检索结果-南通市图书馆

Effect of alumina occurrence form on metallurgical properties of hematite and magnetite pellets

Journal of Iron and Steel Research International 2024年第4期31卷 797-809页

作者： Jian Pan Chen-mei Tang Cong-cong Yang de-qing zhu Zheng-qi Guo Wei-qun Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Exploration and development of Geology and Mineral Resources Co. Ltd.Nanchang 330030JiangxiChina

The effect of alumina occurrence form on the metallurgical properties of both hematite and magnetite pellets was investigated at the same Al_(2)O level of 2 wt.%,including reduction index(RI),low-temperature reduction disintegration index(RDI),reduction swelling index(RSI),and high-temperature softening-dripping *** mineralogy of fired pellets was also studied to reveal the influence of alumina occurrence form on the phase composition and *** the results,the alumina occurrence form presents tremendous impacts on the metallurgical perfor-mance of both magnetite and hematite *** of all alumina occurrence forms contributes to inferior reducibility of pellets,especially in the case of gibbsite for magnetite pellets with a RI of 58.4%and kaolinite for hematite pellets with a RI of 56.8%.However,addition of all alumina occurrence forms improves the RDI of magnetite pellets,while there is no significant difference among various alumina occurrence *** contrast,alumina occurrence forms have little influence on the RDI of hematite *** presence of free alumina,gibbsite,and kaolinite tends to improve the RSI of hematite and magnetite pellets,whereas hercynite gives the opposite trend with a RSI of 25.6%.For softening-dripping performance of magnetite pellets,all alumina occurrence forms contribute to narrower softening-melting ***,alumina,gibbsite,and kaolinite give narrower softening-dripping interval,at 229,217,and 88℃,respectively,whereas addition of hercynite results in the largest melting range at 276℃ due to its high melting *** hematite pellets,free alumina,gibbsite,and hercynite tend to enlarge melting range,whereas kaolinite contributes to lower dripping temperature of 1148℃ and narrow softening-dripping interval of 88℃ due to the formation of a greater amount of slag phase at high temperatures.

关键词： Oxidized pellet Magnetite Hematite Alumina occurrence form Metallurgical performance Blast furnace

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effective utilization of dolomitic lead-zinc waste rock by replacing dolomite as flux in iron ore sintering process

引用

Journal of Iron and Steel Research International 2024年第8期31卷 1861-1872页

作者： Xin Wang Cong-cong Yang Jian Pan de-qing zhu Zheng-qi Guo Guang-hui Xia Shi-juan Qu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Low-Carbon and Hydrogen Metallurgy Research Center Central South UniversityChangsha 410083HunanChina

With increasingly stringent environmental protection policies,cost-effective and value-added treatment of massive lead-zinc waste rock(LZWR)generated from the preconcentration process has attracted substantial attention.A type of dolomitic LZWR with 18 wt.%MgO,27 wt.%CaO,0.29 wt.%Zn and 1.43 wt.%S was used as a replacement flux in the iron ore sintering *** sinter pot tests were carried out based on an industrial ore *** results show that replacing 0%-60%of dolomite with LZWR does not adversely affect the sintering productivity,fuel consumption rate,and the quality of the sinter products,while the Zn and S elements contained in LZWR can be effectively removed with the residual Zn and S contents of the resultant sinter products being less than 0.02 and 0.055 wt.%,***,substituting LZWR for dolomite as a flux inevitably increases the SO_(2) concentration in the sintering flue gas due to its high sulfur *** the processing capacity of the sintering flue gas desulfurization system,the replacement ratio of dolomite can reach 40%,equal to LZWR consumption of 24.3 kg per ton of *** SO_(2) in sintering flue gas can be recovered to produce(NH_(4))_(2)SO_(4) or HSO_(4),while the volatilized Zn collected into the zinc-containing dust can be subsequently recycled by the rotary hearth furnace ***,it is technologically and economically feasible to use the LZWR as a replacement flux in the iron ore sintering process,providing a new way for the safe,large-scale and low-cost treatment of LZWR.

关键词： Lead Zinc waste rock Dolomite Sintering Flue gas Sinter product

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effects of Time delay on Multistability of Genetic Toggle Switch

引用

Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： de-qing zhu Hui-jun Jiang Zhong-huai Hou department of Chemical Physics & Hefei National Laboratory for Physical Sciences at the Microscales iChEM University of Science and Technology of China Hefei 230026 China

The effect of time delay on a genetic toggle switch, whose undelayed dynamics shows low protein expression states (L-states), high expression states (H-states) and coexistence of them different transcription-factor binding rates α, is investigated by using the delayed stochastic simulation method. Interestingly, we find that the delay induces a transition from the coexistence state to L-state or H-state by suppressing the other state. Moreover, the phase diagram on the α-τ plane is obtained by extensive simulations. It is observed that, the coexistence state is remarkably narrowed by increasing delay time, and completely disappears above a triple-point-like point where direct transitions between H-state and L-state are possible.

关键词： Genetic toggle switch delay Multistability

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Some basic properties of granules from ore blends consisting of ultrafine magnetite and hematite ores

引用

International Journal of Minerals,Metallurgy and Materials 2019年第8期26卷 953-962页

作者： Cong-cong Yang de-qing zhu Jian Pan Yue Shi School of Minerals Processing and Bioengineering Central South University

Some basic properties of granules,including the granule size distribution,packed-bed permeability,and chemical composition of the adhering layer,were investigated in this study for four iron ore blends consisting of 5wt%,25wt%,and 45wt%ultrafine magnetite and 25wt%ultrafine hematite *** effects of varying the sinter basicity(CaO/SiO2 mass ratio=1.4 to 2.2)and adding ultrafine concentrates on the variation of the adhering-layer composition and granule microstructure were ***,the effect of adhering-layer compositional changes on sintering reactions was discussed in combination with pot sintering results of ore *** sinter basicity led to an increase in the basicities of both the adhering layer and the fine part of the sinter mix,which were higher than the overall sinter *** the sinter chemistry was fixed and fine Si-bearing materials(e.g.,quartz sand)were used,increasing the amount of ultrafine ores in the ore blends tended to reduce the adhering-layer basicity and increase the SiO2 content in both the adhering layer and the fine part of the sinter mix,which will induce the formation of low-strength bonding phases and the deterioration of sinter *** adhering-layer composition in granules can be estimated in advance from the compositions of the-1 mm fractions of the raw materials.

关键词： iron ore granule adhering layer magnetite concentrate sinter basicity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Influence of Mechanical Activation on Acid Leaching dephosphorization of High-phosphorus Iron Ore Concentrates

引用

Journal of Iron and Steel Research International 2016年第7期23卷 661-668页

作者： de-qing zhu Hao WANG Jian PAN Cong-cong YANG School of Minerals Processing and Bioengineering Central South University

High pressure roll grinding（HPRG）and ball milling were compared to investigate the influence of mechanical activation on the acid leaching dephosphorization of a high-phosphorus iron ore concentrate,which was manufactured through magnetizing roasting-magnetic separation of high-phosphorus oolitic iron *** results indicated that when high-phosphorus iron ore concentrates containing 54.92 mass% iron and 0.76 mass% phosphorus were directly processed through acid leaching,iron ore concentrates containing 55.74mass%iron and 0.33mass%phosphorus with an iron recovery of 84.64%and dephosphorization of 63.79% were *** high-phosphorus iron ore concentrates activated by ball milling were processed by acid leaching,iron ore concentrates containing56.03mass%iron and 0.21mass% phosphorus with an iron recovery of 85.65% and dephosphorization of 77.49%were ***,when high-phosphorus iron ore concentrates activated by HPRG were processed by acid leaching,iron ore concentrates containing 58.02mass%iron and 0.10mass% phosphorus were obtained,with the iron recovery reaching 88.42% and the dephosphorization rate reaching 88.99%.Mechanistic studies demonstrated that ball milling can reduce the particle size,demonstrating aprominent reunion *** contrast,HPRG pretreatment contributes to the formation of more cracks within the particles and selective dissociation of iron and P bearing minerals,which can provide the favorable kinetic conditions to accelerate the solid-liquid reaction *** such,the crystal structure is destroyed and the surface energy of mineral particles is strengthened by mechanical activation,further strengthening the dephosphorization.

关键词： high-phosphorus iron ore concentrate high pressure roll grinding ball milling selective dissociation sulfuric acid leaching dephosphorization iron recovery

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Insights on pretreatment of Indian hematite fines in grate-kiln pelletizing process： the choice of grinding processes

引用

Journal of Iron and Steel Research International 2018年第5期25卷 506-514页

作者： de-qing zhu Zheng-qi Guo Jian Pan Zhao-yuan Wang School of Minerals Processing and Bioengineering CentralSouth University Changsha 410083 Hunan China Engineering design and Research Institute Northern HeavyIndustries Group Shenyang 110141 Liaoning China

Indian hematite fines are normally characterized by high iron grade and minor impurities, which are usually used for sinter fines. With macroscale operations technology of blast furnace in Indian, pellets, as a kind of high-quality materials, attract more and more attention. However, the hematite fines possess the coarse size. Hence, they inevitably need to be further finely ground for pelletizing before balling. The grinding behavior of Indian hematite fines was revealed by conducting the ball milling tests and determining the Bond ball mill work index （Wi）. The results show that Indian hematite fines have an excellent grindability with Wi of only 7.40-7.73 kWh/t, indicating that ball milling is an economically viable way to pretreat Indian hematite fines. Nonetheless, due to poor sedimentation and filtering properties of wet ground products, the dry ball milling is more appropriate to process Indian hematite fines. In addition, the superior quality green balls can be manufactured with dry ground products under the conditions of 0.5% bentonite dosage, 7.5% moisture and balling for 12 min, which further confirmed that the recommended pellet feed preparation technique is reasonable.

关键词： Indian hematite fine · Dry ball milling · Wet ball milling · Bond work index · Sedimentation characteristic ·Filtration characteristic

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Grate-kiln pelletization of Indian hematite fines and its industrial practice

引用

International Journal of Minerals,Metallurgy and Materials 2017年第5期24卷 473-485页

作者： de-qing zhu Feng Zhang Zheng-qi Guo Jian Pan Wei Yu School of Minerals Processing and Bioengineering Central South University Institution of Resources Strategy Wuhan Iron and Steel Corporation

Indian hematite fines normally have a high iron grade and minor impurities; they are usually used as sinter fines for feeding into a blast furnace. In this work, the grindability properties of two kinds of Indian hematite fines and the roasting behaviors and induration characteristics of pellets made from these fines were revealed through experiments involving dry ball milling and small-scale and pilot-scale tests. In addition, the microstructures of the particles of ground India hematite fines and fired pellets were investigated using optical microscopy. On the basis of the results, a grate-kiln production line with an annual output of 1.2 Mt of oxidized pellets was established in India. This pellet plant operates stably and reliably, further confirming that preparing high-quality pellets with Indian hematite fines pretreated by dry ball milling is an industrially feasible process. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

关键词： Ball milling Blast furnaces Industrial management Kilns Milling (machining) Pelletizing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Improving roasting performance and consolidation of pellets made of ultrafine and super high grade magnetite concentrates by modifying basicity

引用

Journal of Iron and Steel Research International 2020年第7期27卷 770-781页

作者： Feng Zhang de-qing zhu Jian Pan Zheng-qi Guo Meng-jie Xu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Sinosteel Equipment&Engineering Co. Ltd.Beijing 100000China

For improving the strength of pellets made of ultrafine and super-high-grade magnetite concentrates,the influence of basicity(CaO/SiO2 ratio)on the roasting and consolidation of pellets was *** results showed that with the basicity of pellets increasing from 0.09 to 0.60,the compressive strength of both preheated and roasted pellets achieved an evident improvement from 502 and 2519 to 549 and 3096 N/pellet,respectively;meanwhile,the roasting time decreased from 15 to *** low-viscosity liquid phases were easily generated in fired pellets at the basicity range of 0.40-0.60 under the roasting temperature of 1240℃,filled the voids between hematite particles and tightened the bonding among particles,effectively restraining the generation of concentric cracks and decreasing the porosity of fired pellets;low-viscosity liquid phases facilitated the solid diffusion of hematite,leading to the formation of coarse hematite crystals and thicker connecting necks.

关键词： Basicity Consolidation Ultrafine and super-high-grade magnetite concentrate Fired pellet Compressive strength Liquid phase

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Influence of basicity on metallurgical performances of fired super high-grade magnetite pellets in hydrogen-rich gases

引用

Journal of Iron and Steel Research International 2021年第10期28卷 1212-1222页

作者： Feng Zhang de-qing zhu Jian Pan Zheng-qi Guo Meng-jie Xu College of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina Sinosteel Equipment&Engineering Co. Ltd.Beijing100080China

The influence of basicity on the metallurgical performances and reduction characteristics of fired super high-grade magnetite pellets under the simulated shaft furnace gas conditions was *** fired pellets in the basicity range of 0.09(natural basicity)to 1.00 show superior reducibility and low-temperature disintegration ***,in the basicity range of 0.20–0.80,the abnormal swelling of the fired pellets *** basicity from 0.09 to 0.40 promotes the generation of low melting point slag phases and lower porosity of fired pellets,and accelerates the growth and densification of hematite crystals,impeding the reduction of hematite particles and the formation of metallic iron *** addition,the slags that distribute between the hematite particles absorb the reduction stresses by increased distances between the particles during the reduction process,which leads to the large reduction swelling of pellets.

关键词： Ultrafine high-grade magnetite concentrate Basicity Metallurgical performance Reduction behavior Gas-based shaft furnace direct reduction Fired pellet

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Oxidation and Induration Characteristics of Pellets Made from Western Australian Ultrafine Magnetite Concentrates and Its Utilization Strategy

引用

Journal of Iron and Steel Research International 2016年第9期23卷 924-932页

作者： Cong-cong YANG de-qing zhu Jian PAN Bin-zhi ZHOU Hu XUN department of Ferrous Metallurgy Central South University

Western Australian magnetite concentrates normally have ultrafine granularity and much higher specific surface areas than Chinese magnetite concentrates owing to the significant pre-grinding and beneficiation for saleable iron grade. Such characteristics will inevitably affect the subsequent pelletization process. However, very few investi- gations have been done before. Thus, the oxidation and induration characteristics of pellet made from a Western Aus- tralian ultrafine magnetite concentrate were revealed by conducting routine preheating-roasting tests in an electric tube furnace and investigating the microstructure of fired pellets under an optical microscope in comparison with that of pellets made from typical Chinese magnetite concentrate. The liquidus regions of CaO-SiO2-Fe2O3 and CaO-SiO2- Al2O3 ternary systems in air at various temperatures were calculated by FactSage software to explain the importance of liquid phase in the consolidation of fired pellets. The results show that pellet made from ultrafine magnetite con- centrate possesses better oxidability and preheating performance than that made from Chinese magnetite concentrate. However, it has inferior roasting performance, usually requiring conditions of roasting at 1280℃ for at least 30 rain to acquire sufficiently high compressive strength, which are attributed to higher temperature sensitivity caused by its smaller particle size and less formation of liquid phase because of low impurities like CaO and Al2O3 in raw materials. Correspondingly, its roasting performanee can be significantly improved by blending with Chinese magnetite concen- trates or increasing the pellet basicity （WCaO/WSiO2）. By comprehensive evaluation, blending with Chinese iron ore concentrates is an appropriate way to utilize Western Australia ultrafine magnetite concentrates.

关键词： oxidation induration characteristic ultrafine magnetite concentrate iron ore pellet metallurgical performance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：