JP BIRAT - Academia.edu (original) (raw)

Papers by JP BIRAT

Revue de Métallurgie, 1991

In the last ten years, Europe has been a very active player in the development of new continuous ... more In the last ten years, Europe has been a very active player in the development of new continuous casting techniques for thin slabs or strip.In the thin slab area, SMS, followed by MDH, Danieli and Voest-Alpine, has shown that high speed casting of thin slabs makes it possible to produce flat products economically at the mini-mill scale.British Steel with its Horizontal Caster and the Thyssen/Usinor Sacilor/SMS consortium with the CPR technology are exploring new fields.In the strip casting area, the programs are numerous and cover most of the possible technologies from single-roll to twin roll and belt & roll processes : in Germany (Krupp - VDM), in France (IRSID), in Italy (CSM - ILVA), or in Austria (Voest - Allegheny-Ludlum).Within the European Community, the ECSC Technical Research on Steel has had an important catalytic effect, especially in the field of strip casting.

Revue de Métallurgie, 1982

This document represents work in progress and is intended to generate comment and discussion. It ... more This document represents work in progress and is intended to generate comment and discussion. It is not a fully polished publication. The views expressed herein are those of the authors and do not necessarily reflect the views of the United Nations Industrial Development Organisation and its partners. This technical synthesis report captures the main findings drawn from five sectoral assessment reports that were commissioned by expert consultants to the CCS Industrial Sector Roadmap project, namely: high purity CO 2 sources, refineries, cement, iron and steel and biomass based; and from the reports from the workshops undertaken as part of the development of the Roadmap.

Journal of Magnetism and Magnetic Materials

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Le recyclage de l'acier est une activite industrielle fortement structuree, aussi ancienne qu... more Le recyclage de l'acier est une activite industrielle fortement structuree, aussi ancienne que la siderurgie elle-meme. L'acier recycle est d'ailleurs designe par un vieux mot francais, la ferraille, dont l'origine remonte a 1349 [1]

Revue de Métallurgie, 1989

Revue de Métallurgie, 1995

Looking at the changes expected at the various production stages of steel, different overall scen... more Looking at the changes expected at the various production stages of steel, different overall scenarios can be imagined for the structure of the future steel plant : increased use of scrap as the source of iron, new ways of steelmaking, production processes more environment friendly, shorter production routes, flexibility, variety and quickness in the response to customers needs, etc. These trends favor relatively small production units and change the operation conditions of large units

Revue de Métallurgie, 1992

For billets and blooms, centerline segregation and V-segregates resuit from the cracking of the m... more For billets and blooms, centerline segregation and V-segregates resuit from the cracking of the mushy zone under thermomechanical deformations inducing tension in the product core. Segregation level can be reduced by a control of the differential deformations between the solidified shell and the mushy zone at the vicinity of the liquid pool end. This goal can be reached by a precise control of the cooling of the product shell. Experiments on high ingots and industrial results on a billets continuous caster confirm the theoretical approach.This new process, called Unitherm, makes it possible to reduce certerline segregation in long products, better than a combined electromagnetic stirring (in mould and final EMS) for high carbon steel grades. This paper presents the results obtained at the semi-industrial and industrial scales.

Revue de Métallurgie, 1998

An increasing part of recycled steel is galvanized. Therefore, the steel industry plays an active... more An increasing part of recycled steel is galvanized. Therefore, the steel industry plays an active role in recycling zinc at the same time as steel. The text gives an overview of the available technologies, with a perspective on technical and economical questions that need to be addressed.

Revue de Métallurgie, 1997

Depuis longtemps, la modelisation joue un role important dans les metiers de la siderurgie. En re... more Depuis longtemps, la modelisation joue un role important dans les metiers de la siderurgie. En realite, ce mot recouvre des activites tres differentes, qui font appel a des approches variees et qui correspondent a differents objectifs. Un certain nombre d'exemples donnes dans cet article illustrent cette diversite. Depuis quelques annees, de nouveaux outils informatiques permettent d’explorer de nouvelles voies. La siderurgie y fait de plus en plus appel, sans pour autant negliger l’experimentation et la modelisation physique.

Revue de Métallurgie, 1979

Revue de Métallurgie, 1993

Face a l’influence de l’effet de serre sur le climat, la siderurgie, qui emet en France environ 2... more Face a l’influence de l’effet de serre sur le climat, la siderurgie, qui emet en France environ 26 Mt de CO 2 , dispose de differents remedes : les economies d’energie, le recyclage de l’acier, la fusion de ferraille, l’energie electrique et, a plus long terme, le recours a l’hydrogene comme reducteur.L’extension de la filiere electrique est une reponse adequate a cette question dans le court et le moyen terme.

Journal of Raman Spectroscopy, 2015

The accurate determination of the diffusion coefficient of dissolved CO2 in aqueous solutions is ... more The accurate determination of the diffusion coefficient of dissolved CO2 in aqueous solutions is a key parameter to predict the transport of the dissolved gas in the aqueous solution of porous aquifers and caprocks in the context of the mitigation of greenhouse gases emissions. A better understanding of the diffusion kinetics of dissolved CO2 as a function of subsurface conditions is essential to ensure the integrity of CO2 storage in saline aquifers. Experimental data are available to predict the CO2 diffusion kinetics as a function of temperature and pressure. However, the impact of salinity on CO2 diffusivity is still poorly documented. In this work, the diffusion coefficients of dissolved CO2 were determined using in situ Raman microspectrometry in Fused Silica Capillaries in a range of salinity from 0.0 to 6.0 molNaCl kg−1H2O. The diffusion coefficient of CO2 dissolved in pure water at 21 ± 1 °C and 40 bar is 1.71 × 10−9 ± 0.06 m2 s−1. In the same conditions of pressure and tem...

ESTEP's SRA vision is to manage a smooth cooperation between the anthroposphere and the bio/e... more ESTEP's SRA vision is to manage a smooth cooperation between the anthroposphere and the bio/ecosphere, with the mutual respect of the different players, and the challenges that the sector faces in terms of R&I in relation to SUSTAINABLE steel production. The focus is on reducing the environmental footprint of steel production and steel solutions by reducing resource consumption, fostering the use of secondary raw materials and thus accelerating the move towards a more closed-loop economy, by implementing energy efficiency, saving exergy, implementing process integration and ecodesign approaches. It also means reducing emissions and addressing complex issues such as climate change with ambitious targets or the preservation of biodiversity by internalizing the value of ecosystem services in business models.

Revue de Métallurgie, 2001

International Journal of Mineral Processing, 2004

The objective of this study is to contribute to the understanding of the fragmentation of end-of-... more The objective of this study is to contribute to the understanding of the fragmentation of end-of-life goods during shredding. Investigations have been carried out on laboratory-and industrial-scale shredders in order to establish the relationship between specific energy consumption, fragment size and degree of liberation of the metal/metal and nonmetal/metal composites by analyzing the influence of operating parameters on shredded scrap quality.

Electrochimica Acta, 2010

The electrochemical conversion in alkaline solutions of single hematite particles, weighting betw... more The electrochemical conversion in alkaline solutions of single hematite particles, weighting between 3 mg and 1 g, could be observed at macro-and microscopic scales, thanks to a dedicated experimental configuration. The results presented here reveal a very specific reaction mode at both scales, notably with a layer of metal progressing on the surface of the solid particle during the electrochemical reduction. In addition, conversion in the volume of the solid was observed. Mössbauer and chemical analysis of the iron metal content reveals a high Faradaic efficiency at the various stage of the conversion, and confirm magnetite phase as a key intermediate. Microscopic scale observations of hematite/magnetite conversion are presented, showing the solid-state feature of this reaction at low temperature. These observations together with the quantitative results lead to the proposal of a simple electrochemical model allowing the current variation during the electroreduction of hematite particles to iron metal to be predicted. The model provides the value for the current density related to the hematite reduction to iron, regardless of the shape or the size of the original particles.

Revue de Métallurgie, 1999

Energy Procedia, 2013

A core flow test autoclave has been designed in order to reproduce an injection well at a scale o... more A core flow test autoclave has been designed in order to reproduce an injection well at a scale of 1/20. This autoclave allows the CO 2 injection into a steel tube cemented to a core sample of red sandstone from the Triassic formations of Lorraine (France). Temperature and pressure gradients can be recorded between the injection point and the confining water phase. Such gradients imply solubility gradients of CO 2 and mineral species into the water phase as permeability changes with time. Some chemical reactions can be observed from collected sample at the end of the experiment. Precipitation and dissolution are suspected both into the cement and rock phases. No fracturing is observed. Cement-rock interface is not opened.