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球团矿在高炉中的性状是球团矿和焦炭的特性相互作用的结果,也是高炉特性和操作条件交互影响的结果。过去二十多年来,高炉生产以低燃耗和高产率为目的的趋势已日益增加。要达到这一目的,只能靠比较有效地应用作为化学试剂的碳来完成,通过高风温和高的火焰温度,其热效应比较容易得到利用。此外,金属化最好是通过气一固反应来完成,从而使之发生在球团中大量形成液相渣之前。液相渣形成的动力学过程取决于焙烧球团中的渣相和脉石的性质和数量,也与其在高炉内的相对还原速度和加热速度有关。焙烧球团矿中粘结剂的数量、热稳定性和化学稳定性对球团矿的强度、低温扮化率(LTB)、膨胀率以及中、高温还原率有很大的影响。有一点必须看到,酸性球团矿和熔剂性球团矿的强度和还原度常常不能同时达最大值,对它们必须综合考虑。近年来,解析了用熔剂性球团矿所做的高炉试验。较好地弄清造球和还原的机理将有助于制造出为炼铁使用的质量良好的球团矿。
The nature of the pellets in the blast furnace is the result of the interaction between the characteristics of the pellets and the coke and the result of the interaction between the characteristics of the blast furnace and the operating conditions. Over the past two decades, there has been an increasing trend toward the goal of low burnup and high yield of blast furnace production. This can only be accomplished by using carbon as a chemical reagent more efficiently, and its thermal effects are easier to exploit through high temperature and high flame temperatures. In addition, metallisation is best accomplished by gas-solid reaction, so that it occurs prior to extensive formation of liquid slag in the pellets. The kinetics of the formation of liquid slag depend on the nature and amount of slag phase and gangue in the pellet, as well as its relative reduction rate and heating rate in the blast furnace. The amount, thermal stability and chemical stability of binder in roasting pellets have a great influence on the strength of pellets, LTB, swelling ratio and medium and high temperature reduction rate. It is important to note that the strength and reduction of acidic pellets and flux pellets often can not reach their maximum at the same time and must be considered together. In recent years, blast furnace tests done using flux pellets have been analyzed. Better understanding of the mechanism of pelletizing and reduction will help to produce good quality pellets for ironmaking.