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不同喷吹煤种对除尘灰中未燃煤粉影响 总被引:1,自引:0,他引:1
国内某钢厂一座高炉现阶段喷煤量为160 kg左右,对其使用晨旭煤做喷吹煤时和正赫煤做喷吹煤时的2个阶段的高炉除尘灰(重力除尘灰和布袋除尘灰)进行了研究。高炉的重力灰和布袋灰的粒度组成和分布表明:重力灰中粒径主要集中在10~110 μm,小于110 μm颗粒占96%左右, 大于74 μm,小于297 μm的颗粒约占60%;布袋灰的粒度分布图大致集中在3~30 μm,小于20 μm颗粒占到80%以上。通过岩相显微分析得到了重力灰和布袋灰中的各显微组分的面积比,并根据除尘灰中未燃煤粉和焦粉的消耗程度,结合化学分析和岩相显微分析结果计算,得到了该高炉喷吹不同煤种时除尘灰中未燃煤粉所占的百分比。最后,初步得出喷吹不同煤种对高炉除尘灰中未燃煤粉质量分数的影响,即与晨旭煤相比,正赫煤的反应性和燃烧性都较好,喷吹期间,炉尘中产生的未燃煤粉较少,煤粉利用率较高。同时也表明,实验室热重法测得的燃烧性和反应性可以作为评价煤粉最终利用率的2个重要参数,为钢厂实际生产中的喷煤评价和煤种选择提供了可靠的新方法。 相似文献
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高炉采用3级除尘后,其第2级的旋风灰中含有大量的含铁氧化物和碳,将其作为喷吹煤粉的添加剂从高炉风口喷入,可促进煤粉燃烧,达到高效利用旋风灰的目的。对首秦高炉除尘灰进行粒度和化学成分分析,发现旋风灰可以作为添加剂与煤粉进行混合喷吹。通过实验室测定不同含量旋风灰对煤粉燃烧性的影响,确定在富氧率为3%,添加旋风灰比例为6%时,可达到最佳的煤粉燃烧效果。首秦高炉的试验结果表明,喷煤时添加3%以下的旋风灰代替相应的煤粉,生产平稳,喷吹系统运转正常。高炉自产的旋风灰作为煤粉添加剂是可行的,可以带来较好的经济效益和社会效益。 相似文献
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1 绪言 高炉喷吹煤粉是使高炉操作趋向稳定、增加生产灵活性、扩大煤种使用范围的有效技术。为增大煤粉喷吹量,必须搞清楚煤粉喷吹量和煤粉粒度的极限,确定出最合理的喷吹技术。 过去关于煤粉空间燃烧实验的报告指出。煤粉的燃烧性比重油差。因此,高炉大量喷煤或者用大颗粒煤粉都是困难的。 但是,在有焦炭存在时煤粉燃烧实验表明,风口燃烧带煤粉的燃烧性要比预想的好。在实际的高炉操作中,荷兰和法国的喷煤量达到了130kg/tFe以上。英国的粗粉喷吹,其煤粉的平均 相似文献
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高炉中喷吹干熄焦除尘灰(工艺焦粉),不但可以降低生铁成本,在一定程度上也可以缓解适合高炉喷吹的无烟煤资源短缺的弊端,对环境保护也有积极的意义。对评价高炉喷吹用燃料的各项可行性指标,如燃料的化学成分、燃烧性、着火点、爆炸性、发热值、反应性、可磨性等进行系统研究和分析。通过对干熄焦除尘灰代替部分高价无烟煤,有利于钢铁企业降低成本、提高废弃资源的利用率,也有利于节能减排,提供高炉喷吹技术指导。 相似文献
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为了充分掌握大喷煤条件下高炉喷吹不同燃料的可行性,对几种可用于鞍钢高炉喷吹的不同煤级煤种进行了深入研究,主要包括喷吹煤种的工业分析、元素分析,灰成分、发热量、可磨性、着火点和爆炸性、灰熔特性、燃烧性、反应性分析等。同时,结合动力学计算来表征不同煤种的化学反应特性差异。结果表明,随着煤级的升高,煤的软化温度逐渐提高,这主要和氧化钙的作用相关;提质煤和兰炭具有优异的燃烧和气化特性,并且其价格优势明显,安全爆炸性和可磨性符合高炉喷吹要求,搭配混合燃料进行高比例喷吹时有利于燃料结构优化和喷吹成本控制。 相似文献
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COREX喷煤燃烧利用的研究 总被引:2,自引:0,他引:2
喷吹的煤粉主要在回旋区内燃烧,COREX熔融气化炉的氧口回旋区较小,而回旋区空腔内氧气浓度高,燃烧带的理论燃烧温度高。采用数学模型计算了煤粉在氧口回旋区内的燃烧率。研究表明:当煤粉平均粒度为0.075mm,煤比不超过125kg/t时,煤粉在回旋区内的燃烧率可达65%以上。未燃煤粉将参与气化反应、直接还原和渗碳反应等过程。从这个角度分析,COREX熔融气化炉可接受的未燃煤粉量约为75kg/t;而在煤比为200kg/t时,COREX可接受的煤粉的燃烧率为60%左右。 相似文献
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Several approaches were chosen to simulate the combustion of carbon particles recycled in the melter gasifier of the COREX plant via a dust burner. Reaction rates from different literature sources were analysed to develop a functional reaction set for the carbon combustion. These models were tested in a 180° sector of the burner domain and were compared among each other. The results were transferred into a full 3D model of the dome region in the melter gasifier. 相似文献
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韩国浦项(POSCO)在COREX熔融还原工艺基础上,成功的开发了FINEX熔融还原炼铁工艺技术,并于2007年4月10日开工点火,设计产能150万妇,通过50天的验证,装置运行一切正常。FINEX工艺的基本原理是用四段流化床代替COREX装置的还原竖炉,流化床内还原气体和粉矿直接接触进行还原,还原后的热矿粉进入熔融气化炉。使用FINEX工艺,能够直接利用粒度小于8mm的粉矿,同时能够直接使用煤粉。COREX装置的熔融气化炉被用来对还原获得的海绵铁热压块进行最后还原和熔炼,也作为FINEX的煤气发生器,原来的还原竖炉用作为FINEX装置的贮料仓和加料仓。 相似文献
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LI Hai-feng LUO Zhi-guo ZOU Zong-shu SUN Jun-jie HAN Li-hao DI Zhan-xia 《钢铁研究学报(英文版)》2012,19(9):36-42
COREX process is one of the earliest industrialized smelting reduction ironmaking technology. A numerical simulation model based on discrete element method (DEM) has been developed to analyze the burden distribution in the melter gasifier of COREX process. The DEM considering the collisions between particles can directly reproduce the charging process. The burden trajectory, the location and the burden surface profile are analyzed in melter gasifier with a mixing charging of coal and direct reduction iron (DRI) at the same time. Considering the porosity of packed bed has an important effect on the gas flow distribution of melter gasifier, a method to calculate porosity has been proposed. The distribution of DRI and coal and the porosity in the radial direction are given under different charging patterns, which is necessary to judge the gas flow distribution and provide base data for further researching the melter gasifier for the next work in the future. The research results can be used to guide the operation of adjusting charging and provide important basis for optimizing the charging patterns in order to obtain the reasonable gas distribution. 相似文献
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休风时对COREX熔融气化炉进行风口取样,通过对风口试样的检测分析,用压差度的倒数表示炉内气相对料柱透液性的影响,用空隙度和温度强度的乘积表示炉内的渣铁液相对料柱透液性的影响,建立了表征熔融气化炉料柱透液性的公式.对两批风口试样的研究发现,熔融气化炉内不同位置风口试样的透液性指数与相应位置的滞留铁比呈现一致的对应关系.进一步分析了透液性指数的影响因素,发现在炉况不顺时,未反应完全的酸性脉石直接落入炉缸,导致沿风口径向部分位置的渣样熔化温度高于1500℃,影响了渣铁流动性.提出了增加料层厚度、采取合理的造渣制度、控制均匀的煤气流分布等技术措施,为改善熔融气化炉内料柱的透液性提供帮助. 相似文献
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《钢铁研究学报(英文版)》2015,(12)
Fuel consumption in the COREX-3000 process run in Baosteel is currently higher than the design index.Therefore,mass and heat balance equations for the COREX process were established using the basic principles included in the Rist operating diagram for blast furnace(BF)as a reference.Thermodynamic calculations were then used to modify the Rist operating diagram so that it was suitable for the COREX process.The modified Rist operating diagram was then applied for the evaluation of metallization rate(MR)and fuel structure to reduce the energy consumption in the COREX process.The modified Rist operating diagram for the shaft furnace(SF)provided a nearly ideal value for the restriction point W when the metallization rate was increased,while the point Pon the operating line for the melter gasifier(MG)moved upward due to reduction in the heat required in hearth.The feasibility of reducing the energy consumption during the COREX process by changing the fuel structure was also demonstrated. 相似文献
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Zhiguo Luo Yang You Haifeng Li Heng Zhou Zongshu Zou 《Metallurgical and Materials Transactions B》2018,49(4):1740-1749
Burden distribution plays an important role in achieving high stability and energy efficiency in the COREX melter gasifier. In this work, a 1/7.5 scale experimental apparatus is established to investigate the burden distribution under the independent and mixed charging conditions. The effects of GIMBAL distributor angle, rotational speed, DRI-flap angle, and charging pattern on these charging conditions are investigated. The results show that the non-uniform distribution of pellet in circumferential direction is intrinsic to the discharge system due to the shape of the DRI flap. The charging pattern has a significant impact on the ore-to-coal volume ratio and bed voidage. The ore-to-coal volume ratio reaches the peak at 550 to 650 mm, indicating that the reduction burden near the wall is heavier than that in the center. The voidage in the middle region is smaller than that of the center and near-wall region. The results also reveal the size segregation along the radial direction of the burden pile. The smaller particles tend to accumulate in the center while the larger ones segregate more near the wall. The findings obtained from experiments should be helpful for the efficient operation of the COREX melter gasifier. 相似文献
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A dynamic model of the COREX melter gasifier is developed to study the transient behavior of the furnace. The effect of pulse
disturbance and step disturbance on the process performance has been studied. This study shows that the effect of pulse disturbance
decays asymptotically. The step change brings the system to a new steady state after a delay of about 5 hours. The dynamic
behavior of the melter gasifier with respect to a shutdown/blow-on condition and the effect of tapping are also studied. The
results show that the time response of the melter gasifier is much less than that of a blast furnace. 相似文献
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Metallurgical and Materials Transactions B - In the current study, the thermochemical model of the COREX melter gasifier has been developed using the FactSage™ thermodynamic software, and... 相似文献