U.S. patent application number 13/387935 was filed with the patent office on 2012-07-26 for method for controlling injection amount of fuel of burner and aftertreating device of exhaust gas.
This patent application is currently assigned to SK INNOVATION CO., LTD.. Invention is credited to Hongseok Jung, Sunghwan Kim, Yongwoo Kim, Youngshol Kim, Yunsik Kim, Myeong Soo Seo, Kunchong You.
Application Number | 20120186232 13/387935 |
Document ID | / |
Family ID | 43529895 |
Filed Date | 2012-07-26 |
United States Patent
Application |
20120186232 |
Kind Code |
A1 |
Kim; Youngshol ; et
al. |
July 26, 2012 |
Method for Controlling Injection Amount of Fuel of Burner and
Aftertreating Device of Exhaust Gas
Abstract
Disclosed is a method for controlling an injection amount of
fuel of a burner and an aftertreating device of exhaust gas, and
more particularly, to a method for controlling an injection amount
of fuel of a burner and an aftertreating device of exhaust gas, in
which the burner is controlled in consideration of exothermic
effect due to a catalytic filter, thereby stably reducing exhaust
gas.
Inventors: |
Kim; Youngshol; (Daejeon,
KR) ; Kim; Yongwoo; (Daejeon, KR) ; You;
Kunchong; (Seoul, KR) ; Seo; Myeong Soo;
(Seoul, KR) ; Kim; Sunghwan; (Daejeon, KR)
; Jung; Hongseok; (Daejeon, KR) ; Kim; Yunsik;
(Chungcheongnam-do, KR) |
Assignee: |
SK INNOVATION CO., LTD.
Seoul
KR
|
Family ID: |
43529895 |
Appl. No.: |
13/387935 |
Filed: |
July 30, 2010 |
PCT Filed: |
July 30, 2010 |
PCT NO: |
PCT/KR2010/005030 |
371 Date: |
April 16, 2012 |
Current U.S.
Class: |
60/274 ;
60/311 |
Current CPC
Class: |
F01N 3/2033 20130101;
F01N 9/00 20130101; Y02T 10/40 20130101; Y02T 10/26 20130101; F01N
3/0253 20130101; Y02T 10/12 20130101; Y02T 10/47 20130101 |
Class at
Publication: |
60/274 ;
60/311 |
International
Class: |
F01N 3/025 20060101
F01N003/025 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 30, 2009 |
KR |
10-2009-0069951 |
Claims
1. An aftertreating device of exhaust gas, comprising: a burner
disposed at a vent pipe in which the exhaust gas generated from a
diesel engine is flowed and having a fuel injecting part and an
igniting means for increasing temperature of the exhaust gas; a
diesel particulate filter (DPF) which is disposed at a rear side of
the burner in a flow direction of the exhaust gas so as to burn
organic materials or particulate matters (PM) contained in the
exhaust gas; a temperature sensor for measuring the temperature of
the exhaust gas; and a controlling part which controls a fuel
injection amount of the fuel injecting part using an engine
displacement estimated through the temperature measured from the
temperature sensor.
2. The aftertreating device of claim 1, wherein the controlling
part estimates the engine displacement by further using RPM
information of the diesel engine.
3. The aftertreating device of claim 1, wherein the temperature
sensor is disposed at a rear side of the DPF in the flow direction
of the exhaust gas.
4. The aftertreating device of claim 1, further comprising a
pro-catalyst disposed between the burner and the DPF, wherein the
temperature sensor is disposed between the pro-catalyst and the DPF
or at a rear side of the DPF in the flow direction of the exhaust
gas.
5. A method for controlling an injection amount of fuel of a burner
in the aftertreating device of claim 1.
6. The method of claim 5, wherein the controlling part controls the
fuel injection amount so that an amount of hydrocarbon compound is
1.about.3000 ppm at the rear side of the burner in the flow
direction of the exhaust gas.
7. The method of claim 6, wherein the controlling part controls the
fuel injection amount to be 0.001.about.0.02 g for 1 minute per 1 l
of an exhaust emission rate calculated by an equation 1 as follows:
[Equation 1] Exhaust emission rate (E)=aengine displacementRPM (a=a
constant of a load factor).
8. A method for controlling an injection amount of fuel of a burner
in the aftertreating device of claim 2.
9. A method for controlling an injection amount of fuel of a burner
in the aftertreating device of claim 3.
10. A method for controlling an injection amount of fuel of a
burner in the aftertreating device of claim 4.
11. The method of claim 8, wherein the controlling part controls
the fuel injection amount so that an amount of hydrocarbon compound
is 1.about.3000 ppm at the rear side of the burner in the flow
direction of the exhaust gas.
12. The method of claim 9, wherein the controlling part controls
the fuel injection amount so that an amount of hydrocarbon compound
is 1.about.3000 ppm at the rear side of the burner in the flow
direction of the exhaust gas.
13. The method of claim 10, wherein the controlling part controls
the fuel injection amount so that an amount of hydrocarbon compound
is 1.about.3000 ppm at the rear side of the burner in the flow
direction of the exhaust gas.
14. The method of claim 11, wherein the controlling part controls
the fuel injection amount to be 0.001.about.0.02 g for 1 minute per
1 l of an exhaust emission rate calculated by an equation 1 as
follows: [Equation 1] Exhaust emission rate (E)=aengine
displacementRPM (a=a constant of a load factor).
15. The method of claim 12, wherein the controlling part controls
the fuel injection amount to be 0.001.about.0.02 g for 1 minute per
1 l of an exhaust emission rate calculated by an equation 1 as
follows: [Equation 1] Exhaust emission rate (E)=aengine
displacementRPM (a=a constant of a load factor).
16. The method of claim 13, wherein the controlling part controls
the fuel injection amount to be 0.001.about.0.02 g for 1 minute per
1 l of an exhaust emission rate calculated by an equation 1 as
follows: [Equation 1] Exhaust emission rate (E)=aengine
displacementRPM (a=a constant of a load factor).
Description
TECHNICAL FIELD
[0001] The present invention relates to a method for controlling an
injection amount of fuel of a burner and an aftertreating device of
exhaust gas, and more particularly, to a method for controlling an
injection amount of fuel of a burner and an aftertreating device of
exhaust gas, in which the burner is controlled in consideration of
exothermic effect due to a catalytic filter, thereby stably
reducing exhaust gas.
BACKGROUND ART
[0002] In general, since a diesel engine has higher power and lower
fuel expenses than a gasoline engine, it is widely applied to
vehicles, construction equipments, ships and the like.
[0003] However, the diesel engine is a four-stroke engine in which
fuel is injected into the engine and then burnt in a compression
ignition method, and in a self-ignition process of the fuel,
incomplete combustion occurs due to non-uniformity of a fuel-air
ratio, and thus noxious particle (exhaust gas) is generated.
[0004] Particularly, the noxious particle mainly contains NO.sub.x,
particulate matter (PM) and CO, and there is a report that the
noxious particle accounts for 40% of the total air pollution.
Therefore, exhaust emissions are regulated in many countries, and
in order to satisfy the regulation, there has been disclosed an
aftertreating device of the exhaust gas, which is inserted into a
vent pipe so as to reduce the exhaust gas.
[0005] In most of the aftertreating device, the exhaust gas
generated in a diesel engine is introduced into a filter having a
catalyst and then burnt in the filter, thereby reducing the
emissions of exhaust gas.
[0006] However, owing to low temperature of the exhaust gas when
the exhaust gas is simply introduced into the filter, there has
been also developed a new technique in which temperature of the
exhaust gas is increased before being introduced into the filter,
thereby increasing the combustion rate.
[0007] In order to increase the temperature of the exhaust gas,
there have been proposed a fuel injection aftertreating device and
an aftertreating device using a burner.
[0008] In the fuel injection aftertreating device, injected fuel is
oxidized while being passed through a catalytic filter and/or pro
catalyst, and thus temperature of the filter in which soot is
collected through such reaction is increased.
[0009] However, in the fuel injection aftertreating device, since
the temperature of the exhaust gas is increased using exothermic
reaction occurred through the catalytic oxidation of fuel, it takes
long time to obtain a target temperature value. In case that the
fuel is excessively injected, non-reacted fuel is exhausted and
thus environmental pollution occurs. Further, a temperature of
180.degree. C. or more is typically needed to effectively achieve
the catalytic oxidation, but if a vehicle is driven with the
exhaust gas having a lower temperature than 180.degree. C., the
catalytic oxidation is not smoothly achieved. Particularly, in case
that the non-reacted fuel is exhausted, milk-white smoke is
discharged and may cause a serious safety problem in driving and
also make an ill appearance.
[0010] In the aftertreating device using a burner, the burner is
disposed between an engine and a catalytic filter so as to directly
heat the exhaust gas, and the burner is operated in an engine off
or idling state or an engine driving state.
[0011] In case of a method for removing the soot by operating the
burner in the engine off or idling state, it is possible to stably
drive the engine since the burner is operated under the same
condition. However, since the burner is operated only in a state
that the catalytic filter is saturated with the collected soot, it
is inconvenient to intentionally stop the engine in order to
operate the burner.
[0012] In case of a method for removing the soot by operating the
burner in the engine driving state, it is necessary to measure a
temperature of the exhaust gas introduced into the burner and a
temperature at a rear end of the burner in order to decide a fuel
injection amount supplied to the burner. If a pro-catalyst is
provided at a front end of the catalytic filter, it is necessary to
measure a temperature of the exhaust gas introduced into the
pro-catalyst in order to decide a fuel injection amount supplied to
the burner.
[0013] However, in case that the engine is applied to a vehicle, a
temperature and an amount of the exhaust gas are rapidly changed
while the vehicle is driven. Therefore, the fuel injected into the
aftertreating device using the burner may be erroneously calculated
comparing with an actually necessary amount.
[0014] When the fuel injection amount is decided using the
temperature measured at a front end of the catalytic filter in case
of using only the catalytic filter or the temperature measured at a
front end of the pro-catalyst in case of using both of the
pro-catalyst and the filter, it is impossible to reflect the
heating effect due to heat generated while the fuel supplied to the
burner is oxidized through the catalytic filter and/or pro
catalyst.
[0015] In other words, if a set temperature value of the
aftertreating device using the burner is 500.degree. C., the set
temperature at the rear end of the burner (the front end of the
catalytic filter) is maintained within a predetermined error range.
But the temperature of the exhaust gas after passing through the
catalytic filter or the pro-catalyst may be 900.degree. C. between
the catalytic filter and the pro-catalyst or at the rear end of the
catalytic filter, because an excessive and non-reacted hydrocarbon
compound generates the heat by catalytic combustion while passing
through the catalyst.
[0016] If the temperature is excessively increased as described
above, durability of the filter is deteriorated, and in the worst
case, the filter may be damaged.
DISCLOSURE OF INVENTION
Technical Problem
[0017] An object of the present invention is to provide an
aftertreating device of exhaust gas, which controls a burner in
consideration of exothermic effect occurred when fuel injected from
the burner passes through a catalytic filter or a pro-catalyst,
thereby stably heating the exhaust gas and also efficiently
reducing the emissions of exhaust gas.
[0018] Another object of the present invention is to provide an
aftertreating device of exhaust gas, which properly maintains an
internal temperature of the aftertreating device of exhaust gas and
thus minimizes deterioration in the durability, and also which
appropriately operates the burner according to a vehicle condition
and a driving state.
Solution to Problem
[0019] To achieve the object of the present invention, the present
invention provides a aftertreating device of exhaust gas, including
a burner 30 disposed at a vent pipe 20 in which the exhaust gas
generated from a diesel engine 10 is flowed and having a fuel
injecting part 31 and an igniting means 32 for increasing
temperature of the exhaust gas; a diesel particulate filter (DPF)
40 which is disposed at a rear side of the burner 30 in a flow
direction of the exhaust gas so as to burn organic materials or
particulate matters (PM) contained in the exhaust gas; a
temperature sensor 70 for measuring the temperature of the exhaust
gas; and a controlling part 50 which controls a fuel injection
amount of the fuel injecting part 31 using an engine displacement
estimated through the temperature measured from the temperature
sensor 70.
[0020] Preferably, the controlling part 50 estimates the engine
displacement by further using
[0021] RPM information of the diesel engine 10, and the temperature
sensor 70 is disposed at a rear side of the DPF 40 in the flow
direction of the exhaust gas.
[0022] Preferably, the aftertreating device 100 of exhaust gas
further includes a pro-catalyst 60 disposed between the burner 30
and the DPF 40, wherein the temperature sensor 70 is disposed
between the pro-catalyst 60 and the DPF 40 or at a rear side of the
DPF 40 in the flow direction of the exhaust gas.
[0023] Further, the present invention provides a method for
controlling an injection amount of fuel of a burner using the
aftertreating device of exhaust gas as described above.
[0024] Preferably, the controlling part 50 controls the fuel
injection amount so that an amount of hydrocarbon compound is
1.about.3000 ppm at the rear side of the burner 30 in the flow
direction of the exhaust gas.
[0025] Preferably, the controlling part 50 controls the fuel
injection amount to be 0.001.about.0.02 g for 1 minute per 1 l of
an exhaust emission rate calculated by an equation 1 as
follows:
[Equation 1]
Exhaust emission rate (E)=aengine displacementRPM
[0026] (a=a constant of a load factor).
Advantageous Effects of Invention
[0027] According to the method for controlling the injection amount
of fuel of the burner and the aftertreating device of exhaust gas
according to the present invention as described above, there is
provided a sensor for controlling the fuel injection amount of the
burner in consideration of the exothermic effect occurred when the
fuel injected from the burner passes through the catalytic filter
or the pro-catalyst, thereby efficiently reducing the emissions of
exhaust gas without deterioration in the durability.
[0028] Further, the present invention appropriately operates the
burner according to a vehicle condition and a driving state and
prevents the problems occurred by the non-reacted fuel injected
from the burner.
BRIEF DESCRIPTION OF DRAWINGS
[0029] The above and other objects, features and advantages of the
present invention will become apparent from the following
description of preferred embodiments given in conjunction with the
accompanying drawings, in which:
[0030] FIGS. 1 and 2 are views of an aftertreating device of
exhaust gas in accordance with each embodiment of the present
invention.
[0031] FIG. 3 is a graph of temperature changed by controlling a
fuel injection amount in the aftertreating device of exhaust gas in
accordance with the present invention.
[0032] FIG. 4 is a graph showing a change in temperature in a
comparative example.
DETAILED DESCRIPTION OF MAIN ELEMENTS
[0033] 10: engine [0034] 20: vent pipe [0035] 30: burner [0036] 31:
fuel injecting part [0037] 32: igniting means [0038] 40: catalytic
filter [0039] 50: controlling part [0040] 60: pro-catalyst [0041]
100: aftertreating device of exhaust gas
BEST MODE FOR CARRYING OUT THE INVENTION
[0042] Hereinafter, the embodiments of the present invention will
be described in detail with reference to accompanying drawings.
[0043] FIGS. 1 and 2 are views of an aftertreating device 100 of
exhaust gas in accordance with each embodiment of the present
invention.
[0044] The aftertreating device 100 of exhaust gas of the present
invention includes a burner 30 which is disposed at a vent pipe 20,
a catalytic filter 40, a temperature sensor 70 and a controlling
part 50.
[0045] The aftertreating device 100 of exhaust gas of the present
invention is disposed at the vent pipe 20 through which the exhaust
gas generated from a diesel engine 10 is flowed.
[0046] The burner 30 includes a fuel injecting part 31 and an
igniting means 32 so as to heat the exhaust gas. The drawing shows
an example that the burner 30 is disposed to be perpendicular to
the vent pipe 20. The burner 30 may be disposed to be parallel with
the flow of the exhaust gas or otherwise.
[0047] The catalytic filter 40 is provided at a rear side of the
burner 30 in a flow direction of the exhaust gas so as to burn
organic material or particulate matter (PM). The catalytic filter
40 functions to burn the exhaust gas heated by the burner 30 and
thus reduce noxious material of the exhaust gas.
[0048] The controlling part 50 is a means for controlling a fuel
injection amount of the fuel injecting part 31 using an engine
displacement estimated through a temperature measured from a
temperature sensor 70. The controlling part 50 controls the whole
operation of the aftertreating device 100 of exhaust gas of the
present invention.
[0049] The aftertreating device 100 of exhaust gas of the present
invention is a main element for controlling the fuel injection
amount of the controlling part 50, uses the temperature measured by
the temperature sensor 70, and may estimate the engine displacement
by further using RPM information of the diesel engine 10.
[0050] In case that the burner 30 and the catalytic filter 40 are
provided, in turn, at the vent pipe 20 in the flow direction of the
exhaust gas, as shown in FIG. 1, the temperature sensor 70 is
provided at a rear side of the catalytic filter 40, and the
controlling part 50 analyzes the temperature information measured
from the temperature sensor 70, whereby the fuel injection amount
of the burner 30 is controlled in consideration of the increase of
the temperature due to exothermic effect of the catalytic
filter.
[0051] Meanwhile, the aftertreating device 100 of exhaust gas of
the present invention may further include a pro-catalyst 60 between
the burner 30 and the catalytic filter 40. The pro-catalyst 60
functions to burn the organic material contained in the exhaust gas
and increase the temperature of the exhaust gas. For example, a
diesel oxidation catalyst (DOC) may be used as the pro-catalyst
60.
[0052] Herein, the temperature sensor 70 may be disposed between
the pro-catalyst 60 and the catalytic filter 40 in the flow
direction of the exhaust gas, as shown in FIG. 2, or disposed at
the rear side of the catalytic filter 40 as shown in FIG. 1, or
disposed between the pro-catalyst 60 and the catalytic filter 40
and also at the rear side of the catalytic filter 40.
[0053] By controlling the fuel injection amount of the burner 30
using the temperature sensor 70, the aftertreating device 100 of
exhaust gas of the present invention prevents excessive increase of
the temperature at a certain place and thus stably reduces the
noxious material and improves the durability.
[0054] In the aftertreating device 100 of exhaust gas of the
present invention, it is possible to prevent the fuel from being
excessively supplied by properly controlling the fuel injection
amount of the burner 30, and also to enhance the durability.
[0055] The controlling part 50 compares the temperature measured
from the temperature sensor 70 and controls the fuel injection
amount, whereby the fuel is properly injected so as to heat the
exhaust gas to a target temperature. At this time, the fuel
injection amount is controlled so that an amount of hydrocarbon
compound is 1.about.3000 ppm at the rear side of the burner 30 in
the flow direction of the exhaust gas.
[0056] That is, the controlling part 50 compares the temperature
measured through the temperature sensor 70 and decides whether to
inject the fuel, thereby deciding the detailed fuel injection
amount in consideration of the measured temperature and the target
temperature.
[0057] Furthermore, the controlling part 50 may decide the fuel
injection amount and whether to inject the fuel by additionally
using the RPM information of the diesel engine 10, as a condition
for deciding a vehicle state and a vehicle driving state.
[0058] Preferably, the controlling part 50 calculates an exhaust
emission rate and controls the fuel injection amount to be
0.001.about.0.02 g per 1 l of the exhaust emission rate for 1
minute.
[0059] The exhaust emission rate is calculated by an equation 1.
The exhaust emission rate is proportional to an engine displacement
and RPM of a vehicle, and a constant (a) of a load factor may be
varied according to the vehicle state. And the exhaust emission
rate may be calculated through repeated fuel injection
operations.
[Equation 1]
Exhaust emission rate (E)=aengine displacementRPM
[0060] (a=a constant of a load factor)
[0061] The exhaust emission rate obtained by the engine
displacement and the RPM uses as a main factor for deciding the
fuel injection amount. If there is no difference between the
temperature measured from the temperature sensor 70 and the target
temperature, the burner 30 is not operated, and if there is a large
difference therebetween, a large amount of fuel is injected within
a fuel injection range calculated by the equation 1, and if there
is a small difference therebetween, a small amount of fuel is
injected within the fuel injection range calculated by the equation
1.
[0062] That is, in the method for controlling an injection amount
of fuel in the aftertreating device of exhaust gas according to the
present invention, it is possible to decide the fuel injection
range in consideration of the vehicle state and also to decide the
precise fuel injection amount and whether to inject the fuel,
thereby efficiently reducing the noxious material of the exhaust
gas.
[0063] FIG. 3 is a graph of temperature changed by controlling a
fuel injection amount in the aftertreating device 100 of exhaust
gas in accordance with the present invention, and FIG. 4 is a graph
showing a change in temperature in a comparative example, wherein
the burner 30, the pro-catalyst 60 coated with platinum and the
cordierite catalytic filter 40 are provided at a truck having an
engine displacement of 6800 cc, as shown in FIG. 2, and the graphs
show each temperature at the front end of the pro-catalyst 60, the
rear end of the pro-catalyst 60 and the rear end of the filter in a
state that the target temperature is 480.degree. C.
[0064] All of the conditions are the same as shown in FIGS. 3 and
4. In FIG. 3, the controlling parts 50 controls the fuel injection
amount of the burner 30 using the temperature measured from the
temperature sensor 70 disposed between the pro-catalyst 60 and the
catalytic filter 40, and in FIG. 4, the controlling parts 50
controls the fuel injection amount by comparing the temperature
measured from the temperature sensor 70 disposed at the front end
of the pro-catalyst 60.
[0065] As shown in FIG. 3, in the method for controlling an
injection amount of fuel of the burner and the aftertreating device
of exhaust gas according to the present invention, a maximum
temperature is 530.degree. C. or less, and the temperature
distribution is relatively uniform, comparing with FIG. 4.
[0066] However, in the comparative example of FIG. 4, since the
maximum temperature is increased to 720.degree. C. , it is
apprehended that the durability is deteriorated.
[0067] The present application contains subject matter related to
Korean Patent Application No. 10-2009-0069951, filed in the Korean
Intellectual Property Office on Jul. 30, 2009, the entire contents
of which is incorporated herein by reference.
[0068] While the present invention has been described with respect
to the specific embodiments, it will be apparent to those skilled
in the art that various changes and modifications may be made
without departing from the spirit and scope of the invention as
defined in the following claims.
INDUSTRIAL APPLICABILITY
[0069] In the method for controlling an injection amount of fuel of
the burner and the aftertreating device of exhaust gas according to
the present invention, as described above, since the fuel injection
amount of the burner is controlled in consideration of the increase
in the temperature of the exhaust gas due to the pro-catalyst 60 or
the catalytic filter 40, it is possible to stably operate the
device, thereby efficiently reducing the noxious material of the
exhaust gas.
* * * * *