| With the rapid development of the economy and the increasing population,the amount of electricity consumption is also increasing rapidly.The amount of coal burned in the thermal power industry is also increasing,and the impact of atmospheric pollution from thermal power plants is becoming more and more significant.Nitrogen oxide(NOx)has become one of the major atmospheric pollutants emitted by coal-fired power plants.How to effectively improve the boiler efficiency while reducing NOx emissions has become an urgent problem that coal-fired power plants need to solve.In order to improve the combustion efficiency of the boiler,reduce the emission of pollutants,ensure safety and reliability,and achieve greater economic benefits,we should strengthen research on these aspects.The main work of this article is to analyze and study the control characteristics of combustion optimization parameters and temperature field distribution in the 600 k W coal-fired boiler experimental platform.We used Gambit software to establish a three-dimensional grid model of the experimental platform and conducted numerical simulation research using Fluent software.Finally,through the research of control strategies for the experimental furnace using Matlab,we studied the NOx emissions and temperature control during stable combustion inside the furnace,providing an effective control strategy for stable operation of the on-site device.The main research contents are as follows:First,we consulted relevant reference literature,analyzed the mathematical models used in the numerical simulation calculation stage according to the basic idea of numerical simulation,determined the mathematical control equations needed to establish the research equipment model,established a mathematical model of the600 k W experimental platform,in addition,a grid model of the experimental platform was established,with boundary conditions set,and the accuracy of the model was verified using Fluent software.Second,through theoretical analysis of the thermal simulation data using Fluent software,with the aim of improving combustion efficiency and reducing pollutant emissions,we optimized the structural parameters of the 600 k W experimental platform.We determined the optimal position of the secondary air nozzle,the secondary air flow rate,and the swirl plate angle of the system.On this basis,we also discussed the characteristics of the burn-out zone and reduction zone,selected the optimal position of the burn-out zone nozzle,and determined the gas-phase concentration that achieves the best reduction effect on NOx in the reduction zone.Finally,based on the Fluent simulation results,we predicted the temperature field distribution inside the furnace,the generation of various gas component substances and NOx,and determined the optimal operating conditions that meet the requirements for the NOx emission at the end of the experimental furnace.We connected the designed controller to the simulation model of the control system in the Simulink software package and used Matlab software to simulate the temperature control system of the entire experimental platform.Combining numerical simulation and control algorithms,we conducted research on combustion optimization and low NOx emission control problems,proposed optimization strategies and methods for experimental furnace operation,and achieved ultra-low NOx emissions from the experimental furnace. |
