Numerical Simulation Optimization On Low Nitrogen Combustion-SCR Denitration Simulation Experiment Of Panshan Power Plant 600MW Coal-fired Boiler

Coal is the most abundant fossil energy resource in the world,and also it is a very important means of production and basic energy of our country.However,burning coal has a great harm to the atmospheric environment,and nitrogen is one of the common air pollutants.Nitrogen including NO?NO₂?N₂O?N₂O₅,impact ecological environment through the formation of acid rain and destruction of the ozone layer,induce emphysema such as asthma and respiratory diseases.It also generates secondary pollution to the environment and threaten human health by photochemical reaction.Coal-fired plants have advantages of short construction cycle,mature technology,strong grid peak shaving capacity and wide fuel sources,which will still account for more than 60% of the total installed capacity in a long time.High parameters,low energy consumption and zero emissions is the developing direction of the future coal-fired plants.Tangentially fired is the most widely used combustion mode in large units.As the public opinion's emphasis on environmental protection,the improvement of government standard and the strict implementation of a series of rewards and punishment policy,research on how to reduce NO_x emissions in tangentially fired boiler has important significance for plant's safety and economy.This article takes a 600 MW boiler of Tianjin Datang Panshan Power Plant as research background,which has already implemented low-nitrogencombustion + SCR transformation.Analyzes the effects of low-nitrogen combustion and SCR for boiler's safety and economy separately,and put forward the concept of the best SCR's entrance NO_x concentration.Firstly,it introduces numerical simulation's basic ideas,selects the appropriate calculation model,establish three-dimensional model and divide the grid of the boiler by the software named ICEMCFD.At last it search for the optimal operating conditions by FLUENT simulation calculation.The 4th chapter explains the boiler'scombustion process impact of changing SOFA's swing angle.It sets 4 conditions respectively,which contains non-SOFA,SOFA's air ratio 50% and swing angle flat 0°,SOFA's air ratio 50% and swing angle 20°upward,SOFA's air ratio 50% and swing angle 20° downward.This chapter also simulates every condition's distribution of temperature,velocity,CO,O₂ and NO_x,in order to compare the results between SOFA and non-SOFA,and search for the best SOFA swing angle.The 5th chapter studies the boiler's combustion process impact of different mills combination with SOFA.According to common practical combination,it sets 3 conditions which contains ABCDE coal mills,ABCDF coal mills,BCDEF coal mills,all of them with SOFA's air ratio 50% and swing angle flat 0°,in order to simulates every condition's distribution of temperature,velocity,CO,O₂ and NO_x.At last,there will be a thermal state combustion adjustment experiment by entrance boundary conditions,and the experiment results agree with the simulation.Considering the results of simulation and experiment,we can confirm the best SOFA swing angle and mills combination.The conclusions afford a valuable reference for the selections of SOFA+SCR transformation in the same kind boiler,while pointing the right directions for operating staff 's combustion adjustment work.