Method and device for determining odor distribution range

Abstract

The present invention provides a method and device for determining the odor distribution range, belonging to the field of odor analysis technology, capable of accurately demarcating the odor distribution range. This method determines a first region within the plot of land to be analyzed by measuring the PID concentration of the odorous substance in the plot. The method then calculates the odor activity value based on the soil vapor concentration of the odorous substance. Based on the odor activity value, a second region within the first region is determined as the odor distribution range, thereby demarcating the odor distribution range and achieving more precise demarcation of the odor distribution region.

Description

Technical Field

[0001] The present invention relates to the technical field of odor analysis, and in particular to a method and device for determining the distribution range of odor. Background Art

[0002] In areas such as contaminated site remediation, industrial waste gas emissions, and sewage treatment, a variety of odorous chemicals are usually produced. These chemicals are volatile and will evaporate into the environment, causing harm to the survival and health of organisms and the ecological environment.

[0003] In the existing technology, the concentration of odorous pollutants is usually monitored at fixed points to assess the distribution range of odor, and odor risk control is performed on pollutants within the distribution range. However, this method has the problem of inaccurate delineation of the odor distribution range. Summary of the Invention

[0004] The present invention provides a method and device for determining the odor distribution range, which can more accurately define the odor distribution range.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention provides a method for determining an odor distribution range, comprising:

[0007] Determining a first region in the plot to be analyzed based on a PID concentration of at least one odorous substance at a plurality of points in the plot to be analyzed; the PID concentration is obtained by detection using a photoionization detector (PID); and, among the plurality of points, a concentration of the at least one odorous substance at a point belonging to the first region exceeds a standard;

[0008] obtaining soil gas concentrations of the at least one odorous substance at a plurality of measuring points in the first area;

[0009] calculating, based on the soil gas concentration of the at least one odorous substance at the plurality of measuring points, odor activity values ​​of the at least one odorous substance at the plurality of measuring points;

[0010] Based on the odor activity values ​​of the at least one odor substance at the multiple measuring points, the second area in the first area is determined to be the odor distribution area; the sum of the odor activity values ​​of the at least one odor substance in the second area is greater than 1.

[0011] The method for determining the odor distribution range provided by the present invention determines the first area in the plot to be analyzed by measuring the PID concentration of at least one odor substance at multiple points of the plot to be analyzed, and then calculates the odor activity values ​​of the multiple odor substances at the multiple measuring points based on the soil gas concentrations of the multiple odor substances at the multiple measuring points; based on the odor activity values, the second area in the first area is determined to be the odor distribution range, and the odor distribution range is delineated. The above method can more accurately reflect the diffusion and distribution state of the odor, and thus can accurately delineate the odor distribution range.

[0012] Further, obtaining the PID concentration of the at least one odorous substance at a plurality of measuring points of the plot to be analyzed;

[0013] Interpolation processing is performed on the PID concentrations of the at least one odor substance at multiple measuring points of the land to be analyzed to obtain the PID concentrations of the at least one odor substance at multiple points of the land to be analyzed.

[0014] Furthermore, in an implementation of the first aspect, determining the second area in the first area as the odor distribution area based on the odor activity values ​​of the at least one odor substance at the multiple measuring points includes:

[0015] Screening out at least one key off-flavor substance from the at least one off-flavor substance;

[0016] Based on the odor activity values ​​of the at least one key odor substance at the multiple measuring points, the second area in the first area is determined to be the odor distribution area; the sum of the odor activity values ​​of the at least one key odor substance in the second area is greater than 1.

[0017] Furthermore, in an implementation of the first aspect, screening at least one key odor substance from the at least one odor substance includes:

[0018] determining an odor activity value for each of the at least one odorous substance;

[0019] Determining the odor contribution rate of each odor substance according to the odor activity value of each odor substance;

[0020] According to the odor contribution rate of each odor substance, the at least one key odor substance is screened out from the at least one odor substance; wherein the sum of the odor contribution rates of the at least one key odor substance is greater than or equal to the odor contribution rate threshold, and the odor contribution rate of the at least one key odor substance is greater than or equal to the odor contribution rates of other odor substances in the at least one odor substance.

[0021] Furthermore, in an implementation of the first aspect, the multiple measuring points in the first area meet the following condition: the total soil concentration of at least one odorous substance at the measuring points is greater than the odor threshold of the at least one odorous substance.

[0022] Furthermore, in an implementation of the first aspect, when the PID concentration of the odor substance is greater than 1, the concentration of the odor substance exceeds the standard.

[0023] Furthermore, in an implementation of the first aspect, obtaining the soil gas concentration of each odorous substance at multiple measuring points in the first area includes:

[0024] detecting the concentration of each odor substance at a plurality of measuring points in the first area to obtain a total soil concentration of each odor substance at the plurality of measuring points;

[0025] Based on a three-phase equilibrium calculation model, the total soil concentration of each odorous substance at the multiple measuring points is converted into a soil gas concentration.

[0026] In a second aspect, the present invention provides a device for determining an odor distribution range, comprising a first determination module, an acquisition module, a calculation module, and a second determination module;

[0027] The first determination module is configured to determine a first region in the plot to be analyzed based on a PID concentration of at least one odorous substance at a plurality of points in the plot to be analyzed; the PID concentration is obtained by photoionization detection using a PID detector, and among the plurality of points, a concentration of the at least one odorous substance at a point belonging to the first region exceeds a standard;

[0028] The acquisition module is used to acquire the soil gas concentration of the at least one odorous substance at multiple measuring points in the first area;

[0029] The calculation module is used to calculate the odor activity value of the at least one odor substance at the multiple measuring points according to the soil gas concentration of the at least one odor substance at the multiple measuring points;

[0030] The second determination module is used to determine that a second area in the first area is an odor distribution area based on the odor activity value of the at least one odor substance at the multiple measuring points; and the sum of the odor activity values ​​of the at least one odor substance in the second area is greater than 1.

[0031] In an implementation of the second aspect, the first determination module is specifically configured to obtain a PID concentration of at least one odorous substance at a plurality of measurement points of a plot to be analyzed;

[0032] The PID concentrations of at least one odor substance at multiple measuring points of the plot to be analyzed are interpolated to obtain the PID concentrations of at least one odor substance at multiple points of the plot to be analyzed.

[0033] In an implementation of the second aspect, the second determining module is specifically configured to determine, based on the odor activity value of at least one odor substance at multiple measuring points, the second area in the first area as the odor distribution range, including:

[0034] Screening out at least one key off-flavor substance from at least one off-flavor substance;

[0035] Based on the odor activity value of at least one key odor substance at multiple measuring points, a second area in the first area is determined to be the odor distribution range; the sum of the odor activity value of at least one key odor substance in the second area is greater than 1.

[0036] Furthermore, in an implementation of the second aspect, the second determining module is specifically configured to screen at least one key odor substance from the at least one odor substance, including:

[0037] determining an off-flavor activity value for each of the at least one off-flavor substance;

[0038] According to the odor activity value of each odor substance, the odor contribution rate of each odor substance is determined;

[0039] At least one key odor substance is screened out from at least one odor substance based on the odor contribution rate of each odor substance; wherein the sum of the odor contribution rates of the at least one key odor substance is greater than or equal to the odor contribution rate threshold, and the odor contribution rate of the at least one key odor substance is greater than or equal to the odor contribution rates of other odor substances in the at least one odor substance.

[0040] Furthermore, in an implementation of the second aspect, the second determining module is specifically configured to determine the odor activity value of each of the at least one odor substance, including:

[0041] obtaining an odor threshold value of at least one odorous substance in the first area;

[0042] Based on an odor threshold of at least one odorous substance and a total soil concentration of at least one odorous substance at a plurality of measuring points in the first region, screening out at least one measuring point where the total soil concentration is greater than the odor threshold;

[0043] Calculate the odor activity value of each odor substance at at least one measuring point.

[0044] In an implementation of the second aspect, the first determination module is specifically configured to determine that when the PID concentration of the odor substance is greater than 1, the concentration of the odor substance exceeds the standard.

[0045] Furthermore, in an implementation of the first aspect, the acquisition module is specifically configured to detect the concentration of at least one odorous substance at a plurality of measuring points in the first area to obtain a total soil concentration of the at least one odorous substance at the plurality of measuring points;

[0046] Based on the three-phase equilibrium calculation model, the total soil concentration of at least one odorous substance at multiple measuring points is converted into soil gas concentration.

[0047] In a third aspect, the present invention provides an electronic device comprising a processor and a memory coupled to the processor; the memory is used to store computer instructions, and when the electronic device is running, the processor executes the computer instructions stored in the memory, so that the electronic device executes the method as described in the first aspect or any one of its implementations.

[0048] In a fourth aspect, the present invention provides a computer-readable storage medium comprising computer program instructions, which, when executed by a computer, enable the computer to execute the method according to the first aspect or any one of its implementations.

[0049] In a fifth aspect, the present invention provides a computer program product comprising computer program instructions, which, when executed on a computer, enable the computer to execute the method in the first aspect or any one of its implementations.

[0050] The technical effects corresponding to the above-mentioned second to fifth aspects and their possible implementation methods can refer to the above-mentioned description of the technical effects of the first aspect and its possible implementation methods, and will not be repeated here.

[0051] Beneficial effects of the present invention:

[0052] The method for determining the odor distribution range provided by the present invention determines the first area in the plot to be analyzed by measuring the PID concentration of at least one odor substance at multiple points of the plot to be analyzed, and then calculates the odor activity values ​​of the multiple odor substances at the multiple measuring points based on the soil gas concentrations of the multiple odor substances at the multiple measuring points; based on the odor activity values, the second area in the first area is determined to be the odor distribution range, and the odor distribution range is delineated. The above method can more accurately reflect the diffusion and distribution state of the odor, and thus can accurately delineate the odor distribution range. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 This is one of the schematic diagrams of the method for determining the odor distribution range provided in the embodiments of the present application;

[0054] Figure 2 This is the second schematic diagram of the method for determining the odor distribution range provided in the embodiment of the present application;

[0055] Figure 3 Schematic diagram of the range of the plot to be analyzed in the method for determining the odor distribution range provided in the embodiment of the present application;

[0056] Figure 4 It is a distribution diagram of multiple measuring points in the method for determining the odor distribution range provided in the embodiment of the present application;

[0057] Figure 5 This is one of the schematic diagrams of the odor distribution range simulated in the method for determining the odor distribution range provided in the embodiment of the present application;

[0058] Figure 6 This is the second schematic diagram of the odor distribution range simulated in the method for determining the odor distribution range provided in the embodiment of the present application;

[0059] Figure 7 It is a structural schematic diagram of the device for determining the odor distribution range provided in an embodiment of the present application. DETAILED DESCRIPTION

[0060] In the description and claims of the present invention, the terms "first" and "second" are used to distinguish different objects rather than to describe a specific order of objects.

[0061] In the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0062] In the description of the present invention, unless otherwise specified, "a plurality of" means two or more than two. For example, a plurality of measuring points means two or more than two measuring points.

[0063] The method and device provided in the embodiments of the present application relate to odor analysis, which can be used to determine the distribution range of odorous substances in a plot of land, that is, to determine in which area of ​​the plot the odorous substances are specifically distributed.

[0064] In plots of land where contaminated sites are remediated, industrial waste gas is discharged, and sewage is treated, odor pollutants that have long existed in the subsurface / waste gas / waste water may spread into the atmosphere of the plot, seriously damaging the quality of life of surrounding residents and reducing the reuse value of the plot.

[0065] For example, the types of plots to be analyzed and the causes of odor are as follows (1)-(3):

[0066] (1) The land for contaminated site remediation,

[0067] ① Soil excavation and treatment process: Contaminated soil releases volatile organic compounds (VOCs) such as benzene and toluene during excavation and treatment, producing a noticeable chemical odor. If organic matter in the soil decays, it may produce a foul odor similar to hydrogen sulfide (rotten eggs).

[0068] ② Groundwater extraction and treatment process: During the extraction and aeration process of contaminated groundwater, organic pollutants that can be dissolved in water may be released and produce odor.

[0069] ③Chemical application process: Chemical agents used in the soil and water treatment process, such as oxidants, reducing agents and neutralizers, may produce a specific chemical odor.

[0070] ④ Bioremediation process: Bioremediation technology that uses microorganisms to degrade pollutants, especially when treating organic pollutants, may produce organic degradation products with odor. Sometimes microbial activity produces volatile byproducts such as methane and other gases, which may cause odor.

[0071] ⑤ Thermal treatment and incineration process: When using thermal desorption and incineration technology to treat pollutants, the combustion products of pollutants may be released, generating smoke and odor.

[0072] ⑥ Volatile organic compound and steam extraction process: During the treatment process, pollutants evaporate from the soil or groundwater, especially during heat treatment or vapor phase extraction, which will produce a noticeable odor.

[0073] ⑦Organic pollutant treatment process: In the process of treating petroleum hydrocarbon pollutants (such as petroleum, diesel, and lubricating oil), especially when heated or aerated, volatile hydrocarbons will be released, producing a strong oily smell.

[0074] During the remediation of these sites, appropriate control measures are usually taken to reduce odors and prevent the spread of pollutants, such as the use of odor shielding agents, maintaining good ventilation, using closed systems and air purification equipment.

[0075] (2) Plots of land where industrial waste gas is emitted

[0076] Odors from industrial emissions can have various sources, depending on the type of industrial activity and the materials used.

[0077] ① Chemical industry: Volatile organic compounds (VOCs): such as benzene, toluene, and xylene, produce strong solvent odors. For example, ammonia produces a pungent odor; sulfides, such as hydrogen sulfide (H2S), produce a rotten egg smell.

[0078] ②Petroleum refining and petrochemical industry: Hydrocarbon compounds, such as alkanes, alkenes, and aromatics, produce obvious oil and fuel odors; sulfides, such as mercaptans, produce foul odors.

[0079] ③ Food processing: Fermentation of organic matter, such as in the winemaking and fermentation process, produces sour and yeasty taste; fat oxidation, such as in the processing of fried foods, produces greasy and sour smells.

[0080] ④ Paper and pulp industry: Sulfides, such as hydrogen sulfide and carbon disulfide, produce odors during pulp processing; chlorine and its derivatives may produce pungent odors during the bleaching process.

[0081] ⑤ Metal processing and electroplating: Acid mist, such as nitric acid, sulfuric acid, and hydrochloric acid, produces a pungent sour smell; solvent odor, such as solvents used for cleaning and degreasing, produces a chemical smell.

[0082] ⑥ Wastewater treatment: The decomposition of organic matter, such as methane, hydrogen sulfide and other foul-smelling gases, is produced during the wastewater treatment process; chlorine, when used for disinfection, produces a pungent odor.

[0083] ⑦ Plastic and rubber manufacturing: Monomers and solvents, such as styrene and methyl vinyl ketone, produce strong chemical odors; combustion by-products, such as the smell of burnt plastic during thermal processing.

[0084] ⑧Textile printing and dyeing: dyes and auxiliaries produce chemical odors during the dyeing and printing process; organic solvents, such as toluene and dichloromethane, produce strong solvent odors.

[0085] (3) Land for sewage treatment plants

[0086] Sewage treatment plants produce various odors during the sewage treatment process, which mainly come from the decomposition and treatment of organic matter and chemicals in the sewage.

[0087] ① Anaerobic decomposition: Hydrogen sulfide (H2S), which is produced by the decomposition of organic matter in sewage under anaerobic conditions and has a rotten egg smell; ammonia (NH3), which comes from the decomposition of organic nitrogen compounds and produces a pungent ammonia smell; organic volatile fatty acids, such as acetic acid and butyric acid, produce a sour and smelly smell.

[0088] ② Sludge treatment: Anaerobic digestion. During the anaerobic digestion of sludge, gases such as hydrogen sulfide and methane will be produced, which will produce a foul odor; sludge stacking. Untreated or improperly treated sludge stacking will emit a noticeable odor.

[0089] ③ Primary and secondary sedimentation tanks: scum and sediment, organic matter deposited at the bottom of the tank will decompose and produce odor, especially during the cleaning process.

[0090] ④ Aeration tank: Organic matter is degraded. Organic matter will produce odor during the aeration process. Although aeration helps to reduce odor, the microbial activity in the aeration tank will still produce some gas.

[0091] ⑤ Filtration and disinfection: Chlorine and its by-products may produce a pungent odor when chlorine is used for disinfection; ozone disinfection, although ozone itself helps to reduce odor, high concentrations of ozone will also produce a special odor.

[0092] ⑥ Wastewater collection and transportation system: accumulated water and sediment in the pipes, and sewage pipes that have not been cleaned for a long time will create an anaerobic environment and cause odor.

[0093] Combined with the above description of the types of plots to be analyzed and the causes of odor, in the process of odor control in plots that may produce odorous substances, it is usually necessary to first determine the distribution of odor by monitoring the concentration of pollutants (i.e. odorous substances) at fixed points, and then evaluate and control the odor risk of the plot based on the concentration of pollutants. However, since the concentration value at the fixed point cannot accurately represent the concentration of pollutants in other areas of the plot, and the concentration of each pollutant is not directly related to the odor generated by the pollutant (i.e., some pollutants have a higher concentration but produce less odor, and some pollutants have a lower concentration but produce a larger odor), this method has the problem of inaccurate delineation of the odor distribution range.

[0094] In order to solve the above-mentioned problem of inaccurate demarcation of the odor distribution range, an embodiment of the present application provides a method and device for determining the odor distribution range. By using the PID concentration (PID, Photoionization Detector, photoionization detector, PID concentration is a concentration of volatile organic compounds (VOCs) obtained by PID detection) of the odor substance, the first area where the concentration of the odor substance exceeds the standard in the analyzed plot is determined, and then according to the odor activity value of the odor substance, the second area where the sum of the odor activity values ​​of the odor substances in the first area is greater than 1 is determined as the odor distribution area. This technical solution can preliminarily perceive the odor distribution range based on the PID concentration of the odor substance, and then further determine a more accurate odor distribution range in combination with the odor activity value.

[0095] Before describing the specific solutions of the present invention, the following professional terms that may be involved in the solutions of the present invention are explained:

[0096] 1. Soil gas concentration:

[0097] Soil gas concentration refers to the concentration of odorous substances in the gas mixture in the soil pore space. This concentration reflects the content of pollutants in the soil pore gas. Unlike the aforementioned PID concentration, the PID concentration can quickly reflect the concentration of odorous substances in the air; however, due to the continuous volatilization of odorous substances, using soil gas concentration to analyze odorous substances is more accurate. In other words, PID concentration has the advantage of being quickly obtained, while soil gas concentration has the advantage of being able to accurately reflect the diffusion potential of odorous substances (that is, compared with PID concentration, the odor activity value calculated using soil gas concentration can better reflect the degree of odor emission of odorous substances).

[0098] 2. Total soil concentration:

[0099] The total soil concentration refers to the total content of odorous substances in the solid part of the soil, including odorous substances adsorbed on soil particles and odorous substances in soil pores. In other words, the total soil concentration includes the aforementioned volatile soil gas concentration (i.e. odorous substances in soil pore gas) and odorous substances on soil particles that are not easily volatile. Therefore, the total soil concentration can fully reflect the total amount of odorous substances, and the total soil concentration can be compared with the odor threshold to determine whether the odorous substance content of the plot exceeds the standard.

[0100] 3. Key odor substances:

[0101] Key odor substances refer to one or several chemical substances with a strong odor in the environment. These chemicals can cause olfactory discomfort to people and usually have a low odor threshold (that is, they can be detected by the olfactory system of humans or other organisms even at lower concentrations); key odor substances may have a negative impact on the environment and affect people's drinking experience and quality of life.

[0102] 4. Odor threshold:

[0103] The odor threshold refers to the threshold of the total concentration of odorous substances in the soil, which is calculated through the odor exposure model. Specifically, when the total concentration of odorous substances in the soil is greater than or equal to the odor threshold, it means that the odor pollution of the odorous substance is serious, and further calculation and analysis of the odor activity value is required. When the total concentration of odorous substances in the soil is less than the odor threshold, it means that the odor pollution of the odorous substance is within the acceptable range of the human body or other organisms, and there is no need to perform the next step of odor activity value analysis and calculation.

[0104] 5. Odor activity value:

[0105] Odor Activity Value (OAV) refers to the contribution of a chemical substance (odorant) to odor in the biological (human) senses. It is used to quantify the extent to which a certain odorant contributes to the odor in the overall environment. The Odor Activity Value is obtained by the ratio of the soil gas concentration of a chemical substance to its olfactory threshold. Specifically, when the OAV of one or more odorants is greater than 1, it means that the concentration of the odorant exceeds its olfactory threshold and contributes to the overall odor, so measures need to be taken. The higher the OAV, the greater the contribution of the compound to the odor. Conversely, when the OAV is less than or equal to 1, the concentration of one or more odorants is lower than or equal to its olfactory threshold and may not have a significant impact on the odor of the sample, so no countermeasures are needed.

[0106] For example, the method for determining the odor distribution range provided in the embodiments of the present invention can be performed by an electronic device with processing capabilities, such as a computer or server. For example, if the electronic device is a computer, the hardware components of the computer may include: a processor, memory, a network interface, a user interface, a communication bus, etc.

[0107] The processor is used to control the electronic device to perform related processing and computing tasks, for example, the processor determines the first area and the odor distribution area. The processor may include a central processing unit (CPU) or other processor. The processor may be single-core or multi-core, for example, the processor may include multiple CPUs.

[0108] The memory is used to store computer instructions and related data. For example, the memory stores the PID concentration of odorous substances. The memory can be random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical storage, magnetic disk storage media or other magnetic storage devices, or any other medium capable of storing program code or data accessible by a computer. Optionally, the memory can be integrated into the processor or independent of the processor.

[0109] The network interface is used for the computer to communicate with other devices or communication networks. The network interface can be a transceiver with transceiver functions. Optionally, the network interface can include a standard wired interface or a wireless interface (such as a Wi-Fi interface, a Bluetooth interface, or a 5G interface).

[0110] The communication bus is used to achieve connection and communication between different components. For example, the processor, memory, network interface, and user interface mentioned above can be interconnected through the communication bus.

[0111] The user interface may include a display screen and an input unit (such as a keyboard). Optionally, the user interface may also include a standard wired interface and a wireless interface.

[0112] Those skilled in the art will appreciate that the above-mentioned computer may also include more or fewer components, or a combination of certain components, or different arrangements of components, which is not limited in the embodiments of the present application.

[0113] Based on the above content, Figure 1 As shown, the method for determining the odor distribution range provided in the embodiment of the present application includes S101-S104.

[0114] S101. Determine a first area in the plot to be analyzed based on the PID concentration of at least one odorous substance at multiple points in the plot to be analyzed.

[0115] In this embodiment of the present invention, among the multiple points in the plot to be analyzed, the concentration of the odorous substance at the points belonging to the first region exceeds the standard. Specifically, if the PID concentration of the odorous substance is greater than 1 ppm, the odorous substance concentration exceeds the standard. In other words, the region containing the points where the PID concentration of at least one odorous substance exceeds the standard among the multiple points in the plot to be analyzed is determined as the first region.

[0116] It can be understood that the PID concentration is obtained by detecting with a photoionization detector (PID).

[0117] Optionally, before obtaining the PID concentration of the odorous substance, the plot to be analyzed is first determined. For example, the plot to be analyzed can be determined through human perception or an expanded repair area (i.e., a certain width extending from the repair area). For example, human perception can be achieved through on-site inspections, using olfactory judgment, and recording multiple locations until the odor disappears. These locations are recorded as the scope of the plot to be analyzed.

[0118] For example, Figure 3 As shown, the range of the plot to be analyzed is Figure 3 The yellow frame part in .

[0119] Based on the plot to be analyzed obtained above, the first point distribution is performed on the plot to be analyzed according to the set grid (for example, Figure 4 As shown in the figure, the grid size is 40m*40m), and a measuring point is taken in each grid to obtain multiple measuring points. Then, the PID method is used to sample the soil surface (0-0.2m) / air at multiple measuring points of the analysis plot to obtain the PID concentration of volatile pollutants.

[0120] It should be understood that a PID (photoionization detector) is an instrument used to monitor the concentration of volatile organic compounds (VOCs); the working principle of a PID is to use an ultraviolet light source to ionize organic molecules into positive and negative ions that can be detected by the detector; the PID captures the positive and negative charges of the ionized gas and converts them into current signals, thereby achieving the measurement of gas concentration.

[0121] During the actual sampling process, due to equipment cost limitations, it is impossible to measure the PID concentration value at every location (point) on the plot to be analyzed. Therefore, a grid-based monitoring system is first used to detect the PID concentrations of multiple measuring points, thereby determining the approximate distribution range of volatile organic compounds (i.e., the first area mentioned above).

[0122] Combined with the PID concentrations of the above-mentioned multiple measuring points, the PID concentrations at the multiple measuring points of the plot to be analyzed are interpolated to obtain the PID concentrations of the odorous substances at the multiple points of the plot to be analyzed.

[0123] Optionally, the process of interpolating the PID concentrations of multiple measurement points includes the following S1-S4.

[0124] S1. Based on the known PID concentrations of multiple measuring points, calculate the distance between any two measuring points and the semi-variance between the two measuring points;

[0125] The distance between two measuring points can be Euclidean distance, for example, the measuring point (x i ,y i ) and measuring point (x j ,y j ) is: Measuring point (x i ,y i ) and measuring point (x j ,y j )'s semivariance r i,j for: Among them, there are n measurement points, i∈(1, 2, ..., n); j∈(1, 2, ..., n);

[0126] S2. Draw a scatter plot based on the known distances and semivariances between the measuring points, perform fitting, and obtain a fitting curve r = r(d);

[0127] S3. For the unknown point (i.e. the unknown point in the plot to be analyzed) (x0, y0), calculate its distance to all known measurement points (x i ,y i ) and calculate the semivariance r through the above fitting curve i,0 ;

[0128] S4. Using semivariogram ri,j , solve the weight coefficient λ i ; Then use the weight coefficient λ i The PID concentration of the known points (i.e., the measurement points in the plot to be analyzed) is weighted summed to obtain the estimated PID concentration value z of the unknown measurement point. o , z o satisfy

[0129] Specifically, the measuring point (x i ,y i ) PID concentration value z i (x i ,y i ) satisfies, z i (x i ,y i )=c+R(x i ,y i ), where c = E[z(x,y)]; R(x i ,y i ) represents the point (x i ,y i ) deviation;

[0130] According to the semivariance r obtained above i,j , use the following formula to solve the weight coefficient λ i ;

[0131]

[0132] Where φ is the Lagrange multiplier.

[0133] In another implementation of the present invention, the inverse distance weighted method may also be used for interpolation processing. The specific interpolation process may refer to the description of the existing technical materials, and will not be described in detail in the embodiment of the present invention.

[0134] In summary, by interpolating the PID concentration, the PID concentration data in other areas of the plot to be analyzed except for the measurement point can be filled in, making the data more complete, improving the data resolution, reducing the measurement cost, and at the same time, improving the accuracy of the first area.

[0135] S102: Obtain soil gas concentration of at least one odorous substance at multiple measuring points in the first area.

[0136] Optional, combined Figure 1 ,like Figure 2 As shown, S102 may include the following S1021-S1022.

[0137] S1021. Detect the concentration of at least one odorous substance at multiple measuring points in the first area to obtain the total soil concentration of multiple odorous substances at the multiple measuring points.

[0138] In an embodiment of the present invention, multiple measuring points in the first area meet the following conditions: the total soil concentration of at least one odorous substance at the measuring points is greater than the odor threshold of the at least one odorous substance (i.e., the total soil concentration of a certain odorous substance is greater than the odor threshold of the odorous substance).

[0139] Optionally, the method for obtaining multiple measuring points in the first area is as follows: points are arranged in the first area according to an 80m*80m grid to obtain several measuring points in the first area, surface soil samples of the several measuring points are collected and sent for inspection and analysis, and the total soil concentration C of each odor substance at each measuring point is obtained. s After obtaining several measuring points in the first area, multiple measuring points are screened out based on the total soil concentration of these measuring points to obtain multiple measuring points where the total soil concentration of odorous substances is greater than the odor threshold, specifically including A1-A2.

[0140] A1. Obtaining an odor threshold value of at least one odorous substance in a first area;

[0141] In the embodiment of the present invention, odorous substances in the soil volatilize into the atmosphere in the form of soil vapor, mix with air, and are perceived by the human sense of smell. The volatilization flux in this process includes two stages: the first stage, in which the odorous substances in the soil vapor diffuse into the atmosphere mainly in the form of molecular diffusion in the boundary retention layer near the surface; the second stage, in which the odorous substances diffuse into the atmospheric mixing zone, mix with air, and migrate with the wind.

[0142] The volatilization flux of the first stage (the stage in which soil gas diffuses into the atmosphere mainly in the form of molecular diffusion in the boundary stagnant layer near the surface) satisfies formula (6):

[0143]

[0144] Where Flux is the volatilization flux of odorous substances in the boundary stagnant layer near the surface and diffuses into the atmosphere, mg / (m 2 .s); Da is the diffusion coefficient of odorous substances in the air (m 2 .s); Csg is soil gas concentration, mg / m 3 ; d is the thickness of the boundary retention layer, which is 1 cm, and Ca is the VOCs concentration in the atmospheric mixing zone.

[0145] The volatilization flux of the second stage (the stage in which the odorous substance diffuses into the atmospheric mixing zone, mixes with the air and migrates with the wind) satisfies formula (7):

[0146]

[0147] Where Ws is the width of the soil excavation area, which is 50 cm; As is the area of ​​the soil excavation area, which is 2500 cm 2 , δair is the height of the mixing zone, Uair is the atmospheric flow velocity in the mixing zone.

[0148] According to the flux continuity principle, the volatilization fluxes in the first stage and the second stage are equal. By combining equations (6) and (7) and combining them with the three-phase equilibrium model (the three-phase equilibrium model is shown in S1022 below), the relationship between the odor threshold of the odor substance and the odor threshold of the odor substance can be derived, as shown in the following equation (8): The meaning, value and source of the parameters in equation (8) can be seen in Table 1;

[0149]

[0150] Where OT is the olfactory threshold, W s is the width of soil excavation area, A s is the area of ​​soil excavation area, U air Atmospheric air velocity in the mixing zone, δ air Height of mixing zone, D a is the diffusion coefficient of pollutants in the air; d is the thickness of the boundary retention layer; f oc is the soil organic carbon content, K oc is the partition coefficient of organic compounds between organic carbon and water, ρ b is the soil bulk density, θ air is the volume ratio of soil pore air, H is Henry coefficient, θ water is the volume ratio of pore water in the soil layer.

[0151] Table 1 Parameter values ​​of odor exposure model

[0152] name meaning Value Value Source <![CDATA[f oc ]]> Soil organic carbon content 0.023 Measured value of the plot <![CDATA[ρ b ]]> Soil bulk density, kg / dm3 1.39 Measured value of the plot <![CDATA[θ air ]]> Soil pore air volume ratio 0.00247 Measured value of plot <![CDATA[θ water ]]> Soil pore water volume ratio 0.4865 Measured value of plot <![CDATA[U air ]]> Air velocity in the mixing zone, m / s 2 Recommended parameters for HJ.3-2019 <![CDATA[δ air ]]> Height of mixing zone, m 2 Recommended parameters for HJ.3-2019

[0153] A2. Based on the odor threshold of at least one odorous substance and the total soil concentration of at least one odorous substance at multiple measuring points in the first area, select at least one measuring point from the multiple measuring points where the total soil concentration is greater than the odor threshold.

[0154] Exemplarily, among n measuring points {a1, a2, ..., an}, m measuring points are selected where the total concentration of odorous substances in the soil is greater than the odor threshold.

[0155] S1022. Based on a three-phase equilibrium calculation model, the total soil concentrations of various odorous substances at multiple measuring points are converted into soil gas concentrations.

[0156] Specifically, using the above-mentioned total soil concentration and three-phase equilibrium calculation model, the total soil concentration of each odor substance C s Converted to soil gas concentration Csg .

[0157] It should be understood that the three-phase equilibrium calculation model is a model that converts the concentration of a substance in one state to the concentration in another state, including a water phase-gas phase conversion model, a water phase-solid phase conversion model, and a gas phase-solid phase conversion model.

[0158] The gas phase conversion model can convert the concentration of odorous substances in soil gas with the concentration of odorous substances in soil water film. The water phase to gas phase conversion model is:

[0159] C sg =H×C w (1)

[0160] In formula (1), C sg is the concentration of odorous substances in soil gas, in mg / m 3 ; C w is the concentration of VOCs in the soil water film, in mg / L; H is the Henry coefficient, dimensionless.

[0161] The water-solid phase conversion model can convert the content of odorous substances in the soil water film into the content of odorous substances in the soil solid phase. The water-solid phase conversion model is:

[0162] C p =K d ×C w (2)

[0163] In formula (2), C w is the VOCs concentration in the soil water film, in mg / L; C p is the concentration of odorous substances in soil solid particles, in mg / kg; K d is the soil-water partition coefficient.

[0164] The gas-solid phase conversion model can convert the concentration of odorous substances in soil gas into the content of odorous substances in the soil solid phase. The gas-solid phase conversion model is:

[0165] C p =K p ×C sg (3)

[0166] In formula (3), C sg is the soil gas concentration of odorous substances, in mg / m 3 ; C p is the concentration of odorous substances in soil solid particles, in mg / kg; Kp is the soil-air partition coefficient, dimensionless.

[0167] According to mass balance, the total mass of VOCs in the solid phase, water phase and gas phase in the soil should satisfy formula (4)

[0168] C s ×ρ=C w ×θ w +C sg ×θ a +C p ×ρ (4)

[0169] Where C s is the total soil concentration, i.e., the concentration obtained by collecting surface soil samples and sending them for analysis, mg / kg; ρ is the soil bulk density, kg / m 3 ; C sg is the soil gas concentration, mg / m 3 θ W is the water content in the contaminated soil, dimensionless; θ a is the air content in the contaminated soil, dimensionless; C p It is the concentration of odorous substances in soil solid particles, mg / kg.

[0170] Summarizing the above formulas (1) to (4), it can be seen that the total soil concentration and soil gas concentration satisfy the following formula (5):

[0171]

[0172] Where θ W is the water content in the contaminated soil, dimensionless; θ a is the air content in the contaminated soil, dimensionless; K d is the soil-water partition coefficient, m 3 / kg; where K d =K oc ×f oc ;K oc is the partition coefficient of organic compounds between organic carbon and water, m 3 / kg;f oc is the percentage of soil organic carbon, dimensionless.

[0173] By converting the concentration of each odor substance at each measuring point through the above S1021-S1022, the soil gas concentration of at least one odor substance at multiple measuring points can be obtained. The soil gas concentrations of these odor substances can be used to calculate the odor activity value and then divide the area, as shown in the following S103-S104.

[0174] S103. Calculate the odor activity value of the at least one odor substance at the multiple measuring points based on the soil gas concentration of the at least one odor substance at the multiple measuring points.

[0175] Among them, each odor substance at each measuring point has its foreign matter activity value.

[0176] The odor activity value meets the following requirements:

[0177] OAV i =C i / OT i (9)

[0178] Where OAVi is the odor activity value of odor substance i; Ci is the soil gas concentration of odor substance i (i.e., C sg ), mg / m 3 ;OT i is the odor threshold of odor substance i in mg / m 3 .

[0179] S104. Determine, based on the odor activity value of at least one odor substance at multiple measuring points, that a second area in the first area is an odor distribution area; and the sum of the odor activity values ​​of the at least one odor substance in the second area is greater than 1.

[0180] Optional, combined Figure 1 ,like Figure 2 As shown, the above S104 includes S1041-S1042.

[0181] S1041. Screening out at least one key odor substance from at least one odor substance;

[0182] It should be understood that since the measuring points can detect many types of chemical substances (odor substances), among these odor substances, the odor activity value of each odor substance is different (that is, some odor substances have a higher content but a smaller odor, and some have a small content but a larger odor). Therefore, it is necessary to screen these odor substances and obtain key odor substances (that is, substances with a larger odor); using these key odor substances to delineate the odor area can reduce the amount of calculation and improve the accuracy of area division.

[0183] The calculation method of key odor substances includes steps 1)-3):

[0184] 1) determining the odor activity value of each of the at least one odor substance;

[0185] Specifically, the calculation method of the odor activity value is as shown in the above formula (9),

[0186] 2) determining the odor contribution rate of each odor substance according to the odor activity value of each odor substance;

[0187] Specifically, first add the odor activity values ​​of each odor substance to obtain the total odor activity value, and then use the ratio of the odor activity value to the total odor activity value to determine the odor contribution rate as shown in the following formula:

[0188] The total odor activity value (Summed OAV of Odorous Substances, SOAV) satisfies formula (10):

[0189]

[0190] The odor contribution rate satisfies formula (11):

[0191] P i =OAV i ×100% / SOAV (11).

[0192] Where, P i is the odor contribution rate of odor substance i, unit is %, C sg is the soil gas concentration, in mg / m 3 ; C s It is the total soil concentration, that is, the concentration obtained by collecting surface soil samples and sending them for inspection and analysis, and the unit is mg / kg.

[0193] 3) Screening out the at least one key odor substance from the at least one odor substance according to the odor contribution rate of each odor substance.

[0194] Among them, the sum of the odor contribution rates of the at least one key odor substance is greater than or equal to the odor contribution rate threshold, and the odor contribution rate of the at least one key odor substance is greater than or equal to the odor contribution rates of other odor substances in the at least one odor substance.

[0195] For example, when the odor contribution rate threshold is set to 80%, it means that multiple odor substances are arranged according to the size of the odor contribution rate, and added from large to small. When the sum of the odor contribution rates of the multiple odor substances is 80%, these odor substances are selected and used as key odor substances.

[0196] It should be understood that for a certain odor substance, an odor activity value can be obtained at each measuring point. However, in the process of calculating and using the odor activity value of the odor substance to screen key odor substances, it is necessary to determine the odor substance with the largest odor contribution rate among all the odor substances in the first area. That is to say, for an odor substance, a unique odor activity value of the odor substance needs to be determined in the first area.

[0197] In one implementation, the average value of the odor activity values ​​at the m measuring points may be calculated, and the average value of the odor activity values ​​may be used as the unique odor activity value of the odor substance in the first area.

[0198] In another implementation, the m measurement points obtained by the above screening are used to calculate the odor activity value. For example, for a certain odor substance W, the average value of the total soil concentration of the odor substance W in the m measurement points (denoted as ) as the total soil concentration of the odorous substance W in the first region, and Substituted into the above formula (5), the soil gas concentration of the odorous substance W in the first area is calculated as Substituting into the above formula (9), the odor activity value of the odor substance W in the first area is calculated.

[0199] Optionally, S104 includes S1041 - S1042 .

[0200] S1042. Determine, based on the odor activity values ​​of the at least one key odor substance at multiple measuring points, that a second area in the first area is an odor distribution area; and the sum of the odor activity values ​​of the at least one key odor substance in the second area is greater than 1.

[0201] For example, Figure 5 As shown in Figure 2, the odor distribution range can be simulated by ArcGIS software. Specifically, the above odor activity value data are imported into ArcGIS, and the distribution of the data is checked through the "Exploratory Data Analysis" tool of ArcGIS. The spatial autocorrelation of the data is analyzed through the "Semivariogram / Covariance Function" tool, and an appropriate semivariogram model (such as spherical, exponential, Gaussian, etc.) is selected and fitted to the data. The model parameters, such as the range, are adjusted until the best fit is obtained. The results are converted into contour maps or heat maps to obtain the following: Figure 5 Visualization of the concentration distribution.

[0202] In another implementation of the present invention, the simulation results obtained by interpolation processing using the inverse distance weighted method are as follows: Figure 6 As shown in the figure, it was found through on-site sampling that the interpolation processing results of S1-S4 are more accurate.

[0203] In summary, the method for odor distribution orientation provided in the embodiment of the present application determines the first area where the concentration of odor substances exceeds the standard in the plot to be analyzed based on the PID concentration of at least one odor substance at multiple points of the plot to be analyzed, and then calculates the odor activity values ​​of the odor substances at multiple measuring points based on the soil gas concentration of the odor substances in the first area; and based on the odor activity values ​​of multiple odor substances, determines that the second area where the sum of the odor activity values ​​in the first area is greater than 1 is the odor distribution area, thereby delineating the odor distribution range in the plot to be analyzed. This method uses PID for primary screening and odor activity value for secondary screening, and can more accurately delineate the pollution range. Compared with the existing technology that only relies on gas concentration judgment, this scheme uses soil gas concentration and odor activity value to participate in the calculation, which can accurately reflect the diffusion and distribution state of the odor (that is, considering that soil gas diffusion and odor activity value can describe the odor degree of the plot), and thus can accurately delineate the odor distribution range.

[0204] Accordingly, the embodiment of the present application provides a device for determining the odor distribution range, such as Figure 7 As shown, it includes a first determining module 501 , an acquiring module 502 , a calculating module 503 and a second determining module 504 .

[0205] The first determination module 501 is used to determine the first area in the plot to be analyzed based on the PID concentration of at least one odor substance at multiple points in the plot to be analyzed; the PID concentration is obtained by PID detection using a photoionization detector, and among the multiple points, the concentration of the at least one odor substance at the points belonging to the first area exceeds the standard; for example, the first determination module 501 is used to implement S101 in the above-mentioned method for the odor distribution range, and specifically also includes S1011-S1014.

[0206] The acquisition module 502 is used to obtain the soil gas concentration of the at least one odorous substance at multiple measuring points in the first area; for example, the acquisition module 502 is used to implement S102 in the above-mentioned method of odor distribution range, specifically including S1021-S1022.

[0207] The calculation module 503 is used to calculate the odor activity value of the at least one odor substance at the multiple measuring points based on the soil gas concentration of the at least one odor substance at the multiple measuring points; for example, the calculation module 503 is used to implement S103 in the above-mentioned method of odor distribution range.

[0208] The second determination module 504 is configured to determine, based on the odor activity values ​​of the at least one odor substance at the multiple measuring points, that a second region within the first region is an odor distribution region; the sum of the odor activity values ​​of the at least one odor substance within the second region is greater than 1. For example, the second determination module 504 is configured to implement S104 in the above-described method for odor distribution range, specifically including S1041-S1042.

[0209] The various modules of the above-mentioned device for determining the odor distribution range can also be used to execute other steps in the above-mentioned method embodiment. All relevant contents involved in the above-mentioned method embodiment can be referred to the functional description of the corresponding functional module and will not be repeated here.

[0210] The present application also provides an electronic device comprising: a processor and a memory coupled to the processor; the memory is configured to store computer instructions, and when the electronic device is in operation, the processor executes the computer instructions stored in the memory, causing the electronic device to perform the method described in the above embodiment. The processor can implement the first determination module 501, acquisition module 502, calculation module 503, and second determination module 504; the memory can also be configured to store PID concentrations, etc.

[0211] An embodiment of the present application further provides a computer-readable storage medium, which includes a computer program. When the computer program runs on a computer, the method described in the above embodiment is executed.

[0212] An embodiment of the present application further provides a computer program product, which includes computer program instructions. When the computer program instructions are run on a computer, the method described in the above embodiment is executed.

[0213] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0214] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for determining the distribution range of odor, characterized in that: include: Determining a first area in the plot to be analyzed based on the PID concentration of at least one odorous substance at multiple points in the plot to be analyzed; The PID concentration is obtained by using a photoionization detector (PID) for detection, wherein the concentration of the at least one odorous substance at the point belonging to the first area among the plurality of points exceeds the standard; obtaining soil gas concentrations of the at least one odorous substance at a plurality of measuring points in the first area; calculating, based on the soil gas concentration of the at least one odorous substance at the plurality of measuring points, odor activity values ​​of the at least one odorous substance at the plurality of measuring points; Screening out at least one key off-flavor substance from the at least one off-flavor substance; Based on the odor activity values ​​of the at least one key odor substance at the multiple measuring points, the second area in the first area is determined to be the odor distribution area; the sum of the odor activity values ​​of the at least one key odor substance in the second area is greater than 1.

2. The method according to claim 1, wherein The method further comprises: Obtaining the PID concentration of the at least one odorous substance at a plurality of measuring points of the plot to be analyzed; Interpolation processing is performed on the PID concentrations of the at least one odor substance at multiple measuring points of the land to be analyzed to obtain the PID concentrations of the at least one odor substance at multiple points of the land to be analyzed.

3. The method according to claim 1, wherein The step of screening at least one key off-flavor substance from the at least one off-flavor substance comprises: determining an odor activity value for each of the at least one odorous substance; Determining the odor contribution rate of each odor substance according to the odor activity value of each odor substance; According to the odor contribution rate of each odor substance, the at least one key odor substance is screened out from the at least one odor substance; wherein the sum of the odor contribution rates of the at least one key odor substance is greater than or equal to the odor contribution rate threshold, and the odor contribution rate of the at least one key odor substance is greater than or equal to the odor contribution rates of other odor substances in the at least one odor substance.

4. The method according to claim 3, wherein The plurality of measuring points in the first area meet the following condition: the total soil concentration of at least one odorous substance at the measuring points is greater than the odor threshold of the at least one odorous substance.

5. The method according to claim 1, wherein When the PID concentration of the odorous substance is greater than 1 ppm, the concentration of the odorous substance exceeds the standard.

6. The method according to claim 1, wherein Obtaining the soil gas concentration of each odorous substance at multiple measuring points in the first area includes: detecting the concentration of each odor substance at a plurality of measuring points in the first area to obtain a total soil concentration of each odor substance at the plurality of measuring points; Based on a three-phase equilibrium calculation model, the total soil concentration of each odorous substance at the multiple measuring points is converted into a soil gas concentration.

7. A device for determining the distribution range of odor, characterized in that: It includes a first determining module, an acquiring module, a calculating module and a second determining module; The first determination module is configured to determine a first region in the plot to be analyzed based on a PID concentration of at least one odorous substance at a plurality of points in the plot to be analyzed; the PID concentration is obtained by photoionization detection using a PID detector, and among the plurality of points, a concentration of the at least one odorous substance at a point belonging to the first region exceeds a standard; The acquisition module is used to acquire the soil gas concentration of the at least one odorous substance at multiple measuring points in the first area; The calculation module is used to calculate the odor activity value of the at least one odor substance at the multiple measuring points according to the soil gas concentration of the at least one odor substance at the multiple measuring points; The second determination module is used to screen out at least one key odor substance from the at least one odor substance; Based on the odor activity values ​​of the at least one key odor substance at the multiple measuring points, the second area in the first area is determined to be the odor distribution area; the sum of the odor activity values ​​of the at least one key odor substance in the second area is greater than 1.

8. An electronic device, characterized in that: The electronic device comprises a processor and a memory coupled to the processor; the memory is used to store computer instructions, and when the electronic device is running, the processor executes the computer instructions stored in the memory, so that the electronic device executes the method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that The method comprises computer program instructions, which, when executed by a computer, cause the computer to perform the method according to any one of claims 1 to 6.

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