Flue gas mixing ultra-low nitrogen burner for cracking furnace

The invention discloses a flue gas mixing ultra-low nitrogen burner for a cracking furnace, and relates to the field of fuel combustion and environmental protection, and the flue gas mixing ultra-low nitrogen burner comprises an air bellow, a burner block, a fuel gas ascending pipe, a fuel gas nozzle, a mixing pipe and the like. The burner bellows upper flange is connected to the bottom of the cracking furnace, the furnace bottom is provided with a furnace bottom installation cylinder, the burner block is located in the furnace bottom installation cylinder and provided with an air circulation channel, one end of the air circulation channel is communicated with the bellows, and the other end of the air circulation channel is communicated with the interior of the hearth. One end of the gas ascending pipe is communicated to the gas pipeline, the other end of the gas ascending pipe penetrates through the burner block, enters the hearth and is connected with the gas nozzle, and the gas nozzle is provided with a si