低气压下链条炉的运行特性与热力计算方法

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中图分类号：TK16文献标志码：A

DOI：10.7652/xjtuxb202508006 文章编号：0253-987X（2025）08-0053-11

Operational Characteristics and Thermodynamic Calculation Method for Chain-Grate Stokers under Low-Pressure Conditions

ZONG Siyu1，DU Yongbo1，XU Qiongl， ZHANG Jingkunl，DA Yaodong²，CHE Defu' （1. School of Energy and Power Engineering，Xi'an Jiaotong University， Xi'an 71Oo49，China; 2.China Special Equipment Inspection and Research Institute，Beijing 1ooo29，China）

Abstract： To address the issues of insufficient output， increased flue gas temperature，and decreased efficiency caused by low pressure in boilers， this study focuses on a 10t/h coal-fired chain grate boiler. A numerical method is employed to analyze the effects of pressure drop on temperature distribution within the furnace，coal burnout，and flue gas parameters at the furnace exit. Through a user-defined function，the motion of coal particles on the grate is simulated，and the three-dimensional physical model is improved to accurately reflect the actual grate structure. Considering the accumulation of ash on the surface of the carbon core during combustion，which hinders oxygen diffusion and affects the combustion rate，the coke combustion model is refined. Numerical results indicate that as pressure decreases，the combustion process of coal particles on the grate is delayed compared to normal pressure， resulting in a reduced coke burnout rate. The （204号 NOx emissions at the furnace exit initially increase and then decrease，with an increase of approximately 8.79% at 77. 273kPa compared to normal pressure. Under low pressure，the reduced blackness of the gas flame leads to decreased radiative heat transfer，causing an increase in the flue gas temperature at the furnace exit. However，when the pressure is too low，the increase in heat loss due to incomplete combustion slightly lowers the furnace exit flue gas temperature. The proposed correction formula for the M number provides a reference for predicting the flue gas temperature at the furnace exit using thermodynamic calculation methods under low pressure conditions.

Keywords： chain boiler; low atmospheric pressure; coal burning； thermodynamic calculation

我国幅员辽阔，海拔高度超过 2 000m 的区域约占国土面积的 30% ，且大多位处西部地区。（剩余17746字）