Construction And Application Of Evaluation Index System For Energy Conservation And Emission Reduction In Coal-Fired Power Plants

With the continuous development of the domestic economy,the demand for electricity is also increasing,and the number of power plants is also increasing.Thermal power plants have become the main source of power generation in China.According to statistics,thermal power generation accounts for more than half of the country’s electricity generation,in the process of thermal power generation,also accompanied by a large number of emissions of waste gas and pollutants.Coal-fired power plants account for about half of China’s total emissions of sulfur dioxide（SO₂）,while greenhouse gases such as nitrogen dioxide（CO₂）and nitrogen oxide（N_xO_x）also account for more than 30%of China’s total emissions.Therefore,it is an important task to realize the energy conservation and emission reduction and clean emission of thermal power plant.Before energy conservation and emission reduction of thermal power plants,it is necessary to find out the current situation of thermal power plants and their effect of energy conservation and emission reduction.Therefore,it is necessary to evaluate the energy conservation and emission reduction of thermal power plants.Based on this goal,this study analyzes the energy saving evaluation of thermal power plants and establishes a set of feasible energy saving evaluation index system of thermal power plants.First of all,based on the research and analysis of domestic and foreign literatures,the evaluation process and ideas for energy conservation and emission reduction of thermal power plants are determined,that is,selecting the thermal power plants to be evaluated,determining the evaluation objectives,and selecting the appropriate evaluation indexes.Based on the principles of comprehensiveness,scientificity and relevance,the framework of energy saving evaluation system for thermal power plants is established,and the index system is divided into four levels,namely target level,first level,second level and third level.Four evaluation indexes were selected and proofread.A questionnaire survey was conducted among 9 experts to select energy conservation evaluation indexes of thermal power plants,and 4 first-level indexes,23second-level indexes and 30 third-level indexes were obtained.After screening again,15second-level indicators and 20 third-level indicators were obtained,and the indicators were quantitatively analyzed.Secondly,AHP,gray relational degree,entropy weight and standard deviation coefficient are used to calculate the weight of each three-level index,and AHP is used to determine the weight of the middle-level index.The evaluation index model of energy conservation and emission reduction in thermal power plants is constructed,and the evaluation results are divided into five grades,which are excellent,good,medium,qualified and unqualified.Finally,taking a coal-fired power plant in Inner Mongolia as an example,through the investigation and analysis of its energy conservation and emission reduction status,energy conservation and emission reduction evaluation,the overall score of this coal-fired power plant is 84.219,which is rated as good.Among them,the resource and energy consumption index score 82.16 points,the grade is good.The environmental impact index score is 87.69,which is good.The comprehensive utilization index of resources scored 83.34,which was rated as good.The management index of energy conservation and emission reduction system scored 85.65 points,which was rated as good.The above results show that the evaluation model is scientific and practical,and provides a new tool and method for energy conservation and emission reduction of thermal power plants.