Numerical Simulation Study on the Combustion Characteristics of Coal-Fired Boiler Under Different Loads

In pursuit of the strategic objectives of dual-carbon, China is hastening the restructuring and modernization of its energy sector. Within this context, coal-fired power units are transitioning from their conventional role as a primary electricity source to functioning as a supporting power supply, actively engaging in the grid’s profound peak regulation efforts. This empirical investigation focuses on a 660 MWe tangentially-fired boiler, employing numerical simulation techniques to develop a comprehensive three-dimensional model. The analysis primarily examines the attributes of combustion and the patterns of pollutant emission at operational capacities of 660 and 500 MWe. Combustion within the furnace demonstrated greater stability under full-load conditions, whereas a noticeable deflection of the flame occurred as the load diminished. Measured at the furnace outlet, NOx emissions were 168.76 and 347.16 mg/m3 for the 660 and 500 MWe loads, respectively. This substantial multiplicative rise in NOx concentration indicates that its relationship with boiler load is not simply linear. Consequently, implementing appropriate measures is essential under low-load conditions to effectively curb the formation of NOx.