CN108625933A - A kind of diesel particulate trap based on DOC and DPF - Google Patents

Abstract

The invention relates to a DOC and DPF-based diesel particle trap, which comprises an air intake assembly, a DOC assembly, a DPF assembly and an air outlet assembly connected in sequence, and the air intake assembly is connected to the air outlet of the engine through a pipeline , the exhaust gas emitted by the diesel engine is introduced into the trap, the exhaust gas with black smoke particles enters the DOC assembly from the intake assembly, and the DOC carrier in the DOC assembly removes the harmful gas in the exhaust gas, and is catalyzed by the DOC assembly The oxidized exhaust gas enters the DPF assembly, and the DPF ceramic carrier in the DPF assembly absorbs the soot particles, and the exhaust gas treated by the DPF assembly is discharged into the atmosphere through the outlet assembly. The invention can improve the internal catalytic oxidation reaction, prolong the use effect of the catcher, so that the emission of the vehicle can meet the requirements of the national standard for a long time.

Description

A Diesel Engine Particulate Filter Based on DOC and DPF

technical field

The invention relates to a particle trap, in particular to a diesel engine particle trap based on DOC and DPF. The utility model belongs to the technical field of energy-saving and environment-friendly machinery.

Background technique

The particle filter can reduce the soot produced by the diesel engine by more than 90%. The captured particulate emissions are then burned up during vehicle operation. Its working principle is as follows: if the diesel particulate filter is sprayed with metal platinum, rhodium, and palladium, the black smoke containing carbon particles discharged from the diesel engine enters the engine exhaust particulate filter through a special pipe, and passes through the densely arranged inside. The bag filter absorbs the soot particles on the filter made of metal fiber felt; when the adsorption amount of the particles reaches a certain level, the burner at the end automatically ignites and burns the soot particles adsorbed on it, into carbon dioxide that is harmless to the human body. To do this, the catcher employs advanced electronic control systems, catalytic coatings and fuel-added catalysts (FBC). Such fuel-added catalysts contain metals such as cerium, iron, and platinum. These materials are added in proportion to the fuel, and with the help of the engine control system, not only the amount of particulate matter is controlled, but also the emission of pollutants such as hydrocarbons and polluting gases. The regeneration or purge function of the trap must be done on a controlled basis to keep the trap from becoming clogged with soot. After the decontamination cycle is complete, any residual dust or filter residue will eventually be manually removed during routine maintenance.

The diesel engine exhaust aftertreatment device is mainly composed of an oxidation-catalyzed DOC ceramic filter element (catalytic honeycomb ceramic carrier) and a DPF ceramic filter element (catalytic particulate filter) coated with precious metals and molecular sieve adsorbents with unique properties.

The role of the DOC catalytic carrier is mainly to reduce carbon monoxide CO, hydrocarbon HC, and particulate matter PM through the catalytic oxidation reaction. The prepared catalyst carrier has a higher specific surface area and a larger pore volume; , CO, and soluble organic matter (SOF) have a low ignition temperature, high conversion efficiency, and can inhibit the formation of sulfate at the same time. However, the thermal insulation effect of the existing DOC assembly structure is not ideal, resulting in insufficient internal catalytic oxidation reaction. After a long period of exhaust gas discharge, a large amount of pollution will accumulate in the device, and finally it will be discharged into the air through the exhaust exhaust pipe, making the vehicle's Exhaust emissions cannot meet the requirements of national standards, and at the same time affect air quality.

Contents of the invention

The technical problem to be solved by the present invention is to provide a diesel particulate trap based on DOC and DPF in view of the above-mentioned prior art, which can improve the internal catalytic oxidation reaction, prolong the use effect of the trap, and make the emission of the vehicle reach the national level for a long time. standard requirements.

The technical scheme adopted by the present invention to solve the above-mentioned problems is: a kind of diesel engine particulate catcher based on DOC and CDPF, comprising the intake assembly, DOC assembly, DPF assembly and air outlet assembly connected in sequence, the intake assembly The exhaust gas from the diesel engine is connected to the air outlet of the engine through a pipeline, and the exhaust gas emitted by the diesel engine is introduced into the trap. The exhaust gas with black smoke particles enters the DOC assembly from the intake assembly, and the DOC carrier in the DOC assembly converts the exhaust gas into the DOC assembly. Harmful gas removal, the exhaust gas after the catalytic oxidation of the DOC assembly enters the DPF assembly, the DPF ceramic carrier in the DPF assembly absorbs the soot particles, and the exhaust gas treated by the DPF assembly is discharged into the atmosphere through the outlet assembly .

Preferably, the air intake assembly includes a muffler pipe and a cylinder sleeved on the muffler pipe, a support plate and an end cover are respectively provided at the front and rear ends of the cylinder body, and the muffler pipe and the end cover are connected by the support plate and the end cover. A muffler chamber is formed between the cylinders, and muffler holes are evenly distributed on the surface of the muffler pipe located in the muffler chamber, and evenly distributed air outlet holes are opened on the front support plate of the cylinder body, and the exhaust gas dispersed by the muffler pipe enters into the In the muffler chamber, it flows into the DOC assembly through the air outlet holes on the support plate.

Preferably, a temperature sensor base and a pressure sensor base communicated with the muffler chamber are provided on the surface of the barrel for installing a temperature sensor and a pressure sensor respectively to detect the pressure and temperature of the exhaust gas in the intake assembly.

Preferably, the total cross-sectional area of all the sound-absorbing holes is the same as the cross-sectional area of the air intake of the air-intake assembly, and the discharged exhaust gas passes through the uniformly distributed small holes on the sound-absorbing pipe to break up the airflow, thereby playing the role of sound-absorbing.

Preferably, the DOC assembly has a double-layer structure of inner and outer cylinders, including an outer cylinder and an inner cylinder, and the two ends of the inner cylinder are connected to the inner wall of the outer cylinder through a partition, and the outer cylinder and the inner cylinder A layer of high-temperature-resistant aluminum silicate ceramic fiber blanket is wrapped between the inner cylinders for heat preservation, and the outer cylinder is connected with the front-end air intake assembly and the rear-end DPF assembly, which is used to catalyze and oxidize the DOC carrier of harmful gases in the exhaust gas Distributed on the surface of the inner cylinder.

Preferably, the surface of the outer cylinder is respectively provided with a temperature difference threaded seat, a pressure differential threaded seat and a differential pressure assembly bracket for installing a temperature sensor, a pressure sensor and a pressure sensor assembly to detect the internal temperature of the DOC assembly. temperature and pressure.

Preferably, the DPF assembly includes a fixed cylinder and an inner mesh body arranged in the fixed cylinder, a liner is arranged between the fixed cylinder and the inner mesh body, CDPF as a noble metal and molecular sieve adsorbent with unique properties The ceramic carrier is coated on the inner mesh body.

Preferably, micropores with a porosity as high as 48% and a pore diameter of 8 μm are distributed on the pore wall of the DPF ceramic carrier.

Preferably, the air outlet assembly includes an outlet cylinder, one side of the outlet cylinder is connected to the DPF assembly, and the other side is provided with an end cap with a hole in the middle, an outlet pipe is inserted into the hole of the end cap, and is located in the outlet cylinder. A reinforcing plate is arranged between the end of the air outlet pipe in the body and the end cover.

Preferably, the hoop includes two symmetrical semicircular connecting pieces, the semicircular connecting pieces are concavely formed with grooves for accommodating flanges, and the two ends of the semicircular connecting pieces are respectively provided with straps , the connection and fixation are realized through bolts and nuts between the correspondingly set two laps.

Compared with the prior art, the present invention has the advantages of:

In the present invention, the front-stage doc catalyst carrier is made into a double-layer structure of inner and outer cylinders. The inner cylinder is used to fix the catalyst carrier, and the outer cylinder is used to connect with the front air intake component and the rear DPF component. A layer of high temperature resistant aluminum silicate ceramic fiber blanket is wrapped between the two cylinders for heat preservation. When the original machine exhaust gas passes through the doc catalyst carrier, the temperature of the original machine exhaust will react with the noble metal platinum in the doc, thereby increasing the reaction temperature. The role of the high-temperature-resistant aluminum silicate ceramic fiber blanket in the double-layer cylinder is to reduce the heat loss after the reaction and maintain the reaction temperature of the catalyst, so as to achieve a better catalytic effect.

Description of drawings

Fig. 1 is the schematic diagram of a kind of diesel particulate catcher based on DOC and DPF of the embodiment of the present invention;

Fig. 2 is the schematic diagram of the intake assembly of the embodiment of the present invention;

Fig. 3 is a perspective view of Fig. 2;

Fig. 4 is the schematic diagram of the DOC assembly of the embodiment of the present invention;

Figure 5 is a perspective view of Figure 4;

6 is a schematic diagram of a DPF assembly according to an embodiment of the present invention;

Fig. 7 is a schematic diagram of an air outlet assembly according to an embodiment of the present invention;

Fig. 8 is a schematic diagram of a hoop according to an embodiment of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Referring to Fig. 1, a diesel particulate filter based on DOC and DPF in this embodiment includes an intake assembly 1, a DOC assembly 2, a DPF assembly 3 and an air outlet assembly 4 connected in sequence, and each component The air intake assembly 1 is connected with the air outlet of the engine through a pipe, and the exhaust gas emitted by the diesel engine is introduced into and captured. The exhaust gas with black smoke particles enters the DOC assembly 2 from the intake assembly 1. The DOC assembly 2 is an oxidation-catalyzed DOC ceramic filter element (catalytic honeycomb ceramic carrier), mainly through catalytic oxidation reaction, Reduce carbon monoxide CO, hydrocarbon HC and particulate matter PM in the exhaust gas, the prepared catalyst carrier has a higher specific surface area and a larger pore size (16-22 microns); has good oxidation performance, and is effective for HC, CO, soluble organic matter (SOF) has a low light-off temperature, high conversion efficiency, and can inhibit the formation of sulfate at the same time. After the catalytic oxidation of the DOC assembly 2, the exhaust gas enters the DPF assembly 3. The DPF catalytic particle filter is coated with precious metals And DPF ceramic carrier with unique performance molecular sieve adsorbent. Micropores with a porosity of more than 48% and a diameter of about 8 μm are distributed on the pore wall, and their main function is to eliminate harmful components such as soot particles (PM) in the exhaust gas of the diesel engine. It is discharged into the atmosphere through the air outlet assembly 4.

Referring to Figures 2 and 3, the air intake assembly 1 includes a muffler pipe 1.1 and a cylinder 1.2 sleeved on the muffler pipe 1.1, and support plates 1.2.1 and end covers are respectively provided at the front and rear ends of the cylinder 1.2 1.2.2, through the support plate 1.2.1 and the end cover 1.2.2, a muffler cavity 1.3 is formed between the muffler tube 1.1 and the cylinder body 1.2, and muffler holes 1.1.1 are evenly distributed on the surface of the muffler tube 1.1 in the muffler cavity 1.3 , the total sectional area of all silencing holes 1.1.1 is the same as the sectional area of the air inlet of the air intake assembly 1, and the exhaust gas that is discharged into is broken up by the evenly distributed small holes on the silencing pipe, thereby playing the role of silencing. On the front support plate 1.2.1 of the cylinder body 1.2, evenly distributed air outlet holes are opened, and the exhaust gas dispersed by the muffler tube enters the muffler cavity 1.3, and flows into the DOC main assembly through the air outlet holes on the support plate 1.2.1. In step 2, a flange is provided at the front end of the intake assembly 1 to facilitate the connection of the hoop 5 . At the same time, a temperature sensor base 1.4 and a pressure sensor base 1.5 communicated with the muffler chamber 1.3 are provided on the surface of the cylinder 1.2, which are respectively used for installing a temperature sensor and a pressure sensor to detect the pressure and pressure of the exhaust gas in the intake assembly. temperature.

Referring to Figures 4 and 5, the DOC assembly 2 is a double-layer structure of inner and outer cylinders, including an outer cylinder 2.1 and an inner cylinder 2.2. Wall connection, a layer of high temperature resistant aluminum silicate ceramic fiber blanket 2.4 is wrapped between the outer cylinder 2.1 and the inner cylinder 2.2 for heat preservation, wherein the two ends of the outer cylinder 2.1 are respectively provided with flanges, through which The hoop 5 is connected to the front air intake assembly 1 and the rear DPF assembly 3, and a DOC carrier 2.5 is distributed on the surface of the inner cylinder 2.2. When the exhaust gas from the engine passes through the DOC assembly 2, the exhaust gas will React with the DOC carrier under temperature conditions to increase the reaction temperature, and the high-temperature resistant aluminum silicate ceramic fiber blanket 2.4 in the double-layer cylinder can reduce the heat loss after the reaction and maintain the reaction temperature of the catalyst to achieve better catalytic effect. At the same time, the surface of the outer cylinder 2.1 is respectively provided with a temperature difference threaded seat 2.1.1, a pressure difference threaded seat 2.1.2 and a pressure difference assembly bracket 2.1.3 for installing temperature sensors, pressure sensors and pressure sensors assembly to detect the temperature and pressure inside the DOC assembly.

Referring to Fig. 6, the DPF assembly 3 includes a fixed cylinder 3.1 and an inner mesh body 3.2 arranged in the fixed cylinder 3.1, and a gasket 3.3 is arranged between the fixed cylinder 3.1 and the inner mesh body 3.2, as The DPF ceramic carrier of precious metal and molecular sieve adsorbent with unique performance is coated on the inner network body 3.2, and the pore wall of the DPF ceramic carrier is distributed with micropores with a porosity of more than 48% and a pore diameter of about 8 μm, which is used to eliminate diesel engine exhaust Harmful components such as soot particulate matter (PM) in the air. The two ends of the internal mesh body 3.2 are fixedly connected with the fixed cylinder 3.1 through the retaining ring 3.4, and the two ends of the fixed cylinder 3.1 are respectively connected with the DOC assembly 2 and the air outlet assembly 4 through setting flanges.

Referring to Fig. 7, the air outlet assembly 4 includes an air outlet cylinder body 4.1, one side of the air outlet cylinder body 4.1 is connected to the DPF assembly 3 by setting a flange, and the other side is provided with an end cover 4.2 with a hole in the middle, on the end cover An outlet pipe 4.3 is inserted into the hole of 4.2, and a reinforcing plate 4.4 is provided between the end of the outlet pipe 4.3 in the outlet cylinder body 4.1 and the end cover 4.2 to fix the outlet pipe. The exhaust gas processed by the DPF assembly 3 passes through the outlet The outlet pipe of the assembly 4 is discharged into the atmosphere, thereby completing the entire exhaust gas discharge treatment process.

Referring to Fig. 8, the hoop 5 includes two symmetrical semicircular connectors 5.1, the semicircular connectors 5.1 are concavely formed with grooves for accommodating flanges, and at both ends of the semicircular connectors 5.1 There are respectively provided with a support 5.2, and the two correspondingly provided support 5.2 are connected and fixed by bolts and nuts.

In addition to the above-mentioned embodiments, the present invention also includes other implementations, and any technical solution formed by equivalent transformation or equivalent replacement shall fall within the protection scope of the claims of the present invention.

Claims (10)

1. A diesel particulate trap based on DOC and DPF, characterized in that: it comprises an air intake assembly, a DOC assembly, a DPF assembly and an air outlet assembly connected in sequence, and the air intake assembly passes through the pipeline and the engine. The gas outlet is connected, and the exhaust gas emitted by the diesel engine is introduced into the trap. The exhaust gas with black smoke particles enters the DOC assembly from the intake assembly. The DOC carrier in the DOC assembly removes the harmful gas in the exhaust gas, and passes through the DOC. The exhaust gas after the catalytic oxidation of the assembly enters the DPF assembly, and the DPF ceramic carrier in the DPF assembly absorbs the soot particles, and the exhaust gas treated by the DPF assembly is discharged into the atmosphere through the outlet assembly. 2. A diesel particulate filter based on DOC and DPF according to claim 1, characterized in that: the air intake assembly includes a muffler pipe and a cylinder sleeved on the muffler pipe, and the cylinder body The front and rear ends of the cylinder are respectively provided with a support plate and an end cover, through which a muffler cavity is formed between the muffler tube and the cylinder body, and muffler holes are evenly distributed on the surface of the muffler tube located in the muffler cavity, in the cylinder body There are evenly distributed air outlets on the front support plate, and the exhaust gas dispersed by the muffler tube enters the muffler chamber and flows into the DOC assembly through the air outlets on the support plate. 3. A kind of diesel particulate trap based on DOC and DPF according to claim 2, characterized in that: the surface of the cylinder is provided with a temperature sensor base and a pressure sensor base communicated with the muffler chamber, respectively for Install a temperature sensor and a pressure sensor to detect the pressure and temperature of the exhaust gas in the intake assembly. 4. A kind of diesel particulate catcher based on DOC and DPF according to claim 2, characterized in that: the total cross-sectional area of all sound-absorbing holes is the same as the air intake cross-sectional area of the air intake assembly, and the exhaust gas discharged into Through the uniformly distributed small holes on the muffler pipe, the airflow is broken up, so as to play the role of muffler. 5. A diesel particulate filter based on DOC and DPF according to claim 1, characterized in that: the DOC assembly is a double-layer structure of inner and outer cylinders, including an outer cylinder and an inner cylinder, and the inner cylinder The two ends of the outer cylinder are connected to the inner wall of the outer cylinder through a partition, and a layer of high-temperature-resistant aluminum silicate ceramic fiber blanket for heat preservation is wrapped between the outer cylinder and the inner cylinder, wherein the outer cylinder and the front end The gas assembly is connected to the back-end DPF assembly, and the DOC carrier used to catalyze and oxidize harmful gases in the exhaust gas is distributed on the surface of the inner cylinder. 6. A diesel particle trap based on DOC and DPF according to claim 5, characterized in that: a temperature difference threaded seat, a differential pressure threaded seat and a differential pressure assembly bracket are respectively provided on the surface of the outer cylinder , used to install the temperature sensor, pressure sensor and pressure sensor assembly to detect the temperature and pressure inside the DOC assembly. 7. A diesel particulate filter based on DOC and DPF according to claim 1, characterized in that: the DPF assembly includes a fixed cylinder and an inner mesh body arranged in the fixed cylinder, and in the fixed cylinder There is a liner between the body and the inner mesh body, and the DPF ceramic carrier as a precious metal and molecular sieve adsorbent with unique properties is coated on the inner mesh body. 8 . A diesel particulate filter based on DOC and DPF according to claim 7 , wherein micropores with a porosity as high as 48% and a diameter of 8 μm are distributed on the pore wall of the DPF ceramic carrier. 9. A diesel particulate filter based on DOC and DPF according to claim 1, characterized in that: the air outlet assembly includes an air outlet cylinder, one side of the outlet cylinder is connected with the DPF assembly, and the other side is provided with The end cap with a hole in the middle is inserted with an air outlet pipe in the hole of the end cap, and a reinforcing plate is arranged between the end of the air outlet pipe in the air outlet cylinder body and the end cap. 10. A diesel particulate filter based on DOC and DPF according to claim 1, characterized in that: the hoop includes two symmetrical semicircular connecting pieces, and the semicircular connecting pieces are concavely formed to allow The groove of the flange is accommodated, and the two ends of the semicircular connecting piece are respectively provided with straps, and the two corresponding straps are connected and fixed by bolts and nuts.