Structural evolution of iron components and their action behavior on lignite combustion  

作　　者：Jialin Chen Zhenghao Yan Runxia He Yanpeng Ban Huacong Zhou Quansheng Liu 

机构地区：[1]College of Chemical Engineering,Inner Mongolia University of Technology,Inner Mongolia Key Laboratory of High-Value Functional Utilization of Low Rank Carbon Resources,Huhhot 010051,China

出　　处：《Chinese Journal of Chemical Engineering》2025年第2期251-262,共12页中国化学工程学报(英文版)

基　　金：support from the National Natural Science Foundation of China(22368038,21968021,22308048);Science and Technology Plan Project of Inner Mongolia(2020GG0289);Natural Science Foundation of Inner Mongolia(2019MS02025);Science Fund for Distinguished Young Scholars of Inner Mongolia(2022JQ04).

摘　　要：Spontaneous combustion of lignite is closely related to the inherent minerals it contains, and the iron component has a remarkable influence on the combustion property of lignite. It is very important to study the influence of iron component on the combustion reaction property of lignite to reveal autoignition mechanism of lignite and reduce autoignition of lignite. In this research, FeCl_(3) and Fe_(2)O_(3) were doped into demineralised lignite (SL+) by impregnation to research the effects of iron salts and iron oxides on the combustion properties of lignite. Based on the above, the effects of post-treatment method of the FeCl_(3)-doped coal samples, iron-salt hydrolysis products and heat-treated temperatures on the combustion property of lignite were researched, and the microstructures of the coal samples were characterised and analysed using Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope-energy dispersive spectrometer (SEM-EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results demonstrate that doping with FeCl_(3) increases the combustion performance of lignite, thereby reducing the ignition temperature of lignite by approximately 112 ℃. In contrast, doping with Fe_(2)O_(3) has a weaker combustion-promoting effect. XRD and XPS characterisation indicates that iron species in the coal samples doped with iron salts are highly dispersed and exhibit the FeOOH structure, whereas iron species in the coal samples doped with Fe_(2)O_(3) exhibit the crystal form of α-Fe_(2)O_(3). Doping of lignite with FeCl_(3) and its hydrolysis product β-FeOOH reduces the ignition temperature of the coal samples. Iron species in the FeCl_(3)-doped coal samples after heat treatment at 300–500 ℃ increase the combustion property of the coal samples, whereas iron species after heat treatment at 600–900 ℃ have a much weaker or non-existent promoting effect on the combustion performance of the coal samples. The characterisation show a change in iron species in the coal

关 键 词：Coal combustion Microstructure Iron speciation OXIDATION DYNAMICS 

分 类 号：TQ531[化学工程—煤化学工程]