A Novel Sensing Imaging Equipment Under Extremely Dim Light for Blast Furnace Burden Surface:Starlight High-Temperature Industrial Endoscope

Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material charging control,optimize gas flow distribution and improve ironmaking efficiency.It has been challengeable to obtain high-quality optical burden surface images under high-temperature,high-dust,and extremelydim(less than 0.001 Lux)environment.Based on a novel endoscopic sensing detection idea,a reverse telephoto structure starlight imaging system with large field of view and large aperture is designed.Combined with a water-air dual cooling intelligent self-maintenance protection device and the imaging system,a starlight high-temperature industrial endoscope is developed to obtain clear optical burden surface images stably under the harsh environment.Based on an endoscope imaging area model,a material flow trajectory model and a gas-dust coupling distribution model,an optimal installation position and posture configuration method for the endoscope is proposed,which maximizes the effective imaging area and ensures large-area,safe and stable imaging of the device in a confined space.Industrial experiments and applications indicate that the proposed method obtains clear and reliable large-area optical burden surface images and reveals new BF conditions,providing key data support for green iron smelting.

Preparation and Properties of SiC Assembled Large Block for Blast Furnace Tuyeres

A SiC assembled large block for blast furnace tuyeres was prepared using silicon carbide particles(3-1 and 1-0.088 mm)and fine powder(<0.088 mm),silicon powder(<0.088 mm),industrial carbon black(N990),microsilica,ρ-Al_(2)O_(3) powder,etc.as raw materials.The developed block was compared with a silicon nitride bonded silicon carbide brick,a self-bonded silicon carbide brick and an imported self-bonded silicon carbide block to analyze and evaluate their service performance.The results show that:(1)in the 0-100 mm zone,the SiC large block mainly consists ofβ-SiC and nitrides such as O'-SiAlON,β-SiAlON,α-Si_(3)N_(4),and Si_(2)N_(2)O,the bulk density is 2.68-2.70 g·cm^(-3),the apparent porosity is 14%-15%,and the material structure is uniform;(2)in the 0-100 mm zone,β-SiC nano-whiskers intercalate with nitrides;with the depth increasing,the number of flocculentβ-SiC nano-whiskers increases,while the number of nitrides decreases;when the depth reaches 150 mm or more,the main bonding phases areβ-SiC and mullite;(3)compared with the reference products,the developed SiC large block has a good basic performance,and after alkali corrosion,the mass change rate is-0.1%,which is obviously superior to the imported self-bonded silicon carbide and the homemade silicon nitride bonded silicon carbide materials.

Effect of Blast Furnace Sludge (BFS) Characteristics on Suitable Recycling Process Determining

The present study aims to give a detailed characterization of blast furnace sludge (BFS) by using different techniques, in order to determine the most effective recycling method to recover valuable metals from this waste. BFS is composed mainly of hematite, as its iron-bearing phase, and carbon, in addition to fractions of silicate and carbonate materials. The studied BFS shows relatively high contents of iron (Fe) (390 g.kg-1), and carbon (C) (290 g.kg-1), due to abundance of hematite and coke, while the concentration of zinc (Zn) (2.5 g.kg-1) is low. The XRD analyses indicated that, hematite is more concentrated in the fine fraction (<20 μm), while the coarser fraction (90 - 250 μm) is dominated by calcite, quartz and X-ray amorphous coke. SEM-EDX analyses confirmed that particles rich in iron and zinc were detected in the fine fraction (<20 μm) of the sludge. Due to high Fe and C content in BFS, it can be utilized as self-reducing material and briquetting represent a potential method for recycling of blast furnace sludge.

Status and development of mineral wool made from molten blast furnace slag

This study describes the characteristics of mineral wool and its applications,and also introduces the traditional process of mineral wool made from molten blast furnace （BF） slag. Compared with high energy consumption of the traditional process,the production of mineral wool by using molten BF slag will be able to take full advantage of the sensible heat of molten slag, and also reduce production costs. However, there are also further issues to resolve such as how to obtain the required amount of molten BF slag and how to make it homogeneous. Based on the physical and chemical properties of the molten BF slag,the investigation into the relationship between temperature and viscosity under different acidity coefficients of the slag and silicon mixture was conducted. Combined with the crystallization and phase diagram of slag wool, its heat resistance, water resistance, durability and corrosion resistance were analyzed. Finally, trends of the technology development are proposed.

Mechanisms of phosphate removal from aqueous solution by blast furnace slag and steel furnace slag

We report the adsorption of phosphate and discuss the mechanisms of phosphate removal from aqueous solution by burst furnace slag (BFS) and steel furnace slag (SFS). The results show that the adsorption of phosphate on the slag was rapid and the majority of adsorption was completed in 5~10 min. The adsorption capacity of phosphate by the slag was reduced dramatically by acid treatment. The relative contribution of adsorption to the total removal of phosphate was 26%~28%. Phosphate adsorption on BFS and SFS follows the Freundlich isotherm, with the related constants of k 6.372 and 1/n 1.739 for BFS, and of k 1.705 and 1/n 1.718 for SFS. The pH and Ca2+ concentration were decreased with the addition of phosphate, suggesting the formation of calcium phosphate precipitation. At pH 2.93 and 6.93, phosphate was desorbed by about 36%~43% and 9%~11%, respectively. These results indicate that the P adsorption on the slag is not completely reversible and that the bond between the slag particles and adsorbed phosphate is strong. The X-ray diffraction (XRD) patterns of BFS and SFS before and after phosphate adsorption verify the formation of phosphate salts (CaHPO4·2H2O) after adsorption process. We conclude that the removal of phosphate by BFS and SFS is related to the formation of phosphate calcium precipitation and the adsorption on hydroxylated oxides. The results show that BFS and SFS removed phosphate nearly 100%, indicating they are promising adsorbents for the phosphate removal in wastewater treatment and pollution control.

Quantificational indexes for design and evaluation of copper staves for blast furnaces

The quantificational and normative design is the precondition of improving the design of copper staves for blast furnaces. Based on a 3-dimensional temperature field calculation model, from the view point of heat transfer and long campaigns note with the core of forming accretion, the forming-accretion-ability （FAA） and the rib hot surface maximum temperature difference （ATmax） as quantificational indexes to direct and evaluate the design of copper staves for blast furnaces were presented. The application of the two indexes in design essentially embodies the new long campaigns in the stage of design. With the application of the two indexes, good results can be obtained. Firstly, it was suggested that the rib height of a copper stave can be reduced to 15 mm, which is a new method and theory for the reduction of copper staves. Secondly, the influence of insert on FAA and ATmax, is decided by the volume of insert. According to this, the principle of design for the hot surface geometry of copper staves was put forward that the ratio of the rib hot surface to the copper stave hot surface （abbreviated as the ratio of rib to stave） must be maintained in the range of 45% to 55%; for the present copper stave with a 35-40 mm thick rib, the ratio of rib to stave in the range of 50% to 55% can optimize the design of copper staves; for the copper stave with a smaller rib thickness, for example 15 ram, the ratio of rib to stave in the range of 45% to 50% can optimize the design of copper staves. It can be summarized that the thicker the rib thickness, the larger is the ratio of rib to stave. 2008 University of Science and Technology Beijing. All rights reserved.

Dust Distribution Study at the Blast Furnace Top Based on k-Sε-u_(p)Model

The dust distribution law acting at the top of a blast fumace(BF)is of great significance for understanding gas flow distribution and mitigating the negative influence of dust particles on the accuracy and service life of detection equipment.The harsh environment inside a BF makes it difficult to describe the dust disthibution.This paper adresses this problem by proposing a dust distribution k-Sε-u_(p)model based on interphase(gas-powder)coupling.The proposed model is coupled with a k-Sεmodel(which describes gas flow movement)and a u_(p)model(which depicts dust movement).First,the kinetic energy equation and turbulent dissipation rate equation in the k-Sεmodel are established based on the modeling theory and single Green-function two scale direct interaction approximation(SGF-TSDIA)theory.Second,a dust particle mnovement u_(p)model is built based on a force analysis of the dust and Newton's laws of motion.Finally,a coupling factor that descibes the interphase interaction is proposed,and the k-Sε-u_(p)model,with clear physical meaning.ligorous mathematical logic,and adequate generality,is dleveloped.Siumulation results and o-site verification show that the k-Sε-u_(p)model not only has high precision,but also reveals the aggregate distribution features of the dust,which are helpful in optimizing the installation position of the detection equipment and imnproving its accuracy and service life.

Uses of Blast Furnace Slag as Complex Fertilizer

Significant quantities of slag are generated as waste material or by-product every day from steel industries. They usually contain considerable quantities of valuable metals and materials. Transforming these solid wastes from one form to another to be reused either by the same production unit or by different industrial installation is very much essential not only for conserving metals and mineral resources but also for protecting the environment. The sustainable development concept requires a more efficient management of waste materials and preservation of environment. The paper presents the basic characteristics of slag, analyses and it＇s modification by incorporating some essential plant nutrients and the possibility of its application as fertilizer was studied.

Study on the stability control technology of large-scaled blast furnaces

Nowadays,there are two major trends,which are the increasing blast furnace （BF） working volume and the decreasing fuel resource as well as the decline in its quality,in the ironmaking filed. The two trends lead to the difficulty in the BF operation. The decline of the BF stability requires higher and more elaborate operational techniques. A reasonable and compatible BF comprehensive operating system,as the base of the BF stabilization,is desired to satisfy the demand of large-scaled BF developments. Based on the practical operation of Baosteel No. 3 BF in 2010, the present work analyzes and discusses the basic rules of large-scaled BF stable control techniques,and further optimizes and improves its gas flow control techniques, develops strategies against the decline in fuel quality, which will contribute to the promotion of largescaled BF operational techniques progress.

基于料面视频图像分析的高炉异常状态智能感知与识别

智能感知、精准识别高炉(Blast furnace,BF)异常状态对高炉调控优化和稳定运行至关重要,但高炉内部的黑箱状态致使传统检测方法难以直接感知并准确识别多种高炉异常状态.新型工业内窥镜可获取大量料面视频图像,为直接观测炉内运行状态提供了全新的手段.基于此,提出一种基于料面视频图像分析的高炉异常状态智能感知与识别方法.首先,提出基于多尺度纹理模糊C均值(Multi-scale texture fuzzy C-means,MST-FCM)聚类的高温煤气流区域提取方法,准确获取煤气流图像,并提取煤气流图像多元特征;其次,提出基于特征编码的高维特征降维方法,结合自适应K-means++算法,实现煤气流异常状态的粗粒度感知;在此基础上,通过改进雅可比−傅立叶矩(Jacobi-Fourier moments,JFM)提取煤气流图像深层特征变化趋势,进而提出细粒度煤气流异常状态感知方法;最后,基于煤气流异常状态感知结果,结合料面视频图像,提出多级残差通道注意力模块(Multi-level residual channel attention module,MRCAM),建立高炉异常状态识别模型ResVGGNet,实现高炉煤气流异常、塌料和悬料的精准在线识别.实验结果表明,所提方法能准确识别不同的高炉异常状态且识别速度快,可为高炉平稳运行提供重要保障.

3BF控制冷却壁热负荷的实践

控制合适的高炉冷却壁热负荷对高炉操作和长寿起着至关重要的作用。

掺加BFS的乳化沥青冷再生混合料路用性能研究

为验证在乳化沥青冷再生混合料中掺加高炉矿渣(blast furnace slag, BFS)的可行性并分析掺加BFS的乳化沥青冷再生混合料的路用性能,采用直接掺加BFS和以消石灰做激发剂掺加BFS两种方案,与掺加1.5%水泥的冷再生技术方案进行对比试验。通过测试干湿劈裂强度、冻融劈裂强度、60℃动稳定度和60℃抗剪强度、单轴压缩等性能指标,最终确定了v用于乳化沥青冷再生混合料的合理利用方式。研究结果表明:干湿劈裂强度试验无法有效地反映乳化沥青冷再生混合料水稳定性差异;冻融劈裂强度试验能有效地评价其水稳定性。在乳化沥青冷再生混合料中用BFS直接替代水泥会降低混合料的水稳定性;采用1.5%BFS+0.3%消石灰激发剂后,可使混合料具备与掺加1.5%水泥基本相当的路用性能。

Mechanism of phase separation in BFS (blast furnace slag) glass phase

XRD,TEM,ED,and NMR analyzed four types of blast furnace slags (BFS) with different structures in this paper. The composition requirement for phase separation in BFS glass phase was then put forward,that is the composition of slag locates in the coexisting phase region of melilite and any silicate mineral with Q0 units. The special structure of melilite units,a 5-membered ring with high degree of polymerization (DOP),plays a key role in the formation of phase separation. In BFS system,one with chemical composition of larger ratio of (CaO + MgO/(SiO2 + Al2O3) would be more promising to meet the requirement for phase separation.

高炉炉缸砌体结构及烘炉风量对炉缸长寿的影响简析

从高炉炉缸砌体结构和烘炉风量两个方面分析了对炉缸长寿的影响。认为:①稳定性相对较差的炉缸砌体结构,会因“象脚区”的侵蚀而导致侧壁炭砖加速出现大量的砖缝,继而出现“钻铁”情况,会大大缩短炉缸的寿命,建议采用整体稳定性更好的圆筒型炉缸结构。②高炉烘炉时,应关注烘炉的总风量能否将耐材中的水分完全带走,以减少水分及气隙对高炉长寿的影响,对于4000m^(3)以上高炉,单位炉容烘炉风量应达到10000m^(3)/m^(3)以上。

高炉渣均质化行为及其粒化效果研究

利用动态黏度实验法研究了高炉渣的均质化行为,构建熔渣调质过程动力学模型,同时对高炉渣均质化状态进行验证,并对最终粒化效果进行了分析。结果表明,均质化时间随调质剂添加量增加先减少后增加,添加量为15.43%时均质化时间最短;高炉渣粒度大于1.75 mm时,均质化时间明显增加;随炉渣温度升高,均质化时间逐渐缩短,通过与充分均质化高炉渣的成分及矿相进行对比,验证了高炉渣在黏度值达到稳定时已完成了均质化。粒化渣珠粒径主要位于1~2.5 mm,基本呈正态分布;高炉渣均质化处理后非晶相含量均高于85%,满足国家标准要求。

高炉大喷煤时煤粉利用率的研究

根据岩相显微分析和化学分析的结果,计算了宝钢高炉不同煤比操作条件下,炉尘中未消耗煤粉中的碳含量。给出了在正常生产情况下,炉尘碳含量与未消耗煤粉碳含量的关系式。确定了高炉喷煤比与炉尘碳含量和未消耗煤粉碳含量与喷煤比的关系式,进而计算了宝钢高炉在不同喷煤条件下煤粉在高炉内的利用率。为高炉大喷煤提供了必要的分析手段。

大掺量矿渣水泥砂浆碳化过程研究

矿物掺合料的引入会减少水泥砂浆内部碱性物质含量,同时其中的活性成分与氢氧化钙发生二次水化反应,进一步地减少了砂浆的碱性,从而降低了砂浆的抗碳化能力。本文通过热重-差示扫描量热试验研究了不同掺量粒化高炉矿渣引入对碳化产物和微观结构的影响。研究结果表明:喷洒酚酞指示剂显示为无色的碳化表层仍然存在少量的Ca(OH)2,这说明砂浆碳化存在部分碳化区;碳化反应物不仅包含Ca(OH)2,也包含水化硅酸钙凝胶(CSH gel),钙矾石(AFt),低硫型水化硫铝酸钙(AFm),硅酸二钙(C2S),硅酸三钙(C3S)等物质;此外,随着矿渣含量的提高,碳化速率增大,同时由于矿渣可以改善水泥浆体的孔结构,矿渣掺量在50%时,碳化速率最小。

高炉风口风量分配数学模型

建立了高炉风口风量分配数学模型,并提出风口流阻的计算公式.在总风量不变的条件下,计算了某5 500 m3高炉风口长度或者风口面积调整时,各风口风量、风速和鼓风动能的变化.结果表明增加风口长度或减小风口面积都将导致对应风口流阻增加.增加部分风口的长度,已调整的风口的风量、风速和鼓风动能降低.缩小部分风口面积,已调整的风口的风量降低;当缩小多个风口面积时,已调整的风口的风速、鼓风动能才能提高,并提出了其临界风口个数的计算公式.根据该数学模型,有利于掌握风口鼓风参数的变化规律,定量化调整风口的相关参数,维持高炉的稳定和顺行.

复合矿物掺合料混凝土力学性能的试验研究

对掺加不同矿物掺合料的混凝土在不同龄期下的力学性能进行了试验研究,研究了掺合料品种和掺量对混凝土力学性能的影响。试验结果表明:矿粉、粉煤灰和硅灰等矿物掺合料的掺入对混凝土性能有一定的影响,但其作用未必为正效应。在单掺情况下,矿渣和硅灰能有效地提高拌合物的黏聚性,从而改善混凝土强度,但对拌合物流动性有一定影响;掺加粉煤灰能有效提高混凝土的流动性,但产生泌水对拌合物匀质性有不良影响,而且由于粉煤灰的火山灰反应在常温下进行比较缓慢,因此混凝土早期强度较低。在双掺及三掺的情况下,复合矿物掺合料在混凝土中可发生火山灰复合效应、微集料复合效应等交互作用,混凝土强度较单掺有较大提高,由此得出复合矿物掺合料为配制优质混凝土的最佳途径。

基于熵权-可拓理论的高炉软熔带位置状态模糊综合评判方法

针对高炉(Blast furnace,BF)软熔带位置状态影响因素复杂多样且具有层次性和模糊性的特点,提出了基于熵权–可拓理论的高炉软熔带位置状态两级模糊综合评判的新方法.首先,在对高炉生产过程参数进行整理、分类的基础上,采用可拓理论和熵权法确定第一级评判的隶属矩阵和模糊权向量,进行一级模糊评判.其次,以一级评判结果矩阵构成第二级评判的隶属矩阵,并结合层次分析法(Analytic hierarchy process,AHP)确定的第二级模糊权向量,进行二级模糊评判.利用物元的可拓性定性分析和可拓集合论的关联函数定量计算相结合的方法,实现对高炉软熔带位置状态的两级模糊综合评判.最后,以某钢铁厂2 650 m3高炉为实例对其软熔带位置状态进行综合评判,所得结果与现场实际情况吻合良好.