A calculation method for gas pipeline intake configuration in waste gas treatment

Abstract

The present invention provides a method for calculating the configuration of the intake volume of a natural gas pipeline in waste gas treatment, including: 1) constructing an online monitoring concentration prediction model using a modeled coating operation plan; 2) constructing a verification correction model using a modeled coating operation plan and a standard reference concentration; 3) obtaining the current coating operation plan, and obtaining a prediction curve of the online monitoring concentration through the online monitoring concentration prediction model; 4) verifying the prediction curve of the online monitoring concentration through the verification correction model to obtain an accurate concentration prediction curve; 5) calculating the natural gas consumption based on the accurate concentration prediction curve and according to the natural gas consumption calculation rule. The method of the present invention has high calculation accuracy, is simple and easy to implement, can effectively and accurately predict the VOCs concentration change curve at the main pipe inlet, and dynamically configures the natural gas intake according to the mechanism model of the equipment operation, so as to achieve the purpose of reducing the amount of natural gas required for the equipment operation.

Description

Technical Field

[0001] The invention relates to a method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment, and belongs to the technical field of energy-saving control of organic waste gas treatment. Background Art

[0002] Chemical, pharmaceutical, shipbuilding and other industrial enterprises will produce volatile organic waste gas (VOCs) during the production process. The treatment of organic waste gas is an important part of environmental protection work. The current mainstream treatment method of organic waste gas is a combination of zeolite rotor thermal desorption and regenerative thermal oxidizer (RTO): after the waste gas is collected and pre-treated, it is sent to the zeolite molecular sieve rotor system for thermal desorption. During the thermal desorption process, large air volume and low concentration organic waste gas is concentrated into small air volume and high concentration waste gas. The concentrated waste gas enters the regenerative thermal oxidizer for combustion purification, and finally meets the emission standards.

[0003] For chemical and pharmaceutical enterprises, their production processes are often continuous. Therefore, the concentration of organic waste gas generated is usually stable, and the components of organic waste gas are usually certain. Therefore, the amount of natural gas used in the combustion process of the regenerative thermal oxidizer is also relatively stable. Therefore, the amount of natural gas intake required in the regenerative thermal oxidizer can be managed according to the detection value of the online concentration monitoring instrument at the main pipe inlet.

[0004] However, for ship companies, organic waste gas is mainly generated by coating operations, and the working mode of coating operations is intermittent. Therefore, the concentration and composition of organic waste gas generated under different working conditions of coating operations will vary greatly. If natural gas configuration is performed based on the detection value of the online monitoring concentration instrument at the entrance of the main pipe, there will be obvious defects: First, VOCs emission belongs to a large delay mechanism. If the VOC concentration detection instrument on the regenerative thermal oxidizer is used for concentration detection, and the natural gas intake volume is directly configured based on the concentration, then due to the principle of the delay mechanism, such management may lead to a certain stage. The high temperature conditions that the RTO combustion chamber needs to achieve to maintain the spontaneous combustion of VOCs cannot be met, making the RTO unable to work. This is also the reason why excessive natural gas is often used to assist combustion in order to maintain the high temperature of the combustion chamber in the actual operation of waste gas treatment in ship companies. Second, the concentration change of exhaust gas generated by the painting operation is not only related to its own emission characteristics, but also to factors such as operation time and material consumption. It is also affected by uncertain factors such as the non-fixed operation location, and is affected by the complex and harsh working environment, which makes the VOCs concentration monitoring data unstable and uncertain. There is a large amount of interference data. At present, the monitoring results of the VOC concentration detection instrument on the regenerative thermal oxidation furnace are often greater than the true value (the value obtained by direct sampling of VOCs gas for concentration analysis), which is not accurate. If the energy consumption management uses the detection data as the original basis, the natural gas intake configuration based on this will not be accurate due to the inaccurate original basis.

[0005] In view of the above situation, it is currently necessary to study a method that can scientifically and reasonably calculate the minimum natural gas intake volume to maintain spontaneous combustion of the regenerative thermal oxidizer equipment, so as to improve the current situation of high energy consumption of exhaust gas treatment in the above-mentioned shipping companies. Summary of the invention

[0006] The present invention is made to solve the above-mentioned problem, and aims to provide a method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment.

[0007] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0008] The present invention provides a method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment, which is characterized by comprising:

[0009] 1) Use modeling coating operation plan to build an online monitoring concentration prediction model;

[0010] 2) Construct a calibration correction model using the modeled coating operation plan and standard reference concentration;

[0011] 3) obtaining the current coating operation plan, and obtaining a prediction curve of the online monitoring concentration through the online monitoring concentration prediction model;

[0012] 4) Verifying the prediction curve of the online monitoring concentration by the verification correction model to obtain an accurate concentration prediction curve;

[0013] 5) Based on the accurate concentration prediction curve and the natural gas consumption calculation rules, calculate the natural gas consumption.

[0014] Furthermore, in the calculation method of the gas intake configuration of the natural gas pipeline in the waste gas treatment provided by the present invention, there may also be such a feature: wherein, the specific process of step 1) constructing the online monitoring concentration prediction model is as follows:

[0015] S1-1: Record the modeling and painting work plan:

[0016] The coating operation plan S consists of N sections of working conditions S i Composition, i=1, ..., N, the recorded modeling coating operation plan data includes the number of sections, the working condition data of each section, and the online monitoring concentration curve of the coating operation plan;

[0017] S1-2: Correlate the working condition data of each working condition with each band in the online monitoring concentration curve of the coating operation plan;

[0018] S1-3: Perform curve fitting for the online monitoring concentration of each working condition:

[0019] ① Any i-th working condition S i The online monitoring concentration is fitted using the logarithmic Gaussian function of formula (1):

[0020]

[0021] In formula (1), t represents the working condition S i A moment in time; represents the online monitoring concentration at time t; e represents the natural logarithm; t i Indicates the working condition S i The time difference between the start time of the current painting operation and the planned start time of the current painting operation; ln(*) represents the natural logarithmic function; K i , μ i , σ i 2 is the characteristic parameter of the logarithmic Gaussian function, calculated from the Gaussian curve;

[0022] ② Define the entire coating operation plan S Online monitoring concentration can be through N working conditions S i The concentrations of are superimposed and expressed as:

[0023]

[0024] In formula (2), It represents the online monitoring concentration of the coating operation plan S;

[0025] S1-4: Constructing online monitoring concentration prediction model:

[0026] From formula (1), we can get S for each working condition: i A Gaussian curve will be fitted, thus obtaining a set of characteristic parameters K i , μ i , σ i 2 , then the N working conditions of the entire coating operation plan S obtain the characteristic parameter set {K i , μ i , σ i 2}, i=1,...,N;

[0027] Construct a set of conditions {S i}, i = 1, ..., each working condition and characteristic parameter set in N {K i , μ i , σ i 2}, i=1,..., the mapping relationship g of each set of characteristic parameters in N is expressed as follows:

[0028]

[0029] According to formula (2), the following online monitoring concentration prediction model for coating operation plan is constructed:

[0030]

[0031] In formula (4), It represents the prediction result of the online monitoring concentration of the current coating operation plan; the current coating operation plan is divided into M working conditions S i , i=1,...,M; Indicates the working condition S in the current coating operation plan i The predicted result of the online monitoring concentration is based on the working condition S in the current coating operation plan. i A Gaussian curve drawn based on a set of characteristic parameters of a logarithmic Gaussian function obtained according to formula (3).

[0032] Furthermore, in the calculation method for the configuration of the natural gas pipeline intake volume in the exhaust gas treatment provided by the present invention, it can also have the following characteristics: wherein, the mapping relationship g between the operating condition and the characteristic parameter in step S1-4 is constructed using the XGBoost model.

[0033] Furthermore, in the method for calculating the gas intake configuration of the natural gas pipeline in the waste gas treatment provided by the present invention, there may also be such a feature: wherein, the specific process of constructing the verification correction model in step 2) is as follows:

[0034] The standard reference concentration refers to the monitoring concentration obtained by the third-party monitoring agency through exhaust gas sampling and analysis at the inlet of the exhaust main pipe while obtaining the online monitoring concentration of the modeling coating operation plan;

[0035] The calibration correction model is established by constructing the mapping relationship h between the online monitoring concentration of the modeled coating operation plan and the standard reference concentration, which is expressed as follows:

[0036]

[0037] In formula (5), C O Indicates online monitoring concentration; C L Indicates standard reference concentration.

[0038] Furthermore, in the calculation method for the configuration of the natural gas pipeline intake volume in the waste gas treatment provided by the present invention, it can also have the following characteristics: wherein, the mapping relationship h between the online monitoring concentration of the modeled coating operation plan and the standard reference concentration is constructed using the GPR model.

[0039] Furthermore, in the calculation method for the configuration of the natural gas pipeline intake volume in the exhaust gas treatment provided by the present invention, it can also have the following characteristics: wherein, step 4) is specifically: taking the predicted value of the online monitoring concentration of the current coating operation plan as an input item, and using the mapping relationship h of the verification correction model to output the corresponding standard reference concentration, the concentration curve represented by the output standard reference concentration is the accurate concentration prediction curve.

[0040] Furthermore, in the method for calculating the gas intake configuration of the natural gas pipeline in the waste gas treatment provided by the present invention, there may also be such a feature: wherein the specific process of step 5) is as follows;

[0041] S5-1: Divide the painting stage and curing stage according to the accurate concentration prediction curve;

[0042] S5-2: Calculate the air volume of the main engine:

[0043]

[0044] In formula (6), L1 represents the design value of the main fan air volume; Indicates the main fan air volume during actual operation;

[0045] S5-3: Calculate the air volume range of the desorption fan:

[0046]

[0047] In formula (7), ρ U and ρ L is the design parameter of the equipment;

[0048] S5-4: Concentration ratio The upper and lower limits of the concentration ratio are calculated based on the ratio of the main fan air volume to the desorption fan air volume.

[0049]

[0050] S5-5: Calculate the concentration C on the accurate concentration prediction curve L Critical point C that does not require natural gas combustion T :

[0051]

[0052] In formula (9), It is the concentration of VOCs that the RTO equipment maintains for spontaneous combustion;

[0053] S5-6: Calculate the natural gas consumption F:

[0054] When C L >C T When C L ≤C T When , the natural gas consumption is the same as that under the condition without optimization;

[0055] S5-7: According to the critical point C T Calculate the gas supply stop time T Start and gas supply start time T End ;

[0056] S5-8: Calculate the actual concentration ratio R during the operation of the RTO equipment True :

[0057]

[0058] In formula (10), F refers to the amount of natural gas used.

[0059] Furthermore, in the calculation method for the configuration of the intake volume of the natural gas pipeline in the waste gas treatment provided by the present invention, it can also have the following characteristics: wherein, the division rule of step S5-1 is as follows: the 1 / 2 time point where the extreme value of the last peak of the accurate concentration prediction curve occurs is taken as the dividing line, the time period before this is the painting stage, and the time period after this is the curing stage.

[0060] Furthermore, in the method for calculating the gas intake configuration of the natural gas pipeline in the waste gas treatment provided by the present invention, there may also be such a feature: wherein the gas supply stop time point T in step S5-5 is Start and gas supply start time T End The calculation is as follows: In the accurate concentration prediction curve with time as the horizontal axis and organic waste gas concentration as the vertical axis, draw the critical point C T , critical point C T is a straight line parallel to the horizontal axis, which forms an intersection with the accurate concentration prediction curve. The situation of the intersection is as follows: If the slope of the accurate concentration prediction curve at the intersection is positive, then the time point of the horizontal coordinate corresponding to the intersection is the gas supply stop time point T End ; If the slope of the accurate concentration prediction curve at the intersection is negative, then the time point on the abscissa corresponding to the intersection is the gas supply start time T Start .

[0061] Beneficial effects of the present invention:

[0062] In the calculation method of the natural gas pipeline intake configuration in the waste gas treatment of the present invention, by collecting the coating operation plan data as the modeling data, and entrusting the third-party testing agency to measure the value VOCs as the standard reference concentration while collecting the modeling data, the online monitoring concentration prediction model constructed by the modeling data can predict the online monitoring concentration curve, and the mapping relationship constructed by the modeling data and the standard reference concentration can be used to correct the online monitoring concentration curve, so as to obtain an accurate concentration prediction curve. The concentration prediction curve method in the present invention solves the problem of how to accurately predict the change of VOCs concentration under the interference of large delays and unstable factors. The subsequent natural gas intake configuration calculation of the present invention is based on the accurate concentration prediction curve, so the calculated result has a high accuracy. The natural gas intake configuration calculation is based on the concentration ratio and VOCs concentration coupling mechanism model to achieve the purpose of dynamically configuring natural gas, which can optimize the natural gas intake required for the operation of RTO equipment under any working condition, not limited to the high or low VOCs concentration. The scheme of the present invention provides strong technical support for the waste gas treatment of ship enterprises, and achieves the beneficial effects of energy saving, emission reduction and cost efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 It is a step flow of a method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment in an embodiment of the present invention;

[0064] Figure 2 It is the online monitoring concentration curve actually measured by the instrument at the main pipe inlet before optimization under a certain working condition in the embodiment of the present invention, the predicted online monitoring concentration curve, and the accurate concentration prediction curve after verification;

[0065] Figure 3It is the configuration of the natural gas intake volume before and after optimization of a certain working condition in an embodiment of the present invention. DETAILED DESCRIPTION

[0066] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the following embodiments are combined with the accompanying drawings to specifically illustrate the technical solutions of the present invention.

[0067] The present embodiment provides a method for calculating the gas pipeline intake configuration in waste gas treatment, which is used to calculate the minimum natural gas intake for maintaining spontaneous combustion of a regenerative thermal oxidizer equipment for organic waste gas treatment in a shipping enterprise, thereby operating according to the intake calculation result to achieve the effect of reducing the operating energy consumption of the regenerative thermal oxidizer.

[0068] The online monitoring concentration and online monitoring concentration curve mentioned in the following text refer to the VOCs concentration value and VOCs concentration curve (that is, the curve with time as the horizontal axis and VOCs concentration value as the vertical axis) monitored by the instrument installed at the inlet of the organic waste gas main pipe in the regenerative thermal oxidizer; the predicted value and predicted curve of the online monitoring concentration refer to the VOCs concentration value and VOCs concentration curve predicted by the online monitoring concentration prediction model.

[0069] See also Figure 1 The calculation method of the gas intake configuration of the natural gas pipeline in the waste gas treatment includes the following steps:

[0070] Step 1) Use the modeling coating operation plan to build an online monitoring concentration prediction model. The specific process is as follows:

[0071] S1-1: Collect and record modeling and painting work plan:

[0072] The coating operation plan S consists of N sections of working conditions S i Composition, i = 1, ..., N. The modeling coating operation plan data collected and recorded in this step is the relevant data obtained by collecting the actual operation of the regenerative thermal oxidation furnace before energy consumption optimization. The modeling coating operation plan data includes the number of sections, the working condition data of each section, and the online monitoring concentration curve of the coating operation plan. The number of sections and the working condition data of each section are recorded in a record table. The working condition data includes the start time of the operation Job end time Number of spray guns G i , Paint volume P i , Solvent dosage Q i , Spraying area A i .

[0073] S1-2: Associate the working condition data of each working condition with each band in the online monitoring concentration curve of the coating operation plan one by one:

[0074] Since the segmented working conditions in the coating operation plan S have the characteristic of high discreteness, the working time of the segmented working conditions in the working condition data recording table is too dispersed, and accordingly, the online monitoring concentration curve of the coating operation plan S is expressed as multiple bands. Based on this situation, this step associates the working condition data recorded in the working condition data recording table with each band in a one-to-one correspondence.

[0075] The above working condition data of different working conditions are based on their operation start time. and the end time of the job The specific division process is as follows:

[0076] ① Division of job start time. Define StartId as the start time sequence number of the segmented working condition job. If the job start time is within the specified interval, the StartId is equal; otherwise, they are sorted according to the start time sequence.

[0077] ② Division of operation end time. Define EndId as the end time sequence number of the segmented operation. If the end time of the segmented operation is within the specified interval, the EndId is equal; otherwise, proceed according to the end time sequence.

[0078] ③ Division by working condition. Define PartId as the serial number of the segmented working condition. If the segmented working conditions have different StartId and EndId, determine whether there are non-overlapping working times; if so, compare whether the end time of the two working times is within the specified interval; if within the specified interval, the PartId is equal.

[0079] ④ According to the results of the sub-condition division, define GroupId as the internal grouping of the sub-condition. If the sub-conditions have the same StartId and EndId, the GroupId is equal.

[0080] The data set of the working condition obtained by the division is expressed as follows:

[0081]

[0082] S1-3: Perform curve fitting for the online monitoring concentration of each working condition:

[0083] ① Any i-th working condition S i The online monitoring concentration is fitted using the logarithmic Gaussian function of formula (1):

[0084]

[0085] In formula (1), t represents the working condition S i A moment in time; represents the online monitoring concentration at time t; e represents the natural logarithm; t i Indicates the working condition S iThe time difference between the operation start time of the painting operation plan S and the operation start time of the current painting operation plan (the operation start time of the painting operation plan S is the operation start time of the first working condition, and the operation end time of the painting operation plan S is the operation end time of the last working condition); ln(*) represents the natural logarithm function; K i , μ i , σ i 2 is the characteristic parameter of the logarithmic Gaussian function, calculated from the Gaussian curve;

[0086] ② Define the entire coating operation plan S Online monitoring concentration can be through N working conditions S i The concentrations of are superimposed and expressed as:

[0087]

[0088] In formula (2), Represents the online monitoring concentration of the coating operation plan S.

[0089] S1-4: Construct an online monitoring concentration prediction model.

[0090] From formula (1), we can get S for each working condition: i A Gaussian curve will be fitted, thus obtaining a set of characteristic parameters K i , μ i , σ i 2 , then the N working conditions of the entire coating operation plan S obtain the characteristic parameter set {K i , μ i , σ i 2}, i=1,...,N;

[0091] Using XGBoost model to build working condition set {S i}, i = 1, ..., each working condition and characteristic parameter set in N {K i , μ i , σ i 2}, i=1,..., the mapping relationship g of each set of characteristic parameters in N is expressed as follows:

[0092]

[0093] According to formula (2), the following online monitoring concentration prediction model for coating operation plan is constructed:

[0094]

[0095] In formula (4), It represents the prediction result of the online monitoring concentration of the current coating operation plan; the current coating operation plan is divided into M working conditions S i , i=1,...,M; Indicates the working condition S in the current coating operation plan i The predicted result of the online monitoring concentration is based on the working condition S in the current coating operation plan. i A Gaussian curve drawn based on a set of characteristic parameters of a logarithmic Gaussian function obtained according to formula (3).

[0096] Step 2) Use the modeled coating operation plan and standard reference concentration to build a calibration correction model. The specific process is as follows:

[0097] The GPR model is used to construct the mapping relationship between the online monitoring concentration of the coating operation plan and the standard reference concentration to establish a calibration correction model, which is expressed as follows:

[0098]

[0099] In formula (5), C O Indicates online monitoring concentration; C L Indicates standard reference concentration.

[0100] The above standard reference concentration refers to the monitoring concentration obtained by the third-party monitoring agency entrusted to conduct exhaust gas sampling and analysis at the entrance of the exhaust main pipe while collecting and obtaining the online monitoring concentration of the modeling coating operation plan. The standard reference concentration measured by exhaust gas sampling is lower than the online monitoring concentration of instrument monitoring. This is the difference between the current status of instrument monitoring data and the standard reference concentration.

[0101] Step 3) Obtain the current coating operation plan, and obtain the prediction curve of the online monitoring concentration through the online monitoring concentration prediction model. The specific process is as follows:

[0102] First, the current coating operation plan is divided into sections according to the same sectioning rules in step 2). Then, the working condition data of each sub-condition is used as input items, and the characteristic parameters corresponding to each sub-condition are obtained through the mapping relationship g of formula (3). Then, a Gaussian curve is obtained through a set of characteristic parameters corresponding to each sub-condition. That is, the concentration prediction result (concentration prediction curve) of the sub-operating condition. Finally, the prediction curve of the online monitoring concentration of the entire current coating operation plan is obtained through the online monitoring concentration prediction model of formula (4).

[0103] Step 4) Verify the prediction curve of the online monitoring concentration by verifying the correction model to obtain an accurate concentration prediction curve. The specific process is as follows:

[0104] The predicted value of the online monitoring concentration of the current coating operation plan is taken as the input item, and the mapping relationship h of the correction model is verified by formula (4) to output the corresponding standard reference concentration. The concentration curve represented by the output standard reference concentration is the accurate concentration prediction curve.

[0105] Step 5) Based on the accurate concentration prediction curve and the natural gas usage calculation rules, calculate the natural gas usage. The specific process is as follows;

[0106] S5-1: Divide the painting stage and curing stage according to the accurate concentration prediction curve.

[0107] The specific division rules are as follows: the 1 / 2 time point of the extreme value of the last peak of the accurate concentration prediction curve is used as the dividing line. The time period before this is the painting stage, and the time period after this is the curing stage.

[0108] S5-2: Calculate the air volume of the main engine:

[0109]

[0110] In formula (6), L1 represents the design value of the main fan air volume; Indicates the main fan air volume during actual operation.

[0111] S5-3: Calculate the air volume range of the desorption fan:

[0112]

[0113] In formula (7), ρ U is the equipment design parameter of the main fan, ρ L These are the equipment design parameters of the desorption fan, and they are all known parameters.

[0114] S5-4: Concentration ratio The upper and lower limits of the concentration ratio are calculated based on the ratio of the main fan air volume to the desorption fan air volume.

[0115]

[0116] S5-5: Calculate the concentration C on the accurate concentration prediction curve L Critical point C that does not require natural gas combustion T :

[0117]

[0118] In formula (9), It is the VOCs concentration that the RTO equipment maintains for spontaneous combustion.

[0119] S5-6: Calculate the natural gas consumption F:

[0120] See also Figure 2 and Figure 3 , when C L >C T When C L ≤C T , the natural gas consumption is the same as that under the non-optimized working conditions.

[0121] S5-7: According to the critical point C T Calculate the gas supply stop time T Start and gas supply start time T End .

[0122] See also Figure 2 In the accurate concentration prediction curve with time as the horizontal axis and organic waste gas concentration as the vertical axis, draw the critical point C T , critical point C T is a straight line parallel to the horizontal axis. In this embodiment, the critical point C T The VOCs concentration is 200mg / m 3 The straight line and the accurate concentration prediction curve form an intersection, and the situation of the intersection is as follows: If the slope of the accurate concentration prediction curve at the intersection is positive, then the time point of the horizontal coordinate corresponding to the intersection is the gas supply stop time point T End , for example, in this embodiment Figure 2 T End , Figure 3 It indicates that the gas supply is stopped at this moment; if the slope of the accurate concentration prediction curve at the intersection is negative, the time point on the horizontal axis corresponding to the intersection is the gas supply start time point T Start , for example, in this embodiment Figure 2 T Start , Figure 3 This indicates that gas supply starts at this moment.

[0123] S5-8: Calculate the actual concentration ratio R during the operation of the RTO equipment True :

[0124]

[0125] In formula (10), F refers to the amount of natural gas used.

[0126] It can be seen from the above embodiments that the calculation method for the configuration of the natural gas pipeline intake volume in the waste gas treatment of the present invention can effectively and accurately predict the VOCs concentration change curve at the main pipe inlet, and can calculate the natural gas intake volume and concentration ratio according to the mechanism model of the equipment operation, thereby realizing scientific and reasonable dynamic configuration of natural gas. Figure 3 , Figure 3The shaded portion in the middle illustrates the amount of natural gas saved after optimization using the method of the present invention. It can be seen that the method of the present invention can achieve the purpose of reducing the amount of natural gas required for equipment operation.

[0127] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment, characterized in that: include: 1) Use the modeling coating operation plan to build an online monitoring concentration prediction model. The specific process is as follows: S1-1: Record the modeling and painting work plan: The coating operation plan S consists of N sections of working conditions S i Composition, i=1, ..., N, the recorded modeling coating operation plan data includes the number of sections, the working condition data of each section, and the online monitoring concentration curve of the coating operation plan; S1-2: Correlate the working condition data of each working condition with each band in the online monitoring concentration curve of the coating operation plan; S1-3: Perform curve fitting for the online monitoring concentration of each working condition: ① Any i-th working condition S i The online monitoring concentration is fitted using the logarithmic Gaussian function of formula (1): In formula (1), t represents the working condition S i A moment in time; represents the online monitoring concentration at time t; e represents the natural logarithm; t i Indicates the working condition S i The time difference between the start time of the current painting operation and the planned start time of the current painting operation; ln(*) represents the natural logarithmic function; K i , μ i , σ i 2 is the characteristic parameter of the logarithmic Gaussian function, calculated from the Gaussian curve; ② Define the entire coating operation plan S Online monitoring concentration can be through N working conditions S i The concentrations of are superimposed and expressed as: In formula (2), It represents the online monitoring concentration of the coating operation plan S; S1-4: Constructing online monitoring concentration prediction model: From formula (1), we can get S for each working condition: i A Gaussian curve will be fitted, thus obtaining a set of characteristic parameters K i , μ i , σ i 2 , then the N working conditions of the entire coating operation plan S obtain the characteristic parameter set {K i , μ i , σ i 2 }, i=1,...,N; Construct a set of conditions {S i }, i = 1, ..., each working condition and characteristic parameter set in N {K i , μ i , σ i 2 }, i=1,..., the mapping relationship g of each group of characteristic parameters in N is expressed as follows: According to formula (2), the following online monitoring concentration prediction model for coating operation plan is constructed: In formula (4), It represents the prediction result of the online monitoring concentration of the current coating operation plan; the current coating operation plan is divided into M working conditions S i , i=1,...,M; Indicates the working condition S in the current coating operation plan i The prediction result of the online monitoring concentration is based on the working condition S in the current coating operation plan. i A Gaussian curve drawn by a set of characteristic parameters of a logarithmic Gaussian function obtained according to formula (3); 2) Use the modeled coating operation plan and standard reference concentration to build a calibration correction model, as shown below: In formula (5), C O Indicates online monitoring concentration; C L represents the standard reference concentration, and h represents the mapping relationship between the online monitoring concentration and the standard reference concentration; 3) obtaining the current coating operation plan, and obtaining a prediction curve of the online monitoring concentration through the online monitoring concentration prediction model; 4) Verifying the prediction curve of the online monitoring concentration by the verification correction model to obtain an accurate concentration prediction curve; 5) Based on the accurate concentration prediction curve and the natural gas consumption calculation rules, calculate the natural gas consumption.

2. The method for calculating the gas intake configuration of the natural gas pipeline in the waste gas treatment according to claim 1, characterized in that: in, The mapping relationship g between the working condition and the characteristic parameters in step S1-4 is constructed using the XGBoost model.

3. The method for calculating the gas intake configuration of the natural gas pipeline in the waste gas treatment according to claim 1, characterized in that: in, The standard reference concentration in step 2) refers to the monitoring concentration obtained by exhaust gas sampling and analysis at the inlet of the exhaust main pipe by a third-party monitoring agency while obtaining the online monitoring concentration of the modeled coating operation plan.

4. The method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment according to claim 3, characterized in that: in, The mapping relationship h between the online monitoring concentration and the standard reference concentration of the modeled coating operation plan is constructed using the GPR model.

5. The method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment according to claim 3, characterized in that: in, Step 4) is specifically as follows: taking the predicted value of the online monitoring concentration of the current coating operation plan as the input item, using the mapping relationship h of the calibration correction model to output the corresponding standard reference concentration, and the concentration curve represented by the output standard reference concentration is the accurate concentration prediction curve.

6. The method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment according to claim 1, characterized in that: in, The specific process of step 5) is as follows; S5-1: Divide the painting stage and curing stage according to the accurate concentration prediction curve; S5-2: Calculate the air volume of the main engine: In formula (6), L1 represents the design value of the main fan air volume; Indicates the main fan air volume during actual operation; S5-3: Calculate the air volume range of the desorption fan: In formula (7), ρ U and ρ L is the design parameter of the equipment; S5-4: Concentration ratio The upper and lower limits of the concentration ratio are calculated based on the ratio of the main fan air volume to the desorption fan air volume. S5-5: Calculate the concentration C on the accurate concentration prediction curve L Critical point C that does not require natural gas combustion T : In formula (9), It is the concentration of VOCs that the RTO equipment maintains for spontaneous combustion; S5-6: Calculate the natural gas consumption F: When C L >C T When C L ≤C T When , the natural gas consumption is the same as that under the condition without optimization; S5-7: According to the critical point C T Calculate the gas supply stop time T Start and gas supply start time T End ; S5-8: Calculate the actual concentration ratio R during the operation of the RTO equipment True : In formula (10), F refers to the amount of natural gas used.

7. The method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment according to claim 6, characterized in that: in, The division rules of step S5-1 are as follows: The 1 / 2 time point where the extreme value of the last peak of the accurate concentration prediction curve occurs is taken as the dividing line. The time period before this is the painting stage, and the time period after this is the curing stage.

8. The method for calculating the gas intake configuration of a natural gas pipeline in waste gas treatment according to claim 6, characterized in that: in, The gas supply stop time T in step S5-5 Start and gas supply start time T End The calculation is as follows: In the accurate concentration prediction curve with time as the horizontal axis and organic waste gas concentration as the vertical axis, the critical point C is drawn. T , critical point C T is a straight line parallel to the horizontal axis, which forms an intersection with the accurate concentration prediction curve. The situation of the intersection is as follows: If the slope of the accurate concentration prediction curve at the intersection is positive, then the time point of the horizontal coordinate corresponding to the intersection is the gas supply stop time point T End ; If the slope of the accurate concentration prediction curve at the intersection is negative, then the time point on the abscissa corresponding to the intersection is the gas supply start time T Start .

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