Accounting method for carbon emission in operation and maintenance period of rainwater drainage system

Abstract

The invention discloses an accounting method for carbon emission in an operation and maintenance period of a rainwater drainage system. The accounting method comprises the following steps: 1, acquiring basic data; 2, according to different rainwater drainage modes, constructing an accounting formula about the carbon emission in the operation and maintenance period of the rainwater drainage system and the whole-process emission capability; 3, carrying out generalization and uncertainty setting on parameters in the accounting formula; and 4, simulating the carbon emission in the operation and maintenance period of the rainwater drainage system and the whole-process emission capacity based on the uncertainty of the parameters, and summarizing and reporting simulation results. The application of the invention can make the calculation of the carbon emission in the operation and maintenance period of the rainwater drainage system and the whole-process emission capability more objective, comprehensive and reliable.

Description

Technical Field

[0001] The present invention relates to the field of computer-aided technology, and particularly to a method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system. Background Art

[0002] Due to the accelerating urbanization process and the impact of global climate change, problems such as frequent extreme weather, urban waterlogging, and initial rainwater pollution have become increasingly prominent, and urban rainwater management systems are also constantly updated and upgraded.

[0003] In practical applications, the gray rainwater drainage system composed of rainwater collection facilities, rainwater pipelines, rainwater pumping stations, storage ponds, etc., and the green rainwater drainage system composed of rainwater infiltration facilities, rainwater ponds, biological and ecological purification facilities, etc., together constitute the urban rainwater drainage system. Many different technical measures and operation links in the rainwater system may generate more energy consumption and carbon emissions, and the ecological low-impact measures among them may also play a certain carbon emission reduction benefit through the way of carbon sinks.

[0004] At present, the following problems exist in the calculation methods for carbon emissions of rainwater drainage systems:

[0005] (1) The boundary of carbon emission calculation is not clear. The research on the operation and maintenance period is often only limited to the electricity consumption generated during the rainwater transportation and discharge process, and little consideration is given to the carbon emissions generated after the initial rain runoff carrying a large amount of pollutants enters the receiving water body and is discharged.

[0006] (2) The calculation differences of different rainwater drainage modes are not fully considered, and no carbon emission capacity index (factor) that is convenient for calculation and integrates the whole process is provided.

[0007] (3) The uncertainty of statistical quantities such as rainwater runoff and biochemical reaction parameters is not fully considered, but often only a single value (such as the mean value) or a simple range value (such as the minimum value - maximum value) is taken from the statistical information for calculation.

[0008] Therefore, how to make the calculation of carbon emissions during the operation and maintenance period of the rainwater drainage system and the whole-process emission capacity more objective, comprehensive, and reliable has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0009] In view of the above-mentioned defects of the prior art, the present invention provides a method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system, and the achieved purpose is to make the calculation of carbon emissions during the operation and maintenance period of the rainwater drainage system and the whole-process emission capacity more objective, comprehensive, and reliable.

[0010] To achieve the above purpose, the present invention discloses a method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system, including the following steps:

[0011] Step 1: Obtain basic data;

[0012] Step 2: Construct calculation formulas for carbon emissions during the operation period and the carbon emission capacity throughout the whole process of the rainwater drainage system according to different rainwater drainage modes;

[0013] Step 3: Generalize the parameters in the calculation formula and set the uncertainties;

[0014] Step 4: Simulate the carbon emissions during the operation period and the carbon emission capacity throughout the whole process of the rainwater drainage system based on the uncertainties of the parameters, and summarize and report the simulation results.

[0015] Preferably, in Step 1, the basic data includes the volume V of the existing rainwater storage tank z , the total rainfall volume Q T and its minimum, maximum and average values, the first flush runoff volume Q W and its minimum, maximum and average values, and the average value and standard deviation of the event concentrations of COD and TN corresponding to the first flush runoff volume Q W .

[0016] More preferably, in Step 2, when the rainwater drainage mode is the self-drainage mode, that is, the rainwater is directly discharged into the receiving water body by its own gravity, the specific calculation formulas for the carbon emissions during the operation period and the carbon emission capacity throughout the whole process are as follows:

[0017] TCE ZP = CE W ·Q T ;

[0018]

[0019] In the formula, TCE ZP is the carbon emission during the operation period in the self-drainage mode, with the unit of: kgCO 2 eq; CE ZP is the carbon emission capacity throughout the whole process in the self-drainage mode, with the unit of: kgCO 2 eq / m 3 ;

[0020] CE W is the direct carbon emission capacity caused by the discharge of the first flush runoff into the receiving water body, with the unit of kg CO 2 eq / m 3 , and the calculation formula is as follows:

[0021]

[0022] Among them, CE W_CH4 is the carbon emission capacity of CH 4 caused by the discharge of the first flush runoff into the receiving water body, with the unit of kgCO2 eq / m 3 , the calculation formula is as follows:

[0023] CE W_CH4 = COD r ·EF W_CH4 ·28;

[0024] Among them, COD r is the event concentration of COD corresponding to the initial rainwater runoff, with the unit: kg COD / m 3 ; EF W_CH4 is the CH 4 carbon emission factor caused by the discharge of the initial rainwater runoff into the receiving water body, with the unit kg CH 4 / kg COD; 28 is the global warming potential value of CH 4 , with the unit kg CO 2 eq / kg CH 4 ;

[0025] CE W_N2O is the N 2 O carbon emission capacity caused by the discharge of the initial rainwater runoff into the receiving water body, with the unit kgCO 2 eq / m 3 , and the calculation formula is as follows:

[0026]

[0027] Among them, TN r is the event concentration of TN corresponding to the initial rainwater runoff, with the unit kg COD / m 3 and kg N / m 3 ; EF W_N2O is the N 2 O carbon emission factor caused by the discharge of the initial rainwater runoff into the receiving water body, with the unit kg kg N 2 O / kg N; 265 is the global warming potential value of N 2 O, with the unit kg CO 2 eq / kg N 2 O; is the molecular mass ratio of 1 / 2N 2 O to N.

[0028] More preferably, in step 2, when the rainwater drainage mode is the storage mode, that is, the rainwater first passes through the rainwater storage tank and then is lifted to the sewage treatment plant by the rainwater pump station without being directly discharged into the receiving water body, the specific calculation formulas for the carbon emissions during the operation and maintenance period and the carbon emission capacity of the whole process are:

[0029] TCE TX =(CE E+CE X )·Q T ;

[0030]

[0031] In the formula, TCE TX is the carbon emission during the operation and maintenance period of the storage mode, with the unit of kg CO 2 eq; CE TX is the carbon emission capacity throughout the whole process of the storage mode, with the unit of kg CO 2 eq / m 3 ;

[0032] CE E is the indirect carbon emission capacity generated when all rainwater is lifted by the rainwater pumping station, with the unit of kg CO 2 eq / m 3 , and the calculation formula is as follows:

[0033] CE E = E d ·EF d ;

[0034] Among them, E d is the power consumption generated when lifting rainwater with a unit volume by the rainwater pumping station, with the unit of kWh / m 3 ; EF d is the regional power grid emission factor, with the unit of kg CO 2 eq / kWh;

[0035] CE X is the indirect carbon emission capacity generated during the operation and maintenance stage of the storage tank, with the unit of kg CO 2 eq / m 3 , and the calculation formula is as follows:

[0036]

[0037] In the formula, V X is the volume of the storage tank, with the unit of m 3 ; EF X is the indirect carbon emission factor generated during the operation and maintenance stage of the storage tank, with the unit of kg CO 2 eq / (m 3 ·a); T is the duration of the accounting time scale.

[0038] More preferably, in step 2, when the rainwater drainage mode is the strong drainage mode, that is, the rainwater first passes through the rainwater storage tank, and then is lifted by the rainwater pumping station and directly discharged into the receiving water body,, then the specific calculation formulas for the carbon emission during the operation and maintenance period and the carbon emission capacity throughout the whole process are:

[0039] TCEQP =(CE W +CE E +CE X )·Q T ;

[0040]

[0041] Wherein, TCE QP is the carbon emission during the operation and maintenance period in the forced ventilation mode, with the unit of kg CO 2 eq; CE QP is the carbon emission capacity throughout the whole process in the forced ventilation mode, with the unit of kg CO 2 eq / m 3 ;

[0042] CE W is the direct carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, with the unit of kg CO 2 eq / m 3 , and the calculation formula is as follows:

[0043]

[0044] Among them, CE W_CH4 is the CH 4 carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, with the unit of kgCO 2 eq / m 3 , and the calculation formula is as follows:

[0045] CE W_CH4 =COD r ·EF W_CH4 ·28;

[0046] Among them, COD r is the event concentration of COD corresponding to the initial rainwater runoff, with the unit of: kg COD / m 3 ; EF W_CH4 is the CH 4 carbon emission factor caused by the initial rainwater runoff discharged into the receiving water body, with the unit of kg CH 4 / kg COD; 28 is the global warming potential value of CH 4 , with the unit of kg CO 2 eq / kg CH 4 ;

[0047] CE W_N2O is the N 2 O carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, with the unit of kgCO 2 eq / m 3 , and the calculation formula is as follows:

[0048]

[0049] Among them, TN r The event concentration of TN corresponding to the initial rainwater runoff, with the unit of kg COD / m 3 And kg N / m 3 ; EF W_N2O Is the N 2 O carbon emission factor caused by the discharge of the initial rainwater runoff into the receiving water body, with the unit of kg kg N 2 O / kg N; 265 is the global warming potential value of N 2 O, with the unit of kg CO 2 eq / kg N 2 O; Is the molecular mass ratio of 1 / 2N 2 O to N;

[0050] CE E Is the indirect carbon emission capacity generated when all rainwater is lifted by the rainwater pumping station, with the unit of kg CO 2 eq / m 3 , and the calculation formula is as follows:

[0051] CE E =E d ·EF d ;

[0052] Among them, E d Is the power consumption generated when lifting rainwater per unit volume by the rainwater pumping station, with the unit of kWh / m 3 ; EF d Is the regional power grid emission factor, with the unit of kg CO 2 eq / kWh;

[0053] CE X Is the indirect carbon emission capacity generated during the operation and maintenance stage of the storage tank, with the unit of kg CO 2 eq / m 3 , and the calculation formula is as follows:

[0054]

[0055] In the formula, V X Is the volume of the storage tank, with the unit of m 3 ; EF X Is the indirect carbon emission factor generated during the operation and maintenance stage of the storage tank, with the unit of kg CO 2 eq / (m 3 ·a); T is the duration of the accounting time scale.

[0056] More preferably, in step 3, for all the rainwater volume Q T 、the initial rain runoff volume Q W 、the initial rain runoff volume Q W corresponding event concentrations of COD, event concentrations of TN, CH 4 carbon emission factor EF W_CH4 caused by the discharge of the initial rain runoff into the receiving water body, and N 2 O carbon emission factor EF W_N2O 、the power consumption E generated when lifting rainwater per unit volume through a rainwater pumping station d 、the indirect carbon emission factor EF generated during the operation and maintenance stage of the storage tank X are generalized and uncertainty is set in the form of random variables.

[0057] More preferably, in step 3, for all the rainwater volume Q T 、the initial rain runoff volume Q W 、the initial rain runoff volume Q W The method for generalizing and setting uncertainty in the form of random variables for the corresponding event concentrations of COD and event concentrations of TN is specifically as follows:

[0058] When the minimum value, maximum value, and mean value of the event concentrations of COD and event concentrations of TN corresponding to all the rainwater volume Q T 、the initial rain runoff volume Q W and the initial rain runoff volume Q W can be obtained simultaneously, they are generalized in the form of a triangular distribution, and the formula is specifically as follows:

[0059]

[0060] When the mean value and standard deviation of the event concentrations of COD and event concentrations of TN corresponding to all the rainwater volume Q T 、the initial rain runoff volume Q W and the initial rain runoff volume Q W can be obtained simultaneously, they are generalized in the form of a normal distribution, and the formula is specifically as follows:

[0061]

[0062] When only the range information of the event concentrations of COD and event concentrations of TN corresponding to all the rainwater volume Q T 、the initial rain runoff volume Q W and the initial rain runoff volume Q W can be obtained, they are generalized in the form of a uniform distribution, and the formula is specifically as follows:

[0063]

[0064] Among them, TrD, N, and U represent triangular distribution, normal distribution, and uniform distribution respectively; f(x) represents the probability density function.

[0065] More preferably, in step 3, for the CH 4 carbon emission factor EF W_CH4 , the N 2 O carbon emission factor EF W_N2O caused by the discharge of the initial rainwater runoff into the receiving water body, the power consumption E d generated when the unit volume of rainwater is lifted by the rainwater pumping station, and the indirect carbon emission factor EF X generated during the operation and maintenance stage of the storage tank, the method of generalizing and setting uncertainties in the form of random variables is specifically as follows:

[0066] For the CH 4 carbon emission factor WF W_CH4 caused by the discharge of the initial rainwater runoff into the receiving water body, with a value of 0.048 kg CH 4 / kg COD, it is assumed that there is a 50% uncertainty in this parameter, and it is generalized in the form of a uniform distribution with the following formula:

[0067] EF W_CH4 -U(0.024, 0.072);

[0068] For the N 2 O carbon emission factor EF W_N2O caused by the discharge of the initial rainwater runoff into the receiving water body, with a value of 0.0005 kg N 2 O / kg N, it is assumed that there is a 50% uncertainty in this parameter, and it is generalized in the form of a uniform distribution with the following formula:

[0069] EF W_N2O -U(0.00025, 0.00075);

[0070] For the power consumption E d generated when the unit volume of rainwater is lifted by the rainwater pumping station, with a value of 0.03 kWh / m 3 , it is assumed that there is a 50% uncertainty in this parameter, and it is generalized in the form of a uniform distribution with the following formula:

[0071] E d -U(0.015, 0.045);

[0072] For the indirect carbon emission factor EF X generated during the operation and maintenance stage of the storage tank, with a value of 0.54 kgCO2 eq / (m 3 ·a), assuming a 30% uncertainty in this parameter and generalizing it in the form of a uniform distribution as follows:

[0073] EF X -U(0.378, 0.702).

[0074] More preferably, in step 4, based on all the rainwater volumes Q T 、the first flush runoff Q W 、the first flush runoff Q W corresponding to the event concentrations of COD, TN, and CH 4 carbon emission factor EF W_CH4 、N 2 O carbon emission factor EF W_N2O 、the power consumption E generated when lifting unit volume of rainwater by the rainwater pumping station d 、the indirect carbon emission factor EF generated during the operation and maintenance stage of the storage tank X random variable generalization settings, replacing them with random numbers, and then executing step 2 again to calculate the carbon emissions during the operation and maintenance period of the rainwater drainage system and the carbon emission capacity of the whole process, and recording the corresponding calculation results.

[0075] More preferably, in step 4, summarizing and reporting the simulation results means calculating the average value and standard deviation of the calculation results regarding the carbon emissions during the operation and maintenance period of the rainwater drainage system and the carbon emission capacity of the whole process, and forming a report on the carbon emissions during the operation and maintenance period of the rainwater drainage system and the carbon emission capacity of the whole process.

[0076] Advantages of the present invention:

[0077] The application of the present invention can make the accounting of carbon emissions during the operation and maintenance period of the rainwater drainage system and the carbon emission capacity of the whole process more objective, comprehensive, and reliable.

[0078] The present invention takes into account the direct carbon emissions generated after the first flush runoff carrying a large amount of pollutants enters the receiving water body, making the accounting of carbon emissions during the operation and maintenance period of the rainwater drainage system and the carbon emission capacity of the whole process more objective and comprehensive.

[0079] The method of the present invention takes into account the accounting differences of different rainwater drainage modes and provides carbon emission capacity indicators for the integrated whole process that are convenient for accounting, such as CE ZP 、CE TX and CE QP .

[0080] The present invention generalizes and sets uncertainties for parameters, such as rainfall volume, carbon emission factors, etc., in the form of generalized random variables, making full use of the statistical information involved in the statistics, while also comprehensively considering the inherent uncertainty of the statistical information, thereby further improving the reliability of the calculation of carbon emissions during the operation and maintenance period of the rainwater drainage system and the emission capacity of the entire process.

[0081] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] Figure 1 A flow chart showing an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0083] Example

[0084] The catchment area is 66000m 2 Carbon emissions accounting during the operation and maintenance period of the rainwater drainage system in a certain area.

[0085] The accounting of carbon emissions during the operation and maintenance period of the rainwater drainage system refers to the construction of carbon emission capacity accounting formulas for different emission units, including the direct carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, the indirect carbon emission capacity generated when all rainwater is lifted by the rainwater pumping station, and the indirect carbon emission capacity generated during the operation and maintenance stage of the storage tank; finally, based on the carbon emission capacity accounting formulas for different emission units, the carbon emissions during the operation and maintenance period of the rainwater drainage system under different rainwater drainage modes and the carbon emission capacity of the entire process are constructed.

[0086] The above area includes 1 rainwater storage tank and 1 rainwater lifting pump station, and the calculation time scale is 1 year. Figure 1 The process shown includes the following steps:

[0087] The calculation method of carbon emissions during the operation and maintenance period of the rainwater drainage system includes the following steps:

[0088] Step 1: Obtain basic data;

[0089] The basic data include the total rainfall, initial rainfall runoff, its COD and TN event concentrations, and the volume of the storage tank: the minimum value of the total rainfall QT (39600m 3 )、Maximum value(118800m 3 ) and mean (72600m 3 ), initial rain runoff Q W The minimum value (2970m 3 )、Maximum value(12474m 3 ) and mean (6171m3 )), the mean of the event concentrations of COD and TN corresponding to the initial rain runoff (0.0951 kg COD / m 3 and 0.0223 kg N / m 3 ), and the standard deviation (0.0173 kg COD / m 3 and 0.0041 kg N / m 3 ), as well as the volume of 1 existing rainwater storage tank (V X = 580 m 3 ).

[0090] In step 1, obtain the statistics of the total rainwater volume, initial rain runoff, and their event concentrations of COD and TN, and it should also include the minimum value, maximum value, mean value, and standard deviation of these statistics. This is because for the total rainwater volume and initial rain runoff, these statistics are the sum of the statistical values of many rainfall events throughout the year, and a single statistic itself has non-precision and contingency due to limited measurement means and other reasons, that is, it has a certain range rather than a fixed value, which leads to a certain degree of uncertainty in the total rainwater volume, initial rain runoff, etc. For the event concentrations of COD and TN throughout the year, they are based on the levels of many single statistical values throughout the year, and similarly have a certain degree of uncertainty. For the uncertainty of the statistics, the classic mathematical expressions are the minimum value, maximum value, mean value, standard deviation, etc. of the statistics.

[0091] Step 2: Construct accounting formulas for the carbon emissions during the operation period and the total process emission capacity of the rainwater drainage system according to different rainwater drainage modes;

[0092] Step 3: Generalize the parameters in the accounting formula and set their uncertainties;

[0093] Step 4: Simulate the carbon emissions during the operation period and the total process emission capacity of the rainwater drainage system based on the uncertainty of the parameters, and summarize and report the simulation results.

[0094] In practical applications, the rainwater drainage modes include self-drainage mode, storage mode, and forced drainage mode. The principle of constructing the accounting formulas for the carbon emissions during the operation period and the total process emission capacity of the rainwater drainage system is as follows:

[0095] First, construct the accounting formulas for the carbon emission capacity of different emission units.

[0096] The first part is the direct carbon emission capacity caused by the discharge of the initial rain runoff into the receiving water body:

[0097] CE W_CH4 = COD r ·EF W_CH4 ·28

[0098]

[0099] In the formula, CE W_CH4 , CE W_N2O and CE W are respectively the CH 4 carbon emission capacity, N 2 O carbon emission capacity and direct carbon emission capacity caused by the discharge of the initial rainwater runoff into the receiving water body, and the unit of all of them is kg CO 2 eq / m 3 ; COD r and TN r are respectively the event concentrations of COD and TN corresponding to the initial rainwater runoff, and the units are kg COD / m 3 and kg N / m 3 ; EF W_CH4 and EF W_N2O are respectively the CH 4 carbon emission factor and N 2 O carbon emission factor caused by the discharge of the initial rainwater runoff into the receiving water body, and the units are kgCH 4 / kg COD and kg N 2 O / kg N; 28 and 265 are respectively the global warming potential values of CH 4 and N 2 O, and the units are kgCO 2 eq / kg CH 4 and kg CO 2 eq / kg N 2 O; 22 / 14 is the molecular mass ratio of 1 / 2N 2 O to N; Q W and Q T are respectively the volume of the initial rain runoff and the volume of all rainwater, and the unit of both is m 3 .

[0100] The second part is the indirect carbon emission capacity generated when all rainwater is lifted by the rain pump station:

[0101] CE E = E d ·EF d

[0102] In the formula, CE E is the indirect carbon emission capacity generated when all rainwater is lifted by the rain pump station, and the unit is kgCO 2 eq / m 3 ; E d is the power consumption generated when the rainwater of unit volume is lifted by the rain pump station, and the unit is kWh / m 3 ; EF d is the regional power grid emission factor, and the unit is kg CO2 eq / kWh.

[0103] The third part is the indirect carbon emission capacity generated during the operation and maintenance stage of the storage pool:

[0104]

[0105] In the formula, CE X is the indirect carbon emission capacity generated during the operation and maintenance stage of the storage pool, with the unit of kg CO 2 eq / m 3 ; V X is the volume of the storage pool, with the unit of m 3 ; EF X is the indirect carbon emission factor generated during the operation and maintenance stage of the storage pool, with the unit of kgCO 2 eq / (m 3 ·a); T is the duration of the accounting time scale.

[0106] For the self-discharge mode, that is, rainwater is directly discharged into the receiving water body by its own gravity. At this time, only the direct carbon emissions generated in the first part exist. The specific calculation formulas for carbon emissions during the operation and maintenance period and the carbon emission capacity throughout the process in the self-discharge mode are as follows:

[0107] TCE ZP = CE W ·Q T

[0108]

[0109] In the formula, TCE ZP is the carbon emissions during the operation and maintenance period in the self-discharge mode, with the unit of kg CO 2 eq; CE ZP is the carbon emission capacity throughout the process in the self-discharge mode, with the unit of kg CO 2 eq / m 3 .

[0110] For the storage mode, that is, rainwater first passes through the rainwater storage pool and then is lifted to the sewage treatment plant by the rainwater pumping station without being directly discharged into the receiving water body. At this time, indirect carbon emissions generated in the second part and the third part exist simultaneously, but direct carbon emissions generated in the first part do not exist. The specific calculation formulas for carbon emissions during the operation and maintenance period and the carbon emission capacity throughout the process in the storage mode are as follows:

[0111] TCE TX = (CE E + CE X )·Q T

[0112]

[0113] Wherein, TCE TX is the carbon emission during the operation and maintenance period of the storage mode, with the unit of kg CO 2 eq; CE TX is the carbon emission capacity throughout the whole process of the storage mode, with the unit of kg CO 2 eq / m 3 .

[0114] For the strong drainage mode, that is, the rainwater first passes through the rainwater storage tank, and then is lifted by the rainwater pumping station and directly discharged into the receiving water body. At this time, there are both the direct carbon emissions generated in the first part and the indirect carbon emissions generated in the second and third parts. The specific calculation formulas for the carbon emissions during the operation and maintenance period and the carbon emission capacity throughout the whole process in the strong drainage mode are as follows:

[0115] TCE QP =(CE W +CE E +CE X )·Q T

[0116]

[0117] Wherein, TCE QP is the carbon emission during the operation and maintenance period of the strong drainage mode, with the unit of kg CO 2 eq; CE QP is the carbon emission capacity throughout the whole process of the strong drainage mode, with the unit of kg CO 2 eq / m 3 .

[0118] In some embodiments, in step 3, for all the rainfall volumes Q T , the initial rain runoff Q W , the initial rain runoff Q W , the event concentrations of COD, TN corresponding to them, the CH 4 carbon emission factor EF W_CH4 caused by the discharge of the initial rain runoff into the receiving water body, the N 2 O carbon emission factor EF W_N2O , the power consumption E d generated when the rainwater is lifted by the rainwater pumping station per unit volume, and the indirect carbon emission factor EF X generated during the operation and maintenance stage of the storage tank are generalized and set with uncertainty in the form of random variables.

[0119] In some embodiments, in step 3, for all the rainfall volumes Q T , the initial rain runoff Q W , the initial rain runoff Q WThe method for generalizing and setting the uncertainty of the event concentrations of COD and TN corresponding thereto in the form of random variables is specifically as follows:

[0120] When the total rainfall volume Q T 、the initial rain runoff volume Q W and the initial rain runoff volume Q W corresponding thereto can be obtained simultaneously, and the minimum, maximum and mean values of the event concentrations of COD and TN corresponding thereto are generalized in the form of a triangular distribution. The specific formula is as follows:

[0121]

[0122] When the total rainfall volume Q T 、the initial rain runoff volume Q W and the initial rain runoff volume Q W corresponding thereto can be obtained simultaneously, and the mean value and standard deviation of the event concentrations of COD and TN corresponding thereto are generalized in the form of a normal distribution. The specific formula is as follows:

[0123]

[0124] When only the range information of the event concentrations of COD and TN corresponding to the total rainfall volume Q T 、the initial rain runoff volume Q W and the initial rain runoff volume Q W corresponding thereto can be obtained, it is generalized in the form of a uniform distribution. The specific formula is as follows:

[0125]

[0126] Among them, TrD, N, and U represent triangular distribution, normal distribution and uniform distribution respectively; f(x) represents the probability density function.

[0127] In some embodiments, in step 3, for the CH 4 carbon emission factor EF W_CH4 caused by the discharge of the initial rain runoff into the receiving water body, the N 2 O carbon emission factor EF W_N2O caused by the discharge of the initial rain runoff into the receiving water body, the power consumption E d generated when the rainwater per unit volume is lifted by the rainwater pumping station, and the indirect carbon emission factor EF X generated during the operation and maintenance stage of the storage tank, the method for generalizing and setting the uncertainty in the form of random variables is specifically as follows:

[0128] Generalize and set the uncertainty of the parameters in the accounting formula.

[0129] According to the specific situation of the data obtained above, the total rainfall volume Q at the accounting time scaleT , the initial rain runoff Q W is generalized as a triangular distribution variable:

[0130] Q T ~TrD(39600, 118800, 72600), Q W ~TrD(2970, 12474, 6171);

[0131] The event concentrations of COD and TN corresponding to the initial rain runoff Q W are generalized as normal distribution variables:

[0132] COD r ~N(0.0951, 0.0173 2 ), TN r -(0.0223, 0.0041 2 );

[0133] For the CH 4 carbon emission factor EF W_CH4 caused by the discharge of the initial rain runoff into the receiving water body, it is assumed that there is a 50% uncertainty in this parameter and it is generalized in the following uniform distribution form:

[0134] EF W_CH4 -U(0.024, 0.072);

[0135] For the N 2 O carbon emission factor EF W_N2O caused by the discharge of the initial rain runoff into the receiving water body, it is assumed that there is a 50% uncertainty in this parameter and it is generalized in the following uniform distribution form:

[0136] EF W_N2O -U(0.00025, 0.00075);

[0137] For the electricity consumption E d generated when pumping a unit volume of rainwater through a rainwater pumping station, it is assumed that there is a 50% uncertainty in this parameter and it is generalized in the following uniform distribution form:

[0138] E d -U(0.015, 0.045);

[0139] For the indirect carbon emission factor EF X generated during the operation and maintenance stage of the storage tank, it is assumed that there is a 30% uncertainty in this parameter and it is generalized in the following uniform distribution form:

[0140] EF X -U(0.378, 0.702).

[0141] Step 4: Simulate the carbon emissions during the operation and maintenance period and the full-process emission capacity of the rainwater drainage system based on parameter uncertainty, and summarize and report the simulation results.

[0142] Using MATLAB software, based on the generalization settings of the random variables of the parameters in Step 3, for all the rainwater volumes Q T , the initial rainwater runoff volume Q W , the initial rainwater runoff volume Q W corresponding event concentrations of COD, event concentrations of TN, CH 4 carbon emission factor EF W_CH4 caused by the discharge of the initial rainwater runoff into the receiving water body, N 2 O carbon emission factor EF W_N2O , the power consumption E generated when lifting unit volume of rainwater through the rainwater pumping station d , the indirect carbon emission factor EF generated during the operation and maintenance stage of the storage tank X and other parameters are replaced with random numbers, and it is set that each variable generates 50,000 random numbers. Substitute them into the formula in Step 2 to calculate the carbon emissions during the operation and maintenance period and the full-process emission capacity of the rainwater drainage system under different rainwater drainage modes in this area, and record the corresponding calculation results.

[0143] Summarize and report the above calculation and simulation results, that is, calculate the mean and standard deviation of the carbon emissions during the operation and maintenance period and the full-process emission capacity of the rainwater drainage system under different rainwater drainage modes in this area, as shown in Table 1 below. The calculation results show that the carbon emissions during the operation and maintenance period of the rainwater drainage system in the self-discharge mode and its full-process emission capacity are the smallest compared with other modes, but its environmental and water conservancy risks are relatively large in actual projects (that is, it is prone to cause urban waterlogging disasters); the carbon emissions during the operation and maintenance period of the rainwater drainage system in the forced-discharge mode and its full-process emission capacity are the largest compared with other modes, but its system safety is relatively high, and it can timely discharge the accumulated rainwater in the city into the river to avoid urban waterlogging. Compared with the above two emission modes, the carbon emissions during the operation and maintenance period of the rainwater drainage system in the storage mode and its full-process emission capacity are moderate, and its system safety is also good, and it is not easy to cause urban waterlogging, which is a rainwater drainage mode worthy of promotion.

[0144] The simulation calculation results of the carbon emissions during the operation and maintenance period and the full-process emission capacity of the rainwater drainage system under different rainwater drainage modes are shown in the following table:

[0145] <![CDATA[kg CO 2 eq]]> Mean Standard Deviation Coefficient of Variation Maximum Value Minimum Value <![CDATA[TCE ZP > 955.4 421.6 44.1％ 3145.0 149.0 <![CDATA[TCE TX > 2139.1 664.9 31.1％ 4502.0 761.0 <![CDATA[TCE QP > 3094.5 786.2 25.4％ 6775.0 1138.9 <![CDATA[kg CO 2 eq / m 3 > Mean Standard Deviation Coefficient of Variation Maximum Value Minimum Value <![CDATA[CE ZP > 0.013 0.007 50.6％ 0.069 0.002 <![CDATA[CE TX > 0.028 0.007 24.9％ 0.045 0.014 <![CDATA[CE QP > 0.041 0.010 24.1％ 0.098 0.017

[0146] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art in this technical field based on the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art should fall within the protection scope determined by the claims.

Claims

1. A method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system; characterized in that: The steps include: Step 1: Obtain basic data; Step 2: Construct a calculation formula for carbon emissions during the operation and maintenance period of the rainwater drainage system and the emission capacity of the entire process according to different rainwater drainage modes; Step 3, generalizing and setting uncertainties for the parameters in the calculation formula; Step 4: Simulate the carbon emissions during the operation and maintenance period of the rainwater drainage system and the emission capacity of the entire process based on the uncertainty of the parameters, and summarize and report the simulation results.

2. The method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system according to claim 1 is characterized in that: In step 1, the basic data includes the volume V of the existing rainwater storage tank z , total rainfall amount Q T Its minimum, maximum and mean values, initial rain runoff Q W and its minimum, maximum and mean, as well as the initial rain runoff Q W The corresponding mean and standard deviation of the event concentration of COD and the event concentration of TN.

3. The method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system according to claim 2 is characterized in that: In step 2, when the rainwater drainage mode is the self-drainage mode, that is, the rainwater is directly discharged to the receiving water body by its own gravity, the specific calculation formula for the corresponding operation and maintenance period carbon emissions and the whole process carbon emission capacity is: TCE ZP =CE W ·Q T ; Where, TCE ZP Carbon emissions during the operation and maintenance period of the self-drainage mode, unit: kgCO2eq; CE ZP The carbon emission capacity of the whole process of the self-exhaust mode, unit: kgCO2eq / m 3 ; CE W It is the direct carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, in kg CO2eq / m 3 , the calculation formula is as follows: Among them, CE W_CH4 is the CH4 carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, in kgCO2eq / m 3 , the calculation formula is as follows: WHAT W_CH4 =COD r ·EF W_CH4 ·28; Among them, COD r is the event concentration of COD corresponding to the initial rainwater runoff, unit: kg COD / m 3 EF W_CH4 is the carbon emission factor of CH4 caused by the initial rainwater runoff discharged into the receiving water body, in kg CH4 / kg COD; 28 is the global warming potential of CH4, in kg CO2eq / kg CH4; CE W_N2O It is the N2O carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, in kg CO2eq / m 3 , the calculation formula is as follows: Among them, TN r The event concentration of TN corresponding to the initial rainwater runoff, in kg COD / m 3 and kg N / m 3 EF W_N2O is the carbon emission factor of N2O caused by the discharge of initial rainwater runoff into the receiving water body, in kg kg N2O / kg N; 265 is the global warming potential of N2O, in kg CO2eq / kg N2O; The molecular mass ratio of N2O to N is 1 / 2.

4. The method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system according to claim 2 is characterized in that: In step 2, when the rainwater drainage mode is the storage mode, that is, the rainwater first passes through the rainwater storage tank, and then relies on the rainwater pumping station to lift it to the sewage treatment plant instead of being directly discharged into the receiving water body, the corresponding operation and maintenance period carbon emissions and the specific calculation formula of the whole process carbon emission capacity are: TEC TX =(CE E +CE X )·Q T ; Where, TCE TX is the carbon emission during the operation and maintenance period of the regulation and storage mode, in kg CO2eq; CE TX is the carbon emission capacity of the whole process of the regulation and storage mode, in kg CO2eq / m 3 ; CE E It is the indirect carbon emission capacity generated when all rainwater is lifted by the rainwater pumping station, in kg CO2eq / m 3 , the calculation formula is as follows: WHAT E =E d ·EF d ; Among them, E d It is the power consumption generated when the unit volume of rainwater is lifted by the rainwater pumping station, in kWh / m 3 EF d is the regional grid emission factor, in kg CO2eq / kWh; CE X The indirect carbon emission capacity generated during the operation and maintenance phase of the storage pond, in kg CO2eq / m 3 , the calculation formula is as follows: Where V X is the volume of the storage tank, in m 3 EF X is the indirect carbon emission factor generated during the operation and maintenance phase of the storage pond, in kg CO2eq / (m 3 a); T is the length of the calculated time scale.

5. The method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system according to claim 2 is characterized in that: In step 2, when the rainwater drainage mode is the forced drainage mode, that is, the rainwater first passes through the rainwater storage tank, and then relies on the rainwater pumping station to lift and directly discharge it to the receiving water body, the corresponding operation and maintenance period carbon emissions and the specific calculation formula of the whole process carbon emission capacity are: TEC QP =(CE W +CE E +CE X )·Q T ; Where, TCE QP is the carbon emission during the operation and maintenance period of the strong exhaust mode, in kg CO2eq; CE QP The carbon emission capacity of the whole process of the strong exhaust mode, in kg CO2eq / m 3 ; CE W It is the direct carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, in kg CO2eq / m 3 , the calculation formula is as follows: Among them, CE W_CH4 is the CH4 carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, in kgCO2eq / m 3 , the calculation formula is as follows: WHAT W_CH4 =COD r ·EF W_CH4 ·28; Among them, COD r is the event concentration of COD corresponding to the initial rainwater runoff, unit: kg COD / m 3 EF W_CH4 is the carbon emission factor of CH4 caused by the initial rainwater runoff discharged into the receiving water body, in kg CH4 / kg COD; 28 is the global warming potential of CH4, in kg CO2eq / kg CH4; CE W_N2O is the N2O carbon emission capacity caused by the initial rainwater runoff discharged into the receiving water body, in units of kg CO2eq / m 3 , the calculation formula is as follows: Among them, TN r The event concentration of TN corresponding to the initial rainwater runoff, in kg COD / m 3 and kg N / m 3 EF W_N2O is the carbon emission factor of N2O caused by the discharge of initial rainwater runoff into the receiving water body, in kg kg N2O / kg N; 265 is the global warming potential of N2O, in kg CO2eq / kg N2O; The molecular mass ratio of N2O to N is 1 / 2; CE E It is the indirect carbon emission capacity generated when all rainwater is lifted by the rainwater pumping station, in kg CO2eq / m 3 , the calculation formula is as follows: WHAT E =E d ·EF d ; Among them, E d It is the power consumption generated when the unit volume of rainwater is lifted by the rainwater pumping station, in kWh / m 3 EF d is the regional grid emission factor, in kg CO2eq / kWh; CE X The indirect carbon emission capacity generated during the operation and maintenance phase of the storage pond, in kg CO2eq / m 3 , the calculation formula is as follows: Where V X is the volume of the storage tank, in m 3 EF X is the indirect carbon emission factor generated during the operation and maintenance phase of the storage pond, in kg CO2eq / (m 3 a); T is the length of the calculated time scale.

6. The method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system according to claim 2 is characterized in that: In step 3, the total rainfall amount Q under the calculated time scale is T , the initial rain runoff Q W , the initial rain runoff Q W The corresponding COD event concentration, TN event concentration, and CH4 carbon emission factor EF caused by the initial rainwater runoff discharged into the receiving water body W_CH4 , N2O carbon emission factor EF caused by initial rainwater runoff discharged into receiving water bodies W_N2O , the power consumption E generated when a unit volume of rainwater is lifted by the rainwater pumping station d , indirect carbon emission factor EF generated during the operation and maintenance phase of the storage pond X Generalization and uncertainty setting are performed in the form of random variables.

7. The method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system according to claim 6 is characterized in that: In step 3, the total rainfall amount Q T , the initial rain runoff Q W , the initial rain runoff Q W The corresponding event concentrations of COD and TN are generalized and set in uncertainty in the form of random variables as follows: When all the rainfall amounts Q can be obtained at the same time T , the initial rain runoff Q W and the initial rain runoff Q W The corresponding minimum, maximum and mean values ​​of the event concentration of COD and the event concentration of TN are generalized in the form of triangular distribution. The specific formula is as follows: O T ,Q W , COD r ,TN r ~TrD(minimum, maximum, mean): When all the rainfall amounts Q can be obtained at the same time T , the initial rain runoff Q W and the initial rain runoff Q W The corresponding event concentration of COD and the mean and standard deviation of the event concentration of TN are generalized in the form of normal distribution. The specific formula is as follows: When only the total rainfall amount Q can be obtained T , the initial rain runoff Q W and the initial rain runoff Q W The corresponding range information of COD event concentration and TN event concentration is generalized in the form of uniform distribution. The specific formula is as follows: Q T ,Q W ,COD r ,TN r ~U(minimum, maximum): Among them, TrD, N, and U represent triangular distribution, normal distribution, and uniform distribution respectively; f(x) represents the probability density function.

8. The method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system according to claim 6 is characterized in that: In step 3, the CH4 carbon emission factor EF resulting from the discharge of the initial rainwater runoff into the receiving water body is calculated. W_CH4 , the N2O carbon emission factor EF caused by the initial rainwater runoff discharged into the receiving water body W_N2O , the power consumption E generated when the unit volume of rainwater is lifted by the rainwater pumping station d , the indirect carbon emission factor EF generated during the operation and maintenance phase of the storage pond X The specific method of generalization and uncertainty setting in the form of random variables is: The CH4 carbon emission factor EF caused by the initial rainwater runoff discharged into the receiving water body W_CH4 , taking the value as 0.048kgCH4 / kg COD, assuming that this parameter has 50% uncertainty, and generalizing it in the form of uniform distribution as follows: EF W_CH4 -U(0.024,0.072); The N2O carbon emission factor EF caused by the initial rainwater runoff discharged into the receiving water body W_N2O , with a value of 0.0005 kgN2O / kg N, assuming a 50% uncertainty in this parameter, and generalizing it in the form of uniform distribution as follows: EF W_N2O -U(0.00025,0.00075); The power consumption E generated when the unit volume of rainwater is lifted by the rainwater pumping station d , the value is 0.03kWh / m 3 , assuming that the parameter has a 50% uncertainty, and generalizes it in the form of uniform distribution as follows: And d -U(0.015,0.045); For the indirect carbon emission factor EF generated during the operation and maintenance phase of the storage pond X , the value is 0.54kg CO2eq / (m 3 a), assuming that the parameter has a 30% uncertainty and generalizing it in the form of uniform distribution as follows: EF x -U(0.378,0.702)。 9. The method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system according to claim 6 is characterized in that: In step 4, based on the total rainfall amount Q under the calculated time scale T , the initial rain runoff Q W , the initial rain runoff Q W The corresponding COD event concentration, TN event concentration, and CH4 carbon emission factor EF caused by the initial rainwater runoff discharged into the receiving water body W_CH4 , N2O carbon emission factor EF caused by initial rainwater runoff discharged into receiving water bodies W_N2O , the power consumption E generated when a unit volume of rainwater is lifted by the rainwater pumping station d , indirect carbon emission factor EF generated during the operation and maintenance phase of the storage pond X The random variable generalization setting is replaced by random numbers, and then step 2 is executed again to calculate the carbon emissions during the operation and maintenance period of the rainwater drainage system and the emission capacity of the whole process, and the corresponding calculation results are recorded.

10. The method for calculating carbon emissions during the operation and maintenance period of a rainwater drainage system according to claim 9 is characterized in that: In step 4, summarizing and reporting the simulation results means calculating the mean and standard deviation of the calculated results on the carbon emissions during the operation and maintenance period of the rainwater drainage system and the emission capacity of the whole process, and forming a report on the calculated carbon emissions during the operation and maintenance period of the rainwater drainage system and the emission capacity of the whole process.

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