基于焦炭综合热性质的炼焦配煤基础理论研究

The project “Study on the coal blending and coking theory based on comprehensive thermal properties of coke” is proposed in hopes of exactly evaluating the thermoplastic properties of coking coal, developing new evaluation index of thermal properties of coke and elucidating the reasons for the utilization of abnormal coking coals and cokes with different CSR in blast furnace. Firstly, it aims at the relationship between the chemical structure and the properties of vitrinite of coking coals in order to indicate the discrepancy of the thermoplastic properties of some coals with similar rank and explain the similarity of the thermoplastic properties of some coals with different ranks. Then the effects of pyrolysis and charging of vitrinite on pore formation and the hierarchical structures of coke are investigated to formulate evaluation and characteristic index of pore-forming. It also studies the interactions between pyrolysis products and charging process of coking coals. The interaction mechanism of coal macerals in the charging process is clarified on that basis. The effects of the interaction level of coal macerals on the charging process and hierarchical structure of coke are studied as well, which may help to improve the coal blending theory. Finally the research focuses on the relationships between solution loss reaction of coke and reduction, heat exchange and coke degradation in blast furnace, and the analysis of the limitation of CRI and CSR. A more scientific index system of comprehensive thermal properties of coke is being established. The research results will play important role in extending coking coal resources, reducing cokemaking cost and directing blast furnace production theoretically and practically.

为了补充炼焦煤黏结性评价指标、构建新的焦炭热性质评价体系，阐明性质异常煤在炼焦配煤中应用以及CSR指标相差很大的焦炭可在高炉上应用的原因，提出了“基于焦炭综合热性质的炼焦配煤基础理论研究”的项目。本项目拟研究镜质组的性质与化学结构之间的关系，揭示某些相同变质程度镜质组黏结性有差异或不同变质程度镜质组黏结性相近的原因；研究镜质组热解、成焦行为对气孔产生机制和焦炭不同层次结构的影响，探索炼焦煤成孔性的评价与表征指标；通过研究炼焦煤的热解行为及热解产物之间的交互作用，阐明显微组分在干馏过程中的交互作用机理，揭示交互作用程度对成焦行为、焦炭不同层次结构的影响规律，完善炼焦配煤理论；深入研究焦炭溶损反应与高炉还原、热交换和焦炭劣化之间的关系，分析CRI和CSR指标模拟性存在的问题，构建更加科学的焦炭综合热性质指标体系。研究成果对扩大炼焦煤资源、降低炼焦成本、指导高炉生产具有重要的理论意义和应用价值。

本课题从性质异常炼焦煤的结构、粘结性能及成焦机制、焦炭在高炉中的溶损机理及焦炭热性能的科学评价等内容开展了五个方面的研究。（1）在系统研究了焦炭在高炉中溶损反应动力学的基础上建立了焦炭综合热性质评价体系，提出了更为科学的评价指标并在攀钢、包钢、唐钢等国内多家企业得到应用。（2）系统地研究了煤中活、惰组分在成焦过程中的相互作用程度在焦炭的冷强度和热性能上表现的差异性规律，并提出了镜质组容惰能力的评价指标，制定了相应的配煤方案模型。（3）为了评价炼焦煤各种性质在成焦过程中的协同交互作用，开发了一套炼焦煤黏结成焦关联性检测装置，其联动结构可以实现胶质层厚度、膨胀收缩行为、膨胀压力和挥发分逸出行为的同步检测，清晰反映出炼焦煤碳化过程中各塑性指标的关联和交互作用，完善了现有炼焦煤质评价体系。该体系正在攀钢进行转化实施并逐渐在其他企业推广。（4）根据炼焦煤镜质组三维荧光光谱的差异提炼出了特性荧光参数，该参数可以在分子结构水平上揭示煤的黏结性的差异。用活性反应力场方法进行的分子动力学模拟可以在分子水平上解析煤的热解机制。课题组首次从炼焦煤的化学结构入手，解决了焦化工艺生产中“性质异常煤”的问题，从炼焦煤化学结构层面提炼新指标表征炼焦煤的成焦性质。（5）从原子层面分析了焦炭的类石墨化微晶结构，定量地阐明了焦炭微米级气孔的形成机制和影响因素和纳米级孔的形成规律，揭示了焦炭光学组织的行成与孔结构发展的关联性，确定了矿物质对焦炭溶损反应的协同催化作用及最佳配比。这些对焦炭不同层次性质的研究为基于焦炭热性质的精细化配煤技术奠定了理论基础。项目培养研究生十余人，申请专利6项，发表论文40余篇。