An evaluation method and system for water-saving level of a thermal power plant based on analytic hierarchy process

Abstract

This invention provides a method and system for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process (AHP), relating to the field of water-saving technology in the power industry. Its key feature is the construction of an evaluation index system for the water-saving level of thermal power plants, comprising a target layer, a criterion layer, and an indicator layer; the target layer is the comprehensive evaluation value of the water-saving level of the thermal power plant. The advantages of this invention are: it constructs a comprehensive evaluation system covering four dimensions—water efficiency, recycling, technical equipment, and management level—overcoming the one-sidedness of traditional single-indicator or subjective experience-based evaluations; it scientifically determines the indicator weights using the AHP and ensures the reliability of the results through consistency checks, significantly improving the objectivity and comparability of the evaluation; the system not only outputs a comprehensive score and grade but also accurately identifies weak links in water-saving efforts and provides improvement suggestions, realizing the systematization, intelligence, and refinement of water-saving evaluation for thermal power plants.

Description

Technical Field

[0001] This invention relates to the field of water-saving technology in the power industry, and in particular to a method and system for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process. Background Technology

[0002] With increasingly scarce water resources and ever-increasing environmental protection requirements, the water-saving level of thermal power plants, as major water users in the industrial sector, directly affects the economic benefits of enterprises and the sustainable use of regional water resources. A scientific and rational assessment of the water-saving level of thermal power plants is of great significance for identifying weaknesses in water conservation, guiding water-saving renovations, and optimizing water use structure.

[0003] Currently, with the country's increasing emphasis on energy conservation, emission reduction, and green development, water conservation in thermal power plants is receiving growing attention. However, existing methods for assessing the water conservation level of thermal power plants generally have many shortcomings. On the one hand, most assessment systems rely on a single indicator (such as water consumption per unit of power generation) or are based on subjective experience, making it difficult to comprehensively and systematically reflect the overall water conservation capabilities of thermal power plants in terms of water management, equipment efficiency, recycling, and technological transformation. On the other hand, when constructing a multi-indicator evaluation system, the determination of indicator weights often relies on expert scoring or simple averaging, lacking scientific and rigorous mathematical support, resulting in highly subjective, incomparable, and difficult-to-promote assessment results.

[0004] Therefore, there is an urgent need for a water-saving level assessment method that can integrate multi-dimensional water-saving factors, has quantitative analysis capabilities, and has reasonable and reliable weight allocation, so as to improve the scientific and refined level of water-saving management in thermal power plants. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process (AHP). This invention solves the problems in existing methods for evaluating the water-saving level of thermal power plants, such as reliance on single indicators or subjective experience, incomplete evaluation, and lack of scientific mathematical support for determining weights in multi-indicator evaluation systems, which leads to strong subjectivity and poor comparability of evaluation results. This invention achieves a scientific, objective, and systematic evaluation of the water-saving level of thermal power plants.

[0006] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows:

[0007] A method and system for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process (AHP), characterized by comprising: S1: constructing an evaluation index system for the water-saving level of thermal power plants, wherein the index system includes a target layer, a criterion layer, and an index layer;

[0008] The target layer is the comprehensive evaluation value of the water-saving level of thermal power plants;

[0009] The criteria layer includes four core dimensions: water use efficiency, recycling level, technological equipment level, and water management level; the indicator layer includes several quantitative and / or qualitative water-saving indicators belonging to the dimensions of each criteria layer.

[0010] S2: Construct judgment matrices for each level based on the analytic hierarchy process, use the 1-9 scale method to quantify the relative importance of each factor at the same level relative to a factor at the next higher level, and determine the judgment matrices of the criteria layer relative to the target layer and the indicator layer relative to the dimensions of its respective criteria layer through expert scoring.

[0011] S3: Perform a consistency check on each judgment matrix. If the check passes, calculate the comprehensive weight of each water-saving index relative to the target layer based on each judgment matrix. If the check fails, correct the judgment matrix until the consistency check is passed.

[0012] S4: Collect the raw data of each water-saving index of the thermal power plant to be evaluated, and perform dimensionless processing on the raw data to obtain the score value of each water-saving index.

[0013] S5: Based on the comprehensive weight and the score values ​​of each water-saving index, the comprehensive evaluation value of the water-saving level of the thermal power plant to be evaluated is calculated by weighting, and the evaluation level, the sub-item score of each criterion layer and the single item score of each index layer are output according to the preset water-saving level classification standard to identify weak links in water saving.

[0014] As an improvement, the indicator layer of the water efficiency dimension includes water intake per unit of power generation, water consumption per unit of power generation, and reuse rate.

[0015] The indicators for the level of recycling include the circulating cooling water concentration ratio, ash and slag system reuse rate, domestic sewage reuse rate, and condensate recovery rate.

[0016] The indicators for the technical equipment level include the application rate of air-cooled systems, the popularization rate of high-efficiency water-saving equipment, the online monitoring coverage rate, and the application level of dry cooling technology.

[0017] The indicators for the water management level dimension include water quota execution rate, water conservation management system completeness, water conservation training coverage rate, and frequency of water balance testing.

[0018] As an improvement, the specific method for calculating the comprehensive weight in step S3 is as follows: First, calculate the maximum eigenvalue of each judgment matrix. and its corresponding eigenvectors;

[0019] Secondly, the feature vectors are normalized to obtain the local weights of each factor relative to its previous level factor.

[0020] Finally, the local weights of each indicator in the indicator layer are multiplied by the corresponding local weights in the criterion layer to obtain the comprehensive weights of each water-saving indicator relative to the target layer.

[0021] As an improvement, the specific method for consistency verification in step S3 is as follows: calculate the consistency index. ,in To determine the order of a matrix;

[0022] according to Find the average random consistency index ;

[0023] Calculate the consistency ratio ;when When <0.1, the judgment matrix passes the consistency test;

[0024] Otherwise, it will be considered a failure.

[0025] As an improvement, step S4 involves dimensionless processing of the original data, specifically including: for positive indices, using the formula... or Process it;

[0026] For negative indicators, the formula is used. or Process it;

[0027] in, The original data, The score is the dimensionless score. and These are the reference maximum and minimum values ​​for this indicator, respectively. This refers to the industry benchmark or standard limit for this indicator.

[0028] As an improvement, the water-saving level classification standard in step S5 includes: dividing the numerical range of the comprehensive evaluation value of water-saving level into five levels: "excellent", "good", "medium", "poor" and "very poor", each corresponding to a different comprehensive evaluation value range.

[0029] As an improvement, step S6 is also included: based on the identified weak links in water conservation, and combined with the weight and score of each indicator, targeted water conservation improvement suggestions are generated.

[0030] A system for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process (AHP), characterized in that it is used to implement the evaluation method as described in any one of claims 1 to 7, the system comprising:

[0031] Indicator system construction module: Used to store and manage the indicator system for evaluating the water-saving level of thermal power plants, allowing users to add, delete or modify indicators;

[0032] Weight calculation module: used to construct a judgment matrix based on the analytic hierarchy process, perform consistency checks, and calculate the comprehensive weight of each water-saving index;

[0033] Data acquisition and processing module: used to collect raw data of various water-saving indicators of the thermal power plant to be evaluated, and to perform dimensionless processing on the raw data to obtain the score value of each water-saving indicator.

[0034] Assessment Calculation and Output Module: Used to calculate the comprehensive assessment value of water-saving level with weights, and output the assessment level, assessment report and information on weak links in water saving.

[0035] As an improvement, the system also includes an expert scoring management module and a data interface module;

[0036] The expert scoring management module is used to input, store and manage the scoring data of multiple experts, and supports weighted average or geometric average processing of the scoring results of multiple experts to generate a comprehensive judgment matrix.

[0037] The data interface module is used to interface with the production management system and water metering system of thermal power plants to realize automatic collection, periodic updating and abnormal data early warning of assessment data.

[0038] As an improvement, the system also includes a historical trend analysis module and a scheme comparison module;

[0039] The historical trend analysis module is used to store relevant data of the same thermal power plant at different points in time, generate trend charts of changes in indicators and comprehensive evaluation values, and evaluate the effect of water-saving renovation.

[0040] The scheme layer comparison module is used to calculate the comprehensive evaluation value of multiple thermal power plants under the same indicator system, and output the ranking results and comparative analysis report.

[0041] The beneficial effects of this invention are: it overcomes the shortcomings of existing technologies that rely on a single indicator (such as water consumption per unit of power generation) or subjective experience. By constructing a comprehensive indicator system that includes four dimensions—"water use efficiency, recycling level, technical equipment level, and water management level"—it can comprehensively and systematically reflect the overall water-saving capacity of thermal power plants in various aspects.

[0042] This invention enhances the scientific rigor and objectivity of the evaluation: Addressing the challenge of determining weights in multi-indicator evaluation systems, this invention employs the Analytic Hierarchy Process (AHP), a scientific mathematical method, to determine the weights of each indicator. Through steps such as constructing a judgment matrix and conducting consistency checks, the rationality and reliability of the weight allocation are ensured, thereby significantly reducing the subjectivity of the evaluation results.

[0043] The system enhances the comparability and practicality of the assessment results: Due to the adoption of standardized assessment methods and scientific weighting calculations, the water-saving assessment results among different thermal power plants are highly comparable. Furthermore, the system not only outputs a comprehensive assessment value and grade but also provides scores for each sub-item, accurately identifying weaknesses in water-saving efforts and providing clear direction for subsequent water-saving renovations.

[0044] The system has achieved a systematic and intelligent assessment: the supporting assessment system integrates functions such as indicator management, weight calculation, data collection, assessment output, historical trend analysis, and multi-plant comparison. This not only improves the efficiency of the assessment work, but also supports dynamic tracking and horizontal comparison of the effects of water-saving renovations, thereby enhancing the scientific and refined level of water-saving management in thermal power plants. Attached Figure Description

[0045] Figure 1 This is a flowchart of a method for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process (AHP) of the present invention.

[0046] Figure 2 This is a block diagram of the overall architecture of a water-saving level assessment system for thermal power plants based on the analytic hierarchy process (AHP) of the present invention. Detailed Implementation

[0047] To make the content of this invention easier to understand, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Identical components are represented by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to directions in the accompanying drawings, while the terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0048] like Figure 1 As shown, a method and system for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process (AHP) is characterized by the following steps: S1: Constructing an evaluation index system for the water-saving level of thermal power plants, the index system includes a target layer, a criterion layer, and an indicator layer; the target layer is the comprehensive evaluation value of the water-saving level of the thermal power plant; the criterion layer includes four core dimensions: water use efficiency, recycling level, technical equipment level, and water management level; the indicator layer includes several quantitative and / or qualitative water-saving indicators belonging to the dimensions of each criterion layer; S2: Constructing a judgment matrix for each level based on the AHP, using the 1-9 scale method to quantify the relative importance of each factor at the same level relative to a factor at the next higher level, and determining the judgment matrix of the criterion layer relative to the target layer and the indicator layer relative to its respective criterion layer dimension through expert scoring;

[0049] S3: Perform a consistency check on each judgment matrix. If the check passes, calculate the comprehensive weight of each water-saving index relative to the target layer based on each judgment matrix. If the check fails, revise the judgment matrix until the consistency check is passed. S4: Collect the original data of each water-saving index of the thermal power plant to be evaluated, and perform dimensionless processing on the original data to obtain the score value of each water-saving index. S5: Calculate the comprehensive evaluation value of the water-saving level of the thermal power plant to be evaluated based on the comprehensive weight and the score value of each water-saving index. Output the evaluation level, the sub-item score of each criterion layer and the single item score of each index layer according to the preset water-saving level classification standard to identify weak links in water saving.

[0050] The indicators for water efficiency include water intake per unit of power generation, water consumption per unit of power generation, and reuse rate; the indicators for recycling level include circulating cooling water concentration ratio, ash and slag system reuse rate, domestic sewage reuse rate, and condensate recovery rate; the indicators for technology and equipment level include air cooling system application rate, high-efficiency water-saving equipment popularization rate, online monitoring coverage rate, and dry cooling technology application level; and the indicators for water management level include water quota execution rate, water-saving management system completeness, water-saving training coverage rate, and frequency of water balance testing.

[0051] The specific method for calculating the comprehensive weight in step S3 is as follows: First, calculate the maximum eigenvalue of each judgment matrix. First, the eigenvectors are normalized to obtain the local weights of each factor relative to its previous level factor. Second, the local weights of each indicator in the indicator layer are multiplied by the corresponding local weights in the criterion layer to obtain the comprehensive weights of each water-saving indicator relative to the target layer.

[0052] The specific method for consistency verification in step S3 is as follows: calculate the consistency index. ,in To determine the order of a matrix; according to Find the average random consistency index ; Calculate the consistency ratio ;when If the value is less than 0.1, the judgment matrix is ​​considered to have passed the consistency test; otherwise, it is considered to have failed.

[0053] Step S4 involves dimensionless processing of the raw data, specifically including: for positive indicators, using the formula... or Process accordingly; for negative indicators, use the formula. or Process it;

[0054] in, The original data, The score is the dimensionless score. and These are the reference maximum and minimum values ​​for this indicator, respectively. This refers to the industry benchmark or standard limit for this indicator.

[0055] The water-saving level classification standard in step S5 includes: dividing the numerical range of the comprehensive evaluation value of water-saving level into five levels: "excellent", "good", "medium", "poor" and "very poor", each corresponding to a different comprehensive evaluation value range.

[0056] It also includes step S6: Based on the identified weak links in water conservation, and combined with the weight and scoring of each indicator, generate targeted water conservation improvement suggestions.

[0057] like Figure 2 As shown, a water-saving level assessment system for thermal power plants based on the analytic hierarchy process (AHP) is characterized by the following features: A system for constructing an indicator system: used to store and manage the water-saving level assessment indicator system for thermal power plants, allowing users to add, delete, or modify indicators; a weight calculation module: used to construct a judgment matrix based on the AHP, perform consistency checks, and calculate the comprehensive weight of each water-saving indicator; a data acquisition and processing module: used to collect the raw data of each water-saving indicator of the thermal power plant to be assessed, and perform dimensionless processing on the raw data to obtain the score value of each water-saving indicator; and an assessment calculation and output module: used to calculate the comprehensive assessment value of the water-saving level using weighted calculation, and output the assessment level, assessment report, and information indicating weak points in water-saving efforts.

[0058] The system also includes an expert scoring management module and a data interface module. The expert scoring management module is used to input, store and manage the scoring data of multiple experts, and supports weighted average or geometric average processing of the scoring results of multiple experts to generate a comprehensive judgment matrix. The data interface module is used to interface with the production management system and water metering system of thermal power plants to realize automatic collection, periodic updating and abnormal data early warning of evaluation data.

[0059] The system also includes a historical trend analysis module and a scheme comparison module. The historical trend analysis module is used to store relevant data of the same thermal power plant at different time points, generate trend charts of changes in indicators and comprehensive evaluation values, and evaluate the effect of water-saving renovation. The scheme comparison module is used to calculate the comprehensive evaluation values ​​of multiple thermal power plants under the same indicator system, and output the ranking results and comparative analysis reports.

[0060] In the implementation process, the first step is to construct an evaluation index system for the water-saving level of thermal power plants. This system includes three levels: the target level (comprehensive evaluation value of the water-saving level of thermal power plants), the criteria level (four dimensions: water use efficiency, recycling level, technical equipment level, and water management level), and the indicator level (specific indicators under each dimension). Then, judgment matrices for each level are constructed based on the analytic hierarchy process (AHP). Using the 1-9 scaling method, expert scoring is used to determine the judgment matrices for the criteria level relative to the target level, and for the indicator level relative to its respective criterion level dimension. Next, a consistency test is performed on each judgment matrix. When the consistency ratio CR < 0.1, the judgment matrix passes the consistency test, and the comprehensive weight of each water-saving indicator can be calculated accordingly; otherwise, the judgment matrix needs to be revised until it passes the consistency test.

[0061] Subsequently, raw data on various water-saving indicators of the thermal power plant to be evaluated were collected and dimensionless. For positive indicators (the higher the value, the better), the corresponding positive processing formula was used; for negative indicators (the lower the value, the better), the corresponding negative processing formula was used to obtain the score value of each water-saving indicator. Finally, based on the comprehensive weight and the score values ​​of each water-saving indicator, a weighted calculation was performed to obtain the comprehensive evaluation value of the water-saving level of the thermal power plant to be evaluated. The evaluation results were output according to the preset water-saving level classification standard, including the evaluation level, the scores of each criterion level, and the individual scores of each indicator level, thereby identifying the weak links in water-saving.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process (AHP), characterized in that, Includes the following steps: S1: Construct an evaluation index system for the water-saving level of thermal power plants, the index system including target layer, criterion layer and index layer; The target layer is the comprehensive evaluation value of the water-saving level of thermal power plants; The criteria layer includes four core dimensions: water use efficiency, recycling level, technological equipment level, and water management level; the indicator layer includes several quantitative and / or qualitative water-saving indicators belonging to the dimensions of each criteria layer. S2: Construct judgment matrices for each level based on the analytic hierarchy process, use the 1-9 scale method to quantify the relative importance of each factor at the same level relative to a factor at the next higher level, and determine the judgment matrices of the criteria layer relative to the target layer and the indicator layer relative to the dimensions of its respective criteria layer through expert scoring. S3: Perform a consistency check on each judgment matrix. If the check passes, calculate the comprehensive weight of each water-saving index relative to the target layer based on each judgment matrix. If the test fails, the judgment matrix is ​​modified until the consistency test is passed; S4: Collect the raw data of each water-saving index of the thermal power plant to be evaluated, and perform dimensionless processing on the raw data to obtain the score value of each water-saving index. S5: Based on the comprehensive weight and the score values ​​of each water-saving index, the comprehensive evaluation value of the water-saving level of the thermal power plant to be evaluated is calculated by weighting, and the evaluation level, the sub-item score of each criterion layer and the single item score of each index layer are output according to the preset water-saving level classification standard to identify weak links in water saving.

2. The method for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process according to claim 1, characterized in that, The indicators for water efficiency include water intake per unit of electricity generation, water consumption per unit of electricity generation, and reuse rate. The indicators for the level of recycling include the circulating cooling water concentration ratio, ash and slag system reuse rate, domestic sewage reuse rate, and condensate recovery rate. The indicators for the technical equipment level include the application rate of air-cooled systems, the popularization rate of high-efficiency water-saving equipment, the online monitoring coverage rate, and the application level of dry cooling technology. The indicators for the water management level dimension include water quota execution rate, water conservation management system completeness, water conservation training coverage rate, and frequency of water balance testing.

3. The method for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process according to claim 2, characterized in that, The specific method for calculating the comprehensive weight in step S3 is as follows: First, calculate the maximum eigenvalue of each judgment matrix. and its corresponding eigenvectors; Secondly, the feature vectors are normalized to obtain the local weights of each factor relative to its previous level factor. Finally, the local weights of each indicator in the indicator layer are multiplied by the corresponding local weights in the criterion layer to obtain the comprehensive weights of each water-saving indicator relative to the target layer.

4. The method for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process according to claim 3, characterized in that, The specific method for consistency verification in step S3 is as follows: Calculate the consistency index. ,in To determine the order of a matrix; according to Find the average random consistency index ; Calculate the consistency ratio ;when When <0.1, the judgment matrix passes the consistency test; Otherwise, it will be considered a failure.

5. The method for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process according to claim 4, characterized in that, Step S4 involves dimensionless processing of the original data, specifically including: for positive indices, using the formula... or Process it; For negative indicators, the formula is used. or Process it; in, The original data, The score is the dimensionless score. and These are the reference maximum and minimum values ​​for this indicator, respectively. This refers to the industry benchmark or standard limit for this indicator.

6. The method for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process according to claim 5, characterized in that, The water-saving level classification standard in step S5 includes: dividing the numerical range of the comprehensive evaluation value of water-saving level into five levels: "excellent", "good", "medium", "poor" and "very poor", each corresponding to a different comprehensive evaluation value range.

7. The method for evaluating the water-saving level of thermal power plants based on the analytic hierarchy process according to claim 6, characterized in that, It also includes step S6: Based on the identified weak links in water conservation, and combined with the weight and scoring of each indicator, generate targeted water conservation improvement suggestions.

8. A water-saving level assessment system for thermal power plants based on the analytic hierarchy process (AHP), characterized in that, The system for implementing the evaluation method as described in any one of claims 1 to 7 comprises: Indicator system construction module: Used to store and manage the indicator system for evaluating the water-saving level of thermal power plants, allowing users to add, delete or modify indicators; Weight calculation module: used to construct a judgment matrix based on the analytic hierarchy process, perform consistency checks, and calculate the comprehensive weight of each water-saving index; Data acquisition and processing module: used to collect raw data of various water-saving indicators of the thermal power plant to be evaluated, and to perform dimensionless processing on the raw data to obtain the score value of each water-saving indicator. Assessment Calculation and Output Module: Used to calculate the comprehensive assessment value of water-saving level with weights, and output the assessment level, assessment report and information on weak links in water saving.

9. A water-saving level assessment system for thermal power plants based on the analytic hierarchy process according to claim 8, characterized in that, The system also includes an expert scoring management module and a data interface module; The expert scoring management module is used to input, store and manage the scoring data of multiple experts, and supports weighted average or geometric average processing of the scoring results of multiple experts to generate a comprehensive judgment matrix. The data interface module is used to interface with the production management system and water metering system of thermal power plants to realize automatic collection, periodic updating and abnormal data early warning of assessment data.

10. A water-saving level assessment system for thermal power plants based on the analytic hierarchy process according to claim 9, characterized in that, The system also includes a historical trend analysis module and a scheme comparison module; The historical trend analysis module is used to store relevant data of the same thermal power plant at different points in time, generate trend charts of changes in indicators and comprehensive evaluation values, and evaluate the effect of water-saving renovation. The scheme layer comparison module is used to calculate the comprehensive evaluation value of multiple thermal power plants under the same indicator system, and output the ranking results and comparative analysis report.

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