WO2017007314A1

WO2017007314A1 - A burner nozzle configuration and its use

Info

Publication number: WO2017007314A1
Application number: PCT/NL2016/050485
Authority: WO
Inventors: Hermanus Johannus Theodorus Maria Taris
Original assignee: Hermanus Johannus Theodorus Maria Taris
Priority date: 2015-07-06
Filing date: 2016-07-06
Publication date: 2017-01-12
Also published as: MA42405A; EP3320262A1; US20180128482A1; NL2015096B1

Abstract

The invention relates to a device for cleaning a gas mixture comprising contaminants. The device comprises a cylinder and a burner nozzle for supplying a fuel to be burned, said burner nozzle being embodied for directing into the cylinder a flame, wherein the flame is directed in a flow direction of the gas mixture. The device is characterized in that the device comprises cone shaped gas conductor with a relatively wide entrance for the gas mixture to be cleaned and a relatively narrow exit, The tapered shape is positioned in the flow direction and the narrow part of which is positioned near or within the supply side of the cylinder, with the proviso that the device is embodied for supplying into the cylinder the gas mixture to be cleaned partly through the cone shaped gas conductor and partly around the cone shaped gas conductor. The burner nozzle is positioned at the narrow side of the cone.

Description

A BURNER NOZZLE CONFIGURATION AND ITS USE

The present invention relates to a burner configuration according to the preamble of claim 1.

Such burner configuration or device is known in the art. For example, in burners for hot air balloons cylinders are used so as to be able to direct the flame into the balloon. The cylinder used for this purpose is embodied to pre-heat the fuel, said fuel being supplied to the flame in a spirally wound pipe, so as to obtain a higher flame temperature.

Besides this purpose, such known burner configuration has no other advantages.

In addition to that, it is known to subject gasses to high temperatures for decomposing contaminants therein. Such decomposi^¬ tion may be obtained by oxidation or by decomposing the contaminants into degradation molecules, wherein said degradation may be performed without oxidation at high temperature. The burners used in such method may be open, wherein the flame usually is directed directly in the flow path of the gas mixture, hereinafter also identified as "the gas flow", and wherein the gas mixture can freely move around said flame.

The invention now aims at providing an improved burner configuration of the kind mentioned in the preamble.

The invention especially aims at providing a burner configuration of the kind mentioned in the preamble and that may provide an effective cleaning.

The invention also aims at providing an improved burner configuration that may yield a thorough mixing of the flame and the gas mixture to be cleaned.

So as to obtain at least one of the above mentioned goals the present invention provides a burner configuration or device comprising the features of claim 1. This burner configuration provides the advantage that a very thorough mixing of the flame and the gas mixture to be cleaned is obtained, such that contaminants are decomposed very efficiently. It has also shown that the present invention also yields a very reduced heating of the complete gas flow since the contact time is very short. Nevertheless, a very good and efficient decom^¬ position is obtained. Such synergetic result is completely unex- pected.

The device according to the present invention is embodied for guiding the gas mixture to be cleaned partly through the cone shaped gas conductor and partly around the cone shaped gas conductor and into the cylinder. To that end, in a supply path upstream from the device according to the invention a free space is provided around the cone, such that the gas to be treated that is supplied to the device is supplied partly through the cone and partly around the cone. Nevertheless, both parts will be supplied to the cylinder and as a consequence both parts are heated and where de- composition, disintegration of oxidation of the contaminants, will be obtained.

The ratio of the inner diameter of the cone to the inner di^¬ ameter of the cylinder may be in the range of at least 0.6 : 1, preferably at least 0.7 : 1, more preferably at least 0.8 : 1, and still more preferably between 0.7 : 1 and 0.9 : 1. A relatively larger amount of gas that is supplied through the cone and direct^¬ ly into the flame in combination with a smaller amount of gas that is supplied around the cone and mixed with co .bustion gases has shown to have an improved result. As a matter of fact, not 11 gas- es will have to be fed through the flame, requiring a larger amount of fuel, for example HHO gas, for providing a sufficient cleaning effect.

It is preferred that the exit of the cone is positioned in^¬ side the cylinder and the entrance to the cone is positioned out- side the cylinder. Such shows to have an improved mixing according to a first embodiment. It then is preferred that the outer diame^¬ ter of the cone is smaller than the inner diam.eter of the cylinder, as mentioned above for example in the range of at least 0.6 : 1, preferably at least 0.7 : 1, more preferably at least 0.8 : 1, and still more preferably between 0.7 : 1 and 0.9 : 1. Then, gas mixture that is supplied around the cone is still sucked into the cylinder due to the combustion of the fuel inside the cylinder. Such provides a suction effect of gas that flows outside the cone and even outside the outer diameter or circumference of the cylin^¬ der due to the high gas speed and thus the lower pressure inside the cylinder, obtained by the combustion inside the cylinder.

When a plurality of cylinders is positioned substantially ad jacently or with outer walls abutting each other in a flow path an space will remain between the cylinders through which a portion of the gas mixture can flow without coming into contact with the flames of the fuel from the burner nozzle. However, the combustion yields a so much higher gas speed and thus a lower pressure in the cylinder that gas that was supplied to the interstitial spaces is still sucked into the cylinder. Such effect seems to be greatest when the burner nozzle, or in any case the flame, is positioned at least partially inside the cylinder.

According to another aspect both the entrance and the exit of the cone are positioned inside the cylinder. As a consequence, a relatively large part of the gas mixture to be cleaned that is supplied into the cylinder, is fed through the cone. More in par^¬ ticular, the ratio of inner diameter of the cone to the inner di- ameter of the cylinder may be in the range of from at least 0.6 : 1, preferably at least 0.7 : 1, more preferably at least 0.8 : 1, and still more preferably between 0.7 : 1 and 0.9 : 1.

According to another aspect the invention provides for an embodiment wherein both the entrance to the cone and the exit are positioned outside the cylinder. Such yields a thorough mixing of gas mixture that is supplied to the cylinder though the cone and that is fed through the flame with gas that is sucked into the cylinder around the cone. With such embodiment a larger amount of gas mixture is fed to the cylinder around the cone. The shape of the cone provides a turbulence within the cylinder that ensures a god mixing of the second part of the gas mixture with the flame and wherein a good decomposition of contaminants is obtained. It is especially preferred that the ration of inner diameter of the cone to the inner diameter of the cylinder is in the range of 0.8 : 1 to 0.9 : 1.

An effective cleaning is especially obtained when the burner nozzle is provided at the exit of the cone, yielding an optimal mixing of the gas mixture to be cleaned but at the same time a short residence time of the gas mixture in the flame.

So as to obtain a good mixing, it is especially preferred that the flame covers a large surface area, which especially can be obtained when the burner nozzle is substantially distributed over the circurr.ference of the exit of the cone. It has thus shown that it is preferred that the device comprises at least two burner nozzles that are distributed over the circumference of the exit of the cone, more preferably three and still more preferably four, or even five or six, burner nozzles. A substantially continuous flame at the circumference is preferred mostly for obtaining an optimal distribution of gas mixture in the flame.

A suitable fuel for cleaning a gas mixture is a fuel that comprises H₂ and 0₂, preferably in a substantially stoichiometric ratio of 2 parts H₂ and 1 part 0₂. Such fuel only slightly increas^¬ es the temperature of the treated gas mixture because of the small heat content of the fuel whereas the high temperature of the flame provides a sufficient decomposition of the contaminants.

The invention allows to remove any kind of harmful substance from a gas, like organic substances and non-organic substances. For example, harmful organisms like bacteria and viruses are such "harmful substances". Examples of organic substances are dust and manure particles and hydrocarbons in substituted and unsubstituted form. An example of an inorganic substance is asbestos that can suitably be converted into in a harmless material by means of the present method and device. Due to the high flame temperature of a mixture of H₂ and 0₂, which rr.ay be more than 2000 °C, asbestos loses its rectangular shape so that it also loses its capacity to en^¬ ter human tissue, such as longue tissue. Confined environments that are contarr.inated with asbestos can be cleared from airborne asbestos particles in a short while by means of the method and de^¬ vice according to the present invention. By applying a fan, the particles that are settled onto the ground, and that cannot be re^¬ moved by any known method or device, will be returned to an air- borne situation such that they can be made harmless easily by means of the present method and device.

So as to make part of the oxygen in the fuel composition available for oxidative conversion of contaminants in the gas to be cleaned, it is preferred that the fuel comprises H₂ and 0₂ in a ratio of 2 parts H₂ and 1 to 1.2 part 0₂. Such embodiment is espe^¬ cially preferred when the gas to be cleaned comprises oxidizable contaminants. The part of 0₂ that is not used for oxidation of H₂ remains available for oxidation of non-burned oxidizable contami^¬ nants .

As mentioned above, it is preferred that the flames from the burner nozzles are substantially directed into a flow path of the gas to be cleaned, so as to obtain an intimate mixing of the flame with the gas mixture.

A balanced treatment of the gas mixture to be cleaned is finally obtained when the cone and the cylinder are positioned sub^¬ stantially coaxially.

According to another aspect, the present invention relates to a use of a burner configuration, or a burner device, according to the present invention for cleaning a gas that comprises contaminants, comprising the steps of supplying to the burner nozzle a fuel and igniting same for obtaining a flame, such that the flame is directed into the cylinder and the gas to be cleaned is sup^¬ plied via the entrance of the cone to the exit of the cone and is at least partially fed into the flame for heating and decomposing contaminants in said gas mixture. This use provides the advantages as mentioned above. The term "heating and decomposing" means that the contaminants are converted due to the high temperature or are oxidized by the oxygen present in the gas mixture. As a matter of fact, a slight excess of oxygen in the HHO mixture may be present for providing such oxidation. Therefore, a fuel comprising HHO, especially with slight excess oxygen, is preferred.

The device according to the present invention can suitably be used for cleaning gasses that contain large am.ounts of solid un- burned substances. Examples are exhaust gases from diesel engines, more in particular marine diesel engines. Also, cleaning of flue gases from power plants, such as coal fired power plants, and waste incinerators, can very suitably be carried out with the de^¬ vice according to the invention. As a result, the gases can be discharged directly into the environment without further treat merit .

It is especially preferred when the use comprises the step of supplying a fuel comprising H₂ and 0₂ to the burner nozzle. So as to obtain a suitable oxidation of oxidizable contaminants, it is preferred in the use according to the invention that the use com^¬ prises the step of supplying a stoichiometric excess of 0₂ in the fuel.

Hereafter, the invention will be described with reference to a drawing. The drawing shows in:

Fig. 1 a perspective view of a burner configuration according to the invention,

Fig. 2, 3 and 4 three alternative embodiments of the burner configuration according to the invention.

In the figures similar parts are referred to with the same reference numbers. However, for sake of ease of understanding, not all parts that are required for a practical em.bodiment are shown in the drawing.

Fig. 1 shows a perspective view of a burner configuration 1, hereinafter also called burner 1, according to the present inven- tion. The burner 1 comprises a (shown in dashed line) cylinder 2 and a cone 3, serving as a conductor for at least part of the gas mixture to be cleaned. The flow direction of the gas mixture to be cleaned is shown by means of arrows 4, 4'. Part of the gas mixture that is supplied through the cone is referred to by reference nu- meral 4, whereas part of the gas mixture that is supplied around the cone is referred to by reference number 4'. The cone 3 is positioned with its broad or wide side 5 relatively upstream and with the narrow side relatively downstream.

At the narrow side 6 a burner nozzle 7 is provided. At the burner nozzle a fuel is supplied for making flame 8. Said flame 8 is shown as two separate flames 8 but will preferably be provided at substantially the complete circumference of the narrow side 6 of burner nozzle 7. Gas mixture that is supplied via gas flow 4 through cone 3 and through flame 8, will for a short period be subjected to a high temperature of flame 8 such that contaminants in said gas mixture will be decomposed.

Fig. 2 provides a sectional view of the burner configuration 1. The cone 3 is positioned partly within and partly outside cyl^¬ inder 2. The gas flow 4, 4' that is supplied into the cone 3 and into the cylinder 2 has been shown in the drawing, as is the flow path of the gas mixture within the cylinder 2 after it has been guided through flame 8 and after it has been received in the cyl^¬ inder after it has been partially received within the interstitial space between the cone 3 and the wall of the cylinder 2. Mixing of both partial flows 4, 4' is clearly visible.

In Fig. 3 an alternative embodiment of the burner configura- tion 1 has been shown wherein the cone 3 is positioned fully within the cylinder 2. On the contrary, Fig. 4 shows an embodiment wherein the cone 3 is positioned fully outside the cylinder 2. In the embodiment according to Fig. 3 it is preferred that the cone 3 is smaller than in the embodiment according to Fig. 4. The ratio of the diameter of the widest part of the cone with respect to the inner diameter of the cylinder is, according to the embodiment of Fig. 3, clearly smaller than in the embodiment according to Fig. 4, so as to obtain a suitable flow of gas mixture 4, 4'.

The supply of fuel may be obtained through pipes that are po- sitioned at wide sides of the cones, said pipes comprising branch^¬ es to the burner nozzles, which are positioned near the narrow sides of the cone. If H₂ gas and O₂ gas are used as fuel, and also where other mixtures of any other fuel with oxygen are used, it is preferred that the fuel and the oxygen are supplied through sepa- rate pipes and are mixed only in or after the burner nozzle so as to yield a proper combustion.

The invention is not limited to the embodiments described herein and as shown in the drawing. The invention is limited only by the appended claims.

The invention also embodies all combinations of features that have been described herein before independently with respect to each other.

Claims

C L A I M S

1. A device for cleaning a gas mixture that comprises contami^¬ nants, comprising:

- a cylinder with a supply side for supplying to the cylinder the gas mixture and a discharge side for discharging from the cylinder the cleaned gas mixture and

- a burner nozzle for supplying a fuel to be burned, which burner nozzle is embodied for directing into the cylinder a flame, wherein the flam.e is directed substantially in a direction of flow of the gas mixture to be cleaned,

characterized in that the device comprises a cone shaped gas con^¬ ductor with a relatively wide entrance for the gas mixture to be cleaned and a relatively narrow exit, the tapered shape of which is situated in the direction of flow and the narrow portion of which is positioned near or within the supply side of the cylin- der, and wherein the burner nozzle is provided near the narrow portion of the cone, with the proviso that the device is embodied for guiding the gas mixture to be cleaned partly through the cone shaped gas conductor and partly around the cone shaped gas conduc^¬ tor and into the cylinder.

2. A device according to claim 1, wherein the exit of the cone is positioned inside the cylinder and the entrance to the cone is positioned outside the cylinder.

3. A device according to claim 1, wherein both the entrance and the exit of the cone are positioned inside the cylinder.

4. A device according to claim 1, wherein both the entrance to the cone and the exit are positioned outside the cylinder.

5. A device according to claim 1, wherein the burner nozzle is provided at the exit of the cone.

6. A device according to claim 1, wherein the burner nozzle is provided substantially distributed over the circumference of the exit of the cone.

7. A device according to claim 6, wherein the burner nozzle comprises at least two nozzles that are distributed over the circum-

5 ference of the exit of the cone.

8. A device according to any of the preceding claims, wherein the fuel comprises H₂ and 0₂, preferably in a substantially stoichiometric ratio of 2 parts H₂ and 1 part 0₂.

10

9. A device according to claim 8, wherein the fuel comprises H₂ and 0₂ in a ratio of 2 parts H₂ and 1 to 1.2 part 0₂.

10. A device according to claim 1 or 9, wherein the gas to be 15 cleaned comprises oxidizable contaminants.

11. A device according to any of claims 6 and 7, wherein the flames from, the burner nozzles are substantially directed into a flow path of the gas to be cleaned.

20

12. A device according to any of the preceding claims, wherein the cone and the cylinder are positioned substantially coaxially.

13. A device according to any of the preceding claims, wherein the 25 ratio of the diam.eter of the cone to the diameter of the cylinder is in a range of at least 0.6 : 1, preferably at least 0.7 : 1, more preferably at least 0.8 : 1, and still more preferably be^¬ tween 0.7 : 1 and 0.9 : 1.

30 14. Use of the burner configuration according to any of the preceding claims for cleaning a gas that comprises contaminants, com^¬ prising the steps of supplying to the burner nozzle a fuel and ig^¬ niting same for obtaining a flame, such that the flame is directed into the cylinder and a first part of said gas to be cleaned is

35 supplied via the entrance of the cone to the exit of the cone and is at least partially fed into the flame for heating and decompos^¬ ing contaminants in said gas mixture and a second part of said gas mixture is supplied into the cylinder around the cone for mixing said second part of the gas mixture to be cleaned with said heated first part.

15. A use according to claim 14, comprising the step of supplying a fuel comprising H₂ and O₂ to the burner nozzle.

16. A use according to claim 14 or 15, comprising the step of supplying a stoichiometric excess of 0₂ in the fuel.

17. A use according to claim 14, wherein the gas to be cleaned is air that is contaminated with asbestos.

18. A use according to claim 17, wherein the mixture of cleaned gas and corr.bustion products is returned to a confined environment.