EP3277936A1

EP3277936A1 - Catalytic converter unit and exhaust gas catalytic converter

Info

Publication number: EP3277936A1
Application number: EP16711639.1A
Authority: EP
Inventors: Andreas Döring; Martin Faber; Richard Losher; Francis NANA
Original assignee: MAN Diesel and Turbo SE
Current assignee: MAN Energy Solutions SE
Priority date: 2015-03-30
Filing date: 2016-03-23
Publication date: 2018-02-07
Also published as: US10400655B2; DE102015219827A1; US20180094567A1; KR101943785B1; CN107429596B; JP6513824B2; JP2018514682A; KR20170134543A; WO2016156163A1; CN107429596A

Abstract

Catalytic converter unit (10) for an exhaust gas catalytic converter, in particular an SCR catalytic converter unit for an SCR catalytic converter of a marine diesel internal combustion engine, with multiple catalytic converter modules (11), wherein each catalytic converter module (11) has a ceramic catalytic converter body through which exhaust gas flows and a metallic casing (12) for the ceramic catalytic converter body, wherein the respective ceramic catalytic converter body is received in the respective metallic casing (12) and is surrounded in certain sections by the latter, wherein the catalytic converter modules (11) are positioned with first flowed-through ends on a support grating (13), wherein a counter-brace (14) is positioned at the opposite second flowed-through ends of the catalytic converter modules (11), and wherein the catalytic converter modules (11) are clamped between the support grating (13) and the counter-brace (14).

Description

Catalyst unit and catalytic converter

The invention relates to a catalyst unit according to the preamble of claim 1. Furthermore, the invention relates to an exhaust gas catalyst.

A catalyst unit for an exhaust gas catalyst has a plurality of catalyst modules. Each catalyst module has a ceramic catalyst body through which exhaust gas flows and via a metallic, rectangular cross-section housing for the ceramic catalyst body, wherein the housing is also referred to as Canning. The housing of the respective catalyst module accommodates the respective catalyst body and surrounds it in sections, namely with the ends of the catalyst body flowed through, one end through which provides an inflow end and the other end through which flows provides an outflow end of the respective catalyst body.

In catalyst units known from practice, the catalyst modules are arranged in the form of arrays in the form of a plurality of rows and columns, wherein immediately adjacent catalyst modules in the region of their metallic, rectangular in cross-section housing, in particular by welding, are firmly connected. Then, when a catalyst module is to be replaced in a catalyst unit, these welded joints must be released by flexing, for example, whereby adjacent catalyst modules may be damaged. The connection of adjacent catalyst modules by welding is therefore disadvantageous.

There is therefore a need for a catalyst unit for a catalyst in which catalyst modules can be exchanged more easily. On this basis, the present invention has the object to provide a novel catalyst unit for an exhaust gas catalyst and an exhaust gas catalyst with such a catalyst unit.

This object is achieved by a catalyst unit according to claim 1. According to the invention, the catalyst modules are positioned with first through-flowed ends on a support grid, wherein a counter-holder is positioned at the opposite second through-flow ends of the catalyst modules, and wherein the catalyst modules are clamped between the support grid and the counter-holder. The invention allows a simple, easy replacement of catalyst modules of a catalyst unit without a risk of damage to adjacent catalyst modules.

According to an advantageous embodiment, the support grid a plurality of mutually parallel first support struts and a plurality of also parallel to each other and perpendicular to the first support struts extending second support struts on which the catalyst modules are positioned. Preferably, a sealing element is positioned between directly parallel support struts of the support grid, on which directly adjacent catalyst modules are positioned, which prevents an exhaust gas flow between the housings of the adjacent catalyst modules. Immediately parallel support struts preferably provide an individual tolerance compensation for the respective directly adjacent catalyst modules. This embodiment of the catalyst unit is particularly advantageous. The flow through the catalyst modules with exhaust gas is not affected by the support grid. The sealing elements prevent exhaust gas from flowing through the catalyst bodies. The individual tolerance compensation allows the particularly advantageous integration of the catalyst unit in a housing structure of an exhaust gas catalyst. According to a further advantageous embodiment, the counter-holder has a plurality of mutually parallel counter-holder struts, the counter-holder struts of the counter-holder engage at a first end to a housing structure of a catalytic converter and cooperate at opposite second ends with a perpendicular to the counter struts extending hold-down strut, via the hold-down strut to clamp the catalyst modules between the support grid and the counter-holder on all counter struts a force can be applied. Preferably, a clamping force for clamping the catalyst modules between the support grid and the counter-holder via Niederdrücker can be applied, which attack on the one hand on the hold-down strut and on the other hand on the housing structure of the catalytic converter. This development of the catalyst unit is particularly preferred. The counter struts, which cooperate with the hold-down strut, allow easy clamping of the catalyst modules between the support grid and the counter-holder. About the depressor, the clamping force for clamping the catalyst modules can be applied particularly advantageous to the hold-down strut and on the hold-down strut on the counter struts.

According to a further advantageous refinement, spring elements elastically support the support grid on a housing structure of the exhaust gas catalytic converter and / or the holddown strut on the housing structure of the exhaust gas catalytic converter and / or the counter support struts on the catalyst modules. This elastic support is to compensate for temperature-related expansions of advantage.

The exhaust gas catalyst according to the invention is defined in claim 13.

Preferred embodiments of the invention will become apparent from the dependent claims and the description below. Embodiments of the invention will be described, without being limited thereto, with reference to the drawings. Showing: 1 shows a perspective view of a catalytic converter unit according to the invention for an exhaust gas catalytic converter;

FIG. 2 shows the catalyst unit of FIG. 1 without a depressor; FIG.

FIG. 3 shows the arrangement of FIG. 2 without hold-down strut; FIG. FIG. 4 shows the arrangement of FIG. 3 without counter struts with partially removed catalyst modules; FIG.

FIG. 5 shows the arrangement of FIG. 4 with a single catalyst module; FIG.

Fig. 6: a support grid of the catalyst unit of Fig. 1;

FIG. 7: counter support struts of the catalyst unit of FIG. 1; FIG. Fig. 8: the detail XIII of Fig. 1; and

9: the detail IX of FIG. 1.

The invention relates to a catalyst unit for an exhaust gas catalytic converter of an internal combustion engine for marine applications and an exhaust gas catalytic converter. In particular, the catalyst unit according to the invention is designed as an SCR catalyst unit for an SCR catalytic converter of a marine diesel engine. Figs. 1 to 9 show different views and details of a preferred embodiment of a catalyst unit.

The catalyst unit 10 according to the invention has a plurality of catalyst modules 1 1, wherein the catalyst modules 1 1 are positioned like an array in the form of columns and rows directly next to each other. Each catalyst module 1 1 has a metallic housing 12, which accommodates a ceramic catalyst body, not shown. In the embodiment shown, the metallic casings 12 have a rectangular cross-section, wherein these casings 12 surround a rectangular catalyst body in sections on the outside. The housing 12, which is also referred to as Canning, releases the catalyst body at opposite ends, forming an inflow end and an outflow end of the respective catalyst module 11. The catalyst unit 10 has a support grid 13. The catalyst modules 1 1 are in the region of first through-flow ends on the support grid 13. At opposite second through-flow ends of the catalyst modules 1 1, a counter-holder 14 is positioned, wherein the catalyst modules 1 1 are clamped between the support grid 13 and the counter-holder 14.

As best seen in Fig. 6, the support grid 13 a plurality of mutually parallel first support struts 15a and a plurality of parallel to each other and perpendicular to the first support struts 15a extending second support struts 15b, on which the catalyst modules 1 1 are positioned. Between immediately parallel to each other support struts 15a and 15b of the support grid 13, on which immediately adjacent catalyst modules 1 1 is positioned, a respective sealing element 1 6 (see FIG. 9) arranged, which an exhaust gas flow between the housings 12 immediately adjacent catalyst modules 1 1 prevented. Thus, in Fig. 9, a gap

17 between the housings 12 of two directly adjacent catalyst modules 1 1 shown, wherein the sealing element 1 6 prevents exhaust gas flow through this gap 17 therethrough and therefore ensures that all exhaust flow through the catalyst body of the catalyst modules 1 1 flows. This in

Fig. 9 visible sealing element 1 6 is profiled on a U-shaped profile carrier

18 is positioned, which is positioned in Fig. 9 between immediately parallel to each other support struts 15b of the support grid 13.

As can be seen in FIG. 9, the housings 12 of the catalyst modules 1 1 have curved or flanged bearing feet 19 at their first through-flow ends, which support themselves on a sealing element 16 or stand on the same. To increase the footprint, thicker material may be used at the ends of the housing than at the remainder of the housing, instead of a cladding. An advantage here is a width of 2mm - 20mm at the

Front sides of the housing. Between the support struts 15a, 15b and the first through-flow ends of the catalyst modules 11, a gap 20 is formed in FIG. 9. det, but preferably after the jamming of the catalyst modules 1 1 between the support grid 13 and the anvil 14 disappears.

As can be seen from FIG. 9, individual support struts 15a, 15b of the support grid 13 cooperate with each catalyst module 11. In the free spaces defined between directly adjacent support struts 15a and 15b, in which the sealing elements 16 are positioned, the catalyst modules 11 engage with their support feet 19. In this way, the mutually parallel support struts 15a, 15b provide individual tolerance compensation for dimensional tolerances of the catalyst modules 11, so that the individual tolerances of adjacent catalyst modules 11 do not add up. As a result, the catalyst unit 10 according to the invention can be integrated particularly advantageously into a housing structure of an exhaust gas reactor.

As already stated, the catalyst modules 1 1 are clamped between the support grid 13 and the counter-holder 14. The counter-holder 14 has a plurality of mutually parallel counter-holder struts 21. Each of the counter struts 21 engages with a first end 22 on a housing structure of the catalytic converter, at an opposite second end 23 cooperates with the counter struts 21 a perpendicular to the same extending hold-down strut 24 together. About the hold-down brace 24 is for clamping the catalyst modules 1 1 between the support grid 13 and the anvil 14 on the Gegenhalterstreben 21 a clamping force applied. By means of this clamping force, the counter support struts 23 are pressed against the housing 12 of the catalyst modules 1 1 and thus ultimately the catalyst modules 1 1 against the support grid 13, whereby the clamping of the catalyst modules 1 1 takes place between support grid 13 and counter holder 14.

As can best be seen in FIG. 8, counter support struts 21, which extend along two rows or columns of catalyst modules 1 1 positioned immediately next to each other, are supported on the catalyst modules 11 from these immediately adjacent rows or columns. Only the outer counter struts 21 are based only on the catalyst modules 1 1 of a single row or column.

As best seen in FIG. 8, the hold-down strut 24 has recesses 25 into which the counter-holding struts 21 engage in the region of their second ends 23.

The clamping force which is to be applied via the hold-down bar 24 to the counter-holder struts 21 of the counter-holder 14 is provided by means of two press-downs 26 which engage at opposite ends of the hold-down bar 24. As best seen in FIG. 8, the respective depressor 26 engages with one end on the hold-down strut 24 and with a second end on a housing structure 27 of a Katalysatorge- housing, via the co-operating with the depressor 26 nuts 28, the distance between the housing structure 27 and the hold-down strut 24 and thus the clamping force can be adjusted. In the embodiment shown, therefore, the clamping force on the hold-down strut 24 and the counter struts 21 is applied to the housing 12 of the catalyst modules 1 1, wherein the clamping force is provided via two depressors 26 which engage at opposite ends of the hold-down strut 24.

According to an advantageous embodiment of the invention, the catalyst unit 10 via elastic spring elements, not shown, which act between the support grid 13 and a housing structure of a catalyst housing of a catalytic converter to store elastically or to support this housing structure. Likewise, the counter-holder 14 can be elastically supported on the housing structure, namely via spring elements, not shown, which are supported between the hold-down strut 24 and the housing structure 27. Furthermore, it is possible that spring elements, not shown, are provided, which elastically support the counterholder struts 21 with respect to the housings 12 of the catalyst modules 11. Zen. By means of these spring elements, changes in the geometry of the catalyst unit 10 caused by temperature cycles can be compensated.

In addition, it is possible to mount spring elements between the counterholder struts 21 and the holddown strut 24 so that the tolerances of each counter strut 21 and of the housing 12 located therebelow can be intercepted. Furthermore, it is possible to flexibly perform the counter struts, for example in spring steel.

The catalyst unit 10 according to the invention accordingly comprises a plurality of catalyst modules 11 which are arranged in an array-like manner in columns and rows positioned directly next to each other. The catalyst modules 1 1 are supported with their rectangular in cross-section housings 12 via first ends on a static support grid 13 from. On the opposite side of the catalyst modules 1 1, a counter-holder 14 is arranged, which comprises a plurality of movable counter support struts 21 and a hold-down strut 24. The catalyst modules 1 1 are clamped between the static support grid 13 and the movable counter-holder 14.

In the region of the supporting grid 14, the housings 12 of the catalyst modules 11 are supported on mutually parallel support struts 15a, 15b, sealing elements 16 being positioned between directly adjacent support struts.

Each two adjacent rows or columns of catalyst modules 1 1 is preferably a common counter-holder strut 21 is used, which rests on edges of the housing 12 of the catalyst modules 1 1 adjacent in the immediately adjacent rows or columns. An exception to this is the outermost rows of catalysers or columns, in which the corresponding counter-holder strut 21 rests on the housings of the catalyst modules 11 of a single row or column of catalyst modules 11. Each counter strut 21 is connected at one end 22 fixed to a housing structure of a housing of the catalytic converter, at the opposite second end 23 of the counter struts 21 attacks the common hold-down strut 24 to finally clamp the catalyst modules 1 1 between the support grid 13 and the anvil 14. The clamping force can be applied to the hold-down strut 24 via depressors 26.

Thermal expansions of the catalyst unit 10 are preferably compensated by spring elements, not shown, which act on the support grid 13 and / or on the hold-down strut 24 and / or on the counter struts 21.

An alternative to providing a compensation of thermal expansion is to manufacture the counter struts 21 and preferably the hold-down strut 24 of the counter-holder 14 of an elastic material, in particular of spring steel. As a result, possibly occurring thermal expansion can be directly absorbed and compensated by the counter-holder 14.

Several such catalytic converter units 10 can be used in a housing of an exhaust gas catalytic converter.

As best seen in FIGS. 5 and 6, parallel to the support struts 15b of the support grid 13 are struts 29 which serve to allow the support grid 13 to be safely entered by persons. These struts 29 do not hinder the flow through the catalyst modules 1 1 with exhaust gas. LIST OF REFERENCE NUMBERS

10 catalyst unit

1 1 catalyst module

12 housing

13 support grid

14 counterholds

15a support strut

15b support strut

16 sealing element

17 gap

18 profile beam

19 support foot

20 gap

21 counter strut

22 end

23 end

24 hold-down bar

25 recess

26 depressors

27 housing structure

28 mother

29 strut

Claims

claims

Catalyst unit (10) for an exhaust gas catalytic converter, in particular SCR catalytic converter unit for an SCR exhaust gas catalytic converter of an internal combustion engine, with a plurality of catalyst modules (1 1), each catalytic converter module (11) comprising a ceramic catalyst body through which exhaust gas flows, and a metallic housing (12) for the ceramic catalyst body, wherein the respective ceramic catalyst body in the respective metallic housing (12) is received and surrounded by the same sections, characterized in that the catalyst modules (1 1) are positioned with first through-flow ends on a support grid (13), and that at the opposite second through-flow ends of the catalyst modules (1 1), a counter-holder (14) is positioned, wherein the catalyst modules (1 1) between the support grid (13) and the counter-holder (14) are clamped.

2. Catalyst unit according to claim 1, characterized in that the

Support grid (13) has a plurality of mutually parallel first support struts (15a) and a plurality of also parallel to each other and perpendicular to the first support struts (15a) extending second support struts (15b) on which the catalyst modules (1 1) are positioned.

3. Catalyst unit according to claim 2, characterized in that between directly parallel support struts (15a, 15b) of the support grid (13) on which immediately adjacent catalyst modules (1 1) are positioned, a sealing element (1 6) is positioned, which prevents an exhaust gas flow between the housings (12) of the adjacent catalyst modules (1 1).

4. Catalyst unit according to claim 3, characterized in that the

Sealing elements (1 6) on between directly parallel to each other support struts (15a, 15b) positioned profile carriers (18) are positioned.

5. Catalyst unit according to claim 3 or 4, characterized in that directly parallel to each other support struts (15a, 15b) for the respective immediately adjacent catalyst modules (1 1) provide an individual tolerance compensation for the catalyst modules (1 1).

6. Catalyst unit according to one of claims 1 to 5, characterized in that spring elements elastically support the support grid on a housing structure of the catalytic converter.

7. Catalyst unit according to one of claims 1 to 6, characterized in that the counter-holder (14) has a plurality of mutually parallel counter support struts (21).

8. catalyst unit according to claim 7, characterized in that the counter struts (21) of the counter-holder (20) at a first end (22) on a housing structure of a catalytic converter attack and at opposite second ends (23) with a perpendicular to the Counterhold struts (21) extending hold-down bar (24) cooperate, wherein on the hold-down bar (24) for clamping the catalyst modules (1 1) between the support grid (13) and the anvil (14) on a plurality of counter support struts (21) a force can be applied.

Catalyst unit according to claim 7 or 8, characterized in that the counter support struts (21), which extend along immediately adjacent catalyst modules (1 1), each jamming the immediately adjacent catalyst modules (1 1) with the support grid (13).

Catalyst unit according to claim 8 or 9, characterized in that a clamping force for clamping the catalyst modules (1 1) between the support grid (13) and the counter-holder (14) via Niederdrücker (26) can be applied, on the one hand to the hold-down strut (24 and the other on the housing structure (27) of the catalytic converter attack.

1 1. Catalyst unit according to one of claims 8 to 10, characterized in that the spring elements elastically support the hold-down strut (24) on a housing structure (27) of the catalytic converter.

12. Catalyst unit according to one of claims 7 to 1 1, characterized in that spring elements support the counter support struts (21) on the catalyst modules (1 1) or on the hold-down strut (24) elastically.

13. Catalyst unit according to one of claims 7 to 12, characterized in that the counter support struts (21) made of elastic material, preferably spring steel, are made

14. catalytic converter, with a plurality of catalyst units (10) according to any one of claims 1 to 13.