我国钢铁产量与优质焦煤资源、环保形势的矛盾日益突出，优化炼铁工艺，实现高炉降碳减排刻不容缓。提高碳利用率是降低高炉焦比、减少CO2排放的有效措施。铁焦作为一种有望实现工业化应用的铁碳复合炉料，其高反应性可降低高炉热储备区温度，提高炉身工作效率，从而提高碳利用率，因此受到广泛关注。综述了铁焦的发展历程和研究进展，比较了不同铁焦制备工艺的特点和获得铁焦的性能。煤直接配加铁矿粉制备铁焦工艺投资成本小，利用现有焦炉设施即可实现，但需严格控制炼焦炉温度，否则会降低焦炉寿命；热压法铁焦制备工艺可大量使用弱黏结性煤或非黏结煤，制备的铁焦具有较高的反应性和反应后强度，已实现工业化生产和应用；而冷压法制备工艺能进一步降低炼焦能耗，但铁焦产品的强度需优化。炼焦过程中加入煤中的含铁矿物均被还原为金属铁，其氧化反应催化了铁焦在高炉内的气化。针对铁焦强度劣化，提出在制备过程中添加含甲苯、乙苯、邻二甲苯和长支链烷烃等类胶质体的解决方法，为炼制满足高炉要求的高强度-高反应性铁焦提供了可行途径。研究表明，铁焦与含铁炉料混装的布料方式既能实现高炉降碳减排，又不影响高炉透气透液性；铁焦的反应性与反应后强度的协同优化、铁焦在高炉内的递变行为和铁焦对高炉能耗影响是未来的重点研究方向。

The increasing China′s steel output is at odds with the shortage of high-quality coking coal resources and environmental problems. Therefore, it is urgent to optimize ironmaking process, realize energy saving and emission reduction of blast furnace. Improving the carbon utilization rate is an effective measure to reduce the coke ratio of blast furnace and CO2 emission. As a kind of iron-carbon composite burden that is expected to realize industrial application, ferro coke has been extensively studied. Its high reactivity can effectively reduce the temperature of the thermal reserve zone in blast furnace, improve the smelting efficiency, thus reduce coke ratio and carbon emission. In this work, the development history and current research status of ferro coke were reviewed and the characteristics of different ferro coke preparation processes and the properties of ferro coke were compared. The investment cost of preparing ferro coke by directly adding iron ore powder to coal is small, which can be realized by using existing coke oven facilities. However, the temperature of coke oven should be strictly controlled, otherwise the life of coke oven will be reduced. Hot pressing ferro coke preparation process can use a large amount of weakly bonded coal or non-bonded coal, the prepared ferro coke has high reactivity and post-reaction strength, has realized industrial production and application. Cold pressing ferro coke preparation process can further reduce the energy consumption of coking, but the strength of ferro coke needs to be optimized. In coking process, the iron-bearing minerals added to coal are reduced to metal iron, and its oxidation reaction catalyzes the gasification of ferro coke in the blast furnace. In view of the strength deterioration of ferro coke, a solution is proposed to add additives containing metaplast such as toluene, ethylbenzene, oxylene and long branched alkanes during the coking process, which gives a feasible way for preparing high strength and high reactivity ferro coke that meets the requirements of blast furnace. The results show that the mixed charging mode of ferro coke and iron bearing burden can not only reduce carbon emission, but also does not affect the permeability of blast furnace. The synergistic optimization of reactivity and strength of ferro coke, the behavior of ferro coke in blast furnace and the effect of ferro coke on energy consumption of blast furnace are the key research directions in the future.

0 引言

1 铁焦生产的起源与发展历程

2 铁焦的制备工艺及矿相转变

   2.1 铁焦的制备工艺

   2.2 焦化和气化反应过程铁焦的矿物相转变

3 铁焦强度优化

   3.1 铁焦强度劣化机理

   3.2 铁焦强度提升

4 铁焦应用及展望

   4.1 铁焦应用

   4.2 铁焦未来研究展望

5 结论