A method and system for purifying waste incineration flue gas based on a DCS system

Abstract

The present application relates to a method and system for purifying waste incineration flue gas based on a DCS system, and relates to the field of waste treatment technologies. The method includes obtaining the unit flow rate of incineration flue gas and the unit flow rate of characteristic gases; determining the characteristic flow rate ratio of each characteristic gas according to the unit flow rate of characteristic gases and the unit flow rate of incineration flue gas; combining according to each characteristic flow rate ratio to determine a gas distribution combination; establishing a detection interval with a width of a preset detection duration with the current time point as the rear end point on a preset time axis, and determining a similar distribution combination according to the gas distribution combination in the detection interval; determining the corresponding unit caustic addition amount according to each similar distribution combination in the detection interval, and calculating according to all the unit caustic addition amounts to determine the simulated caustic addition amount; controlling a preset caustic addition device to add alkaline materials to the inside of the absorption tower according to the simulated caustic addition amount. The present application has the effect of reducing the waste of materials for flue gas purification.

Description

Technical Field

[0001] The present application relates to the field of waste treatment technologies, and in particular, to a method and system for purifying waste incineration flue gas based on a DCS system. Background Art

[0002] The DCS system, namely the distributed control system, is a control system widely used in the field of industrial automation. It has the characteristics of distributed control and centralized management, and can realize real-time monitoring, control and management of the production process. The application of the DCS system in the purification of waste incineration flue gas can realize real-time monitoring, control and management of the purification process, ensuring that the flue gas emissions meet environmental protection standards.

[0003] In the related technologies, when purifying the flue gas of waste incineration, a relatively mature process is the semi-dry method + dry method + bag filter + activated carbon process. Among them, the main equipment used in the semi-dry method is the deacidification absorption tower. By spraying an alkaline absorption liquid, such as sodium hydroxide (NaOH) solution or calcium hydroxide (Ca(OH)2) solution, inside the absorption tower, a chemical reaction occurs with the acidic gases in the flue gas, thereby achieving deacidification.

[0004] In the above-mentioned related technologies, when performing flue gas deacidification treatment, in order to ensure that the flue gas treatment can meet the standards, the dosing of purification materials such as lime slurry, activated carbon, and ammonia water is often increased to the maximum. Although it can meet the purification requirements, since the composition of the waste incineration is not the same at any time, the composition of the generated flue gas is not fixed. Therefore, it may cause waste of materials, thereby increasing the overall cost of waste incineration flue gas purification, and there is still room for improvement. Summary of the Invention

[0005] In order to reduce the waste of materials in flue gas purification, the present application provides a method and system for purifying waste incineration flue gas based on a DCS system.

[0006] In a first aspect, the present application provides a method for purifying waste incineration flue gas based on a DCS system, adopting the following technical solution:

[0007] A method for purifying waste incineration flue gas based on a DCS system includes:

[0008] Obtaining the unit flow rate of the incineration flue gas and the unit flow rate of the characteristic gas at the inlet of the absorption tower;

[0009] Calculating according to the unit flow rate of the characteristic gas and the unit flow rate of the incineration flue gas to determine the characteristic flow rate ratio of each characteristic gas, where the characteristic gas is the acidic gas with a relatively large content in the specified flue gas;

[0010] Combining according to each characteristic flow rate ratio to determine the gas distribution combination;

[0011] On a preset time axis, a detection interval with a width of a preset detection duration is established with the current time point as the rear endpoint, and similar distribution combinations are determined according to the gas distribution combinations in the detection interval;

[0012] In the detection interval, corresponding unit caustic addition amounts are determined according to each similar distribution combination, and a simulated caustic addition amount is determined by calculating based on all the unit caustic addition amounts;

[0013] Based on the simulated caustic addition amount, a preset caustic addition device is controlled to add alkaline materials inside the absorption tower.

[0014] Optionally, the step of determining similar distribution combinations according to the gas distribution combinations in the detection interval includes:

[0015] The gas distribution combinations determined within the detection interval are defined as historical distribution combinations, and the characteristic flow rate ratios corresponding to the historical distribution combinations are defined as historical flow rate ratios;

[0016] In the same characteristic gas, a flow similarity ratio is determined by calculating based on the historical flow rate ratio and the current characteristic flow rate ratio;

[0017] According to the preset parameter matching relationship, similar calculation parameters corresponding to the flow similarity ratio are determined;

[0018] A summation calculation is performed based on all the similar calculation parameters to determine an overall similarity value, and the historical distribution combinations with the overall similarity value greater than the preset benchmark requirement value are defined as similar distribution combinations.

[0019] Optionally, the step of determining a simulated caustic addition amount by calculating based on all the unit caustic addition amounts includes:

[0020] According to the preset consumption matching relationship, the corresponding alkaline consumption amounts of each characteristic gas are determined;

[0021] Based on all the historical flow rate ratios and the corresponding alkaline consumption amounts, characteristic consumption amounts are calculated, and a difference calculation is performed between the unit caustic addition amount and the characteristic consumption amount to determine the excess consumption amount of the excess gas, where the excess gas is the acidic gas that can be treated by the alkaline material other than the characteristic gas;

[0022] Based on the flow similarity ratio of each characteristic gas and the excess consumption amount, the theoretical consumption amount of the current excess gas is determined;

[0023] Based on all the theoretical consumption amounts determined in the same similar distribution combination, a mean value calculation is performed to determine the theoretical excess average amount;

[0024] Calculate according to all theoretical excess amounts to determine the feasible excess amount, and calculate according to the feasible excess amount, the current characteristic flow rate ratio, and the corresponding alkaline consumption amount to determine the simulated alkali addition amount.

[0025] Optionally, the steps of calculating according to all theoretical excess amounts to determine the feasible excess amount include:

[0026] Randomly select a theoretical excess amount from all theoretical excess amounts as the standard excess amount, and define the remaining theoretical excess amounts as comparison excess amounts;

[0027] Calculate according to the standard excess amount and all comparison excess amounts to determine the separation parameter value;

[0028] Determine the separation parameter value with the smallest value according to the preset sorting rule, and define the standard excess amount corresponding to this separation parameter value as the central excess amount;

[0029] Construct a proximity interval according to the central excess amount and the preset proximity parameter, and define the theoretical excess amounts within the proximity interval as effective excess amounts, and calculate the average value according to all effective excess amounts to determine the feasible excess amount.

[0030] Optionally, the steps of controlling the preset alkali addition equipment to add alkaline materials to the inside of the absorption tower according to the simulated alkali addition amount include:

[0031] Calculate according to the simulated alkali addition amount and the preset unit spraying amount to determine the required number of equipment, and calculate according to the simulated alkali addition amount and the required number of equipment to determine the single-unit alkali addition amount;

[0032] Combine according to the required number of equipment among all alkali addition equipment to form an available equipment combination;

[0033] Obtain the spraying operation duration of each alkali addition equipment in the available equipment combination;

[0034] Determine the corresponding single-unit appropriate value of the spraying operation duration according to the preset appropriate matching relationship, and calculate the sum of all single-unit appropriate values to determine the overall appropriate value of the available equipment combination;

[0035] Determine the overall appropriate value with the largest value according to the sorting rule, and define the available equipment combination corresponding to this overall appropriate value as the effective equipment combination, and control the alkali addition equipment in the effective equipment combination to add alkaline materials according to the single-unit alkali addition amount.

[0036] Optionally, after determining the overall appropriate value, the waste incineration flue gas purification method based on the DCS system further includes:

[0037] Determine whether there are at least two combinations of available devices with the same and maximum overall suitability values;

[0038] If there are not at least two combinations of available devices with the same and maximum overall suitability values, define the effective device combination according to the combination of available devices corresponding to the overall suitability value with the largest numerical value;

[0039] If there are at least two combinations of available devices with the same and maximum overall suitability values, define the combination of available devices corresponding to the overall suitability value with the largest numerical value as the alternative device combination, and sort the caustic adding devices in each alternative device combination to determine the device position order;

[0040] Determine the device separation distance between adjacent caustic adding devices according to the device position order, and calculate the difference based on each device separation distance and the preset standard separation distance to determine the difference separation distance;

[0041] Determine the excellent parameters corresponding to the difference separation distance according to the preset distance matching relationship, and calculate the average value of each excellent parameter to determine the optimal parameter;

[0042] Determine the optimal parameter with the largest numerical value according to the sorting rule, and define the alternative device combination corresponding to the optimal parameter as the effective device combination.

[0043] Optionally, after determining the optimal parameter with the largest numerical value, the method for purifying waste incineration flue gas based on the DCS system further includes:

[0044] Judge whether the optimal parameter with the largest numerical value is greater than the preset reference parameter;

[0045] If the optimal parameter with the largest numerical value is greater than the reference parameter, define the alternative device combination corresponding to the optimal parameter as the effective device combination;

[0046] If the optimal parameter with the largest numerical value is not greater than the reference parameter, eliminate the combination of available devices corresponding to the overall suitability value, and re-determine the combination of available devices with the largest overall suitability value.

[0047] In a second aspect, the present application provides a waste incineration flue gas purification system based on the DCS system, adopting the following technical solutions:

[0048] A waste incineration flue gas purification system based on the DCS system includes:

[0049] An acquisition module, configured to acquire the unit flow rate of incineration flue gas and the unit flow rate of characteristic gas at the inlet of the absorption tower;

[0050] A processing module, connected to the acquisition module, for storing and processing information;

[0051] The processing module calculates based on the unit flow rate of the characteristic gas and the unit flow rate of the incineration flue gas to determine the proportion of the characteristic flow rate of each characteristic gas, where the characteristic gas is the acidic gas with a relatively large content in the specified flue gas;

[0052] The processing module combines according to the proportion of each characteristic flow rate to determine the gas distribution combination;

[0053] The processing module establishes a detection interval with a width of a preset detection duration with the current time point as the rear end point on the preset time axis, and determines the similar distribution combination according to the gas distribution combination in the detection interval;

[0054] The processing module determines the corresponding unit caustic addition amount according to each similar distribution combination in the detection interval, and calculates according to all the unit caustic addition amounts to determine the simulated caustic addition amount;

[0055] The processing module controls the preset caustic addition equipment to add alkaline materials to the inside of the absorption tower according to the simulated caustic addition amount.

[0056] In summary, the present application includes at least one of the following beneficial technical effects:

[0057] 1. When treating the flue gas generated by garbage incineration, the amount of alkaline materials required as a whole can be determined by analyzing the flow rate of some characteristic gases, so that the added alkaline materials meet the requirements, reducing the occurrence of excessive input of alkaline materials, and thus reducing the waste of materials for flue gas purification;

[0058] 2. By analyzing the data of the caustic consumption in the historical situation, the amount of alkaline materials required in the current situation can be determined more accurately, which is convenient for subsequent feeding and use;

[0059] 3. When adding alkaline materials, the specific conditions of each caustic addition equipment can be analyzed to make the overall addition effect better. Description of the Drawings

[0060] Figure 1 is a flowchart of a method for purifying garbage incineration flue gas based on a DCS system.

[0061] Figure 2 is a module flowchart of a method for purifying garbage incineration flue gas based on a DCS system. Detailed Embodiment

[0062] In order to make the purpose, technical solution and advantages of the present application clearer, the following is further described in detail in combination with Figure 1 - Figure 2 and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0063] The embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings of the specification.

[0064] The embodiments of the present application disclose a method for purifying waste incineration flue gas based on a DCS system. Referring to Figure 1 , the method flow of the method for purifying waste incineration flue gas based on a DCS system includes the following steps:

[0065] Step S100: Obtain the unit flow rate of incineration flue gas and the unit flow rate of characteristic gas at the inlet of the absorption tower.

[0066] The unit flow rate of incineration flue gas is the flow rate of the flue gas entering the interior of the absorption tower from the inlet of the absorption tower per unit time, which can be determined by installing a flow meter at the inlet of the absorption tower; the unit flow rate of characteristic gas is the flow rate of the characteristic gas entering the interior of the absorption tower from the inlet of the absorption tower per unit time. This characteristic gas is the acidic gas with a relatively large content in the flue gas specified by the staff in advance, such as sulfur dioxide, hydrogen chloride, etc. This flow rate can be obtained by installing a specific flow meter at the inlet of the absorption tower that can detect a single characteristic gas, that is, a corresponding flow meter should be installed at the inlet of the absorption tower for each set characteristic gas.

[0067] Step S101: Calculate according to the unit flow rate of characteristic gas and the unit flow rate of incineration flue gas to determine the proportion of the characteristic flow rate of each characteristic gas, where the characteristic gas is the acidic gas with a relatively large content in the specified flue gas.

[0068] The proportion of characteristic flow rate is the ratio of a single characteristic gas to the flue gas, which is determined by dividing the unit flow rate of characteristic gas by the unit flow rate of incineration flue gas.

[0069] Step S102: Combine according to the proportions of each characteristic flow rate to determine the gas distribution combination.

[0070] The gas distribution combination is the combination composed of the determined characteristic gases, such as 2% sulfur dioxide + 1% hydrogen chloride.

[0071] Step S103: Establish a detection interval with a width of a preset detection duration with the current time point as the rear end point on the preset time axis, and determine the similar distribution combination according to the gas distribution combination in the detection interval.

[0072] The time axis is a coordinate axis formed by combining each time point. This coordinate axis points from the passed time points to the time points that have not yet been reached. The detection duration is the duration set by the staff for obtaining historical incineration data, such as 1 month. A detection interval is established to facilitate the acquisition and analysis of data within the detection duration. The similar distribution combination is the gas distribution combination in the detection interval that is relatively similar to the current gas distribution combination. The gas distribution combination that can be considered completely similar is the similar distribution combination, and it can also be determined according to steps S200 - S203.

[0073] Step S104: In the detection interval, determine the corresponding unit alkali addition amount according to each similar distribution combination, and calculate based on all the unit alkali addition amounts to determine the simulated alkali addition amount.

[0074] The unit addition and subtraction amount is the amount of alkaline material added when effectively treating the flue gas with a unit flow rate per unit time in the historical situation, which can be obtained by acquiring historical flue gas purification data. The simulated alkali addition amount is the amount of alkaline material required to effectively treat the flue gas with a unit flow rate per unit time in the current situation, which can be obtained by calculating the average value of all the unit alkali addition amounts, or can also be determined according to steps S300 - S304.

[0075] Step S105: Control the preset alkali addition device to add alkaline material into the absorption tower according to the simulated alkali addition amount.

[0076] The alkali addition device is a device installed inside the absorption tower and arranged at intervals in the height direction of the absorption tower for spraying alkaline material. Through the alkali addition device, alkaline material with the simulated alkali addition amount can be effectively sprayed into the absorption tower, thereby realizing the purification treatment of the flue gas.

[0077] The steps for determining the similar distribution combination according to the gas distribution combination in the detection interval include:

[0078] Step S200: Define the gas distribution combination determined within the detection interval as the historical distribution combination, and define the corresponding characteristic flow rate ratio of the historical distribution combination as the historical flow rate ratio.

[0079] Defining the historical distribution combination and the historical flow rate ratio is to distinguish different data for subsequent analysis.

[0080] Step S201: Calculate according to the historical flow rate ratio and the current characteristic flow rate ratio within the same characteristic gas to determine the flow similarity ratio.

[0081] The flow similarity ratio is the similarity value of the characteristic flow rate ratios obtained for the same characteristic gas at two time points. The calculation formula is , where is the flow similarity ratio, is the historical flow proportion, is the current characteristic flow proportion.

[0082] Step S202: Determine the similarity calculation parameters corresponding to the flow similarity proportion according to the preset parameter matching relationship.

[0083] The similarity calculation parameter is a parameter reflecting the similarity degree value of two data. The larger this value, the more similar the two data are. The larger the flow similarity proportion, the larger the corresponding similarity calculation parameter. The parameter matching relationship between the two is determined by the staff through multiple tests in advance.

[0084] Step S203: Perform a summation calculation based on all the similarity calculation parameters to determine the overall similarity value, and define the historical distribution combination with the overall similarity value greater than the preset benchmark requirement value as the similarity distribution combination.

[0085] The overall similarity value is the sum of the similarity calculation parameters determined by all characteristic gases. The benchmark requirement value is the minimum overall similarity value that needs to be satisfied when the staff determines that the similarity degree of two combinations is high. When the overall similarity value is greater than the benchmark requirement value, it indicates that the corresponding historical distribution combination is highly similar to the current gas distribution combination. At this time, it can be defined as the similarity distribution combination.

[0086] The steps for calculating the simulated alkali addition amount according to all the unit alkali addition amounts include:

[0087] Step S300: Determine the corresponding alkaline consumption of each characteristic gas according to the preset consumption matching relationship.

[0088] The alkaline consumption is the amount of alkaline material required to effectively process a unit volume of characteristic gas in theory. Different characteristic gases have different corresponding alkaline consumptions due to different reaction formulas. The consumption matching relationship between the two can be determined by the staff through multiple tests in advance.

[0089] Step S301: Calculate based on all the historical flow proportions and the corresponding alkaline consumptions to determine the characteristic consumption, and perform a difference calculation based on the unit alkali addition amount and the characteristic consumption to determine the excess consumption of the excess gas, where the excess gas is the acidic gas that can be treated by the alkaline material other than the characteristic gas.

[0090] The characteristic consumption is the amount of alkaline material required by all characteristic gases, which is determined by multiplying the historical flow proportion of each characteristic gas by the corresponding alkaline consumption and then adding them all together; the excess consumption is the amount of alkaline material consumed by the excess gas, where the excess gas is the acidic gas that can be treated by the alkaline material other than the characteristic gas, that is, each acidic gas with a small content, and is determined by subtracting the characteristic consumption from the unit alkali addition amount.

[0091] Step S302: Calculate based on the flow similarity ratio of each characteristic gas and the excess consumption to determine the theoretical consumption of the current excess gas.

[0092] Generally, the excess gas is generated simultaneously with the characteristic gas. Therefore, a large content of the characteristic gas also indicates a large content of the excess gas, and the two can be shown in direct proportion; the ratio of the same characteristic gas under two combinations can be obtained through the flow similarity ratio. Therefore, the theoretical consumption of the excess gas can be determined based on this ratio.

[0093] Step S303: Calculate the mean value based on all the determined theoretical consumptions in the same similarity distribution combination to determine the theoretical excess average.

[0094] There are multiple characteristic gases corresponding to the same similarity distribution combination, and each characteristic gas will determine a theoretical consumption. At this time, the theoretical excess average representing the amount of alkaline material required for the current excess gas can be determined by calculating the mean value of all the theoretical consumptions.

[0095] Step S304: Calculate based on all the theoretical excess averages to determine the feasible excess average, and calculate based on the feasible excess average, the current characteristic flow ratio, and the corresponding alkaline consumption to determine the simulated alkali addition amount.

[0096] The feasible excess average is the amount of alkaline material that would be applied to the excess gas in the current situation under theoretical conditions after referring to all similarity distribution combinations. The calculation method can be obtained by calculating the mean value of all the theoretical excess averages, or can be determined by the method of Step S400 - Step S403; the amount of alkaline material required for the current characteristic gas can be obtained by multiplying the current characteristic flow ratio by the corresponding alkaline consumption, and then adding this value to the feasible excess average to obtain the overall required simulated alkali addition amount.

[0097] The steps of calculating based on all the theoretical excess averages to determine the feasible excess average include:

[0098] Step S400: Randomly select one of all the theoretical excess averages as the standard excess average, and define the remaining theoretical excess averages as the comparison excess averages.

[0099] Define the standard excess average and the comparison excess averages to distinguish different data for subsequent analysis.

[0100] Step S401: Calculate based on the standard excess average and all the comparison excess averages to determine the separation parameter value.

[0101] The separation parameter value is a value that reflects the distance between the currently determined standard redundant average and the other comparative redundant averages. The smaller this value, the more representative the standard redundant average is of the other comparative redundant averages. The calculation formula is , where is the separation parameter value, is the standard redundant average, is the th comparative redundant average, is the total number of comparative redundant averages.

[0102] Step S402: Determine the separation parameter value with the smallest value according to the preset sorting rule, and define the standard redundant average corresponding to this separation parameter value as the central redundant average.

[0103] The sorting rule is a method set by the staff to sort the numerical values, such as the bubble sort method. Through the sorting rule, the separation parameter value with the smallest value can be determined, that is, the standard redundant average corresponding to this separation parameter value is the most representative of the other comparative redundant averages. At this time, it is defined as the central redundant average to distinguish different standard redundant averages for subsequent analysis.

[0104] Step S403: Construct a proximity interval according to the central redundant average and the preset proximity parameter, and define the theoretical redundant averages within the proximity interval as effective redundant averages, and calculate the mean value based on all the effective redundant averages to determine the feasible redundant average.

[0105] The proximity parameter is the maximum interval parameter allowed by the staff when determining that it is relatively close to the central redundant average. The proximity interval is the interval in which the values relatively close to the central redundant average need to be located. The upper and lower endpoints of this interval are determined by adding and subtracting the proximity parameter from the central redundant average respectively; defining the effective redundant average to eliminate some data with data errors, so that a more accurate feasible redundant average can be obtained by calculating the mean value based on the effective redundant averages.

[0106] The steps of controlling the addition of alkaline materials inside the absorption tower according to the simulated caustic addition amount by preset caustic addition equipment include:

[0107] Step S500: Calculate according to the simulated caustic addition amount and the preset unit spray amount to determine the required number of equipment, and calculate according to the simulated caustic addition amount and the required number of equipment to determine the monomer caustic addition amount.

[0108] The unit spraying amount is the amount of alkaline material that a single alkali addition device can spray per unit time. The required number of devices is the number of alkali addition devices required for adding the simulated alkali addition amount of alkaline material, which is determined by dividing the simulated alkali addition amount by the unit spraying amount and rounding up; the unit alkali addition amount is the amount of alkali addition required when adding alkaline material using the required number of alkali addition devices, which is determined by dividing the simulated alkali addition amount by the required number of devices.

[0109] Step S501: Combine all the alkali addition devices according to the required number of devices to form an available device combination.

[0110] The available device combination is the combination formed by each alkali addition device. For example, if the required number of devices is 2, and there are three alkali addition devices A, B, and C at this time, the available device combinations that can be formed include AB, AC, and BC.

[0111] Step S502: Obtain the spraying operation duration of each alkali addition device in the available device combination.

[0112] The spraying operation duration is the total duration of the alkali addition device for use operation.

[0113] Step S503: Determine the corresponding single appropriate value according to the preset appropriate matching relationship for the spraying operation duration, and perform a summation calculation based on all the single appropriate values to determine the overall appropriate value of the available device combination.

[0114] The single appropriate value is a value reflecting the appropriateness of selecting this alkali addition device. The shorter the spraying operation duration, the newer the device, the more it can be continuously used, and the larger the corresponding single appropriate value. The appropriate matching relationship between the two is determined by the staff in advance and will not be elaborated here; the overall appropriate value is the sum of all single appropriate values.

[0115] Step S504: Determine the overall appropriate value with the largest value according to the sorting rule, and define the available device combination corresponding to this overall appropriate value as the effective device combination, and control the alkali addition devices in the effective device combination to add alkaline material according to the single alkali addition amount.

[0116] Through the sorting rule, the overall appropriate value with the largest value can be determined, that is, the alkali addition devices in the available device combination corresponding to this overall appropriate value have the best use effect. At this time, it is defined as the effective device combination to distinguish different available device combinations, so as to control the corresponding alkali addition devices to perform operations.

[0117] After the overall appropriate value is determined, the method for purifying waste incineration flue gas based on the DCS system further includes:

[0118] Step S600: Determine whether there are at least two available device combinations with the same and largest overall appropriate value.

[0119] The purpose of the judgment is to find out whether there are multiple available device combinations that meet the requirements.

[0120] Step S6001: If there are not at least two available device combinations with the same and maximum overall suitability value, define the effective device combination according to the available device combination corresponding to the overall suitability value with the largest value.

[0121] When there are not at least two available device combinations with the same and maximum overall suitability value, it means that there is only a unique available device combination that meets the requirements. At this time, it can be determined as the effective device combination.

[0122] Step S6002: If there are at least two available device combinations with the same and maximum overall suitability value, define the available device combination corresponding to the overall suitability value with the largest value as the alternative device combination, and sort the caustic adding devices in each alternative device combination to determine the device position order.

[0123] When there are at least two available device combinations with the same and maximum overall suitability value, it means that there are multiple available device combinations that can be used as effective device combinations. At this time, further analysis is required; define the alternative device combination to distinguish different available device combinations for subsequent analysis; the device position order is the sorting order of each caustic adding device, and this order can be sorted from top to bottom or from bottom to top in the absorption tower.

[0124] Step S601: Determine the distance between adjacent caustic adding devices according to the device position order, and calculate the difference between each device distance and the preset standard distance to determine the difference distance.

[0125] The device distance is the position distance between adjacent caustic adding devices in the device position order. The standard distance is the distance value set by the staff when it is determined that the alkaline material sprayed can react completely with the acidic gas better. The difference distance is the difference between the device distance and the standard distance, and this difference is an absolute value.

[0126] Step S602: Determine the excellent parameter corresponding to the difference distance according to the preset distance matching relationship, and calculate the average value of each excellent parameter to determine the preferred parameter.

[0127] The excellent parameter is a parameter that reflects the appropriate value of the distance between two devices. When the difference distance is smaller, it means that the distance between the two devices is more appropriate, and the corresponding excellent parameter is also larger. The distance matching relationship between the two is determined and entered by the staff in advance; the preferred parameter is the average value of all the determined excellent parameters.

[0128] Step S603: Determine the optimal parameter with the largest value according to the sorting rule, and define the alternative equipment combination corresponding to this optimal parameter as the effective equipment combination.

[0129] Through the sorting rule, the optimal parameter with the largest value can be determined, that is, the alternative equipment combination corresponding at this time has the best use effect, and it can be determined as the effective equipment combination at this time.

[0130] After the optimal parameter with the largest value is determined, the waste incineration flue gas purification method based on the DCS system further includes:

[0131] Step S700: Determine whether the optimal parameter with the largest value is greater than the preset reference parameter.

[0132] The reference parameter is the minimum optimal parameter that needs to be satisfied for the staff to determine that the alkali addition equipment can perform spray operation well. The purpose of the judgment is to know whether the selected combination meets the use requirements.

[0133] Step S7001: If the optimal parameter with the largest value is greater than the reference parameter, define the alternative equipment combination corresponding to this optimal parameter as the effective equipment combination.

[0134] When the optimal parameter with the largest value is greater than the reference parameter, it means that the determined combination meets the requirements, and at this time, the effective equipment combination can be determined normally.

[0135] Step S7002: If the optimal parameter with the largest value is not greater than the reference parameter, eliminate the available equipment combination corresponding to this overall appropriate value, and re-determine the available equipment combination with the largest overall appropriate value.

[0136] When the optimal parameter with the largest value is not greater than the reference parameter, it means that the currently determined combination cannot meet the use requirements. At this time, re-determine the available equipment combination with the largest overall appropriate value for re-analysis.

[0137] Refer to Figure 2 Based on the same inventive concept, an embodiment of the present invention provides a waste incineration flue gas purification system based on the DCS system, including:

[0138] An acquisition module for acquiring the unit flow rate of the incineration flue gas and the unit flow rate of the characteristic gas at the inlet of the absorption tower;

[0139] A processing module, connected to the acquisition module, for storing and processing information;

[0140] The processing module calculates according to the unit flow rate of the characteristic gas and the unit flow rate of the incineration flue gas to determine the characteristic flow rate ratio of each characteristic gas, where the characteristic gas is the acidic gas with a relatively large content in the specified flue gas;

[0141] The processing module combines according to the proportion of each characteristic flow rate to determine the gas distribution combination;

[0142] The processing module establishes a detection interval with a width of a preset detection duration with the current time point as the backend point on the preset time axis, and determines the similar distribution combination according to the gas distribution combination in the detection interval;

[0143] The processing module determines the corresponding unit caustic addition amount according to each similar distribution combination in the detection interval, and calculates according to all the unit caustic addition amounts to determine the simulated caustic addition amount;

[0144] The processing module controls the preset caustic addition device to add alkaline materials to the inside of the absorption tower according to the simulated caustic addition amount;

[0145] The similar distribution combination determination module is used to determine the similar distribution combination among all historical distribution combinations;

[0146] The simulated caustic addition amount determination module is used to determine and process the simulated caustic addition amount in the current situation;

[0147] The feasible surplus average amount determination module determines the feasible surplus average amount according to all the theoretical surplus average amounts;

[0148] The material addition control module is used to determine and control the caustic addition device for adding alkaline materials;

[0149] The available device combination screening module is used to screen multiple available device combinations that meet the requirements;

[0150] The unavailable device combination elimination module is used to eliminate the available device combinations that cannot meet the requirements.

[0151] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the above division of each functional module is used as an example. In actual applications, the above functions can be allocated to different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. The specific working processes of the system, device and unit described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated here.

Claims

1. A waste incineration flue gas purification method based on a DCS system, characterized in that: include: Obtain the unit flow rate of incineration flue gas and the unit flow rate of characteristic gas at the entrance of the absorption tower; Calculate the characteristic flow ratio of each characteristic gas based on the characteristic gas unit flow rate and the incineration flue gas unit flow rate, where the characteristic gas is the acid gas with a larger content in the designated flue gas; Combining the gas distribution combination according to the proportion of each characteristic flow rate; A detection interval with a width of a preset detection time length is established on a preset time axis with the current time point as the rear end point, and a similar distribution combination is determined in the detection interval according to the gas distribution combination; Determine the corresponding unit alkali addition amount according to each similar distribution combination in the detection interval, and calculate according to all the unit alkali addition amounts to determine the simulated alkali addition amount; According to the simulated alkali addition amount, the preset alkali addition equipment is controlled to add alkaline material into the absorption tower; The step of determining a similar distribution combination according to the gas distribution combination in the detection interval includes: The gas distribution combination determined in the detection interval is defined as the historical distribution combination, and the characteristic flow ratio corresponding to the historical distribution combination is defined as the historical flow ratio; In the same characteristic gas, the flow similarity ratio is determined by calculating the historical flow ratio and the current characteristic flow ratio; Determine similarity calculation parameters corresponding to traffic similarity ratios based on preset parameter matching relationships; Perform sum calculation according to all similarity calculation parameters to determine the overall similarity value, and define the historical distribution combination whose overall similarity value is greater than the preset benchmark demand value as the similarity distribution combination; The steps for calculating the simulated alkali addition amount based on all the unit alkali addition amounts include: Determine the alkalinity consumption corresponding to each characteristic gas according to the preset consumption matching relationship; The characteristic consumption is determined by calculating the percentage of all historical flows and the corresponding alkaline consumption, and the excess consumption of excess gas is determined by performing a difference calculation based on the unit alkali addition amount and the characteristic consumption, wherein the excess gas is the acid gas other than the characteristic gas that can be treated by alkaline materials; The theoretical consumption of the current excess gas is determined by calculating the similar proportion of the flow rate of each characteristic gas and the excess consumption; The theoretical excess mean is determined by averaging all theoretical consumptions determined in the same similar distribution combination; The feasible excess average is calculated based on all theoretical excess averages, and the simulated alkali addition amount is determined based on the feasible excess average, the current characteristic flow ratio and the corresponding alkali consumption.

2. The waste incineration flue gas purification method based on the DCS system according to claim 1 is characterized in that: The steps for calculating the feasible excess mean based on all theoretical excess means include: A theoretical excess mean is randomly selected from all theoretical excess means as the standard excess mean, and the remaining theoretical excess means are defined as comparative excess means; The interval parameter value is determined by calculating the standard excess mean and all the comparative excess means; Determine the minimum interval parameter value according to a preset sorting rule, and define the standard excess mean corresponding to the interval parameter value as the central excess mean; A similar interval is constructed based on the central excess mean and preset similar parameters, and the theoretical excess mean in the similar interval is defined as the effective excess mean, and the mean is calculated based on all the effective excess means to determine the feasible excess mean.

3. The waste incineration flue gas purification method based on the DCS system according to claim 1 is characterized in that: The steps of controlling the preset alkali adding equipment to add alkaline material to the inside of the absorption tower according to the simulated alkali addition amount include: The required number of equipment is determined by calculation based on the simulated alkali addition amount and the preset unit spraying amount, and the monomer alkali addition amount is determined by calculation based on the simulated alkali addition amount and the required number of equipment; Combine all alkali adding equipment according to the required number of equipment to form an available equipment combination; Obtain the spraying operation time of each alkali adding equipment in the available equipment combination; Determine the monomer suitable value corresponding to the duration of the spraying operation according to the preset suitable matching relationship, and sum up all the monomer suitable values ​​to determine the overall suitable value of the available equipment combination; The overall suitable value with the largest value is determined according to the sorting rules, and the available equipment combination corresponding to the overall suitable value is defined as the effective equipment combination, and the alkali adding equipment in the effective equipment combination is controlled to add alkaline material according to the monomer alkali addition amount.

4. The method for purifying waste incineration flue gas based on the DCS system according to claim 3 is characterized in that: After the overall appropriate value is determined, the waste incineration flue gas purification method based on the DCS system also includes: Determine whether there are at least two available equipment combinations with the same overall fitness value and the largest value; If there are not at least two available device combinations with the same overall fitness value and the largest value, then the valid device combination is defined according to the available device combination corresponding to the overall fitness value with the largest value; If there are at least two available equipment combinations with the same and largest overall fitness values, the available equipment combination corresponding to the largest overall fitness value is defined as the alternative equipment combination, and the alkali-adding equipment in each alternative equipment combination is sorted by position to determine the equipment position sequence; Determine the equipment spacing between adjacent alkali adding equipment according to the equipment position sequence, and calculate the difference between the equipment spacing and the preset standard spacing to determine the difference spacing; According to the preset distance matching relationship, the excellent parameters corresponding to the difference distance are determined, and the average value of each excellent parameter is calculated to determine the preferred parameter; The preferred parameter with the largest value is determined according to the sorting rule, and the candidate device combination corresponding to the preferred parameter is defined as a valid device combination.

5. The waste incineration flue gas purification method based on the DCS system according to claim 4 is characterized in that: After the optimal parameter with the largest value is determined, the waste incineration flue gas purification method based on the DCS system also includes: Determine whether the optimal parameter with the largest value is greater than the preset reference parameter; If the preferred parameter with the largest value is greater than the reference parameter, the alternative equipment combination corresponding to the preferred parameter is defined as the effective equipment combination; If the preferred parameter with the largest value is not greater than the reference parameter, the available equipment combination corresponding to the overall suitable value is eliminated, and the available equipment combination with the largest overall suitable value is re-determined.

6. A waste incineration flue gas purification system based on a DCS system, characterized in that: include: An acquisition module is used to obtain the unit flow rate of the incineration flue gas and the unit flow rate of the characteristic gas at the entrance of the absorption tower; A processing module, connected to the acquisition module, for storing and processing information; The processing module calculates the characteristic flow ratio of each characteristic gas according to the characteristic gas unit flow rate and the incineration flue gas unit flow rate, wherein the characteristic gas is the acid gas with a larger content in the designated flue gas; The processing module combines the characteristic flow ratios to determine the gas distribution combination; The processing module establishes a detection interval with a width of a preset detection time length on a preset time axis with the current time point as the rear end point, and determines a similar distribution combination in the detection interval according to the gas distribution combination; The processing module determines the corresponding unit alkali addition amount according to each similar distribution combination in the detection interval, and calculates according to all the unit alkali addition amounts to determine the simulated alkali addition amount; The processing module controls the preset alkali adding equipment to add alkaline material into the absorption tower according to the simulated alkali adding amount; The step of determining a similar distribution combination according to the gas distribution combination in the detection interval by the processing module includes: The processing module defines the gas distribution combination determined in the detection interval as a historical distribution combination, and defines the characteristic flow ratio corresponding to the historical distribution combination as a historical flow ratio; The processing module calculates the flow similarity ratio in the same characteristic gas based on the historical flow ratio and the current characteristic flow ratio; The processing module determines similarity calculation parameters corresponding to the traffic similarity ratio according to the preset parameter matching relationship; The processing module performs a sum calculation based on all similarity calculation parameters to determine an overall similarity value, and defines a historical distribution combination whose overall similarity value is greater than a preset benchmark demand value as a similar distribution combination; The processing module calculates and determines the simulated alkali addition amount according to all the unit alkali addition amounts, and the steps include: The processing module determines the alkaline consumption corresponding to each characteristic gas according to a preset consumption matching relationship; The processing module calculates the characteristic consumption according to all historical flow ratios and the corresponding alkaline consumption, and calculates the difference between the unit alkali addition amount and the characteristic consumption to determine the excess consumption of the excess gas, wherein the excess gas is the acid gas other than the characteristic gas that can be treated by the alkaline material; The processing module calculates the theoretical consumption of the current excess gas according to the similar proportion of the flow of each characteristic gas and the excess consumption; The processing module performs mean calculation based on all theoretical consumptions determined in the same similar distribution combination to determine the theoretical excess mean; The processing module calculates the feasible excess average according to all theoretical excess averages to determine the feasible excess average, and calculates the simulated alkali addition amount according to the feasible excess average, the current characteristic flow ratio and the corresponding alkali consumption.

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