Portable detection and analysis device for condensable particulate matters of stationary pollution source

Abstract

The invention discloses a portable detection and analysis device for condensable particles of a stationary pollution source. The portable detection and analysis device comprises a sampling gun unit, a pretreatment unit, an analysis unit and a sampling unit, the sampling gun unit comprises a sampling nozzle, a pitot tube, a smoke temperature sensor, a sampling tube, a heating thermal insulation sleeve and a temperature controller; the pretreatment unit comprises a particulate matter cutter, a condensation pipe, a semiconductor refrigerator, a condensed water storage device, a quantitative peristaltic pump and a condensed water emptying pipe; the analysis unit comprises a sampling diaphragm, a closed heating device, a beta ray source and a ray detector; the sampling unit comprises a drying device, a metering device and a sampling pump. The in-situ rapid detection of the condensable particulate matters is realized, the detection efficiency is improved, the homogeneous and heterogeneous nucleation of the condensable particulate matters is effectively ensured, and the data accuracy is improved; connection is rapid, carrying is convenient, operation is easy, and compared with an existing manual monitoring method, the sampling speed is increased, and follow-up analysis time is shortened.

Description

Technical Field

[0001] This invention relates to the field of atmospheric pollution monitoring technology, and in particular to a portable detection and analysis device for condensable particulate matter from stationary pollution sources. Background Technology

[0002] Currently, the collection of condensable particulate matter in flue gas from stationary pollution sources mainly relies on the EPA M202 standard method. However, this traditional sampling scheme has many technical problems in practical applications. The core issue lies in the low degree of equipment integration, resulting in a severe lack of portability. The sampling system consists of multiple dispersed components such as a smoke gun, condenser tube, four absorption bottles, and filters, supplemented by external equipment such as an ice bath and circulating water bath. The overall system is bulky and the piping is complex. For industrial flue gas outlets, which are usually located at high altitudes, on-site transportation and installation are quite difficult.

[0003] Furthermore, the on-site operation procedures are quite cumbersome. From solution preparation before sampling to solution collection and processing after sampling, and repeated cleaning of multiple absorption bottles, each step increases the operation time. More importantly, the core requirement of temperature control is difficult to meet. The standard stipulates that the CPM filter and the front-end absorption bottle must be maintained at a constant temperature of 30°C, but the temperature control effect of existing equipment is poor and easily affected by external environmental interference, requiring constant manual adjustments and making it difficult to ensure stable sampling conditions. Finally, the complex subsequent analysis process and analysis cycle, coupled with unavoidable manual operation, further increase the risk of data errors and affect the final quality of the monitoring results. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a portable detection and analysis device for condensable particulate matter from stationary pollution sources.

[0005] To provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended as a general commentary, nor is it intended to identify key / important components or to describe the scope of protection of these embodiments. Its sole purpose is to present some concepts in a simple form as a prelude to the detailed description that follows.

[0006] The present invention adopts the following technical solution: This invention provides a portable detection and analysis device for condensable particulate matter from stationary pollution sources, comprising: a pretreatment unit and an analysis unit; the analysis unit includes: a sampling membrane and a sealed heating device for supporting the sampling membrane; the pretreatment unit includes: a particulate matter cutter, a condenser tube, a thermoelectric cooler, a condensate storage device, and a quantitative peristaltic pump, wherein the thermoelectric cooler is disposed on the outer wall of the condenser tube, the particulate matter cutter, the condenser tube, and the condensate storage device are sequentially connected, the upper section of the condensate storage device is connected to the sealed heating device through a flue gas path, the lower section of the condensate storage device is connected to the sealed heating device through a condensate dripping pipeline, and the quantitative peristaltic pump is disposed on the condensate dripping pipeline.

[0007] Furthermore, the analysis unit also includes a beta-ray source and a radiation detector, wherein the beta-ray source and the radiation detector are spaced apart by a certain distance to form an analysis position for placing the sampling membrane.

[0008] Furthermore, the pretreatment unit also includes: a condensate drain pipe connected to the condensate dripping pipe; and a condensate drain port is provided at the bottom of the condensate storage device.

[0009] Furthermore, the portable detection and analysis device for condensable particulate matter from stationary pollution sources further includes: a sampling unit; the sampling unit includes: a drying device, a metering device, and a sampling pump, the drying device being connected to the sealed heating device, the metering device being connected to the drying device, and the sampling pump being connected to the metering device.

[0010] Furthermore, the portable detection and analysis device for condensable particulate matter from stationary pollution sources further includes: a sampling gun unit; the sampling gun unit includes: a sampling nozzle, a Pitot tube, a smoke temperature sensor, and a sampling tube; the sampling nozzle, the Pitot tube, and the smoke temperature sensor are disposed on the exhaust gas conveying pipeline, one end of the sampling tube is connected to the sampling nozzle, and the other end of the sampling tube is connected to the particulate matter cutter.

[0011] Furthermore, the sampling gun unit also includes a heating and insulation sleeve and a temperature controller; the heating and insulation sleeve is disposed on the outer wall of the sampling tube, and the temperature controller is connected to the heating and insulation sleeve.

[0012] The beneficial effects of this invention are as follows: by integrating the β-ray method into the analysis unit, in-situ rapid detection of condensable particulate matter is achieved, improving detection efficiency; compared with other portable or online methods, the two-step collection measure can effectively ensure the homogeneous and heterogeneous nucleation of condensable particulate matter, improving data accuracy; it is quick to connect, easy to carry, and simple to operate, greatly improving sampling speed and reducing subsequent analysis time compared with existing manual monitoring methods. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram of a portable detection and analysis device for condensable particulate matter from stationary pollution sources according to the present invention. Figure 2 This is a schematic diagram of the sealed heating device of the present invention. Detailed Implementation

[0015] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0016] like Figure 1-2 As shown in some illustrative embodiments, a portable detection and analysis device for coagulated particulate matter from stationary pollution sources is provided, comprising: a sampling gun unit 100, a pretreatment unit 200, an analysis unit 300, and a sampling unit 400.

[0017] The sampling gun unit 100 is used to extract flue gas samples from the exhaust gas conveying pipe 500 and send them to the subsequent processing unit. Specifically, it includes: sampling nozzle 1, Pitot tube 2, flue gas temperature sensor 3, sampling tube 4, heating and insulation sleeve 5, and temperature controller 6.

[0018] Sampling nozzle 1 is located at the front end of sampling gun unit 100. Its function is to ensure that the velocity of the flue gas entering sampling gun unit 100 is consistent with the actual flow velocity inside the exhaust gas conveying pipe 500, i.e., to achieve isokinetic sampling. Pitot tube 2 calculates the flue gas velocity in real time by measuring the difference between the total pressure and static pressure of the flue gas flow in exhaust gas conveying pipe 500. Flue gas temperature sensor 3 can be a platinum resistance thermometer or a thermocouple, used to measure the real-time temperature of the flue gas inside exhaust gas conveying pipe 500. Installation method: Sampling nozzle 1, Pitot tube 2, and flue gas temperature sensor 3 are integrated on a flange or fixing block, and extend together into the exhaust gas conveying pipe 500 through a standardized through-slot opened on the exhaust gas conveying pipe 500, ensuring that the measurement point and sampling point are consistent and the data is synchronized.

[0019] One end of the sampling tube 4 is connected to the sampling nozzle 1, and the other end of the sampling tube 4 is connected to the particulate cutter 7 in the pretreatment unit 200. A heating and insulation sleeve 5 is installed on the outer wall of the sampling tube 4. A temperature controller 6 is connected to the heating and insulation sleeve 5. The heating and insulation sleeve 5 can be a sleeve structure composed of an electric heating element and insulation material. The temperature controller 6 acquires the measurement data from the temperature sensor inside the heating and insulation sleeve 5 and controls the heating power of the electric heating element to stabilize the inner wall temperature of the sampling tube 4 at a set value.

[0020] The working process of the sampling gun unit 100 is as follows: the flue gas is first drawn at a constant speed through the sampling nozzle 1, and then enters the sampling tube 4 which is wrapped by the heated insulation sleeve 5. Under the control of the temperature controller 6, the sampling tube 4 is kept at a high temperature to ensure that the moisture and condensable substances in the flue gas are always in a gaseous state and no condensate is released. The flue gas that has been heated at high temperature is transported to the particulate cutter 7 in the pretreatment unit 200.

[0021] The pretreatment unit 200 receives high-temperature flue gas from the sampling gun unit 100 and performs processing steps such as removing interfering particulate matter, temperature-controlled condensation, and separating and temporarily storing the condensate to facilitate subsequent CPM collection and analysis. Specifically, it includes: a particulate matter cutter 7, a condenser tube 8, a semiconductor cooler 9, a condensate storage device 10, a metering peristaltic pump 12, a condensate drain pipe 13, and a condensate dripping pipe 14.

[0022] The particulate cutter 7, condenser 8, and condensate storage device 10 are connected in sequence. Flue gas from the sampling gun unit 100 first enters the particulate cutter 7. The particulate cutter 7 can be a cyclone or impact cutter, which, based on aerodynamic principles, cuts particles larger than PM2.5 in the flue gas. 2.5The particulate matter is separated and removed to ensure the accuracy of the measurement results. The cut flue gas then enters the condenser tube 8. The semiconductor cooler 9 is located on the outer wall of the condenser tube 8. After being energized, it generates a cooling effect, which can quickly and accurately control the temperature of the flue gas in the condenser tube 8 to about 30°C, meeting the standard requirements of EPA Method 202. The condenser tube 8 needs to be of sufficient length and can adopt a spiral or coil structure. This not only extends the contact time between the high-temperature flue gas and the low-temperature tube wall, ensuring sufficient heat exchange and condensation effect, but also achieves efficient cooling in a compact space, significantly reducing the size and weight of the entire cooling module, and facilitating the portability of the equipment.

[0023] The condensate formed in the condenser tube 8 and the cooled flue gas enter the condensate storage device 10 together. Due to gravity, the denser condensate settles to the bottom of the device, while the flue gas flows out from the upper part of the device. The upper part of the condensate storage device 10 is connected to the sealed heating device 15 of the pretreatment unit 200 through the flue gas passage 101, and the lower part of the condensate storage device 10 is connected to the sealed heating device 15 through the condensate dripping pipe 14. A metering peristaltic pump 12 is installed on the condensate dripping pipe 14.

[0024] The condensate drain pipe 13 is connected to the condensate dripping pipe 14, and the bottom of the condensate storage device 10 is provided with a condensate drain port 11 to facilitate thorough drainage and cleaning after sampling.

[0025] The condensate formed after cooling by the condenser tube 8 is temporarily stored in the condensate storage device 10. The flue gas continues to pass through the flue gas path 101 and is captured by the sampling membrane 18 in the analysis unit 300. After a certain period of sampling, sampling is stopped, and the sampling unit 400 records the sampling volume and duration, while simultaneously acquiring the condensate volume of the condensate storage device 10 entered by the sampling personnel. Then, the quantitative peristaltic pump 12 is started to extract the condensate, which is dripped into the sampling membrane 18 through the condensate dripping pipe 14.

[0026] The analysis unit 300 integrates the capture and weight analysis of CPM and specifically includes: a sampling membrane 18, a sealed heating device 15, a beta-ray source 16, and a radiation detector 17.

[0027] A sealed heating device 15 is used to support the sampling membrane 18, and its interior has a sampling position for the sampling membrane 18. The sealed heating device 15 includes a support base 151 and a sealed cover 152. The support base 151 has a groove for placing the sampling membrane 18, and a heating element, such as a cylindrical heater or a small PTC heating element, is installed inside the support base 151 to achieve localized heating, that is, the heat is mainly concentrated in the area in contact with the sampling membrane 18. At the same time, a thermocouple or thermistor is embedded near the heating area for monitoring and controlling the heating temperature. The sealed cover 152 is connected to the support base 151 by a hinge or thread. When the sealed cover 152 is closed on the support base 151, the sampling membrane 18 is pressed into the groove of the support base 151. An air extraction hole 153 is provided on the support base 151 for connecting the sampling unit 400. An air inlet hole 154 is provided on the sealed cover 152 for connecting the flue gas passage 101 and the condensate dripping pipe 14.

[0028] A beta-ray source 16 and a radiation detector 17 are spaced a certain distance apart to form an analysis position for placing a sampling diaphragm 18. The beta-ray source 16 and the radiation detector 17 are placed opposite each other to form a stable measurement field. The beta-ray source 16 continuously emits low-energy beta rays, while the radiation detector 17 receives the intensity of the rays after penetrating the sampling diaphragm 18.

[0029] The two-step capture workflow is as follows: Step 1: Capturing gaseous CPM: After passing through the pretreatment unit 200, the flue gas enters the closed heating device 15 through the flue gas path 101. At this time, the heating element in the closed heating device 15 is not activated, and the flue gas flows directly through the sampling membrane 18. During the cooling process, the condensable particulate matter in the flue gas undergoes homogeneous nucleation on the surface of the sampling membrane 18 and is captured, forming the first part of CPM.

[0030] Step 2: Capturing dissolved CPM: After the gaseous CPM is captured, the flue gas extraction is paused, and the metering peristaltic pump 12 is started to add condensate from the condensate storage device 10 onto the same sampling membrane 18. Then, the sealed heating device 15 and the sampling pump 21 in the sampling unit 400 are started in coordination. That is, the heating element in the sealed heating device 15 heats and evaporates the condensate on the sampling membrane 18, and the resulting water vapor is extracted by the sampling pump 21. As the water evaporates, the second part of CPM that was originally dissolved in the condensate precipitates out and is uniformly deposited on the sampling membrane 18.

[0031] After completing the above two collection steps, the sampling diaphragm 18 has collected all the CPM in the flue gas. Then, the sampling diaphragm 18 is moved from the collection position to the analysis position, i.e., between the beta-ray source 16 and the radiation detector 17. Beta rays penetrate the sampling diaphragm 18, and some rays are absorbed by the diaphragm 18 and the particles on it. The intensity of the rays received by the radiation detector 17 decreases. Based on the beta-ray attenuation law, the increased mass of particles on the sampling diaphragm 18 is calculated. Combining the sampling volume and sampling time recorded by the sampling unit 400 with the condensate volume entered by the operator, the device's control system calculates the final concentration of CPM in the flue gas, achieving rapid on-site detection.

[0032] The two-step collection method ensures that both gaseous CPM in the flue gas and CPM dissolved in the condensate are completely collected on the same membrane, avoiding sample loss, transfer errors, and computational complexity that may occur with traditional methods that separately process the filter membrane and absorbent, thus ensuring the accuracy of the measurement results. Furthermore, this structure allows for simultaneous sampling and analysis; the next sample can be collected and analyzed immediately after the first sample is collected. After sample collection, the condensate storage device 10 can be cleaned with ultrapure water, and the waste liquid is discharged by a peristaltic pump, after which the second sampling can be performed.

[0033] The sampling unit 400 includes a drying device 19, a metering device 20, and a sampling pump 21. The drying device 19 is connected to the sealed heating device 15, the metering device 20 is connected to the drying device 19, and the sampling pump 21 is connected to the metering device 20.

[0034] The flue gas is sampled and analyzed sequentially through sampling nozzle 1, sampling tube 4, particulate cutter 7, condenser 8, sampling diaphragm 18, drying device 19, metering device 20, and sampling pump 21. After passing through sampling diaphragm 18, the gas enters sampling unit 400. It first passes through drying device 19, which contains a desiccant, such as anhydrous magnesium perchlorate. Residual water vapor in the gas is absorbed by the desiccant, resulting in pure dry flue gas. Subsequently, the dry flue gas flows through metering device 20, which includes a flow meter and timer. The gas volume is measured and recorded in real time, and the sampling time is also recorded. Finally, the gas is extracted and vented by sampling pump 21.

[0035] Based on EPA Method 202, this invention enables portable detection and analysis of condensable particulate matter from stationary pollution sources through a sampling gun unit 100, a pretreatment unit 200, an analysis unit 300, and a sampling unit 400.

[0036] Before the test begins, the sampling membrane 18 is placed in the analysis position, and the background value of the filter is measured using beta rays. After the test is completed, the sampling membrane 18 is placed in the acquisition position, and then the test begins.

[0037] First, the sampling gun unit 100 is turned on. The flue gas passes through the sampling gun unit 100 and is heated at high temperature to ensure no condensation occurs in the sampling tube 4. The heated flue gas then enters the particulate matter cutter 7, which removes PM2.5 particles. 2.5 After the above particulate matter is removed, the flue gas then passes through the condenser 8 and the semiconductor cooler 9, which lowers the flue gas temperature to 30°C. At this time, condensate is formed and temporarily stored in the condensate storage device 10. The cooled flue gas enters the analysis unit 300, and the condensable particulate matter generated after cooling is intercepted by the sampling membrane 18.

[0038] After the sample collection is completed, the sampling pump 21 stops working. At this time, a certain amount of water has been stored in the condensate storage device 10. The quantitative peristaltic pump 12 adds a certain amount of condensate to the sampling membrane 18, and the heating element in the sealed heating device 15 and the sampling pump 21 are started. Through the coordinated work of heating and sampling pump 21, the condensate is evaporated. The water vapor is discharged by sampling pump 21, and the condensable particles formed after evaporation are intercepted by sampling membrane 18.

[0039] After completing the above steps, the sampling membrane 18 is adjusted from the collection position to the analysis position, and the concentration of condensable particulate matter on the sampling membrane 18 is measured by β-rays, thus realizing the rapid detection of condensable particulate matter.

[0040] The portable detection and analysis device for condensable particulate matter from stationary pollution sources provided by this invention has the following advantages compared to existing technologies: Integrating β-ray attenuation analysis technology into portable devices creates an integrated sampling and analysis unit, enabling rapid in-situ detection of condensable particulate matter and improving detection efficiency. By using a pre-cutting particle cutter to eliminate interference from large particles, the necessary conditions for homogeneous nucleation of condensable particles are created. The two-step collection measures quantitatively collect and enrich gaseous and dissolved condensable particles in the same medium, ensuring the integrity of sample collection and guaranteeing the accuracy and reliability of monitoring data. The technical principle of this invention follows the core process of the EPA Method 202 standard method. Based on this mature international standard, the measurement results of this device have high traceability and high reliability. Through modular design, traditionally dispersed equipment is highly integrated into one compact structure, making it easy to carry and significantly reducing operational complexity and human error. Compared with traditional manual monitoring methods, this invention improves on-site sampling speed and enhances on-site operational efficiency.

[0041] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A portable detection and analysis device for condensable particulate matter from stationary pollution sources, characterized in that, include: Preprocessing unit and analysis unit; The analysis unit includes: a sampling membrane and a sealed heating device for supporting the sampling membrane; The pretreatment unit includes: a particulate cutter, a condenser, a thermoelectric cooler, a condensate storage device, and a metering peristaltic pump. The thermoelectric cooler is disposed on the outer wall of the condenser. The particulate cutter, the condenser, and the condensate storage device are connected in sequence. The upper section of the condensate storage device is connected to the sealed heating device through a flue gas path. The lower section of the condensate storage device is connected to the sealed heating device through a condensate dripping pipeline. The metering peristaltic pump is disposed on the condensate dripping pipeline.

2. A portable detection and analysis device for condensable particulate matter from stationary pollution sources as described in claim 1, characterized in that, The analysis unit further includes a beta-ray source and a radiation detector, wherein the beta-ray source and the radiation detector are spaced apart by a certain distance to form an analysis position for placing the sampling membrane.

3. A portable detection and analysis device for condensable particulate matter from stationary pollution sources as described in claim 2, characterized in that, The pretreatment unit further includes: a condensate drain pipe, which is connected to the condensate dripping pipe; and a condensate drain port is provided at the bottom of the condensate storage device.

4. A portable detection and analysis device for condensable particulate matter from stationary pollution sources as described in claim 3, characterized in that, Also includes: Sampling unit; The sampling unit includes a drying device, a metering device, and a sampling pump. The drying device is connected to the sealed heating device, the metering device is connected to the drying device, and the sampling pump is connected to the metering device.

5. A portable detection and analysis device for condensable particulate matter from stationary pollution sources as described in claim 4, characterized in that, Also includes: Sampling gun unit; The sampling gun unit includes: a sampling nozzle, a pitot tube, a smoke temperature sensor, and a sampling tube; The sampling nozzle, the pitot tube, and the smoke temperature sensor are installed on the exhaust gas conveying pipeline. One end of the sampling tube is connected to the sampling nozzle, and the other end of the sampling tube is connected to the particulate cutter.

6. A portable detection and analysis device for condensable particulate matter from stationary pollution sources as described in claim 5, characterized in that, The sampling gun unit further includes a heating and insulation sleeve and a temperature controller; the heating and insulation sleeve is disposed on the outer wall of the sampling tube, and the temperature controller is connected to the heating and insulation sleeve.

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