Reduction of Titanium Oxide and Thickening of Blast Furnace Slag Bearing Higher Titania

The slag samples that have some titanium oxide reduction grade are reduced with blast furnace slag taken from Pan Zhi Hua Iron & Steel (Group) Co. in site. Then the viscosity and free running temperature of slag samples were measured in laboratory. With the increasing of reduction grade the viscosity and free running temperature of slags would have rising tendency. The mineral structure of the samples is observed in optical microscope, and quantitative analysis of TiC, TiN in the slag samples is made with image analysiser. The results show that the thickening of titanium slag has relationship with the amount of TiC, TiN, which was reduced from titania. So the usage of titanium oxide reduction grade as the index of thickening in blast furnace process is reasonable, and which could represent characteristic of the blast furnace smelting iron ore bearing titanium and vanadium.     

Experiment of the Influence of Manganese Oxide on the Prosperities of High Alumina Content BF Slag

Alumina content in Nanjing Steel blast furnace slag is up to 19%, which results in worse slag fluidity, higher furnace operating temperature and higher silicon content of hot metal. Therefore blast furnace strengthening is reduced. Aiming at this problem, an by laboratory experiments the viscosity of simulating Nanjing Steel BF slag samples are measured after adding MnO, which are made up of analytically pure chemical reagents. And according to the experimental results, the influence of MnO on the properties of high alumina content BF slag is analyzed and the methods of reducing silicon content of hot metal in Nanjing Steel is educed. The results showed that the addition of MnO in high Al2O3 content slag has stronger effects on viscosity decreasing, and the decreasing of slag viscosity would make it possible to reduce the operating temperature of the blast furnace, which would result in decreasing of silicon content of hot metal.     

MgO对高铝高炉渣脱硫的影响及其动力学分析

随着廉价高铝铁矿石的不断使用,高炉炉渣内Al₂O₃含量也随之升高,这势必会影响高炉炉渣的各项冶金性能。为深入研究高铝高炉渣脱硫性能,明确MgO含量对高铝渣脱硫性能的影响,笔者通过改变高铝渣中MgO的含量,分别设定渣中MgO含量为5%、9%、13% MgO,研究不同MgO含量高炉高铝渣的脱硫性能及其脱硫动力学。结果表明：MgO含量不仅对高铝渣的黏度、脱硫能力有不同的影响,还使炉渣的脱硫速率发生了很大的改变。MgO含量越高对应的黏度越低,脱硫能力越大;但脱硫速率却表现出了不同规律,9% MgO的脱硫速率表现为最大;经过综合比较,当碱度固定为1.1、Al₂O₃含量固定为17%时,MgO含量为9%的炉渣同时具有较好的粘度和脱硫性能。     

Effect of UPC on the Dropping Property of Slag of BF at PANZHIHUA I & S CO.

A series of fundamental experiments are carried out to clarify UPC on the effect of taking shape and dropping of slag of BF at PANZHIHUA I & S CO. by using high temperature. oven simulation cohesive zone and dropping zone of blast furnace. The following results are obtained: The dropping quantity of the Titanium bearing Slag increases with UPC increasing. It is conclusion opposite to that of commonly blast furnace slag.     

A Study on Lightweight Aggregate Concrete with High Fluidity

In this paper, the influence of fly ash (FA), blast furnace slag (BS) and silica fume (SF) on the properties of lightweight aggregate concrete (LAC) with high fluidity were studied. Results show that in LAC the effects of composite additives are better than that of single additive. The slump of LAC with apparent density of 1 840 kg/m 3 could reach 267 mm and the spread 650 mm. The 28d strength is 28.8 MPa for LAC with 20% ground FA and 20% BS as additives and the shale ceramsite with bulk density of 503 kg/m 3 and crushing strength 3.1 MPa was used as aggregate. Physical properties of lightweight aggregate have significant effects on durability of the flowing LAC.     

Development in Research Rheological Characteristics of Non-newtonian Metallurgical Molten Slags

Most of the former study for metallurgical molten slags (MS) was on the assumption that MS is newtonian fluid, and show lots of limitation. For the reasons such as the existence of gas-liquid phase points, MS shows a property of non-newtonian fluid. For this reason, the advances in some areas are conducted, including the measurement method, the factors influencing the MS and the viscosity computed models, which is prepared for the further research of the physical-chemical properties of blast furnace slag bearing titania.     

Properties of Temperature Difference Self-power Adjusting Valve Used in Blast Furnace

Blast furnace campaign life has a great effect on technical and economical indexes of ironmaking production. Cooling condition and life-span of cooling apparatus have a great influence on campaign life of blast furnace. Owing to constant flux water supply used for blast furnace cooling at present, cooling intensity doesn't meet the demand of heat load in peak value, concurrently, cooling water supply lacks equilibrium and stability, which will cause burnout of cooling apparatus and diminution of blast furnace campaign life. So temperature difference self-power adjusting valve is introduced to make BF cooling apparatus change constant flux water supply mode to constant temperature difference water supply mode in order to satisfy the need of cooling intensity when heat load wis in peak value.Principle, structure ,properties and function of temperature difference self-power adjusting valve are explained. The flux in different temperature is measured.     

氧气高炉多流体数值模拟与分析

为研究不同氧气高炉操作流程及操作参数对高炉内部过程产生的影响,预测氧气高炉流程各参数的变化规律,基于多流体理论、冶金传输原理、冶金反应动力学与热力学理论以及计算流体力学建立了普通高炉多流体模型,并在此基础上修改边界条件及内部相关参数,建立氧气高炉多流体数学模型。通过建立的模型分别对普通高炉和气化炉氧气高炉(GF-FOBF)流程中的氧气高炉进行了模拟计算,得到两种工艺流程下高炉内温度场、浓度场和速度场等典型参数的分布情况。通过对计算结果的对比,分析了氧气高炉操作条件下炉内状态的主要特征和相对于普通高炉发生的变化,发现氧气高炉内部速度场、温度场均发生变化,特别是气相组分的均匀分布问题明显。本模型可为氧气高炉流程试验及流程开发提供参考。     

Study on Autogenous Relative Humidity Change and Autogenous Shrinkage of High-Performance Concrete

Autogenous relative humidity (ARH) reduction and autogenous shrinkage (AS) due to self-desiccation are common phenomena in high performance or high-strength concrete, which are the main reasons resulting in cracking of concrete at early ages. In this paper, the effects of the ratio of water to cementitious material (w/cm), paste volume content and the combined addition of silica fume (SF) and ground blast furnace slag (GBFS) on ARH change and AS of concrete due to self-desiccation were studied, and their relationship was discussed. The results indicate that the w/cm is a main factor affecting ARH change and AS of concrete. With the reduction of w/cm, ARH change and AS of concrete increases. The combined addition of SF and GBFS also augments these properties at later ages. There is significant linear correlation between ARH change and AS of concrete with different w/cm, paste volume content and the combined addition of SF and GBFS.     

DEM模拟解析二元混合颗粒粒径偏析分布规律

颗粒粒径偏析分布是高炉炉顶布料过程中不可避免的现象,易造成炉喉处局部料层的空隙度降低和压差升高,影响煤气流的均匀分布,继而间接影响炉况的顺行。通过DEM离散单元法模拟研究二元混合颗粒的偏析分布规律,同时,提出一个偏析指数T,用以表征粒径偏析分布的相对程度。研究结果表明：同一T值图中,相邻区域颗粒的T值相差越大,则该区域颗粒的粒径偏析程度越大;不同T值图中,所有相邻T值之差的平均绝对值越大,则颗粒堆积整体粒径偏析程度越为严重。     

Smelting AlMnSi alloy by Using High-bearing Manganese Slag

First smelting MnSi alloy by using high-bearing manganese slag of BF by electric smelting process in a 25 kVA arc furnace in lab has been introduced. In order to increase the content of manganese and silicon in MnSi alloy , a little amount of MgO is added into the slag and the lower alkalinity has been adapted. Then smelting AlMnSi alloy using MnSi alloy containing high silicon that obtained by experiments and waste Al with an induction furnace has been studied. The controlling of temperature is the key in smelting process. The high quality AlMnSi alloy has been obtained successfully,Which can be extensively used for the compound oxygen removal agent for making steel and the metal alloy additive.     

The Study on Smelting Ti-Si Ferroalloy by DC Electrothermal Process Using PISC Blast Furnace Titaniferous Slag

The new process for semiting Ti-Si ferroalloy using Panzhihua Iron & Steel Company (PISC) blast furnace titaniferous slag is introduced. The reduction and impoverishment law of TiO2 in slag and the effects of DC on smelting Ti-Si ferroalloy are studied when smelting Ti-Si ferroalloy by electrosilicothermal method,Ti-Si ferroalloy containing about 20% Ti can be produced by electrosilicothermal method. and Ti recovery rate is less than 60 %. And then, electrosilicoaluminothermal method is developed, by which Ti-Si ferroalloy containing Ti more than 30% and Si less than 35 % can be produced, and Ti recovery rate is higher than 80%. Ti-Si ferroalloy can replace TiFe martially in steelmaking,and residue slag can be used to make cement.     

Effect of B2O3 on the physico-chemical properties of mold slag used for high-Al steel

A new mold slag with low content SiO2 and high content Al2O3 is designed in order to avoid or alleviate the reaction between Al and SiO2 during the continuous casting of high-Al steel, the acidity of this slag is adjusted by adding B2O3, and the effect of B2O3 content on the fusion property, viscosity property and heat transfer characteristics through the mold slag film of the mold slag is analyzed. The results show that the fusion temperature, viscosity, viscous flow activation energy decrease and heat flux through the slag film increases with the increase of B2O3 content in the range of 4%~10%; temperature time transformation (TTT) diagrams move to longer incubation time with the increase of B2O3, while the crystallization speed of mold fluxes decreases; under this experiment condition, the precipitation of CaF2 crystals can be restrained by the increase of B2O3 content in the mold slag.     

Study on the Dearsenization of Hot Metal Using CaO Basis Fluxes

There is plenty of iron ore with arsenic in China. Because a proven dearsenization technique does not come into existence in now iron making and steel making processes and it is necessary for developing the dearsenization of hot metal technologics. A serial of dearsenization experiments are carried out on electric resistance heated furnace, it's found that arsenic in hot metal can be removed by CaO basis fluxes. X ray qualitative analysis of CaO basis slag after dearsenization revealed that the product of hot metal dearsenization with CaO slag is Ca 3As 2 and the dearsenization reaction is a reducing one. The thermodynamic conditions of dearsenization of hot metal using CaO basis fluxes are that the lower of oxygen fraction pressure of the system and [s] in hot metal, the higher of temperature of the system and basically of the slag, the dearsenization efficiency is better.     

Dynamical Idnetification for Blast Furnace Condition

The correlation dimension for the time series of blast furnace process varisble,such as blast volume, burden pressure drop and blast pressure etc.,have been estimated by using GP and modified GP algorithms.The predictublity analysis for the process variables have also been investigated.The results show that it is difficult to determine the chaotic attractor of blast furnace condition.It has been found that the predictablity for process variables can be used to niterpret and identity the precursor of biast furnace condition.     

Analysis on the viscosity of six different compound smelting reduction slag

In combination with Huimin high-phosphorus iron smelted by smelting reduction and HIsmelt ironmaking technologywhich have the advantages of high efficient dephosphorizationCaO-SiO2-Al2O3-MgO-FeO-P2O5 slags with basicity R (mass ratio of CaO to SiO2)ranging from 0.8 to 1.4Al2O3 ranging from 6.4% to 15.4%P2O5 ranging from 0 to 3% and the content of MgO and FeO fixed as 4% and 6% respectivelyare studied.The slags are synthesized by reagent grade.The mineral composition and microstructure of the slags are studied with scanning electron microscope and the effects of changes in the composition of smelting reduction slags on its viscosity are studied by RTW-10 melt comprehensive physical properties measuring apparatus.Results show that the mineral structure of slags are mainly composed of melilite(gehlenite and akermanite)which is characterized by square and thick skeleton form.The viscosity decreases with the increasing of the slag basicity at fixed P2O5 or Al2O3 mass fractionincreases with the increasing of Al2O3 mass fraction at fixed slag basicity or P2O5 mass fractionand increases with the increasing of P2O5 mass fraction at fixed slag basicity or Al2O3 mass fraction.     

Recent Research on Supervision Running State of the Tuyere and Raceway in Blast Furnace

The manipulators pay fully attention to the running state of raceway looked into tuyere peehole in blast furnace in its production process. And it is important for judgement and control the blast furnace. The pulverized coal feeding and burning cases can be supervised by peehole in tuyere. Temperature distribution can be studied by brightness and numerical simulation of pulverized coal combustion. The recent research of temperature examined and supervision technique of the tuyere and raceway in blast furnace are set forth at home and abroad. A method settling supervision and control the state of tuyere and raceway in blast furnace is put forward by coalescent numeric image process technique to numeric simulate two dimensional imaging technique.     

Mathematical Model of Oxygen Blast Furnace with Preheating Gas Injection into Upper Shaft

An One-dimensional mathematical model,based on oxygen blast furnace with preheating gas injection into upper shaft,has been developed to describe the variation of innerdiameter of blast furnace,13 chemical reactions,the heat losses through the furnace wall,the heatexchange and pressure losses between gas phase and solid phase.The characters of oxygen blastfurnace are discussed,The simulated results indicate that the tem perature of burden in creasesthroughout the upper shaft with the incrcasement of the flow and the temperature of preheating gasinjected,and that the effect of the heating-up of burden is not so large when the com positions ofpreheatin8 gas injeetion are changed.The model is contributed to obtain a deeper understanding ofthe oxygen blast furnace process.     

Viscosity Calculating Model of Iron-bath Smelting Reduction Slag

It is thought that the smelting reduction is one of the advanced technology for metallrugical industry. The constitutes and characters change continuously because the charging is loaded periodically. The influence of slag viscosity is important for smelting process. The foundation of viscosity calculating model is propitious to rapidly forcast the slag viscosity. The viscosity calculating model of melting slag is founded according to the ion theory and the characters of iron-bath smelting reduction slag, the calculating program is finished. The result indicates that the calculating value and the measuring value is approaching. This model can be applied to calculate or forecast the iron-bath smelting reduction slag viscosity.     

氧气高炉工艺研究进展及新炉型设计

从氧气高炉的数学模型、实验室实验以及工业试验角度系统分析了氧气高炉工艺的发展现状及趋势,同时讨论了氧气高炉炉型的设计依据。论述了氧气高炉的静态工艺模型研究需要计算合适的直接还原度和热空区温度,同时应考虑氧气高炉工况下生产率的变化、热损失的变化、风口煤粉的喷吹上限以及N₂的循环积累等问题。指出了多维动力学模型和多目标优化模型中尚需解决的问题,以及氧气高炉数学模型的主要发展方向。结合文献研究中的氧气高炉特点,从炉身高度设计、炉腹角和炉身角设计以及风口设计3方面综述了氧气高炉炉型设计的变化规律。