U.S. patent application number 14/115207 was filed with the patent office on 2015-04-30 for exhaust system for a diesel engine.
This patent application is currently assigned to DAF TRUCKS N.V.. The applicant listed for this patent is Albertus Martinus Herman Wieland. Invention is credited to Albertus Martinus Herman Wieland.
Application Number | 20150113965 14/115207 |
Document ID | / |
Family ID | 46246154 |
Filed Date | 2015-04-30 |
United States Patent
Application |
20150113965 |
Kind Code |
A1 |
Wieland; Albertus Martinus
Herman |
April 30, 2015 |
EXHAUST SYSTEM FOR A DIESEL ENGINE
Abstract
An exhaust gas system for a diesel engine comprises a filter 9
that includes channels extending in the direction of flow and
having porous walls 13 which are clad with an SCR catalyst coating
25. Neighbouring channels are alternately shut off by end plugs 15,
17 at the inlet end and the outlet end, as a result of which the
exhaust gas is forced to flow through the walls. The walls 13 are
coated with an AMOX catalyst coating 29 from the end 21 over a
distance 27. The end plugs 17 in the outlet ends have a length that
at least equals said distance 27. As a result, one side of the wall
sections coated with the AMOX catalyst coating is covered and the
exhaust gas cannot but flow first through the wall sections coated
with SCR catalyst coating 25 and only then can the exhaust gas flow
past the wall sections coated with the AMOX catalyst coating
29.
Inventors: |
Wieland; Albertus Martinus
Herman; (Schaijk, NL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Wieland; Albertus Martinus Herman |
Schaijk |
|
NL |
|
|
Assignee: |
DAF TRUCKS N.V.
Eindhoven
NL
|
Family ID: |
46246154 |
Appl. No.: |
14/115207 |
Filed: |
May 1, 2012 |
PCT Filed: |
May 1, 2012 |
PCT NO: |
PCT/NL2012/050304 |
371 Date: |
June 27, 2014 |
Current U.S.
Class: |
60/297 |
Current CPC
Class: |
Y02T 10/12 20130101;
F01N 3/2066 20130101; F01N 2510/06 20130101; F01N 2250/02 20130101;
Y02T 10/24 20130101; F01N 3/0222 20130101; F01N 3/035 20130101;
F01N 2570/18 20130101; F01N 2510/0682 20130101 |
Class at
Publication: |
60/297 |
International
Class: |
F01N 3/035 20060101
F01N003/035 |
Foreign Application Data
Date |
Code |
Application Number |
May 2, 2011 |
NL |
2006705 |
Jun 24, 2011 |
NL |
2006993 |
Claims
1. An exhaust gas system for a diesel engine comprising an inlet
and an outlet and a filter located in between comprising a
plurality of channels arranged next to one another and having
porous walls, where neighbouring channels are alternately shut off
by an end plug at the inlet end and the outlet end, as a result of
which the exhaust gas is forced to flow through the walls which are
at least partially coated with a first coating, characterized in
that from the outlet end to a distance from this outlet end, the
walls are coated with a second coating, where the end plugs in the
outlet ends have a length that is at least equal to said distance
over which the walls are coated with the second coating.
2. An exhaust gas system as claimed in claim 1, characterized in
that the filter is a diesel particle filter, in that the first
coating is a selective catalytic reduction coating and in that the
second coating is an ammonia oxidation catalyst coating.
Description
FIELD OF THE INVENTION
[0001] The invention relates to an exhaust gas system for a diesel
engine comprising an inlet and an outlet and a filter located in
between comprising a plurality of channels arranged next to one
another and having porous walls, where neighbouring channels are
alternately shut off by an end plug at the inlet end and the outlet
end, as a result of which the exhaust gas is forced to flow through
the walls which are at least partially coated with a first
coating.
STATE OF THE ART
[0002] An exhaust system of this type is generally known in the
form of a diesel particle filter (DPF) in which the walls of the
channels are coated with a selective catalytic reduction catalyst
(SCR catalyst). The end plugs are generally installed before the
walls are coated.
[0003] Once the exhaust gas has flown through the DFP with the SCR
catalyst on it, it is desirable to have the filtered exhaust gas
flow past an ammonia oxidation catalyst (AMOX catalyst).
SUMMARY OF THE INVENTION
[0004] It is an object of the invention to provide an exhaust gas
system of the type defined in the opening paragraph which is
advantageously provided with an AMOX catalyst. For this purpose the
exhaust gas system according to the invention is characterized in
that from the outlet end to a distance from this outlet end, the
walls are coated with a second coating, where the end plugs in the
outlet ends have a length that is at least equal to said distance
over which the walls are coated with the second coating. If the
AMOX catalyst has not been coated in the place of the end plugs on
the walls of the channels, the exhaust gas will partially flow
through the AMOX catalyst coated wall sections and partially
through the SCR catalyst coated wall sections. By covering one side
of the sections of the walls which are coated with the AMOX
catalyst, the exhaust gas cannot but flow first through the SCR
catalyst coated sections of the walls. Not until then can the
exhaust gas flow past the wall sections coated with the AMOX
catalyst coating. By shutting off the wall sections coated with the
AMOX catalyst coating by means of the end plugs, no extra closing
means are required. Only the end plugs in the outlet end need to be
made longer than normal.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0005] The invention will be further described below in more detail
with reference to an embodiment of the exhaust gas system according
to the invention represented in the drawing figures, in which:
[0006] FIG. 1 shows an embodiment of the exhaust gas system
according to the invention in longitudinal section; and
[0007] FIG. 2 gives a detailed representation of the interior of
the exhaust gas system shown in FIG. 1.
DETAILED DESCRIPTION OF THE DRAWING FIGURES
[0008] FIG. 1 shows an embodiment of the exhaust gas system for a
diesel engine according to the invention. The exhaust gas system 1
comprises a housing 3 which has an inlet 5 and an outlet 7 and a
filter 9 accommodated in the housing. The filter comprises channels
11A and 11B extending in the direction of flow and having porous
walls 13. The channels are open at one end and closed at the other
by means of an end plug 15, 17. The channels 11A open at the inlet
end 19 and closed at the outlet end 21 are then surrounded by
channels 19B open at the outlet end 21 and closed at the inlet end
19. As a result, the exhaust gas 19 is forced to flow through the
walls 13.
[0009] FIG. 2 gives a detailed representation of the interior of
the filter 9 in enlarged form. From the inlet end 19 onwards the
walls 13 are coated with an SCR coating 25 over a first distance
and coated with an AMOX catalyst coating 29 from the outlet end 21
onwards over a second distance 27. The end plugs 17 in the outlet
ends have a length that at least equals said second distance 27
over which the walls are coated with the AMOX catalyst coating 29.
As a result, one side of the wall sections coated with the AMOX
catalyst coating is covered and the exhaust gas cannot but flow
first through the wall sections 13 coated with SCR catalyst coating
25. Only then can the exhaust gas flow past the wall sections 13
coated with the AMOX catalyst coating 29.
[0010] Albeit the invention has been elucidated in the foregoing
with reference to the drawing figures, it should be set out that
the invention is not by any manner or means restricted to the
embodiments shown in the drawing figures. The invention also
extends to any embodiments deviating from the embodiments shown in
the drawing figures within the spirit and scope defined by the
claims.
* * * * *