Evaluation system for particulate matter mass concentration monitoring equipment

Abstract

The utility model relates to an evaluation system for particulate matter mass concentration monitoring equipment, which comprises a gas flow standard device which is configured to at least judge whether the sampling flow of equipment to be evaluated is accurate or not; the temperature and humidity generating device is configured to at least generate fluid with controllable temperature and humidity so as to at least judge whether the temperature and humidity measurement of the to-be-evaluated equipment is accurate or not; the particulate matter generating device is configured to at least generate particulate matter fluid with controllable concentration so as to at least judge whether the mass concentration measurement of the to-be-evaluated equipment is accurate or not; and the manual sampling device is configured to at least judge whether the dynamic heating unit of the to-be-evaluated equipment is reliable or not.

Description

Technical Field

[0001] The utility model relates to the technical field of environmental monitoring, in particular to an evaluation system for particulate matter mass concentration monitoring equipment. Background Art

[0002] Routine monitoring items for ambient air mainly include sulfur dioxide, nitrogen oxides, carbon monoxide, ozone, fine particulate matter (PM 10 ) and inhalable particulate matter (PM 2.5 ), of which PM 2.5 PM2.5 concentration monitoring is a top priority in my country's environmental protection work. Since 2013, 339 prefecture-level cities and key regions, counties, and townships across the country have been carrying out PM2.5 concentration monitoring. 2.5 The automatic monitoring work of mass concentration is the data of PM 2.5 Mass concentration evaluation index and important assessment basis for environmental governance.

[0003] Current PM 2.5 There are different methods for evaluating the measurement accuracy of mass concentration monitoring equipment in the field of environmental monitoring and measurement. In the field of environmental monitoring, the main reference is the Chinese industry standard HJ 653-2021 "Ambient Air Particulate Matter (PM 10 and PM 2.5 ) Continuous Automatic Monitoring System Technical Requirements and Testing Methods, HJ 655-2013 "Ambient Air Particulate Matter (PM 10 and PM 2.5 ) Continuous Automatic Monitoring System Installation and Acceptance Technical Specifications and other relevant specifications, use standard membranes, flow meters, thermometers and hygrometers and other measurement standard instruments to confirm the influence of parameters such as mass, flow (volume), temperature, humidity and other parameters on mass concentration through calibration / comparison, and then compare with the gravimetric method for a long time to confirm that the comparison slope is within the range of 1±0.10 and the intercept is within ±5ug / m 3 Within the range, it is considered that PM 2.5 The mass concentration monitoring equipment data is accurate. The mass concentration converted by the standard membrane used in this method is much higher than the mass of particulate matter in the ambient air, and it is impossible to confirm the PM 2.5 The accuracy of the mass sensor of the mass concentration monitoring equipment and the accuracy of temperature and humidity measurements are confirmed by single-point comparison, which cannot reflect the linear relationship of temperature and humidity calibration.

[0004] The measurement field mainly refers to JJF 1659-2017《PM 2.5 Calibration Specifications for Mass Concentration Meters 2.5The metrological calibration of mass concentration monitoring equipment uses ISO A1 dust to generate particulate matter gases of different mass concentrations, such as low, medium and high, to carry out metrological calibration of mass concentration sensors. If the error of the indication does not exceed ±30%, the monitoring equipment data is considered accurate. This method only calibrates the mass concentration sensor and ignores the dynamic system's effect on PM. 2.5 The influence of mass concentration monitoring equipment, especially under the high temperature and high humidity weather conditions in the south, can easily lead to inconsistencies between monitoring data and weight method monitoring data. Utility Model Content

[0005] In view of the above analysis, the present invention aims to provide an evaluation system for particulate matter mass concentration monitoring equipment to at least solve one of the above problems.

[0006] The purpose of this utility model is mainly achieved through the following technical solutions:

[0007] The utility model provides an evaluation system for particulate matter mass concentration monitoring equipment, comprising:

[0008] A gas flow standard device configured to at least determine whether the sampling flow of the device to be evaluated is accurate;

[0009] A temperature and humidity generating device configured to at least generate a fluid with controllable temperature and humidity, so as to at least determine whether the temperature and humidity measurements of the device to be evaluated are accurate;

[0010] a particle generating device configured to generate at least a particulate flow of controlled concentration to at least determine whether the mass concentration measurement of the device to be evaluated is accurate;

[0011] The manual sampling device is configured to at least determine whether the dynamic heating unit of the device to be evaluated is reliable.

[0012] Furthermore, the gas flow standard device includes a standard flow meter, which is configured to be detachably installed in a sampling channel of the device to be evaluated so as to be able to test the sampling flow in the sampling channel.

[0013] Furthermore, the temperature and humidity generating device includes an air inlet, a mixing chamber and an air pump;

[0014] A first air path and a second air path connected in parallel are provided between the air inlet end and the mixing chamber;

[0015] The first gas path is provided with a water reservoir to prepare the gas entering the first gas path to be converted into wet gas with humidity, and to guide the wet gas into the mixing chamber;

[0016] The second air path introduces air or dried air into the mixing chamber;

[0017] The air extraction pump is configured to allow external air to enter the temperature and humidity generating device from the air inlet end;

[0018] The mixing chamber is provided with a mixing cavity, which is in communication with the first gas path and the second gas path, so as to mix the fluid introduced from the first gas path and the second gas path;

[0019] The mixing chamber is further provided with a heater and a standard thermometer and hygrometer. The heater is configured to heat the fluid in the mixing chamber to a preset temperature, and the standard thermometer and hygrometer is configured to test the temperature and humidity of the fluid in the mixing chamber.

[0020] Furthermore, the first gas path is provided with a first flow controller, and the first flow controller is configured to at least control the flow rate of the fluid entering the mixing chamber through the first gas path;

[0021] The second gas path is provided with a second flow controller, and the second flow controller is configured to at least control the flow of the fluid entering the mixing chamber through the second gas path.

[0022] Furthermore, the particle generating device includes a gas supply component, a liquid supply component and an atomizing component, and the atomizing component is communicated with the gas supply component and the liquid supply component respectively;

[0023] The gas supply component is configured to provide a quantitative amount of clean gas to the atomization component;

[0024] The liquid supply component is configured to provide a quantitative amount of liquid to the atomization component;

[0025] The atomizing assembly is configured to mix and disperse the gas provided by the gas providing assembly and the liquid provided by the liquid providing assembly into a particulate fluid.

[0026] Further, the gas supply assembly includes a connected air compressor and filter element;

[0027] The air compressor is configured to convert external air into compressed air and to measure the flow rate of the compressed air;

[0028] The filter element is configured to remove impurities from the compressed air;

[0029] The inlet of the filter element is connected to the air compressor, and the outlet of the filter element is communicated with the air inlet of the atomizing assembly so as to provide the filtered compressed air to the atomizing assembly.

[0030] Further, the liquid providing assembly includes a connected liquid reservoir and a syringe pump;

[0031] The liquid reservoir is configured to store liquid provided to the atomizing assembly;

[0032] The syringe pump is configured to provide the liquid to the nebulizer assembly in a quantitative manner.

[0033] Furthermore, the liquid supply assembly includes a plurality of syringe pumps, and the plurality of syringe pumps are connected to the liquid reservoir in parallel.

[0034] Furthermore, the atomization assembly includes an atomizer and a mixing chamber;

[0035] The atomizer is provided with a liquid inlet in communication with the liquid supply assembly, and the atomizer is configured to break up the liquid into droplets and introduce the droplets into the mixing chamber;

[0036] The mixing chamber is provided with an outlet and an air inlet connected to the gas supply assembly. After the liquid droplets and the gas are evenly mixed in the mixing chamber, they are guided out of the atomization assembly through the air outlet.

[0037] Furthermore, the manual sampling device includes a sampling pump, a flow control device, a standard membrane assembly and a weighing assembly;

[0038] The flow controller and the sampling pump are configured to jointly control the flow of the particulate fluid reaching the standard filter membrane and simultaneously control the sampling time;

[0039] The standard membrane assembly includes a standard filter membrane and a membrane support, and the standard filter membrane is mounted on the membrane support;

[0040] The weighing assembly is configured to be able to weigh the mass of a standard membrane assembly.

[0041] Compared with the existing technology, the present invention can achieve at least one of the beneficial effects: fully consider the factors affecting the particulate matter mass concentration monitoring equipment, evaluate the accuracy of the flow sensor, temperature and humidity sensor, and mass concentration sensor of the monitoring equipment, and calibrate the equipment to be evaluated based on the evaluation results, thereby improving the accuracy of the equipment to be evaluated.

[0042] In the present invention, the above-mentioned technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of the present invention will be described in the following content, and some advantages will become apparent from the description or be understood through practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the text and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The accompanying drawings are only used for the purpose of illustrating specific embodiments and are not to be considered as limiting the present invention. Throughout the accompanying drawings, the same reference symbols denote the same components.

[0044] Figure 1 It is a structural block diagram of the evaluation system evaluating the device to be evaluated in a specific implementation manner;

[0045] Figure 2 It is a structural schematic diagram of a temperature and humidity generating device in a specific embodiment;

[0046] Figure 3 It is a structural schematic diagram of a particle generating device in a specific implementation manner.

[0047] Reference numerals:

[0048] 1-Gas flow standard device; 2-Temperature and humidity generating device; 201-First gas path; 202-Second gas path; 21-Air inlet; 22-Mixing chamber; 221-Standard temperature and humidity meter; 23-Suction pump; 24-Water reservoir; 25-Dryer; 3-Particle generating device; 31-Gas supply assembly; 311-Air compressor; 312-Filter element; 32-Liquid supply assembly; 321-Liquid reservoir; 322-Syringe pump; 33-Atomization assembly; 33a-Air inlet; 33b-Liquid inlet; 33c-Liquid outlet; 331-Atomizer; 332-Mixing chamber; 4-Manual sampling device; 5-Equipment to be evaluated. DETAILED DESCRIPTION

[0049] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, and are not used to limit the scope of the present invention.

[0050] In the description of the embodiments of the present invention, it should be noted that, unless otherwise expressly specified or limited, the term "connected" should be understood in a broad sense. For example, it can mean a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection, an electrical connection, a direct connection, or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present invention can be understood according to the specific circumstances.

[0051] The terms "top," "bottom," "above," "below," and "on" used throughout the description refer to relative positions of components of a device, such as the relative positions of top and bottom substrates within a device. It will be understood that devices are multifunctional regardless of their orientation in space.

[0052] The working surface of the present invention can be a plane or a curved surface, can be inclined, or can be horizontal. For the convenience of description, the present invention is placed on a horizontal surface and used on a horizontal surface, and "high and low" and "up and down" are defined in this way.

[0053] A specific embodiment of the present invention discloses an evaluation system for particulate matter mass concentration monitoring equipment (hereinafter referred to as the evaluation system), which can at least be used for PM 2.5 Evaluation of mass concentration monitoring equipment, that is, the utility model discloses at least one method for PM 2.5 Evaluation system for mass concentration monitoring equipment.

[0054] like Figures 1 to 3 As shown, the evaluation system includes:

[0055] The gas flow standard device 1 is configured to at least determine whether the sampling flow of the device to be evaluated 5 is accurate;

[0056] The temperature and humidity generating device 2 is configured to generate at least a fluid with controllable temperature and humidity, so as to at least determine whether the temperature and humidity measurements of the device to be evaluated 5 are accurate;

[0057] The particle generating device 3 is configured to generate at least a particle flow with a controllable concentration, so as to at least determine whether the mass concentration measurement of the device to be evaluated 5 is accurate;

[0058] The manual sampling device 4 is configured to at least determine whether the dynamic heating unit of the device to be evaluated 5 is reliable.

[0059] The device to be evaluated 5 refers to a particulate matter mass concentration monitoring device, such as PM 2.5 Mass concentration monitoring equipment.

[0060] The evaluation system of the utility model fully considers the factors affecting the particulate matter mass concentration monitoring equipment, evaluates the accuracy of the flow sensor, temperature and humidity sensor, and mass concentration sensor of the monitoring equipment, and calibrates the equipment to be evaluated based on the evaluation results, thereby improving the accuracy of the equipment to be evaluated.

[0061] The gas flow standard device 1 includes a standard flow meter, which is configured to be detachably installed in the sampling channel of the device to be evaluated so as to be able to test the sampling flow in the sampling channel. After the standard flow meter is assembled in the sampling channel, the device to be evaluated is sampled at a flow rate L, that is, the sampling flow rate is L, and the flow data measured by the standard flow meter is the standard flow rate Ls. When the flow measurement error △L=100%*(LL s ) / L sWhen ∆L is within the range of ±2%, that is, ∆L∈[-2%, 2%], the measurement result of the sampling flow of the device under evaluation is considered accurate; otherwise, the measurement result is considered inaccurate. When the measurement result is inaccurate, a single-point calibration is used, that is, the difference is increased or decreased by the same amount.

[0062] Preferably, the range of the standard flow meter is (0-20) L / min. It is often used to test PM 2.5 The accuracy of the sampling flow rate of the mass concentration monitoring equipment is 16.7L / min, which is the operating flow rate.

[0063] The temperature and humidity generating device 2 includes an air inlet end 21, a mixing chamber 22 and an air pump 23. A first air path 211 and a second air path 212 are provided in parallel between the air inlet end 21 and the mixing chamber 22, that is, the air inlet end 21 and the mixing chamber 22 can be connected through the first air path 201 and the second air path 202 respectively, that is, one end of the first air path 201 is connected to the air inlet end 21, the other end of the first air path 211 is connected to the mixing chamber 22, one end of the second air path 202 is connected to the air inlet end 21, and the other end of the second air path 202 is connected to the mixing chamber 22.

[0064] The first air path 201 is equipped with a water reservoir 24 to convert the gas entering the first air path into humidified moisture, which is then directed into the mixing chamber. In other words, the water reservoir 24 is located directly on the path of the first air path 201. The water reservoir 24 has a water storage chamber, the inlet and outlet of which are both connected to the first air path, meaning the water storage chamber is directly on the path of the first air path. The water storage chamber stores distilled water (i.e., pure water), and the gas from the first air path flows through the water storage chamber, removing water vapor and converting it into moisture.

[0065] Preferably, the inlet of the water reservoir 24 is located at the bottom of the water storage cavity, and the outlet of the water reservoir 24 is located at the top of the water storage cavity. On the one hand, it ensures that the air flow passes through the distilled water, and on the other hand, it ensures that the moisture is quickly and smoothly discharged from the water reservoir 24.

[0066] The second air path 202 introduces air or dried air into the mixing chamber; when the introduced air is dried air, the second air path is provided with a dryer 25, which must convert the gas entering the second air path into dry air to remove water vapor in the air entering the second air path, so as to better control the humidity in the mixing chamber. The dryer 25 is located on the necessary path of the second air path 202.

[0067] The air pump 23 is configured to allow external air to enter the temperature and humidity generating device 2 from the air inlet end 21 , and the air pump 23 is a negative pressure air pump.

[0068] The mixing chamber 22 is provided with a mixing cavity, which is in communication with the first gas path 201 and the second gas path 202 so as to mix the fluid introduced from the first gas path and the second gas path.

[0069] The mixing chamber 22 is further provided with a heater (not shown) and a standard thermo-hygrometer 221. The heater is configured to heat the fluid in the mixing chamber to a preset temperature. The standard thermo-hygrometer 221 is configured to test the temperature and humidity of the fluid in the mixing chamber. The measured temperature and humidity are the standard temperature T s and standard humidity H s Preferably, the probe of the standard thermometer and hygrometer 221 is inserted into the mixing chamber, and the reading part of the standard thermometer and hygrometer 221 is located outside the mixing chamber 22 to facilitate reading the standard temperature T s and standard humidity H s .

[0070] In order to accurately control the humidity of the gas in the mixing chamber, the first gas path 201 is provided with a first flow controller (not shown in the figure), and the first flow controller is configured to at least control the flow rate of the fluid entering the mixing chamber through the first gas path. The second gas path 202 is provided with a second flow controller (not shown in the figure), and the second flow controller is configured to at least control the flow rate of the fluid entering the mixing chamber through the second gas path. The humidity in the mixing chamber is controlled by controlling the volume ratio of the gas introduced into the mixing chamber by the first gas path and the second gas path. For example, when the standard humidity H s When the humidity is lower than the preset value, the humidity ratio of the first air path is increased until the standard humidity Hs is equal to the preset value. s When the humidity is greater than the preset value, the proportion of gas introduced into the second gas path is increased until the standard humidity H s Equal to the preset humidity.

[0071] Preferably, the standard thermometer and hygrometer, the first flow controller, the second flow controller, and the heater are intelligently controlled through an intelligent central control system so that the temperature and humidity in the mixing chamber quickly reach the preset temperature and humidity.

[0072] The thermometer and hygrometer or thermometer and hygrometer of the device to be evaluated is taken out and installed on the mixing chamber 22 to detect the temperature and humidity of the fluid in the mixing chamber. That is, the mixing chamber is provided with an assembly part that matches the thermometer and hygrometer or thermometer and hygrometer of the device to be evaluated. The probe of the thermometer and hygrometer or thermometer and hygrometer can be extended into the mixing chamber, and similarly, its reading part is also located outside the mixing chamber. The temperature and humidity data of the mixing chamber measured by the thermometer and hygrometer or thermometer and hygrometer of the device to be evaluated are the measured temperature T and the measured humidity H. The difference between the temperature measurement value and the standard value △T=TT s , the difference between the humidity measurement value and the standard value △H=HH s .

[0073] To determine the humidity measurement accuracy of the device under evaluation, the temperature in the mixing chamber is first controlled to a preset temperature (e.g., 20°C). The humidity in the mixing chamber is then sequentially controlled to a preset series of humidity levels (e.g., 20%RH, 35%RH, 60%RH, and 80%RH). The standard humidity and measured humidity at each preset humidity level are recorded. If the delta H at each preset humidity level is within the ±2%RH range, i.e., delta H∈[-2%RH, 2%RH], the humidity measurement result of the device under evaluation is considered accurate. Otherwise, the measurement result is considered inaccurate. If the measurement result is inaccurate, a linear fitting method is used to correct the measured humidity to the standard humidity to improve the humidity measurement accuracy of the device under evaluation.

[0074] To determine the accuracy of the temperature measurement of the device under evaluation, the humidity in the mixing chamber is first controlled to a preset humidity (e.g., 20% RH). The temperature of the mixing chamber is then sequentially controlled to a preset series of temperatures (e.g., 0°C, 10°C, 20°C, and 40°C). The standard temperature and the measured temperature at each preset temperature are recorded. If the delta T at each preset humidity is within the ±1°C range, i.e., delta T∈[-1°C, 1°C], the temperature measurement result of the device under evaluation is considered accurate. Otherwise, the measurement result is considered inaccurate. If the measurement result is inaccurate, a linear fitting method is used to correct the measured temperature to the standard temperature to improve the temperature measurement accuracy of the device under evaluation.

[0075] The temperature and humidity generating device of the utility model can be integrated in a relatively small housing and can be taken to the field for operation at any time, which is more portable and improves its use effect.

[0076] The particle generating device 3 includes a gas supply assembly 31, a liquid supply assembly 32, and an atomizing assembly 33. The atomizing assembly 33 is in communication with the gas supply assembly 31 and the liquid supply assembly 32, respectively. The gas supply assembly 31 is configured to provide a fixed amount of clean gas to the atomizing assembly 33. The liquid supply assembly 32 is configured to provide a fixed amount of liquid to the atomizing assembly 33. The atomizing assembly 33 is configured to mix the gas provided by the gas supply assembly 31 with the liquid provided by the liquid supply assembly 32 to form a particle fluid.

[0077] Specifically, the gas supply component 31 includes a connected air compressor 311 and a filter 312. The air compressor 311 is configured to convert external air into compressed air and to measure the flow rate of the compressed air. The filter 312 is configured to remove impurities in the compressed air. The impurities refer to substances with a certain particle size, such as moisture, sulfur dioxide, etc., that is, the particulate matter originally present in the air and not generated by the particle generating device are all impurities. The inlet of the filter 312 is connected to the air compressor 311, and the outlet of the filter 311 is connected to the air inlet 33a of the atomizing component 33, so as to provide the filtered compressed air to the atomizing component 33.

[0078] The flow rate of air entering the atomizing assembly 33 after being filtered by the filter element 312 is V, which is measured by the air compressor 311.

[0079] The liquid supply component 32 includes a connected liquid reservoir 321 and a syringe pump 322. The liquid reservoir 321 is configured to store the liquid provided to the atomization component 33. The liquid is a salt solution. The salt solution has the advantages of stable properties and uniform concentration, can stably produce particulate matter gas, and has good repeatability. Preferably, the liquid is a sodium chloride solution, a potassium chloride solution or other inorganic salt solution, and the concentration c of the salt solution is known. The syringe pump 322 is configured to provide the liquid to the atomization component 33 in a quantitative manner. Preferably, the liquid supply component 32 includes a plurality of syringe pumps 322, and the plurality of syringe pumps 322 are connected to the liquid reservoir in parallel. When the number of syringe pumps is multiple, the liquid extracted by the multiple syringe pumps is collected at the same place and then introduced into the atomization component 33 together. The liquid flow rate introduced into the atomization component 33 by the syringe pump is Q, which is measured by the syringe pump.

[0080] The atomizing assembly 33 includes an atomizer 331 and a mixing chamber 332. The atomizer 331 is provided with a liquid inlet 33b that is connected to the liquid supply assembly 32. Specifically, the liquid inlet 33b is connected to the syringe pump 322 so that the syringe pump 322 can introduce the liquid extracted from the liquid outlet 321 into the atomizer. The atomizer 331 is configured to break up the liquid into droplets and introduce the droplets into the mixing chamber 132. The mixing chamber 332 is provided with an outlet 33c and an air inlet 33a that is connected to the gas supply assembly 31. After the droplets and the clean air are evenly mixed in the mixing chamber 332, they are guided out of the atomizing assembly 33 through the liquid outlet 33c.

[0081] The mass concentration δ (in μg / m3) of the particulate fluid derived from the liquid outlet 33c of the atomizing assembly 33 is calculated as follows:

[0082]

[0083] Wherein, V is the flow rate of clean air entering the atomizing assembly 33, in L / min; c is the concentration of the liquid entering the atomizing assembly 33, in g / L; Q is the flow rate of the liquid entering the atomizing assembly 33, in mL / h.

[0084] The particulate fluid derived from the liquid outlet 33c is introduced into the device to be evaluated 5 to detect the mass concentration, that is, the liquid outlet 33c of the particulate matter generating device 3 is connected to the sampling head of the device to be evaluated, and the generated particulate fluid with the marked concentration is introduced into the device to be evaluated to test the accuracy of the mass concentration measurement of the device to be evaluated. Inorganic salt solutions such as sodium chloride and potassium chloride are used to generate particulate gas, and the median particle size of the particulate gas can be less than 1μm. The mass concentration of the particulate fluid is controlled in sequence to the mass concentration under the preset series (such as 20μg / m 3 , 50 μg / m 3 , 100 μg / m 3 , 200 μg / m 3 ), and record the standard mass concentration C at each preset mass concentration s (ie δ) and the measured mass concentration C, if the measurement error at each preset mass concentration is △C=100%*(CC s ) / C s When △C is within the range of ±5%, that is, △C∈[-5%, 5%], the mass concentration measurement result of the device under evaluation is considered accurate; otherwise, the measurement result is considered inaccurate. If the measurement result is inaccurate, a linear fitting method is used to correct the measured mass concentration to the standard mass concentration to improve the accuracy of the mass concentration measurement of the device under evaluation.

[0085] Exemplarily, the device to be evaluated uses a beta-ray mass sensor to measure the mass of particulate matter, and converts the mass data into mass concentration data through sampling flow and sampling time.

[0086] It should be noted that the particulate fluid refers to a gas fluid containing particulate matter, and preferably, the gas is air.

[0087] The manual sampling device 4 includes a sampling pump, a flow control device, a standard membrane assembly and a weighing assembly. The flow controller and the sampling pump are configured to jointly control the flow of the particulate fluid reaching the standard filter membrane and simultaneously control the sampling time; the standard membrane assembly includes a standard filter membrane and a membrane support, and the standard filter membrane is mounted on the membrane support; the weighing assembly is configured to weigh the mass of the standard membrane assembly.

[0088] The material of the standard filter membrane is one of polytetrafluoroethylene filter membrane, quartz filter membrane, glass fiber filter membrane and the like.

[0089] Preferably, the particle load on the filter membrane should be no less than 50 times the calibration graduation value of the weighing device. For example, the mass of the particles collected on the standard filter membrane should be at least 0.5 mg.

[0090] It should be noted that the structures of the sampling pump, flow control device and standard filter membrane assembly themselves are not the innovations of the present invention. They all adopt existing technologies, and the existing technologies can achieve the functions required by both.

[0091] At the same time, the sampling switch of the device to be evaluated 5 and the switch of the manual sampling device 4 are turned on, and the mass concentration of the particulate matter in the outdoor environment is measured at the same time to verify the rationality of the dynamic heating program setting of the device to be evaluated. Specifically, the sampling frequency of the device to be evaluated is every 1 hour / time, and the sampling frequency of the manual sampling device is every 23 hours / time. The filter membrane of the manual sampling device 4 is replaced every 23 hours, and the difference in the mass of the standard filter membrane assembly before and after sampling is used as the test value of the manual sampling device 4. The average value of the 23-hour measurement data of the device to be evaluated in the same time period is the test value, which is compared with the test value of the manual sampling device. Collect more than 10 groups of data, calculate the comparison slope and intercept, and when the comparison slope is within the range of 1.0±0.1, the comparison intercept is within the range of ±5ppb, and the comparison linear relationship is greater than or equal to 0.95, it means that the dynamic heating program setting of the device to be evaluated is reasonable, otherwise it is unreasonable.

[0092] To improve the intelligent effect of the evaluation system of the present invention, the gas flow standard device 1, the temperature and humidity generating device 2, the particulate matter generating device 3, and the manual sampling device 4 are each provided with an intelligent evaluation module that cooperates therewith. That is, the intelligent evaluation module is logically configured to cooperate with the above-mentioned evaluation method. In this way, the intelligent evaluation module can directly obtain the accuracy of various data measurements of the device to be evaluated and the feasibility of setting the dynamic heating program. In addition, the gas flow standard device 1, the temperature and humidity generating device 2, and the particulate matter generating device 3 are also respectively provided with an intelligent calibration module that cooperates therewith. That is, the intelligent calibration module is logically configured to cooperate with the above-mentioned calibration method. In this way, the intelligent calibration module can calibrate inaccurate measurement data of the device to be evaluated to improve the accuracy of the device to be evaluated.

[0093] It should be noted that how to respectively set up the intelligent evaluation module and the intelligent calibration module through the above-mentioned evaluation method and calibration method logic belongs to the existing technology and is not the focus of protection of the present utility model.

[0094] The utility model fully considers the factors affecting the particulate matter mass concentration monitoring equipment. Through the calibration of mass concentration sensor, temperature and humidity sensor, gas flow sensor, and confirmation of dynamic heating program, the accuracy of the monitoring data of the particulate matter mass concentration monitoring equipment can be verified in all directions.

[0095] Compared with the method of using a standard temperature and humidity meter for single-point comparison to verify the temperature and humidity sensors of the particulate matter mass concentration monitoring equipment, the utility model uses a portable temperature and humidity generating device to generate ambient air with different temperatures and humidities on site in real time, and performs multi-point linear fitting to accurately calibrate the temperature and humidity sensors in the particulate matter mass concentration monitoring equipment.

[0096] Compared with the method of using ISO A1 dust to generate particulate matter gas, the use of a particulate matter generating device to generate particulate matter gas with an accurate mass concentration containing an inorganic salt solution has the characteristics of good stability and high accuracy. It also has a theoretical value of the particulate matter mass concentration and can directly calibrate the mass sensor in the particulate matter mass concentration monitoring equipment, making calibration convenient.

[0097] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any changes or replacements that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed in the present invention should be covered by the protection scope of the present invention.

Claims

1. An evaluation system for particulate matter mass concentration monitoring equipment, characterized in that: include: A gas flow standard device configured to at least determine whether the sampling flow of the device to be evaluated is accurate; A temperature and humidity generating device configured to at least generate a fluid with controllable temperature and humidity, so as to at least determine whether the temperature and humidity measurements of the device to be evaluated are accurate; a particle generating device configured to generate at least a particulate flow of controlled concentration to at least determine whether the mass concentration measurement of the device to be evaluated is accurate; The manual sampling device is configured to at least determine whether the dynamic heating unit of the device to be evaluated is reliable.

2. The evaluation system according to claim 1, wherein: The gas flow standard device includes a standard flow meter, which is configured to be detachably installed in a sampling channel of the device to be evaluated so as to be able to test the sampling flow in the sampling channel.

3. The evaluation system according to claim 1, wherein: The temperature and humidity generating device includes an air inlet end, a mixing chamber and an air pump; A first air path and a second air path connected in parallel are provided between the air inlet end and the mixing chamber; The first gas path is provided with a water reservoir to prepare the gas entering the first gas path to be converted into wet gas with humidity, and to guide the wet gas into the mixing chamber; The second air path introduces air or dried air into the mixing chamber; The air extraction pump is configured to allow external air to enter the temperature and humidity generating device from the air inlet end; The mixing chamber is provided with a mixing cavity, which is in communication with the first gas path and the second gas path, so as to mix the fluid introduced from the first gas path and the second gas path; The mixing chamber is further provided with a heater and a standard thermo-hygrometer. The heater is configured to heat the fluid in the mixing chamber to a preset temperature, and the standard thermo-hygrometer is configured to test the temperature and humidity of the fluid in the mixing chamber.

4. The evaluation system according to claim 3, wherein: The first gas path is provided with a first flow controller, and the first flow controller is configured to at least control the flow rate of the fluid entering the mixing chamber through the first gas path; The second gas path is provided with a second flow controller, and the second flow controller is configured to at least control the flow of the fluid entering the mixing chamber through the second gas path.

5. The evaluation system according to any one of claims 1 to 4, characterized in that: The particle generating device comprises a gas supply component, a liquid supply component and an atomizing component, wherein the atomizing component is communicated with the gas supply component and the liquid supply component respectively; The gas supply component is configured to provide a quantitative amount of clean gas to the atomization component; The liquid supply component is configured to provide a quantitative amount of liquid to the atomization component; The atomizing assembly is configured to mix and disperse the gas provided by the gas providing assembly and the liquid provided by the liquid providing assembly into a particulate fluid.

6. The evaluation system according to claim 5, characterized in that The gas supply assembly includes a connected air compressor and filter element; The air compressor is configured to convert external air into compressed air and to measure the flow rate of the compressed air; The filter element is configured to remove impurities from the compressed air; The inlet of the filter element is connected to the air compressor, and the outlet of the filter element is communicated with the air inlet of the atomizing assembly so as to provide the filtered compressed air to the atomizing assembly.

7. The evaluation system according to claim 5, characterized in that The liquid providing assembly includes a connected liquid reservoir and a syringe pump; The liquid reservoir is configured to store liquid provided to the atomizing assembly; The syringe pump is configured to provide the liquid to the nebulizer assembly in a quantitative manner.

8. The evaluation system according to claim 7, characterized in that The liquid supply assembly includes a plurality of injection pumps, which are connected to the liquid reservoir in parallel.

9. The evaluation system according to claim 5, wherein: The atomization assembly includes an atomizer and a mixing chamber; The atomizer is provided with a liquid inlet in communication with the liquid supply assembly, and the atomizer is configured to break up the liquid into droplets and introduce the droplets into the mixing chamber; The mixing chamber is provided with an outlet and an air inlet connected to the gas supply assembly. After the liquid droplets and the gas are evenly mixed in the mixing chamber, they are guided out of the atomization assembly through the outlet.

10. The evaluation system according to claim 1, wherein: The manual sampling device includes a sampling pump, a flow control device, a standard membrane component and a weighing component; The standard membrane assembly includes a standard filter membrane and a membrane support, and the standard filter membrane is mounted on the membrane support; The flow control device and the sampling pump are configured to jointly control the flow of the particulate fluid reaching the standard filter membrane and simultaneously control the sampling time; The weighing assembly is configured to be able to weigh the mass of the standard membrane assembly.

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