Structural Design and Performance Analysis for Pulverized Coal Burner of Aggregate Drying

doi:10.3901/JME.2025.02.310

Abstract

Abstract: The structure of aggregate drying pulverized coal burner correlates with its internal flow field, and further affects the pulverized coal combustion effect. The swirl, swirl-steady combustion and swirl-dense thin separation pulverized coal burner of aggregate drying were designed based on swirl, steady combustion and dense thin separation technology. The influence of pulverized coal burner structure on the burner performance based on pulverized coal combustion efficiency and NO emission as evaluation indexes under different air distribution parameters was investigated by numerical simulation. The optimum structure of pulverized coal burner was determined. Based on this, the aggregate drying pulverized coal combustion experiment was built, and the numerical simulation was verified by pulverized coal combustion tests. The results indicated that the combustion efficiency can be greatly improved and the emission can be reduced of aggregate drying pulverized coal burner using the swirl and dense thin separation approach. The air distribution parameters have a certain impact on the combustion efficiency and NO emission of the three types of burners, with the swirl-dense thin separation pulverized coal burner being the least affected. The performance of the swirl-dense thin separation pulverized coal burner is superior to that of swirl and swirl-steady combustion type. According to the test results, the NO emission of the swirl-dense thin separation pulverized coal burner is 31.4% lower than that of swirl burner. This study suggests an effective approach for the study of pulverized coal combustion mechanism of pulverized coal burner of aggregate drying, and provides a basis for exploring the burner structure of aggregate drying equipment using pulverized coal as fuel.

Key words: aggregate drying, pulverized coal burner, swirl, steady combustion, dense thin separation

CLC Number:

TQ534

CHENG Haiying, LI Xuan, GAO Ruifa, YAN Wengang, HU Zhiyong. Structural Design and Performance Analysis for Pulverized Coal Burner of Aggregate Drying[J]. Journal of Mechanical Engineering, 2025, 61(2): 310-320.

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