Pulverized coal flame preheating reburning system

A pulverized coal flame preheating reburning system comprises a main boiler burner and a reburning device. A plurality of sets of primary air pipes are arranged at the front end of a preheating chamber of the reburning device, an injection port communicated with a reburning area of the main boiler burner is arranged at the rear end of the preheating chamber of the reburning device, the primary air pipes comprise inner primary air pipes and outer primary air pipes, and inlets of the inner primary air pipes are communicated with a pulverized coal feeding device; the inlet of a gas burner preheating chamber is provided with an ignition detection electrode and a gas burner air-supporting pipeline, and a gas pipeline with a gas burner gas spray head is arranged in the gas burner preheating chamber. The amount of gas needed for the system accounts for 0.3-0.5% of total boiler heat input, gas burns in the preheating chamber of the reburning device, formed naked light is used for providing a stable ignition source, and heat in the preheating chamber of the reburning device is provided by volatile matter generated through pyrolysis of pulverized coal, namely heat is provided by the pulverized coal feeding device. Meanwhile, O2 in primary air for conveying the pulverized coal can be completely consumed away, and nitrogen-containing compounds generated by the pulverized coal which is heated and pyrolyzed can be effectively reduced to N2 under the strong reducing atmosphere.