Research On Influence Factors Of Multi-pollutan Removal Capacity In Coal-fired Power Plant

At present,the common air pollutants in the environment contain SO2,NOx,dust,heavy metals and so on.Among all the fixed sources of these pollutants,the proportion of coal-fired power plants is the highest.In recent years,the Chinese government has promulgated the latest and so far the most stringent "thermal power plant air pollutant discharge standards."The process of air pollutant removal in coal-fired power plants mainly includes desulfurization process,denitrification process and dust removal process.At present,the most commonly used air pollutant removal system for coal-fired power plants is composed of SCR,electrostatic precipitator and wet flue gas desulfurization system.This air pollutant control system can be very effective control of power plant SO2,NOx,dust particles emissions.Theoretical and experimental studies have shown that there are many factors that affect the efficiency of SCR denitrification,dust removal and desulfurization of desulphurization tower.Among them,the flue gas temperature and flue gas flow rate are the factors that can affect the denitration efficiency of the SCR system,the efficiency of the electrostatic precipitator dust removal and the desulfurization efficiency of the wet flue gas desulfurization system.They are called the common factors that affect the removal of air pollutants in the power plant Influencing factors,and the parameters corresponding to the common influencing factors are called common parameters.The experimental results show that the removal efficiency of SCR system,ESP system and wet flue gas desulfurization system will be different when the flue gas temperature and the average flue gas flow rate of the inlet pollutant removal system of the power plant change And varying degrees of change.This phenomenon shows that the power plant can change the exhaust gas temperature and the average flue gas flow rate through the inlet of the air pollutant removal system to adjust the removal efficiency of S02,NOx and dust in the power plant,so as to improve the atmospheric pollutant In addition to capacity.In this paper,the research on the air pollutant control system of thermal power plant is carried out.By monitoring the relevant data of a 600MW coal-fired generating set in Inner Mongolia,the denitrification efficiency of SCR system,the efficiency of dust removal,The desulfurization efficiency of the system and the temperature and average velocity of the flow through their flue gas.According to the study,it is found that the comprehensive removal ability of the three major air pollutants in the power plant can be judged by the cost of environmental damage caused by air pollutant discharge.According to the measured data provided by the power plant and the environmental cost estimation method of air pollutants,we obtained the numerical relationship between the main air pollutant removal efficiency and the environmental loss cost caused by the unexplored part.Based on the above research results,this paper establishes the evaluation model of the comprehensive removal ability of pollutants in the whole air pollutant removal system with the removal efficiency of the three major air pollutant removal processes in the power plant,and obtains the SCR inlet smoke Gas temperature,average flue gas flow rate and the whole air pollutant removal system of pollutants in the comprehensive removal of the relationship between the ability.The corresponding energy loss cost is calculated by comparing the flue gas flow rate and the flue gas temperature and the corresponding air pollutant removal efficiency measured by the power plant into the comprehensive evaluation model of the air pollutant comprehensive removal capacity of the power plant,and the air pollution The relationship between the flue gas temperature,the average flue gas flow rate and the comprehensive removal capacity of the air pollutant in the power plant is obtained.Through the method of satisfying the maximum value of the objective function under the constraint condition,we can get the inlet flue gas temperature and the average flue gas flow rate corresponding to the optimal removal ability of pollutant in the air pollutant control system.