Transformation method applicable to combustion use Zhundong coal boiler bottom ash hopper slag stacking prevention structure

Abstract

The invention discloses a transformation method applicable to a combustion use Zhundong coal boiler bottom ash hopper slag stacking prevention structure. The method comprises the step that a refractory belt is laid on the surface of a bottom ash hopper to prevent molten slag flowing down from a vertical water-cooling wall from being cooled and solidified by the water-cooling wall and being piled in the bottom ash hopper, and large slag blocks which cannot be discharged smoothly cannot be formed, the thickness of the laid refractory belt is reduced from high to low, and it is ensured that a steeper slope is formed compared with an original bottom ash hopper so as not to affect the size of a slag discharging port, so that smooth discharging of the molten slag is promoted. The transformationmethod is simple and low in cost. Bottom slag in a combustion use Zhundong high-alkaline pulverized coal boiler can be discharged smoothly. The transformation method can be used for not only design ofa novel boiler but also transformation of an existing boiler. Inconvenience and potential safety hazards caused by manual slag removal are avoided.

Description

technical field [0001] The invention relates to a slag removal method, more specifically to a method for improving the anti-slagging structure of the cold ash hopper of the Zhundong coal-fired boiler. Background technique [0002] Zhundong high-alkali coal has high volatile content and has a grindability index greater than 80. This type of coal has good grindability, ignition and burnout properties, but it also has strong slagging and caking properties, and the ash The melting point is low, about 1130~1190 ℃. In the operation of pulverized coal boilers burning Zhundong high-alkali coal, because the coal is rich in alkali metals, the surface of the water-cooled wall in the furnace is almost completely covered by the slag layer, which flows along the water-cooled wall to the cold ash hopper in a molten state, and The cold ash hopper cools and solidifies, piles up and forms a blockage. When a power plant boiler burns this type of coal, a 2-5 cm liquid slag is formed on the su...

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Problems solved by technology

[0005] The purpose of the present invention is to overcome the problem that when the power plant boiler burns coal with a low ash melting point, a fluidized layer is formed on the surface of the water cooling wall and condenses and piles up at the inflection point at the upper end of the cold ash hopper to form a blockage. Using the anti-slagging structure modification method of Zhundong coal boiler cold ash hopper, the present invention is applicable to any power plant boiler that burns coal with a lower ash melting point, and can make adjustments under different boiler loads to ensure that the surface temperature of the cold ash hopper is higher than that of the ash. Slag fluidization temperature FT, so that the slag can slide smoothly to the slag well, avoiding the inconvenience and safety hazards caused by manual slag removal

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