某300 MW机组对冲燃烧锅炉低氮燃烧改造中采用AireJet和DRB-4Z燃烧器，并加装了双风区OFA（燃尽风）喷口。经试验调整， OFA风箱挡板开度在50％～100％区间时对降低NOX的排放值有很好的效果。 OFA喷口二次风套筒、中心风挡板开度全开，外二次风叶片角度关小，尽量关小备用燃烧器层的风箱挡板开度，有利于降低NOX排放。在锅炉运行配风方面， OFA风箱挡板50％～100％， Aire-Jet燃烧器层风门开度35％， DRB-4Z燃烧器层风门开度在45％～55％区间，可获得降低NOX的最优效果。在300 MW工况下，省煤器出口NOX排放值由改造前的500～700 mg/m3降低至280 mg/m3以下。%The low NOX AireJet, DAR-4Z burners are used and OFA nozzles in dual air zone are installed in low NOX retrofit of opposed firing boilers of 300 MW units. Through test and adjustment , when OFA box damper opening is between 50% and 100%, the NOX emission can be reduced. To fully open the secondary air bushing at OFA nozzle, damper of the central air, reduce the angle of the external secondary air blade and box damper opening of standby burner can decrease NOX emission. For the air distribution for boiler op-eration, when the air box damper opens by 50% to 100%, the ventilation door of AireJet burner opens by 35%and that of DRB-4Z burner opens by 45%to 55%, the NOX emission is optimal. In case of 300 MW op-erating condition, NOX emission at economizer outlet decreases from 500~700 mg/m3 before the retrofit to 280 mg/m3 or the below.
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