WO2022233569A1

WO2022233569A1 - Filter element for hot gas filtration

Info

Publication number: WO2022233569A1
Application number: PCT/EP2022/060275
Authority: WO
Inventors: Andreas Stephan; Stephan Buckenhüskes; Marcus Wegmann; Fabian HEUZEROTH
Original assignee: Hengst Se
Priority date: 2021-05-03
Filing date: 2022-04-19
Publication date: 2022-11-10
Also published as: DE102021111390A1

Abstract

The invention relates to a filter element (10) for hot gas filtration, comprising at least one folded filter medium (12) which extends in a peripheral direction, and at least one joining element (14a, 14b), wherein an end face-side end portion (20a, 20b) of the filter medium (12) is adhered to the joining element (14a, 14b) by a silicone-containing adhesive (24a, 24b).

Description

Filter element for hot gas filtration

The invention relates to a filter element for hot gas filtration, having at least one pleated filter medium extending in the circumferential direction and at least one joined body.

Furthermore, the invention relates to a hot gas filtration system with a plurality of filter elements for hot gas filtration.

In addition, the invention relates to a method for producing a filter element for hot gas filtration.

In a variety of applications it is necessary to filter hot process or combustion gases laden with particles in order to remove the particles from a gas flow. In large-scale plants in particular, comparatively long filter hoses are used in this context, which have a temperature-resistant textile filter medium. The filter medium of corresponding filter hoses is usually welded or sewn. Due to the smooth cylindrical shape of the filter medium, filter hoses several meters long are often required in order to be able to implement an intended hot gas filtration. Corresponding filter hoses therefore require a comparatively large amount of space and are expensive to install and maintain. In the case of impulse cleaning, large amounts of air are also required per pressure impulse, so that the operating costs of a corresponding system are comparatively high. Compact filter elements with pleated filter media can be used to reduce the space required. This usually also leads to simplified assembly and shorter downtimes when changing the filter. In addition, a considerable amount of scavenging air can be saved with impulse cleaning, resulting in a reduction in operating costs. In this context, however, there is the problem that the joint connection between the folded filter medium and the cover or base of the filter element has hitherto not been sufficiently thermally resilient for high-temperature applications. The polyurethane adhesives used to bond the folded filter medium to the cover or bottom of the filter element cannot withstand the thermal, chemical and mechanical stresses that occur during pulse cleaning in the long term.

In order to be able to do without a corresponding adhesive bond, publication WO 2015/160608 A1 proposes a filter element whose end cap is made of a temperature-resistant silicone material. However, the problem with these and other solutions for attaching pleated filter media for hot gas filtration is that a comparatively large amount of temperature-resistant silicone material is required to attach the pleated filter media via the silicone end cap. A filter-specific silicone end cap is also required, so the filter lids and bottoms used in low-temperature applications cannot be used.

The object on which the invention is based is therefore to enable hot gas filtration with a filter element which can be produced comparatively inexpensively on the basis of filter element components from other areas of application.

The object is achieved by a filter element of the type mentioned at the outset, with a front end section of the filter medium of the filter element according to the invention being bonded to the joining body by means of a silicone-containing adhesive. The invention makes use of the finding that by using a silicone-containing adhesive, joining bodies, for example filter covers or filter bases, can be used which are also installed in filter elements from other areas of application. The filter element according to the invention can therefore be used as a hose replacement element for high-temperature applications. Due to the folding of the filter medium, the filter element can be made about two-thirds shorter than a bag filter without reducing the filter surface. The more compact design of the filter element also results in simplified assembly, so that downtimes when changing the filter are reduced. Appropriate filter elements can also be retrofitted to existing hot gas filtration systems. Due to the compact design of the filter element, a significantly smaller amount of scavenging air is required when cleaning the filter element than is the case with bag filters. By saving flushing air, a corresponding hot gas filtration system causes significantly lower operating costs. When building new hot gas filtration systems, significantly more compact filter housings can also be planned, so that the material and construction costs are reduced.

A corresponding bonding of the filter medium with the joint body was previously not possible in high-temperature applications due to the lack of temperature resistance of the adhesives used. The silicone-containing adhesive of the filter element according to the invention is also suitable for high-temperature applications, i. H. replaceable at process temperatures above 160 degrees Celsius and maximum temperatures of up to 300 degrees Celsius. Even at temperatures above 160 degrees Celsius, the silicon-based adhesive remains flexible enough to absorb shocks from several thousand cleaning pulses without being damaged.

The filter medium is preferably formed from a fibrous material. In the dry state, the fiber material of the filter medium can have a toughness or strength in the range from 35 cN/tex to 40 cN/tex, in particular a toughness or strength of 38 cN/tex. Furthermore, the fiber material of the Filter medium have an elongation at break in the range of 25% to 35%, in particular an elongation at break of 30%. The fiber material of the filter medium is preferably designed in such a way that it shrinks by less than 4%, in particular by less than 3%, at 240° C. for 15 minutes. The density of the fibrous material of the filter medium is preferably in a range from 1.3 g/cm ³ to 1.5 g/cm ³ , in particular the density is 1.41 g/cm ³ : the fibrous material of the filter medium is preferably designed in such a way that at 60% rel. humidity and 20° C a

Moisture gain in the range of 2% to 4%, in particular a moisture gain of 3%. The filter medium can be a P84

Filter media or a P84-HT filter media. In addition to fibers made of polyimide (PI), the filter medium can also include fibers made of polytetrafluoroethylene (PTFE) and/or glass fibers. The filter medium can include a supporting wire mesh for stabilization, or have a temperature-resistant impregnation. Furthermore, the filter medium can be stabilized by thermal pretreatment.

The joined body of the filter element can be a filter cover or a filter bottom. Furthermore, the joining body can be made of metal or a metal alloy. The joining body can also be made of galvanized material. In particular, the joining body is made of stainless steel. The filter element can also have an internal support structure, with the filter medium running around the internal support structure. The inner support structure is preferably designed as an inner dome of the filter element.

In a preferred embodiment of the filter element according to the invention, the joining body has an at least partially circumferential

Receiving gap, in which the glued to the joint body end portion of the filter medium and / or the silicone-containing adhesive is arranged. The wall of the joining body delimiting the receiving gap can have a U-shaped cross section. The wall of the joining body that delimits the receiving gap preferably has a bottom surface facing the filter medium, an inner wall that extends vertically upwards from the bottom surface and runs at least partially around the circumference and/or a from the bottom surface extending vertically upwards and at least partially circumferential outer wall. The inner wall and the outer wall preferably run around a common central axis. During manufacture of the filter element, the adhesive is applied in the flowable state into the receiving gap before the front end section of the filter medium is inserted into the receiving gap or after the front end section of the filter medium has been inserted into the receiving gap.

In a further development of the filter element according to the invention, the joined body comprises a bottom surface which is arranged on the face side of the filter medium. An end face of the filter medium is bonded to the bottom face of the joined body by means of the silicone-containing adhesive. The silicone-containing adhesive is preferably located between the bottom surface of the joint body and the front surface of the filter medium. In particular, the silicone-containing adhesive forms an adhesive layer which is arranged between the bottom surface of the joined body and the front surface of the filter medium.

In addition, a filter element according to the invention is advantageous in which the joining body comprises an at least partially peripheral outer wall which runs around the front end section of the filter medium. Fold segments of the filter medium located in the front end section are preferably bonded by means of the silicone-containing adhesive to a surface of the outer wall of the joined body that faces the filter medium. The silicone-containing adhesive is preferably located in spaces between successive or adjacent folds of the filter media. The fact that the silicone-containing adhesive is in the spaces between the folds of the filter medium increases the contact surface between the adhesive and the filter medium, which further increases the adhesive effect and thus the load-bearing capacity of the adhesive connection.

In a further preferred embodiment of the filter element according to the invention, the surface of the outer wall facing the filter medium approaches the filter medium in the axial direction. The distance between the filter medium preferably changes in the axial direction facing surface of the outer wall of the joining body and the

filter medium. The surface of the outer wall facing the filter element runs, for example, in the manner of a truncated cone towards the joining body. the

Outer wall can taper in the axial direction. An undercut preferably results, which additionally secures the joined body to the filter medium, so that a secure connection is ensured even under heavy stress and overload.

A filter element according to the invention is also advantageous in which the joining body comprises an at least partially circumferential inner wall which extends along the inner contour of the front end section of the filter medium. Fold segments of the filter medium located in the front end section are preferably bonded by means of the silicone-containing adhesive to a surface of the inner wall of the joined body that faces the filter medium. The silicone-containing adhesive is preferably located in spaces between successive or adjacent folds of the filter media.

In a further embodiment of the filter element according to the invention, the surface of the inner wall facing the filter medium approaches the filter medium in the axial direction. Consequently, the distance between the surface of the inner wall of the joined body facing the filter medium and the filter medium changes in the axial direction. The surface of the inner wall facing the filter medium runs towards the filter medium in the manner of a truncated cone, for example. The inner wall can taper in the axial direction. An undercut preferably results, which additionally secures the joined body to the filter medium, so that a secure connection is ensured even under heavy stress and overload.

In a further development of the filter element according to the invention, the joining body has a fixing web which extends in the radial direction and runs at least partially around the circumference, on which the silicone-containing adhesive rests or which is embedded in the silicone-containing adhesive. An at least partially encircling adhesion chamber for the adhesive is created by the fixing web. The adhesion chamber increases the contact surface between the joining body and the adhesive and thus increases the strength of the adhesive bond. The fixing web ensures mechanical clamping of the adhesive and acts as a stop body for the dried adhesive body. The fixing web can extend radially inwards from a peripheral outer wall. The fixing web can extend radially outwards from a peripheral inner wall. The joining body can have one or more inner fixing webs and/or one or more outer fixing webs, it being possible for an inner fixing web and an outer fixing web to be arranged opposite one another, for example. Alternatively, an inner fixing bar and an outer fixing bar can run in planes that are spaced apart from one another. One or more fixing webs can be integral components of the inner wall of the joint body. One or more fixing webs can be integral components of the outer wall of the joined body. The one or more fixing webs can each produce an undercut, which additionally secures the joined body to the filter medium, so that a secure connection is ensured even under heavy stress and overload. A fixing web can also be realized via a separate fixing disk or fixing plate of the joining body. The joining body can be designed in one piece or in multiple pieces. In a further embodiment, the filter element according to the invention has a first joining body and a second joining body. A first end section of the filter medium at the end is preferably bonded to the first joining body by means of the silicone-containing adhesive. A second front end section of the filter medium is preferably bonded to the second joining body by means of the silicone-containing adhesive. A joined body can have a recess through which hot gas that has flowed from the raw gas side of the filter element through the filter medium to the clean gas side of the filter element can be discharged from the filter element. A joining body can be designed as a cover, which is designed to close an opening of the filter medium in a front end section in such a way that an inflow of unfiltered hot gas from the raw gas side to the clean gas side of the filter element through the opening of the filter medium is avoided. Between the first joining body and the second joining body can To increase stability, temperature-stable metal clamps, stainless steel cable ties or metal bands, which run around the filter medium, can be arranged.

A filter element according to the invention which has a first filter medium and a second filter medium is also advantageous. A front end section of the first filter medium is glued to the joining body on a first side of the joining body by means of the silicone-containing adhesive. A front end section of the second filter medium is bonded to the joint body on a second side of the joint body by means of the silicone-containing adhesive. The joining body consequently serves as a connecting element for connecting two filter media. The joined body thus has a double flange for accommodating two filter media. In this case, the joining body can be in one piece or in several pieces. If the joining body is designed in several parts, a first joining body part is preferably glued to a front end section of a first filter medium and a second joining body part is glued to a front end section of a second filter medium. The joining body parts can be end disks that are fastened to one another or joined to one another. The joining body parts can be welded to one another, glued to one another or mechanically joined. In particular, the joining body parts are tightly connected to one another. The filter element can have further joining bodies and filter media, which are connected to one another by means of the silicone-containing adhesive. The joining body preferably has a recess which connects the inner regions of the first and second filter medium to one another. Filter elements with excess length and so-called stack filters can be realized with a corresponding joining body. In a development of the filter element according to the invention, the silicone-containing adhesive comprises polysiloxane. In particular, the adhesive is a polysiloxane adhesive. Polysiloxane adhesives remain flexible at temperatures above 160 degrees Celsius, preventing damage or degradation of the adhesive bond even in high temperature applications. In a further preferred embodiment of the filter element according to the invention, the silicone-containing adhesive has a Shore A hardness of between 35 and 60. The adhesive preferably has a Shore A hardness of 50. Furthermore, the silicone-containing adhesive preferably has an elongation at break of between 200% and 450%. In particular, the silicone-containing adhesive has an elongation at break of 300%. The tensile strength of the silicone-containing adhesive is between 2.0 and 3.0 N/mm ² , for example. In particular, the tensile strength of the adhesive is 2.6 N/mm ² .

The object on which the invention is based is also achieved by a hot gas filtration system of the type mentioned at the beginning, wherein a filter element, several or all filter elements of the hot gas filtration system according to the invention are designed according to one of the embodiments described above. With regard to the advantages and modifications of the hot gas filtration system according to the invention, reference is first made to the advantages and modifications of the filter element according to the invention.

The hot gas filtration system can have a pressure pulse cleaning function. The filter elements of the hot gas filtration system preferably run parallel to one another and are arranged at a distance from one another.

The object on which the invention is based is also achieved by a method of the type mentioned at the outset, in which, within the scope of the method according to the invention, a flowable silicone-containing adhesive is applied to an application area of a joining body and a front end section of a folded filter medium extending in the circumferential direction is inserted into the application area of the joining body becomes. A filter element according to one of the embodiments described above is preferably produced by means of the method according to the invention. With regard to the advantages and modifications of the method according to the invention, reference is first made to the advantages and modifications of the filter element according to the invention. The adhesive can be applied to the application area before, during and/or after the insertion of the front end section of the filter medium into the application area. After the front end section of the filter medium has been inserted into the application area or after the adhesive has been applied to the application area, the silicone-containing adhesive hardens and joins the filter medium to the joint body. The surfaces in the application area can be cleaned, degreased, coated and/or roughened before the adhesive is applied.

In a preferred embodiment of the method according to the invention, the application area extends along an at least partially circumferential receiving gap of the joining body. The free-flowing silicone-based adhesive is then applied into the receiving gap of the joint body. The receiving gap is preferably delimited by a peripheral inner wall and/or by a peripheral outer wall. This effectively prevents the free-flowing adhesive from unintentionally running off after it has been applied to the application area.

In a further preferred embodiment of the method according to the invention, when the front end section of the filter medium is inserted into the application area of the joining body, adhesive present in the application area is displaced from the filter medium in such a way that it flows into spaces between adjacent folds of the filter medium. The contact surface between the adhesive and the filter medium is thus increased and the resilience and strength of the subsequent adhesive connection is increased. Even after the filter medium has been inserted, there is a quantity of adhesive between an end face of the filter medium and a bottom face of the joined body.

In a preferred embodiment of the method according to the invention, when the front end section of the filter medium is inserted into the application area of the joining body, the adhesive present in the application area is displaced from the filter medium in such a way that it flows into an at least partially circumferential adhesion chamber, so that there is a build-up in the adhesion chamber at least partially circumferential adhesive collar results. The hardened adhesive collar ensures that the filter medium is jammed in the joint body, so that the load-bearing capacity of the adhesive connection is further increased. In addition, the contact area between the joining body and the adhesive is increased by the adhesion chamber, as a result of which the adhesive effect is further improved.

Preferred embodiments of the invention are explained and described in more detail below with reference to the accompanying drawings. 1 shows an exemplary embodiment of the filter element according to the invention in a schematic sectional view;

2 shows a joined body of a filter element according to the invention in a schematic sectional view;

3 shows a further joined body of a filter element according to the invention in a schematic sectional view;

4 shows a further joined body of a filter element according to the invention in a schematic sectional view;

5 shows a further joined body of a filter element according to the invention in a schematic sectional view; 6 shows an exemplary embodiment of the filter element according to the invention in a schematic sectional representation; and

7 shows an embodiment of the invention

Hot gas filtration system in a schematic representation.

1 shows a filter element 10 which is suitable for the filtration of hot gas. Consequently, the filter element 10 is suitable for the filtration of gases with temperatures in excess of 160 degrees Celsius. The filter element 10 has a pleated filter medium 12 extending in the circumferential direction, which separates a raw gas side 16 from a clean gas side 18 . The filter medium 12 can be formed from a fibrous material. For example, the filter media 12 is a P84 filter media or a P84-HT filter media. The filter media 12 may include polyimide (PI) fibers, polytetrafluoroethylene (PTFE) fibers, and/or glass fibers. Furthermore, the filter medium can have a supporting wire mesh and/or include a temperature-resistant impregnation.

The filter medium 12 is arranged between two joining bodies 14a, 14b, it being possible for the joining bodies 14a, 14b to be made of metal or a metal alloy. The joining body 14a is a lower end disk. The joining body 14b is an upper end plate. The joining bodies 14a, 14b each have a circumferential receiving gap 22a, 22b. A front end section 20a of the filter medium 12 is arranged in the receiving gap 22a of the joining body 14a. A front end section 20b of the filter medium 12 is arranged in the receiving gap 22b of the joining body 14b. The front end sections 20a, 20b of the filter medium 12 are bonded to the joining bodies 14a, 14b by means of a silicone-containing adhesive 24a, 24b. The silicone-containing adhesive 24a is located in the circumferential receiving gap 22a of the joining body 14a. The silicone-containing adhesive 24b is located in the circumferential receiving gap 22b of the joining body 14b. The silicone-containing adhesive 24a, 24b is thus a polysiloxane adhesive. Furthermore, the silicone-containing adhesive 24a, 24b has a Shore A hardness of between 35 and 60, an elongation at break of between 200% and 450% and a tensile strength of between 2.0 and 3.0 N/mm ² . The silicone-containing adhesive 24a, 24b is sufficiently flexible, even at temperatures above 160 degrees Celsius, to be able to absorb shocks from several thousand cleaning pulses without being damaged. Thus, the filter element 10 shown can be used in a hot gas filtration system 100 with a pressure pulse cleaning function. A wall 26a of the joining body 14a delimiting the receiving gap 22a and a wall 26b of the joining body 14b delimiting the receiving gap 22b each have a U-shaped cross section. The walls 26a, 26b the joining bodies 14a, 14b each have a bottom surface 28a, 28b facing the filter medium 12. An inner wall 34a, 34b and an outer wall 32a, 32b extend perpendicularly from the bottom surfaces 28a, 28b. The inner walls 34a, 34b and the outer walls 32a, 32b run around a common central axis X. An end face 30a of the filter medium 12 is bonded to the bottom face 28a of the joined body 14a by means of the silicone-containing adhesive 24a. An end face 30b of the filter medium 12 is bonded to the bottom face 28b of the joining body 14b by means of the silicone-containing adhesive 24b. Between the bottom surfaces 28a, 28b of the joining bodies 14a, 14b and the front surfaces 30a, 30b of the filter medium 12 there is in each case a silicone-containing adhesive layer.

The outer walls 32a, 32b run around the front end sections 20a, 20b of the filter medium 12. The inner walls 34a, 34b extend along an inner contour of the front end sections 20a, 20b of the filter medium 12. The fold segments of the filter element 12 located in the front end sections 20a, 20b are surfaces of the outer walls facing the filter medium 12 by means of the silicone-containing adhesive 24a, 24b 32a, 32b and with the filter medium 12 facing surfaces of the inner walls 34a, 34b of the joining body 14a, 14b bonded. The silicone-containing adhesive 24a, 24b is also located in spaces between adjacent folds of the filter medium 12. The joining body 14a has a plurality of circumferential fixing webs 36a-36c extending in the radial direction. The joining body 14b also has a plurality of circumferential fixing webs 38a-38c extending in the radial direction. The fixing webs 36a-36c, 38a-38c are embedded in the silicone-containing adhesive 24a, 24b. Through the fixing bars

36a-36c, 38a-38c circumferential adhesion chambers 48a, 48b are created for the adhesive 24a, 24b. The fixing webs 36a, 36b extend radially outwards from the peripheral inner wall 34a. The fixing web 36c extends radially inwards from the peripheral outer wall 32a. The fixing webs 38a, 38b extend radially outwards from the peripheral inner wall 34b. The fixing web 38c extends radially inwards from the peripheral outer wall 32b. The joining body 14a thus has two inner fixing webs 36a, 36b and an outer fixing web 36c. The joining body 14b also has two inner fixing webs 38a, 38b and an outer fixing web 38c. The fixing webs 36a-36c, 38a-38c ensure mechanical clamping of the adhesive 24a, 24b and act as a stop body for implementing an axial stop. The fixing webs 36a-36c are integral components of the wall 26a of the joining body 14a. The fixing webs 38a-38c are integral components of the wall 26b of the joining body 14b. Undercuts are produced via the fixing webs 36a-36b, 38a-38c, which additionally secure the joining bodies 14a, 14b to the filter medium 12, so that a secure connection is ensured even under heavy stress and overload.

The joined body 14b has a recess 40b through which hot gas that has flowed from the raw gas side 16 of the filter element 10 through the filter medium 12 to the clean gas side 18 of the filter element 10 can be discharged from the filter element 10 . Joining body 14a is designed as a cover which is designed to close a central opening in filter medium 12 in the area of front end section 20a in such a way that unfiltered hot gas can flow from raw gas side 16 onto clean gas side 18 of filter element 10 through the opening of the Filter medium 12 is avoided.

2 shows a one-piece joining body 14 made of metal with a wall 26. The surface of the outer wall 32 facing the filter medium (not shown) approaches the filter medium 12 in the axial direction. The distance between the surface of the outer wall 32 of the joining body 14 facing the filter medium 12 and the filter medium 12 changes in the axial direction. An undercut results, which additionally secures the joining body 14 to the filter medium 12, so that a secure connection is ensured even under heavy stress and overload.

To produce a filter element 10, flowable silicone-containing adhesive is applied to an application area 42 of the joining body 14 and a front end section of a folded element extending in the circumferential direction The filter medium 12 is inserted into the application area 42 of the joined body 14 . The application area 42 extends along a circumferential receiving gap 22 of the joining body 14.

3 shows a multi-part joining body 14 with a base body 44 and a fixing disk 46 connected to the base body 44. The base body 44 and the fixing disk 46 can be screwed, welded or connected to one another in some other way. In a radial outer area, the fixing disk 46 has a material edge that is bent upwards. Between the material edge of the fixing disc 46, which is bent upwards, and the wall 26 of the base body 44, there extends a peripheral adhesive chamber 48, into which adhesive can also be applied for fastening a filter medium 12. As an alternative or in addition to the direct application of adhesive into the adhesion chamber 48 , the adhesive can also flow into the adhesion chamber 48 as a result of material displacement when the filter medium 12 is inserted into the application area 42 . The adhesive in the adhesive chamber 48 forms a circumferential adhesive collar, which leads to a further increase in the load-bearing capacity of the adhesive connection.

4 shows a joining body 16 in which the peripheral inner wall 34 has a peripheral fixing web 36 . In combination with the outer wall 32 directed obliquely inward, an undercut on the inside and an undercut on the outside result, with both undercuts being provided for receiving adhesive containing silicone. The undercut construction results in additional clamping of the adhesive within the receiving gap 22. FIG. 5 shows a joined body in which the surface of the inner wall 34 facing the filter medium 12 approaches the filter medium (not shown) in the axial direction. The outer wall 32 and the inner wall 34 are consequently tilted in the direction of the receiving gap 22 so that an undercut on the inside and an undercut on the outside again result. The undercuts ensure that the adhesive is jammed within the receiving gap 22. FIG. 6 shows a filter element 10 which is designed as a so-called stack filter. The filter element 10 has three joined bodies 14a-14c and two filter media 12a, 12b. The filter medium 12a is arranged between the joining bodies 14a, 14b. The filter medium 12b is arranged between the joining bodies 14b, 14c.

The front end section 20a of the filter medium 12a is located in a receiving gap 22a of the joining body 14a and is bonded to the joining body 14a by means of the silicone-containing adhesive 24a. The front end section 20b of the filter medium 12a is located in a receiving gap 22b of the joining body 14b and is bonded to the joining body 14b by means of the silicone-containing adhesive 24b. The front end section 20c of the filter medium 12b is located in a receiving gap 22c of the joining body 14b and is bonded to the joining body 14b by means of the silicone-containing adhesive 24c. The front end section 20d of the filter medium 12b is located in a receiving gap 22d of the joining body 14c and is bonded to the joining body 14c by means of the silicone-containing adhesive 24d.

The front end section 20b of the filter medium 12a is glued to the joining body 14b on a first side of the latter, and the front end section 20c of the filter medium 12b is glued to the joining body 14b on a second side thereof. The joining body 14b consequently serves as a connecting element for connecting two filter media 12a, 12b. The joining body 14b has a recess 40b which connects the inner regions of the filter media 12a, 12b to one another. Filter elements 10 with excess length can thus be realized via corresponding joining bodies 14a-14c. The joined body 14c has a recess 40c through which filtered hot gas can be discharged from the filter element 10 .

7 shows a hot gas filtration system 100 with a plurality of filter elements 10a-10e. The filter elements 10a-10e are designed for hot gas filtration. The hot gas loaded with particles flows into the hot gas filtration system 100 via the raw gas inlet 102 . The filtration takes place through the filter elements 10a-10e, through which the hot gas flows. The filtered hot gas leaves the hot gas filtration system 100 through the clean gas outlet 104.

The hot gas filtration system 100 has a number of cleaning devices 106a-106e, via which a pressure pulse cleaning function can be implemented. Compressed air can be introduced into the filter elements 10a-10e in pulses from the clean gas side via the cleaning devices 106a-106e. The particles adhering to the filter media of the filter elements 10a-10e, which were previously filtered out of the hot gas flow, are released from the filter media of the filter elements 10a-10e by the compressed air pulses and can be removed from the hot gas filtration system 100 via the funnel 108.

The filter media of the filter elements 10a-10e are each glued in the respective filter element 10a-10e via a silicone-containing adhesive.

Reference sign

10, 10a-10e filter elements 12, 12a, 12b filter media 14, 14a-14c joined body

16 raw gas side 18 clean gas side

20a-20d end portions 22, 22a-22d receiving gaps 24a-24d adhesive 26, 26a, 26b walls 28, 28a, 28b bottom surfaces 30a, 30b end surfaces 32, 32a, 32b outer walls 34, 34a, 34b inner walls

36, 36a-36c fixing webs 38a-38c fixing webs 40b, 40c recesses 42 application area 44 base body

46 fixing disc

48, 48a, 48b detention chambers

100 hot gas filtration system 102 raw gas inlet

104 clean gas outlet

106a-106e cleaning devices

108 funnel X central axis

Claims

Expectations

1. Filter element (10, 10a-10e) for hot gas filtration, with at least one pleated filter medium (12, 12a, 12b) extending in the circumferential direction, and at least one joining body (14, 14a-14c), characterized in that a front end section ( 20a-20d) of the filter medium (12, 12a, 12b) is bonded to the joint body (14, 14a-14c) by means of a silicone-containing adhesive (24a-24d).

2. Filter element (10, 10a-10e) according to claim 1, characterized in that the joining body (14, 14a-14c) has an at least partially circumferential receiving gap (22, 22a-22d), in which the jointed body (14, 14a-14c) glued front end section (20a-20d) of the filter medium (12, 12a, 12b) and/or the silicone-containing adhesive (24a-24d) is arranged.

3. Filter element (10, 10a-10e) according to claim 1 or 2, characterized in that the joining body (14, 14a-14c) comprises a bottom surface (28, 28a, 28b) which frontally from the

Filter medium (12, 12a, 12b) is arranged, wherein an end face (30a, 30b) of the filter medium (12, 12a, 12b) by means of the silicone-containing adhesive (24a-24d) with the bottom surface (28, 28a, 28b) of the joined body ( 14, 14a- 14c) is glued.

4. Filter element (10, 10a-10e) according to one of the preceding claims, characterized in that the joining body (14, 14a-14c) comprises an at least partially circumferential outer wall (32, 32a, 32b) which is wrapped around the end section (20a -20d) of the filter medium (12, 12a, 12b), with fold segments of the filter medium (12, 12a, 12b) located in the front end section (20a-20d) preferably being bonded by means of the silicone-containing adhesive (24a-24d) with a dem Filter medium (12, 12a, 12b) facing surface of the outer wall (32, 32a, 32b) of the joint body (14, 14a-14c) are glued.

5. The filter element (10, 10a-10e) according to claim 4, characterized in that the surface of the outer wall (32, 32a, 32b) facing the filter medium (12, 12a, 12b) faces the filter medium (12, 12a, 12b ) approximates.

6. Filter element (10, 10a-10e) according to one of the preceding claims, characterized in that the joining body (14, 14a-14c) comprises an at least partially circumferential inner wall (34, 34a, 34b) which extends along an inner contour of the end-side End section (20a- 20d) of the filter medium (12, 12a, 12b), wherein in the end section (20a-20d) located fold segments of the filter medium (12, 12a, 12b) preferably by means of the silicone-containing

Adhesive (24a-24d) are bonded to a surface of the inner wall (34, 34a, 34b) of the joined body (14, 14a-14c) that faces the filter medium (12, 12a, 12b).

7. Filter element (10, 10a-10e) according to claim 6, characterized in that the surface of the inner wall (34, 34a, 34b) facing the filter medium (12, 12a, 12b) faces the filter medium (12, 12a, 12b) approximates.

8. Filter element (10, 10a-10e) according to one of the preceding claims, characterized in that the joining body (14, 14a-14c) has a fixing web (36, 36a-36c, 38a-38c) extending in the radial direction and at least partially encircling. has, on which the silicone-containing adhesive (24a-24d) rests or which is embedded in the silicone-containing adhesive (24a-24d).

9. Filter element (10, 10a-10e) according to any one of the preceding claims, characterized by a first joining body (14a) and a second joining body (14b), wherein a first front end section (20a) of the filter medium (12) is bonded to the first joining body (14a) by means of the silicone-containing adhesive (24a) and a second front end section (20b) of the filter medium (12) by means of the silicone-containing

Adhesive (24b) is bonded to the second joining body (14b).

10. Filter element (10, 10a-10e) according to any one of the preceding claims, characterized by a first filter medium (12a) and a second filter medium (12b), wherein a front end portion (20b) of the first

filter medium (12a) on a first side of the joining body (14b) is bonded to the joining body (14b) by means of the silicone-containing adhesive (24b) and a front end section (20c) of the second filter medium (12b) on a second side of the joining body (14b) is bonded to the joining body (14b) by means of the silicone-containing adhesive (24c).

11. Filter element (10, 10a-10e) according to one of the preceding claims, characterized in that the silicone-containing adhesive (24a-24d) comprises polysiloxane.

12. Filter element (10, 10a-10e) according to one of the preceding claims, characterized in that the silicone-containing adhesive (24a-24d) has a Shore hardness A between 35 and 60; an elongation at break between 200% and 450%; and/or - has a tensile strength of between 2.0 and 3.0 N/mm ² .

13. Hot gas filtration system (100), with a plurality of filter elements (10, 10a-10e) for hot gas filtration; characterized in that a filter element (10, 10a-10e), several or all filter elements (10, 10a-10e) are designed according to one of the preceding claims.

14. A method for producing a filter element (10, 10a-10e) for hot gas filtration, in particular a filter element (10, 10a-10e) according to any one of claims 1 to 12, characterized by the steps of: - applying a free-flowing silicone-containing adhesive (24a-24d ) in an application area (42) of a joining body (14, 14a-14c), and inserting a front end section (20a-20d) of a pleated filter medium (12, 12a, 12b) extending in the circumferential direction into the application area (42) of the joining body ( 14, 14a-14c).

15. The method according to claim 14, characterized in that the application area (42) extends along an at least partially circumferential receiving gap (22, 22a-22d) of the joining body (14, 14a-14c).

16. The method according to claim 14 or 15, characterized in that when inserting the front end section (20a-20d) of the filter medium (12, 12a, 12b) in the application area (42) of the joined body (14, 14a-14c) in the application area (42) existing adhesive (24a-24d) such from the

Filter medium (12, 12a, 12b) is displaced in that it flows into spaces between adjacent folds of the filter medium (12, 12a, 12b).

17. The method according to any one of claims 14 to 16, characterized in that when inserting the front

end section (20a-20d) of the filter medium (12, 12a, 12b) in the application area (42) of the joining body (14, 14a-14c) adhesive (24a-24d) present in the application area (42) in such a way from the filter medium (12, 12a, 12b) is displaced so that it flows into an at least partially circumferential adhesion chamber (48, 48a, 48b), so that in the

Adhesive chamber (48, 48a, 48b) results in an at least partially circumferential adhesive collar.