precombustion chamber. The second fuel stream channel 210b is arranged for delivering the second fuel stream FS2 to the burn zone. This way a first fuel stream FS1 containing a first fuel and a second fuel stream FS2 containing a second fuel can be delivered to the burn zone BZ. In this manner, the burning behavior may be improved as the two channels allow for an improved regulation of the burning reaction. The improved burning behavior may as such be achieved via a process wherein the first fuel is delivered via the fuel stream FS1 to the burn zone, and wherein a second fuel, different from the first fuel, is delivered via a second fuel stream FS2, said second fuel being a H2 fuel, such as H2-gas. By having the combination of first and second fuels, emissions may be reduced. The first fuel can be a carbon containing fuel, preferably a hydrocarbon fuel and/or natural gas. In a preferred embodiment of such a process, the first and second fuel are delivered into the burn zone such that a 5 - 40 % fraction, preferably 5 - 20 %, more preferably 5 - 15 %, most preferably 5 - 10 % of total mass flow of both the first and second fuel delivered into the burn zone consists of the second fuel being the H2 fuel.

The channels may be arranged in any suitable manner as long as their respective streams are properly injected into the burn zone. It is preferred that fuel is injected into the center of the burn zone while being surrounded by oxygen from a direct adjacently arranged air stream channel. The air stream channel is preferably surrounded by a direct adjacently arranged waste stream channel.

Figure 10 shows the part of the fuel stream channel configured injecting fuel streams into the burn zone BZ. The fuel stream channels may be arranged in the same housing or may be arranged separately. Preferably, the first fuel stream channel FS1 and the second fuel stream channel FS2 are housed within the same housing, preferably a cylindrical housing. The fuel may be injected with a gas lance 5. Figure 10 further shows an example wherein blades 50 are arranged to modify the flow of the first airstream within combustion air housing 2. The blades are preferably present so as to have the first airstream delivered to the burn zone in a swirled fashion to improve the burning reaction. The air stream channel 220 as shown is delimited by the inner wall of the first combustion air housing 2 and the outer wall of the fuel stream housing which may be in the form of a gas lance 5. The housing of fuel stream channel and the air stream channel are preferably all cylindrical although other shapes may also work.

The fuel stream housing 5 a comprises a first fuel stream channel FS1 and a second fuel stream channel FS2. The two fuel stream channels are illustrated by figure 11 showing the fuel stream housing 5a as seen from inside the pre combustion chamber. The two fuel stream channels can be arranged in any suitable manner however, they are preferably surrounded by the first air stream channel 220 such that the two fuel stream channels extend in the center thereof. By having such channel arrangement, a good burning reaction can be ensured since the first airstream is injected into the burn zone in direct proximity of the fuel. The described embodiments and the figures are purely illustrative and serve only to increase understanding of the invention. The invention will not therefore be limited to the embodiments described herein, but is defined in the claims.

Claims

1. A system (1) for burning a waste stream, said system comprising a precombustion chamber (100) and a burner module (200), said precombustion chamber housing a burn zone (BZ) arranged downstream of the burner module, said burner module comprising a fuel stream channel (210), a first air channel (220) and a waste stream channel (230) being configured to respectively deliver a fuel stream, a first air stream and the waste stream into the burn zone of the precombustion chamber; wherein the waste stream channel is provided with obstruction elements (30) configured for partially obstructing the waste stream to create a disturbed flow of the waste stream downstream of the obstruction elements, wherein the disturbed flow downstream of the obstruction elements is more turbulent than a flow of the waste stream upstream of the obstruction elements; and wherein the waste stream channel is configured such that the disturbed flow of the waste stream is delivered into the burn zone of the precombustion chamber.

2. The system according to claim 1 , wherein the burner module extends along a longitudinal axis (201) and wherein the waste stream is fed to the waste stream channel of the burner module via a waste stream inlet (231) angularly positioned with respect to the longitudinal axis of the burner module, preferably such that the waste stream inlet has an inlet angle ( ) chosen from any angle between 30° to about 90°, such as 45° or 90°.

3. The system according to any one of the previous claims, wherein the waste stream channel (230) is delimited by a first and second wall, such as an inner wall (233) and an outer wall (232) respectively, extending in longitudinal direction of the burner module and wherein the obstruction elements extend between the first and second wall.

4. The system according to the previous claim, wherein the obstruction elements extend from the first wall (233) in the direction of the second wall (234).

5. The system according to claim 3 or 4, wherein the obstruction elements extend substantially perpendicularly between the first wall and the second wall.

6. The system according to any one of the previous claims 3-5, wherein the first and second wall of the waste stream channel are spaced apart by a spacing distance h, and wherein the obstruction elements extend over at least 30 % of the spacing distance h, preferably at least 50 % of the spacing distance h, more preferably at least 75 % of the spacing distance h.

7. The system according to any one of the previous claims 3-6, wherein one or more of the obstruction elements form a connection between the first wall (232) and the second wall (233) of the waste stream channel.

8. The system according to any one of the previous claims, wherein the waste stream channel extends from a waste stream inlet (231) to the precombustion chamber (100) over a distance Lws, and wherein obstruction elements (30, 30a) closest to the waste stream inlet are positioned at a distance di therefrom, said distance di being more than 50 % of distance L2 such that the obstruction elements closest to the waste stream inlet are closer to the precombustion chamber than to the inlet of the waste stream.

9. The system according to the previous claim, wherein distance di is less than 1 meter.

10. The system according to any one of the previous claims, wherein the obstruction elements (30) comprise one or more rows (30a, 30b) of obstruction elements arranged perpendicular to a longitudinal axis of the waste stream channel, and preferably arranged on a circumference of a circle having the longitudinal axis going through the centre thereof.

11. The system according to the previous claim, wherein obstruction elements within a same row of the one or more rows are symmetrically arranged around the longitudinal axis of the waste stream channel.

12. The system according to any one of the previous claims 10-11, wherein a plurality of the obstruction elements are arranged in a same row such that at least one, preferably at least two, more preferably at least three obstruction elements are present per 45 “-segment around the longitudinal axis of the waste stream channel.

13. The system according to any one of the previous claims 10-12, wherein the obstruction elements (30) comprise a first row of obstruction elements (30a) and a second row of obstruction elements (30b), wherein the first row (30a) is positioned upstream from the second row (30b) of obstruction elements.

14. The system according to the previous claim, wherein the obstruction elements in the first row of obstruction elements (30a) are positioned in a staggered arrangement relative to the obstruction elements in the second row of obstruction elements (30b).

15. The system according to any one of the previous claims, wherein the obstruction elements (30) are arranged in rows within the waste stream channel such that at least one row of obstruction elements is present per meter of waste stream channel.

16. The system according to any one of the previous claims, wherein the obstruction elements (30) are positioned at a distance dm of the precombustion chamber, wherein said distance dm is at least 150 mm, such as around 220 mm.

17. The system according to any one of the previous claims, wherein the obstruction elements (30) are elongated elements, preferably elongated elements extending substantially perpendicular to and away from the longitudinal axis of the burner module.

18. The system according to any one of the previous claims, wherein the obstruction elements (30) include at least 4, preferably at least 8 elements which are substantially symmetrically arranged around the longitudinal axis of the burner module.

19. The system according to any one of the previous claims, wherein one or more elements of the obstruction elements within the waste stream channel have a 3D shape chosen from: a substantially cylindrical shape, a cone shape, a prism shape, cuboid shape, rectangular prism shape, sphere shape, pyramid shape.

20. The system according to any one of the previous claims, wherein one or more elements of the obstruction elements within the waste stream channel have a cross section, when viewed in a direction perpendicular to the longitudinal axis of the burner module, shaped as a polygon, preferably a regular polygon, said shape preferably being chosen from a triangle, a square, a pentagon, a hexagon or shaped as a substantially circular shape.

21. The system according to the previous claim, wherein one or more of the obstruction elements is oriented within the waste stream channel such that an angle of the polygon is oriented towards an upstream direction of the waste stream.

22. The system according to any one of the previous claims, wherein the burner module further comprises a second airstream channel, said second airstream channel being configured to deliver a noncombustible stream (AS2) into the precombustion chamber.

23. The system according to the previous claim, wherein the precombustion chamber (100) comprises at least one side wall (101) housing the burn zone, and wherein the second airstream channel (240) is arranged to deliver the noncombustible stream between the burn zone and the side walls of the precombustion chamber to create a barrier zone for protecting the side walls from burn reactions within the burn zone.

24. The system according to any one of the previous claims 22-23, wherein the second airstream channel (240) of the burner module is provided with airstream obstruction elements (40) configured for partially obstructing the noncombustible stream such that a turbulent flow of noncombustible stream is delivered to the precombustion chamber.

25. The system according to any one of the previous claims 22-24, wherein the second airstream channel (240) is delimited by a first and a second airstream channel wall (242, 243), such as an inner airstream channel wall and an outer airstream channel wall respectively, extending in longitudinal direction of the burner module and wherein the airstream obstruction elements extend between the first and second wall.

26. The system according to the previous claim, wherein the first and second wall of the second airstream channel have a spacing distance h’ in between, and wherein the airstream obstruction elements extend over at least 30 % of the spacing distance h’, preferably at least 50 % of the spacing distance h’, more preferably at least 75 % of the spacing distance h’.

27. The system according to any one of the previous claims, wherein one or more of the airstream obstruction elements (40) form a connection between the first wall (242) and the second wall (243) of the airstream channel.

28. The system according to any of claims 22-27, wherein the airstream obstruction elements (40) within the second airstream channel (240) have one or more of the following features:

- comprise a first row of airstream obstruction elements (40a) and a second row of obstruction elements (40b), wherein the first row is positioned upstream from the second row in the second air stream channel and wherein said rows are preferably arranged in staggered arrangement relative to each other;

- have a 3D shape chosen from: a substantially cylindrical shape, a cone shape, a prism shape, cuboid shape, rectangular prism shape, sphere shape, pyramid shape;

29. The system according to any of the previous claims, wherein the burner module comprises a gas lance (5) to deliver a fuel stream to the burn zone of the precombustion chamber, wherein the waste stream channel is arranged at least partially around the gas lance, preferably substantially entirely around the gas lance in a mantle wise fashion.

30. The system according to any of the previous claims, wherein the burner module further comprises a second fuel stream channel (210b) arranged for delivering a second fuel stream (FS2) to the burn zone, the fuel stream containing a first fuel, the second fuel stream containing a second fuel.

31. The system according to any one of the previous claims, wherein the burner module comprises an inner combustion air housing (2) and a waste gas housing (3); wherein the inner combustion air housing is configured for receiving the first airstream (AS1) and the waste gas housing (3) for receiving the waste stream (WS); and wherein the burner module preferably further comprises an outer combustion air housing (4) for receiving a noncombustible stream, such as a second airstream (AS2).

32. The system according to the previous claim, wherein the obstruction elements (30) within the waste stream channel are arranged and extend between the inner combustion air housing (2) and the waste gas housing (3), preferably such that the obstruction elements (30) connect the inner combustion air housing (2) and the waste gas housing (3).

33. The system according to any one of the previous claims 30-31, wherein airstream obstruction elements (40) are arranged and extend between the waste gas housing (3) and the outer combustion air housing (4).

34. The system according to any one of the previous claims 31-33, wherein the housings (2, 3, 4) are substantially cylindrical.

35. The system according to any one of the previous claims, wherein the first airstream channel (220) of the burner module is provided with one or more blades (50) configured to modify the flow of the first airstream such that the first airstream is delivered to the burn zone in a swirled fashion.

36. The system according to any one of the previous claims, wherein the precombustion chamber has side walls with an angled part (70) adjacent the burner module, wherein said angled part of the side walls extends under an angle a with respect to the longitudinal axis of the burner module, said angle a being between 10 - 75 °.

37. The system according to any one of the previous claims, further comprising means (6) for controlling a flow ratio of first airstream (AS1) / noncombustible stream (AS2) into the precombustion chamber.

38. The system according to any one of the previous claims, wherein the first airstream (AS1) is fed to the first airstream channel of the burner module via a first airstream inlet (41) angularly positioned with respect to the longitudinal axis.

39. The system according to any one of the previous claims, wherein the fuel stream (F) is fed to the fuel stream channel of the burner module via a fuel stream inlet (211) angularly positioned with respect to the longitudinal axis.

40. The system according to any of the previous two claims, wherein one or more, preferably all, of the fuel stream (F), the first airstream (AS1) and the waste stream (W) is or are fed to a respective channel of the burner module via an inlet angle between 0° - 60°, preferably between 10° - 60°, more preferably between 25° - 50°, such as 30° or 45°.

41. Process of burning matter, said process comprising the steps of:

- delivering a fuel stream (F), a first airstream (AS1) and a waste stream (W) into a burn zone of a precombustion chamber such that the streams feed a burn reaction to burn matter;

- disturbing the waste stream before the waste stream is being entered into the precombustion chamber via obstruction elements such that a disturbed flow of waste stream is created downstream of the obstruction elements;

42. The process according to the previous process claim, wherein the process further comprises:

- delivering a noncombustible stream, such as second airstream (AS2), into the precombustion chamber;

- disturbing the noncombustible stream before the noncombustible stream is being entered into the precombustion chamber with airstream obstruction elements (30) such that a disturbed flow of noncombustible stream is created;

- delivering the disturbed flow of the second air stream into the burn zone of the precombustion chamber such that an barrier zone (AZ) for protecting the side walls from burn reactions within the burn zone is created.

43. The process according to any of the previous process claims, wherein a first fuel is delivered via the fuel stream (FS1) to the burn zone, and wherein a second fuel, different from the first fuel, is delivered via a second fuel stream (FS2), said second fuel being a H2 fuel, such as H2-gas.

44. The process according to the previous process claim, wherein the first fuel is a carbon containing fuel, preferably a hydrocarbon fuel and/or natural gas.

45. The process according to any of the previous two process claims, wherein the first and second fuel are delivered into the burn zone such that a 5 - 40 % fraction, preferably 5 - 20 %, more preferably 5 - 15 %, most preferably 5 - 10 % of total mass flow of both the first and second fuel delivered into the burn zone consists of the second fuel being the H2 fuel.

46. Use of the system and/or process according to any of the previous claims for the generation of heat.