DE3328097A1 - Method for regenerating a soot burn-off filter for cleaning the exhaust gases of diesel engines - Google Patents
Method for regenerating a soot burn-off filter for cleaning the exhaust gases of diesel enginesInfo
- Publication number
- DE3328097A1 DE3328097A1 DE19833328097 DE3328097A DE3328097A1 DE 3328097 A1 DE3328097 A1 DE 3328097A1 DE 19833328097 DE19833328097 DE 19833328097 DE 3328097 A DE3328097 A DE 3328097A DE 3328097 A1 DE3328097 A1 DE 3328097A1
- Authority
- DE
- Germany
- Prior art keywords
- filter
- exhaust gases
- cleaning
- soot
- regenerating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000007789 gas Substances 0.000 title claims abstract description 37
- 239000004071 soot Substances 0.000 title claims abstract description 17
- 238000000034 method Methods 0.000 title claims abstract description 11
- 238000004140 cleaning Methods 0.000 title claims abstract description 5
- 230000001172 regenerating effect Effects 0.000 title claims description 5
- 230000008929 regeneration Effects 0.000 claims abstract description 14
- 238000011069 regeneration method Methods 0.000 claims abstract description 14
- 238000004904 shortening Methods 0.000 abstract description 3
- 238000007796 conventional method Methods 0.000 abstract 1
- 239000002245 particle Substances 0.000 description 13
- 238000006243 chemical reaction Methods 0.000 description 5
- 230000006378 damage Effects 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 235000002918 Fraxinus excelsior Nutrition 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 239000002956 ash Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 230000000747 cardiac effect Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 150000002611 lead compounds Chemical class 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
- F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
- F01N3/031—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters having means for by-passing filters, e.g. when clogged or during cold engine start
- F01N3/032—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters having means for by-passing filters, e.g. when clogged or during cold engine start during filter regeneration only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
- F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
- F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2410/00—By-passing, at least partially, exhaust from inlet to outlet of apparatus, to atmosphere or to other device
- F01N2410/04—By-passing, at least partially, exhaust from inlet to outlet of apparatus, to atmosphere or to other device during regeneration period, e.g. of particle filter
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B3/00—Engines characterised by air compression and subsequent fuel addition
- F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Processes For Solid Components From Exhaust (AREA)
- Filtering Of Dispersed Particles In Gases (AREA)
Abstract
Description
Verfahren zum Regenerieren eines Method of regenerating a
Rußabbrennfilters zur Reinigung von Dieselmotor-Abgasen Obwohl die Giftigkeit von Dieselmotor-Abgasen wegen ihres geringen Gehaltes an Kohlenmonoxyd und der Abwesenheit von Bleiverbindungen verhältnismäßig gering ist, macht sich der unter nicht optimalen Brennbedingungen gelegentlich entstehende Partikelgehalt des Abgases mitunter störend bemerkbar. Diese Partikel bestehen im wesentlichen aus Kohlenstoff (Ruß) mit adsorbierten flüssigen Kohlenwasserstoffen. Soot burn-off filter for cleaning diesel engine exhaust gases Toxicity of diesel engine exhaust gases due to their low carbon monoxide content and the absence of lead compounds is relatively small, makes itself the particle content that occasionally occurs under non-optimal firing conditions of the exhaust gas is sometimes noticeable. These particles essentially consist made of carbon (soot) with adsorbed liquid hydrocarbons.
Zur Entfernung dieser Partikel aus dem Abgas werden sogenannte Rußabbrennfilter eingesetzt, d.h., Filter, auf denen die Partikel niedergeschlagen werden Um eine Verstopfung der Filter zu vermeiden, müssen die niedergeschlagenen Partikel in regelmäßigen Abständen entfernt werden, was durch Reaktion der Partikel mit dem in den ..usput'gasen vorhandenen Luftsauerstoff gesciiietit.So-called soot burn-off filters are used to remove these particles from the exhaust gas used, i.e. filters on which the particles are deposited To avoid clogging of the filters, the precipitated particles must be regular Distances are removed, which is caused by the reaction of the particles with that in the .. output gases existing atmospheric oxygen.
Um aufwendige Herzvorrichtungen zum Erreichen der Reaktionstemperatur der Partikel, wie sie z.B. in DE-OS 29 51 316 oder DE-OS 30 17 784 beschrieben sind, zu vermeiden, wer- den diese Filter üblicherweise in Motornähe montiert, weil dort die Abgastemperatur am höchsten ist. Im Teillastbetrieb eines Verbrennungsmotors weist das Abgas jedoch nicht immer die zur Regenerierung des Filters erforderlichen hohen Temperaturen auf. Die Partikel lagern sich in diesen Betriebszuständen zunächst an der Oberfläche des Filters an, um dann während einer Betriebsperiode im Vollast- oder oberen Teillastbereich bei entsprechend hohen Temperaturen des Abgases zu verbrennen.To elaborate cardiac devices to reach the reaction temperature the particles, as described, for example, in DE-OS 29 51 316 or DE-OS 30 17 784, to avoid being which these filters are usually mounted near the engine, because the exhaust gas temperature is highest there. In partial load operation of an internal combustion engine However, the exhaust gas does not always have what is necessary to regenerate the filter high temperatures. The particles are initially stored in these operating states on the surface of the filter, to then be used during an operating period at full load or to burn the upper part-load range at correspondingly high exhaust gas temperatures.
Diese Reaktion der auf dem Filter befindlichen Partikel hält jedoch nur solange an, wie das Abgas auch die erforderliche Temperatur besitzt. Sinkt also die Abgastemperatur wieder, bevor sämtliche niedergeschlagenen Partikel reagiert haben, so kann das Filter nicht vollständig regeneriert werden.However, this reaction of the particles on the filter lasts only as long as the exhaust gas has the required temperature. So sinks the exhaust gas temperature again before all the precipitated particles react the filter cannot be completely regenerated.
Es besteht daher die Aufgabe, ein Verfahren zum Regenerieren eines Rußabbrennfilters zur Reinigung von Dieselmotor-Abgasen zu finden, mit dem das Abbrennen des sich auf dem Rußfilter befindlichen Rußes beschleunigt werden kann und was dadurch ein öfteres, vollständiges Regenerieren des Filters auch bei nur kurz dauernden Temperaturspitzen ermöglicht.There is therefore the object of a method for regenerating a To find soot burn-off filters for cleaning diesel engine exhaust gases, with which the burn-off the soot on the soot filter can be accelerated and what that means frequent, complete regeneration of the filter, even if it only lasts for a short time Allows temperature peaks.
Diese Aufgabe wird durch das in den Patentansprüchen beschriebene Verfahren gelöst. Es konnte gefunden werden, daß sich die Reaktionsgeschwindigkeit der auf dem Filter niedergeschlagenen Partikel erheblich steigern läßt und damit die für die Regenerierphase erforderliche Zeit verkürzen läßt, wenn während dieser Regenerierphase die Geschwindigkeit der das Filter durchströmenden Gase gesenkt wird. Diese Verkürzung er fc 1 gt sowoll i Rt Pti[#- abbrennfiltern mit als auch ohne katalytische Beschichtung. Besonders günstig ist es, wenn die G1eschwindigkeit der claus Filter durchströmenden Gase während der Regenerierphase auf 25% bis 50% der normalen Gasgeschwin -digkeit gesenkt wird. Am vorteilhaftesten erfolgt die Senkung der Gasgeschwindigkeit während der Regenerierphase dadurch, daß ein Teil der Auspuffgase mittels einer Nebenstromleitung an dem Rußabbrennfilter vorbeigeleitet wird. Die Regenerierung des Rußabbrennfilters kann im Prinzip immer dann erfolgen, wenn das Abgas die zur Reaktion der Rußteilchen erforderliche hohe Temperatur besitzt. Zweckmäßiger ist es jedoch, eine Regenerierung des Rußabbrennfilters unter Herabsetzen der Gasgeschwindigkeit nur dann vorzunehmen, wenn sich vor dem Rußabbrennfilter infolge der Beladung des Filters mit Ruß ein bestimmter Gegendruck aufgebaut hat. Der Druck kann mittels einer Druckmeßdose im Auspuff st rang vor dem Filter ermittelt werden, wobei bei Überschreiten eines bestimmten Drucks im Auspuffstrang bei gleichzeitigem Vorliegen einer geeigneten Auspuffgastemperatur ein Ventil zur Nebenstromleitung geöffnet wird. Der Druck, bei dem die Nebenstromleitung geöffnet und ein Teil des Abgases an dem zu regenerierenden Filter vorbeigeleitet wird, hängt von der Größe und Art des verwendeten Filters ab und muß je nach dem verwendeten Filter individuell bestimmt werden Als Anhaltswert kann jedqch angegeben werden ~daß die ~ Öffnung der Nebenstromleitung zur Beschleunigung der Regenierung sp@testens dann durchgeführt werden sollte, wenn der Druckanstieg gegenuber dem nichtbeladenen Eilter 0,4 bis 0,6 betragt.This object is achieved by what is described in the claims Procedure solved. It was found that the reaction rate the particles deposited on the filter can be increased considerably and thus the time required for the regeneration phase can be shortened if during this Regeneration phase, the speed of the gases flowing through the filter is reduced will. This shortening er fc 1 gt as well i Rt Pti [# - burn down filters with and without a catalytic coating. It is particularly favorable if the G1speed of the gases flowing through the claus filter during the regeneration phase is reduced to 25% to 50% of the normal gas speed. Most beneficial the gas velocity is reduced during the regeneration phase by that part of the exhaust gases by means of a bypass line to the soot burn-off filter is passed by. The regeneration of the soot filter can in principle always occur when the exhaust gas is as high as necessary for the reaction of the soot particles Temperature. However, it is more expedient to regenerate the soot-burning filter by reducing the gas velocity only if before the Soot burn-off filter a certain counter pressure due to the loading of the filter with soot has built. The pressure can be achieved by means of a pressure cell in the exhaust pipe the filter can be determined, with exceeding a certain pressure im Exhaust line with simultaneous presence of a suitable exhaust gas temperature a valve to the bypass line is opened. The pressure at which the bypass line opened and some of the exhaust gas bypassed the filter to be regenerated depends on the size and type of filter used and must depend on the The filters used can be determined individually. Any reference value can be specified be ~ that ~ the ~ opening of the bypass line to accelerate the regeneration should be carried out at the latest when the pressure rises compared to the unloaded Eilter is 0.4 to 0.6.
Durch das erfindungsgemäße Verfahren lassen sich eine Reihe von Vorteilen erreichen. Durch das schnellere Abbrennen des Rußfilters wird das Filter öfter voll regeneriert, d.h., das Abgasgegendruckniveau wird abgesenkt und dadurch werden sowohl der Verbrauch als auch das Fahrverhalten günstig beeinflußt. Die unmittelbar auf dem Filter angesammelte Partikelmenge ist nicht mehr so groß.Dadurch wird aber die thermische Belastung des Filters beim Regenerieren kleiner und eine Zerstörung oder Schädigung des Filters durch Schmelzen der Filteroberfläche infolge zu hoher Temperaturen verhindert.The method according to the invention offers a number of advantages reach. As the soot filter burns down more quickly, the filter becomes full more often regenerated, i.e. the exhaust gas back pressure level is reduced and thereby both the consumption as well as the driving behavior has a favorable influence. The immediately on The amount of particles that has accumulated in the filter is no longer that large thermal load on the filter when regenerating smaller and destruction or Damage to the filter through melting of the filter surface as a result of excessively high temperatures prevented.
Zusätzlich kann auch durch die Nebenstromleitung verhindert werden, daß überhaupt ein zu hoher Abgasgegendruck auftritt. Auch wenn das Filter z.B. durch Schwermetalle und Asche infolge der Verwendung minderwertiger Kraftstoffe völlig verstopft ist, was ansonsten durch den stark ansteigenden Abgasgegendruck zum Stillstand des Motors führen würde, bleibt der Motor immer noch durch Öffnung der Nebenstromleitung, wenn auch mit verminderter Leistung, lauffähig.In addition, the bypass line can prevent that an excessively high exhaust gas back pressure occurs. Even if the filter is e.g. Heavy metals and ashes completely as a result of using poor quality fuels is clogged, which would otherwise come to a standstill due to the sharp rise in exhaust gas back pressure of the engine, the engine still remains by opening the bypass line, albeit with reduced performance, executable.
Beispiel: Ein Fahrzeug ausgerüstet mit einem 2.0 1 4-Zylinder-Dieselmotor wurde auf einer ebenen Teststrecke mit 80 km/h so lange gefahren, bis sich vor dem Rußabbrennfilter ein Ahgasgegendruck von 0.S bar aufgebaut hatte.Example: A vehicle equipped with a 2.0 1 4-cylinder diesel engine was driven on a level test track at 80 km / h until the The soot burn-off filter had built up a gas counter pressure of 0.S bar.
Danach wurde der Wagen voll beschleunigt und die Wegstrecke gemessen, die für ein vollständiges Abbrennen des Filters benötigt wurde. Die Wegstrecke betrug ca. 1100 m.Then the car was fully accelerated and the distance measured, which was required for the filter to burn down completely. The distance was approx. 1100 m.
In einem zweiten Versuch wurde das Filter in der gleichen Art beladen. Während der anschließenden Beschleunigung wurde jedoch die By-Pass-Leitung des Filters geöffnet, wodurch die Geschwindigkeit der das Filter durchströmenden Gase auf ca. 50% der normalen Geschwindigkeit gesenkt wurde. In diesem Fall wurde ein vollständiges Abbrennen des Filters schon nach ca. 700 m erreicht.In a second attempt the filter was loaded in the same way. During the subsequent acceleration, however, the filter's by-pass line became opened, whereby the speed of the gases flowing through the filter is reduced to approx. Reduced 50% normal speed. In this case a complete The filter burns out after approx. 700 m.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19833328097 DE3328097A1 (en) | 1983-08-04 | 1983-08-04 | Method for regenerating a soot burn-off filter for cleaning the exhaust gases of diesel engines |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19833328097 DE3328097A1 (en) | 1983-08-04 | 1983-08-04 | Method for regenerating a soot burn-off filter for cleaning the exhaust gases of diesel engines |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| DE3328097A1 true DE3328097A1 (en) | 1984-08-16 |
Family
ID=6205716
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DE19833328097 Withdrawn DE3328097A1 (en) | 1983-08-04 | 1983-08-04 | Method for regenerating a soot burn-off filter for cleaning the exhaust gases of diesel engines |
Country Status (1)
| Country | Link |
|---|---|
| DE (1) | DE3328097A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0188267A1 (en) * | 1985-01-14 | 1986-07-23 | Mazda Motor Corporation | Exhaust gas cleaning system for vehicle |
| EP0528289A1 (en) * | 1991-08-09 | 1993-02-24 | Nippon Soken, Inc. | Device for catching and removing particulates for a diesel engine |
-
1983
- 1983-08-04 DE DE19833328097 patent/DE3328097A1/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0188267A1 (en) * | 1985-01-14 | 1986-07-23 | Mazda Motor Corporation | Exhaust gas cleaning system for vehicle |
| EP0528289A1 (en) * | 1991-08-09 | 1993-02-24 | Nippon Soken, Inc. | Device for catching and removing particulates for a diesel engine |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| OAV | Applicant agreed to the publication of the unexamined application as to paragraph 31 lit. 2 z1 | ||
| OP8 | Request for examination as to paragraph 44 patent law | ||
| 8130 | Withdrawal |