CN201277081Y

CN201277081Y - Diesel oil particulate converter used for processing diesel oil waste gas particle matter

Info

Publication number: CN201277081Y
Application number: CN 200820115326
Authority: CN
Inventors: 里法特·卡梅尔
Original assignee: RIFAT CARMEL
Current assignee: RIFAT CARMEL
Priority date: 2007-05-25
Filing date: 2008-05-26
Publication date: 2009-07-22
Anticipated expiration: 2018-05-26
Also published as: ZA200908014B; CN201265441Y

Abstract

The utility model provides a diesel particle converter for treating diesel exhaust gas particle substances, which relates to the field of equipment for after-treatment of diesel engines. The converter is used to collect and cremate particle substances from exhaust gas of the diesel engine, which aims to resolve the problem of low collection and cremation efficiency of the particle substances in the prior art. The converter comprises an exhaust gas channel, a casing, at least one filter element, an electrical burner and a pulse power source, wherein the exhaust gas extends from the diesel engine to pass through the particle converter, the filter element is located in the casing, and the pulse power source is connected to the electrical burner to cremate collected coal smoke.

Description

Be used to handle the diesel particulate transducer of diesel exhaust particulate matter

Technical field

The utility model relates generally to the equipment for after-treatment that is used for diesel engine and natural gas engine.More specifically, the utility model relates to agglomeration and the delay of particulate matter in clad metal wire net filtration core.More specifically, the utility model also relates to by reliable and controlled process and incinerating.

Background technique

The particle trapper of diesel engine exhaust is accepted widely, and is used for the road emissions of diesel engines to be consistent with various statutory regulations.The equipment particle trapper is also known in diesel engine is used for aspect particulate matter and tiny particulate matter---current USEPA regulation for PM10 and PM2.5 standard---and improves ambient air quality.Particle trapper can be realized the remarkable minimizing of particulate, and it can reach 90% to 95%.Traditional particle trapper (for example straight-through type catcher and wire gaze particle trapper) must be carried out processing to burn the particulate matter that gathers and to make equipment return to original state.Regeneration is the coal smoke that gathers of burning and makes pottery or the filter of wire gaze returns to original state to begin the process of another coal smoke loaded cycle etc.

Commonly assigned U.S. Patent No. 7,266,943 has been described the alternative of the regenerative process that is called incineration course.With U.S. Patent No. 7,266,943 full text is incorporated into herein in this mode of passing through reference.Though proved U.S. Patent No. 7,266,943 teachings of incinerating for particulate matter are successful, and this technology still needs to make the improvement of continuation.

The model utility content

Complex metal wire-mesh medium collection, agglomeration and discharge large-sized agglomeration particulate, these micro particle filterings form the coal smoke caking being detained online.Be detained net and be connected to pulse dc power, and reaching the long-pending piece density (accumulation) of specific coal smoke power connection when---it is represented by the resistance between delay net and the upstream grounded screen---.By being incorporated into traditional diesel oxidation catalyst in complex metal wire-mesh medium the place ahead, perhaps pass through at the integrally formed catalysis net in complex metal wire-mesh the place ahead, the NO of part converts NO to ₂When caused to incinerate need the time, incineration course begins and continues.

Incineration used herein is defined as the slow process that is used for the collected coal smoke of oxidation as required.Should there be enough coal smokes to be trapped on the complex metal wire-mesh medium to guarantee high particulate reduction efficiency.The oxidation heat that is produced is by exhaust gas dilution, thus in the waste gas not significantly or can detected temperature increase.On the other hand, regeneration is a such process: it is all burned and be accompanied by usually and reach 700 ℃ or higher tangible temperature and raise that wherein all accumulate in coal smoke on the filter medium.

The utility model relates to a kind of method effectively, efficiently and reliably that is used to incinerate the agglomeration particulate matter that comes from diesel exhaust.The design of burner depends on the coal smoke substance trapping of agglomeration online in the delay of for example fine groove net (Dutch-screen), thereby forms caking at upstream side.The fine groove net is attached to pulse dc power, is ground connection and cooperate net.Be the isolation mounting of the ceramic-base of line or net form formula by insertion, it is constant that the gap between these two nets keeps.Space in the gap remains minimum particle size.The clearance gap of size between 0.010 to 0.025 inch (0.25 to 0.62 millimeter) is favourable, is preferably gap among a small circle, because reduced particle size to be incinerated.Have been found that from the pulse direct current electric current of 12v or higher power supply and an amount of NO ₂, the combination that is higher than 200 ℃ exhaust gas temperature and is embedded in the base metal catalysts in the burner gap is effective for incinerating coal smoke.When exhaust gas temperature was elevated to 300 to 375 ℃ scope, incineration course quickened, and coal smoke incinerates fast.But incineration defined herein still than regenerative process slowly many.As a result, can not observe the obvious temperature of incinerating in the by product and raise, and the maximum temperature that incineration net (fine groove net) is located is lower than 500 ℃.This mainly is because waste gas has cooled off the heat that produces by incinerating.In case the size of caking is owing to the coal smoke oxidation reduces, then the increase of burner resistance makes power supply stop, and forms again to carry out new circulation up to another coal smoke layer.

Another feature of the present utility model is that oxidation catalyst and particulate transducer are integrally formed.This realizes by the upstream side that the noble coatings anastomose is combined in the complex metal wire-mesh medium.This net comprise some winding apparatus cores around layer, to allow a large amount of collisions and the interaction between waste gas and the precious metal position.But under some engine operation state, the existence of this net can produce some spark or overheated zone, and it will light the coal smoke that is captured in the complex metal wire-mesh.Though this incident is a low probability event, it can destroy the wire gaze medium.Therefore, the fine groove stainless (steel) wire that is used as arc arrester is around precious metal network, with the possibility that prevents that coal smoke from lighting.

Owing to adopted noble metal catalyst, some SO ₂Be transformed into sulphate (particulate), and the nitrous oxide (NO) of part is transformed into nitrogen dioxide (NO ₂).Sulphate and NO ₂It is the pollutant of not expecting.But, because system's setting causes the long residence time of waste gas and capture coal smoke interaction (estimating average 100 times) from the ceramic wall to the microparticles collection device with combining of thick bed structure thereby hang down exhaust gas velocity.Population effect is that in fact sulphate revert to sulfur dioxide (SO ₂), some coal smokes in the complex metal wire-mesh are incinerated and in fact from NO ₂Be converted to NO and nitrogen.NO ₂And a large amount of interactions between the coal smoke also can cause NO in the wire gaze ₂In O ₂All discharge, cause NO _xReduction, it depends on that the temperature estimation reaches 10-15%.Population effect is that the discharging degree that the sulphate do not expected and nitrogen dioxide pollute improves.According to a special aspect, the utility model provides a kind of system of particulate matter with the waste gas of clean diesel motor that be used to collect and incinerate.This system comprises diesel particulate transducer (DPC), and it has housing and at least one is arranged in the filter core of crossing of housing.Exhaust passageway extends through DPC from diesel engine.Diesel oxidation catalyst (DOC) is arranged in the exhaust passageway.At least one waste gas cooling equipment is set to be used to control exhaust gas temperature.Feedback control system is based on following controlling factors exhaust gas temperature, and described factor comprises the pressure drop of DPC, the temperature and the engine RPM in DPC the place ahead.

According to another special aspect of the present utility model, the utility model provides a kind of NO of particulate matter ₂Incineration is with the method for the waste gas of clean diesel motor.This method comprises diesel particulate transducer (DPC) is set that it has housing and at least one is arranged in the filter core of crossing of housing.Diesel engine exhaust is via the exhaust passageway that extends through DPC from diesel engine, and handled by the diesel oil oxidation catalyst converter (DOC) that places exhaust passageway.Feedback control system is controlled exhaust gas temperature according to the pressure drop of DPC, the temperature and the engine RPM in DPC the place ahead by optionally controlling the waste gas cooling equipment.According to another special aspect, the utility model provides a kind of diesel particulate transducer, it is used to incinerate the particulate matter from diesel engine exhaust, described diesel particulate transducer defines the exhaust passageway that extends through DPC from diesel engine, and comprise housing, at least one be arranged in housing cross filter core and electric incineration system, described electric incineration system is suitable for being electrically connected to pulse power supply to be used for incinerating the coal smoke that was collected in filter core.

According to another special aspect of the present utility model, the utility model provides a kind of electricity to incinerate the method for particulate matter with the waste gas of clean diesel motor.This method comprises provides diesel particulate transducer (DPC), and it has housing and at least one is arranged in the filter core of crossing of housing, and makes diesel engine exhaust via the exhaust passageway that extends through DPC from diesel engine.The coal smoke of agglomeration is collected at least one and crosses in the filter core.The coal smoke of agglomeration incinerates by the electric incineration system that is electrically connected to pulse power supply.

Description of drawings

The accompanying drawing of this paper only is used for purpose of description, all is not intended to limit scope of the present utility model in any case.

Fig. 1 is the longitdinal cross-section diagram that is used to incinerate the particulate transducer of diesel engine exhaust particulate matter according to the utility model, shown in the particulate transducer comprise the single filter core of crossing.

Fig. 2 is that the line 2-2 along Fig. 1 cuts open the sectional view of getting.

Fig. 3 is the detailed sectional view of a part of the burner of the utility model particulate transducer.

Fig. 4 is the schematic representation of control setting that is used for the DC power-supply system of the utility model particulate transducer.

Fig. 5 is the schematic representation of operation cycle that is used for the pulse dc power of the utility model particulate transducer, and this particulate transducer comprises a plurality of filter cores of crossing.

Fig. 6 is and the similar longitdinal cross-section diagram of Fig. 1 that it illustrates the particulate transducers that comprise a plurality of mistake filter cores according to of the present utility model.

Fig. 7 is that the line 7-7 along Fig. 6 cuts open the sectional view of getting.

Fig. 8 is illustrated in the effectively schematic representation of the probability of incineration takes place in the typical diesel engine operation cycle.

Fig. 9 be illustrated in 300 ℃-330 ℃ when incinerating typical consequence and the schematic representation of back pressure corresponding reduction in time.

Figure 10 is the schematic representation that is used for the exhausted gas post-processing system of diesel engine, and diesel particulate is shown in this system and the diesel engine place of working is interconnected.

Embodiment

Character described below only is exemplary, is not intended to limit the utility model, application or purposes.Should understand, in institute's drawings attached, corresponding reference character is in order to represent identical or corresponding parts and feature.Though the explanation of this paper and concrete arbitrarily example have been described mode of execution of the present utility model, they only are to be not intended to limit scope of the present utility model for illustrative purposes.In addition, the description for a plurality of mode of executions with described feature is not other mode of execution that is intended to get rid of other mode of execution with further feature or the various combination that is combined with described feature.

Generally referring to accompanying drawing---wherein reference character is represented identical or corresponding parts in all views, illustrates and indicates with reference character 10 generally according to the utility model diesel particulate transducer (DPC) structure, described system.Particulate transducer 10 of the present utility model can be used for having the explosive motor of a large amount of sub-micron or nanosized particles---for example diesel engine, compressed natural gas motor or LNG Liquefied natural gas motor.Particulate transducer 10 can comprise that at least one crosses filter core 12.For example, Fig. 1 shows and has the single particulate transducer 10 of crossing filter core 12.Fig. 6 shows has a plurality of particulate transducers 10 of crossing filter core 12.

A. cross filter core

Specifically see figures.1.and.2, the filter core 12 of crossing that particulate transducer 10 is shown is installed in the housing 14, and the waste gas that enters can be assigned to equably the inner core of crossing filter core that is limited by tubular member 26 usually.With regard to the utility model, it is conventional should understanding housing 14 and cross the installation of filter core 12 in housing 14, thereby describes no longer in addition at this.

It is interconnected with power supply 16 places of working that Fig. 1 illustrated filter core 12.This system can comprise the diesel oil oxidation catalyst converter (DOC) in the exhaust passageway.As shown in the figure, cross filter core 12 and can be combined with DOC.In addition, cross filter core 12 and can comprise blow-out net 20, complex metal wire-mesh cyclone agglomerator 22 and electric burner 24 usually.DOC cooperates with the engine exhaust temperature distribution to produce sufficient NO ₂, the coal smoke on the coal smoke caking that is used to incinerate complex metal wire-mesh cyclone agglomerator 22, burner gap 45 and be detained screen 42 upstream sides.

Cross filter core 12 and can comprise the generally tubular member 26 that limits inlet 28 and outlet 30.For example 28 introduced filter core 12 by entering the mouth in the direction of arrow A from the untreated exhaust gas of diesel engine.Crossing filter core 12 can be interconnected with flow distributor 32.Flow distributor 32 can be installed in the member 26 and operate to guide untreated exhaust gas Radial Flow equably.Flow distributor 32 can have the shape of general conical or cylindricality.

Tubular member 26 along being provided with porose on the major component of its length direction so that waste gas radially flow.This layout makes that the exhaust flow prompt drop is low, can regulate the waste gas flow velocity by suitably selecting the effective filter core perforation length of crossing.

If can illustrate particularly in the sectional view of the Fig. 2 that crosses filter core 12, the diesel oil oxidation catalyst converter can be a body component of filter core 12, and can be configured to one or more layers filter screen 18.A kind of suitable filter screen 18 known in the art is the fine groove net.But also can use other net.In the remaining part of this specification, should understand, in scope of the present utility model, all alternative with other net materials known in the field to quoting arbitrarily of fine groove net.

Radially the fine groove net 18 of multilayer can comprise opening, the size that opening is set with gathering of coal smoke caking is restricted to minimum, and form crooked flow path with stop and the unburned fuel of cooling down high-temperature to prevent to filter the spontaneous combustion in the core 12.Though can use the layer that radially is provided with of any amount, in specific implementations, the number of plies of fine groove net can comprise 2 to 5 around layer.Net 18 can be coated with platinum with collision and exchange between the catalytic site of strengthening gas and net.It is long-pending to increase catalytic surface that described net also can have the washcoat layer of aluminium for example.Alternatively, noble metal catalyst can directly be applied on the wire netting by electroplating.Therefore catalysis fine groove net 18 is as the diesel oil oxidation catalyst converter.But it is formed in the same filter core structure.In addition, net can or be fabricated to the wire gaze matrix that limits a rigidity by sintering, brazing.

The DOC that makes with the wire gaze matrix (wire of braiding or the wire of cutting) of rigidity has further strengthened catalytic reaction and has improved performance.Traditional DOC is made of metal or ceramic direct current channel, and it can reach 200 passages or more per square inch.This undersized flow channel converts exhaust flow to laminar condition from turbulent flow.For the reaction between waste gas and the catalytic site, laminar condition is not effective.On the other hand, rigid metal silk screen matrix has been strengthened turbulent flow and has been increased local turbulence.This can increase catalysis, reduces the applied amount of precious metal and improve catalytic performance.

Catalysis net 18 can advantageously reduce cost by deducting part and solving spatial constraints in some applications.Depend on exhaust gas temperature, net 18 further provides HC and CO reduction, and NO is converted into NO slowly ₂The worst influence of integrally formed this net relate to reduce waste gas temperature to prevent to filter the coal smoke spontaneous combustion in the core, this has reduced the efficient of catalytic activity.But, reduce peak temperature and can prolong life of catalyst.

Cross filter core 12 and can comprise second radial layer that is mid-level net 20 forms in addition.Mid-level net is used as arc arrester after can being inserted in fine groove net 18.Blow-out net 20 can use interchangeably with thermostabiliser.Net 20 may be selected to has wide opening so that coal smoke gathers and minimizes and have any overheated zone that crooked flow passage is produced by catalytic reaction with cooling.To a certain extent, arc arrester 20 can be used as the buffer between precious metal network 18 and complex metal wire-mesh or the wire gaze cyclone agglomerator 22, with the possibility of obvious reduction coal smoke spontaneous combustion.Complex metal wire-mesh medium 22 can be positioned at after the arc arrester 20.In this respect, cross filter core 12 and comprise the 3rd radial layer that is wire gaze cyclone agglomerator 22 forms.

Cross filter core 12 and can comprise the grounded screen 36 that radially is positioned at wire gaze medium 22 outsides in addition.Grounded screen 36 can limit bigger opening.For example grounded screen 36 can comprise that with complex metal wire-mesh 22 be 40 * 40 plain weave nets of reeling in the center.One or more is acceptable around layer.The particulate that net 36 can allow agglomeration by but provide enough ground connection to electrically contact for the coal smoke that is captured in the burner 24.

Crossing filter core 12 and can comprise ceramic-base isolator 40 in addition, is thereafter fine groove net 42.Burner 24 can be limited by grounded screen 36, isolator 40 and fine groove net 42.Base metal catalysts 44 can also be embedded in the burner 24.The function of ceramic isolators 40 is to provide electrical insulation between outmost fine groove net 42 and the grounded screen 40 by setting up fixed interval (FI) 45.Ceramic isolators 40 can adopt the form of ceramic thread or ceramic network, and should provide wide open area to lump to allow forming coal smoke in burner gap 45.Burner gap 45 may be defined as the radial distance between net 36 and the net 42.

The size in gap 45 may be selected to as far as possible little.Aspect this, minimum size is subjected to causing the restriction of the manufacturing dimension tolerance of short circuit current.The minimum clearance size can be approximately 0.01 inch (0.25 millimeter), although if reached stricter manufacturing tolerances then can adopt littler gap.Though the gap that increases may not expected, may is acceptable in some applications up to about 0.02 inch (0.5 millimeter) or bigger size gap.

Fine groove net 42 may be selected to has little opening.Aspect this, these openings can be about 70 microns opening, with the particulate and the formation caking of catching agglomeration effectively.Size from the agglomeration soot particles of complex metal wire-mesh medium 22 can reach 100 microns or bigger.Can easily catch these big particulates at the upstream side of fine groove net.The thickness that gathers of the long-pending piece of evidence coal smoke repeatedly reaches above 0.5 millimeter.Low exhaust gas velocity helps the formation of long-pending piece in the burner.Can select to cause the road of different exhaust gas velocity or the circulation of cross-country power operation to guarantee in most times correctly catching of coal smoke caking in the burner.Remain little caking thickness and help increasing the coal smoke filter efficiency.

Along with coal smoke caking continue gather, its thickness increases, and fills up the burner gap up to the long-pending piece of coal smoke.Though coal smoke deposits not complete and homogeneous, the density of the long-pending piece of coal smoke is gathered with coal smoke and is increased.In case the long-pending piece contact of coal smoke grounded screen 36 then can cooperate between the net at two to form resistance.The filling density that depends on coal smoke, resistance reduces along with the increase of coal smoke filling.For example, the resistance of crossing on the filter core 12 long at 18 inches and three inches burner diameter reaches one or two ohm.The resistance of finding the long-pending piece of measured identical coal smoke in addition increases along with exhaust gas temperature and reduces significantly, causes incinerating faster.Wire gaze cyclone agglomerator 22, burner gap and be detained net 42 and cooperate to limit a thick bed of material that is used to collect the coal smoke that stops when long.

Helping the long-pending piece incineration of coal smoke mainly to have benefited from being applied to the power supply of fine groove net and get access to grid causes coal smoke slowly to incinerate.Use direct current and ac power supply to test, find that ac power supply is more effective to beginning and continuation incineration course.Discovery is for little burner gap and be higher than that low voltage is effective for 200 ℃ the temperature.Main target is to make power supply generally to be used for 12 volts of direct currents of most of automobile situations.This causes the development of pulse power supply.But higher supply voltage also is acceptable, although may not expect above 60 volts voltage.

Fig. 6 and 7 illustrates according to another kind of particulate transducer 10 of the present utility model.The difference of Fig. 6 and 7 mode of execution and aforementioned embodiments is that it is combined with a plurality of filter cores 12 of crossing.Similarly reference character is in order to the like between the expression mode of execution.As shown in the figure, particulate transducer 10 can comprise that three are crossed filter core 12.But should understand, in scope of the present utility model, can use the filter core 12 excessively of more or less quantity.For big diesel engine---for example diesel generator, locomotive and offshore set-up etc., the quantity of crossing filter core can be big as required.

B. power supply

Forward Fig. 3 and 4 to, but be used for the power supply DC electrical source 16 of particulate transducer 10.But the DC electrical source of DC electrical source 16 12 or 24 volts.DC electrical source 16 can supply to circuit breaker 50.Circuit breaker 50 can be the circuit breaker 50 of variable frequency and dutycycle, and its output supplies to big current output device 52.Big current output device 52 can be electrically connected to burner fine groove net 42.

Particulate transducer 10 can comprise in addition and be used to control the passive control system that applies the incineration power supply or install 60.Control gear 16 can comprise the control logic that is used for monitoring continuously burner 24 resistance.When the burner supply disconnecton, another comprises that size is the circuit of 400 to 500 ohm the resistance joint of can connecting with the burner circuit.This circuit can be with 12 volts of DC power supply, and electric quantity consumption can very little (for example near 0.1 watt).The resistance of burner is represented in the measurement of burner 24 voltages.High burner voltage is represented high burner resistance, and vice versa.When burner 24 resistance drop to when being lower than predetermined value or setting threshold, big current output device 52 can trigger to engage burner 24.Supply pulse direct current, and can be rushed to burner 24, incinerate the long-pending piece of coal smoke up to about 30 to 40 amperes electric current.The time span of the sustainable preliminary election of power cycles.The time span of preliminary election can be little, for example about 5 minutes.When loop ends, remeasure the resistance of burner 24, and when it is lower than preset threshold, begin another power cycles immediately, incinerated up to coal smoke---its resistance by burner 24 increases to and is higher than threshold value and represents.Although threshold value depends on the burner surface area, typical resistance is 0.5 to 1.0 ohm.Big surface area has low threshold value, and vice versa.

Power supply scalable be used for a plurality of cross filter cores situation---it is typical in big diesel engine.Fig. 5 illustrates the power cycles that is used for many filter cores particulate transducer 10 (as shown in Fig. 6 and 7).Power supply can preset time (for example 10 minutes) order engage filter core 12, measure one then and cross the resistance at filter core 12 places and continue to start new power cycles or not.

C. incineration course and operation

At the incineration course that this limited is a process slowly, wherein collected be stored in complex metal wire-mesh 22, burner gap 45 in be detained net 42 upstream sides on coal smoke all oxidablely become innocuous substance, mainly be CO ₂And H ₂O.Because coal smoke oxidation liberated heat is by exhaust gas dilution.There are four factors that can help incineration course to finish smoothly.These factors can comprise: 1) moderate exhaust gas temperature; 2) micro-NO ₂Generation; 3) in burner, adopt base metal catalysts; And 4) pulse direct current accessory power supply.The combination of described four factors can help all to realize effective incineration of high statistical probability in nearly all driving/operation cycle of diesel engine.Population effect is the balance that realizes between collected and the coal smoke that incinerated.Excessive coal smoke is collected or excessive coal smoke incineration both of these case is not expected.Should understand, the utility model can be used for the multiple system that does not comprise all these four kinds of factors.Low when reaching 200 ℃ temperature, take place to incinerate but incineration speed is much lower.Near 350 ℃ temperature the time, incinerate completely by having base metal catalysts and NO ₂Realize.When exhaust gas temperature reaches 350 ℃, do not need electricity to incinerate, and therefore power circuit breaker cut off automatically.In the transducer ingress usually had 350 ℃ the application of exhaust gas temperature reading, this can be reduced to fuel consumption a low degree effectively at some---be estimated as 0.1%.

Though power supply can provide sufficient heat to keep incineration, low exhaust gas temperature (for example about 100 ℃) makes that incineration is very slow and insufficient.The probability of happening of power operation situation was very low in this long---for example 30 to 50 hours---.In real life, because effective incineration that for a long time low exhaust gas temperature causes can not cause the increase of filter core back pressure completely.If this situation further prolongs, then big soot particles is released in the atmosphere to discharge the high back pressure of a part by burner fine groove net on the burner.The size of the particulate of these releases is big, and drops on outside the limited range of PM 10 and PM 2.5, and like this, they do not constitute the particle contamination of qualification.In addition, the particulate transducer can not disturb power operation under this low probability event, can not cause stopping up in most of filter mediums yet.

The particulate memory space of complex metal wire-mesh medium 22 and burner 24 is big.This makes compares too abnormal power operation situation with ceramic catcher---for example long-time idle running or low engine load---, and the influence to engine performance is more not serious.In case engine load increases and exhaust gas temperature surpasses 300 ℃, then corrects normal back pressure.

Should be noted that the electric quantity consumption that is the pulse direct current form ad hoc is used to heat coal smoke, and have O ₂And NO ₂Situation under, it makes incinerator be shaped on effect.But, may meet with electric heating loss, because 1) and exhaust flow cooling effect and 2) resistance of burner part is higher relatively, and the electric current that is caused is low and and then incinerates slack-off.By monitoring burner resistance constantly, the pulse power supply is automatically connected when the incineration probability is high.This is restricted to low-down degree with electric quantity consumption, and under most of automobile situations, the fuel consumption of estimation is about 0.1%.When reach 300 ℃, maximum during in transducer ingress exhaust gas temperature up to 375 ℃---this is very common in most of automobile situations, uses NO ₂It is auxiliary to come the oxidation coal smoke to need not electric power with regard to being enough to clean the coal smoke that is gathered continuously.Usually hypothesis this 300-375 ℃ temperature can occur in the time of 10-20%.In the driving that is lower than 300 ℃ circulates, along with demand raises, power supply will automatically be assisted incineration.

Base metal catalysts is implemented with the form of wire or net, but and single element or its compounds of planting such as application examples such as iron, copper, vanadium, calcium, magnesium.Catalyzer can be the form of coiling, perhaps is around the form of the net of ceramic thread or net (not shown) upstream.The selection of base metal catalysts is that it can oxidation promptly in this operating environment.Therefore, the thickness of catalyst gauze should be very little so that the total thickness in burner gap minimize.This standard makes the thickness of metallic catalyst most preferably be about 0.005 inch (0.1 millimeter).Base metal catalysts is effectively for reducing the coal smoke ignition temperature, thereby helps very much incineration course.

Forward the schematic representation of Figure 10 to, what illustrate is the after-treatment system 100 that is used for according to the diesel engine of the utility model structure.It is interconnected with diesel engine 102 places of working that system 100 is shown.Diesel engine 102 is any type, but can comprise having the diesel engine that high exhaust gas temperature distributes especially.

Diesel engine exhaust can be incorporated into system 100 by cooling tube 103.Radiation cooled tube 103 can be designed to maximum temperature is restricted to a medium degree.Aspect this, about 700 ℃-750 ℃ exhaust gas temperature can be reduced to for example about 400 ℃.

The motor of experience transient operation pattern---for example the situation of automobile---can be in conjunction with the thermostabiliser with high thermal inertia.Aspect this, thermostabiliser 104 can be provided for the fluctuation of leveling exhaust gas temperature.This stabilizer can be made of providing high thermal inertia, high breathability reducing pressure drop the sintering braided metal line with enough weight, and provides good thermal conductivity to reduce temperature fluctuation.The braiding wire can with the heating and cooling dual mode apace with the waste gas heat-shift.As a result, the exhaust gas temperature peak value of fluctuation and transient state and valley flatten and equalization.This causes distributing to incinerating more favourable exhaust gas temperature, then can not provide incineration because peak temperature can cause incinerating low temperature out of control.Do not have at this paper under the situation of explanation in addition, thermostabiliser 104 will be understood that traditional thermostabiliser.

System 100 can comprise at least one cooling equipment, and this cooling equipment is selected from: be used for ambient air inject waste gas blower, be used for water is injected the pump of waste gas and the waste gas/ambient air heat exchanger by modulation air fan operation.Aspect this, blower 105 can be set cool exterior air is injected into the place ahead of diesel oil oxidation catalyst converter 107.Blower 105 can be with following manner control to incinerate and to operate effectively motor effectively.In brief, as required, gather circulation time at the needs coal smoke, blower 105 can be activated by electronic control module 106.As below describing, blower 105 can be controlled by electronic control module 106 according to the pressure of diesel particulate transducer 110 and the intake temperature of transducer 110.

Some diesel engine are characterised in that having high-temp waste gas distributes, and it can provide efficient, continue but incineration intermittently when diesel oxidation catalyst (DOC) coupling with high activity joins.For example, some oxidation catalyst can provide 25% NO to NO when 150 ℃ to 175 ℃ exhaust gas temperature ₂Transformation efficiency.This transformation efficiency can provide enough incinerations.When higher exhaust gas temperature, conversion ratio is higher and the incineration rate is higher.Excessive incineration can cause building up the reduction of efficient.Therefore, expectation provides the device of control incineration course to maintain under the optimum state with relevant back pressure to guarantee that coal smoke is built up efficient for the motor under operating in transient state and equilibrium condition.

As described, system 100 can comprise the feedback control system that is used to control exhaust gas temperature.Feedback control system can comprise based on the closed loop control logic that back pressure is maintained optimal level under given engine RPM and transducer inlet temperature.Aspect this, feedback control system can be controlled exhaust gas temperature based on the factor of the temperature in the pressure drop that comprises DPC, DPC the place ahead and engine RPM etc.Feedback control system can be operated with the monitoring exhaust gas temperature and in response to predetermined condition cooling is provided.The pressure drop that---for example the temperature in transducer the place ahead and engine RPM---measures down at given engine operating condition need convert to reference to pressure drop data.Thisly can be provided in the look-up table under specified temp and the engine RPM with reference to pressure drop data.For the purpose of assessing, the pressure drop of being calculated is compared with the equivalent pressure drop under the reference conditions.

Optimum translation device condition is to reduce efficient and reasonably pressure drop based on the coal smoke of the best, and it can be set up by shining upon.Several replacement schemes of waste gas cooling control also are acceptable.For example, for example injecting, cold fluid such as ambient air or water can be effective.Alternatively, waste gas/ambient air heat exchanger of operating by the modulation air fan that waste gas convection current cooling is provided also is effective.

ECU (electronic control unit) 106 can be used to introduce the blower 105 of cooling air in response to first signal operation with control.First signal can produce in response to predetermined pressure.By pressure transducer 109 this pressure of two-sided measurement at diesel particulate transducer 110.The diesel particulate transducer can be with above-mentioned similar.If back pressure is lower than goal pressure, then the diesel particulate transducer allows coal smoke to gather.This limits to incinerate by the startup refrigerating mode and realizes.On the other hand,, then allow to incinerate, reach the target back pressure up to back pressure by stopping refrigerating mode if back pressure is higher than goal pressure.The fluctuation up to 10% of actual back pressure and target back pressure allows.Like this, this control procedure is similar to the thermostatically control function.

The target control function suppresses/is restricted to minimum and realize by allow to incinerate taking place maybe will to incinerate.This realizes so that coal smoke gathers by waste gas is cooled to floor level.Alternatively, can increase exhaust gas temperature so that maximum incineration to be provided.A kind of effective, simple method is with blower 105 ambient air to be injected in the waste gas in DOC 107 the place aheads.Can modulate the air that injected to obtain maximum efficient.When using thermostabiliser, the response time of blower becomes more inessential, because the fluctuation of exhaust gas temperature is little.The amount of injecting air accounts for the sub-fraction of waste gas, for example usually less than 10%.

System 100 can comprise the security feature of the exhaust gas temperature that is used to measure DPC 110 the place aheads, all is no more than specific threshold value to guarantee the highest exhaust gas temperature under engine operating condition arbitrarily---this threshold value can cause not controlled incineration.Aspect this, monitor the temperature in transducer the place ahead, and it is compared with default temperature.Signal can produce in response to predetermined inlet temperature by the temperature transducer 108 that is positioned at DPC 110 inlets.When the exhaust gas temperature height and caused because of coal smoke when to incinerate the heat discharge be high, General might cause incineration that quicken or out of control (being equivalent to regeneration out of control).When this temperature conditions occurred, no matter the back pressure of transducer 110 how, always inject maximum air to reduce temperature by blower, the exhaust gas temperature up to transducer 110 the place aheads reached secure threshold.

In operation, can come the operational feedback control system so that effective incineration to be provided by the pressure drop of monitoring DPC, the temperature signal and the engine RPM in monitoring DPC the place ahead.Feedback control system can be calculated the concrete pressure drop and with itself and threshold data relatively under given engine operating condition.For example, threshold data can obtain from look-up table.Aspect this, when the concrete pressure drop of monitoring is lower than predetermined concrete pressure drop and when the temperature of monitoring is higher than predetermined temperature threshold, feedback control system can be operated with control waste gas refrigerating function.

In a plurality of examples, the utility model provides a kind of DPC, and it is a kind of passive equipment, does not have driving part, sensor and electronic unit near the engine exhaust system.The operation of whole system can be totally independent of power operation.This system can have sub-micron and nanoparticle and reaches 95 to 99% very high agglomeration efficient.Most of these agglomeration particulates are incinerated into nontoxic by product.As the situation of related domain similar devices, some particulates escape into tail pipe.For surpassing 10 microns for the PM10 standard, surpassing under 2.5 microns the situation for PM 2.5 standards, the size of this particulate is big, and does not constitute particle contamination in their size.As a result, transducer has two groups of particulates and reduces efficient, promptly measures efficient (based on total effusion particulate) and approval efficient (based on the PM10/PM2.5 standard).

System described here can comprise further that the waste gas fluid that will leave DPC is connected to exhaust gas recirculation (EGR) system and a valve of diesel engine, optionally waste gas is turned to egr system from DPC, wherein be injected into waste gas in the engine intake by low temperature refrigeration and removed the particulate of easily overflowing arbitrarily basically.Increase this system and be called low pressure EGR system.Compare with the high pressure egr system, this system provides extraordinary performance, because low pressure EGR system provides cleaning and low temperature refrigeration to gas, high-pressure system then can not realize these functions.Egr system can be substantially similar to U.S. Patent No. 7,266, the ERG system described in 943.In this mode by reference with U.S. Patent No. 7,266,943 full text be incorporated into herein.

Though in specification, described concrete example and shown in the drawings, can make multiple change but those skilled in the art should understand, and can use equivalent element to replace its element and do not deviate from the scope of the present utility model that is defined by the claims.In addition, can clearly expect the mixing and the cooperation of feature, element and/or function between each example at this, make those skilled in the art to recognize that feature, element and/or the function of an example can suitably be attached in another example, unless above additionally explanation by the utility model.In addition, can make many remodeling so that concrete situation or material are suitable for the utility model and do not deviate under the situation of essential scope of the present utility model.Therefore, the utility model not by shown in the accompanying drawing, specification is described, limit as the concrete example of the execution preferred forms of expecting at present of the present utility model, on the contrary, scope of the present utility model will comprise the description that drops on arbitrarily above or the mode of execution in the category of appended claim arbitrarily.

Claims

1. a diesel particulate transducer (DPC), it is used to collect and incinerate the particulate matter from diesel engine exhaust, and described DPC comprises:

Exhaust passageway, it extends through described DPC from diesel engine;

Housing; And

At least one crosses filter core, and it is arranged in described housing,

Described DPC is characterised in that also and comprises:

The electricity burner; And

Pulse power supply, it is connected to described electric burner to incinerate collected coal smoke.

2. DPC as claimed in claim 1 further comprises the diesel oil oxidation catalyst converter (DOC) that is arranged in described exhaust passageway.

3. DPC as claimed in claim 2, wherein said DOC with the low pressure loss that waste gas is provided, the high mixing and turbulent-flow conditions, thereby can apply a spot of precious metal by the wire gaze matrix structure of sintering.

4. DPC as claimed in claim 1, the wherein said filter core of crossing comprises at least one clad metal wire stratum reticulare radially, the thickness of described clad metal wire stratum reticulare is 15 millimeters to 25 millimeters, qualification cyclone agglomerator.

5. DPC as claimed in claim 1, wherein said electric burner comprise two stainless steel fine groove nets that radially hold described complex metal wire-mesh cyclone agglomerator.

6. DPC as claimed in claim 4, the wherein said filter core of crossing further comprises the blow-out net, and described blow-out net is made of the bigbore fine groove net of multilayer, and described multilayer fine groove net is set to the described upstream integral inner parts of crossing filter core.

7. DPC as claimed in claim 4, the wherein said filter core of crossing further comprises the oxidation catalyzer that is netted, it is as the described inner member after the blow-out net of being positioned at of crossing filter core.

8. DPC as claimed in claim 1, wherein said electric burner comprises:

Inboard heavy caliber fine groove net electrical ground;

Be connected to the small-bore fine groove net in the outside of pulse power supply;

The base metal catalysts net; And

Ceramic isolators, its between the net of described inboard net and the described outside so that 0.25 millimeter to 0.50 millimeter electrical insulation gap to be provided.

9. DPC as claimed in claim 8 further comprises power supply, is used to provide pulse electric energy by capturing the coal smoke in described burner gap to incinerate.

10. DPC as claimed in claim 8, wherein said base metal catalyst converter are selected from and twine one of wire and plain net.

11. DPC as claimed in claim 8, it is 70 microns or littler opening with as filter that wherein said outside net limits a plurality of diameters, thereby maintain the agglomeration soot particles that is the caking form, thereby and allow the pressure of excessive coal smoke to discharge the obstruction that prevents exhaust passageway.

12. DPC as claimed in claim 1, the pulse power supply of wherein said electric burner 12 volts to the scope of 48 volt direct currents, and apply with 100 hertz to 10,000 hertz frequency and 10% to 30% low duty ratio.

13. DPC as claimed in claim 1 further comprises thermostabiliser, described thermostabiliser is arranged in the exhaust passageway in described DOC the place ahead, is used for exhaust gas temperature dropped to being lower than 400 ℃ and increase NO ₂Incinerate the serviceability of mechanism; Described thermostabiliser is made of the sintered metal mesh matrix with high thermal conductivity, high thermal inertia and high-permeability.

14. DPC as claimed in claim 1, the gas recirculation system (EGR) that further comprises low pressure, the waste gas that described gas recirculation system will leave described DPC is connected to the suction port of described diesel engine by the valve fluid, optionally waste gas is turned to described motor from described DPC, wherein said EGR flows by low temperature refrigeration and has removed the pollutant of easily overflowing arbitrarily basically.

15. DPC as claimed in claim 1, the wherein said filter core of crossing comprises:

At least one radial layer, it limits the complex metal wire-mesh cyclone agglomerator; And

The electricity burner, it radially holds described wire gaze cyclone agglomerator.

16. DPC as claimed in claim 1 further comprises being set to the described blow-out net of crossing the integral inner parts of filter core.

17. DPC as claimed in claim 1 further comprises the oxidation catalyst net of crossing the integral inner parts of filter core as described.

18. DPC as claimed in claim 16, wherein said blow-out net is made of the fine groove net that multilayer has opening, the size of described opening is restricted to minimum in order to coal smoke is gathered, and is configured with crooked flow path to catch unburned fuel with cooling down high-temperature to prevent to filter the spontaneous combustion in the core.

19. DPC as claimed in claim 1, wherein said burner comprises:

Inboard grounded screen;

Outside net;

The base metal catalyst converter; And

Ceramic isolators, forming gap between the two, described gap is by collected coal smoke bridge joint conductively between the net of described inboard net and the described outside for it.

20. DPC as claimed in claim 19, wherein said ceramic isolators limits 0.25 millimeter to 0.5 millimeter fixed interval (FI).

21. DPC as claimed in claim 19, it is 70 microns or littler opening that wherein said outside net limits a plurality of diameters.

22. DPC as claimed in claim 1 further comprises passive control device, is used to monitor the resistance of described burner and in response to the described burner of predetermined threshold value resistive actuation.

23. DPC as claimed in claim 1, wherein said complex metal wire-mesh cyclone agglomerator and described outside net cooperate so that the thick bed of material with long residence time to be provided.

24. DPC as claimed in claim 1, comprise that further the waste gas fluid that will leave described particulate transducer is connected to the gas recirculation system (EGR) and the valve of described diesel engine, optionally waste gas is turned to described egr system from described particulate transducer, the waste gas that wherein is injected into engine intake is by low temperature refrigeration and removed the pollutant of easily overflowing arbitrarily basically.