WO2007141433A1

WO2007141433A1 - Burner and method for the regeneration of filtration cartridges and devices equipped with such burner

Info

Publication number: WO2007141433A1
Application number: PCT/FR2007/050982
Authority: WO
Inventors: Jean-Claude Fayard
Original assignee: Jean-Claude Fayard
Priority date: 2006-06-07
Filing date: 2007-03-22
Publication date: 2007-12-13
Also published as: EP2024614A1; FR2902137A1; FR2902137B1; US20090288399A1; CA2658216A1

Abstract

A burner designed to heat a filtration cartridge (5) for exhaust gases from an engine until oxidation and/or combustion of the solid particles trapped in the cartridge, including a burner body (2) presenting a closed extremity and, on the side opposite this closed extremity, an exhaust opening for said gases, characterised in that it includes: - at least an adduction pipe (7) of a mix of fuel and oxidiser opening into the burner body (2) tangentially to the burner body (2), in such a way as to cause the mixture to swirl around within the burner; - an electric means of igniting (8) said mixture positioned inside the burner body (2); - an obturator element (3, 18) blocking the burner body (2), to limit the turbulence of the exhaust gases in the volume of the burner body (2), restricted by said obturator element (3, 18).

Description

BURNER AND METHOD FOR REGENERATING FILTRATION CARTRIDGES AND DEVICES EQUIPPED WITH SUCH A BURNER

FIELD OF THE INVENTION

The present invention generally relates to the field of reduction, or even elimination, of solid particles such as soot contained in the exhaust gas from internal combustion engines, and in particular from diesel engines.

More particularly, the invention relates to a method for regenerating the filter cartridge (s) by burning soot trapped therein. Regeneration is the return of the filter cartridge to an operating state analogous to its initial state.

PRIOR STATE OF THE ART

The authorities have introduced increasingly stringent standards to force car manufacturers to develop engines that produce fewer and fewer emissions. Manufacturers are therefore striving to develop combustion engines, particularly diesel engines and lean-burn engines, which emit as little of the unburned particles as possible.

To this end, in addition to the development of new engines with ever lower fuel consumption, a special effort has been made on the development of new exhaust systems designed to reduce emissions of unburned pollutants and solid particles.

For example, automobile manufacturers have developed catalytic converters, usually consisting of a stainless steel casing, a thermal insulator and a honeycomb support impregnated with precious metals such as platinum (Pt) or aluminum. Rhodium (Rh). Such catalysts can reduce emissions of polycyclic hydrocarbons and carbon monoxide (CO), and this, in a proportion of the order of 90%.

However, they have no effect on solid particle emissions. Thus, such catalysts do not provide significant improvement in emissions of diesel engines producing many solid particles. However, the change in engine combustion is no longer sufficient to meet the discharge guidelines. This is why the implementation of exhaust gas filtration processes and devices with regeneration of combustion filters is now unavoidable. Such a filtration makes it possible to reduce by more than 90% the total mass of particles emitted by diesel engines.

In known manner, the solid particles are generally trapped by a filter cartridge forming the particulate filter. To work well, a particulate filter requires regeneration to burn the trapped particles in its filtering parts, mainly in the filter cartridge.

In order to withstand the high temperatures experienced especially during burning, a filter cartridge may be made of a porous body of cordierite, quartz or silicon carbide. In addition, it generally has a honeycomb structure to maximize its filtration area and to have a sufficient retention capacity to prevent clogging and, therefore, the reduction of engine performance.

In addition to the reduction in engine performance related to the pressure losses that entails the clogging of the particulate filter, the engines equipped with a particle filter of the prior art may suffer another harmful phenomenon.

Indeed, as clogging disturbs the engine, the exhaust temperature may increase, resulting in the sudden and untimely combustion of a large mass of solid particles, so that the temperature rises to values well above 1000 ⁰ C, may exceed the thermal resistance of the aforementioned materials constituting the filter cartridge. The thermal shock resulting from such combustion can thus have deleterious consequences on the structure of the particulate filter.

However, the major difficulty in ensuring the operation of such particulate filters lies in the possibility or not to achieve the oxidation and combustion phases of the solid particles retained by the filter cartridge. Indeed, on an urban route, the exhaust gas hardly reach a temperature sufficient to ensure the regular and / or complete combustion of the solid particles and thus regenerate the filter significantly limiting its clogging. However, in the absence of chemical additives, the carbonaceous particles resulting from the combustion of diesel in a diesel engine begin to oxidize only above a temperature of 45O ⁰ C and to burn from 55O ⁰ C. However, such temperatures are almost never reached in urban driving conditions. Therefore, it is necessary to implement a chemical process to facilitate the removal of these solid particles. Different techniques are thus used for the purpose of obtaining their combustion.

A first method of the prior art is to have, upstream of the filter cartridge, a catalyst for oxidation of nitrogen monoxide (NO) contained in the exhaust gas in nitrogen dioxide (NO ₂ ). Nitrogen dioxide (NO ₂ ) has the property of catalyzing the combustion of carbonaceous particles from a temperature of 25O ⁰ C. This technique, called "continuous regeneration trap" (English, "Continuons Regenerating Trap Or CRT), combines the effects of the particulate filter and the nitric oxide (NO) oxidation catalyst.

However, this process requires the use of a diesel fuel with a sulfur content of less than 50 ppm (parts per million), to maintain a conversion efficiency of nitrogen monoxide (NO) to nitrogen dioxide (NO ₂ ) sufficient . Such fuels are only available in the few countries that impose such a limit on their sulfur content, a limit that does not exist in many emerging countries.

In addition, to ensure proper operation of the filters, this technique requires regular regeneration to limit the filter pressure loss by eliminating the risk of uncontrolled regeneration, so too exothermic and destructive for the filter cartridge.

In the opposite case, given the excessive concentration of carbonaceous particles clogging the filter, the aforementioned violent reactions develop which consist of a too rapid combustion of a large mass of solid particles, which generally leads to destruction of the filter by thermal shock, the temperatures obtained may be locally too high.

Alternatively, a solution of the prior art proposes the use of organo-metallic additives added to gas oil such as cerium (Ce), iron (Fe), strontium (Sr), calcium (Ca) or others. This solution allows to obtain an effect similar to that obtained with nitrogen dioxide (NO ₂₎ by catalyzing the combustion of carbonaceous materials at temperatures of 37o ⁰ C. A first disadvantage of such a solution lies in the very high cost of the additives to be used. In addition, it is necessary to provide a device for introducing the additional additive, which further hinders the cost of such a solution.

Moreover, the additives present in the carbonaceous materials contribute to foul even more quickly the cartridge of filtration. Consequently, a solution of this type increases the risk of clogging of the particulate filter and therefore of uncontrolled reactions, when the temperatures reached during operation are not sufficiently high.

In addition, another combustion method has been implemented in recent direct injection diesel engines known as "common rail". It comprises a step of post-injection of diesel used to increase the temperature of the exhaust gas and thus be able to oxidize and burn the carbon particles retained on the particulate filter. The "common rail" direct injection method, which uses electromagnetic injectors, makes it possible to carry out a new injection of diesel fuel into the combustion chamber at the moment when the exhaust valve opens, realizing in this way a homogeneous mixture with the exhaust gases and thus triggering an oxidation reaction of the newly injected diesel. This oxidation reaction is completed quite completely on the oxidation catalyst located between the exhaust port of the engine and the particulate filter.

From the prior art, diesel fuel-type liquid post-injection processes are also known for the regeneration of filtration means arranged downstream of combustion catalysts in diesel engine exhaust systems. These processes are described in particular in the following documents: US-B-

5,207,990, EP-A-1,158,143, US-B-6,023,930, JP-A-07,119,444 and US-B-5,522,218.

However, such methods have the common drawbacks, on the one hand, of not allowing optimal, safe and economical regeneration of the filtration means and, on the other hand, of undergoing thermal degradation and coking of the regeneration liquid, in particular when it comes to diesel fuel, especially at the level of the nozzles of the injectors of post-injection. The post-injection means are thus quickly damaged by the heat generated by the exhaust manifold, which alters their reliability and efficiency. In addition, the known post-injection methods work satisfactorily only if a minimum exhaust gas temperature of about 300 ^° C. is reached for at least 5% of the operating time. Consequently, the devices and processes implementing the post-injection of diesel into the exhaust gas upstream of an oxidation catalyst become insufficient when the temperature is too low.

Another disadvantage of these systems lies in the parasitic and polluting emissions of hydrocarbons generated during the injection phase, when the temperatures are too low, for example around 300 ^° C.

Other techniques consist in employing devices comprising complementary heating means such as electric resistors or others. These additional heating means are implemented only when the cartridge has a start of clogging, that is to say during an increase in the pressure drop. Such a regeneration device operates when the engine is running, that is to say in the presence of a large flow of exhaust gas. Such a device therefore requires a significant heating power to bring the exhaust gas temperature and the mass of the filter cartridge to the correct temperature.

To achieve the combustion of solid particles retained on the filter, the prior art also proposes to have a burner at the filter inlet and turn it on when the engine of the vehicle is stopped. However, this involves many disadvantages, among which may be mentioned the difficulty of controlling, or even simply to initiate, the combustion in the burner, the difficulty of thermally insulating the filter, the significant rise in the temperature of the burner during the combustion phase (beyond 1400 ⁰ C) and the requirement to have a large filtration capacity to be able to provide a sufficiently long service, that is to say between two stops engine.

In most cases, the use of a burner to provide the calories necessary for the combustion of the solid particles has satisfactory operation only when the engine is stationary or idle, that is to say when the Regeneration conditions are the least favorable, because the temperature of the exhaust gas is then low. In addition, given the burning power to implement, the majority of devices has a footprint incompatible with the volume generally available in the particulate filter. In addition, such burners have real difficulties to operate satisfactorily during normal operation of the engine, because of the difficulty to ignite the burner due to severe turbulence in the exhaust line and therefore in the burner.

Such burners therefore require large and sophisticated systems, so expensive, to control these problems. The object of the present invention is to provide a method and a device for burning solid particles from the internal combustion of a heat engine solving the disadvantages of the processes of the prior art.

The object of the invention thus makes it possible to obtain the increase of the temperature necessary for the complete combustion of the solid particles, or soot, deposited on a filter cartridge, while being adaptable to numerous diesel engines and to very different engine operating conditions.

Another object of the invention is to provide a method and a device for burning solid particles, avoiding any risk of accumulation of particles in the filter cartridge and therefore any risk of inadvertent regeneration, whatever the operating conditions of the device. particularly for urban transport applications.

Furthermore, the invention also proposes a solution for quantitatively reducing, or even eliminating, solid particles, or soot, contained in the exhaust gases, by means of a regular, efficient and complete regeneration, that is, that is to say without interruption, by means of an oxidation reaction produced from 200 ⁰ C and a complete combustion below 400 ⁰ C, the use of an additive to avoid any risk of accumulation of particles in the filtration means despite a regeneration phase at low temperature.

Another object of the invention is to provide a burner for the quantitative reduction or elimination of soot contained in the exhaust gases of combustion engines, this burner opening at the inlet of the particulate filter and having dimensions reduced, which makes it compact and easily integrated on the exhaust system of a vehicle. Another object of the invention is to allow the regeneration of the filtering means implemented not entailing an excessive increase in the temperature of the gases at the outlet of the filtration device or significant overconsumption of fuel.

Furthermore, the invention aims to achieve a quantitative reduction, or even elimination, of the particles contained in the exhaust gas of an internal combustion engine, allowing the use of low concentration catalyst of precious metals.

Another object of the invention is to provide a solution for the quantitative reduction, or even elimination, of the soot contained in the exhaust gas of an internal combustion engine, which is relatively economical, reliable and flexible, and which delays clogging as much as possible. filter, or eliminating it, whatever the load of the engine, without being affected by the possible presence of sulfur compounds, such as sulfur dioxide in the exhaust gas. The object of the invention thus makes it possible to use gas oils with a high sulfur content.

A complementary object of the invention is to provide a method and a device for burning solid particles adaptable to the machines to regenerate the particulate filters to remove ashes deposited during their operation on a vehicle.

Furthermore, the invention provides a method and a device for burning solid particles adaptable to applications other than the combustion of soot in particulate filters. For example, given the small dimensions and the perfect control of a high energy combustion, it is possible to envisage the implementation of the object of the invention for drying foods, cereals and other sensitive products.

SUMMARY OF THE INVENTION

The object of the invention therefore relates to a burner for heating at least one filter cartridge for exhaust gas of an internal combustion engine at a temperature above the oxidation temperature and / or the combustion temperature solid particles trapped in the filter cartridge. This burner comprises a burner body, which has a closed end and, on the opposite side to this closed end, an exhaust opening capable of being connected to an exhaust gas discharge pipe.

According to the invention, the burner further comprises:

at least one adduct duct of a mixture of fuel and oxidant opening into the burner body in a direction substantially tangential to the burner body, so as to impart to the mixture a swirling motion within the burner body;

"an electric ignition means of the mixture positioned within the burner body;

¹ a shutter member obstructing a substantial part of the burner body, so as to limit the turbulence likely to be generated by the exhaust gas on the fluid flows within the volume of the burner body defined by the shutter member.

In other words, the burner - object of the invention comprises means limiting turbulence to a level compatible with the ignition of the mixture, whatever the engine speed, and therefore whatever the pressure variations likely to to intervene at the level of the exhaust, said mixture being injected in a manner conducive to ignition. This makes it possible to easily ignite the mixture in an area protected from turbulence, this ignition zone being delimited by the shutter element. Then, the combustion of the mixture can take place in the entire volume of the burner body thus producing high temperature gases capable of heating a filter cartridge to completely burn the solid particles.

In practice, the internal surface of the side walls of the burner body can be regular and generally has a symmetry of revolution.

By "regular" is meant a smooth surface (according to the common meaning of the term and not according to the mathematical definition), that is to say free of irregularities or, in the case of a symmetrical surface of revolution , a surface whose generator has a high radius curvature. It can for example be a straight cylinder, inexpensive form to obtain and easy to assemble on other elements. Such a feature can further limit turbulence within the burner body. According to a first embodiment of the invention, the shutter element may comprise a disc having a diameter slightly smaller than the internal diameter of the burner body, and positioned perpendicular to the axis of revolution, on the closed end of the burner body.

A disc thus dimensioned and positioned makes it possible to "break" the turbulence of the exhaust gas flows circulating in the burner body.

According to a practical embodiment of this first embodiment of the invention, the disk can be pierced with a plurality of holes whose number and / or diameters are proportional to the diameter of the disk. These holes are intended to allow the propagation of the combustion flame of the mixture throughout the volume of the burner body.

After ignition of the mixture, it allows to "develop" the combustion flame of the mixture throughout the volume of the burner body.

According to another embodiment of this first embodiment of the invention, the shutter member may further comprise a right cylinder whose one end is covered by the disk in question, and the other end is covered by the closed end of the burner body, the right cylinder being pierced with a plurality of through holes, whose number and / or diameters are proportional to the diameter of the disc, said orifices being intended to allow the propagation of the combustion flame of the mixing in the entire volume of the burner body.

Such a structure of the shutter member can greatly reduce turbulence in the ignition zone of the mixture; the combustion flame of the mixture can then propagate through the orifices throughout the volume of the burner body.

According to a second embodiment of the invention, the shutter member may consist of a valve disposed outside the volume of the burner body near the discharge opening, the valve surface corresponding substantially to the internal surface of the burner body, the valve being movably mounted under the action of a member such as a cylinder. A valve thus positioned and dimensioned also limits the turbulence of the exhaust gas in the burner body.

In practice, the burner may further comprise two concentric pipes, one for the supply of fuel and the other for the adduction of oxidant, the pipes being disposed upstream of the conduit.

This relative provision of these two pipes is likely to promote the mixing of the fuel with the oxidizer.

According to a particular embodiment of the invention, the adduction duct of the mixture may consist of a pipe extending along the side walls inside the body of the burner and parallel to the axis of revolution, the pipe having an angled end at right angles.

In practice, the burner may further comprise a second electric ignition means also positioned within the burner body, these electric ignition means being respectively constituted by a conventional heating candle and a conventional electric arc candle or by minus two heating candles.

These candles represent an inexpensive and simple mounting means for lighting the mixture.

According to a particular embodiment of the invention, the burner may comprise a second conduit for supplying a mixture of fuel and oxidant opening into the burner body in a direction substantially tangential to the burner body, so as to be able to print a symmetrical swirling motion within the burner body.

This makes it possible to evenly distribute the mixture in the ignition zone.

According to a practical embodiment of the invention, the burner may further comprise a control device for controlling the fuel and oxidant injection flow rates as a function of the signals delivered by a temperature sensor located in the burner body. and by a pressure sensor indicating the pressure drop due to clogging by said solid particles of said filter cartridge. When the burner is for example installed on a vehicle exhaust line, it can control its ignition and shutdown via the on-board computer.

In practice, the oxidant may be air from a turbocharger unit equipping the engine.

This provides a proper air flow and a homogeneous mixture with a high air speed for mixing.

According to an advantageous embodiment of the invention, a ceramic textile, in the form of a mat, fabric or felt, can be arranged on the closed end side of the burner body and in contact with at least one means. electrical ignition, said ceramic textile being able to capture and concentrate said mixture so as to promote its ignition.

According to another particular embodiment of the invention, the side wall defining in part the body of the burner may have one or more through holes, opening into said body above the shutter member. These through orifices are intended to allow the introduction into the body of the burner of a portion of the exhaust gas, when they still include a significant proportion of unburned oxygen in the engine itself.

This situation is generally encountered with supercharged diesel engines, for which it is not uncommon to observe a proportion of oxygen in the exhaust gas of greater than 10%.

In such a case, the energy released by the combustion of this residual oxygen is used, thereby making it possible to limit the quantity of fuel required for the operation of the burner.

In a variant of this embodiment, at least one of the orifices in question is likely to extend within the burner itself by a pipe, the end of which is oriented in the direction of the shutter element, in order to induce the concentration of the combustion in the lower zone of the burner, thus favoring the flame, and also making it possible to reduce the flame tube, and therefore the dimensions of said burner. The invention relates to an exhaust line of an internal combustion engine, comprising at least one inlet for gases from internal combustion, at least one filter cartridge for trapping the solid particles contained in these gases. exhaust and at least one exhaust port to the atmosphere of the gases located downstream of this filter cartridge. According to the invention, this line comprises at least one burner as explained above.

An exhaust line thus equipped makes it possible to regenerate its filter cartridge by oxidizing and / or by burning the solid particles that are retained therein, whatever the engine load.

In practice, the burner may be arranged upstream of the filter cartridge, inside or outside the exhaust line or near the filter cartridge.

This implantation in the vicinity of the filter cartridge limits heat losses between the burner and said cartridge. This allows to completely burn the solid particles with a minimum consumption of diesel.

According to a particular embodiment of the invention, the exhaust line may comprise:

at least two filter cartridges, said burner being housed between the two filter cartridges;

"Two valves for stopping the flow of exhaust gas reaching respectively each filter cartridge, so as to burn and / or oxidize said particles alternately in each filter cartridge.

Such a structure makes it possible on the one hand to minimize the distance, therefore the heat losses and the consumption of diesel fuel, between the burner and the filter cartridges and, on the other hand, to regenerate the particulate filter in turn, half by half.

According to another embodiment of the invention, the exhaust line comprises a folding flap, adapted to induce the introduction of a portion of the exhaust gas into the burner through through orifices which the latter can be provided, and thus allow the combustion of residual oxygen within said burner, may still be present within said exhaust gas. Furthermore, the invention also relates to a method for heating at least one exhaust gas filtration cartridge of an internal combustion engine at a temperature greater than the oxidation temperature and / or the combustion temperature. solid particles trapped in this filter cartridge, by means of a burner comprising a burner body having a symmetry of revolution, this burner body having a closed end and having on the opposite side to this closed end a discharge opening susceptible to be connected to an exhaust pipe.

According to the invention, this method comprises the steps of:

¹ to inject in a direction substantially tangential to the burner body, a mixture of fuel and oxidant, so as to print the mixture a swirling motion within the burner body; "supplying current to an electric ignition means positioned within the burner body, so as to ignite the mixture, the burner body comprising a shutter member obstructing a substantial portion of the burner body so as to limit the turbulence likely to be generated by the exhaust gases on the flows of fluids within the volume of the burner body defined by the shutter member;

¹ to interrupt the injection of mixture after the temperature within the burner body has exceeded a determined threshold so as to exceed this oxidation temperature and / or this combustion temperature at the level of the filtration medium for a period of time. parameters such as the load supported by the engine and the pressure drop due to clogging of the filter medium by these solid particles.

In other words, the method that is the subject of the present invention makes it possible to ignite the mixture in the burner, whatever the exhaust gas flows, because means therein limit their turbulence to a level compatible with the ignition of the mixture. , injected in a manner conducive to ignition. This makes it possible to easily ignite the mixture in an area protected from turbulence, delimited by the shutter element.

Then, the combustion of the mixture can take place in the entire volume of the burner body thus producing high temperature gases capable of heating a filter cartridge to completely burn the solid particles. In practice, the fuel and the oxidant can be mixed in stoichiometric proportions.

Furthermore, the invention also relates to a machine for regenerating the particle filter filtration cartridges comprising a burner as described above and a location for receiving at least one filter cartridge to be regenerated.

BRIEF DESCRIPTION OF THE FIGURES

The present invention and its advantages as will become apparent from reading the following description, made with reference to drawings which illustrate, without implying any limitation, embodiments of the invention and wherein: FIG ¹ IA is a schematic representation in section of an exhaust line equipped with a burner according to the invention; FIG IB is a schematic sectional representation of an exhaust line equipped with a burner according to the invention, according to an alternative to Figure IA as to the implantation of the burner; FIG 2A is a representation schematic in two sections of a burner according to a first embodiment of the invention; 2B is a diagrammatic representation in two sections of a burner illustrating a variant of the first embodiment of the invention; FIG. 3 is a diagrammatic representation in two sections of a burner according to another embodiment; of the first embodiment of the invention; "Figure 4 is a schematic representation in two sections showing another alternative to the embodiment illustrated by Figure 3; ¹ 5A is a schematic representation in two sections showing another alternative to the embodiment illustrated in Figure 3, in which the burner comprises two heating plugs and a ceramic fabric; FIG. 5B is a schematic two-section representation illustrating another variant of the embodiment of the invention illustrated in FIG. 3, in which the burner is equipped with an electric arc spark plug of the same type as that used on spark ignition engines;

FIG 6 is a diagrammatic representation in two sections illustrating another variant of the first embodiment of the invention illustrated by FIGS 2A and 2B.In this variant, the burner body is covered, at least partially, with a thermally insulating material; ¹ Figure 7 is a sectional schematic representation of a burner according to a second embodiment of the invention;

¹ 8 is a schematic representation in section of a burner according to the invention mounted on an exhaust line of an engine, the burner being supercharged by the turbocharger;

FIG. 9 is a diagrammatic representation in section of an alternative to FIG. 8 for supplying compressed air to a burner according to the invention;

¹ Figure 10 is a schematic representation in section of a burner according to the invention fitted to a filter device;

¹ Figure 11 is a diagrammatic section of a machine to regenerate the particulate filter independently of an engine exhaust line;

FIG. 12 is a diagrammatic representation in section of another embodiment of an exhaust line according to the invention.

13A is a diagrammatic representation in longitudinal section of the burner implemented within the line of FIG. 12; FIG. 13B is a diagrammatic cross-sectional representation of the burner used in the line of FIG. Figure 12.

MODES FOR CARRYING OUT THE INVENTION

In the exhaust lines illustrated in FIGS. 1A and 1B, the exhaust gases from the diesel engine arrive in the filtration device via an inlet 1, at a temperature which can be between 80 ^° C. at idle and 400 ^° C. C in charge. Such exhaust lines are each equipped with a catalyst 4, followed by a filter cartridge 5, upstream of which is mounted a burner according to the invention.

In this case, the burner has a symmetrical body of burner 2 having, according to a feature of the invention, a shutter member 3 positioned within the burner body 2.

A pipe 7 for supplying fuel and oxidant mixture opens tangentially into the burner body 2, so as to bring there gas oil or other fuel, conducted in the conduit 7 by a capillary 6, itself fed by an injector 61. Means (not shown) are provided for communicating to the oxidizer and fuel an appropriate amount of movement. to impress the mixture with a swirling motion in the burner body 2. Typically, the injection speed of the mixture in the burner body 2 can reach 300 m / s. By "tangentially" is meant tangentially to a circular section of the burner body 2 transversely to the axis of revolution of the burner.

The burner body 2 also has an end closed by a base and, on the opposite side to this closed end, an exhaust opening connected to the exhaust line.

Generally, the fuel injected into the pipe 7 is diesel fuel from the same tank as that of the internal combustion engine of the vehicle equipped with the exhaust line. Similarly, the oxidant is usually oxygen contained in the air injected into the conduit 7, for example from a source of air from the engine. According to a characteristic of the invention, the fuel and the oxidant are mixed in stoichiometric proportions.

Nevertheless, other fuels and / or oxidizers could be implemented without departing from the scope of this invention. In the example of Figure 2, the pipes 6, 7 bringing the diesel and the air are mounted concentrically. In addition, the duct 7 has a length determined so as to homogenize said mixture of air and diesel upstream of its connection to the burner body 2. Thus, a more homogeneous mixture is easier to ignite.

The duct 7 is thus supplied with air to form a combustible mixture of air and diesel fuel, which then opens out tangentially into the burner via a connection orifice 14. The burner body 2 also houses an electric ignition means in the form of a a hot candle 8 to cause ignition and combustion of this mixture of air and diesel, and a temperature sensor 9, the measurement of which controls the combustion process. The glow plug 8 is here of the incandescent type, that is to say of the type used on the chambers of the internal combustion diesel engine. The spark plug could also be of the apparent resistance type, which allows a direct contact of the fuel mixture with the incandescent filament.

In practice, to save the battery of the vehicle, it is possible to interrupt the power supply of the candle when the flame is sufficiently hot and "valiant" to burn the injected mixture thereafter. In practice, the interruption time is defined by a temperature threshold within the burner body. Then, the injection of mixture, and thus the combustion, is maintained for a predetermined period of time so that the filtration cartridge 5 exceeds the oxidation and / or combustion temperature of the solid particles.

On the other hand, it is possible to slightly incline the duct 7 towards the closed end of the burner body 2 (downwards in FIGS. 2 to 6), so as to further guide the mixture towards the spark plug 8.

The entire device is controlled by a control device or computer 10 which, from measurements made by a pressure sensor 11 and by the temperature sensors 9 and 12, controls the start of the burner to perform the regeneration phase, then adjusts the burner output to complete the regeneration operation. The exhaust gases are discharged through a pipe 13.

In this case, the ignition of the burner by the computer 10 comprises the phases consisting of:

"to electrically power the hot candle 8;

¹ to inject into the burner body 2 a controlled air flow via the tubular duct 7;

¹ after a predetermined time, corresponding substantially to the time required for the heating candle 8 to reach a temperature of between 600 ^° C. and 800 ^° C., to carry out, under the control of the computer 10, microinjections of diesel fuel by means of the injector 61 through a capillary 6 opening into the mixing pipe 7, and until ignition of a flame in the burner body 2, that is to say until the sensor of temperature 9 detects a significant heating in the burner enclosure;

to then simultaneously increase the diesel flow rate and the air flow rate controlled by the computer 10, in quantities and in such proportions as the temperature of the exhaust gas, measured by the temperature sensor 12 at the level of the inlet the filter cartridge, remains below 600 ⁰ C, temperature supportable by the catalyst 4 and the filter cartridge 5, this temperature being controlled by the computer 10, which also has information on the operating conditions of the engine to stop the combustion in the burner by a control of the computer 10, as a function of the operating time, of the measurement of the clogging of the filtration cartridge 5 by the pressure sensor 11 and / or the temperature measured downstream from the filtration device 4,5 to the exhaust pipe 13. According to one of its objectives, the invention aims to ensure proper operation and above all a correct start of the burner, whatever the operating conditions of the engine. In particular, the burner which is the subject of the invention makes it possible to ignite the mixture despite a motor at full power, ie when the conditions of extreme fluidic turbulence prevail in the burner, since the exhaust gases then circulate in the exhaust line at high speed and high speed.

For this, the inside of the body of the burner 2 has a shutter member 3 arranged substantially horizontally in Figures IA and IB. The shutter element 3 is located in a plane situated at a level below the orifice 14 for connecting the duct 7 to the burner 2. According to one embodiment of the invention, the shutter element 3 comprises a disc presenting a diameter slightly smaller than the internal diameter of the burner body 2, and positioned perpendicularly to the axis of revolution, on the closed end side of the burner body 2. In addition, this disc is pierced with several holes (here two, and about 1 to 10 depending on the diameter of the burner). In the example of the figures, the diameter of each of the holes is 7 mm. In general, it is possible to choose the number and the diameters of the holes in proportion to the dimensions of the burner body 2.

The shutter element 3 fulfills two functions contributing to the aforementioned objective. First, it obstructs a substantial portion of the burner body 2 so as to provide a cavity 15 under its surface in which a controlled turbulence reigns, by "breaking" the exhaust gas streams.

Second, it allows "to hang" and stabilize the flame during operation, that is to say, the combustion of the mixture of air and diesel. The verb "hang" reflects the phenomenon by which the flame is concentrated and stabilizes around this shutter member 3, before spreading to the rest of the burner body 2 through the holes of the disc. Once the flame is permanently established throughout the burner body 2, the temperature can exceed 1000 ^° C. to typically reach 1300 ⁰ C to 1400 ⁰ C.

In addition, the shutter element 3 defines a cavity 15 in which the ignition candle 8 for ignition can be housed, at least its active part, as shown in FIG. 1A, as well as the temperature sensor 9, as shown in FIGS. 2A, 2B, 6 or 7. The spark plug 8 is thus positioned on the end closed of the burner body 2, at a determined distance from the opening of the duct 7 so as to ignite the mixture.

In the example of the figures, the temperature sensor 9 is positioned in the body of the burner near the shutter member 3, so as to detect the ignition of the mixture and then adjust the richness thereof to optimize the temperature and burning time of the solid particles retained in the filter cartridge 5.

In the example described here, very satisfactory results have thus been obtained by placing the temperature sensor 9 protruding with respect to the outside of the shutter element 3 and away from the connection point of the duct 7 in the burner 2.

Such positioning makes it possible to obtain a flame temperature depending on the richness of the mixture when the burner is "in steady state".

By way of non-limiting example, a satisfactory operation of the burner with an efficient ignition has been obtained with a burner having the following dimensions: a cylindrical burner 2 of 60 mm internal diameter supplied with air by a rectilinear tangential tube 7 of 8 mm of internal diameter, receiving a capillary 6 with a 1 mm internal diameter allowing a maximum gas oil flow of 150 cm ³ / min, which represents a power of the order of 85 kW. The part of the burner 2 situated above the shutter element 3 has a length of 150 mm. The shutter element 3 is located 5 mm below the connection of the duct 7 in the burner 2; it has a diameter of 59 mm and is pierced with two holes 8 mm in diameter. The surface of the shutter element 3 delimits, with the bottom of the burner 2, a cavity 15 having a height of 25 mm. In this discussion, the term "cylinder" is used in its common sense, and so it refers to a straight cylinder with a circular base.

As soon as the burner reaches its steady state, the air flow is adjusted by the computer 10 so as to maintain the flame inside the cylinder defined by the burner body 2. The high turbulence and the high temperature level prevailing inside the burner promote rapid combustion occurring on about ten centimeters inside this cylinder.

In Figure IB is shown a variant where the burner is disposed directly inside the exhaust line. Such implantation of the burner makes it possible to fully recover all the heat released during the combustion of the mixture brought by the pipe 7. With a burner having the structure shown in Figures 2A and 2B, similar to that described in connection with Figures 1, the burner 2 can be arranged horizontally as illustrated. Nevertheless, it can also be arranged vertically, in which case it is essential to have the spark plug 8 on the bottom of the burner body 2 to obtain a good ignition. In FIGS. 2A and 2B, the orifice 14 represents the connection of the duct 7 in the burner 2, in this case an intersection between two cylinders of different diameters.

FIG. 2B shows a variant in which a part of the fuel is directly injected, during the ignition phase, through a heating candle opening into the cavity 15. This candle can be of the same type as that used in the additional burners of automobile heating circuit. Such an injection makes it possible to control the richness of the mixture and to distribute it within the cavity defined by the shutter element 3.

For a burner operating vertically, a structure such as that shown in FIGS. 3, 4 and 5 can be envisaged. This structure is similar to those illustrated in FIGS. 1, 2A and 2B. However, it has the particularity of having a shutter element "catchy" flame 3, consisting of a non-emerging cylindrical tube perforated laterally, whose upper end is actually covered by a solid disc. In addition, the enclosure defined by this tube houses at least one heating plug 8, centered or not on the base of the burner 2.

The shutter element 3 here consists of a stainless steel tube 1.5 mm thick and 35 mm internal diameter, covered with a solid disc. The tube can be plugged at its lower end by the base of the burner. The cylindrical surface, or side of the shutter member 3 is pierced with four holes 8 mm in diameter arranged in pairs opposite and at two different heights. These holes allow the flame to propagate throughout the burner body 2.

Other geometries are possible for the components of the burner, without departing from the scope of this invention. Thus, results similar to those previously indicated were obtained using a parallelepiped with a square section of 34 mm × 34 mm, centered on the axis of revolution of the burner body 2, also plugged at its ends and having only two holes of 8 mm diameter drilled mutually opposite. The use of these enclosures of circular and square section leads to similar results as to the quality of the ignition. Thus, with a burner 60 mm in internal diameter by 170 mm in height, arranged perpendicularly on the inlet section of a particulate filter of a "Renault Trucks Euro 2 MIDS 620 * 45" engine of 270 hp, the burner can be effectively ignited from the idle speed up to the maximum power, and this, for exhaust gas temperatures between 80 ^° C and 400 ^° C. The hot candle used is BERU ^® brand like those which equip the Renault 1.9 DCI 120 HP engines.

Furthermore, according to another embodiment of the invention, it is possible, to achieve the ignition phase, to mount several heating candles in the burner chamber, as shown in Figure 5A. The additional candles may be disposed inside or outside the cavity delimited by the shutter element 3.

In addition, the installation of a ceramic fabric 201, fabric, felt or mat near or in contact with the heating candle promotes the ignition phase of the mixture, because it is able to capture and concentrate the diesel mixture. It can be arranged as shown in FIG. 5A, ie housed between the wall of the burner body 2 and the heating plug 8 at least over part of the lateral circumference of the burner body 2. Likewise, 201 ceramic textile, could be incorporated on the burners described in connection with Figures 2A and 2B

It could be considered to use as a second spark plug a conventional spark or electric spark plug, of the type used in spark ignition engines, disposed substantially like the second spark plug 81 shown in Figure 5B.

For reasons of space, it is also possible to add fuel mixture inside the burner 2 by a tube 16 connected to the edge of the bottom of the burner 2, as shown in Figure 4. Such a duct adduction of the mixture consists of a pipe 16 extending along the side walls inside the body of the burner 2 and parallel to the axis of revolution, the pipe 16 having a bent end at right angles opening tangentially to the burner body 2. Such a pipe 16 has a lateral orifice 17, which opens tangentially to the burner body 2 and makes it possible to send the fuel mixture in the direction D. In the example of FIG. 4, the burner has the same dimensions than previously. Thus, the tube 16 made of stainless steel, has an internal diameter of 8 mm with a 4 mm diameter opening opening tangentially on the burner wall 2. Such a pipe 16 reduces the size of the burner, thus facilitating accessibility and manufacture of the burner.

FIG. 6 shows, in accordance with a characteristic of the invention, a variant in which a thermally insulating coating 180 covers the burner 2, so as to conserve the heat produced by the flame within the burner and to minimize the heat exchange. of the burner wall 2 with the outside. This coating may be a refractory metal of the inconel type or a ceramic such as cordierite, mullite, alumina etc. In addition, it is also possible to use a ceramic coating 180 associated with a sheath 181 made of refractory steel of small thickness, that is to say between 0.5 mm and 1.5 mm, so as to protect the ceramic thermal shocks. Such thermal insulation makes it possible to more quickly reach the oxidation and / or combustion temperature of the solid particles in the filtration cartridge 5, while saving the fuel injected into the burner.

Thus, given the rapidity of combustion and maintenance at a high temperature of the walls, it is possible to burn any kind of liquid or solid fuel, without necessarily bringing a large excess of air. The use of a longer burner 2 makes it possible to lengthen the combustion time of the mixture to complete the combustion.

To promote combustion and ignition, a burner object of the invention can advantageously find application for the drying of cereals or vegetables, where the air is generally heated by natural gas. In this case, to limit or cancel parasitic emissions, a catalytic coating may advantageously be deposited on the outer wall of the burner 2. Such a catalytic coating allows to oxidize the last traces of hydrocarbons and carbon monoxide (CO). In addition, it is possible to have a catalyst at the outlet of the burner, in the form of a honeycomb to increase the exchange surface.

For applications with very high turbulence, the burner object of the invention can be equipped with a shutter element in the form of a disc defining a valve 18, as shown in FIG. 7. In accordance with the invention, the valve 18 controlled by a jack 19 substantially obstructs the burner body 2, in this case the discharge orifice of the burner, so as to limit the turbulence of the gaseous flows in the burner. When starting, the cylinder 19 controlling the valve 18 can be simply controlled by a bypass of the air burner feed. Then, when the flame is detected by the thermal sensor 9, be placed in the free position, or "in neutral", that is to say without pressure difference between its chambers. Advantageously, this valve 18 may be associated with a shutter element 3, as described above in relation to FIGS. 1 to 6.

Furthermore, in the embodiment illustrated in Figure 7, the bottom of the burner 2 is in sphere portion. The temperature sensor 9 is arranged, like that shown in Figures 2, on the bottom of the burner 2. The spark plug 8 is arranged on the side or the center depending on whether the burner is intended to operate horizontally or vertically.

In addition, it is necessary to provide a source of compressed air to power the burners mounted on the exhaust lines of the bus engines, trucks and other high-power diesel engines. For this, in all operating conditions, air can be used stored at about 10 bar in the tank for supplying the vehicle accessories.

When such a source of compressed air is not available, it is possible to mount a booster or even to use the air of the booster circuit of the engine, as shown in Figures 8 and 9. Thus, compressed air is taken from a turbocharger 20 at the engine inlet by means of a bypass duct 21, able to derive the air flow necessary for the supply of the burner. A regulator 22 controls the air flow in this bypass duct 21 so as to regulate, under the control of the computer 10, the amount of air entering the filtration device.

Alternatively, as shown in FIG. 9, it is possible to have a compressed air reservoir 23 to supply, again via a bypass 21 coming from the turbocharger and a non-return valve 24. The flow rate The burner feed is also adjusted by the flow regulator 22, which may for example be constituted by a variable opening valve. To increase the air flow by using the charge air, it is also possible to use a small turbo blower machine arranged between the compressed air reservoir 23 and the flow regulator 22, to increase the flow rate and the pressure. Available pressure in the bypass duct 21. The turbo blower machine may for example consist of a vane pump, electrically powered and generating a pressure difference of 400 mbar. In addition, many diesel engines are equipped as standard with a catalyst to reduce hydrocarbon and carbon monoxide (CO) emissions to meet emission standards. Alternatively, diesel engines, such as those conforming to the so-called EURO 4 standard, may be equipped with a nitrogen oxide reduction system called "SCR" incorporating a denitrification catalyst called "DéNox", capable of reducing, on the one hand, nitrogen oxides (NOx) by means of urea injection, in addition to the use of an oxidation catalyst to reduce the possible excess of urea, and on the other hand, the emissions hydrocarbons and carbon monoxide (CO) remaining exhaust gases. A filtration device comprising only a burner according to the present invention therefore makes it possible, in such applications, to provide a set without oxidation catalyst, simple and economical.

Thus, the burner illustrated in FIG. 10 is disposed between two filter cartridges 5 each comprising a conventional filter cartridge, opening onto the inlet face of each of the cartridges, which are furthermore equipped with a controlled obstruction valve 25. by a jack 26 with pneumatic or electric motor. The obstruction valve 25 allows the regeneration of one cartridge after the other by combustion of the carbon particles retained on their filter cartridges, thus avoiding excessive outlet temperatures. Each of the filtration cartridges 5 is equipped with a temperature sensor 27, fulfilling a function similar to that of the temperature sensor 9 illustrated in FIG. 1. In addition, a temperature sensor 273 disposed on the burner outlet pipe, allows precise control of the exhaust gas outlet temperatures by controlling the clogging of the valve 25 of the filter cartridge 5 to be regenerated.

As before, a pressure sensor measures the back pressure due to pressure drops by clogging of the filter cartridges 5, so as to indicate the level of clogging of the filter cartridges. Beyond a determined sealing threshold, the computer controls the start of the burner so as to regenerate the filter. For this, the starting method comprises the steps of: "supplying the heating candle 8; ¹ to inject a flow of air by means of the conduit 7; • to close one of the two valves 25 controlled by a jack 26; ¹ after a predetermined time corresponding substantially to the time required for the heating candle 8 to reach a sufficient temperature of between 600 ^° C. and 800 ^° C., to carry out, under the control of the computer 10, micro-injections of diesel fuel through the capillary 6 and the tube 7 by means of the injector 14, until the temperature sensor 9 detects a significant increase in the temperature in the chamber 2 of the burner; to maintain combustion as long as the temperatures measured by the temperature sensors 27 at the outlet of the filter cartridge are less than 500 ^° C., the threshold beyond which combustion of the carbon takes place in the corresponding filter cartridge; exceeding this threshold, to control via the calculator simultaneously stopping the burner and opening the valve 25 of the filter cartridge 5 obstructed.

Subsequently, the combustion continues in the filter cartridge 5, but without nevertheless reaching an unacceptable gas temperature at the outlet of the filter cartridge, since the carbon combustion gases from a filtration cartridge 5 are mix with those from the adjacent filter cartridge 5 where no combustion reaction is started. Indeed, the regeneration of the other filter cartridge will be initiated only later and after a programmed time in the computer 10, long enough for the combustion on the filter cartridge 5 is complete or equal measured temperatures by the probes 27.

Thus, according to such a method, the power of the burner is used only to heat a single cartridge at a time, which significantly reduces its operating time and, therefore, the amount of fuel consumed for this operation.

For example, in the case of a 177 kW engine operating at half load, with inlet exhaust gas temperatures of 300 ⁰ C and meanwhile, at each combustion, that the temperature of the filter cartridge is between 295 ⁰ C and 300 ⁰ C, tests were conducted according to two different methods. First, the above-described method of regenerating the filter cartridges 5 in turn has been implemented. Was then simultaneously both regenerated filter cartridge 5. For each test, the burner is stopped when the temperature measured downstream of the cartridge filter 5 filtering reaches 500 ⁰ C. The filter cartridge 5 used in the context of these tests are silicon carbide and each cartridge has a diameter of 143.8 mm for a length of 254 mm.

Thus, for a burner power corresponding to a fuel consumption of 50 cm ³ / min, the following operating times are obtained:

¹ for one operation in turn, the duration has varied from 20 to 25 s, and the outlet temperature does not exceed 47O ⁰ C, temperature corresponding substantially to the case where the burner is stopped with simultaneous opening of the valve obstructing the other filter cartridge 5. Shortly after, this temperature is around 45O ⁰ C during the combustion of carbon and then, at the end of the combustion, drops back to the level of the exhaust gas inlet temperature, ie about 300 ⁰ C;

"When the two cartridges are in communication, the total burning times are between 85 and 100 s, and there have even been differences in reheating between the two filter cartridges 5. The differences thus observed over time are due to the fact that that the burner is stopped only when the outlet temperature is greater than 500 ⁰ C on the two filter cartridges 5. For the same level of clogging of the cartridges, that is to say 6 g / 1 it was measured temperature peaks exceeding 65O ⁰ C.

These tests therefore show that the regeneration of the filter "in turn" significantly reduces the overconsumption of diesel required for each combustion. Thus, in the example above, the overconsumption is divided by two.

In addition, in terms of safety, as has been seen previously, the valves 25 also make it possible on the safety level to reduce the exit temperatures significantly and, consequently, to overcome a significant thermal insulation of the exit line. This valve device can therefore advantageously be incorporated devices comprising a burner. According to a preferred characteristic of the device that is the subject of the invention, each of the filtration cartridges 5 has a means of obstruction of the flow rate, arranged upstream or downstream, and controlled by at least one calculator integrating the operating conditions of the engine. , so as to isolate at least one filter cartridge 5 whenever the accelerator position is at zero (not accelerated).

According to another embodiment of the invention, it is advantageous to use the burner which is the subject of the invention on a machine intended to regenerate the filter cartridges for particle filters in order to renovate them after the vehicle has traveled several tens thousands of kilometers. Indeed, even if the combustion of carbon is perfectly carried out at the level of the filtering device, after several thousand kilometers the ashes resulting from the combustion of the engine oil, or even the combustion additives used, tend to progressively seal up the porosities. filter cartridge. This is why regeneration carried out on a machine, with a device blowing hot air against the direction of operation, allows to properly regenerate the filter cartridge out of the vehicle.

Such a machine for regenerating the particulate filters is illustrated in FIG. 11, in which the burner 2 operates in a horizontal position within a chamber 32, itself fed by a turbo-blower machine 31. the turbo blower and the power of the burner 2 are controlled by a computer (not shown), so as to adjust the temperature at the outlet of the chamber 32 to a set temperature indicated by the temperature sensor 28. The principle is to increase gradually the temperature of the air within the burner to a temperature close to that where carbon combustion occurs, that is to say 500 ⁰ C without additive, or 350 to 400 ⁰ C with additive.

At the outlet of a filter cartridge to be regenerated 29, a second temperature sensor 30 is provided, so as to continuously compare the temperature at the outlet 13 with the inlet temperature measured by the sensor 28. In the case where the outlet temperature exceeds the inlet temperature, means are implemented to slow down the combustion in the filter, such as reducing the air flow, reducing the power of the burner. This method of slowing the combustion burns all the carbon and residues contained in the filter without reaching excessive temperatures that could jeopardize the integrity and longevity of the filter cartridge. Once the combustion phase is over, the temperature of the filter cartridge increases to a temperature of between 650 and 700 ^° C. so as to reduce all the residues to ashes. Then, a large flow rate is generated by the turbo blower machine so as to extract these ashes from the filter cartridge to be renovated. The hot gases are discharged through a pipe 34 thermally insulated, having a special filter 35 of large capacity, able to stop all ashes and residues. Downstream of this special filter is disposed an oxidation catalyst 36 for oxidizing the hydrocarbons and carbon monoxide (CO) possibly formed during the combustion phase. The gases are finally discharged via a conduit 37.

According to another variant of the invention, more particularly described in relation with FIGS. 12 and 13, it is desired to take advantage of the residual oxygen present in the exhaust gases, with a view to its combustion in the burner. This case is particularly encountered in supercharged diesel engines.

For this purpose, the body of the burner is provided with one or more through holes 38, opening on the side wall defining said body, at a higher level with respect to the shutter element 3. This or these orifices 38 are advantageously oriented substantially tangentially with respect to said side wall, still for the purpose of contributing to the swirling motion printed on the flows inside the burner.

In order to induce the introduction of part of the exhaust gases into the burner, the exhaust line is provided with a flap 39, articulated on the inner wall of said line, and may be more or less folded down on the outer wall of the burner, on behalf of the computer 10 according to the parameters already mentioned, and corollary causing the introduction of a greater or lesser amount of said exhaust gas into the burner.

In doing so, we take advantage of the energy released by the combustion of oxygen in the burner, and corollary, it reduces the amount of fuel required for the operation of the latter.

In addition, at least one of said orifices extends into the burner through a pipe 41 whose end 42 is bent and directed towards the shutter element 3. In doing so, it is concentrated at the latter combustion, promoting the flame, and corollary, to reduce the length of said burner.

The burner which is the subject of the present invention thus makes it possible to reduce or even eliminate solid particles contained in a filtration cartridge while using a catalyst with a low concentration of precious metals. Indeed, such a burner allows a complete combustion of diesel without parasitic emission of hydrocarbons or carbon monoxide, unlike devices where diesel fuel is injected directly onto the catalyst.

Other embodiments of the invention are possible without departing from the scope of this invention. Thus, as shown in FIG. 3, the burner may comprise a second conduit for supplying a mixture of fuel and oxidizer, opening into the burner body also in a direction substantially tangential to the burner body, so as to be able to print to the mixture a symmetrical swirling motion within the burner body.

Claims

Burner for heating at least one filter cartridge (5) of the exhaust gas of an internal combustion engine at a temperature above the oxidation temperature and / or the combustion temperature of the solid particles trapped in said filter cartridge (5), said burner comprising a burner body (2) having a closed end and having on the opposite side to said closed end an exhaust opening capable of being connected to a pipe for discharging said gas exhaust; characterized in that it further comprises:

at least one conduit (7) for supplying a mixture of fuel and oxidant opening into the burner body (2) in a direction substantially tangential to the burner body (2), so as to be able to print to said mixture a swirling motion within the burner body (2);

an electric ignition means (8) for said mixture positioned within the burner body (2);

a shutter member (3, 18) obstructing a substantial portion of the burner body (2), so as to limit the turbulence likely to be generated by said exhaust gases on the fluid flows within the body volume; burner (2) delimited by said shutter member (3, 18).

2. Burner according to claim 1, characterized in that the inner surface of the side walls of the burner body (2) is regular and generally has a symmetry of revolution.

3. Burner according to claim 2, characterized in that the shutter member comprises a disc (3) having a diameter slightly less than the internal diameter of said burner body (2), and positioned perpendicular to the axis of revolution, on the side the closed end of the burner body (2).

4. Burner according to claim 3, characterized in that the disk (3) is pierced with a plurality of holes, whose number and / or diameters are proportional to the diameter of the disc (3), said holes being intended to allow the propagation of the combustion flame of the mixture throughout the volume of the burner body (2).

5. Burner according to claim 3, characterized in that the shutter member further comprises a straight cylinder whose one end is covered by said disk and whose other end is covered by the closed end of the burner body (2). said right cylinder being pierced with a plurality of holes whose number and / or diameters are proportional to the diameter of the disc (3), said holes being intended to allow the spread of the combustion flame of the mixture throughout the burner body volume (2).

6. Burner according to claim 2, characterized in that the shutter member consists of a valve (18) disposed outside the volume of the burner body

(2) near said discharge opening, the area of said valve (18) corresponding substantially to the internal surface area of the burner body (2), said valve (18) being movably mounted under the action of a member such as a cylinder (19).

7. Burner according to one of the preceding claims, characterized in that it further comprises two concentric pipes (6, 7), one for the adduction (6) of fuel and the other for the adduction of oxidant, said ducts (6, 7) being arranged upstream of said duct (7).

8. Burner according to one of claims 2 to 7, characterized in that the adduction pipe of the mixture consists of a pipe extending along said side walls inside the body of the burner (2) and parallel to the axis of revolution, said pipe having an angled end at right angles.

9. Burner according to one of the preceding claims, characterized in that it further comprises a second electric ignition means (80) also positioned within the burner body (2), said first and said second electric means ignition (80) being respectively constituted by a conventional heating candle and a conventional electric arc candle or by at least two heating candles.

10. Burner according to one of the preceding claims, characterized in that it comprises a second conduit (7) for supplying a mixture of fuel and oxidant opening into the burner body (2) in a substantially tangential direction. to the burner body (2) so that a symmetrical swirling movement within the burner body (2) can be imparted to said mixture.

11. Burner according to one of the preceding claims, characterized in that it further comprises a control device (10) for controlling the injection rates of fuel and oxidant according to the signals delivered by a temperature sensor. (9) located in the burner body (2) and by a pressure sensor indicating the pressure drop due to clogging by said solid particles of said filter cartridge (5).

12. Burner according to one of the preceding claims, characterized in that the oxidant is air from a turbocharger fitted to said engine.

13. Burner according to one of the preceding claims, characterized in that a ceramic textile (201), in the form of mat, fabric or felt, is disposed on the side of the closed end of the burner body (2). ) and in contact with at least one electric ignition means (8, 80), said ceramic fabric (201) being able to capture and concentrate said mixture so as to promote its ignition.

14. Burner according to one of the preceding claims, characterized in that it comprises at the side wall defining in part, one or more through holes (38, 40), opening into the body of the burner above the shutter member (3), intended to allow the introduction into said body of a portion of the exhaust gas.

15. Burner according to claim 14, characterized in that at least one (40) of the through holes, extends within the burner by a pipe (41), the end (42) is bent and directed in the direction shutter member (3).

16. Exhaust line of an internal combustion engine, comprising at least one inlet for the gases resulting from said internal combustion, at least one filtration cartridge (5) intended to trap the solid particles contained in said exhaust gases. said engine and at least one exhaust port to the atmosphere of said gas located downstream of said filter cartridge (5), characterized in that it comprises at least one burner according to one of the preceding claims.

17. Exhaust line according to claim 16, characterized in that the burner is disposed upstream of the filter cartridge (5), inside or outside said exhaust line or in the vicinity of said filter cartridge (5).

18. Exhaust line according to one of claims 16 and 17, characterized in that it comprises:

"at least two filter cartridges, said burner being housed between the two filter cartridges;" two valves (26) for stopping the flow of exhaust gas reaching respectively each filter cartridge, so as to burn and / or oxidizing said particles alternately in each filter cartridge.

19. Exhaust line according to one of claims 16 and 17, characterized in that it comprises a flap (39) folding on the outer wall of the burner, to induce the introduction within the latter part exhaust gas.

20. A method of heating at least one filter cartridge (5) of the exhaust gas of an internal combustion engine at a temperature above the oxidation temperature and / or the combustion temperature of the trapped solid particles. in said filter cartridge (5), by means of a burner comprising a burner body (2) having a symmetry of revolution, said burner body (2) having a closed end and having on the opposite side to said closed end a exhaust opening capable of being connected to a pipe for exhausting said exhaust gas; characterized in that it consists of:

injecting, in a direction substantially tangential to the burner body (2), a mixture of fuel and oxidant, so as to impart to said mixture a swirling movement within the burner body (2);

"supplying current to an electric ignition means (8) positioned within the burner body (2), so as to ignite said mixture, said burner body (2) comprising a shutter member (3, 18) obstructing a substantial portion of the burner body (2) so as to limit the turbulence likely to be generated by said exhaust gas on the flows of fluids within the volume of the burner body (2) delimited by said shutter member (3, 18);

to interrupt the injection of mixture after said oxidation temperature and / or said combustion temperature has been reached for a duration depending on parameters such as the load borne by the motor and the pressure drop; due to clogging of the filtering medium by these solid particles.

21. Heating method according to claim 17, characterized in that the fuel and the oxidant are mixed in stoichiometric proportions.

22. Machine for regenerating the particle filter filtration cartridges, characterized in that it comprises a burner according to one of claims 1 to 13 and a location for receiving at least one filter cartridge.

(29) to regenerate.