太钢新建4350 m~3高炉长寿炉缸炉底研究

以太钢新建4 350m3高炉为例,论述了为实现高炉炉缸炉底的长寿,从高炉的设计、选材和砌筑等方面采取的一系列措施。炉缸设计采用"传热法",炉底设计采用"隔热法",炉缸炉底整体设计采用了"扬冷避热梯度布砖法"。炉缸选材使用优质高导热系数的碳砖,为了克服冷却壁与碳砖之间捣打料带来较大热阻,砌筑过程中碳砖采用顶砌冷却壁方式,并且严格控制砖衬宽度;炉壳与冷却壁采用分段灌浆。通过建立炉缸炉底传热数学模型,进一步表明了该高炉炉缸炉底优良的性能,投产后1 150℃等温线位于炉缸砖衬热面附近,有利于渣铁壳的形成;同时碳砖内部温度普遍低于750℃,温度梯度较小,碳砖脆化及热应力对砖衬的破坏作用较轻,为日后实现长寿炉缸炉底创造了必要的条件。

Long Service Life and Heat Transfer Analysis of Hearth Bottom of New 4350m3 Blast Furnace in TISCO

In order to achieve the long service life of hearth bottom, some measures are taken including the design, material selection and masonry of hearth bottom based on the new BF with volume of 4350m3 in TISCO. The “heat transfer method” hearth and “heat isolation method” bottom are utilized for the design. The method of gradient brick laying is applied for the whole hearth bottom. The carbon bricks with high thermal conductivity are chosen for the material selection. In order to decrease the thermal conductivity of filling between staves and carbon bricks, the hearth bricks touch with staves directly during the process of the masonry. The brickwork joints should be also controlled strictly. The segmented grouting is used between furnace shell and cooling staves. The heat transfer mathematical model of hearth bottom is established and the results show the excellent thermal performance of hearth bottom. The isotherm of 1150℃ is near the hot face of lining bricks which is favorable for the formation of slag-iron skull after blow-in. The temperature of carbon bricks is generally below 750℃ and temperature gradient is also small. Therefore, the embrittlement and thermal stress damage of carbon bricks are little, which is the necessary condition for the long service life of hearth bottom.