Low -nitrogen combustion transformation method reduces boiler flue gas NOx's device

The utility model discloses a low -nitrogen combustion transformation method reduces boiler flue gas NOx's device, including consecutive boiler, cyclone, economizer, dust remover, draught fan and chimney, the middle part of boiler and bottom be connected with respectively tuber pipe say with the overgrate air pipeline, the entrance of tuber pipe way and overgrate air pipeline is equipped with primary air fan and overfire air fan respectively, a gas recirculation flue is drawn with the exit that the chimney is connected to the draught fan, the other end of gas recirculation flue connects in parallel to the entrance of primary air fan, tuber pipe says and is equipped with air heater respectively with the middle section of overgrate air pipeline, and the hierarchical pipeline of a wind is drawn by a tuber pipe taoist scriptures air heater's outlet header department, and the other end of a hierarchical pipeline of wind connects in parallel to secondary air channel taoist scriptures air heater's outlet header department. This reduction boiler flue gas NOx device only needs to install two pipelines additional on the basis of existing equipment, has investment cost and hangs down, reforms transform advantage swift, easy operation.