Air distribution method and system reducing NOX emission and relieving coking

The invention relates to the field of large coal-fired power plant boilers, in particular to an air distribution method and system reducing NOX emission and relieving coking. To overcome the defects that air distribution of existing domestic coal-fired power plant boilers is not good, consequently, NOX emission is caused, and the coking degree is high, the air distribution method and system reducing NOX emission and relieving coking are provided. According to the air distribution method, hot primary air in a hot primary air mother pipe serves as an air source, air is supplied to a coal-fired boiler hearth, the air speed is high, the air pressure is increased, supplied air can deep penetrate the interior of smoke, pulverized coal incompletely combusted and carbon dioxide and other combustible gases generated by incomplete combustion of the pulverized coal continue to be sufficiently combusted, and therefore NOX emission is reduced, coking of a water wall is relieved, heat losses caused by incomplete combustion