Device and method for measuring independent PM2.5 emission rates of different cooking activities

Abstract

The invention relates to the technical field of indoor air pollution research, in particular to a device and method for measuring the independent PM2.5 emission rate of different cooking activities, the device comprises an operation table and a stove and a cooker supported by the operation table, the operation table is provided with a closed hood for closing the stove and the cooker, and the closed hood is provided with a hood door, a fan and a ventilation pipeline of the fan. The cover door is provided with an operation hole for experimenters to operate; the fan is positioned on one side of the top end of the enclosed hood to uniformly mix air in the enclosed hood; the ventilation pipeline is sequentially provided with a closed butterfly valve, a flowmeter, a fan and a ventilation opening at the top end of the closed cover; according to the invention, accurate measurement of the discharge amount of fine particulate matters in the cooking process can be effectively improved, and the defect of PM2.5 discharge monitoring of specific cooking activities in the prior art is overcome. According to the device and the method disclosed by the invention, the PM2.5 emission rate change in the cooking process can be monitored and recorded in real time, the instantaneous emission peak value and the overall emission trend are captured, and more detailed and accurate data support is provided for research and treatment.

Description

Technical Field

[0001] The present invention relates to the technical field of indoor air pollution research, and in particular to a method for independently performing PM2.5 and PM3.0 on different cooking activities. 2.5 Discharge rate measuring device and method. Background Art

[0002] Studies on human activity patterns show that people spend more than 80% of their time indoors. As society pays more attention to health and environmental quality, indoor air quality (IAQ) issues have gradually become the focus of public and scientific research. In recent years, with the deepening of understanding of indoor air pollution sources, components and their impact on human health, related research has also increased accordingly. There are many types of indoor air pollutants, including but not limited to fine particulate matter (PM 2.5 ), volatile organic compounds (VOCs), nitrogen oxides, and biological pollutants are the main sources of pollution in indoor activities, such as cooking activities and combustion processes. These pollutants have a significant impact on indoor air quality, which may pose a potential risk to the health of people living or working in this environment. Therefore, the assessment and improvement of indoor air quality, especially the study of unique indoor pollution sources, has become an important branch of environmental science, aiming to guide practice through scientific research to improve indoor environmental quality and protect human health. In the study of indoor air pollution (Household Air Pollution, HAP), it is crucial to understand and quantify the impact of different cooking activities on indoor air quality. Fumes, grease, and gas emissions during cooking are one of the main sources of indoor air pollution, especially in confined spaces. These emissions can significantly deteriorate indoor air quality and pose a potential threat to the health of residents. Therefore, measuring the emission rates of different cooking activities has become a key link in the study of indoor air pollution.

[0003] At present, the determination of indoor air pollutant emission rates mostly relies on direct measurement methods, that is, sampling and analysis in an open environment using various instruments and equipment. These methods usually include the use of particle concentration measuring instruments, gas analyzers, and other special equipment that can detect specific chemicals. This measurement method can provide real-time and direct pollutant concentration data, which is essential for evaluating the immediate impact of cooking activities on indoor air quality. However, this direct measurement method in an open environment also has limitations. For example, fluctuations in environmental conditions may affect the accuracy of the measurement results, and the infiltration of outdoor air may also interfere with the indoor air quality measurement.

[0004] 1) Lack of PM dedicated to cooking activities 2.5 Accurate emission measurement methods: In the existing technology, PM 2.5The measurement of emissions lacks specific consideration of cooking activities. This patent provides a method for measuring PM emissions from different cooking activities. 2.5 The device and method for measuring emission rates have enabled researchers to more accurately obtain PM2.5 emissions associated with cooking activities. 2.5 Emissions data.

[0005] 2) Insufficient research on fine particle pollution from cooking activities: Currently, there is little research on PM2.5 produced by cooking activities. 2.5 Emissions have been relatively poorly studied, and this patent could fill this gap by providing a specialized measurement method, facilitating in-depth research into fine particle pollution from cooking activities.

[0006] 3) Real-time monitoring and evaluation of cooking activity emission characteristics: Traditional methods may lack the ability to accurately understand the PM2.5 emissions from different cooking activities at different time periods. 2.5 Real-time monitoring capability of emission characteristics. The patented device and method can monitor and evaluate in real time, thereby more comprehensively reflecting changes in pollutant emissions during the cooking process.

[0007] The importance of this patent to the calculation of indoor activities’ emission factors of air pollutants is reflected in the following aspects:

[0008] 1) Provide data support for pollution factor model: The patented device and method can provide accurate PM 2.5 Emission data provides the necessary basic data for the establishment and optimization of pollution factor models, which helps to improve the accuracy of indoor air quality models.

[0009] 2) Improve the scientific nature of indoor air quality assessment: by accurately measuring PM during cooking activities 2.5 Emission rate, this patent can help to more accurately assess indoor air quality, thereby providing a basis for formulating more scientific air quality management strategies.

[0010] 3) Promote policy making and health risk assessment: Accurate PM 2.5 Emission rate data can help policymakers better understand the contribution of cooking activities to indoor air pollution and formulate more targeted pollution control policies. At the same time, the data is also of great reference value for assessing the health risks associated with cooking activities. Summary of the invention

[0011] The object of the present invention is to provide a method for independently performing different cooking activities. 2.5 The emission rate measuring device and method simulates indoor activities in a controlled environment and measures the emission rate of independent indoor activity sources, thereby improving the measurement accuracy. It can also reveal the specific contribution of different indoor activities to indoor air quality, and provide a scientific basis for indoor air pollution control and improvement.

[0012] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions:

[0013] A separate PM for different cooking activities 2.5 The emission rate measuring device includes an operating table and a stove and a cooker supported thereon, wherein the operating table is provided with a closed cover to seal the stove and the cooker, the closed cover is provided with a cover door, a fan and a ventilation duct, and the cover door is provided with an operation hole for the experimenter to operate; the fan is located at one side of the top of the closed cover to evenly mix the air in the closed cover; the ventilation duct is located at the top of the closed cover and is provided with a closed butterfly valve, a flow meter, a fan and a vent in sequence; multiple sets of PM 2.5 The online sensors are located at the top of the enclosure, next to the operating table outside the enclosure, and near the ventilation opening.

[0014] On the other hand, the present invention provides different cooking activities based on the above device independent PM 2.5 The method for determining the emission rate comprises the following steps:

[0015] S1: Before implementation, design the experimental plan and select the corresponding cooking activities, then organize the required equipment and ingredients, and perform equipment function tests to ensure the accuracy of data collection. In addition, according to the expected experimental conditions, prepare a standard operating procedure (SOP) to ensure the consistency and repeatability of the experimental process.

[0016] S2: Establish an experimental platform in a controlled environment, including placing an induction cooker and a wok on the operating table, and ensure that the temperature, humidity and other conditions of the test environment meet the predefined standards; at the same time, ensure that the quality and quantity of the raw materials used in the experiment meet the experimental requirements to avoid unnecessary fluctuations in experimental variables.

[0017] S3: The test space is sealed by closing the hood door, fan and butterfly valve to isolate external environmental interference and maintain the stability of the internal environment. Ensure that all particulate matter generated during the cooking process is confined in the closed space for subsequent concentration monitoring and analysis.

[0018] S4: PM inside and outside the closed hood and at the fan outlet 2.5 In-line sensors, calibrate the sensors to ensure data accuracy and reliability. Flow meters are tested to confirm the initial flow is zero in a closed environment so that changes in flow due to the increase of particulate matter during cooking activities can be accurately measured.

[0019] S5: Simulating cooking through the operating hole can ensure the isolation between the operator and the experimental environment, and ensure the safety and effectiveness of data collection. During this process, key parameters such as cooking time, temperature, and raw material input should be recorded.

[0020] S6: After the cooking process is completed, use a fan to evenly mix the air in the hood to ensure that the measured PM 2.5 The concentration data reflects an average level throughout the confined space. Controlling mixing time and fan speed is key to avoid biasing the particle concentration measurement.

[0021] S7: Open the fan and butterfly valve, control the exhaust rate of the gas in the hood through the fan, and monitor the gas flow in real time through the flow meter to maintain constant exhaust conditions. During the experiment, PM 2.5 Concentration, until the PM at the top of the closed hood, the operating table outside the closed hood and the near end of the ventilation port 2.5 Online sensor readings are stable and consistent. Accurately record data from all sensors, including PM 2.5 Concentration, flow rate and time, etc., provide accurate input for subsequent pollutant emission rate calculations.

[0022] S8: After the collection is completed, shut down the experimental devices one by one, including sensors, fans and other auxiliary equipment, and perform appropriate post-processing, such as data export, equipment cleaning and disinfection, to prepare for reuse.

[0023] Furthermore, the carbon mass balance method is used to calculate emission factors (EFs). In short, the total emissions from burning solid fuels in stoves are the sum of the total emissions emitted to the atmosphere through the flue or chimney. During the sampling process, the concentration of PM2.5 in the flue and leakage exhaust gas and the gas flow rate of the chimney exhaust are measured. According to the carbon balance principle, the equivalent volume flow rate of the leakage exhaust flue gas can be calculated;

[0024] It is assumed that the carbon released during fuel combustion mainly exists in the form of carbon monoxide, carbon dioxide, total hydrocarbons, and carbon in particulate matter (organic carbon and elemental carbon). Based on the conservation principle of carbon elements before and after fuel combustion, the following conclusions are drawn:

[0025]

[0026] C diff is the absolute difference of carbon in the ash before and after fuel combustion, C CO2 , C CO , C CH4 , and C PM Represents CO2, CO, CH4 and PM respectively 2.5 The mass of carbon in the CO2 Emission factor coefficient for carbon present;

[0027] M is the fuel mass E m-c C CO2 Emission factor for the carbon present; fCO2 is the conversion factor of carbon in carbon dioxide (41 / 12=3.67); using the above formula, the emission factor is calculated as:

[0028]

[0029] C x and C CO2 is the concentration mass of the compound and carbon dioxide.

[0030] On the other hand, the present invention proposes the above method to reduce PM from indoor active sources. 2.5 Application to emission rate studies.

[0031] Beneficial effects of the present invention:

[0032] The present invention provides a PM specifically for different cooking activities 2.5 The emission rate measuring device and method can effectively improve the accurate measurement of fine particulate matter emissions during cooking, filling the gap in the existing technology for PM2.5 emission in specific cooking activities. 2.5 The device and method of the invention can monitor and record PM in real time during cooking. 2.5 The emission rate changes can be captured to capture the instantaneous emission peak and overall emission trend, providing more detailed and accurate data support for research and governance. The present invention can be applied to a variety of cooking types and cooking environments (such as home kitchens, restaurants, food processing plants, etc.), and provides an operational technical solution for the study of emission characteristics of various cooking activities. 2.5 Based on the emission data of indoor air quality, the present invention can better evaluate the impact of these activities on indoor air quality and residents' health, and provide a scientific basis for formulating indoor air quality standards and improvement measures.

[0033] In indoor air quality research, the controllability of experimental conditions is crucial. The present invention can simulate the actual indoor cooking environment through a carefully designed closed experimental device, and can accurately control the variables in the experiment, such as temperature, humidity, air flow, etc. This level of control not only ensures high repeatability and accuracy of the research results, but also helps to analyze and understand the impact of specific cooking activities on indoor air quality in actual situations.

[0034] Utilize online PM 2.5 Sensors, this device enables real-time air quality monitoring, which is key to understanding the dynamics of indoor pollution. The sensors can accurately measure PM 2.5 The concentration changes provide real-time data for calculating the particle emission rate during the cooking process. In addition, by calibrating the sensor, the accuracy and reliability of the data can be ensured, providing a solid data foundation for subsequent analysis.

[0035] By independently PM different cooking activities 2.5 The accurate measurement of emission rates not only provides emission data for a single activity, but also allows for in-depth analysis, such as emission species analysis, source apportionment, etc. These data are critical for assessing the relative contribution of various cooking activities to indoor air quality and for assessing the health risks of these activities.

[0036] By using the method provided by the present invention, environmental health experts can quantitatively evaluate the PM generated by cooking activities. 2.5 Potential impact on occupant health. PM 2.5 Due to its tiny particle size and ability to penetrate deep into the respiratory tract, PM has been widely associated with respiratory and cardiovascular diseases. 2.5 Emission characteristics can provide guidance for reducing health risks associated with indoor pollution.

[0037] The invention provides new data and tools for developing indoor air quality management strategies, including but not limited to choosing healthier cooking methods and ingredients, improving kitchen ventilation systems, and educating residents on how to reduce pollution generated by cooking activities. Through the improved carbon balance calculation method, indoor environment managers can evaluate the effects of different interventions and optimize indoor air quality accordingly.

[0038] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0040] Figure 1 It is a schematic diagram of the overall structure of the device of the present invention;

[0041] Figure 2 It is a schematic diagram of the working structure of the device of the present invention;

[0042] In the figure: 1. Cooker, 2. Cooker, 3. Operation table, 4. Door, 5. Fan, 6. Sealed butterfly valve, 7. PM 2.5 Online sensor, 8. flow meter, 9. operation hole, 10. fan, 11. closed cover. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] Example 1

[0045] The different cooking activities described in this embodiment are independent PM 2.5 The emission rate measuring device comprises an operating table 3 and a stove 1 and a cooker 2 supported thereon, wherein the operating table 3 is provided with a closed cover 11 to seal the stove 1 and the cooker 2, the closed cover 11 is provided with a cover door 4, a fan 10 and a ventilation duct, and the cover door 4 is provided with an operation hole 9 for an experimenter to operate; the fan 10 is located at one side of the top of the closed cover 11 to evenly mix the air in the closed cover 11; the ventilation duct is located at the top of the closed cover 11 and is provided with a closed butterfly valve 6, a flow meter 8, a fan 5 and a vent in sequence; a plurality of PM 2.5 The online sensors 7 are respectively located at the top of the closed cover 11, beside the operating table 3 outside the closed cover 11 and near the ventilation port.

[0046] On the other hand, the present invention provides different cooking activities based on the above device independent PM 2.5 The method for determining the emission rate comprises the following steps:

[0047] S1: Before implementation, design the experimental plan and select the corresponding cooking activities, then organize the required equipment and ingredients, and perform equipment function tests to ensure the accuracy of data collection. In addition, according to the expected experimental conditions, prepare a standard operating procedure (SOP) to ensure the consistency and repeatability of the experimental process.

[0048] S2: Establish an experimental platform in a controlled environment, including placing an induction cooker and a wok on the operating table, and ensure that the temperature, humidity and other conditions of the test environment meet the predefined standards; at the same time, ensure that the quality and quantity of the raw materials used in the experiment meet the experimental requirements to avoid unnecessary fluctuations in experimental variables.

[0049] S3: The test space is sealed by closing the hood door, fan and butterfly valve to isolate external environmental interference and maintain the stability of the internal environment. Ensure that all particulate matter generated during the cooking process is confined in the closed space for subsequent concentration monitoring and analysis.

[0050] S4: PM inside and outside the closed hood and at the fan outlet 2.5In-line sensors, calibrate the sensors to ensure data accuracy and reliability. Flow meters are tested to confirm the initial flow is zero in a closed environment so that changes in flow due to the increase of particulate matter during cooking activities can be accurately measured.

[0051] S5: Simulating cooking through the operating hole can ensure the isolation between the operator and the experimental environment, and ensure the safety and effectiveness of data collection. During this process, key parameters such as cooking time, temperature, and raw material input should be recorded.

[0052] S6: After the cooking process is completed, use a fan to evenly mix the air in the hood to ensure that the measured PM 2.5 The concentration data reflects an average level throughout the confined space. Controlling mixing time and fan speed is key to avoid biasing the particle concentration measurement.

[0053] S7: Open the fan and butterfly valve, control the exhaust rate of the gas in the hood through the fan, and monitor the gas flow in real time through the flow meter to maintain constant exhaust conditions. During the experiment, PM 2.5 Concentration, until the PM at the top of the closed hood, the operating table outside the closed hood and the near end of the ventilation port 2.5 Online sensor readings are stable and consistent. Accurately record data from all sensors, including PM 2.5 Concentration, flow rate and time, etc., provide accurate input for subsequent pollutant emission rate calculations.

[0054] S8: After the collection is completed, shut down the experimental devices one by one, including sensors, fans and other auxiliary equipment, and perform appropriate post-processing, such as data export, equipment cleaning and disinfection, to prepare for reuse.

[0055] Example 2

[0056] In this example, the carbon mass balance method is used to calculate emission factors (EFs). In short, the total emissions from burning solid fuels in the stove are the sum of the total emissions released into the atmosphere through the flue or chimney. During the sampling process, PM in the flue and leak exhaust was measured. 2.5 The concentration of flue gas and the gas flow rate of chimney exhaust. According to the carbon balance principle, the equivalent volume flow rate of leaked flue gas can be calculated;

[0057] Assume that the carbon released during fuel combustion mainly exists in the form of carbon monoxide, carbon dioxide, total hydrocarbons (Total Hydrocarbon Carbon, THC, represented by CH4 in this embodiment) and carbon in particulate matter (organic carbon and elemental carbon). Based on the conservation principle of carbon element before and after fuel combustion, the following conclusions are drawn:

[0058]

[0059] C diff is the absolute difference of carbon in the ash before and after fuel combustion, C CO2 , C CO , C CH4 , and C PM Represents CO2, CO, CH4 and PM respectively 2.5 The mass of carbon in the CO2 Emission factor coefficient for carbon present;

[0060] M is the fuel mass E m-c C CO2 Emission factor for the carbon present; f CO2 is the conversion factor of carbon in carbon dioxide (41 / 12=3.67); using the above formula, the emission factor is calculated as:

[0061]

[0062] C x and C CO2 is the concentration mass of the compound and carbon dioxide.

[0063] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. An independent PM for different cooking activities 2.5 The device for measuring the emission rate is characterized in that The invention comprises an operating table (3) and a stove (1) and a cooker (2) supported thereon, wherein the operating table (3) is provided with a sealed cover (11) to seal the stove (1) and the cooker (2), the sealed cover (11) is provided with a cover door (4), a fan (10) and a ventilation duct, and the cover door (4) is provided with an operating hole (9) for an experimenter to operate; the fan (10) is located at one side of the top of the sealed cover (11) to evenly mix the air in the sealed cover (11); the ventilation duct is located at the top of the sealed cover (11) and is provided with a sealed butterfly valve (6), a flow meter (8), a fan (5) and a ventilation port in sequence; a plurality of PM groups are provided. 2.5 The online sensors (7) are respectively located at the top of the closed cover (11), beside the operating table (3) outside the closed cover (11) and near the ventilation opening.

2. Independent PM for different cooking activities based on the device of claim 1 2.5 A method for determining the emission rate, characterized in that: The following steps are involved: S1: Before implementation, design the experimental plan and select the corresponding cooking activities, then organize the required equipment and raw materials, and perform equipment function tests to ensure the accuracy of data collection; in addition, according to the expected experimental conditions, prepare standard operating procedures (SOPs) to ensure the consistency and repeatability of the experimental process; S2: Establish an experimental platform in a controlled environment, including placing an induction cooker and a wok on the operating table, and ensure that the temperature and humidity conditions of the test environment meet the predefined standards; at the same time, ensure that the quality and quantity of the raw materials used in the experiment meet the experimental requirements to avoid unnecessary fluctuations in experimental variables; S3: The test space is sealed by closing the hood door, fan and butterfly valve, thereby isolating the external environmental interference and maintaining the stability of the internal environment; ensuring that all particulate matter generated during the cooking process is confined in the closed space for subsequent concentration monitoring and analysis; S4: PM inside and outside the closed hood and at the fan outlet 2.5 In-line sensors, calibrate the sensors to ensure data accuracy and reliability; test flow meters to confirm the initial flow is zero in a closed environment so that changes in flow caused by the increase of particulate matter during cooking activities can be accurately measured; S5: Simulating cooking through the operating hole can ensure the isolation between the operator and the experimental environment, and ensure the safety and effectiveness of data collection; during this process, the key parameters of cooking time, temperature, and raw material input should be recorded; S6: After the cooking process is completed, use a fan to evenly mix the air in the hood to ensure that the measured PM 2.5 Concentration data reflects the average level of the entire confined space; controlling mixing time and fan speed is key to avoid biasing the measurement of particle concentration; S7: Open the fan and the butterfly valve, control the discharge rate of the gas in the hood through the fan, and monitor the gas flow in real time through the flow meter to maintain constant discharge conditions; During the experiment, PM should be continuously monitored. 2.5 Concentration, until the PM at the top of the closed hood, the operating table outside the closed hood and the near end of the ventilation port 2.5 Online sensor readings are stable and consistent; accurate recording of all sensor data, including PM 2.5 Concentration, flow rate and time, etc., provide accurate input for subsequent pollutant emission rate calculations; S8: After the collection is completed, shut down the experimental devices one by one, including sensors, fans and other auxiliary equipment, and perform appropriate post-processing, including data export, equipment cleaning and disinfection, to prepare for reuse.

3. The assay method according to claim 2, wherein: Emission factors were calculated using the carbon mass balance method; total emissions from burning solid fuels in stoves are the sum of total emissions released into the atmosphere through flues or chimneys; PM in flue and leak exhaust was measured during sampling. 2.5 The concentration and the gas flow rate of chimney exhaust; according to the carbon balance principle, calculate the equivalent volume flow rate of the leaked exhaust gas; Assuming that the carbon released during fuel combustion mainly exists in the form of carbon monoxide, carbon dioxide, total hydrocarbons and carbon in particulate matter; based on the conservation principle of carbon elements before and after fuel combustion, the following conclusions are drawn: C diff is the absolute difference of carbon in the ash before and after fuel combustion, C CO2 , C CO , C CH4 , and C PM Represents CO2, CO, CH4 and PM respectively 2.5 The mass of carbon in the CO2 Emission factor coefficient for carbon present; M is the fuel mass E m-c C CO2 Emission factor for the carbon present; f CO2 is the conversion factor of carbon in carbon dioxide; using the above formula, the emission factor is calculated as: C x and C CO2 is the concentration mass of the compound and carbon dioxide.

4. The method according to claim 2 or 3 for detecting PM2.5 in indoor active sources 2.5 Applications in emission rate studies.

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