高炉炉缸炭砖保护层的形成机理及影响因素

Formation Mechanism and Influencing Factors of Carbon Brick Protection Layer in BF Hearth

阐述了高炉炉缸炭砖保护层4种类型(即富铁层、富渣层、富石墨层和富钛层)的形成机理,并用案例印证了炉缸炭砖保护层是4种类型保护层综合作用的结果。重点阐明了影响炉缸炭砖保护层的若干因素,认为:(1)炉缸炭砖保护层形成和稳定的关键是砖衬热面温度,为此必须做好有关冷却系统的设计、建安、护炉及生产维护等工作;(2)要维持与冶炼强度相适应的炉腹煤气量来组织生产,以利于形成稳定的炉缸炭砖保护层;(3)控制好铁水成分,以减缓炭砖保护层的消蚀;(4)提高炉缸死料堆的透气性和透液性,有利于炉缸炭砖保护层的形成和稳定;(5)做好炉前出铁工作,是形成稳定保护层的有效保证。

The formation mechanism of four carbon brick protective layers of BF hearth （ i. e. iron-rich layer, slag-rich lay- er, graphite-rich layer and titanium-rich layer） is expounded with demonstration by actual cases that the protection function of the carbon brick protective layer mainly relies on commonly action of these four layers comprehensively. After highlighting the factors influencing the carbon brick protection layer, then it is pointed out （ 1 ） the hot face temperature of brick lining is critical to the formation and stabilization of the protective layers, thus it is necessary to properly carry out design and installa- tion of the cooling system, implement furnace protection and production maintenance; （2） the bosh gas flow shall be kept at the rate suitable for the smelting intensity during production organization in order to form stable carbon brick protective layer; （ 3 ） the hot metal chemical composition shall be controlled appropriately to weaken erosion of the carbon brick protective layer; （4） the gas permeability and liquid permeability of dead stock shall be enhanced at hearth to form and stabilize carbon brick protective layer; （ 5 ） preparation work before tapping is precondition of forming stable carbon brick protection layer.