Variable Load Calculation And Sensitivity Analysis Of 1000MW Power Boiler

With the rapid development of Chinese economy,the annual electricity consumption and the proportion of new energy sources such as wind and solar energy of China has increased gradually,while the power generation structure has been continuously optimized at the same time.However,due to the discontinuous and volatility of new energy sources,their vigorous development,,has put forward higher requirements for the rapid peaking capacity of coal-fired units,which is the dominant force in the power generation market.And the proportion of large-capacity boilers in Chinese power station systems are raising.The rapid peaking means that the boilers should be developed to adapt to the rapid changes of the load,which indicates that higher requirements should be set on the operation regulation of large-capacity boilers.Above all,it is vital to study the variable working conditions of boilers,especially large-capacity boilers.This study takes a 1000 MW ultra-supercritical power station boiler as the research object.Firstly,the calculation model based on the boiler unit thermal calculation standard method and combined with the structural characteristics of the large-capacity power station boiler was constructed.Secondly,the model was used to carry out the 1000 MW boiler,and the variable working conditions was calculated.Then,the variation of heat exchange capacity of different heating surfaces of boiler under different working conditions,the change of main steam and reheat steam temperature of boiler were analyzed.After that,the problems that may exist in power plant boilers under low load were proposed.Meanwhile,the research uses the boiler model to analyze the influence of burner swing angle swing and tail flue gas baffle opening on boiler reheat steam and superheated steam.According to the results,when the boiler is operated under less than 50%BMCR,the boiler economizer outlet smoke temperature may be less than 300?,which is not conducive to the operation of the denitration system;while the burner swing angle swings upwards,the superheated steam temperature decreases.Also,when the temperature of the reheated steam increases,the fraction of the flue of the low temperature reheater will grow,and the temperature of the reheated steam will go up as well.But the temperature of the superheated steam decreases.This study can provide a reference for the heat calculation of large-capacity boilers and the economic,as well as the safety evaluation of boilers with low-load operation of large-capacity boilers.