DE102014015786A1 - Device for removing solid fractions from the flue gas of internal combustion engines or industrial gas turbines - Google Patents

Abstract

The invention relates to a device for removing solid fractions from the flue gas of internal combustion engines (7) or industrial gas turbines, the device having a structure with metallic particles and the metallic particles being connected to a felted or felt-like metal structure (1) and attached to a flat support structure (FIG. 2) are arranged.

Description

The present invention relates to a device for removing solid fractions from the flue gas of internal combustion engines or industrial gas turbines, the device having a structure with metallic particles, according to the preamble of claim 1.

The removal of solids from the flue gas of internal combustion engines by means of particle filters is known for example from the motor vehicle field. It has also become known to use felted filter structures for flue gas cleaning in power plants, which are periodically cleaned by means of compressed air in order to avoid increased pressure losses due to the excessive buildup of a filter cake on the filter structure. The filter materials used for this purpose usually have a temperature resistance in the range of 220 to 250 ° C, while the exhaust gas temperature of increasingly used in power plant technology internal combustion engines in the range of 380 to 400 ° C and the exhaust gas temperature of used in power plant technology also industrial gas turbines in the range of 500 to 600 ° C is located.

The filter structures used hitherto are unsuitable for use in the abovementioned temperature range of internal combustion engines and industrial gas turbines. Filter structures for hot gas filtration in the form of sintered filters or metal foam filters have therefore already become known, but their degree of separation in relation to the pressure losses generated by the filters is unfavorable and their production is cost-intensive.

Based on DE 11 2008 003 152 T5 For example, a filter with metallic particles in the form of longitudinal metal fibers has been known which is used for separating soot particles from the exhaust gas of diesel engines.

The present invention is based on the object to provide a device for removing solid fractions from the flue gas of internal combustion engines or industrial gas turbines, which has metallic particles and can be produced inexpensively, the filter surface of the device can be surface treated for further treatment of the exhaust gas and the device simultaneously The temperature stability for modern engines and industrial gas turbines, as they are used in power plant technology. Also, a method for surface treatment of the device according to the invention is to be created.

The invention has to solve this problem with respect to the device to the features specified in claim 1. Advantageous embodiments thereof are described in the further claims. In addition, the invention provides a method for producing a felted or felt-like metal structure according to claim 6 and a method for the surface treatment of a felted or felt-like metal structure according to claim 7.

The invention provides a device for removing solid fractions from the flue gas of internal combustion engines or industrial gas turbines, wherein the device has a structure with metallic particles and the metallic particles are connected to a felted or felt-like metal structure and arranged on a flat support structure.

The term felted or felt-like metal structure expresses that the metallic particles of the device according to the invention are in an undirected arrangement with respect to one another, whereby a large surface area provided for the flue gas filtration is achieved relative to the installation volume required by the device. In addition, this also ensures that the metallic particles required for the formation of the metal structure need not be spent with special manufacturing steps in a mutually aligned position, which reduces the manufacturing costs and is also achieved by the use of metallic particles that the inventive device the exhaust gas temperature range of Industrial gas turbines durable withstand.

It is provided according to a development of the invention that the metal structure is formed asymmetrically and the metallic particles are provided largely arranged on a cover side of the support structure. In known filter structures, a filter fleece is arranged between two cover layers, wherein the cover layers serve to protect the filter fleece and to prevent the uncontrolled escape of material from the fleece. In the apparatus according to the invention, a support structure is provided only on one side, resulting in an asymmetrical structure of the metal structure, since an uncontrolled leakage of the metallic particles from the felted metal structure composite due to the high adhesive force of the individual particles to each other is to be feared.

The metal structure can thus be formed, for example, as a mat body with the support structure on a cover side of the mat and the mat body thus formed can surround a pipe-shaped and permeable to the flue gas pipe, so that the flue gas can enter radially into the mat structure and solid particles in the cavities between the felted metallic particles can accumulate. As a result of the asymmetrical design, it is achieved that the cavities become smaller in the direction radially outward, and indeed the flue gas itself can pass through, but the solids contained therein are retained in the metal structure.

In order to achieve the asymmetric structure, it is provided according to a development of the invention that the packing density of the metal structure decreases in the direction of the support structure. The packing density is understood to mean the number of metallic particles per unit volume of the metal structure. A high number of metallic particles per unit volume ensures that the voids present between the particles are small-volume, and therefore the areas available for the passage of solids from the flue gas are small, while a lower number of metallic particles ensures that the cavities are large and therefore the penetration depth of the solids in the metal structure is large. The solid components can therefore penetrate from the support structure in the felted or felt-like metal structure, but they do not penetrate.

According to a development of the invention, it is provided that the metal structure has metallic threads and / or fibers. The threads and / or fibers can have different lengths and different diameters, so that the above-described packing density can be controlled selectively, that is, for example, threads and / or fibers with a larger diameter are arranged closer to the support structure than threads and / or fibers with a smaller diameter.

It is also provided according to a development of the invention that the metal structure comprises non-metallic filaments and / or fibers, which may be, for example, ceramic or quartz constituent filaments and / or fibers, so that the mass of the metal structure per unit volume also controlled specifically can be.

The invention also provides a method of making a felted or felt-like metal structure comprising the step of thermally sintering metallic fibers and / or filaments. By thermal sintering is achieved that the fibers and / or threads at the points at which they touch, connect with each other and so a mechanically resilient structure is created, in which the risk of loosening threads and / or fibers is reduced from the structure, so that there is no longer a need to provide a cover layer on both sides of the cover metal structure.

It is also provided according to a development of the method that a surface treatment on the felted or felt-like metal structure is carried out by a coating on the metal structure is carried out by means of a galvanic deposition and / or a coating on the metal structure by means of a physical vapor deposition is performed.

As a result, for example, a catalytic coating of the metal structure can be achieved so that the metal structure is suitable not only for particle separation from the flue gas, but also for after-treatment of the flue gas by, for example, oxidation or reduction of the nitrogen oxides in the flue gas.

According to a development of the method according to the invention, it is also provided that threads and / or fibers with a different cross-sectional area are used to form the metal structure. It is thus possible, for example, to use cross-shaped or trapezoidal threads and / or fibers in a sectional view to form the metal structure. The use of different cross-sectional areas has the advantage that thereby already a good adhesion of the individual differently shaped fibers and / or threads can be achieved before the metal structure is solidified by a thermal sintering process, since due to the different cross-sectional areas, the fibers and / or threads with each other and thus already a solid structure can be achieved.

According to a development of the method according to the invention, it is also provided that fibers and / or threads are used with a different configuration from a straight configuration. For example, like a corkscrew, helical or twisted fibers and / or filaments may be used to form the metal structure. This configuration ensures that the individual fibers and / or threads interlock with each other to form a solid structure.

It is also provided according to a development of the method according to the invention that fibers and / or threads are used with a deviating from a smooth outer contour outer contour to form the metal structure. The fibers and / or threads may, for example, be provided with scales on the outer contour or may also have a porous structure. Such a design ensures that the surface of the metal structure increases significantly compared to the surface of a metal structure formed from smooth-surfaced fibers and / or filaments, and thus increases the absorption surfaces available for the storage of the solids to be deposited.

Finally, the invention also provides an internal combustion engine having a device as described above and a catalyst device coupled to the internal combustion engine, which is characterized in that the device is arranged downstream of the internal combustion engine and upstream of the catalyst device.

Thus, the device according to the invention can be acted upon with the flue gas of the internal combustion engine as the fluidically first device in the exhaust system and thus be prevented that the catalyst device is subjected to flue gas having a large amount of solids. Such a configuration ensures that the catalyst can be made smaller than a catalyst, as it is arranged in a known manner directly fluidically in the connection of the internal combustion engine.

The invention will be explained in more detail below with reference to the drawing. This shows in:

1 a detail of a felted metal structure of an embodiment according to the present invention;

2 an enlarged view of a section "A" after 1 ;

3 Representations of different fibers and / or filaments to form the metal structure;

4 a section of a felted metal structure of another embodiment according to the present invention; and

5 a schematic representation of a structure of an internal combustion engine with an exhaust system connected, comprising the one device according to the present invention, a catalyst and a heat exchanger and a flue gas outlet.

1 The drawing shows a section of a metal structure according to an embodiment of the present invention with a closer reference to 2 the drawing enlarged detail shown "A".

The metal structure 1 has a support structure 2 , which may be, for example, a temperature-stable planar tissue. This can be, for example, a metal mesh with reinforcement wires 4 or the like.

In the drawing plane on the left side of the support structure is an asymmetric structure of fiber structure 3 arranged, which has a packing density, which in the direction of the support structure 2 decreases. The packing density is in the area with the greatest distance from the support structure 2 largest, ie the cavities located there are the smallest, while the cavities in the direction of the support structure 2 increasingly trained.

The fiber structure 3 has a similar to a felt formed structure, which is described in more detail by 2 the drawing is visible. The structure is characterized in particular by the fact that the fibers are arranged arbitrarily, without having a respectively targeted aligned course.

The one in 2 enlarged detail "A" shows a variety of metal fibers 5 which are arranged in arbitrarily aligned alignment and at enlarged connection points shown 6 touch and there are fixed to each other by means of a thermal sintering process, so that the fiber structure thus formed 3 Subsequently, for example, by means of a mechanical deformation process can be further processed, for example, can be compressed. This also allows the packing density of the metal structure 1 controlled influence.

In addition, the fiber structure 3 Also treated by means of a catalytic coating, so that in addition to the deposition of solids from the flue gas in 5 illustrated internal combustion engine 7 a further treatment of the flue gas by means of, for example, an oxidation or the reduction of nitrogen oxides is possible.

3 shows a variety of possible configurations of the fibers and / or filaments of a metal material that can be used to form the metal structure according to the invention.

As it is readily apparent, the thread can 8th have an elongated configuration with a smooth outer contour, and be circular disk-shaped in cross-section. Alternatively or additionally, threads formed similarly to a helix may also be used 9 are used, which are formed flat in a sectional view.

Also alternatively or additionally, threads may also be used 10 may be used, which are zigzag in a plan view and cross-shaped in cross-sectional view. Finally shows 3 also another embodiment of threads 11 , which are twisted together and are diamond-shaped in a cross-sectional view and also alternatively or in addition to all other forms of filaments and / or fibers can be used to form the metal structure.

4 The drawing shows a further embodiment of a metal structure 1 with a support structure 2 and a fiber structure disposed thereon 3 with a variety of zigzag threads 10 to form a filter structure 12 for the removal of solids from the flue gas of the internal combustion engine 7 , Next to the threads 10 the embodiment according to 4 also threads 8th which are elongated and formed with a smooth outer surface and as a reinforcing structure of the support structure 2 serve. Finally shows 4 also another thread 13 made of a metal material that scales on its outer surface 14 is provided and thus has a large surface and, alternatively or in addition to all in 3 The illustrated fiber forms to form the metal structure 1 can be used and due to the dandruff 14 has a large outer surface for the separation of solids from the flue gas and to form a catalytically active coated surface.

5 The drawing shows a schematic representation of an internal combustion engine 7 with a downstream immediately downstream of the engine exhaust filter 15 , which at the same time desulfurization of the flue gases of the internal combustion engine 7 serves. The desulfation can be achieved by internal engine or post-engine measures, such as a temporary forward displacement of the beginning of the fuel injection in at least one working cylinder of the internal combustion engine to provide hydrocarbons in the flue gas to achieve the required activation temperature for regeneration. Other measures are possible here.

Downstream of the exhaust filter 15 is arranged catalyst for further treatment of the flue gas, which is a heat exchanger 17 follows, over which the heat energy contained in the flue gas can be withdrawn, for example, to serve the fuel preheating or heating of buildings. Finally, the flue gas leaves the exhaust tract via a flue gas outlet 18 , Since the flue gas is already in the exhaust filter 15 can be desulfurized, it may be in the subsequent heat exchanger 17 be exposed to a much greater heat removal, as is the case with known systems, since the flue gas has already been desulfurized and therefore no longer the risk of sulfuric acid corrosion when reaching the dew point.

Since the flue gas and the solids already in the exhaust filter 15 was withdrawn, the catalyst can 16 and also the heat exchanger 17 be formed much smaller than is the case with known systems, since there is no longer a risk of clogging of the catalyst and the heat exchanger by the solid particles in the flue gas.

Due to the specific surface structure of the metal threads, such as flakes, the formation of porous surfaces by leaching, the effective surface of the metal structure can be significantly increased and thus the particle adhesion can be improved.

The metal filaments can be catalytically coated in order to be able to simultaneously carry out the emergence and oxidation of the flue gas. By a plastic deformation of the metal threads to form, for example, a waveform, the mechanical and deposition properties of the metal structure can be improved. Also, the metal structure can be post-processed by a mechanical deformation after their training, for example, to influence the packing density. By a thermal sintering process, the mechanical strength of the metal structure can be improved by the combination of different thickness and differently shaped fibers and / or filaments of metal on the one hand, the strength of the metal structure can be influenced and on the other hand, the packing density can be adjusted. Finally, it is also possible to combine non-metallic filaments and / or fibers with metallic filaments and / or fibers to form the metal structure, for example to reduce the mass of the filter structure formed with the metal structure.

In particular, not explained in more detail features of the invention, reference is otherwise expressly made to the opponent drawing.

LIST OF REFERENCE NUMBERS

1

metal structure

2

support structure

3

Fiber structure, fiber structure

4

reinforcing wire

5

metal fibers

6

junction

7

Internal combustion engine

8th

Fiber, thread

9

Fiber, thread

10

Fiber, thread

11

Fiber, thread

12

filter structures

13

Fiber, thread

14

shed

15

exhaust filter

16

catalyst

17

heat exchangers

18

Flue gas exhaust

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 112008003152 T5 [0004]

Claims (11)

Device for removing solids from the flue gas of internal combustion engines ( 7 ) or industrial gas turbines, wherein the device has a structure with metallic particles, characterized in that the metallic particles to a felted or felt-like metal structure ( 1 ) and on a flat support structure ( 2 ) are arranged. Device according to claim 1, characterized in that the metal structure ( 1 ) asymmetrically formed and the metallic particles largely on a cover side of the support structure ( 2 ) is arranged arranged. Device according to claim 1 or 2, characterized in that the packing density of the metal structure ( 1 ) towards the support structure ( 2 ) decreases. Device according to one of the preceding claims, characterized in that the metal structure ( 1 ) metallic threads ( 8th . 9 . 10 . 11 . 13 ) and / or fibers ( 8th . 9 . 10 . 11 . 13 ) having. Device according to one of the preceding claims, characterized in that the metal structure ( 1 ) has non-metallic threads and / or fibers. Process for producing a felted or felt-like metal structure, characterized by the step of thermal sintering of metallic fibers ( 8th . 9 . 10 . 11 . 13 ) and / or threads ( 8th . 9 . 10 . 11 . 13 ). A method according to claim 6, characterized by at least one of the subsequent steps for the surface treatment of a felted or felt-like metal structure ( 1 ): - applying a coating to the metal structure ( 1 ) by means of a galvanic deposition - application of a coating on the metal structure ( 1 ) by means of physical vapor deposition. Method according to claim 6 or 7, characterized by the use of fibers ( 8th . 9 . 10 . 11 . 13 ) and / or threads ( 8th . 9 . 10 . 11 . 13 ) with different cross-sectional area. Method according to one of claims 6 to 8, characterized by the use of fibers ( 8th . 9 . 10 . 11 . 13 ) and / or threads ( 8th . 9 . 10 . 11 . 13 ) having a configuration different from a straight configuration. Method according to one of claims 6 to 9, characterized by the use of fibers ( 8th . 9 . 10 . 11 . 13 ) and / or threads ( 8th . 9 . 10 . 11 . 13 ) with a deviating from a smooth outer contour outer contour. Internal combustion engine ( 7 ) with a device according to one of claims 1 to 5 and one with the internal combustion engine ( 7 ) coupled catalyst device ( 15 ), characterized in that the device downstream of the internal combustion engine ( 7 ) and upstream of the catalyst device ( 15 ) is arranged.

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