Carbon emission measurement method and device for sewage treatment plants based on greenhouse gas detection

Abstract

The present invention provides a method and device for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection, the method comprising: obtaining gas data; determining measured direct carbon emission data based on the gas data; obtaining first production data required for direct carbon emission measurement and obtaining emission factors corresponding to the first production data; determining calculated direct carbon emission data based on the first production data and the corresponding emission factors; and determining the direct carbon emissions of the sewage treatment plant based on the measured direct carbon emission data and the calculated direct carbon emission data. The method according to an embodiment of the present invention determines the final direct carbon emissions of the sewage treatment plant by respectively obtaining the measured direct carbon emission data and the calculated direct carbon emission data, thereby improving the accuracy of the carbon emissions of the sewage treatment plant; in addition, the method provides a method for measuring carbon dioxide emissions from fossil sources in the biochemical reaction stage, thereby further improving the accuracy of carbon emission data of the sewage treatment plant.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and in particular to a method and device for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection. Background Art

[0002] Climate change is one of the major challenges facing the world today. Carbon emissions from the sewage treatment industry account for 1-2% of the total carbon emissions in society, ranking among the top ten carbon emission industries.

[0003] Regarding the carbon emission nucleic acid of sewage treatment plants, the calculation method based on emission factors proposed in the "IPCC 2006 National Greenhouse Gas Inventory Guidelines" is usually adopted. The core of this method is the selection of emission factors. First, the sources of emission factor data with higher quality are emission factors obtained by measurement / mass balance, empirical emission factors of the same process / equipment, and emission factors provided by equipment manufacturers. These emission factors are generally difficult to obtain; secondly, the sources of emission factors are regional emission factors, national emission factors, and international emission factors. These emission factors are currently the most commonly used data in carbon emission accounting, and there are problems such as large values ​​and lack of pertinence.

[0004] In addition, for key activities, carbon emissions are generally obtained through actual measurements. However, in fact, using only actual measurements to obtain carbon emissions is prone to large differences. Summary of the invention

[0005] In view of this, the present invention provides a method for measuring carbon emissions from sewage treatment plants based on greenhouse gas detection. The method determines the direct carbon emissions of sewage treatment plants through two measurement methods, thereby improving the accuracy of carbon emission measurement.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] On the one hand, a method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection according to an embodiment of the present invention includes:

[0008] Acquire gas data, where the gas data is data related to greenhouse gases generated in real time by the sewage treatment plant;

[0009] determining measured direct carbon emission data based on the gas data;

[0010] Obtain the first production data required for direct carbon emission measurement and obtain the emission factor corresponding to the first production data, wherein the first production data includes anaerobic bioreactor data, aerobic bioreactor data, denitrification added carbon source data, N 2 O data and CH 4 Any one or more of the data;

[0011] Determine and calculate direct carbon emission data based on the first production data and the corresponding emission factor;

[0012] Based on the measured direct carbon emission data and the calculated direct carbon emission data, the direct carbon emissions of the sewage treatment plant are determined.

[0013] Furthermore, based on the measured direct carbon emission data and the calculated direct carbon emission data, determining the direct carbon emission of the sewage treatment plant includes:

[0014] Determine whether the difference between the measured direct carbon emission data and the calculated direct carbon emission data is greater than a threshold,

[0015] When it is less than or equal to the threshold, the larger value between the measured direct carbon emission data and the calculated direct carbon emission data is used as the direct carbon emission amount;

[0016] When it is greater than the threshold, the uncertainties of the measured direct carbon emission data and the calculated direct carbon emission data are determined according to the uncertainty model respectively, and the one with the smaller uncertainty is used as the direct carbon emission amount.

[0017] Furthermore, the uncertainty model includes a first uncertainty model and a second uncertainty model, the first uncertainty model is used to determine the uncertainty of the measured direct carbon emission data, and the second uncertainty model is used to determine the uncertainty of the calculated direct carbon emission data, wherein the first uncertainty model is constructed based on the uncertainty of the gas data source, and the second uncertainty model is constructed based on the first production data source.

[0018] Further, the gas data comes from multiple detection points, wherein determining the measured direct carbon emission data based on the gas data includes:

[0019] T x =[∑ n i＝0 (T xi ) / n]*(S1 / S0);

[0020] Wherein, T is the measured direct carbon emission data, x is the gas data, i is the number of the ith detection point, n is the total number of detection points, S0 is the effective area of ​​a gas collection device of the detection device, and S1 is the total area of ​​the detection area.

[0021] Furthermore, it also includes:

[0022] Acquire second production data required for indirect carbon emission measurement, where the second production data includes one or more of power data and wastewater discharge data;

[0023] Obtaining an emission factor corresponding to the second production data;

[0024] According to the second production data and its corresponding emission factor, indirect carbon emissions are obtained.

[0025] Furthermore, it also includes:

[0026] Acquire third production data required for extended carbon emission measurement, wherein the third production data includes one or more of pharmaceutical production data and vehicle transportation data;

[0027] Obtaining an emission factor corresponding to the third production data;

[0028] The extended carbon emissions are obtained according to the third production data and its corresponding emission factor.

[0029] Furthermore, after determining the direct carbon emissions of the sewage treatment plant, it also includes:

[0030] The measured direct carbon emission data is used to calibrate the emission factors in the emission factor data, and a localized calibration emission factor database is formed.

[0031] Furthermore, using the measured direct carbon emission data to calibrate the emission factors in the emission factor data and forming a localized calibration emission factor database includes:

[0032] Based on different conditions, multiple values ​​are stored corresponding to the same emission factor in the localized verification emission factor database; wherein the different conditions include any one or more of the sewage treatment process, the sewage treatment scale, and the current temperature during sewage treatment.

[0033] On the other hand, an embodiment of the present invention further provides a carbon emission metering device for a sewage treatment plant based on greenhouse gas detection, comprising:

[0034] Online gas detection system, used to detect greenhouse gases generated by sewage treatment plants in real time and obtain gas data;

[0035] The production data collection system is used to collect the first production data required for direct carbon emission measurement of the sewage treatment plant in real time, wherein the first production data includes anaerobic biological reaction tank data, aerobic biological reaction tank data, denitrification added carbon source data, N 2 O data and CH 4 Any one or more of the data;

[0036] An industrial computer is used to obtain the gas data and the first production data, and obtain an emission factor corresponding to the first production data, and to determine and output the direct carbon emissions of the sewage treatment plant.

[0037] Furthermore, the online gas detection system comprises:

[0038] Gas collection components, used to collect greenhouse gases generated in real time by sewage treatment plants;

[0039] A gas detection component for detecting the concentration of collected greenhouse gases;

[0040] The gas collection tube is connected between the gas collection component and the gas detection component.

[0041] The above technical solution of the present invention has at least one of the following beneficial effects:

[0042] The present invention discloses a method and device for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection. The method determines the final direct carbon emissions of the sewage treatment plant by respectively obtaining measured direct carbon emission data and calculated direct carbon emission data, thereby improving the accuracy of the carbon emissions of the sewage treatment plant. In addition, the method provides a method for measuring carbon dioxide emissions from fossil sources in the biochemical reaction stage, thereby further improving the accuracy of carbon emission data from the sewage treatment plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 An overall flow chart of a method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection provided by an embodiment of the present invention;

[0044] Figure 2 A logical schematic diagram of using an uncertainty model to obtain a relatively accurate direct carbon emission amount in a method for measuring carbon emission of a sewage treatment plant based on greenhouse gas detection provided in an embodiment of the present invention;

[0045] Figure 3 A schematic diagram of a process for constructing a first uncertainty model and a second uncertainty model in a method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection provided by an embodiment of the present invention;

[0046] Figure 4 A schematic diagram of a process for measuring indirect carbon emissions in a method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection provided by an embodiment of the present invention;

[0047] Figure 5 A schematic diagram of a process for measuring extended carbon emissions in a method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection provided by an embodiment of the present invention;

[0048] Figure 6 A schematic diagram of a flow chart of calculating emission factors based on actual measurements in a method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection provided in an embodiment of the present invention;

[0049] Figure 7A logical schematic diagram of automatically selecting a sensor with a suitable range in a method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection provided by an embodiment of the present invention;

[0050] Figure 8 A schematic diagram of the overall structure of a carbon emission metering device for a sewage treatment plant based on greenhouse gas detection provided by an embodiment of the present invention;

[0051] Fig. 9 A schematic diagram of the proportion of each emission type obtained by a measurement method based on first production data and emission factors in a method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection provided by an embodiment of the present invention;

[0052] Fig.10 A schematic diagram of the proportion of each carbon emission amount to the total carbon emission amount obtained based on the actual measurement method in the carbon emission measurement method of a sewage treatment plant based on greenhouse gas detection provided by an embodiment of the present invention.

[0053] Reference numerals:

[0054] 1. Floating body; 2. Gas collecting cylinder; 3. Gas collection tube; 4. Dehumidification component; 5. Inlet valve; 6. Gas temperature / flow meter; 7. Air pump; 8. Diverter; 9. Pretreatment component; 10. Gas detection component; 11. Control component; 12. Wireless data collector; 13. Industrial computer. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0056] An embodiment of the present invention provides a method for measuring carbon emissions from sewage treatment plants based on greenhouse gas detection. The method uses two methods, namely actual measurement and emission factor-based measurement, to perform measurement respectively, and determines the measurement values ​​obtained by the two methods to use the more accurate one as the direct carbon emissions of the sewage treatment plant, thereby improving the accuracy of carbon emission measurement of the sewage treatment plant.

[0057] A method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection according to an embodiment of the present invention will first be described in detail below with reference to the accompanying drawings.

[0058] Specifically, Figure 1 As shown and in combination with Table 1 and Table 2 below, a method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection is provided in an embodiment of the present invention, comprising the following steps:

[0059] S1. Acquire gas data, where the gas data is data related to greenhouse gases generated in real time by a sewage treatment plant.

[0060] Greenhouse gases produced by sewage treatment plants mainly include CO 2 , CH 4 、N 2 O, are the three main greenhouse gases in the atmosphere. Greenhouse gas measurement is the basis for carbon emission measurement and accounting.

[0061] S2. Determine the measured direct carbon emission data based on the gas data.

[0062] Real-time greenhouse gas CO generated by wastewater treatment plants 2 For CO 2 Direct carbon emissions data.

[0063] CH in greenhouse gases generated by wastewater treatment plants in real time 4 、N 2 O is converted into CH 4 、N 2 ODirect carbon emission data. CO 2 , CH 4 and N 2 The greenhouse effect index of O is 1, 21 and 310 respectively, and the greenhouse effect index will also be specifically applied to the formula below for calculation.

[0064] According to step S1 and step S2, the direct carbon emission T is measured 实 It is calculated by the following formula:

[0065] T 实 =FCF*(T CO2，厌氧 +T CO2，好氧 )+T CO2，缺氧 +310*T N2O +21*T CH4

[0066] Among them, FCF is CO from fossil carbon. 2 Direct emission ratio, recommended value is 10%; T CO2，厌氧 For the anaerobic CO 2 Direct emissions; T CO2，好氧 For the aerobic CO 2 Direct emissions; T CO2，缺氧 Adding carbon source CO for anoxic denitrification 2 Direct emissions; T N2O Biochemical segment N 2 O Direct emissions; T CH4 Biochemical segment CH 4Direct emissions.

[0067] It should be noted that anoxic denitrification with an external carbon source CO 2 Direct emissions T CO2，缺氧 It should be the measured CO before and after adding carbon source 2 difference.

[0068] In one embodiment, the actual measurement of direct carbon emissions requires reasonable design of the detection points and the number of detection points. When multiple detection points are designed for the same detection indicator, the carbon emissions of the indicator are calculated by the following formula:

[0069] T x =[∑ n i＝0 (T xi ) / n]*(S1 / S0);

[0070] Wherein, T is the measured direct carbon emission data, x is the gas data, i is the number of the ith detection point, n is the total number of detection points, S0 is the effective area of ​​a gas collection device of the detection device, and S1 is the total area of ​​the detection area.

[0071] S3, obtaining the first production data required for direct carbon emission measurement and obtaining the emission factor corresponding to the first production data, wherein the first production data includes anaerobic bioreactor data, aerobic bioreactor data, denitrification added carbon source data, N 2 O data and CH 4 Any one or more of the data.

[0072] First, production data is collected directly online through a wireless production data collection system, and emission factors are derived from an emission factor database.

[0073] S4. Determine and calculate direct carbon emission data based on the first production data and the corresponding emission factors.

[0074] Since the IPCC guidelines ignore the emissions of carbon dioxide during biochemical reactions and do not provide an accounting method for carbon dioxide from fossil sources, the accuracy of carbon emission measurements by sewage treatment plants is greatly reduced.

[0075] Based on this, the embodiment of the present invention determines the anaerobic fossil carbon emission M according to the Monteith static model and the stoichiometric relationship. CO2，厌氧 and good oxidized fossil carbon emissions M CO2，好氧 .

[0076] Among them, the anaerobic biological treatment process of the sewage plant is the fossil source CO produced by organic carbon reduction and endogenous metabolism of microorganisms. 2 Direct emissions (kgCO 2 / d) and is calculated by the following formula:

[0077] M CO2，厌氧 =FCF*[0.27Q(CODo-CODe)*10 -3 +0.58Q*HRT*MLVSS*K d *10 -3 ];

[0078] Among them, FCF is CO from fossil carbon. 2 Direct discharge ratio, recommended value is 10%; Q is the influent flow rate of the anaerobic biological reactor, m 3 / d; CODo and CODe are the COD of the inlet and outlet water of the anaerobic biological reactor, mg / L; HRT is the hydraulic retention time of the anaerobic biological tank, d; MLVSS is the average concentration of volatile suspended solids in the mixed liquor of the anaerobic biological tank, mg / L; K d is the attenuation coefficient, d -1 , the recommended value is 0.05.

[0079] Fossil CO generated during aerobic treatment 2 Direct emissions (kgCO 2 / d) and is calculated by the following formula:

[0080] M CO2，好氧 =

[0081] FCF*[(1.1aQ-1.1cyY)(CODo-CODe)*10 -3 +1.947Q*HRT*MLVSS*Kd*10 -3 ];

[0082] Among them, parameter a is the oxygen equivalent of carbon, which is 1.47; parameter c is the oxygen equivalent of bacterial cells, which is 1.42; Q is the influent flow rate of the aerobic bioreactor, m 3 / d; CODo and CODe are the COD of the inlet and outlet water of the aerobic biological reactor, mg / L; parameter y is the MLVSS / MLSS value of the aerobic biological reactor; Y is the sludge yield coefficient of the aerobic tank, kg MLVSS / kg BOD5, and the recommended value is 0.68; HRT is the hydraulic retention time of the aerobic biological tank, d; MLVSS is the average concentration of volatile suspended solids in the mixed liquor of the aerobic biological tank, mg / L; Kd is the attenuation coefficient, d -1 , the recommended value is 0.05.

[0083] Next, we will calculate the denitrification additional carbon source data, N 2 O data and CH 4 data.

[0084] Specifically, the carbon data M of the denitrification added carbon source in the denitrification process of sewage treatmentCO2,外加碳源 It is calculated by the following formula:

[0085] M CO2,外加碳源 =EF CO2 *M 外加碳源 ;

[0086] Among them, EF CO2 The amount of carbon source added is determined by the type of carbon source added and is oxidized to CO 2 Emission factor, kgCO 2 / kg; M 外加碳源 is the dosage of external carbon source, kg / d.

[0087] Furthermore, the removal of TN produced during wastewater treatment 2 O direct emissions (kgCO 2 / d) is calculated by the following formula:

[0088] M N2O =310*[(Q(TNo-TNe) / 10 -3 )×EF N2O ×44 / 28];

[0089] Among them, Q is the daily water treatment volume of the sewage treatment plant, m 3 / d; TNo and TNe are the total nitrogen concentrations of influent and effluent, mg / L; EF N2O The unit mass of nitrogen in sewage can be converted into N 2 The amount of nitrogen in O, i.e. N 2 O emission factor, recommended value is 0.005kgN 2 ON / kgN 2 -N.

[0090] Furthermore, the CH generated by COD removal during sewage treatment 4 Direct emissions (kgCO 2 / d) is calculated by the following formula:

[0091] M CH4 =21×[Q*(CODo-CODe)*10 -3 *EF CH4 ];

[0092] Among them, Q is the daily treatment flow of the sewage plant, m 3 / d; CODo and CODe are the COD concentrations of the sewage treatment plant’s inlet and outlet water, mg / L; EF CH4 is the methane emission factor selected according to the treatment pathway, kgCH 4 / kgCOD.

[0093] In the above calculation steps, the direct carbon emission data of the sewage treatment plant include anaerobic fossil carbon emission, aerobic fossil carbon emission, denitrification carbon emission, Ez = M CO2，厌氧 +M CO2，好氧 +M CO2,外加碳源 +M N2O + M CH4 .

[0094] S5. Determine the direct carbon emissions of the sewage treatment plant based on the measured direct carbon emissions data and the calculated direct carbon emissions data.

[0095] That is, this step further determines a more accurate direct carbon emission amount of the sewage treatment plant based on the measured direct carbon emission data and the calculated direct carbon emission data, so as to improve the accuracy of the carbon emission measurement of the sewage treatment plant.

[0096] Further, such as Figure 2 As shown, step S5 also includes the steps of:

[0097] S51. Determine whether the difference between the measured direct carbon emission data and the calculated direct carbon emission data is greater than a threshold.

[0098] S52: when the value is less than or equal to the threshold, the larger value between the measured direct carbon emission data and the calculated direct carbon emission data is used as the direct carbon emission amount;

[0099] S53: When the value is greater than the threshold, the uncertainties of the measured direct carbon emission data and the calculated direct carbon emission data are determined according to the uncertainty model respectively, and the one with the smaller uncertainty is used as the direct carbon emission amount.

[0100] There will be a deviation between the measured direct carbon emissions data and the calculated direct carbon emissions data. If the deviation is small and within the threshold range, it is normal. If the deviation is large, it means that there is a problem with the measured direct carbon emissions data or the calculated direct carbon emissions data. This step uses the uncertainty model to obtain a more accurate direct carbon emissions amount.

[0101] Furthermore, the uncertainty model includes a first uncertainty model and a second uncertainty model, the first uncertainty model is used to determine the uncertainty of the measured direct carbon emission data, and the second uncertainty model is used to determine the uncertainty of the calculated direct carbon emission data, wherein the first uncertainty model is constructed based on the uncertainty of the gas data source, and the second uncertainty model is constructed based on the first production data source.

[0102] Specifically, Figure 3 As shown, the specific steps of how to construct the first uncertainty model and the second uncertainty model are as follows:

[0103] S531. Determine the sources of uncertainty.

[0104] The sources of uncertainty in measured direct carbon emission data include missing data, unrepresentative data (such as the choice of emission factors), non-standard data sources, etc. The sources of uncertainty in calculated direct carbon emission data include flow measurement, greenhouse gas concentration measurement, unrepresentative sampling, analytical instrument performance, etc.

[0105] S532. Determine the uncertainty of each source of uncertainty.

[0106] The uncertainty of each uncertainty source is determined or calculated from the corresponding literature, management, reports, specifications and standards.

[0107] S533. Construct a first uncertainty analysis model and a second uncertainty analysis model.

[0108] The first uncertainty analysis model is:

[0109]

[0110] Among them, u 实 is the uncertainty of measured carbon emissions, u Q is the flow measurement uncertainty, is the CO2 measurement uncertainty, is the CH4 measurement uncertainty, is the measurement uncertainty of N2O.

[0111] The second uncertainty analysis model is:

[0112]

[0113] Among them, u 核 To calculate the uncertainty of direct carbon emissions, u 1 is the uncertainty of the first uncertainty source, such as flow measurement; u 2 is the uncertainty of the second uncertainty source, such as COD concentration measurement; u n is the uncertainty of the nth uncertainty source, such as the attenuation coefficient.

[0114] The u obtained by the first uncertainty analysis model and the second uncertainty analysis model 实 and u 核 , and compare the two. When u 核 >u 实 When T 实 is the recommended value, i.e., calculating direct carbon emission data; when u 核 <u 实When Ez is the recommended value, it is the actual measured direct carbon emission data.

[0115] In one embodiment, if Figure 4 As shown, after step S5, the following steps are also included:

[0116] S61. Acquire second production data required for indirect carbon emission measurement, where the second production data includes one or more of electricity data and wastewater discharge data.

[0117] S62. Obtain an emission factor corresponding to the second production data.

[0118] S63. Obtain indirect carbon emissions based on the second production data and its corresponding emission factor.

[0119] Specifically, the carbon emissions from electricity during sewage treatment, i.e., the electricity data M 电力 The calculation formula is as follows:

[0120] M 电力 =Se*Q*EF 电力 ;

[0121] Among them, Se is the power consumption per ton of water, kWh / m 3 ; Q is the daily treatment flow of the sewage plant, m 3 / d;EF 电力 is the regional electricity emission factor selected according to the location of the sewage treatment plant, kgCO 2 / kWh.

[0122] Furthermore, the carbon emissions from wastewater during sewage treatment, i.e., the wastewater discharge data M 排污 Including N 2 O indirect emissions and CH 4 Indirect emissions.

[0123] N generated during wastewater discharge 2 O indirect emissions (kgCO 2 / d) is calculated by the following formula:

[0124] M N2O，排污 =310*(M TNe ×EF N2O ×44 / 28);

[0125] Among them, M TNe is the TN discharge of the sewage treatment plant, kg / d; EF N2O It is the amount of nitrogen that can be converted into N2O per unit mass of nitrogen in sewage, that is, the N2O emission factor. The recommended value is 0.005kgN2O-N / kgN2-N.

[0126] CH generated during wastewater discharge4 Indirect emissions (kgCO 2 / d) is calculated by the following formula:

[0127] M CH4，排污 =21×(M CODe *EF CH4 );

[0128] Among them, M CODe is the COD discharge of the sewage treatment plant, kg / d; EF CH4 is the methane emission factor selected according to the treatment approach.

[0129] Therefore, the indirect carbon emissions from the sewage treatment plant are calculated by the following formula:

[0130] Ej=M 电力 +M N2O，排污 +M CH4，排污 .

[0131] In one embodiment, if Figure 5 As shown, after step S5, the following steps are also included:

[0132] S71. Acquire third production data required for extended carbon emission measurement, where the third production data includes one or more of pharmaceutical production data and vehicle transportation data.

[0133] S72. Obtain an emission factor corresponding to the third production data.

[0134] S73. Obtain extended carbon emissions based on the third production data and its corresponding emission factor.

[0135] Extended carbon emissions include pharmaceutical production data and vehicle transportation data.

[0136] Among them, the carbon emissions from pharmaceutical production during sewage treatment, i.e., pharmaceutical production data, are calculated using the following formula:

[0137] M CO2,药剂生产 =∑ n i=0(M 药剂用量 *EF 药剂生产 )i;

[0138] Among them, M 药剂用量 is the daily consumption of chemicals in the sewage treatment plant, kg / d; i is the number of chemical types, including carbon sources, phosphorus removal chemicals, disinfectants, etc.; EF 药剂生产 is the emission factor of pharmaceutical production determined according to the type of pharmaceutical, kgCO 2 / kg.

[0139] The transportation carbon emissions during sewage treatment, i.e., vehicle transportation data, are calculated using the following formula:

[0140] M CO2,运输 =D 运输 *FC*Q 油 *EF 燃油 ;

[0141] Among them, D 运输 is the vehicle transportation distance, km / d; FC is the fuel consumption per 100 kilometers, L / 100km; Q 油 is the calorific value of oil determined according to the type of oil, MJ / L; EF 燃油 It is the oil emission factor determined according to the oil type, g / MJ.

[0142] Therefore, the extended carbon emissions of the sewage treatment plant are obtained by the following formula:

[0143] Ey=M CO2,药剂生产 +M CO2,运输 .

[0144] Through the above examples, it can be obtained as shown in Table 1 and Table 2:

[0145] The total carbon emissions of the wastewater treatment plant determined by the greenhouse gases produced in real time are:

[0146] E 总 =T 实 +Ei+Ey.

[0147] The total carbon emissions of the sewage treatment plant determined by the first production data and the corresponding emission factor are:

[0148] E 总 '=Ez+Ei+Ey.

[0149]

[0150] Table 1

[0151]

[0152] Table 2

[0153] The above embodiments are summarized in Table 1 and Table 2. It can be seen from Table 1 and Table 2 that the difference between the two carbon emission measurement methods lies in the measurement of direct carbon emission data. The direct carbon emission data in Table 1 consists of fossil carbon emissions and greenhouse gas carbon emissions. Among them, fossil carbon emissions are calculated by the first production data and the model through the formula, plus carbon source carbon emissions, N 2 O carbon emissions and CH 4 Carbon emissions are calculated based on the first production data and emission factors.

[0154] The measured direct carbon emission data in Table 2 are obtained by real-time detection by the on-site gas detection device. The indirect carbon emissions and extended carbon emissions in Tables 1 and 2 are calculated based on production data and emission factors. By measuring indirect carbon emissions and extended carbon emissions, the accuracy of carbon emission measurement in sewage treatment plants can be improved.

[0155] After obtaining the calculated direct carbon emission data and the measured direct carbon emission data through two measurement methods, the two sets of data are further analyzed and processed to obtain a more accurate set of data, so as to improve the accuracy of carbon emission measurement of sewage treatment plants.

[0156] In one embodiment, after step S5, the method further includes the following steps:

[0157] S8. Use the measured direct carbon emission data to calibrate the emission factors in the emission factor data, and form a localized calibration emission factor database.

[0158] That is to say, the measured direct carbon emission data obtained by actual measurement without abnormalities is more accurate than the calculated direct carbon emission data. Based on the measured direct carbon emission data, the emission factors are designed and calculated, and verified with the default values ​​in the emission factor database to form a localized verification emission factor database, so that the emission factors in the localized verification emission factor database can be used in subsequent carbon emission measurement to improve the accuracy of carbon emission measurement.

[0159] Furthermore, step S8 also includes:

[0160] Based on different conditions, multiple values ​​are stored corresponding to the same emission factor in the localized verification emission factor database; wherein the different conditions include any one or more of the sewage treatment process, the sewage treatment scale, and the current temperature during sewage treatment.

[0161] In other words, the measurement of carbon emissions corresponds to different emission factors in different scenarios. For example, different treatment processes such as AAO, MBR, oxidation ditch, etc. will correspond to different emission factors, so as to obtain carbon emissions more accurately.

[0162] Further, such as Figure 6 As shown, the specific steps are as follows:

[0163] S81. Based on actual measurements, the total greenhouse gas emissions of the sewage treatment plant are calculated and obtained, Ei, where i represents the pollutant, i.e. CO 2 , CH 4 、N 2 O, greenhouse gases including CO 2 , CH 4 、N 2 O.

[0164] S82. Obtain the fourth production data of the sewage treatment plant required, where the fourth production data includes any one or more of the water treatment volume Q, the influent and effluent COD concentrations CODo and CODe, the external carbon source dosage M 外加碳源 and the COD equivalent coefficient I.

[0165] S83. Based on the process section and the fourth production data, calculate the removal amount of active data COD. The specific calculation formula is as follows:

[0166] ΔCOD = (CODo - CODe) * Q * 10 -3 + M 外加碳源 * I.

[0167] S84. Divide the total emission amount of greenhouse gases by the removal amount of active data COD to obtain the emission factor. That is:

[0168] EFi = Ei / ΔCOD.

[0169] The emission factor calculated based on the measured method is more accurate, which is convenient for improving the accuracy of subsequent carbon emission measurement of the sewage treatment plant.

[0170] In one embodiment, as Figure 7 shown, automatically select a sensor with an appropriate range to obtain the relevant data of the greenhouse gases generated by the sewage treatment plant in real time.

[0171] Specifically, when the gas concentration detected by the first range sensor is greater than the maximum range of the first range sensor, the range of the first range sensor is 0 - appm; use the second range sensor to detect the gas, and the range of the second range sensor is 0 - bppm. When the gas concentration detected by the second range sensor is greater than the maximum range of the second range sensor, use the third range sensor to detect the gas, and the range of the first range sensor is 0 - cppm; until the detected gas concentration is within the range corresponding to the sensor. Among them, the maximum range corresponding to the first range sensor is less than the maximum range corresponding to the second range sensor, and the maximum range corresponding to the second range sensor is less than the maximum range corresponding to the third range sensor, that is, a < b < c. This detection method can cover the greenhouse gas concentration ranges at different points and different concentrations in the sewage treatment plant, improving the accuracy of greenhouse gas detection in the sewage treatment plant.

[0172] The embodiment of the present invention also provides a carbon emission measurement device for a sewage treatment plant based on greenhouse gas detection, as Figure 8 shown, including an on-line gas detection system, a production data acquisition system, and an industrial control computer 13.

[0173] Among them, the online gas detection system is used to detect the greenhouse gases generated by the sewage treatment plant in real time online and obtain gas data.

[0174] The production data acquisition system is used to collect the first production data required for direct carbon emission measurement of the sewage treatment plant in real time. The first production data includes anaerobic biological reactor data, aerobic biological reactor data, denitrification added carbon source data, N 2 O data and CH 4 Any one or more of the data.

[0175] The industrial computer 13 obtains the gas data and the first production data, and obtains the emission factor corresponding to the first production data, and determines and outputs the direct carbon emissions of the sewage treatment plant.

[0176] The device also includes a wireless data collector 12, which is connected to an industrial computer 13, so that the production data collection system uses wireless data collection to collect data in real time, and collects data required for carbon emissions from the sewage treatment plant. The collected data includes the daily processing flow of the sewage treatment plant, power consumption per ton of water, COD and TN concentrations of inlet and outlet water, chemical consumption, fuel consumption per 100 kilometers of transport vehicles, and transportation distance.

[0177] The industrial computer 13 includes a data transmission system, a database and an algorithm. The data transmission system is used to transmit data detected by the online gas detection system and data collected by the production data collection system. The database includes an online collection database, an online detection database and an emission factor database. The algorithm is used to measure the overall carbon emissions of the sewage treatment plant.

[0178] The carbon emission metering device in the embodiment of the present invention is low-cost, occupies a small space, has flexible deployment and is easy to operate. It meets the wide range of carbon emission detection requirements of sewage treatment plants. It is combined with a wireless data collection system to realize real-time online transmission of generated data, thereby realizing real-time online detection of carbon emissions in sewage treatment plants, filling the gap in carbon emission metering devices for sewage treatment plants.

[0179] In one embodiment, the online gas detection system includes a gas collection component, a gas collection pipe 3 and a gas detection component 10. The gas collection component is used to collect greenhouse gases generated in real time by the sewage treatment plant. The gas detection component 10 is used to detect the range of the collected greenhouse gases. The gas collection pipe 3 connects the gas collection component and the gas detection component 10.

[0180] Furthermore, the gas collection assembly includes a float 1, a gas collecting cylinder 2, an air inlet valve 5, a gas temperature / flow meter 6 and an air pump 7. The float 1 is fixedly connected to the gas collecting cylinder 2, and the float 1 is used to provide buoyancy for the gas collecting cylinder 2 and maintain its balance. The gas collecting cylinder 2 is a cylindrical structure with an open bottom. The bottom end of the gas collecting cylinder 2 is located below the liquid level of the sewage pool and allows space above the liquid level in the gas collecting cylinder 2 for collecting greenhouse gases.

[0181] One end of the gas collection pipe 3 is connected to the bottom end of the gas collecting cylinder 2 and is connected to the air inlet valve 5, the gas temperature / flow meter 6 and the air pump 7 in sequence.

[0182] The air intake valve 5 is used to open or close the air intake, and the air intake valve 5 can be remotely controlled. The gas temperature / flow meter 6 is used to measure the generated gas temperature / flow. The air pump 7 is used to discharge the original gas in the gas collection cylinder 2, and the gas collection flow rate is preferably 0-4L / min. Before using the gas collection cylinder 2 to collect gas, the gas in the gas collection cylinder 2 is first exhausted by the air pump 7 before collecting, so as to improve the accuracy of gas collection.

[0183] Furthermore, a flow divider 8 is connected between the air pump 7 and the gas detection assembly 10, and the flow divider 8 is used for multi-point sampling or the introduction of diluted gas.

[0184] Furthermore, the float 1 is preferably a foam board and is fixedly connected to the outer wall of the gas collecting cylinder 2 and is located at a distance upward from the bottom end of the gas collecting cylinder 2, such as 10 cm, but is certainly not limited to this exemplary distance.

[0185] In one embodiment, the gas detection assembly 10 includes three sets of CO 2 , CH 4 、N 2 O detection sensor matrix, where CO 2 The detection principle is infrared detection, CH 4 The detection principle is MOS, N 2 The detection principle of O is optical waveguide detection. The measuring range of CO2 is: 0-5000ppm, 0-10000ppm, 0-15000ppm; CH 4 The measuring range is: 0-40ppm, 0-100ppm, 0-200ppm; N 2 The measurement range of O is: 0-5ppm, 0-10ppm, 0-30ppm. The size of the gas detection component 10 is about: 10cmx10cmx15cm. The detection sensors with multiple measurement ranges cover the concentration ranges of greenhouse gases at different points in the sewage treatment plant with different concentrations, thereby improving the accuracy of greenhouse gas detection in the sewage treatment plant.

[0186] In one embodiment, the device also includes a control component 11, which is used to automatically control the greenhouse gas detection component 10 to select a detection sensor with a suitable range at different detection points, and is used to automatically control the start and stop of the intake valve 5, automatically control the start and stop of the air pump 7, and automatically control the start and close of each straight pipe of the diverter 8.

[0187] In one embodiment, the device also includes a dehumidification component 4, which is located between the gas collecting cylinder 2 and the air inlet valve 5. The dehumidification component 4 is used to remove humidity from the greenhouse gas to ensure that the gas humidity of the gas detection component 10 is less than or equal to 95% RH without condensation. Dehumidifying the gas can not only improve the accuracy of gas detection, but also extend the service life of the gas detection sensor.

[0188] Multiple gas detection components 10 and dehumidification components 4 in the device are configured according to needs, and configuring multiple gas detection components 10 and dehumidification components 4 can meet the requirements of dilution gas introduction, realize multi-point greenhouse gas sequential detection, and single-point greenhouse gas multi-sample detection and average value, so as to improve detection accuracy.

[0189] In one embodiment, if Figure 8 As shown, Figure 8 The float 1, gas collecting cylinder 2, gas collection pipe 3, dehumidification component 4, air intake valve 5, gas temperature / flow meter 6 and air pump 7 are integrated into a pre-processing component 9, that is, the diverter 8 can be connected to multiple pre-processing components 9 at the same time, and the average value of multiple pre-processing components 9 is taken to improve the detection accuracy.

[0190] A specific example of using the sewage treatment plant carbon emission metering device based on greenhouse gas detection provided by the present invention to measure carbon emissions from a certain urban sewage treatment plant is as follows:

[0191] A certain urban sewage treatment plant adopts multi-stage AAO process, and the effluent quality complies with the Class A standard of Pollutant Discharge Standard for Urban Sewage Treatment Plants GB 18918-2002. The design scale is 400,000 tons / day, the treatment load rate is about 95%, and the anaerobic area of ​​the biological reactor is 610.7m 2 、The hypoxic area is 2198.6m 2 、Aerobic Zone 1 area: 2809.3m 2 、Aerobic 2 area 3420m 2 The plant design parameters, operating parameters, online acquisition data, etc. are shown in Table 3.

[0192]

[0193] Table 3

[0194] The water quality and operation data of the sewage treatment plant are applied to the measurement method based on the first production data and emission factors in the carbon emission measurement method for sewage treatment plants based on greenhouse gas detection provided by the present invention to obtain the total carbon emissions of the sewage treatment plant, as shown in Figure 4. The proportion of each emission type is shown in Figure 9.

[0195]

[0196] Table 4

[0197] As shown in Table 4, the carbon emissions of the urban sewage treatment plant are 202079.85 kgCO 2 / d, of which direct carbon emissions are 120329.6kgCO 2 / d, indirect carbon emissions are 63259.16kgCO 2 / d, the extended carbon emissions are 18491.09kgCO 2 / d. The total carbon emission intensity is 0.534kgCO 2 / m3·d.

[0198] The CO2 emitted from the biochemical pool is measured by the actual measurement method in the method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection provided by the present invention. 2 , CH 4 、N 2 The concentration of O is shown in Table 5. The carbon emissions calculated by the algorithm account for the proportion of total carbon emissions. Fig.10 As shown, fossil carbon emissions account for 2%, and CH 4 Carbon emissions account for 35%, producing N 2 O accounts for 63% of carbon emissions. 2 O has a large warming potential.

[0199]

[0200] Table 5

[0201] The embodiments of the present invention provide a method and device for measuring carbon emissions from sewage treatment plants based on greenhouse gas detection. The method targets the limitations of emission factors and combines specific detection methods for greenhouse gases to measure the carbon emissions of sewage treatment plants using two separate measurement methods. The carbon emissions measured separately are then nucleic acid-labeled to improve the accuracy of carbon emission measurement at sewage treatment plants. In addition, the device provides a basic tool for carbon emission reduction in sewage treatment plants and is of great significance to the realization of carbon peak and carbon neutrality goals at sewage treatment plants.

[0202] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for measuring carbon emissions from a sewage treatment plant based on greenhouse gas detection, characterized in that: include: Acquire gas data, where the gas data is data related to greenhouse gases generated in real time by the sewage treatment plant; determining measured direct carbon emission data based on the gas data; Obtaining first production data required for direct carbon emission measurement and obtaining emission factors corresponding to the first production data, wherein the first production data includes any one or more of anaerobic bioreactor data, aerobic bioreactor data, denitrification added carbon source data, N2O data, and CH4 data; Determine and calculate direct carbon emission data based on the first production data and the corresponding emission factor; Determining the direct carbon emissions of the sewage treatment plant based on the measured direct carbon emissions data and the calculated direct carbon emissions data; Also includes: The measured direct carbon emission data is used to calibrate the emission factors in the emission factor data, and a localized calibration emission factor database is formed. The specific steps are as follows: Based on the actual measurement method, the total greenhouse gas emissions Ei of the sewage treatment plant are calculated respectively, where i represents the pollutant, namely CO2, CH4, N2O, and greenhouse gases include CO2, CH4, and N2O; Obtain the fourth production data of the required sewage treatment plant, the fourth production data includes the treated water volume Q, the inlet and outlet COD concentrations CODo and CODe, and the external carbon source dosage M 外加碳源 and any one or more of the COD equivalent coefficient I; Based on the process stage and the fourth production data, the removal amount of COD in the activity data is calculated, and the specific calculation formula is as follows: ΔCOD=(CODo-CODe)*Q*10 -3 +M 外加碳源 *I; Calculate the ratio of total greenhouse gas emissions to the removal of COD from activity data to obtain the emission factor, which is: EFi = Ei / ΔCOD; Based on the measured direct carbon emission data and the calculated direct carbon emission data, determining the direct carbon emission of the sewage treatment plant includes: Determine whether the difference between the measured direct carbon emission data and the calculated direct carbon emission data is greater than a threshold, When it is less than or equal to the threshold, the larger value between the measured direct carbon emission data and the calculated direct carbon emission data is used as the direct carbon emission amount; When it is greater than the threshold, the uncertainty of the measured direct carbon emission data and the calculated direct carbon emission data are determined according to the uncertainty model respectively, and the one with the smaller uncertainty is taken as the direct carbon emission amount; The uncertainty model includes a first uncertainty model and a second uncertainty model. The first uncertainty model is used to determine the uncertainty of the measured direct carbon emission data, and the second uncertainty model is used to determine the uncertainty of the calculated direct carbon emission data. The first uncertainty model is constructed based on the uncertainty of the gas data source, and the second uncertainty model is constructed based on the first production data source.

2. The method according to claim 1, characterized in that The gas data comes from multiple detection points, wherein determining the measured direct carbon emission data based on the gas data includes: T x =[∑ n i=0 (T xi ) / n]*(S1 / S0); Among them, T is the measured direct carbon emission data, x is the gas data, i is the i-th detection point number, n is the total number of detection points, S0 is the effective area of ​​a gas collection device of the detection device, and S1 is the total area of ​​the detection area.

3. The method according to claim 1, characterized in that Also includes: Acquire second production data required for indirect carbon emission measurement, where the second production data includes one or more of power data and wastewater discharge data; Obtaining an emission factor corresponding to the second production data; According to the second production data and its corresponding emission factor, indirect carbon emissions are obtained.

4. The method according to claim 1, characterized in that Also includes: Acquire third production data required for extended carbon emission measurement, wherein the third production data includes one or more of pharmaceutical production data and vehicle transportation data; Obtaining an emission factor corresponding to the third production data; The extended carbon emissions are obtained according to the third production data and its corresponding emission factor.

5. The method according to claim 1, characterized in that Using the measured direct carbon emission data to calibrate the emission factors in the emission factor data and form a localized calibration emission factor database includes: Based on different conditions, multiple values ​​are stored corresponding to the same emission factor in the localized verification emission factor database; wherein the different conditions include any one or more of the sewage treatment process, the sewage treatment scale, and the current temperature during sewage treatment.

6. A carbon emission metering device for a sewage treatment plant based on greenhouse gas detection, characterized in that: include: An online gas detection system, used for online detection of greenhouse gases generated in real time by a sewage treatment plant, obtaining gas data, and determining measured direct carbon emission data based on the gas data; A production data collection system, used for collecting in real time the first production data required for direct carbon emission measurement of the sewage treatment plant, wherein the first production data includes any one or more of anaerobic biological reactor data, aerobic biological reactor data, denitrification added carbon source data, N2O data and CH4 data; The industrial computer obtains the gas data and the first production data, obtains the emission factor corresponding to the first production data, determines and outputs the direct carbon emissions of the sewage treatment plant, uses the measured direct carbon emissions data to calibrate the emission factors in the emission factor data, and forms a localized calibration emission factor database, and the specific steps are as follows: Based on the actual measurement method, the total greenhouse gas emissions Ei of the sewage treatment plant are calculated respectively, where i represents the pollutant, namely CO2, CH4, N2O, and greenhouse gases include CO2, CH4, and N2O; Obtain the fourth production data of the required sewage treatment plant, the fourth production data includes the treated water volume Q, the inlet and outlet COD concentrations CODo and CODe, and the external carbon source dosage M 外加碳源 and any one or more of the COD equivalent coefficient I; Based on the process stage and the fourth production data, the removal amount of COD in the activity data is calculated, and the specific calculation formula is as follows: ΔCOD=(CODo-CODe)*Q*10 -3 +M 外加碳源 *I; Calculate the ratio of total greenhouse gas emissions to the removal of COD from activity data to obtain the emission factor, which is: EFi = Ei / ΔCOD; Wherein, it is determined whether the difference between the measured direct carbon emission data and the calculated direct carbon emission data is greater than a threshold value, When it is less than or equal to the threshold, the larger value between the measured direct carbon emission data and the calculated direct carbon emission data is used as the direct carbon emission amount; When it is greater than the threshold, the uncertainty of the measured direct carbon emission data and the calculated direct carbon emission data are determined according to the uncertainty model respectively, and the one with the smaller uncertainty is taken as the direct carbon emission amount; The uncertainty model includes a first uncertainty model and a second uncertainty model. The first uncertainty model is used to determine the uncertainty of the measured direct carbon emission data, and the second uncertainty model is used to determine the uncertainty of the calculated direct carbon emission data. The first uncertainty model is constructed based on the uncertainty of the gas data source, and the second uncertainty model is constructed based on the first production data source.

7. The device according to claim 6, characterized in that The online gas detection system comprises: Gas collection components, used to collect greenhouse gases generated in real time by sewage treatment plants; A gas detection component for detecting the concentration of collected greenhouse gases; The gas collection tube is connected between the gas collection component and the gas detection component.

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