Alkaline Leaching of Low Zinc Content Iron-Bearing Sludges

Various types of waste materials containing zinc (e.g. dusts and sludges from gas dedusting process) are obtained in steel industry. The contents of Zn in these materials may vary considerably. Even a low concentration of zinc in recirculated products precludes their recycling in ferrous metallurgy aggregates. Long storage of this type of material can lead to contamination of soil and water by zinc compounds which can be leached out by acid rain, for example. This paper focuses on research involving alkaline leaching tests of low zinc content iron-bearing materials. These tests were preceded by the analysis of the elemental, phase and grain size composition, and analysis of the thermodynamic conditions of the leaching process. The main aim of research was to decrease the content of the zinc in the sludge to the level where it is suitable as an iron-bearing material for iron production (~1% Zn). Leaching at elevated temperatures (368 K, 60 min) has led to a decrease in the zinc content in the sludge of about 66%. The research revealed that long hour leaching (298 K, 100 hours) carried out at ambient temperatures caused a reduction in zinc content by 60% to the value of 1.15-1.2% Zn.

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Technology and Mechanism of Valuable Metal Recovery from Pyrite Cinder by Chloridizing Roasting

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.588-589.1671 ◽

2012 ◽

Vol 588-589 ◽

pp. 1671-1676

Author(s):

Shao Jun Bai ◽

Shu Ming Wen ◽

Qi Cheng Feng ◽

Yu Chen ◽

Jian Liu

Keyword(s):

Steel Industry ◽

New Technology ◽

Metal Recovery ◽

Raw Material ◽

Pyrite Cinder ◽

Valuable Metal ◽

Zinc Compounds ◽

Lead And Zinc ◽

Chinese Steel Industry ◽

Iron Bearing

A new technology of pellet production-drying-chloridizing roasting is proposed for valuable metal recovery from pyrite cinder with high content of lead and zinc. The pyrite cinder, containing 60.15% Fe, 2.02% Pb and 2.15% Zn, was pelletized with addition of 2% bentonite in pan pelletizer. Green balls after drying were roasting at 1100 °C for 60 min with 5 wt % of CaCl2 addition in tube furnace. The results demonstrate that pellets with 61.58% of TFe, lead and zinc volatile ratios of 98.02% and 96.83% were obtained. Key technique is that CaCl2 reacts with lead and zinc compounds and the chloride can be volatilized at moderate temperatures. This new technology can recover the valuable metal fully from pyrite cinder and produce qualified concentrate as iron-bearing feed for steel industry, which will help to solve the pollution of pyrite cinder and extend raw material sourcing for Chinese steel industry.

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Optimization of Parameters of Blast Furnace Smelting Under Conditions of Plant Operation With Limited Supply of Coke, Natural Gas or Iron-Bearing Materials

AISTech 2021 Proceedings of the Iron and Steel Technology Conference ◽

10.33313/382/013 ◽

2021 ◽

Author(s):

M. Alter

Keyword(s):

Blast Furnace ◽

Natural Gas ◽

Blast Furnace Smelting ◽

Optimization Of Parameters ◽

Plant Operation ◽

Bearing Materials ◽

Limited Supply ◽

Iron Bearing ◽

Furnace Smelting

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Increasing Lump Ores Proportion in Blast Furnace Based on the High-temperature Interactivity of Iron Bearing Materials

ISIJ International ◽

10.2355/isijinternational.50.686 ◽

2010 ◽

Vol 50 (5) ◽

pp. 686-694 ◽

Cited By ~ 16

Author(s):

Shengli Wu ◽

Hongliang Han ◽

Haifa Xu ◽

Hongwei Wang ◽

Xiaoqin Liu

Keyword(s):

Blast Furnace ◽

High Temperature ◽

Bearing Materials ◽

Iron Bearing

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Comprehensive Utilization of Pyrite with High Content of Asrenic

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.524-527.965 ◽

2012 ◽

Vol 524-527 ◽

pp. 965-968 ◽

Cited By ~ 2

Author(s):

Dan Liu ◽

Shu Ming Wen ◽

Yong Jun Xian ◽

Hai Ying Shen ◽

Shao Jun Bai ◽

...

Keyword(s):

Sulfuric Acid ◽

Steel Industry ◽

Raw Material ◽

High Quality ◽

Comprehensive Utilization ◽

Roasting Temperature ◽

Chinese Steel Industry ◽

Iron Bearing

A technology of “arsenic removing- sulfuric acid producing- residuals for ironmaking” is proposed for comprehensive utilization of pyrite with high content of arsenic. The effect of roasting temperature and time on arsenic removing was investigated. The arsenic removed residuals obtained under the optimal arsenic removed conditions, was used to be proceeded for sulphur volatilization test. The results demonstrate that final residuals with 63.53% of Fe can be used for steel industry. This technology can be used to fully utilize sulphur and produce high quality concentrate as iron-bearing feed for steel industry, which will help to reduce the pollution of arsenic and extend raw material sourcing for Chinese steel industry.

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Characterization and regulation of cold-induced heat shock protein expression in mouse brown adipose tissue

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1995.269.1.r38 ◽

1995 ◽

Vol 269 (1) ◽

pp. R38-R47 ◽

Cited By ~ 15

Author(s):

J. M. Matz ◽

M. J. Blake ◽

H. M. Tatelman ◽

K. P. Lavoi ◽

N. J. Holbrook

Keyword(s):

Adipose Tissue ◽

Heat Shock ◽

Brown Adipose Tissue ◽

Cold Exposure ◽

Elevated Temperatures ◽

Uncoupling Protein ◽

Hsp70 Expression ◽

Mitochondrial Uncoupling ◽

Ambient Temperatures ◽

Brown Adipose

The accumulation of heat shock proteins (HSPs) after the exposure of cells or organisms to elevated temperatures is well established. It is also known that a variety of other environmental and cellular metabolic stressors can induce HSP synthesis. However, few studies have investigated the effect of cold temperature on HSP expression. Here we report that exposure of Institute of Cancer Research (ICR) mice to cold ambient temperatures results in a tissue-selective induction of HSPs in brown adipose tissue (BAT) coincident with the induction of mitochondrial uncoupling protein synthesis. Cold-induced HSP expression is associated with enhanced binding of heat shock transcription factors to DNA, similar to that which occurs after exposure of cells or tissues to heat and other metabolic stresses. Adrenergic receptor antagonists were found to block cold-induced HSP70 expression in BAT, whereas adrenergic agonists induced BAT HSP expression in the absence of cold exposure. These findings suggest that norepinephrine, released in response to cold exposure, induces HSP expression in BAT. Norepinephrine appears to initiate transcription of HSP genes after binding to BAT adrenergic receptors through, as yet, undetermined signal transduction pathways. Thermogenesis results from an increase in activity and synthesis of several metabolic enzymes in BAT of animals exposed to cold challenge. The concomitant increase in HSPs may function to facilitate the translocation and activity of the enzymes involved in this process.

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Screening of catalytic activity of natural iron-bearing materials towards the Catalytic Wet Peroxide Oxidation of Orange II

Journal of Environmental Chemical Engineering ◽

10.1016/j.jece.2018.03.001 ◽

2018 ◽

Vol 6 (2) ◽

pp. 2027-2040 ◽

Cited By ~ 4

Author(s):

Natalia Inchaurrondo ◽

Agustín Maestre ◽

Gregor Žerjav ◽

Albin Pintar ◽

Cinthia Ramos ◽

...

Keyword(s):

Catalytic Activity ◽

Orange Ii ◽

Peroxide Oxidation ◽

Wet Peroxide Oxidation ◽

Natural Iron ◽

Bearing Materials ◽

Catalytic Wet Peroxide Oxidation ◽

Iron Bearing

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Development of a New Technology for Converting Iron-Bearing Materials to Nodular Reduced Iron for Use in Various Steelmaking Operations

Innovative Process Development in Metallurgical Industry ◽

10.1007/978-3-319-21599-0_17 ◽

2016 ◽

pp. 327-358

Author(s):

Donald R. Fosnacht ◽

Iwao Iwasaki ◽

Richard F. Kiesel ◽

David J. Englund ◽

Rodney L. Bleifuss ◽

...

Keyword(s):

New Technology ◽

Bearing Materials ◽

Iron Bearing

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Temperature stability of oxytocin ampoules labelled for storage at 2°C–8°C and below 25°C: an observational assessment under controlled accelerated and temperature cycling conditions

BMJ Open ◽

10.1136/bmjopen-2019-029083 ◽

2019 ◽

Vol 9 (7) ◽

pp. e029083 ◽

Cited By ~ 3

Author(s):

Tri-Hung Nguyen ◽

Peter Lambert ◽

Rajpreet Singh Minhas ◽

Claire McEvoy ◽

Kim Deadman ◽

...

Keyword(s):

Elevated Temperatures ◽

Temperature Stability ◽

Global Market ◽

Temperature Cycling ◽

Cold Chain ◽

Refrigerated Storage ◽

Observational Assessment ◽

Ambient Temperatures ◽

C Storage ◽

The Stability

IntroductionOxytocin, administered via injection, is recommended by WHO for the prevention and treatment of postpartum haemorrhage. However, the susceptibility of oxytocin injection to thermal degradation has led WHO and UNICEF to recommend cold-chain storage of all oxytocin products. Nevertheless, some oxytocin products supplied to the global market are labelled for storage at ≤25°C, often with a shorter shelf-life relative to products labelled for refrigeration. Differences in labelled storage requirements can lead to uncertainties among stakeholders around the relative stability of oxytocin products and specifically whether ≤25°C products are more resistant to degradation. Such confusion can potentially influence policies associated with procurement, distribution, storage and the use of oxytocin in resource-poor settings.ObjectivesTo compare the stability of oxytocin injection ampoules formulated for storage at ≤25°C with those labelled for refrigerated storage.DesignAccelerated and temperature cycling stability studies were performed with oxytocin ampoules procured by the United Nations Population Fund (UNFPA) from four manufacturers.MethodUsing oxytocin ampoules procured by UNFPA, accelerated stability (up to 120 days) and temperature cycling (up to 135 days between elevated and refrigerated temperatures) studies were performed at 30°C, 40°C and 50°C. Oxytocin content was quantified using a validated HPLC-UV method.ResultsAll ampoules evaluated exhibited similar stability profiles under accelerated degradation conditions with the exception of one product formulated for ≤25°C storage, where the rate of degradation increased at 50°C relative to other formulations. Similar degradation trends at elevated temperatures were observed during temperature cycling, while no significant degradation was observed during refrigerated periods of the study.ConclusionOxytocin ampoules formulated for non-refrigerated storage demonstrated comparable stability to those labelled for refrigerated storage and should not be interpreted by stakeholders as offering a more stable alternative. Furthermore, these products should not be procured for use in territories with high ambient temperatures, where all oxytocin injection products should be supplied and stored under refrigerated conditions.

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Influence of Mechanical Surface Treatments on the Fatigue Performance of the Gamma TiAl Alloy Ti-45Al-9Nb-0.2C

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.1553 ◽

2007 ◽

Vol 539-543 ◽

pp. 1553-1558 ◽

Cited By ~ 1

Author(s):

Janny Lindemann ◽

Anja Kutzsche ◽

Michael Oehring ◽

Fritz Appel

Keyword(s):

Surface Roughness ◽

Shot Peening ◽

Tial Alloy ◽

Elevated Temperatures ◽

Lower Surface ◽

Fatigue Performance ◽

Ambient Temperatures ◽

Roller Burnishing ◽

Compressive Stresses ◽

Wide Range

The effect of shot peening and roller burnishing on the fatigue performance of the γ(TiAl) alloy Ti-45Al-9Nb-0.2C was investigated over a wide range of processing intensities. At optimized conditions shot peening and roller burnishing can markedly improve the fatigue strength at ambient temperatures. For temperatures above 650 °C, the residual compressive stresses induced by shot peening and roller burnishing quickly relax. This indicates that, at elevated temperatures, surface roughness and dislocation strengthening become more important for the fatigue performance of mechanically surface-treated components. Roller burnishing leads to much lower surface roughness than shot peening, resulting in more effective improvement of high temperature fatigue performance. However, surface strengthening by shot peening can also be beneficial for the fatigue performance at elevated temperatures, when the surface roughness is reduced by subsequent polishing.

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