A kinetic model based on TGA data for pyrolysis of Zhundong coal

doi:10.11949/j.issn.0438-1157.20161335

Abstract

Abstract:

In order to predict the yield of volatiles and reaction performance during pyrolysis of Zhundong coal, which is of significant importance for its thermal processing, a kinetic model is necessary. The devolatilization of Zhundong coal is characterized by thermo-gravimetric analysis (TGA) at different heating rates. Three types of iso-conversion kinetic models, i.e., Friedman, Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose(KAS), are employed to fit TGA data for pyrolysis of Zhundong coal. The pre-exponential factors and activation energies obtained from different kinetic models are analyzed. The results show that there exists unimodal distribution for the activation energies and the FWO model is better for description of pyrolysis process of Zhundong coal.

Key words: coal, pyrolysis, thermogravimetry analysis, iso-conversional, kinetics, model

摘要：

准东煤热解脱挥发分特性对其热加工利用过程具有重要影响，建立准东煤热解通用动力学模型对预测挥发分产率及反应性能具有重要意义。采用热重测量了不同升温速率条件下的准东煤脱挥发分失重特性，使用Friedman、Flynn-Wall-Ozawa（FWO）和Kissinger-Akahira-Sunose（KAS）3种等转化率模型来处理热重实验数据，仔细分析了不同模型参数的获得方法及不同模型中活化能及指前因子的差异。研究结果表明，准东煤活化能分布函数呈现单峰分布；相比其他模型，FWO模型能够较好地描述准东煤的热解过程。

关键词: 煤, 热解, 热重分析, 等转化率, 动力学, 模型

CLC Number:

TQ530.2

JIANG Guodong, WEI Liping, TENG Haipeng, HAO Huidi. A kinetic model based on TGA data for pyrolysis of Zhundong coal[J]. CIESC Journal, 2017, 68(4): 1415-1422.

江国栋, 魏利平, 滕海鹏, 郝惠娣. 基于热重法的准东煤等转化率热解动力学模型[J]. 化工学报, 2017, 68(4): 1415-1422.

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