A direct-flow pulverized coal burner with adjustable primary wind speed for thick and thin phases

Abstract

The invention provides a thick-phase and thin-phase primary wind speed adjustable direct-current pulverized coal burner. The thick-phase and thin-phase primary wind speed adjustable direct-current pulverized coal burner is characterized by comprising a burner bent pipe which is connected with one end of a square-circle switching pipe, the other end of the square-circle switching pipe is connected with one end of a bent pipe, the other end of the bent pipe forms a thin-phase spray nozzle, a thick-phase spray nozzle guide pipe is arranged in the bent pipe, and the front end of the thick-phase spray nozzle guide pipe forms a thick-phase spray nozzle. According to the pulverized coal burner, separation is conducted through the action of centrifugal force of a continuous elbow, the effects of being thick outside and thin inside are achieved, the concentration of thick-phase pulverized coal at the center is increased by about 30%, and the concentration of thin-phase pulverized coal on the periphery is decreased by about 30%. In addition, the concentration of pulverized coal in the thick-phase spray nozzle, the concentration of pulverized coal in the thin-phase spray nozzle, and the primary wind speed can be further changed by adjusting shutter sashes, the adjustable range of the primary wind speed is about 25% of the designed wind speed, and therefore combustion is achieved when the type of coal is changed and loads are changed. Thus, compared with a traditional burner, the thick-phase and thin-phase primary wind speed adjustable direct-current pulverized coal burner has the advantages of being high in ignition stability, good in coking resistance, high in combustion efficiency, low in NOX generation and the like.

Description

technical field [0001] The invention belongs to the technical field of pulverized coal burners in thermal power plants, and relates to a pulverized coal burner with strong ignition stability, good anti-coking performance, high combustion efficiency, and NO X Generate low burner. Background technique [0002] Pulverized coal thick and thin burners are widely used in coal-fired boilers in large thermal power plants. However, most of the pulverized coal thick-lean burners currently in use are horizontal thick-lean burners and vertical thick-lean burners, and central thick-lean burners are relatively rare. At present, once the construction and installation of the thick-lean burner is completed, the concentration of the thick-lean phase cannot be adjusted; even if it can be adjusted, it is a small fine-tuning. In short, the currently used thick-lean burners mainly have the following problems: (1) The primary wind speed of the pulverized coal thick-lean phase is poorly adjustabl...

AI Technical Summary

Problems solved by technology

However, most of the pulverized coal thick-lean burners currently in use are horizontal thick-lean burners and vertical thick-lean burners, and the central thick-lean burner is relatively seldom used.

At present, once the construction and installation of the thick-lean burner is completed, the concentration of the thick-lean phase cannot be adjusted; even if it can be adjusted, it is a small fine-tuning

In short, the thick-lean burners currently in use mainly have the following problems: (1) The primary wind speed of the pulverized coal thick-lean phase is poorly adjustable, and the adjustment range is small; (2) The coal type is poorly adaptable

(3) Poor load adaptability

Generally speaking, the thermal load adjustment of power plant boilers is relatively frequent, and the primary air concentration varies greatly under different thermal loads, which is not good for combustion. Therefore, the thick-lean burner needs to adjust the primary air velocity and pulverized coal concentration according to different loads; (4) The structure is complex, Not easy to repair, not easy to replace

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