煤中高挥发分促进Fe_(3)O_(4)非等温还原动力学机制研究  

Mechanism of high volatile matter in coal promoting non-isothermal reduction of Fe_(3)O_(4)

作　　者：杨永坤 王冠杰 周欣 申雯婷 王伟安 王国华 李小明[1] YANG Yongkun;WANG Guanjie;ZHOU Xin;SHEN Wenting;WANG Weian;WANG Guohua;LI Xiaoming(School of Metallurgical Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,Shaanxi,China)

机构地区：[1]西安建筑科技大学冶金工程学院,陕西西安710055

出　　处：《钢铁研究学报》2025年第3期307-316,共10页Journal of Iron and Steel Research

基　　金：国家自然科学基金资助项目(U22A20175,52304358);中国科协青年人才托举工程资助项目(YESS 20230462)。

摘　　要：随电炉炼钢的发展,对于直接还原铁的需求也将增加,使用煤低温还原优选磁铁矿是直接还原铁的重要来源。为了研究煤中高挥发分对直接还原Fe_(3)O_(4)的促进机制,使用气相色谱仪和热重-质谱联用装置分析了广汇煤热解气体成分与热解特性,采用非等温热分析方法对活性炭与广汇煤还原Fe_(3)O_(4)进行了研究,利用FWO、KAS、Starink3种方法计算了反应活化能,使用Satava-Sestak法拟合反应模型,着重比较了活性炭与广汇煤还原Fe_(3)O_(4)的动力学机制差异。结果表明:广汇煤的干馏煤气组成主要为H_(2)、CH_(4)、CO和CO_(2),在还原温度区间H_(2)体积分数可达55%、CO体积分数可达25%,为Fe_(3)O_(4)的还原提供了良好的气氛条件;活性炭还原温度区间在980~1140℃,初始阶段活化能为319.66k J/mol,而广汇煤还原温度区间为680~1030℃,初始阶段活化能为288.62k J/mol,表明广汇煤中挥发分在还原过程中起到了促进作用,显著降低了还原温度及活化能。With the development of electric arc furnace,the demand for direct reduced iron will also increase.The useof low temperature reduction to optimize magnetite is an important source of direct reduced iron.In order to stud ythe mechanism of Fe_(3)O_(4) reduction promoted by highvolatile matter in coal,the pyrolysis gas composition andpyrolysis characteristics of Guanghui coal were analyzed.The pyrolysis of Guanghui coal and Fe_(3)O_(4) reduction were studied by non-isothermal kinetics analysis method.The activation energy of the reaction was calculated by FWO,KAS and St arink methods.The Satava-Sestak method was used to fit the reaction model.The difference of kineticmechanismof Fe_(3)O_(4) reduction between activated carbon and al was emphasized.The results show that thereto rting gas of Guanghui coal is mainly composed of H_(2),cCH_(4),oCO and CO_(2).In the reduction temperature range,the H_(2) content and CO content of coal pyrolysis can reach 55 and 25 vol.%,respectively,which provides a goodatmosphere for the reduction of Fe_(3)O_(4).The temperature range of activated carbon reduction of Fe_(3)O_(4) is 980-1140℃,and the initial activation energy is 319.66kJ/mol,while the reduction temperature range of Guangh ui coal is 680-1030℃,and the initial activation energy is 288.62kJ/mol.The results show that the high volatilem atter in Guanghui coal plays a catalytic role in the reduction process and significantly reduces the reductiontemperature and activation energy.

关 键 词：煤基 挥发分 还原动力学 活化能 机制函数 

分 类 号：TF55[冶金工程—钢铁冶金]