Motor vehicle exhaust component concentration monitoring device

Abstract

The utility model relates to a motor vehicle exhaust component concentration monitoring device which comprises a Fourier analyzer, a sampling pump, a dilution unit and a sampling gun head, the Fourier analyzer is connected with the sampling pump through a pipeline, the sampling pump is connected with the sampling gun head through a pipeline, and the dilution unit is arranged on the pipeline between the sampling pump and the sampling gun head; the sampling pump is used for collecting motor vehicle tail gas through the sampling gun head and conveying the motor vehicle tail gas to the Fourier analyzer, the Fourier analyzer is used for analyzing pollutant components in the motor vehicle tail gas, and the detection device can filter oil drops in the tail gas and dilute the pollutant concentration.

Description

Technical Field

[0001] This utility model relates to a device for monitoring the concentration of components in motor vehicle exhaust gas, belonging to the field of exhaust gas monitoring technology. Background Technology

[0002] Currently, to obtain the characteristics of vehicle exhaust emissions, on-site analysis methods are commonly used for exhaust gas detection. This mainly utilizes portable emission monitoring devices, such as Portable Emission Measurement Systems (PEMS), to collect and detect exhaust gases. These devices can comprehensively record vehicle operating data and real-time pollutant emission levels under different operating conditions. However, existing PEMS mainly focus on monitoring CO, CO2, HC, NOx, etc., and cannot assess the emission levels of key reactive species such as VOCs. A few studies have supplemented the system by installing ammonia sensors to achieve real-time monitoring of ammonia emissions, but the installation of both types of devices is relatively cumbersome. Moreover, when directly collecting exhaust gases, oil stains in the exhaust gas may drip onto the filter element of the sampling device, and the high concentration of pollutants in the exhaust gas can affect the detection accuracy. Utility Model Content

[0003] In order to solve the problems existing in the prior art, this utility model provides a monitoring device that can filter oil droplets in exhaust gas and dilute the concentration of pollutants.

[0004] To achieve the above objectives, the technical solution proposed by this utility model is as follows: a motor vehicle exhaust component concentration monitoring device, comprising a Fourier analyzer, a sampling pump, a dilution unit, and a sampling nozzle; the Fourier analyzer is connected to the sampling pump via a pipeline, the sampling pump is connected to the sampling nozzle via a pipeline, and the dilution unit is disposed on the pipeline between the sampling pump and the sampling nozzle; the sampling pump is used to collect motor vehicle exhaust gas through the sampling nozzle and deliver it to the Fourier analyzer, which is used to analyze the pollutant components in the motor vehicle exhaust gas.

[0005] A further design of the above technical solution is as follows: the sampling end of the sampling gun head is provided with a metal filter membrane with a pore size of 1 micrometer.

[0006] The dilution unit includes a dilution channel in the pipeline between the sampling pump and the sampling nozzle, and an air compressor connected to the dilution channel.

[0007] Both the sampling nozzle and the sampling pump are connected to the dilution channel via a heat tracing pipe.

[0008] The sampling pump is connected to the Fourier analyzer via a heat tracing pipe.

[0009] The Fourier analyzer is equipped with a backflush port and an air outlet, and the backflush port is connected to a backflush unit.

[0010] The backflush unit includes an air source and a pressure reducing valve connected to the air source.

[0011] The backflush unit is connected to the backflush port of the Fourier analyzer and the sampling pump via pipes.

[0012] Compared with the prior art, this utility model has the following advantages:

[0013] This invention uses a Fourier transform infrared (FTIR) detector to simultaneously monitor pollutants in motor vehicle exhaust. A metal filter membrane is added to the front end of the sampling probe to filter out highly viscous fuel droplets in the exhaust, preventing these droplets from puncturing the filter element of the sampling gun and causing damage. A dilution channel is added to the front end of the sampling pump to reduce the concentration of pollutants in the exhaust, expanding the system's testable range and improving detection accuracy. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model;

[0015] In the diagram: 1-Fourier analyzer, 11-backflush port, 12-air outlet, 2-sampling pump, 3-dilution channel, 4-air compressor, 5-sampling nozzle, 51-metal filter membrane, 6-pressure reducing valve, 7-air source. Detailed Implementation

[0016] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Example 1

[0017] like Figure 1 As shown, the vehicle exhaust component concentration monitoring device of this embodiment includes a Fourier analyzer 1, a sampling pump 2, a dilution unit, and a sampling nozzle 5. The Fourier analyzer 1 is connected to the sampling pump 2 via a heat tracing pipe, and the sampling pump 2 is connected to the sampling nozzle 5 via a pipeline. In this embodiment, the dilution unit is disposed on the pipeline between the sampling pump 2 and the sampling nozzle 5. The dilution unit includes a dilution channel 3 disposed on the pipeline between the sampling pump 2 and the sampling nozzle 5 and an air compressor 4 connected to the dilution channel 3. The sampling nozzle 5 and the sampling pump 2 are both connected to the dilution channel 3 via heat tracing pipes.

[0018] Sampling pump 2 collects vehicle exhaust gas through sampling nozzle 5 and pumps the exhaust gas into Fourier analyzer 1. Fourier analyzer 1 is a Fourier transform infrared spectrometer that can simultaneously monitor the concentration of NO, NO2, CO2, VOCs and other species in vehicle exhaust gas. In this embodiment, the sampling nozzle 5 is equipped with a metal filter membrane 51 at the sampling end, wherein the pore size of the metal filter membrane 51 is 1 micrometer, which can filter out fuel droplets from the vehicle. The sampling nozzle is 2m long and made of stainless steel. The built-in filter element can further filter particulate matter to prevent contamination of the gas pool of the Fourier analyzer.

[0019] As the vehicle exhaust gas flows from the sampling nozzle 5 to the sampling pump 2, it passes through the dilution unit. The air compressor 4 of the dilution unit generates zero gas and inputs it into the dilution channel 3. The pollutants in the collected exhaust gas are uniformly mixed and diluted with the zero gas in the dilution channel 3, thereby avoiding excessive concentration of some pollutants from contaminating the Fourier analyzer and expanding the testable range of the system.

[0020] The sampling nozzle 5, dilution unit 3, sampling pump 2 and Fourier analyzer 1 are all connected by a heat tracing pipe, which can remove the water vapor generated by the vehicle exhaust during the cooling process to prevent contamination of the gas pool of Fourier analyzer 1 and interference with the detection results. Example 2

[0021] The motor vehicle exhaust component concentration monitoring device of this embodiment has a structure that is basically the same as that of Embodiment 1, except that: in this embodiment, the Fourier analyzer 1 is provided with a backflush port 11 and an outlet port 12, and the backflush port 11 is connected to a backflush unit; the gas introduced into the Fourier analyzer 1 is discharged through the outlet port 12. The backflush unit includes a gas source 7 and a pressure reducing valve 6 connected to the gas source 7. The gas source 7 can be a zero gas source or a standard gas source. In this embodiment, it is nitrogen. The backflush unit is connected to the backflush port 11 of the Fourier analyzer 1 and the sampling pump 2 through a hose. Valves are provided on the connected hoses. In this embodiment, before detection, the pressure reducing valve of the backflush unit is opened, and pure gas is introduced into the sampling pump 2 to calibrate the Fourier analyzer 1 and perform background measurement; after the exhaust gas is detected, the pressure reducing valve of the backflush unit is opened, and gas is introduced into the Fourier analyzer 1 and the sampling pump 2 to purge the pipeline and ensure that there is no residue in the entire pipeline of the analyzer and the sampling pump 2.

[0022] The technical solutions of this utility model are not limited to the above embodiments. All technical solutions obtained by equivalent substitution fall within the scope of protection claimed by this utility model.

Claims

1. A device for monitoring the concentration of components in motor vehicle exhaust gas, characterized in that: The system includes a Fourier transform analyzer, a sampling pump, a dilution unit, and a sampling nozzle. The Fourier transform analyzer is connected to the sampling pump via a pipeline, and the sampling pump is connected to the sampling nozzle via a pipeline. The dilution unit is located on the pipeline between the sampling pump and the sampling nozzle. The sampling pump is used to collect vehicle exhaust gas through the sampling nozzle and deliver it to the Fourier transform analyzer, which is used to analyze the pollutant components in the vehicle exhaust gas.

2. The motor vehicle exhaust component concentration monitoring device according to claim 1, characterized in that: The sampling end of the sampling gun head is equipped with a metal filter membrane with a pore size of 1 micrometer.

3. The motor vehicle exhaust component concentration monitoring device according to claim 1, characterized in that: The dilution unit includes a dilution channel in the pipeline between the sampling pump and the sampling nozzle, and an air compressor connected to the dilution channel.

4. The motor vehicle exhaust component concentration monitoring device according to claim 3, characterized in that: Both the sampling nozzle and the sampling pump are connected to the dilution channel via a heat tracing pipe.

5. The motor vehicle exhaust component concentration monitoring device according to claim 1, characterized in that: The sampling pump is connected to the Fourier analyzer via a heat tracing pipe.

6. The motor vehicle exhaust component concentration monitoring device according to claim 1, characterized in that: The Fourier analyzer is equipped with a backflush port and an air outlet, and the backflush port is connected to a backflush unit.

7. The motor vehicle exhaust component concentration monitoring device according to claim 6, characterized in that: The backflush unit includes an air source and a pressure reducing valve connected to the air source.

8. The motor vehicle exhaust component concentration monitoring device according to claim 6, characterized in that: The backflush unit is connected to the backflush port of the Fourier analyzer and the sampling pump via pipes.

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