Influence of Coating Granulation Process on Iron Ore Sinter Quality and Productivity

For better blast furnace performance, there has always been a need for better quality raw materials like sinter, lump ore, and pellets. Among these raw materials the usage of sinter in blast furnace is at higher side compared to other iron bearing materials. As the quality of sinter product improves, its usage in blast furnaces also increases. Iron ore fines are the main source for sinter making. To improve the sinter properties it is necessary to provide good quality of iron ore fines. Due to depletion of high grade iron ore resources, goethite and limonitic ore content in iron ore fines is expected to increase gradually. Usually limonitic and goethite ore are associated with higher alumina and LOI. The conventional sintering process is one of the well established processes for high quality hematite ore. It does not fully respond to the low grade iron ore associated with goethite and limonite. This has led to deterioration in sinter properties and productivity. In recent years the improvement in the quasi‐particle structure with the granulation process is an effective method for improving sinter quality and productivity. To improve the sinter quality and productivity for low grade iron ore fines, different granulation processes like the conventional one, and other two advanced granulation processes like coke breeze, and flux & coke breeze coating granulation were studied in detail by conducting laboratory pot grate sintering experiments. From the test results it was found that sinter productivity, physical and metallurgical properties of the sinter improved with flux & coke breeze coating granulation process compared to conventional and coke breeze coating granulation process. Proper selection of the granulation time is very important to achieve the desired sinter properties. In the present work detailed laboratory experiments have been carried out by varying the coating time from 30s to 110s to study the influence of flux & coke breeze coating granulation time on mineralogy, productivity, physical, and metallurgical properties of sinter. With a coating granulation time of 50s, higher productivity, higher yield, and stronger sinter (higher T.I) with lower RDI and ‐5mm size sinter were achieved.     

The language of motivational interviewing and feedback: Counselor language, client language, and client drinking outcomes.

Previous research has suggested that motivational interviewing (MI) may affect client language, which in turn predicts client drinking outcome. In this study, we examined the relationship between counselor language and client language, personalized feedback and client language, and client language and client drinking outcome, in a sample of heavy-drinking college students. MI was delivered in a single session with or without a personalized feedback report (MI with feedback [MIF]; MI only). Sessions were coded using the Motivational Interviewing Skill Code 2.1. A composite drinking outcome score was used, consisting of drinks per week, peak blood alcohol concentration, and protective drinking strategies. We found three main results. First, in the MIF group, MI consistent counselor language was positively associated with client change talk. Second, after receiving feedback, MIF clients showed lower levels of sustain talk, relative to MI only clients. Finally, in the MIF group, clients with greater change talk showed improved drinking outcomes at 3 months, while clients with greater sustain talk showed poorer drinking outcomes. These results highlight the relationship between counselor MI skill and client change talk, and suggest an important role for feedback in the change process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reactive wetting of Sn–2.5Ag–0.5Cu solder on copper and silver coated copper substrates

In the present work, wetting characteristics and morphology of intermetallic compounds (IMCs) formed between Sn–2.5Ag–0.5Cu lead-free solder on copper (Cu) and silver (Ag) coated copper substrates were compared. It was found that, Ag coated Cu substrate improved the wettability of solder alloy. The average values of contact angles of solder alloy solidified on Ag coated Cu substrate were reduced to about 50 % as compared to contact angles obtained on Cu substrates. Flow restrictivity for spreading of solder on Ag coated Cu was found to be lower as compared to Cu substrate. The spreading of solder alloy on Ag coated Cu exhibited halo zone. Coarse needle shaped Cu₆Sn₅ IMCs were observed at the solder/Cu substrate interface whereas at the solder/Ag coated Cu interface Cu₆Sn₅ IMCs showed scallop morphology. The formation of Cu₃Sn IMC was observed for the spreading of solder alloy on both substrates. The solder/Ag coated Cu substrate interface exhibited more particulates of Ag₃Sn precipitates as compared to solder/Cu substrate interface. The improved wettability of solder alloy on Ag coated Cu substrate is due to the formation of scallop IMCs at the interface.     

Energy-aware manufacturing operations

This editorial introduces the special issue on energy-aware manufacturing operations in the International Journal of Production Research. The 12 papers in this special issue were selected because of their high quality and also because they deal with topics related to energy-aware manufacturing operations. Three broad challenges are collectively addressed by the papers in this special issue: energy-efficiency vs. manufacturing-system effectiveness in optimisation; the volatility in energy availability, supply and cost; modelling energy consumption in varying scales and across different sub-systems. Previous global discussions about the state of the art in energy-aware manufacturing operations are provided, as well as exploratory guidelines for future research in this area.     

Synthesis,growth and characterization of π conjugated organic nonlinear optical chalcone derivative

A new potentially useful nonlinear optical organic material, 1-(5-chlorothiophen-2-yl)-3-(2,3-dimethoxyphenyl)prop-2-en-1-one, has been synthesized and grown as a high-quality single crystal by the slow evaporation technique. The grown crystals were characterized by FT-IR, NMR, thermal analysis, and UV–visible spectroscopy. The material is thermally stabile up to 111 °C. The mechanical property of the grown crystals was studied using Vickers microhardness tester and the load dependence hardness was observed. The third order nonlinear optical properties of the material such as real and imaginary part of χ⁽³⁾, nonlinear absorption coefficient and nonlinear refractive index were determined using nanosecond laser pulses at 532 nm wavelength by employing Z-scan technique. The nonlinear refractive index is found to be of the order of 10⁻¹¹ cm² W⁻¹. The magnitude of third order susceptibility is of the order of 10⁻¹³ esu. The observed increase in the third order nonlinearity in these molecules clearly indicates the electronic origin. The compounds exhibit good optical limiting at 532 nm. The best optical limiting behavior of this molecule is due to the substituted strong electron donor.     

Casting/mould interfacial heat transfer during solidification in graphite,steel and graphite lined steel moulds

Heat flow between the casting and the mould during solidification of three commercially pure metals, in graphite, steel and graphite lined steel moulds, was assessed using an inverse modelling technique. The analysis yielded the interfacial heat flux (q), heat transfer coefficient (h) and the surface temperatures of the casting and the mould during solidification of the casting. The peak heat flux was incorporated as a dimensionless number and modeled as a function of the thermal diffusivities of the casting and the mould materials. Heat flux transients were normalised with respect to the peak heat flux and modeled as a function of time. The heat flux model proposed was used to estimate the heat flux transients during solidification in graphite lined copper composite moulds.     

Iron(III) Chloride‐Catalysed Aerobic Reduction of Olefins using Aqueous Hydrazine at Ambient Temperature

A chemoselective reduction of olefins and acetylenes is demonstrated by employing catalytic amounts of ferric chloride hexahydrate (FeCl₃⋅6 H₂O) and aqueous hydrazine (NH₂NH₂⋅H₂O) as hydrogen source at room temperature. The reduction is chemoselective and tolerates a variety of reducible functional groups. Unlike other metal‐catalysed reduction methods, the present method employs a minimum amount of aqueous hydrazine (1.5–2 equiv.). Also, the scope of this method is demonstrated in the synthesis of ibuprofen in aqueous medium.     

烧结工序中转炉渣的优化利用

钢铁厂产生的矿渣中很大一部分来自氧气顶吹转炉(LD转炉)和吹氧转炉工序.LD工序的主要目的是将熔融的铁水和废钢转化为优质钢.在印度,每年产生的熔融钢渣超过400～450万t.总体看来,生产每吨钢会产生150～200 kg的钢渣,对这些钢渣的处理已经成为了严重的环境问题.金达尔钢公司是年产700万t的联合钢厂,每天产生钢渣3 200 t,其中2 000～2 500 t来自LD转炉.LD转炉渣中含有47.75%的CaO,22.0%的Fe以及8.22%MgO,由于CaO含量很高,LD转炉渣可直接替代烧结工序中的生石灰.目前在实验室范围已进行了一些研究,以确定烧结工序中所允许的LD转炉渣的最大投加量以及转炉渣的投加对烧结产率和性能的影响.实验中,LD转炉渣在烧结矿里的添加量从0依次到60 kg/t.随着添加率的增大,烧结料层温度的降低致使FeO含量降低,而烧结配矿中烧损的降低以及由于避免了石灰石煅烧过程带来的的重量损失,使得烧结产率上升.与此同时,LD转炉渣中缺少自由的CaO,使烧结矿强度及还原粉化指数变差,可参加反应的CaO的减少也导致了铁酸钙相减少,及残存Fe2O3自由相增加.试验结果最终得出:烧结矿中LD转炉渣的投加量为30～35 kg/t时,可获得预期的烧结矿性能.