煤焦燃烧反应动力学参数与煤种的通用关系

根据作者以前提出的关于煤焦在空气中燃烧的表面反应动力学的新思想，即其表面反应活化能Ｅ与煤种无关，只取决于其温度，但其反应频率因子ｋ０，ｃｈ与煤种有密切关系，在此基础上，本文提出了一种确定煤焦燃烧反应动力学参数的新方法。在这一方法中，确定了Ｅ＝１８０ｋＪ／ｍｏｌ，它适用于在空气中燃烧的任何一种煤焦的反应。

A Generalized Relationship between the Kinetic Parameters of Char Combustion and Coal Properties

According to our previous new idea for kinetics of char oxidation, an approach for determining kinetic parameters of char combustion, in which the activation energy, E , is independent of coal properties and only varies with the temperature of the char particle and the frequency factor of char oxidation, k 0,ch , is dependent on coal properties during its burning in air, is presented in this paper. We have taken a value of E =180 kJ/mol, which is a constant in the oxidation of any kind of coal char in air. Based on experiments for different coals, a fitted relationship between k 0,ch and coal properties, applicable to any kind of coal char burning in air, is given in the paper. It is different from those proposed in previous literatures in which both E and k 0,ch vary disorderly with coal properties. Now the value of k 0,ch can easily be predicted from the known proximate analysis of coal. The proposed generalized relationship for determining the kinetic parameters of char combustion is very useful for engineering purpose and coal combustion modellers for predicting the burning rate of different type of coal. Furthermore, it can be demonstrated that the k 0,ch is related to not only the coal properties but also the burning regime, and a quantitative relationship between them is also presented in this paper.