高炉喷吹固体燃料物化结构与燃烧性能关系研究

Study on Relationship between Physicochemical Structure and Combustion Characteristics of Solid Fuels Injected into BF

高炉喷吹煤粉技术是现代钢铁企业降本增效的主要技术措施,喷吹固体燃料的燃烧性能是提升煤焦置换比的关键。为明确影响高炉喷吹固体燃料燃烧性能的关键因素,系统分析了不同固体燃料的物化结构与其燃烧性能的关系。结果表明,高炉喷吹固体燃料中碳结构的有序化程度对其燃烧性能有显著的影响,有序化程度越高的样品,在燃烧反应过程中需要更高的能量破坏芳香环的结构,造成其着火温度升高,燃烧速率降低。高炉喷吹煤粉技术在喷吹燃料选择和使用过程中,选取固定碳含量高、发热值高、孔隙结构发达、富含有机官能团和碳结构有序化程度较低的固体燃料进行高炉喷吹,可以有效改善混合煤粉在风口前的燃烧状态,提升高炉喷吹煤粉在炉内的利用率。

The technology of injecting pulverized coal into a blast furnace(BF)is the main technical measure to reduce cost and increase efficiency in modern iron and steel enterprises,while the combustion characteristics of solid fuels for injecting into a BF is the key element in improving the replacement ratio of coals and cokes.In order to clarify the key factors affecting the combustion characteristics of solid fuels injected into BF,the relationship between the physicochemical structure of different solid fuels and their combustion characteristics were systematically analyzed.The analytical results showed that the ordering degree of carbon structures in solid fuels injected into BF had a significant effect on their combustion characteristics.The samples with higher ordering degree needed higher energy to destroy the structure of aromatic ring in the combustion reaction process,resulting in higher ignition temperatures and lower combustion rates.In the process of selecting and using pulverized coals or fuels for injection into a BF by the technology of injecting pulverized coal into a BF,solid fuels with higher content of fixed carbon,higher calorific values,developed pore structures,rich organic functional groups and low degrees of carbon structures with higher ordering degrees were selected for injecting fuels into BF,which could effectively improve the combustion state of mixed pulverized coals before coming into tuyeres and improve the utilization rates of pulverized coals injected into BF.