Numerical Simulation Study On Low Nitrogen Combustion Characteristics Of Chain Boiler

With the deepening of China's urban industrialization process,China's demand for distributed energy reserves increased year by year.Coal-fired industrial boilers with its low cost,wide range of advantages,the use of year by year.However,the environmental problems caused by coal burning,increasingly affecting people's daily life,and on the current energy structure of China's point of view,for a long period of time,coal is still China's main energy form,so control the living environment Within the pollutant emissions is essential.Chain furnace is one of the most widely used furnaces in coal-fired industrial boilers.As the process and mechanism of combustion are complicated,the influencing factors have not been clearly stated.Therefore,the generation rules and emptying of nitrogen oxides in chain furnace Measures are worth exploring in depth.In this paper,a 14 MW hot water chain boiler is used as the simulation object by using GAMBIT pretreatment software.The geometric structure of the simulated object is simplified and the boundary condition of the simplified physical model is set reasonably.Simulation study pre-processing work.In this paper,FLUENT simulation software,through the chain furnace combustion process and nitrogen oxide production process simulation,to explore the distribution mode,furnace structure parameters,the way the exhaust air arrangement of the furnace furnace combustion characteristics and nitrogen oxides The impact of the process.Firstly,in the process of numerical simulation,compared with the simulation data formation under different grid precision,after the analysis of the grid independent analysis,the simulation results and the normal operation data of the boiler are used,and the same type of boiler And the rationality of the mathematical model,combustion model,flow model,physical model and boundary condition selected in the numerical simulation process are verified by comparing the data produced by numerical simulation.Secondly,by changing the structure of the furnace arch to explore the impact of structural parameters;by regulating the lower part of the furnace at the entrance of the air intake of each wind chamber to adjust the proportion of air distribution mode;by changing the structure of the way the wind,The amount of wind to explore the impact of the way the exhaust air layout.Finally,the above analysis summarizes the above data,analyzes the law of data generation,and draws the following conclusions: FLUENT simulation software can simulate the combustion process and nitrogen oxide production process in chain furnace.The combustion of the various sections of the change,affecting the volatile N and coke N formation and transformation process,which delayed the wind with a significant reduction in nitrogen oxide emissions;furnace structure changes affect the furnace high temperature flue gas The mixing of the flow and the flue gas in the arch area affects the ignition and burning of the fuel,thereby affecting the final emissions of the nitrogen oxides;the manner in which the air is exhausted,the air temperature and the amount of air to the fuel burn and nitrogen The discharge of the object will have varying degrees of influence.