Adjustable center feeding rotational flow coal dust shade burner

Abstract

The invention relates to an adjustable center feeding rotational flow coal dust shade burner, comprising a nozzle, a shrinking-expanding Venturi rube, a bent tube and a straight tube. Circumferential air flow deflectors are installed at the periphery of the nozzle and are connected with a circumferential air channel. The nozzle is connected to the outlet of the shrinking-expanding Venturi rube, the inlet of the shrinking-expanding Venturi rube is connected with the bent tube, and the lower end of the bent tube is connected with the straight tube. The nozzle can swing. A groove is arranged on the wall surface at the outlet of the shrinking-expanding Venturi rube, a ceramic fluid director is arranged in the groove and is pressed and fixed by using a pressing and fixing device. A bias block is fixed on the inner wall of the straight tube. The invention realizes a double shade burning mode of thick inside and thin outside as well as thick top and thin bottom, and has the advantages of low ignition point, stable burning, low generation of oxynitride, effective avoidance of coking and the like.

Description

technical field [0001] The invention relates to the technical field of dense-lean combustion of pulverized coal, in particular to a combustion-stabilized, low-NO X Center feed powder swirl burner with adjustable pulverized coal concentration to generate volume and avoid burner inner wall coking. Background technique [0002] In recent years, the dense-lean separation type dense-lean combustion technology has been widely used in ultra-supercritical boilers that are developing rapidly in my country. However, the rich-lean combustion technologies of the first domestically produced ultra-supercritical boilers still rely entirely on imports, and these imported combustion technologies are basically low-NO X Most of the dense-lean combustion technologies are used in China for the first time or have not been used for a long time. The gas-solid multiphase flow conditions of the pulverized coal thick-lean separation, the combustion mechanism, and the influencing factors of the heat t...

AI Technical Summary

Problems solved by technology

However, the rich-lean combustion technologies of the first domestically produced ultra-supercritical boilers still rely entirely on imports, and these imported combustion technologies are basically low-NO X Most of the dense-lean combustion technologies are used in China for the first time or have not been used for a long time. The gas-solid multi-phase flow conditions, combustion mechanism, and factors affecting the heat transfer deviation of the heating surface in the furnace have not been fully grasped.

The thick-thin separation burner used mainly has the following problems: (1) The concentration ratio of pulverized coal is poorly adjustable; (2) The structure is relatively complex, difficult to manufacture, and difficult to maintain, resulting in low service life and frequent replacement, which affects the normal operation of the boiler , so that the production efficiency of the power plant is affected; (3) it is manufactured in the form of casting, the wear resistance is poor, and the maximum service temperature is low, and the pulverized coal burner is often damaged or broken down by the pulverized coal; (4) the inner wall of the burner Severe dust and slagging

For example, the first batch of domestic HG-2953 / 27.46-YM1 and DG3000 / 26.15-II 1 ultra-supercritical boilers respectively adopt low NO X The thick-thin PM burner and the HT-NR3 thick-thin burner have encountered problems such as coking and sintering of the primary air powder tube of the burner since they were put into operation.

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