Research On Low NO_x Combustion Retrofit Of 330MW Generating Unit In Xuanhua Thermal Power Plant

In order to reduce the emission of NO_X of 2×330MW generation unit of Hebei Xuanhua thermal power plant,the boiler burner are retrofitted by new low NO_X combustion burners and boiler performance as well as the modification effect of the total unit are investigated.First of all,this paper lists literature to explain the research status of low nitrogen combustion technology and technology at home and abroad.The generation principle of NO_X is briefly introduced,and the NO_X control technology in coal fired power plant is analyzed by the principle analysis.The advantages and disadvantages of air staged combustion,fuel staged combustion,flue gas recirculation,low NO_X burner and other low NO_X combustion technologies are analyzed.Then the combustion process of Xuanhua thermoelectric 330 MW subcritical boiler are studied,as well as the influence factors on the combustion and emission of NO_X.The optimal measures for reducing NO_X emission are put forward.Thermal debugging e Xperiment of Xuanhua power 330 MW boiler is carried out,then the optimal operation mode of reducing NO_X emissions is obtained.Finnally,guidance for the operation of power plant staff is proposed.The results show that coal quality,mill operation mode and running oxygen have important influence on SCR nitrogen inlet concentration.With the use of advanced low-NO_X burner,coal combustion efficiency is improved in the case of low-excess air coefficient,and adaptability of coal is enhanced.In the process of coal fluctuations,furnace conditions can be effectively stable.The combustion experiment was carried out under different working conditions of high,middle and low load sections.The results show that the SCR inlet nitrogen oxide concentration of ABDE grinding operation is increased at low load,but the CO concentration and fly ash is lower,and the boiler thermal efficiency is increased;At the high load,the nitrogen oxide concentration of the SCR inlet is decrea sed obviously,but the thermal efficiency of the boiler is also decreased obviously.In normal operation,the appropriate reduction of oxygen have assistance to reduce the concentration of nitrogen oxides at the entrance.