【作者】 王晓磊；

【导师】 郭治； 曲思建；

【作者基本信息】 煤炭科学研究总院 ， 化学工艺， 2008， 硕士

【摘要】 焦炭热态反应性能够较好地反映其在高炉中抵抗化学侵蚀的能力,是评价焦炭质量的重要指标。本文以研究典型碱金属、碱土金属对不同变质程度煤焦-CO₂反应性,以及同种煤不同密度级富集物焦-CO₂反应性的催化作用关系为目的,通过添加K₂CO₃、Na₂CO₃、CaCO₃和MgO到煤（或各密度级富集物）中炼焦,研究了碱金属、碱土金属对焦炭催化溶损反应动力学,初步探讨了焦炭的溶损反应原因,得出了碱对不同煤岩组成的催化作用关系。研究结果表明:添加碱金属、碱土金属对气煤焦炭反应性的影响小于对焦煤焦炭的影响。同种碱金属、碱土金属随添加量的增加,焦炭转化率越大。随溶损反应时间的增加,焦炭转化率逐步增加。其他条件相同时,添加K₂CO₃对焦炭转化率的影响最大,其他依次为Na₂CO₃,CaCO₃和MgO。对于焦煤而言,加碱后镜质组对应的焦炭显微结构的反应活性变大。自身碱含量低的焦炭,加碱后溶损反应中CO₂转化率增加幅度大于自身碱含量高的焦炭。动力学研究表明,对于气煤焦炭,加碱的催化作用在于降低了反应的活化能。而焦煤焦炭添加0.5%的Na₂CO₃、CaCO₃和MgO时,活化能增加,表明反应速率对温度的敏感程度加强,且指前因子相应增大,表明提供了更多的反应活性点,随添加量的增加,活化能降低成为影响反应速率的主要因素。碱金属、碱土金属对焦炭溶损反应的催化作用是由降低反应活化能和增加活性中心共同作用的结果。更多还原

【Abstract】 The coke reactivity index （CRI） is a significant index for evaluating coke qualities, which is more suitable for the abilities of the coke for resisting chemical destruction in blast furnace.With the purposes of studying the catalysis relationship of typical alkali and alkaline metals to the coke reactivity, by adding K₂CO₃、Na₂CO₃、CaCO₃ and MgO to different rank coals and adding K₂CO₃ and CaCO₃ to different density levels of one kind of coal for caking, the catalysis dissolution reaction kinetics of typical alkali and alkaline metals to cokes is studied, the reason of coke dissolution reaction is discussed and the catalysis relationship of typical alkali and alkaline metals to different maceral compositions are elicited. The summery of the results as follows:The influence of typical alkali and alkaline metals to the reactivity of coke from gas coal is lower than it from coking coal. Along with the increasing of quantities of typical alkali and alkaline metals or reaction time, the percent conversion of coke increased. Under the same conditions, the influence sequence of coke percent conversion is K₂CO₃, Na₂CO₃、CaCO₃ and MgO. With catalysis of typical alkali and alkaline metals, the coke with lower alkali itself have higher percent conversion. And the microstructure composition corresponding the vitrinite of coking coal has higher reactivity.The kinetics studying shows that adding alkali can reduce the activity energy of coke dissolution reaction which from gas coal. Adding 0.5% Na₂CO₃、CaCO₃ and MgO to coking coal for caking, the activity energy of the coke dissolution reaction increasing, it means that the sensitivity degree of reaction rate to temperature is stronger. At the same time, the increasing pre-exponential factor means more active spots, Along with the increase of adding quantity, activity energy decreased which becoming the main factor of influencing reaction rate. The catalysis of typical alkali and alkaline metals to the coke reactivity is the result of activity energy decrease and active spots increase.更多还原