阅读说明：本技术 一种后处理两级尿素喷射系统 (Aftertreatment two-stage urea injection system ) 是由 刘洪岐 朱万冬 江增辉 李明星 于 2021-01-29 设计创作，主要内容包括：本申请实施例公开了一种后处理两级尿素喷射系统,用于提高NOx的反应效率,使得NOx在得到充分反应的情况下向外排出,减少对环境造成的污染。本申请包括：氧化催化器通过第一通气管与集成式氮氧颗粒捕集器连接,第一通气管与一级尿素喷嘴连通,第一NOx传感器安装在第一通气管上,集成式氮氧颗粒捕集器通过第二通气管与尾气后处理系统连接,第二通气管与二级尿素喷嘴连通,第二NOx传感器安装在第二通气管上,尿素喷射控制系统根据第一通气管内部的NOx浓度控制一级尿素喷嘴中尿素的喷射量,尿素喷射控制系统根据第二通气管内部的NOx浓度以及第二通气管内部的储氨量控制二级喷嘴中尿素的喷射量。(The embodiment of the application discloses post-treatment two-stage urea injection system for improving the reaction efficiency of NOx, enabling the NOx to be discharged outwards under the condition of sufficient reaction, and reducing pollution to the environment. The application includes: the oxidation catalyst is connected with the integrated nitrogen-oxygen particle trap through a first vent pipe, the first vent pipe is communicated with a first-stage urea nozzle, a first NOx sensor is installed on the first vent pipe, the integrated nitrogen-oxygen particle trap is connected with a tail gas aftertreatment system through a second vent pipe, the second vent pipe is communicated with a second-stage urea nozzle, a second NOx sensor is installed on the second vent pipe, a urea injection control system controls the injection amount of urea in the first-stage urea nozzle according to the NOx concentration inside the first vent pipe, and the urea injection control system controls the injection amount of urea in the second-stage urea nozzle according to the NOx concentration inside the second vent pipe and the ammonia storage amount inside the second vent pipe.)

1. An aftertreatment two-stage urea injection system, comprising: the device comprises an oxidation catalyst, a primary urea nozzle, a secondary urea nozzle, an exhaust aftertreatment system, an integrated nitrogen-oxygen particle trap, a first NOx sensor, a second NOx sensor and a urea injection control system;

the oxidation catalyst is connected with the integrated nitrogen-oxygen particle trap through a first vent pipe, the first vent pipe is communicated with the first-stage urea nozzle, the first NOx sensor is installed on the first vent pipe and used for detecting the NOx concentration inside the first vent pipe, the integrated nitrogen-oxygen particle trap is connected with the tail gas aftertreatment system through a second vent pipe, the second vent pipe is communicated with the second-stage urea nozzle, the second NOx sensor is installed on the second vent pipe and used for detecting the NOx concentration inside the second vent pipe, the urea injection control system is respectively connected with the first-stage urea nozzle and the second-stage urea nozzle and controls the injection amount of urea in the first-stage urea nozzle according to the NOx concentration inside the first vent pipe, the urea injection control system controls the injection amount of urea in the secondary nozzle according to the concentration of NOx in the second vent pipe and the ammonia storage amount in the second vent pipe, the integrated nitrogen-oxygen particle trap is used for trapping particles in exhaust gas discharged by the first vent pipe and reacting with the NOx, and the tail gas aftertreatment system is used for reacting with the NOx in the second vent pipe.

2. The aftertreatment two-stage urea injection system of claim 1, wherein the urea storage tank is provided with a first port and a second port, the first port is connected with a first through pipe, the first through pipe is connected with the first-stage urea nozzle, the second port is connected with a second through pipe, and the second through pipe is connected with the second-stage urea nozzle.

3. The aftertreatment two-stage urea injection system of claim 2, wherein a urea concentration detector is installed inside the urea storage tank and connected with the urea control injection control system, and the urea concentration detector is used for detecting the urea concentration inside the urea storage tank.

4. The aftertreatment two-stage urea injection system according to claim 1, wherein an ammonia gas detector is installed inside the second vent pipe, the ammonia gas detector is connected with the urea injection control system, and the ammonia gas detector is used for detecting the amount of ammonia gas inside the second vent pipe and sending data of the detected amount of ammonia gas to the urea injection control system.

5. The aftertreatment two-stage urea injection system of claim 1, wherein the first vent line has a first temperature sensor mounted thereon, and the second vent line has a second temperature sensor mounted thereon, the first temperature sensor being configured to sense a temperature on the first vent line, the second temperature sensor being configured to sense a temperature on the second vent line.

6. The aftertreatment two-stage urea injection system according to claim 1, wherein a gas flow rate detector is mounted inside the second vent pipe and connected with the urea injection control system, and the gas flow rate detector is used for detecting the exhaust gas flow rate inside the second vent pipe and sending information of the detected gas flow rate to the urea injection control system.

7. The aftertreatment two-stage urea injection system according to any one of claims 4-6, wherein the urea injection control system is connected to the first temperature detector and the second temperature detector, respectively, and is configured to control the injection amount of the two-stage urea nozzle based on the ammonia storage amount in the second vent pipe, the detected NOx concentration in the second vent pipe by the second NOx sensor, and the detected temperature by the second temperature detector.

8. The aftertreatment two-stage urea injection system of claim 1, wherein the integrated NOx particulate trap includes a particulate trap, a barrier layer mesh mounted on the particulate trap, and a coating layer plate for trapping particulate matter in the exhaust gas, wherein the coating layer plate has a plurality of orifices disposed thereon, the coating layer plate is connected to the barrier layer mesh, and the coating layer plate is coated with a catalyst for reacting with NOx in the exhaust gas.

9. The aftertreatment two-stage urea injection system of claim 2, wherein a sealing rubber ring is disposed at a junction of the urea storage tank and the primary urea nozzle, and a sealing rubber ring is disposed at a junction of the urea nozzle and the secondary urea nozzle.

10. The aftertreatment two-stage urea injection system according to claim 1, wherein an air-tight glue is applied to the joint of the second vent pipe and the exhaust aftertreatment system, and the air-tight glue is used for preventing NOx or ammonia gas in the second vent pipe from leaking outwards.

Technical Field

The embodiment of the application relates to the technical field of diesel oil aftertreatment, in particular to an aftertreatment two-stage urea injection system.

Background

The main effect of automobile aftertreatment system among the prior art is to eliminate NOx in the automobile exhaust waste gas as far as possible, theory of operation is when automobile exhaust's waste gas enters into the blast pipe, the urea nozzle of installing on the blast pipe can be toward the inside urea that sprays of blast pipe, the urea that sprays and enter into the inside blast pipe can hydrolyze under the effect of high temperature and generate the ammonia, the ammonia can react with the oxynitrides in the waste gas, reduction reaction generates nitrogen gas, outwards discharge, can the effectual pollution of reduction automobile exhaust waste gas to the environment.

Aiming at the existing exhaust gas post-treatment device, in the existing post-treatment system, the mode of integrated nitrogen-oxygen particle trap + SCR (Selective Catalytic Reduction) is common, under the integrated nitrogen-oxygen particle trap + SCR mode, the adopted urea injection system usually adopts a single-nozzle injection control mode, and has the following defects that under the single-injection mode, only ammonia gas injection treatment can be carried out on the integrated nitrogen-oxygen particle trap in the first stage, but the whole system has two-stage treatment process on NOx, if the reaction of the integrated nitrogen-oxygen particle trap in the first stage on NOx is not complete, the part of NOx which is not reacted can enter the second stage SCR for reaction, but under the single-injection control mode, when the ammonia storage is required to be adjusted in time in the second stage SCR, the quick realization can not be realized, under the condition that the ammonia storage amount in the second stage SCR is not enough, the insufficient reaction efficiency of the NOx is easily caused, so that the NOx is discharged outwards under the condition of not obtaining sufficient reaction, and the pollution to the environment is caused.

Disclosure of Invention

The embodiment of the application provides an aftertreatment two-stage urea injection system, which can improve the reaction efficiency of NOx, enables the NOx to be discharged outwards under the condition of sufficient reaction, and reduces the pollution to the environment.

The application provides an aftertreatment two-stage urea injection system, includes: the device comprises an oxidation catalyst, a primary urea nozzle, a secondary urea nozzle, an exhaust aftertreatment system, an integrated nitrogen-oxygen particle trap, a first NOx sensor, a second NOx sensor and a urea injection control system;

the oxidation catalyst is connected with the integrated nitrogen-oxygen particle trap through a first vent pipe, the first vent pipe is communicated with the first-stage urea nozzle, the first NOx sensor is installed on the first vent pipe and used for detecting the NOx concentration inside the first vent pipe, the integrated nitrogen-oxygen particle trap is connected with the tail gas aftertreatment system through a second vent pipe, the second vent pipe is communicated with the second-stage urea nozzle, the second NOx sensor is installed on the second vent pipe and used for detecting the NOx concentration inside the second vent pipe, the urea injection control system is respectively connected with the first-stage urea nozzle and the second-stage urea nozzle and controls the injection amount of urea in the first-stage urea nozzle according to the NOx concentration inside the first vent pipe, the urea injection control system controls the injection amount of urea in the secondary nozzle according to the concentration of NOx in the second vent pipe and the ammonia storage amount in the second vent pipe, the integrated nitrogen-oxygen particle trap is used for trapping particles in exhaust gas discharged by the first vent pipe and reacting with the NOx, and the tail gas aftertreatment system is used for reacting with the NOx in the second vent pipe.

Optionally, be provided with first opening and second opening on the urea storage tank, be connected with first siphunculus on the first opening, first siphunculus with one-level urea nozzle connects, be connected with the second siphunculus on the second opening, the second siphunculus with second grade urea nozzle connects.

Optionally, urea storage tank internally mounted has urea concentration detector, urea concentration detector with urea control sprays control system and connects, urea concentration detector is used for detecting the inside urea concentration of urea storage tank.

Optionally, an ammonia gas detector is installed inside the second vent pipe, the ammonia gas detector is connected with the urea injection control system, and the ammonia gas detector is used for detecting the amount of ammonia gas inside the second vent pipe and sending data of the detected amount of ammonia gas to the urea injection control system.

Optionally, a first temperature detector is installed on the first vent pipe, a second temperature detector is installed on the second vent pipe, the first temperature detector is used for detecting the temperature on the first vent pipe, and the second temperature detector is used for detecting the temperature on the second vent pipe.

Optionally, a gas flow velocity detector is installed inside the second vent pipe, the gas flow velocity detector is connected to the urea injection control system, and the gas flow velocity detector is configured to detect a flow velocity of exhaust gas inside the second vent pipe, and send information of the detected gas flow velocity to the urea injection control system.

Optionally, the urea injection control system is connected to the first temperature detector and the second temperature detector, respectively, and is configured to control the injection amount of the secondary urea nozzle according to the ammonia storage amount in the second vent pipe, the detected NOx concentration in the second vent pipe by the second NOx sensor, and the detected temperature by the second temperature detector.

Optionally, integrated form nitrogen oxygen particle trap includes particle trap, separation layer net and paints the plywood, separation layer net is installed on the particle trap, the particle trap is arranged in the particulate matter of entrapment waste gas, it is provided with a plurality of drill way to paint on the plywood, paint the plywood with separation layer net is connected, paint and scribble the catalyst that is arranged in reacting with NOx in the waste gas on the plywood.

Optionally, a sealing rubber ring is arranged at the joint of the urea storage tank and the first-stage urea nozzle, and a sealing rubber ring is arranged at the joint of the urea nozzle and the second-stage urea nozzle.

Optionally, an air-tight glue is coated at the joint of the second vent pipe and the tail gas aftertreatment system, and the air-tight glue is used for preventing the NOx or ammonia gas in the second vent pipe from leaking outwards.

According to the technical scheme, the embodiment of the application has the following advantages:

the device is provided with a primary urea nozzle, a secondary urea nozzle, an exhaust aftertreatment system, an integrated nitrogen-oxygen particle trap and a urea injection control system; the oxidation catalyst is connected with the integrated nitrogen-oxygen particle catcher through a first vent pipe, the first vent pipe is communicated with the first-stage urea nozzle, the integrated nitrogen-oxygen particle catcher is connected with the tail gas aftertreatment system through a second vent pipe, the second vent pipe is communicated with the second-stage urea nozzle, and the urea injection control system is respectively connected with the first-stage urea nozzle and the second-stage urea nozzle; according to the method, the first-stage urea nozzle and the second-stage urea nozzle are arranged, when the NOx in the first vent pipe does not completely react with the ammonia gas, the NOx is treated by the integrated nitrogen-oxygen particle trap and then enters the second vent pipe, if the concentration content of the NOx in the second vent pipe is detected, the urea injection control system controls the injection quantity of the second-stage urea nozzle, the reaction efficiency of the NOx can be improved through the second-stage injection treatment, the NOx is discharged outwards under the condition of sufficient reaction, and the pollution to the environment is reduced.

Drawings

FIG. 1 is a schematic illustration of a two-stage urea injection system for aftertreatment according to the present application;

FIG. 2 is a schematic diagram of the connection of a urea injection control system in a two-stage urea injection system for aftertreatment according to the subject application;

FIG. 3 is a schematic view of the interior of an integrated NOx particulate trap for use in an aftertreatment two-stage urea injection system according to the present application.

Detailed Description

In the existing after-treatment system, the mode of the integrated nitrogen-oxygen particle trap and SCR is common, in the integrated nitrogen-oxygen particle catcher and SCR mode, the adopted urea injection system usually adopts a single-nozzle injection control mode, and has the following defects that in the single-nozzle injection mode, only the SDPF in the first stage can be subjected to ammonia injection treatment, however, the whole system has a two-stage treatment process for the NOx, if the reaction of the integrated nitrogen-oxygen particle trap in the first stage to the NOx is not complete, the unreacted part of the NOx will enter the second stage SCR to react, but in the single injection control mode, when the ammonia storage is required to be adjusted in time in the second-stage SCR, the ammonia storage cannot be quickly realized, and the insufficient reaction efficiency of NOx is easily caused under the condition that the ammonia storage amount in the second-stage SCR is insufficient, so that NOx is discharged to the outside without being sufficiently reacted, and causes pollution to the environment.

Based on this, the application provides a post-treatment two-stage urea injection system, can improve NOx's reaction efficiency for NOx obtains outwards discharging under the circumstances that fully reacts, reduces the pollution that causes the environment.

Referring to fig. 1-3, the present application provides an aftertreatment two-stage urea injection system comprising: the system comprises an oxidation catalyst 1, a primary urea nozzle 3, a secondary urea nozzle 6, an exhaust gas aftertreatment system 8, an integrated nitrogen-oxygen particle trap 5, a first NOx sensor 22, a second NOx sensor 72 and a urea injection control system 9; oxidation catalyst converter 1 through first breather pipe 2 with integrated form nitrogen oxygen particle trap 5 is connected, first breather pipe 2 with one-level urea nozzle 3 intercommunication, first NOx sensor 22 is installed on first breather pipe 2, first NOx sensor 22 is used for detecting the inside NOx concentration of first breather pipe 2, integrated form nitrogen oxygen particle trap 5 through second breather pipe 7 with tail gas aftertreatment system 8 is connected, second breather pipe 7 with second grade urea nozzle 6 intercommunication, second NOx sensor 72 is installed on second breather pipe 7, second NOx sensor 72 is used for detecting the inside NOx concentration of second breather pipe 7, urea injection control system 9 respectively with one-level urea nozzle 3 and second grade urea nozzle 6 are connected, urea injection control system 9 is according to the inside NOx concentration control of first breather pipe 2 urea injection in one-level urea nozzle 3 The urea injection control system 9 controls the injection amount of urea in the secondary nozzle according to the concentration of NOx in the second vent pipe 7 and the ammonia storage amount in the second vent pipe 7, the integrated nitrogen-oxygen particle trap 5 is used for trapping particles in exhaust gas discharged from the first vent pipe 2 and reacting with NOx, and the exhaust gas aftertreatment system 8 is used for reacting with NOx in the second vent pipe 7.

In the embodiment of the present application, the first-stage urea nozzle 3 is disposed on the first vent pipe 2, the second-stage urea nozzle 6 is disposed on the second vent pipe 7, and a predetermined distance is disposed between the first-stage urea nozzle 3 and the second-stage urea nozzle 6, in the present application, the distance between the first-stage urea nozzle 3 and the second-stage urea nozzle 6 is not specifically limited, and the integrated type nitrogen-oxygen particle trap 5 is installed between the first vent pipe 2 and the second vent pipe 7, wherein the integrated type nitrogen-oxygen particle trap 5 is formed by coating an SCR on an outlet channel of a DPF (Diesel particle trap), and a normal DPF is used for trapping particles, and after the SCR coating is applied on the outlet channel, the carrier of the integrated type nitrogen-oxygen particle trap 5 also has a function of converting NOx, and the discharged exhaust gas can trap and collect Particulate matter in the exhaust gas when passing through the integrated type nitrogen-oxygen particle trap 5, and can carry on the reaction to remove and process NOx in the exhaust gas; in practical application, exhaust gas discharged from an engine enters the oxidation catalyst 1 from an exhaust gas inlet, the exhaust gas enters the oxidation catalyst 1, carbon monoxide (CO) and Hydrocarbons (HC) in the exhaust gas can be converted into harmless water (H20) and carbon dioxide (CO2), the exhaust gas after reaction in the oxidation catalyst 1 enters the first breather pipe 2, a first NOx sensor 22 mounted on the first breather pipe 2 detects the NOx concentration in the exhaust gas and sends the detected concentration to the urea injection control system 9, and the urea injection control system 9 controls the primary urea nozzle 3 to inject a fixed amount of urea into the first breather pipe 2.

The exhaust gas discharged by the engine has a high temperature, the urea in the first breather pipe 2 can be divided into ammonia gas, the ammonia gas generated by decomposition is mainly used for reacting with NOx in the exhaust gas, and the exhaust gas of the engine is continuously discharged outwards, so that the NOx and the ammonia gas in the first breather pipe 2 cannot fully react, part of unreacted NOx can enter the integrated nitrogen-oxygen particle trap 5, the ammonia gas remained in the first breather pipe 2 can continuously react with the NOx in the first breather pipe 2, and it needs to be noted that the first-stage urea nozzle 3 still continuously sprays urea outwards at this time; when the ammonia gas enters the integrated nitrogen-oxygen particle trap 5, particulate matters in the exhaust gas are trapped firstly, then the exhaust gas passes through the SCR coating on the integrated nitrogen-oxygen particle trap 5, NOx in the exhaust gas is subjected to secondary reaction treatment, the exhaust gas after passing through the integrated nitrogen-oxygen particle trap 5 enters the second vent pipe 7, the second NOx sensor 72 arranged on the second vent pipe 7 detects the concentration of NOx in the second vent pipe 7 and sends the information of the concentration of NOx in the second vent pipe 7 to the urea injection control system 9, it needs to be noted that ammonia gas leaked from the first vent pipe 2 before exists in the second vent pipe 7, and when the secondary urea nozzle 6 injects urea into the second vent pipe 7, the amount of the ammonia gas leaked before calculation needs to be combined, so that the amount of the urea and the amount of the ammonia gas injected from the secondary urea nozzle 6 can fully react with the NOx in the second vent pipe 7, in the dual urea injection system, the ammonia storage amounts in the first-stage and second-stage injection systems have a certain control relationship, and in the treatment of NOx in the exhaust gas, two-stage injection treatment is required, wherein the two-stage injection treatment is respectively performed by urea injection control based on different ammonia storage requirements (based on a required amount capable of reducing nitrogen oxides in the exhaust gas and an ammonia storage amount capable of ensuring a reaction rate), and the first-stage urea injection requirement is derived from the sum of the deviation of an SCR ammonia storage target and an actual ammonia storage amount and the urea reaction consumption amount calculated based on a first NOx sensor; the target ammonia storage setting of the integrated NOx particulate trap 5 is based on the SCR bed temperature and the exhaust flow rate, and the ammonia storage requirement of the integrated NOx particulate trap 5 is based on the conversion efficiency requirement, the carrier bed temperature and the airspeed, given the ammonia storage requirement, combined with the deviation of the target ammonia storage from the current ammonia storage requirement and the NOx value identified by the second NOx sensor 72 to calculate the urea injection amount requirement, while accounting for the subtraction of the amount of ammonia that is identified as leaking based on the first NOx sensor 22.

When the integrated nitrogen-oxygen particle trap 5 is in regeneration, the first-stage urea injection is required to be closed, the method is only suitable for the second-stage urea injection, and the urea injection is required to be carried out according to the actual ammonia storage control requirement; in the embodiment of the application, the urea injection of the first stage and the urea injection of the second stage are relatively independent, the first stage can also establish an ammonia leakage model to calculate ammonia leaked into the second stage under different conditions, the ammonia supplement of the second stage can be increased on the basis, and meanwhile, the urea injection control of the second stage is required to realize that ammonia leakage cannot occur.

Optionally, a first port and a second port are arranged on the urea storage tank 4, the first port is connected with a first through pipe, the first through pipe is connected with the first-stage urea nozzle 3, the second port is connected with a second through pipe, and the second through pipe is connected with the second-stage urea nozzle 6; urea storage tank 4 internally mounted has urea concentration detector 41, urea concentration detector 41 with urea control sprays control system and connects, urea concentration detector 41 is used for detecting the inside urea concentration of urea storage tank 4.

In this embodiment, the first-stage urea nozzle 3 and the second-stage urea nozzle 6 are connected to a urea storage tank 4, in a normal state, both the first-stage urea nozzle 3 and the second-stage urea nozzle 6 are in a closed state, when urea needs to be injected into the first vent pipe 2, the urea control injection control system controls the first-stage urea nozzle 3 to be opened, the urea is used for injecting urea into the first vent pipe 2, when urea needs to be injected into the second vent pipe 7, the urea control injection system controls the second-stage urea nozzle 6 to be opened, the urea is used for injecting urea into the second vent pipe 7, it should be noted that the sealing glue is applied to the joints between the first-stage urea nozzle 3 and the second-stage urea nozzle 6 and the urea storage tank 4, and the sealing glue is mainly used for preventing urea in the urea storage tank 4 from leaking outwards and polluting the environment.

Optionally, an ammonia gas detector 73 is installed inside the second vent pipe 7, the ammonia gas detector 73 is connected to the urea injection control system, and the ammonia gas detector 73 is configured to detect the amount of ammonia gas inside the second vent pipe 7 and send data of the detected amount of ammonia gas to the urea injection control system 9.

In the embodiment of the present application, the ammonia gas detector 73 inside the second vent pipe 7 is mainly used for detecting ammonia gas leaked from the first vent pipe 2 into the second vent pipe 7, the injection amount of the urea nozzle in the second stage needs to be injected based on the ammonia gas storage amount in the second vent pipe 7, when the ammonia gas detector 73 detects ammonia gas leaked into the second vent pipe 7, the detected ammonia gas amount needs to be sent to the urea injection control system 9, the urea injection control system 9 controls the injection of the second stage urea nozzle 6 according to the NOx amount inside the second vent pipe 7 and the ammonia gas amount inside the second vent pipe 7, the urea injected into the second vent pipe 7 is decomposed into ammonia gas at high temperature of the exhaust gas, the decomposed ammonia gas and the ammonia gas leaked from the first vent pipe 2 act together to fully react with NOx in the exhaust gas in the second vent pipe 7, the amount of NOx discharged outwards is reduced to the minimum, and the pollution to the environment is reduced.

Optionally, a first temperature detector 21 is installed on the first vent pipe 2, a second temperature detector 71 is installed on the second vent pipe 7, the first temperature detector 21 is used for detecting the temperature on the first vent pipe 2, and the second temperature detector 71 is used for detecting the temperature on the second vent pipe 7.

In the embodiment of the present application, the first flue 2 is provided with the first temperature detector 21 for mainly detecting whether the temperature inside the first flue 2 can reach the decomposition temperature of urea, and urea can be decomposed into ammonia gas only when the temperature inside the first flue 2 reaches the decomposition temperature of urea, and the ammonia gas reacts with NOx in the exhaust gas sufficiently to become harmless gas N₂And water (H)₂O), similarly, a second temperature detector 71 is also installed on the second vent pipe 7, and is mainly used for detecting whether the temperature in the second vent pipe 7 can reach the decomposition temperature of urea, similar to the function of the first temperature detector 21, and will not be described herein again

Optionally, a gas flow rate detector 74 is installed inside the second vent pipe 7, the gas flow rate detector 74 is connected to the urea injection control system 9, and the gas flow rate detector 74 is configured to detect a flow rate of exhaust gas inside the second vent pipe 7 and send information of the detected gas flow rate to the urea injection control system 9; the urea injection control system 9 is connected to the first temperature detector 21 and the second temperature detector 71, respectively, and the urea injection control system 9 is configured to control the injection amount of the secondary urea nozzle 6 based on the ammonia storage amount in the second vent pipe 7, the NOx concentration detected in the second vent pipe 7 by the second NOx sensor 72, and the temperature detected by the second temperature detector 71.

Optionally, the integrated nitrogen-oxygen particle trap 5 includes a particle trap, a barrier layer net 51 and a coating layer plate 52, the barrier layer net 51 is installed on the particle trap, the particle trap is used for trapping particulate matters in the exhaust gas, the coating layer plate 52 is provided with a plurality of orifices, the coating layer plate 52 is connected with the barrier layer net 51, and a catalyst used for reacting with NOx in the exhaust gas is coated on the coating layer plate 52.

In this application, particulate matter that particulate trap is arranged in entrapment waste gas in integrated form nitrogen oxygen particulate trap 5, the diameter of particulate matter in a plurality of drill way is less than the waste gas on separation layer net 51, make the particulate matter in the waste gas behind the particulate trap entrapment, remaining waste gas particulate matter can be blockked outside separation layer net 51, can not enter into and paint plywood 52, make paint on the plywood 52 catalyst can fully react with the NOx in the waste gas, in this application, do not prescribe a limit to the catalyst of painting on the plywood 52, as long as can react with NOx and can effectually get rid of NOx can.

Optionally, a sealing rubber ring is arranged at the joint of the urea storage tank 4 and the primary urea nozzle 3, and a sealing rubber ring is arranged at the joint of the urea nozzle and the secondary urea nozzle 6; and an air tightness glue is coated at the joint of the second vent pipe 7 and the tail gas aftertreatment system 8, and the air tightness glue is used for preventing NOx or ammonia gas in the second vent pipe 7 from leaking outwards.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed to by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and the like.