An experimental device for black carbon aging research

Abstract

The present application relates to the technical field of black carbon aging research, and particularly relates to an experimental device for black carbon aging research, which comprises: a sample feeding system, the sample feeding system comprising a heating pipe, a pretreatment pipe, an oxidizing gas removal pipe and a drying pipe connected in series; a black carbon wrapping device, the black carbon wrapping device comprising an injection assembly, a wrapping chamber, a first absorption chamber, a heating removal assembly and a second absorption chamber connected in sequence; a detection system, the detection system being connected to the first absorption chamber, the heating removal assembly and the second absorption chamber; an integrated device, the integrated device comprising a mounting box and an aerosol charging device, a first differential migration particle size analyzer, a second differential migration particle size analyzer and a condensed particle counter arranged in the mounting box; and a control system, the control system being arranged in the mounting box and used to regulate and control the sample feeding system, the black carbon wrapping device, the detection system and the integrated device. The present application improves the convenience of black carbon research.

Description

Technical Field

[0001] This invention relates to the field of black carbon aging research technology, and in particular to an experimental apparatus for black carbon aging research. Background Technology

[0002] Studies have shown that the morphology of black carbon is a crucial factor influencing its light absorption capacity, and may hold promise for resolving related debates. The microscopic morphological evolution of black carbon during aging processes (i.e., condensation, moisture absorption, evaporation, phase separation, etc.) is central to solving the scientific challenge of observed light absorption values ​​being lower than model estimates. However, current research lacks a clear understanding of the morphological evolution mechanisms of black carbon during different aging processes, and quantitative studies on the impact of deformation on light absorption are also lacking.

[0003] Currently, research on the mechanisms of black carbon encapsulation by different organic and inorganic substances, as well as the collapse and phase separation mechanisms of black carbon induced by humidified and aged black carbon, is relatively scarce. This is mainly due to the lack of stable simulation devices and methods. Domestically, there are no similar devices or research tools. Internationally, current simulations of black carbon aging mostly employ the method of directly evaporating a single organic substance in an encapsulation chamber to encapsulate fresh black carbon particles, lacking research platforms and methods for mixed encapsulation of organic and inorganic substances. Furthermore, direct evaporation makes it difficult to effectively control the concentration of organic vapors, hindering the accurate elucidation of the black carbon collapse mechanism and the establishment of a parameterized scheme for black carbon collapse after encapsulation by multiple organic and inorganic substances. Regarding phase separation mechanism research, due to the lack of suitable platforms and methods, while commercially available hygroscopic series differential electromobility analyzers (HTDMA) perform well in direct measurements of environmental receptors, they have shortcomings in comprehensively considering multiple treatment methods such as aerosol humidification, evaporation, and heating. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in related technologies. To this end, this invention provides an experimental apparatus for black carbon aging research, solving the technical problem of the lack of a stable simulation device for black carbon research in the prior art, and improving the convenience of black carbon research.

[0005] This invention provides an experimental apparatus for studying the aging of black carbon, comprising:

[0006] The sample introduction system includes a heating tube, a pretreatment tube, an oxidizing gas removal tube, and a drying tube connected in series.

[0007] A black carbon coating device, comprising an injection assembly, a coating chamber, a first absorption chamber, a heating removal assembly, and a second absorption chamber connected in sequence;

[0008] The detection system is connected to the first absorption chamber, the heating removal component, and the second absorption chamber;

[0009] An integrated device includes a mounting box and an aerosol charging device, a first differential migration particle size analyzer, a second differential migration particle size analyzer, and a condensed particulate matter counter disposed within the mounting box. The aerosol charging device is connected to the first differential migration particle size analyzer and disposed between the drying tube and the encapsulation chamber. The second differential migration particle size analyzer is connected to the condensed particulate matter counter and is connected to either the first absorption chamber or the second absorption chamber.

[0010] A control system is installed inside the mounting box and is used to regulate the sample introduction system, the black carbon coating device, the detection system, and the integrated device.

[0011] A further improvement of the experimental apparatus for studying black carbon aging in this invention is that a neutralizer controller is also provided inside the installation box, and the neutralizer controller is connected to the aerosol electrified device.

[0012] A further improvement of the experimental apparatus for studying black carbon aging in this invention is that a third temperature and humidity sensor is provided between the aerosol charging device and the first differential migration particle size analyzer.

[0013] A further improvement of the experimental apparatus for studying black carbon aging in this invention is that the installation box is further provided with a first gas differential pressure flow meter, a first filter and a first fan connected in sequence, and the first gas differential pressure flow meter and the first fan are connected to the first differential migration particle size analyzer.

[0014] A further improvement of the experimental apparatus for studying black carbon aging in this invention is that the installation box is further provided with a second gas differential pressure flow meter, a first temperature and humidity sensor, a second filter, a humidification pipe and a second fan connected in sequence, and the second gas differential pressure flow meter and the second fan are connected to the second differential migration particle size analyzer.

[0015] A further improvement of the experimental apparatus for studying the aging of black carbon according to the present invention is that the humidification tube has a first connection port and a second connection port, a second temperature and humidity sensor is provided between the first connection port and the second connection port, the second temperature and humidity sensor is connected to a mass flow controller, and the mass flow controller is connected to a nitrogen supply device.

[0016] A further improvement of the experimental apparatus for studying black carbon aging according to the present invention is that the mass flow controller has two components connected in parallel.

[0017] A further improvement of the experimental apparatus for studying black carbon aging in this invention is that a power supply is provided inside the installation box, the power supply is connected to the control system, and a temperature and humidity sensor communicator and a flow sensor communicator are connected in parallel between the power supply and the control system.

[0018] A further improvement of the experimental apparatus for studying black carbon aging in this invention is that the power supply is also connected to a communication chassis, the communication chassis is connected to the control system, and a first fan controller and a second fan controller are connected in parallel between the power supply and the communication chassis. The first fan controller is used to control the first fan, and the second fan controller is used to control the second fan.

[0019] A further improvement of the experimental apparatus for studying black carbon aging in this invention is that the communication chassis is connected to a first high-voltage module and a second high-voltage module arranged in parallel. The first high-voltage module is used to control the first differential migration particle size analyzer, and the second high-voltage module is used to control the second differential migration particle size analyzer.

[0020] The experimental apparatus of this invention integrates functional modules such as pretreatment of sample gas containing black carbon, charged screening of black carbon, encapsulation aging, multi-state detection, and system control into a single installation box, replacing the combination of traditional decentralized equipment. This saves experimental space, simplifies cross-equipment operation procedures, and reduces the labor and time costs of experiments. The sample introduction system can efficiently remove volatile impurities, oxidizing gases, moisture, and other interfering substances from the sample gas, achieving precise purification of the black carbon sample gas and avoiding interference from impurities on subsequent aging simulation and morphology detection results, thus improving the authenticity of experimental data. The black carbon encapsulation device supports multi-state processing of "encapsulation aging and heating to remove the encapsulation." Combined with the detection system to detect different stages such as "fresh black carbon, black carbon after encapsulation, and black carbon after heating to remove the encapsulation," it realizes the acquisition of full-process parameters of black carbon from its initial state to different aging degrees, overcoming the limitation of traditional devices that can only simulate a single aging state, and providing complete data support for the study of the morphological evolution mechanism of black carbon. By using an "aerosol charging device and a first differential migration particle size analyzer" to screen black carbon with specific electromigration particle sizes, and then using a "second differential migration particle size analyzer and a condensed particulate counter" to verify particle size consistency, the uniformity of experimental samples was ensured. This avoided the influence of particle size differences on the morphology and optical parameter detection results, improving the comparability and repeatability of experimental results. The control system can uniformly regulate key parameters such as temperature and flow rate of each module, reducing human operation errors, ensuring the stability of experimental conditions, and making experimental results reproducible for different batches and different operators.

[0021] Compared with the prior art, the present invention has the following advantages: (1) Adjustable voltage and delay time: The control system 2 supports the customization of key parameters such as the delay time and particle size scanning sequence between the first differential migration particle size analyzer 42 and the second differential migration particle size analyzer 51. The residence time of aerosol in the processing unit can be flexibly adjusted according to experimental needs to adapt to different detection scenarios (such as the switching between hygroscopic and evaporative processes); (2) Precise humidity control: The humidification tube 55 is combined with the temperature and humidity sensor to achieve stable control of different humidity environments. The mixing ratio of dry gas and moisture is precisely adjusted by the mass flow controller 58 to ensure the rapid response and stability of sheath gas humidity, thus solving the problem of large error of temperature and humidity sensor in high humidity environment; (3) The sample injection system can remove volatile substances and black carbon coating layers in different emissions, realize the separate analysis of pure black carbon particles, and solve the problem of interference of different complex components to detection; (4) The integrated aging and heating removal and hygroscopic system can realize the coating of black carbon with organic matter, inorganic matter or a mixture of the two at different concentrations, as well as measure the physical properties of aged black carbon after hygroscopic and heating volatilization.

[0022] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of an experimental apparatus for studying the aging of black carbon provided by the present invention. Figure 1 .

[0025] Figure 2 This is a schematic diagram of an experimental apparatus for studying the aging of black carbon provided by the present invention. Figure 2 .

[0026] Figure 3 This is a schematic diagram of an experimental apparatus for studying the aging of black carbon provided by the present invention. Figure 3 .

[0027] Figure 4 This is a time series plot of relative humidity.

[0028] Figure 5 This is a graph showing the relationship between the hygroscopic growth factor of ammonium sulfate particles and relative humidity.

[0029] Figure label:

[0030] 11. Heating tube; 12. Pretreatment tube; 13. Oxidizing gas removal tube; 14. Drying tube; 2. Control system; 31. Aerosol charging device; 32. Neutralizer controller; 41. Third temperature and humidity sensor; 42. First differential migration particle size analyzer; 43. First gas differential pressure flow meter; 44. First filter; 45. First fan; 51. Second differential migration particle size analyzer; 52. Second gas differential pressure flow meter; 53. First temperature and humidity sensor; 54. Second filter; 55. Humidification tube; 56. Second temperature and humidity sensor; 57. Humidity sensor; 58. Second fan; 59. Mass flow controller; 60. Condensed particulate matter counter; 61. Injection assembly; 62. Encapsulation chamber; 63. First absorption chamber; 64. Heating removal assembly; 65. Second absorption chamber; 7. Detection system; 8. Mounting box; 91. Temperature and humidity sensor communicator; 92. Flow sensor communicator; 101. Power supply; 111. First fan controller; 112. Second fan controller; 121. Communication chassis; 131. First high-voltage module; 132. Second high-voltage module. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. The following embodiments are used to illustrate this invention but should not be used to limit the scope of this invention.

[0032] The following is combined Figures 1 to 3 An experimental apparatus for studying the aging of black carbon, as described in this invention, includes:

[0033] The sample introduction system includes a heating tube 11, a pretreatment tube 12, an oxidizing gas removal tube 13, and a drying tube 14 connected in series.

[0034] A carbon coating device, comprising an injection assembly 61, a coating chamber 62, a first absorption chamber 63, a heating removal assembly 64, and a second absorption chamber 65 connected in sequence;

[0035] The detection system 7 is connected to the first absorption chamber 63, the heating removal component 64, and the second absorption chamber 65.

[0036] An integrated device includes a mounting box 8 and an aerosol charging device 31, a first differential migration particle size analyzer 42, a second differential migration particle size analyzer 51, and a condensed particulate matter counter 59 disposed within the mounting box 8. The aerosol charging device 31 and the first differential migration particle size analyzer 42 are connected and disposed between the drying tube 14 and the encapsulation chamber 62. The second differential migration particle size analyzer 51 is connected to the condensed particulate matter counter 59 and is connected to either the first absorption chamber 63 or the second absorption chamber 65.

[0037] Control system 2, which is located inside the mounting box 8, is used to regulate the sample introduction system, the black carbon coating device, the detection system 7, and the integrated device.

[0038] Preferably, the experimental apparatus of the present invention integrates functional modules such as pretreatment of sample gas containing black carbon, charged sieving of black carbon, encapsulation aging, multi-state detection, and system control into a single mounting box 8, replacing the combination of traditional decentralized equipment. This saves experimental space, simplifies cross-equipment operation procedures, and reduces the labor and time costs of experiments. The sample introduction system can efficiently remove volatile impurities, oxidizing gases, moisture, and other interfering substances from the sample gas, achieving precise purification of the black carbon sample gas and avoiding interference from impurities on subsequent aging simulation and morphology detection results, thus improving the authenticity of experimental data. The black carbon encapsulation device supports multi-state processing of "encapsulation aging and heating to remove the encapsulation." Combined with the detection system 7, which detects different stages such as "fresh black carbon, black carbon after encapsulation, and black carbon after heating to remove the encapsulation," it realizes the acquisition of parameters for the entire process of black carbon from its initial state to different aging degrees. This overcomes the limitation of traditional devices that can only simulate a single aging state and provides complete data support for the study of the morphological evolution mechanism of black carbon. Black carbon with specific electromigration particle sizes was screened using an "aerosol charging device 31 and a first differential migration particle size analyzer 42," and particle size consistency was verified using a "second differential migration particle size analyzer 51 and a condensed particulate counter 59." This ensured the uniformity of the experimental samples, avoided the influence of particle size differences on the morphology and optical parameter detection results, and improved the comparability and repeatability of the experimental results. The control system 2 can uniformly regulate key parameters such as temperature and flow rate of each module, reducing errors from manual operation, ensuring the stability of experimental conditions, and making the experimental results reproducible for different batches and different operators.

[0039] In a preferred embodiment of the experimental apparatus for studying black carbon aging according to the present invention, such as... Figures 1 to 3 As shown, the installation box 8 is also equipped with a neutralizer controller 32, which is connected to the aerosol electrified device 31.

[0040] Preferably, the neutralizer controller 32 can precisely adjust the operating parameters of the aerosol charging device 31 to ensure that the black carbon particles obtain a stable and controllable charge. Precise charge control ensures that black carbon particles of a specific size that meet experimental requirements can be accurately selected during the screening process of the aerosol charging device 31 and the first differential migration particle size analyzer 42. The neutralizer controller 32 has an automated monitoring and feedback mechanism, capable of monitoring the charging status of the black carbon particles within the aerosol charging device 31 in real time and adjusting the control signal promptly according to preset parameter requirements. If a deviation in charge is detected, the neutralizer controller 32 will quickly analyze the cause and, by fine-tuning relevant parameters such as applied voltage and gas flow rate, restore the charging state of the black carbon particles to the set value, thereby ensuring the stability of the entire experimental process. The neutralizer controller 32 also has data recording and storage functions, capable of recording the operating status and parameter changes of the aerosol charging device 31 during each experiment. This data can provide important evidence for subsequent experimental analysis and result verification. By analyzing a large amount of experimental data, the control strategy of the neutralizer controller 32 can be further optimized, and the control accuracy of the aerosol charging device 31 can be improved, thereby providing more reliable experimental conditions for black carbon aging research.

[0041] Furthermore, a third temperature and humidity sensor 41 is installed between the aerosol charging device 31 and the first differential migration particle size analyzer 42. This third temperature and humidity sensor 41 can monitor the temperature and humidity of the aerosol in real time during the transfer from the aerosol charging device 31 to the first differential migration particle size analyzer 42. Temperature and humidity have a significant impact on the physical properties and charged state of black carbon particles. Different temperature and humidity conditions may cause changes in the degree of aggregation and surface charge distribution of black carbon particles. The accurate temperature and humidity data obtained by the third temperature and humidity sensor 41 can provide an important reference for subsequent experimental analysis. Experimenters can make corresponding adjustments to the experimental environment based on the temperature and humidity information fed back by the third temperature and humidity sensor 41. If the temperature is too high or too low, it may affect the charged stability of the black carbon particles. In this case, the temperature can be maintained within a suitable range by adjusting the heating tube 11 of the experimental device. Similarly, if the humidity does not meet the experimental requirements, corresponding changes can be made to the pretreatment tube 12 and drying tube 14 to implement dehumidification or humidification measures. This ensures that the temperature and humidity environment of the black carbon particles is stable and meets the experimental expectations when they enter the first differential migration particle size analyzer 42, thereby improving the accuracy and reliability of the experimental results. The temperature and humidity data recorded by the third temperature and humidity sensor 41 can also be combined with other experimental data recorded by the neutralizer controller 32 for more comprehensive and in-depth data analysis, providing richer experimental evidence for black carbon aging research.

[0042] Furthermore, the installation box 8 is also equipped with a first gas differential pressure flow meter 43, a first filter 44 and a first fan 45 connected in sequence, and the first gas differential pressure flow meter 43 and the first fan 45 are connected to the first differential migration particle size analyzer 42.

[0043] Preferably, the first gas differential pressure flow meter 43 can accurately measure the gas flow rate entering the first differential migration particle size analyzer 42, providing precise flow data for the experiment. The first filter 44 acts as a filter, effectively removing impurities from the gas in the first differential migration particle size analyzer 42 and preventing impurities from interfering with the experimental results. The first fan 45 provides power for the gas flow, ensuring that the gas flows stably through the first gas differential pressure flow meter 43 and the first filter 44 according to the set flow rate and direction, and finally enters the first differential migration particle size analyzer 42. During the experiment, the gas flow rate can be controlled by adjusting the power of the first fan 45, thereby meeting the gas flow rate requirements under different experimental conditions. The first gas differential pressure flow meter 43 monitors changes in gas flow rate in real time. Once abnormal fluctuations in flow rate are detected, it can promptly provide feedback to the experimenters, who can then adjust the first fan 45 accordingly to ensure the stability and accuracy of the experiment. The coordinated operation of the first gas differential pressure flow meter 43, the first filter 44 and the first fan 45 can construct a stable gas delivery and processing system, providing a stable and pure gas environment for the first differential migration particle size analyzer 42, and further improving the reliability and repeatability of experimental results.

[0044] Furthermore, the installation box 8 is also equipped with a second gas differential pressure flow meter 52, a first temperature and humidity sensor 53, a second filter 54, a humidification pipe 55 and a second fan 57 connected in sequence. The second gas differential pressure flow meter 52 and the second fan 57 are connected to the second differential migration particle size analyzer 51.

[0045] Preferably, the second gas differential pressure flow meter 52 monitors the gas flow rate in real time, providing data feedback for the entire gas delivery system. The first temperature and humidity sensor 53 detects the temperature and humidity of the gas. The second filter 54 purifies the gas, ensuring that the gas entering subsequent equipment is purer, reducing the interference of impurities on experimental results, and improving the reliability of the experiment. The humidification tube 55 can humidify the gas according to experimental requirements. In black carbon aging research, an appropriate humidity environment helps to simulate real atmospheric conditions, making the experimental results more representative. By adjusting the humidification amount of the humidification tube 55, the humidity of the gas can be precisely controlled to meet the requirements of different experimental conditions. The second fan 57 provides power for the gas flow, ensuring that the gas can smoothly pass through the second gas differential pressure flow meter 52, the first temperature and humidity sensor 53, the second filter 54, and the humidification tube 55 in sequence, and finally enter the second differential migration particle size analyzer 51.

[0046] Specifically, the humidification pipe 55 has a first connection port and a second connection port. A second temperature and humidity sensor 56 is provided between the first connection port and the second connection port. The second temperature and humidity sensor 56 is connected to a mass flow controller 58. There are two mass flow controllers 58 arranged in parallel. The mass flow controllers 58 are connected to a nitrogen supply device.

[0047] The second temperature and humidity sensor 56 can monitor the temperature and humidity of the gas inside the humidification tube 55 in real time, providing accurate data for subsequent gas regulation. Two parallel mass flow controllers 58 control the flow rate of nitrogen from the nitrogen supply device into the humidification tube 55. Nitrogen, as the carrier gas, provides a stable environment for gas delivery and also dilutes and protects the gas, preventing oxidation and other chemical reactions during transport, thus ensuring the stability and purity of the experimental gas. The mass flow controllers 58 can dynamically adjust the nitrogen flow rate based on the data from the second temperature and humidity sensor 56, achieving precise control of the gas composition and state within the humidification tube 55. When a specific gas environment is required for the experiment, the mass flow controllers 58 can respond quickly and accurately deliver an appropriate amount of nitrogen to mix with other gases, thereby meeting the requirements for gas composition and proportion under different experimental conditions, further improving the accuracy and reliability of the experimental setup in black carbon aging research.

[0048] Furthermore, such as Figure 3As shown, a power supply 101 is installed inside the mounting box 8. The power supply 101 is connected to the control system 2. A temperature and humidity sensor communicator 91 and a flow sensor communicator 92 are connected in parallel between the power supply 101 and the control system 2. The power supply 101 is also connected to a communication chassis 121, which is connected to the control system 2. A first fan controller 111 and a second fan controller 112 are connected in parallel between the power supply 101 and the communication chassis 121. The first fan controller 111 controls the first fan 45, and the second fan controller 112 controls the second fan 57. A first high-voltage module 131 and a second high-voltage module 132 are connected in parallel to the communication chassis 121. The first high-voltage module 131 controls the first differential migration particle size analyzer 42, and the second high-voltage module 132 controls the second differential migration particle size analyzer 51.

[0049] Preferably, the temperature and humidity sensor communicator 91 and the flow sensor communicator 92 are connected to the power supply 101 and the control system 2, enabling real-time and stable transmission of temperature, humidity, and gas flow data during the experiment. This allows the control system 2 to promptly capture parameter fluctuations and make rapid adjustments, ensuring accurate matching of experimental conditions with preset values ​​and avoiding experimental errors caused by data delays. The first fan controller 111 and the second fan controller 112 are connected in parallel, as are the first high-voltage module 131 and the second high-voltage module 132. This allows the first fan 45 and the second fan 57, and the first differential migration particle size analyzer 42 and the second differential migration particle size analyzer 51, to be independently controlled without interference, improving the flexibility and stability of parameter adjustment in different experimental stages. The power supply 101 provides stable power support for the control system 2, sensor communicators, and other components. Furthermore, the communication chassis 121 enables efficient data interaction between the control system 2 and the high-voltage modules, reducing line signal interference, improving the overall coordination and reliability of the device, and lowering the risk of equipment failure.

[0050] Preferably, the injection component 61 can inject either organic vapor or inorganic vapor. The organic vapor is typically chosen to simulate the organic components actually encapsulated by black carbon in the atmosphere, such as dimethyl phthalate (DMP), dibutyl phthalate (DBP), oleic acid, methyl palmitate, or α-pinene oxidation product vapor. The inorganic vapor can be selected from sulfuric acid vapor, nitric acid vapor, or hydrochloric acid vapor.

[0051] Preferably, for the sample introduction system, the outer layer of the heating tube 11 is a heating jacket, and the inner layer is a stainless steel tube; the outer layer of the pretreatment tube 12 is an acrylic tube, and the inner layer is a stainless steel mesh, with silica gel desiccant and activated carbon placed between the outer and inner layers of the pretreatment tube 12; the outer layer of the oxidizing gas removal tube 13 is an acrylic tube, and the inner layer is a stainless steel mesh, with potassium permanganate particles placed between the outer and inner layers of the oxidizing gas removal tube 13; the outer layer of the drying tube 14 is an acrylic tube, and the inner layer is a stainless steel mesh, with silica gel desiccant placed between the outer and inner layers of the drying tube 14.

[0052] Preferably, the mounting box 8 is a cubic non-sealed box, and the mounting box 8 includes a main frame, which includes an aluminum profile frame, a composite plate and a stainless steel plate.

[0053] In one specific implementation, the black carbon coating device injects organic vapor through injection component 61. The organic vapor and sample gas enter the coating chamber 62 together. The outer layer of the coating chamber 62 is a heating jacket and the inner layer is a stainless steel tube. The outer layer of the first absorption chamber 63 or the second absorption chamber 65 is an acrylic tube and the inner layer is a stainless steel mesh. Activated carbon is embedded between the outer and inner layers of the first absorption chamber 63 or the second absorption chamber 65. The outer layer of the heating removal component 64 is a heating jacket and the inner layer is a stainless steel tube.

[0054] Preferably, the first high-voltage module 131 and the second high-voltage module 132 are fixed on the bottom stainless steel plate of the mounting box 8. The first high-voltage module 131 and the second high-voltage module 132 establish communication with the control system 2 through the communication chassis 121 to control the voltage changes of the first differential migration particle size analyzer 42 and the second differential migration particle size analyzer 51. The communication chassis 121 is fixed on the bottom stainless steel plate of the mounting box 8. The first fan controller 111 and the second fan controller 112 are fixed on the composite plate of the mounting box 8 to control the speed changes of the first fan 45 and the second fan 57. The flow sensor communicator 92 and the temperature and humidity sensor communicator 91 are fixed on the composite plate of the mounting box 8. The control system 2 reads the data from the flow sensor communicator 92 and the temperature and humidity sensor communicator 91.

[0055] In one specific implementation example, the following operational steps are included:

[0056] S1. Sample Gas Collection: The sample gas needs to have a sufficient concentration of black carbon (greater than 3000 carbon atoms / cc), and the black carbon needs to be as fresh as possible to ensure a sufficiently low density (density less than 0.6 g / cm³). 3 (morphology factor greater than 1.5).

[0057] S2. Adjust the heating tube 11, the encapsulation chamber 62, and the heating removal component 64 to 400°C, and purge with pure nitrogen for 1 hour to remove residual organic matter inside the heating tube 11, the encapsulation chamber 62, and the heating removal component 64; dry the desiccant at 120°C for 1 hour, and wipe the inside of the first differential migration particle size analyzer 42 and the second differential migration particle size analyzer 51 with alcohol.

[0058] S3. Connect each component through the pipeline and test the flow rate at the sample gas inlet. If the flow rate is consistent with that of the condensed particulate matter counter, it indicates that the pipeline is airtight.

[0059] S4. Set the heating tube 11 and heating removal assembly 64 to 400°C, and set the temperature of the wrapping chamber 62 to the set temperature.

[0060] S5. Turn on the aerosol charging device 31 and neutralizer controller 32, turn on the control system 2, open the sheath gas control program in the control system 2, control the sheath gas flow rate to the set value, the sheath gas flow rate and sample gas flow rate are 10:1, turn on the condensed particulate matter counter 59.

[0061] S6. Sample gas is continuously collected. The sample gas passes through the sample introduction system, aerosol charging device 31, and first differential migration particle size analyzer 42 to screen black carbon particles with specific electromigration particle sizes. It then enters the second differential migration particle size analyzer 51 to verify the consistency of the migration particle size analyzer and enters the detection system 7 to determine the mass, optical, mixed state and other properties of fresh black carbon.

[0062] S7. Organic vapor is introduced into the encapsulation chamber 62, and sample gas is continuously collected. The sample gas passes through the sample introduction system, aerosol charging device 31, and first differential migration particle size analyzer 42 to screen black carbon particles with specific electromigration particle sizes before entering the encapsulation chamber 62.

[0063] S8. Pass the coated black carbon into the second differential migration particle size analyzer 51 to measure the change in electromigration particle size, and pass the coated black carbon into the detection system 7 to measure the mass, optical properties, mixed state, single particle morphology and other properties of the aged black carbon.

[0064] S9. Pass the coated black carbon into the heating tube 11 and the first absorption chamber 63 or the second absorption chamber 65, and then pass it into the second differential migration particle size analyzer 51 to measure the change in electromigration particle size. Pass the coated black carbon into the detection system 7 to measure the mass, optical properties, mixed state, single particle morphology and other properties of the black carbon after heating to remove the coating layer.

[0065] S10. Adjust the mass flow controller 58 to control the humidification gas of a certain humidity to enter the humidification tube 55, and wait for the humidification gas to humidify the sheath gas of the second differential migration particle size analyzer 51 to the set value of 55%~90%;

[0066] S11. After the sheath gas of the second differential migration particle size analyzer 51 reaches the set humidity, the wrapped black carbon is passed into the second differential migration particle size analyzer 51 to measure the change in electromigration particle size. After being passed into the second differential migration particle size analyzer 51, it enters the detection system 7 to measure the mass, optical properties, mixed state, single particle morphology and other properties of the aged black carbon after humidification.

[0067] S12. Calculate the morphology factor, density, optical parameters, and other physical properties of fresh black carbon, aged black carbon, aged black carbon removed by heating, and aged black carbon after humidification.

[0068] Preferably, the mass flow controller 58 has two components: a dry gas mass flow controller and a wet gas mass flow controller. Adjusting the ratio of the dry gas mass flow controller and the wet gas mass flow controller controls the humidification of gas with a certain humidity level into the humidification pipe 55. The humidification gas then humidifies the sheath gas of the second differential migration particle size analyzer 51 to a set value, which is 55%, 60%, 65%, 70%, 75%, 77%, 80%, 83%, or 90%. Figure 4 As shown, the humidifier tube 55 reaches the set humidity and can maintain it for a relatively long time with an error of ±0.5%.

[0069] Preferably, ammonium sulfate particles are collected as sample gas and sequentially passed through the sample introduction system, aerosol charging device 31, and first differential migration particle size analyzer 42 to screen ammonium sulfate particles with an electromigration diameter of 100 nm before entering a humidified second differential migration particle size analyzer 51. The particle size D after dilution is measured, and the hygroscopic growth factor is calculated. The hygroscopic growth factor = D / 100. The hygroscopic growth factor of ammonium sulfate particles changes with humidity as follows: Figure 5 As shown, the particle size increase at a relative humidity of 75%~77% is consistent with existing studies, proving the reliability of the humidification device, sieving device, and scanning device.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An experimental apparatus for studying the aging of black carbon, characterized in that, include: The sample introduction system includes a heating tube, a pretreatment tube, an oxidizing gas removal tube, and a drying tube connected in series. A black carbon coating device, comprising an injection assembly, a coating chamber, a first absorption chamber, a heating removal assembly, and a second absorption chamber connected in sequence; The detection system is connected to the first absorption chamber, the heating removal component, and the second absorption chamber; An integrated device includes a mounting box and an aerosol charging device, a first differential migration particle size analyzer, a second differential migration particle size analyzer, and a condensed particulate matter counter disposed within the mounting box. The aerosol charging device is connected to the first differential migration particle size analyzer and disposed between the drying tube and the encapsulation chamber. The second differential migration particle size analyzer is connected to the condensed particulate matter counter and is connected to either the first absorption chamber or the second absorption chamber. A control system is installed inside the mounting box and is used to regulate the sample introduction system, the black carbon coating device, the detection system, and the integrated device.

2. The experimental apparatus for studying black carbon aging according to claim 1, characterized in that, The installation box is also equipped with a neutralizer controller, which controls the connection to the aerosol electrified device.

3. The experimental apparatus for studying black carbon aging according to claim 1, characterized in that, A third temperature and humidity sensor is installed between the aerosol charging device and the first differential migration particle size analyzer.

4. The experimental apparatus for studying black carbon aging according to claim 3, characterized in that, The installation box is also equipped with a first gas differential pressure flow meter, a first filter and a first fan connected in sequence. The first gas differential pressure flow meter and the first fan are connected to the first differential migration particle size analyzer.

5. The experimental apparatus for studying black carbon aging according to claim 4, characterized in that, The installation box is also equipped with a second gas differential pressure flow meter, a first temperature and humidity sensor, a second filter, a humidification pipe and a second fan connected in sequence. The second gas differential pressure flow meter and the second fan are connected to the second differential migration particle size analyzer.

6. The experimental apparatus for studying black carbon aging according to claim 5, characterized in that, The humidification pipe has a first connection port and a second connection port. A second temperature and humidity sensor is provided between the first connection port and the second connection port. The second temperature and humidity sensor is connected to a mass flow controller, which is connected to a nitrogen supply device.

7. The experimental apparatus for studying black carbon aging according to claim 6, characterized in that, The mass flow controller has two units connected in parallel.

8. An experimental apparatus for studying the aging of black carbon according to claim 6, characterized in that, The installation box contains a power supply, which is connected to the control system. A temperature and humidity sensor communicator and a flow sensor communicator are connected in parallel between the power supply and the control system.

9. An experimental apparatus for studying the aging of black carbon according to claim 8, characterized in that, The power supply is also connected to a communication chassis, which is connected to the control system. A first fan controller and a second fan controller are connected in parallel between the power supply and the communication chassis. The first fan controller is used to control the first fan, and the second fan controller is used to control the second fan.

10. An experimental apparatus for studying the aging of black carbon according to claim 9, characterized in that, The communication chassis is connected to a first high-voltage module and a second high-voltage module arranged in parallel. The first high-voltage module is used to control the first differential migration particle size analyzer, and the second high-voltage module is used to control the second differential migration particle size analyzer.

Images