Research On Safety And Economic Performance Of Rotary Air Preheater Based On Operation Big Data Analysis

With the introduction of "double carbon" policy and energy structure adjustment,the traditional thermal power generation method can no longer meet the current "low carbon" and"intelligent" development goals,and needs to make adjustments and changes.change.As an indispensable flue gas heat exchange equipment in the tail flue of boilers,the reliability index of rotary air preheater can be monitored to identify and warn the operation status of rotary air preheater and reduce the possibility of failure during the operation of rotary air preheater,which can help the safety and stability of the whole thermal power unit.This thesis takes the rotary air preheater of a 300 MW coal-fired power plant boiler tail flue heat exchanger as the research object,and applies the big data technology to the rotary air preheater.Firstly,the target indexes of each problem and the indexes of the influencing factors were established starting from the problems(high air leakage rate,low temperature corrosion and ammonium hydrogen sulfate condensation and ash accumulation)that often occur during the operation of rotary air preheater.By Pearson correlation coefficient method based on historical operation data,the correlation between the target index of each problem and the main influencing factors is analyzed,and the influencing factors with large correlation are analyzed based on XGBoost algorithm for component weighting to get the degree size of influencing each problem,and the results show that among the main factors affecting the air leakage of rotary air preheater,the influence of unit load is the largest,accounting for 64.95%;among the main factors affecting the low-temperature corrosion and ash accumulation of rotary air preheater,the influence of flue gas outlet temperature is the largest,accounting for 38.30%;among the main factors affecting ammonium bisulfate condensation and ash accumulation in the rotary air preheater,the influence of ammonia fugitive concentration is the largest,accounting for 78.31%.Secondly,the factor that affects the greatest degree of each problem of rotary air preheater is used as the basis for work condition division,and the target index of each problem is used as the reliability index of each problem.Based on the discrete degree analysis method,the discrete degree of reliability indexes in each operating condition interval is analyzed and the probability of abnormality of reliability indexes in each operating condition interval is quantitatively calculated,which provides theoretical guidance for future monitoring of rotary air preheater reliability indexes to identify the operational status of rotary air preheaters,early warning and correction of deviations.Finally,through the big data analysis platform,based on the historical operation data,the change law of heat transfer coefficient of rotary air preheater was regressed,and based on the working principle and heat transfer process of rotary air preheater,the heat transfer program was written based on MATLAB software using finite difference method and the temperature field of metal heat storage plate of rotary air preheater was simulated based on the change law of heat transfer coefficient of rotary air preheater,which provided the theoretical basis for determining the low temperature corrosion and ammonium hydrogen sulfate condensation region provides a theoretical basis;In addition,based on the EBSILON software,a threecompartment rotary air preheater assembly was developed and a 300 MW coal-fired power plant boiler and turbine thermal coupling system was built to simulate and analyze the effect of the rotary air preheater on the economic performance of thermal power units when the average value of heat transfer coefficient and the upper limit,average value and lower limit of reliability index are obtained under different unit loads.According to this law,the operation of the unit can be optimized,and the economic performance and energy utilization of the unit can be improved.This thesis uses big data technology,MATLAB and EBSILON software to analyze the safety and economy of rotary air preheater operation process,which can provide theoretical guidance for identifying rotary air preheater operation status,early warning,correction of deviation and optimizing unit operation.