Portable pollution source emission on-line measuring device

Abstract

The utility model relates to the field of environment monitoring technology application, in particular to a portable pollution source emission on-line measurement device which comprises a tail gas sampling and pretreatment module, a formaldehyde and nitrous acid on-line analysis module, a conventional gas expansion module and a data acquisition and main control module, the tail gas sampling and pretreatment module is respectively connected with the formaldehyde and nitrous acid online analysis module and the conventional gas expansion module, the formaldehyde and nitrous acid online analysis module is connected with the data acquisition and main control module, and the conventional gas expansion module is connected with the data acquisition and main control module. The automobile exhaust emission flow temperature is monitored, formaldehyde and nitrous acid are measured through the formaldehyde and nitrous acid on-line analysis module, data recording is carried out through the conventional gas expansion module, and finally the data of formaldehyde and nitrous acid are stored and monitored through the data acquisition and main control module. Therefore, active components such as formaldehyde and nitrous acid discharged from the motor vehicle tail gas road can be measured.

Description

TECHNICAL FIELD

[0001] The utility model belongs to environmental monitoring technical application field, concretely relates to a portable pollution source emission on -line measuring device. BACKGROUND

[0002] In recent years, the motor vehicle population in China grows rapidly, and motor vehicles bring convenience to human life, but also have an important impact on the atmospheric environment and human health. Motor vehicles produce exhaust gas in the use process, which contains hundreds of different compounds, and the pollutants include solid suspended particles, carbon monoxide, carbon dioxide, hydrocarbons, nitrogen oxides, lead and sulfur oxides, etc. At present, the main pollutants for motor vehicle exhaust detection are CO, CO2, NO, NO2, THC and PM, etc.

[0003] Formaldehyde (HCHO) and nitrous acid (HONO) are important precursors of atmospheric radicals, and motor vehicle exhaust emission is one of the main primary sources of formaldehyde and nitrous acid. At present, the research on formaldehyde and nitrous acid measurement equipment for motor vehicle emission is very insufficient, especially for the on-line measurement device for formaldehyde and nitrous acid on vehicles. Due to the high temperature and high heat characteristics of motor vehicle exhaust emission, formaldehyde and nitrous acid are high active components, which are different from conventional pollutant components, and are more likely to cause loss in the sampling pipeline and pretreatment process, so that it is impossible to measure the key active components such as formaldehyde and nitrous acid in real time. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a portable pollution source emission on-line measuring device, which solves the problem that the existing measuring device cannot measure the key active components such as formaldehyde and nitrous acid in real time due to the high temperature and high heat characteristics of motor vehicle exhaust emission, and formaldehyde and nitrous acid are high active components, which are different from conventional pollutant components, and are more likely to cause loss in the sampling pipeline and pretreatment process.

[0005] To achieve the above technical purpose, the utility model adopts the following technical scheme:

[0006] The utility model provides a portable pollution source emission on-line measuring device, which comprises an exhaust gas sampling and pretreatment module, a formaldehyde and nitrous acid on-line analysis module, a conventional gas expansion module and a data acquisition and main control module, the exhaust gas sampling and pretreatment module is connected with the formaldehyde and nitrous acid on-line analysis module and the conventional gas expansion module respectively, the formaldehyde and nitrous acid on-line analysis module is connected with the data acquisition and main control module, and the conventional gas expansion module is connected with the data acquisition and main control module.

[0007] The tail gas sampling and pretreatment module comprises a tail gas sampling unit and a three-stage dilution unit, the tail gas sampling unit is connected with the three-stage dilution unit, the tail gas sampling unit is connected with the conventional gas expansion module, and the three-stage dilution unit is connected with the formaldehyde and nitrous acid online analysis module.

[0008] The formaldehyde and nitrous acid online analysis module comprises a low-temperature sampling unit, a constant-temperature reaction unit, a constant-temperature detection unit and a data acquisition control unit, the data acquisition control unit is connected with the low-temperature sampling unit, the constant-temperature reaction unit and the constant-temperature detection unit respectively, the data acquisition control unit is connected with the data acquisition and main control module, the low-temperature sampling unit is connected with the three-stage dilution unit and the constant-temperature reaction unit respectively, and the constant-temperature reaction unit is connected with the constant-temperature detection unit.

[0009] The conventional gas expansion module comprises a sample gas pretreatment unit, a conventional gas detection unit and a data acquisition control unit, and the sample gas pretreatment unit, the conventional gas detection unit and the data acquisition control unit are sequentially connected.

[0010] The sample gas pretreatment unit mainly comprises a constant-temperature device, a particulate matter filter, a water-gas separator and a drying tube, the constant-temperature device, the particulate matter filter, the water-gas separator and the drying tube are all installed in a conventional gas detection case, the constant-temperature device is wrapped outside the particulate matter filter, and the water-gas separator and the drying tube are connected behind the particulate matter filter.

[0011] The portable pollution source emission online measurement device is connected with the formaldehyde and nitrous acid online analysis module and the conventional gas expansion module, the formaldehyde and nitrous acid online analysis module is connected with the data acquisition and main control module, the conventional gas expansion module is connected with the data acquisition and main control module, the data acquisition and main control module controls the tail gas sampling and pretreatment module, the formaldehyde and nitrous acid online analysis module and the conventional gas expansion module in a wired or wireless mode, automobile exhaust is introduced into the tail gas sampling and pretreatment module, the real-time emission flow and temperature of the pretreated and monitored exhaust are measured, the formaldehyde and nitrous acid online analysis module is used for measuring the formaldehyde and nitrous acid in the exhaust, the wet chemical and optical monitoring technology is adopted, the formaldehyde and nitrous acid are synchronously and online measured, data is recorded through the conventional gas expansion module, and finally the data of the formaldehyde and nitrous acid is stored and monitored through the data acquisition and main control module, so that the real-time measurement of the actual road emission of the formaldehyde and nitrous acid and other key active components in automobile exhaust can be realized. BRIEF DESCRIPTION OF DRAWINGS

[0012] The utility model can be further illustrated by the non-limiting embodiments shown in the drawings.

[0013] Figure 1 is the structural diagram of the portable pollution source emission on-line measuring device of the first embodiment of the present application.

[0014] Figure 2 is the principle diagram of the formaldehyde and nitrous acid on-line analysis module of the first embodiment of the present application.

[0015] Figure 3 is the installation structure schematic diagram of the flow tube of the second embodiment of the present application.

[0016] Figure 4 is the installation structure schematic diagram of the pretreatment main body case of the second embodiment of the present application.

[0017] Figure 5 is the installation structure schematic diagram of the second layer partition plate of the second embodiment of the present application.

[0018] Figure 6 is the installation structure schematic diagram of the first air pump of the second embodiment of the present application.

[0019] Figure 7 is the installation structure schematic diagram of the measuring case of the second embodiment of the present application.

[0020] Figure 8 is the principle diagram of the conventional gas expansion module of the third embodiment of the present application.

[0021] Figure 9 is the installation structure schematic diagram of the conventional gas expansion module of the third embodiment of the present application.

[0022] In the figure: 1-tail gas sampling and pretreatment module, 2-formaldehyde and nitrous acid online analysis module, 3-conventional gas expansion module, 4-data acquisition and main control module, 101-tail gas sampling unit, 102-three-stage dilution unit, 1011-flow tube, 1012-sampling port, 1013-velocity meter, 1021-pretreatment main body case, 1022-two-layer partition, 1023-first air pump, 1024-second air pump, 1025-first mass flow controller, 1026-second mass flow controller, 1027-third mass flow controller, 201-low temperature sampling unit, 202-constant temperature reaction unit, 203-constant temperature detection unit, 204-data acquisition control unit, 2011-measuring case, 2012-HCHO glass screw pipe, 2013-HONO glass screw pipe, 2014-absorption liquid bottle, 2015-reaction liquid bottle, 301-sample gas pretreatment unit, 302-conventional gas detection unit, 303-data acquisition control unit, 3011-constant temperature device, 3012-particulate filter, 3013-water gas separator, 3014-dry tube, 3021-conventional gas sensor, 3022-air pump, 3023-gas flow meter, 3031-data acquisition control circuit board. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the present application, the technical scheme of the present application will be further described below in combination with the drawings and examples.

[0024] The first embodiment of the present application is:

[0025] Please refer to Figure 1 and Figure 2 , wherein Figure 1 is a structure block diagram of the portable pollution source emission online measurement device of the first embodiment of the present application, Figure 2 is a principle block diagram of the formaldehyde and nitrous acid online analysis module of the first embodiment of the present application.

[0026] The utility model provides a portable pollution source discharge on -line measuring device: including tail gas sampling and pretreatment module 1, formaldehyde and nitrous acid on -line analysis module 2, conventional gas extension module 3 and data acquisition and main control module 4, tail gas sampling and pretreatment module 1 is connected with formaldehyde and nitrous acid on -line analysis module 2 and conventional gas extension module 3 respectively, formaldehyde and nitrous acid on -line analysis module 2 is connected with data acquisition and main control module 4, conventional gas extension module 3 is connected with data acquisition and main control module 4, tail gas sampling and pretreatment module 1 is used for monitoring tail gas real -time discharge flow, temperature and avoiding the condensation of tail gas in the sampling process, and simultaneously pretreating tail gas, formaldehyde and nitrous acid on -line analysis module 2 adopts wet chemistry and optical monitoring technology, and synchronously measures formaldehyde and nitrous acid, conventional gas extension module 3 is used for monitoring conventional gas and detecting environmental meteorology, data acquisition and main control module 4 is used for system control, real -time monitoring and data storage.

[0027] Wherein, the tail gas sampling and pretreatment module 1 includes tail gas sampling unit 101 and three-stage dilution unit 102, the tail gas sampling unit 101 is connected with the three-stage dilution unit 102, the tail gas sampling unit 101 is connected with the conventional gas extension module 3, the three-stage dilution unit 102 is connected with the formaldehyde and nitrous acid on -line analysis module 2, the tail gas sampling unit 101 monitors tail gas real -time discharge flow and temperature, the three-stage dilution unit 102 is used for dilution pretreatment to sampling tail gas, reduces the heat preservation energy consumption and condensation loss in tail gas sampling process, obtains the dilution effect of high dilution ratio, simultaneously, realizes the dilution ratio adjustment of wide range, adapts to different motor vehicle tail gas emission pollutant concentration range, guarantees the detection result.

[0028] Secondly, the formaldehyde and nitrous acid online analysis module 2 comprises a low-temperature sampling unit 201, a constant-temperature reaction unit 202, a constant-temperature detection unit 203 and a data acquisition control unit 204, the data acquisition control unit 204 is connected with the low-temperature sampling unit 201, the constant-temperature reaction unit 202 and the constant-temperature detection unit 203 respectively; the data acquisition control unit 204 is connected with the data acquisition and main control module 4; the low-temperature sampling unit 201 is connected with the three-stage dilution unit 102 and the constant-temperature reaction unit 202 respectively; the constant-temperature reaction unit 202 is connected with the constant-temperature detection unit 203, the low-temperature sampling unit 201 adopts a corresponding spiral tube as a gaseous pollutant diffusion trapping trap, an outer chamber is wrapped with cooling water, so that the trapping temperature is kept at 10-20℃, and the high efficiency of trapping of formaldehyde and nitrous acid is ensured; the constant-temperature reaction unit 202 adopts a heating rod to heat the solution, accelerates the reaction speed between substances, and makes the substances constant temperature at 60℃; the constant-temperature detection unit 203 applies a high-sensitivity double-channel detection flow cell, combines a double-channel total reflection long optical path online flow cell and rapid absorption spectrum detection to realize rapid and sensitive and ultra-wide range detection of formaldehyde and nitrous acid; the data acquisition control unit 204 respectively collects and controls data of the low-temperature sampling unit 201, the constant-temperature reaction unit 202 and the constant-temperature detection unit 203, and supplies power.

[0029] Finally, the conventional gas expansion module 3 comprises a sample gas pretreatment unit 301, a conventional gas detection unit 302 and a data acquisition control unit 303, the data acquisition control unit 303 is connected with the sample gas pretreatment unit 301 and the conventional gas detection unit 302 respectively; the data acquisition control unit 303 is connected with the data acquisition and main control module 4; the sample gas pretreatment unit 301 is connected with the tail gas sampling unit 101 and the conventional gas detection unit 302 respectively, the sample gas pretreatment unit 301 adopts a particulate filter, a water-gas separator and a drying tube to remove particulates and moisture in the tail gas, so as to avoid interference with the conventional gas detection unit such as NO2, the particulate filter is wrapped with a constant-temperature device, so that the temperature of the particulate filter is kept at 100℃, so as to avoid damage of water vapor to the particulate filter, thereby prolonging the service life of the particulate filter; the conventional gas detection unit 302 adopts a sensor based on NDUV and NDIR method to detect the concentration of conventional gases such as NO2 and CO2; the data acquisition control unit 303 respectively collects and controls data of the sample gas pretreatment unit 301 and the conventional gas detection unit 302, and supplies power.

[0030] In the embodiment, the data acquisition and main control module 4 controls the exhaust sampling unit 101, the three-stage dilution unit 102, the data acquisition control unit 204 and the conventional gas expansion module 3 through wired or wireless mode, the automobile exhaust is introduced into the exhaust sampling unit 101, the flow and temperature of the exhaust are monitored, the conventional gas is monitored through the conventional gas expansion module 3, the formaldehyde and the nitrous acid are diluted through the three-stage dilution unit 102, the data acquisition control unit 204 controls the low-temperature sampling unit 201, the constant-temperature reaction unit 202 and the constant-temperature detection unit 203, the processed exhaust is introduced into the low-temperature sampling unit 201 and kept at 10-20 DEG C, the formaldehyde and the nitrous acid are captured, the exhaust is introduced into the constant-temperature reaction unit 202, the temperature is increased, the constant temperature is kept at 60 DEG C, the formaldehyde and the nitrous acid are detected in the constant-temperature detection unit 203, the data acquisition control unit 204 collects data and feeds back to the data acquisition and main control module 4, so that the formaldehyde and the nitrous acid and other key active components in the automobile exhaust on the actual road can be measured in real time.

[0031] The second embodiment of the application is:

[0032] Please refer to Figures 3 to 7 , wherein Figure 3 is the installation structure schematic diagram of the flow pipe of the second embodiment of the utility model, Figure 4 is the installation structure schematic diagram of the pretreatment main body case of the second embodiment of the utility model, Figure 5 is the installation structure schematic diagram of the two-layer partition plate of the second embodiment of the utility model, Figure 6 is the installation structure schematic diagram of the first air pump of the second embodiment of the utility model, Figure 7 is the installation structure schematic diagram of the measurement case of the second embodiment of the utility model.

[0033] The exhaust sampling unit 101 includes a flow pipe 1011, a sampling port 1012 and a speedometer 1013, the three-stage dilution unit 102 includes a pretreatment main body case 1021, a two-layer partition plate 1022, a first air pump 1023, a second air pump 1024, a first mass flow controller 1025, a second mass flow controller 1026 and a third mass flow controller 1027, and the low-temperature sampling unit 201 includes a measurement case 2011, an HCHO glass screw pipe 2012, an HONO glass screw pipe 2013, an absorption liquid bottle 2014 and a reaction liquid bottle 2015.

[0034] The sampling port 1012 is fixedly installed on the flow tube 1011, and the sampling port 1012 communicates with the flow tube 1011; the flowmeter 1013 is installed on the sampling port 1012, and the sampling port 1012 transports the tail gas; the flow tube 1011 is fixed on the motor vehicle tail gas pipe through stainless steel, so that the tail gas enters the flowmeter 1013 through the flow tube 1011 and the sampling port 1012, and the flowmeter 1013 monitors the flow and temperature of the tail gas.

[0035] Secondly, the two-layer partition plate 1022 is fixedly installed in the front treatment main body case 1021; the first air pump 1023 is fixedly installed in the front treatment main body case 1021; the second air pump 1024 is fixedly installed in the front treatment main body case 1021; the first mass flow controller 1025 is fixedly installed in the front treatment main body case 1021, and the first mass flow controller 1025 communicates with the sampling port 1012; the second mass flow controller 1026 is fixedly installed in the front treatment main body case 1021, and the second mass flow controller 1026 communicates with the first mass flow controller 1025; the third mass flow controller 1027 is fixedly installed in the front treatment main body case 1021, and the third mass flow controller 1027 communicates with the second mass flow controller 1026, the front treatment main body case 1021 controls the dilution of the tail gas, and the first mass flow controller 1025, the second mass flow controller 1026 and the third mass flow controller 1027 are used for controlling the tail gas and diluting the sampled tail gas before treatment; the first air pump 1023 and the second air pump 1024 pump the tail gas.

[0036] Finally, the HCHO glass threaded pipe 2012 is installed in the measuring cabinet 2011, the HONO glass threaded pipe 2013 is installed in the measuring cabinet 2011, the HCHO glass threaded pipe 2012 is connected in parallel with the HONO glass threaded pipe 2013; the absorption liquid bottle 2014 is fixedly installed in the measuring cabinet 2011, the absorption liquid bottle 2014 is communicated with the HCHO glass threaded pipe 2012; the reaction liquid bottle 2015 is fixedly installed in the measuring cabinet 2011, the reaction liquid bottle 2015 is communicated with the absorption liquid bottle 2014, the measuring cabinet 2011 is used for monitoring and synchronously online measuring formaldehyde and nitrous acid in tail gas; the HCHO glass threaded pipe 2012 and the HONO glass threaded pipe 2013 capture formaldehyde and nitrous acid, so that the temperature of formaldehyde and nitrous acid is kept at 10-20 degrees Celsius; the absorption liquid bottle 2014 controls temperature; the reaction liquid bottle 2015 is used for formaldehyde and nitrous acid reaction; the measuring cabinet 2011 is installed with a temperature control board, a reactor and a detector, the temperature control board controls temperature, and the temperature is kept constant at 60 degrees Celsius, and the detector detects sensitivity and super wide range of formaldehyde and nitrous acid.

[0037] In use, the flow pipe 1011 is fixed on the tail gas pipe of a motor vehicle through stainless steel, tail gas enters the flow pipe 1011 and the sampling port 1012, the flow and temperature of the tail gas are monitored by the flowmeter 1013, and then the tail gas enters the first mass flow controller 1025, the second mass flow controller 1026 and the third mass flow controller 1027 through the sampling port 1012 in sequence, and is subjected to pre-dilution treatment, the first air pump 1023 and the second air pump 1024 pump the tail gas, the HCHO glass threaded pipe 2012 and the HONO glass threaded pipe 2013 capture formaldehyde and nitrous acid, so that the temperature of formaldehyde and nitrous acid is kept at 10-20 degrees Celsius; the absorption liquid bottle 2014 controls temperature; the reaction liquid bottle 2015 is used for formaldehyde and nitrous acid reaction; the measuring cabinet 2011 is installed with a temperature control board, a reactor and a detector, the temperature control board controls temperature, and the temperature is kept constant at 60 degrees Celsius, and the detector detects sensitivity and super wide range of formaldehyde and nitrous acid, so as to monitor formaldehyde and nitrous acid in real time.

[0038] The above only discloses one or more preferred embodiments of the application, and cannot limit the scope of the application. Those skilled in the art can understand that all or part of the above-mentioned processes can be implemented, and equivalent changes made according to the claims of the application still belong to the scope covered by the application.

[0039] The third embodiment of the present application is as follows:

[0040] Please refer to Figure 8 and Figure 9 , Figure 8 is a principle block diagram of the conventional gas expansion module of the third embodiment of the present application, Figure 9 is a schematic diagram of the installation structure of the conventional gas expansion module of the third embodiment of the present application.

[0041] In the present embodiment, the conventional gas expansion module 3 comprises a sample gas pre-treatment unit 301, a conventional gas detection unit 302 and a data acquisition control unit 303.

[0042] The sample gas pre-treatment unit 301 comprises a constant temperature device 3011, a particulate filter 3012, a water-gas separator 3013 and a drying tube 3014, the conventional gas detection unit 302 comprises a conventional gas sensor 3021 based on the NDUV and NDIR methods, a gas pump 3022 and a gas flow meter 3023, and the data acquisition control unit 303 comprises a data acquisition control circuit board 3031.

[0043] The particulate filter 3012 is fixedly installed at the air inlet of the conventional gas expansion module case, the air inlet of the conventional gas expansion module case is connected with the tail gas sampling unit 101, the constant temperature device 3011 is wrapped outside the particulate filter 3012, the data acquisition control circuit board 3031 is fixedly installed in the conventional gas expansion module case and has temperature control and power supply functions, controls the constant temperature device 3011 to be constant at 100 DEG C, the water-gas separator 3013 is fixedly installed in the conventional gas expansion module case and communicates with the particulate filter 3012, and the drying tube 3014 is fixedly installed in the conventional gas expansion module case and is connected behind the water-gas separator 3013, so as to ensure that the humidity of the sample gas meets the detection requirements of the conventional gas sensor 3021.

[0044] Then, the sample gas from the water-gas separator 3013 enters the conventional gas sensor 3021 for conventional gas concentration monitoring, the gas flow meter 3023 communicates with the gas outlet of the conventional gas sensor 3021, controls the gas flow rate of the whole conventional gas expansion module 3, the gas pump 3022 is connected behind the gas flow meter 3023 and performs air extraction on the detection sample gas, the data acquisition control circuit board 3031 supplies power to the conventional gas sensor 3021, the gas flow meter 3023 and the gas pump 3022, and the data acquisition control circuit board 3031 also has a data acquisition function and can real-time acquire the flow data returned by the gas flow meter 3023 and the detection concentration data returned by the conventional gas sensor 3021.

[0045] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not intended to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical concept disclosed by the present application should be covered by the claims of the present application.

Claims

1. A portable pollution source emission on-line measurement device, characterized in that: it comprises a tail gas sampling and pretreatment module, a formaldehyde and nitrous acid on-line analysis module, a conventional gas expansion module and a data acquisition and main control module, the tail gas sampling and pretreatment module is connected with the formaldehyde and nitrous acid on-line analysis module and the conventional gas expansion module respectively, the formaldehyde and nitrous acid on-line analysis module is connected with the data acquisition and main control module, and the conventional gas expansion module is connected with the data acquisition and main control module; the tail gas sampling and pretreatment module comprises a tail gas sampling unit and a three-stage dilution unit, the tail gas sampling unit is connected with the three-stage dilution unit, the tail gas sampling unit is connected with the conventional gas expansion module, and the three-stage dilution unit is connected with the formaldehyde and nitrous acid on-line analysis module; the formaldehyde and nitrous acid on-line analysis module comprises a low-temperature sampling unit, a constant-temperature reaction unit, a constant-temperature detection unit and a data acquisition control unit, the data acquisition control unit is connected with the low-temperature sampling unit, the constant-temperature reaction unit and the constant-temperature detection unit respectively, and the data acquisition control unit is connected with the data acquisition and main control module, the low-temperature sampling unit is connected with the three-stage dilution unit and the constant-temperature reaction unit respectively, and the constant-temperature reaction unit is connected with the constant-temperature detection unit; the low-temperature sampling unit uses a corresponding spiral tube as a gaseous pollutant diffusion trapping trap, and the outer chamber is wrapped with cooling water; the constant-temperature reaction unit uses a heating rod to heat the solution.

2. The portable pollution source emission on-line measurement device according to claim 1, characterized in that: the conventional gas expansion module comprises a sample gas pretreatment unit, a conventional gas detection unit and a data acquisition control unit, and the sample gas pretreatment unit, the conventional gas detection unit and the data acquisition control unit are connected in sequence.

3. The portable pollution source emission on-line measurement device according to claim 2, characterized in that: the sample gas pretreatment unit mainly comprises a constant-temperature device, a particulate matter filter, a water-gas separator and a drying tube, the constant-temperature device, the particulate matter filter, the water-gas separator and the drying tube are all installed in a conventional gas detection case, the constant-temperature device is wrapped outside the particulate matter filter, and the water-gas separator and the drying tube are connected behind the particulate matter filter.

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