Secondary air distribution structure for lowering carbon content of layer-burning boiler fly ash

Abstract

The invention relates to the technical field of controlling pollutant discharge of layer-burning boilers, in particular to a secondary air distribution structure for lowering the carbon content of layer-burning boiler fly ash. The secondary air distribution structure comprises a plurality of sets of secondary air nozzles arranged between a burn-out chamber and a throat of a layer-burning boiler, an oblique secondary air collecting box arranged in a primary air chamber of the layer-burning boiler, and a plurality of oblique secondary air nozzles communicating with the oblique secondary air collecting box; each set of secondary air nozzles comprise four tangential secondary air nozzles; the oblique secondary air nozzles are inclined towards the throat of the layer-burning boiler; the multiple sets of secondary air nozzles are sequentially arranged in a coplanar mode, and an arrangement surface is formed; the arrangement area of the four tangential secondary air nozzles of the same set isused as a bottom surface; the burn-out chamber forms a plurality of parallel chambers perpendicular to the bottom surfaces; the arrangement surfaces form included angles with the horizontal plane; the upward normal lines of the arrangement surfaces are pointed to the outer top corner of the burn-out chamber; the four tangential secondary air nozzles of the same set are arranged at the four corners of the corresponding bottom surfaces correspondingly; and the jet directions of the four tangential secondary air nozzles of the same set are tangent to a common tangential circle of the centers ofthe corresponding bottom surfaces.

Description

technical field [0001] The invention relates to the technical field of pollutant discharge control of a floor-fired boiler, in particular to a secondary air distribution structure for reducing the carbon content of fly ash of a floor-fired boiler. Background technique [0002] The number of coal-fired boilers in my country is about 700,000 units, with a total capacity of 4 million MW and an annual consumption of more than 700 million tons of standard coal. Coal-fired boilers consume a huge amount of energy and discharge pollutants, which is one of the main sources of pollution that causes frequent smog in winter in my country. In order to speed up the transformation of the economic development mode and vigorously promote the construction of ecological civilization, the state has issued the latest standards on the control of air pollutant emissions from coal-fired boilers. Some provinces, cities and regions have also formulated local laws and regulations based on their own co...

AI Technical Summary

Problems solved by technology

The secondary air of traditional coal-fired boilers mostly adopts the radial air distribution method with the front and rear walls blowing against each other, which has problems such as poor jet penetration and disturbance ability, uneven oxygen distribution in the burnout chamber, and a large number of pulverized coal particles entrained by flue gas. After full combustion, it will be discharged from the burnout chamber, resulting in a high carbon content in the fly ash of the flue gas at the tail of the boiler. Therefore, a new type of secondary air distribution structure is urgently needed to actively reduce the carbon content of the fly ash in the flue gas at the bottom of the layer combustion furnace. quantity

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