The invention discloses a high-temperature
flue gas multi-stage
backflow low-
nitrogen combustor and a
combustion method thereof. The
combustor comprises a shell, a fuel main
pipe and a
combustion head, wherein the fuel main
pipe is arranged in the shell, and an
air channel is formed between the fuel main
pipe and the shell; the
combustion head comprises a connecting pipe, a secondary fuel pipe, aprimary fuel pipe, a secondary
fuel distribution ring pipe and a
rotational flow disc; the secondary
fuel distribution ring pipe is arranged on the periphery of the
rotational flow disc in a concentric circle mode, and the secondary
fuel distribution ring pipe and the
rotational flow disc jointly serve as an outlet of the combustion head; and vortex plates are arranged on the inner wall surface ofthe front end of the shell, and the vortex plates are arranged at
flue gas
backflow holes in a one-to-one correspondence mode. Primary air and
fuel gas enter the
combustor through the
air channel andthe fuel main pipe correspondingly; and the
fuel gas is divided into primary
fuel gas and secondary fuel gas through the primary fuel pipe and the secondary fuel pipe correspondingly. The primary fuel gas forms an on-duty
flame at the center of the rotational flow disc. The secondary fuel gas and air form high-speed
jet flow, and high-temperature
flue gas is entrained to form multi-stage
backflow. The high-temperature
flue gas multi-stage backflow low-
nitrogen combustor has the advantages of fuel grading,
flame dispersion, low
NOx combustion and the like.