共查询到19条相似文献,搜索用时 156 毫秒
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以硫酸渣和煤粉为主要原料,对硫酸渣含碳球团进行焙烧,考察焙烧时间、焙烧温度、配碳量对球团金属化率的影响,确定了最佳工艺参数,即焙烧温度为1 225℃、焙烧时间15 min、(C)/(O)为1.2时,球团金属化率可达92.5%,此工艺参数满足转底炉高效还原的特点,适用于转底炉工艺。 相似文献
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以低品位红土镍矿(w(TFe)=22%、w(Ni) =1.89%)为原料,运用高温电阻炉对转底炉直接还原红土镍矿新工艺进行热态模拟实验研究.通过正交实验考察了焙烧温度、焙烧时间,w(C)/w(O)三个因素对红土镍矿选择性还原的影响,并分析了考察因素对金属化率的影响程度,得出最优实验方案.结果表明,红土镍矿含碳球团转底炉工艺因素对金属化率影响程度依次为:w(C)/w(O)>焙烧温度>焙烧时间.当w(C)/w(O)到0.8时,铁金属化率最大为67.85%,此时XRD分析已检测不到镍氧化物的存在. 相似文献
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采用转底炉-电炉流程的还原-熔分工艺处理硼铁矿,制备金属化球团并进行熔分,产出生铁。通过单因素实验探索此工艺对处理硼铁矿的影响,研究并找出最佳工艺参数:焙烧时间21 min、焙烧温度1 250℃、n(C)/n(O)=1.2、熔分温度1 500℃、熔分时间30 min。采用XRD对硼铁矿最佳工艺参数下得出金属化球团分析可得:硼铁矿物相主要组成为硼镁石、磁铁矿、尖晶石、蛇纹石、硼镁铁矿石;经过焙烧还原后,赋存于磁铁矿、尖晶石、硼镁铁矿石中的铁基本被还原成金属态铁。 相似文献
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对某铝厂的拜耳法赤泥进行XRF-荧光、粒度、化学分析可知,赤泥中铁质量分数为31.42%,粒径在0.043 mm以下的占85.19%,是良好的铁资源。实验室条件下着重讨论了添加剂用量、w(C)/w(O)、还原温度、还原时间对还原后球团的金属化率和铁回收率的影响,获得最佳实验条件:添加剂用量10%,w(C)/w(O)=2.0,还原温度1 250℃,还原时间30 min,金属化率可达89.09%,磨选所得金属铁粉铁回收率83.91%,为赤泥在资源化提供一条解决途径。 相似文献
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Mathematical model of direct reduction in multilayer pellets made of metallurgical dust in a rotary hearth furnace
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A mathematical model of direct reduction of metallurgical dust pellet layers has been established in a rotary hearth furnace. The effects of radiation shielding of the upper layer to lower layer and the heating effects of the hearth were considered in the model. The control equations of the model were discretized into algebraic equations based on the control volume integration method and numerically solved by the alternating direction implicit method. The effects of pellet arrangement, furnace temperature, and the height of the pellet layer were investigated by the model. The results show that staggered arrangement of metallurgical dust pellets can improve average temperature of pellet layer. Thus, the degree of metallization and zinc removal rate of the pellet layer are improved. With the increase of furnace temperature, degree of metallization increases rapidly. Compared with iron oxide reductions, furnace temperature has less effect on zinc removal rate. With the height of pellet bed increasing to four layers, both degree of metallization and zinc removal rate of the fourth layer are slightly higher than that of the third layer. After heating for 15 min, extending heating time has little influence on zinc removal rate of each layer. 相似文献
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转底炉直接还原技术对钢铁行业资源综合利用的意义及发展前景分析 总被引:2,自引:0,他引:2
本文对我国钢铁行业贫矿资源和冶金尘泥的利用现状进行了分析,认为通过技术创新充分利用储量丰富的低品位铁矿资源和现有钢铁生产流程中难以处理的冶金尘泥,对提高行业资源综合利用水平、大力发展循环经济和推动节能减排具有重要意义。同时对当前处理这些资源的主要技术进行了分析和比较,提出应大力发展转底炉直接还原技术的重要结论,并对该技术的发展前景进行了预测。 相似文献
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焙烧几乎是所有固体催化剂及其载体制备的最后环节。焙烧温度对催化剂的结构性质、物相、晶粒大小、表面酸性以及强度、比表面、孔分布等性质具有重要影响,并最终影响催化剂的综合性能。从实验室少量焙烧到大批量的工业生产,即从小容积、温度场均匀、浓度场均匀和间歇操作的实验室焙烧装置放大到温度场和浓度场尚不十分清晰的工业焙烧设备,有必要研究设备变化的工业放大效应。在催化剂工业生产中,有微波焙烧炉、厢式焙烧炉、回转式焙烧炉、网带式焙烧炉、流态化焙烧炉、立式焙烧炉、隧道窑、梭式窑、辊道窑等多种焙烧窑炉可供选择。厢式炉不适于连续生产,网带式炉不适于高温焙烧,对于大批量催化剂的高温焙烧往往采用隧道窑和连续式回转炉。通过炉体自身的旋转,回转炉能促使物料颗粒之间的相互混合,而隧道窑则不能;回转炉炉体不漏风,物料床层截面主体温度均匀,而隧道窑中易出现窑车下部漏风、窑车自身蓄热等问题,从而引起预热段断面的上下温差;此外,隧道窑温度分布不均匀。微波炉具有加热速度快等优点,是近年来发展较快的焙烧方式。 相似文献
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Hanquan Zhang Zeqiang Zhang Hong Yu 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(1):47-64
Fe–P separation and the behaviors of Fe and P in separation process of high-phosphorus oolitic hematite ore from western Hubei province in China were studied. Various parameters, including reducing temperature and time, dosage of the pulverized coal, grinding fineness of magnetic separation feed, magnetic field intensity and grinding fineness of flotation feed were investigated. Experimental results show that the iron concentrate with total iron grade of 61.78% and phosphorus content of 0.23% was obtained from an oolitic hematite ore containing 47.71% iron and 0.874% phosphorus by magnetization roasting-magnetic separation-reverse flotation separation process under the proper conditions. In the magnetization roasting process, the Fe and P grade was rising by 1.30% and 11.49%, respectively; the forms of Fe and P are oolite hematite (magnetite) and collophanite which mainly distributed inside oolite structure and a small portion being distributed in other shapes. In the magnetic separation process, the Fe is from 48.33% to 58.52%, and P grade was slipped to 0.70% from 0.97%, however, the forms of Fe and P have no change compared with the roasted ore. In the reverse flotation separation process, Fe is from 58.52% to 61.78%, phosphorus is from 0.70% to 0.23%, the flotation concentrate mainly contained fine iron mineral and phosphorus is finely disseminated inside the iron mineral. 相似文献
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