High-temperature flue gas multi-stage backflow low-nitrogen combustor and combustion method thereof

Abstract

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.

Description

technical field [0001] The invention relates to a high-temperature flue gas multi-stage backflow low-nitrogen burner and a combustion method thereof, belonging to the technical field of combustion. Background technique [0002] With the rapid development of the economy, the rapid increase of energy consumption and the severe situation of global warming, the problem of air pollution has attracted more and more attention. Nitrogen oxides (NOx) are one of the main pollutants in the atmosphere, which can not only form acid rain, but also form PM 2.5 key precursors. Therefore, further control of nitrogen oxide (NOx) emissions is crucial to sustainable development. For natural gas boilers, it is urgent to develop high-efficiency, low-nitrogen burners. [0003] At present, the main low-nitrogen combustion technologies include staged combustion, flameless combustion, flue gas recirculation, premixed combustion, etc. Its technical route mainly revolves around reducing the combust...

AI Technical Summary

Problems solved by technology

Various low-nitrogen combustion technologies have both advantages and disadvantages. For example, air staged combustion is widely used, but the emission reduction effect is limited; flue gas recirculation is simple, but further reduces NO X Emissions will lead to unstable combustion and have a certain impact on the stability of the boiler; lean-burn premixed NOx emission reduction effect is good, but the thermal efficiency of the boiler will decrease, and may cause backfiring or flameout

The flue gas mixing technology in the furnace has been greatly developed in recent years. However, due to the use of the Venturi method for mixing, the uniformity of mixing and the amount of flue gas entrainment are affected by operating parameters, or it is impossible to reduce NO X generate or cause combustion instability

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