Materials are deeply connected with the environment, because they stem from raw materials extracted from the geosphere, rely on large amounts of energy and of water in their production stage, project emissions to air, water and soil when their ores (or minerals) are mined, when they are made in steel mills or cement kilns, including very significant amounts of greenhouse gases. They also contribute to emissions and energy consumption of the artifacts of which they are part, either consumption or investment goods. Their connection with the biosphere raises many issues, in terms of toxicology, ecotoxicology or biodiversity or simply of public health or in the working place. Materials, as an essential part of the anthroposphere, interact deeply with the anthroposphere itself but also with the biosphere, the geosphere, the atmosphere and the hydrosphere, thus with nature in a general way through mechanisms which can no longer simply be described at the margin, as resource depletion or as pollution. This raises issues related to the sustainability of materials in human activities, in which they are deeply immersed and entangled. The standard way of dealing with these environmental issues is to invoke sustainability and to explain that all actors are engaged in sustainable development, a morals or an ethics that points in which direction to go: all players in the materials field, industry, institutions and research, claim allegiance to sustainable development. At a more technical level, specific tools like Life Cycle Assessment (LCA) are used extensively to measure the interaction of materials with the environment. This, however, is not enough to deal properly with the environmental issues of materials, because these issues are not marginal any longer: the anthroposphere has become so large with respect to the biosphere, the geosphere and the planet in general that environmental risk is now part of modern life, especially in connection with climate change and the loss of biodiversity. To go deeper in analyzing the connection of human activities with nature, it is therefore necessary to reach out to SSH (Social Science and Humanities) disciplines and particularly to environmental ethics. This is a prerequisite for materials scientists (and others) to act decisively in the future in the face of the danger that lies ahead of us. The present paper reviews the advances of environmental ethics, a fairly young discipline born in the 1970s, in as far as it can help all actors on the world anthropospheric theater choose their lines for the future in a more conscious and sophisticated way than simply claiming obedience to sustainability. We will review briefly intellectual forerunners of the discipline like Jean-Jacques Rousseau, Henri David Thoreau, Rachel Carson or Paul Ehrlich. This will help flesh out well-known concepts like the precautionary principle or the “polluter-pays” principle, which are invoked in creating new materials or new processes to keep pol
{"title":"The environment and materials, from the standpoints of ethics, social sciences, law and politics","authors":"J. Birat","doi":"10.1051/MATTECH/2018067","DOIUrl":"https://doi.org/10.1051/MATTECH/2018067","url":null,"abstract":"Materials are deeply connected with the environment, because they stem from raw materials extracted from the geosphere, rely on large amounts of energy and of water in their production stage, project emissions to air, water and soil when their ores (or minerals) are mined, when they are made in steel mills or cement kilns, including very significant amounts of greenhouse gases. They also contribute to emissions and energy consumption of the artifacts of which they are part, either consumption or investment goods. Their connection with the biosphere raises many issues, in terms of toxicology, ecotoxicology or biodiversity or simply of public health or in the working place. Materials, as an essential part of the anthroposphere, interact deeply with the anthroposphere itself but also with the biosphere, the geosphere, the atmosphere and the hydrosphere, thus with nature in a general way through mechanisms which can no longer simply be described at the margin, as resource depletion or as pollution. This raises issues related to the sustainability of materials in human activities, in which they are deeply immersed and entangled. The standard way of dealing with these environmental issues is to invoke sustainability and to explain that all actors are engaged in sustainable development, a morals or an ethics that points in which direction to go: all players in the materials field, industry, institutions and research, claim allegiance to sustainable development. At a more technical level, specific tools like Life Cycle Assessment (LCA) are used extensively to measure the interaction of materials with the environment. This, however, is not enough to deal properly with the environmental issues of materials, because these issues are not marginal any longer: the anthroposphere has become so large with respect to the biosphere, the geosphere and the planet in general that environmental risk is now part of modern life, especially in connection with climate change and the loss of biodiversity. To go deeper in analyzing the connection of human activities with nature, it is therefore necessary to reach out to SSH (Social Science and Humanities) disciplines and particularly to environmental ethics. This is a prerequisite for materials scientists (and others) to act decisively in the future in the face of the danger that lies ahead of us. The present paper reviews the advances of environmental ethics, a fairly young discipline born in the 1970s, in as far as it can help all actors on the world anthropospheric theater choose their lines for the future in a more conscious and sophisticated way than simply claiming obedience to sustainability. We will review briefly intellectual forerunners of the discipline like Jean-Jacques Rousseau, Henri David Thoreau, Rachel Carson or Paul Ehrlich. This will help flesh out well-known concepts like the precautionary principle or the “polluter-pays” principle, which are invoked in creating new materials or new processes to keep pol","PeriodicalId":43816,"journal":{"name":"Materiaux & Techniques","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41987845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael Kohlgrüber, A. Schröder, Félix Bayón Yusta, Asier Arteaga Ayarza
A new innovation paradigm is needed to answer the societal, economic and environmental challenges the world and companies are facing. The EU funded Horizon 2020 SPIRE Project “Coordinating Optimisation of Complex Industrial Processes” (COCOP) is combining technological and social innovation within a steel company pilot case (Sidenor). The project aims at reducing raw materials consumption (and energy and emissions reduction as well) by plant-wide optimisation of production processes based on a software solution and at the same time changing social practices. Key for COCOP is a methodology integrating technological innovation within a social innovation process of co-creation and co-development by involving (potential) users of the future software system and relevant stakeholders right from the beginning; thereby improving effectiveness and impact of the innovations and the implementation process. This involvement is instructed and measured by social key performance indicators (social KPIs) and operationalised in surveys (questionnaire and interviews) with future users, engineers and external experts (from different industry sectors not involved in the project). The article presents the results of the starting point of COCOP illustrating the future user perspective of the pilot steel company (Sidenor) contrasted by the view of external experts – seriously taking into account the interfaces between technology, human and organisation.
{"title":"A new innovation paradigm: combining technological and social innovation","authors":"Michael Kohlgrüber, A. Schröder, Félix Bayón Yusta, Asier Arteaga Ayarza","doi":"10.1051/MATTECH/2018065","DOIUrl":"https://doi.org/10.1051/MATTECH/2018065","url":null,"abstract":"A new innovation paradigm is needed to answer the societal, economic and environmental challenges the world and companies are facing. The EU funded Horizon 2020 SPIRE Project “Coordinating Optimisation of Complex Industrial Processes” (COCOP) is combining technological and social innovation within a steel company pilot case (Sidenor). The project aims at reducing raw materials consumption (and energy and emissions reduction as well) by plant-wide optimisation of production processes based on a software solution and at the same time changing social practices. Key for COCOP is a methodology integrating technological innovation within a social innovation process of co-creation and co-development by involving (potential) users of the future software system and relevant stakeholders right from the beginning; thereby improving effectiveness and impact of the innovations and the implementation process. This involvement is instructed and measured by social key performance indicators (social KPIs) and operationalised in surveys (questionnaire and interviews) with future users, engineers and external experts (from different industry sectors not involved in the project). The article presents the results of the starting point of COCOP illustrating the future user perspective of the pilot steel company (Sidenor) contrasted by the view of external experts – seriously taking into account the interfaces between technology, human and organisation.","PeriodicalId":43816,"journal":{"name":"Materiaux & Techniques","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48231055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Colla, I. Matino, S. Dettori, A. Petrucciani, A. Zaccara, Valentine Weber, Sahar Salame, N. Zapata, S. Bastida, A. Wolff, R. Speets, L. Romaniello
The European Steel industry is spending considerable efforts in order to improve the socio-economic and environmental sustainability of its processes by promoting any development, which can increase efficiency and lower the environmental impact of the steel production processes. In particular, the European iron and steel sector is strongly committed toward the reduction of energy consumptions and CO2 emissions. Process gases are a very valuable resource: possibilities exist to consider these gases as an intermediate by-product for the production of other valuable energy carriers or products with an associated environmental benefit. Therefore, the process gas networks, especially inside the integrated steelworks, have a fundamental function, as they allow meeting the demand of many processes and producing energy through dedicated facilities. They can also support the production processes by internal electric energy generation and often by supplying energy outside the plant boundaries. On the other hand, such networks are very complex systems interacting with many different production steps and the management of such complex systems is a very difficult task, where many often-counteracting factors need to be jointly taken into account. This paper presents the first outcomes of the research project entitled “Optimization of the management of the process gas network within the integrated steelworks (GASNET)”, which aims at developing a Decision Support System helping the energy managers and other concerned technical personnel to implement an optimized off-gases management and exploitation considering environmental and economic objectives. A series of Key Performance Indicators has been elaborated, in order to monitor the efficiency of the gas management and the objectives of the optimization have been defined. The overall structure of the project and the ongoing work will also be outlined in the paper.
{"title":"Assessing the efficiency of the off-gas network management in integrated steelworks","authors":"V. Colla, I. Matino, S. Dettori, A. Petrucciani, A. Zaccara, Valentine Weber, Sahar Salame, N. Zapata, S. Bastida, A. Wolff, R. Speets, L. Romaniello","doi":"10.1051/MATTECH/2018068","DOIUrl":"https://doi.org/10.1051/MATTECH/2018068","url":null,"abstract":"The European Steel industry is spending considerable efforts in order to improve the socio-economic and environmental sustainability of its processes by promoting any development, which can increase efficiency and lower the environmental impact of the steel production processes. In particular, the European iron and steel sector is strongly committed toward the reduction of energy consumptions and CO2 emissions. Process gases are a very valuable resource: possibilities exist to consider these gases as an intermediate by-product for the production of other valuable energy carriers or products with an associated environmental benefit. Therefore, the process gas networks, especially inside the integrated steelworks, have a fundamental function, as they allow meeting the demand of many processes and producing energy through dedicated facilities. They can also support the production processes by internal electric energy generation and often by supplying energy outside the plant boundaries. On the other hand, such networks are very complex systems interacting with many different production steps and the management of such complex systems is a very difficult task, where many often-counteracting factors need to be jointly taken into account. This paper presents the first outcomes of the research project entitled “Optimization of the management of the process gas network within the integrated steelworks (GASNET)”, which aims at developing a Decision Support System helping the energy managers and other concerned technical personnel to implement an optimized off-gases management and exploitation considering environmental and economic objectives. A series of Key Performance Indicators has been elaborated, in order to monitor the efficiency of the gas management and the objectives of the optimization have been defined. The overall structure of the project and the ongoing work will also be outlined in the paper.","PeriodicalId":43816,"journal":{"name":"Materiaux & Techniques","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48222036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Čech, P. Haušild, M. Karlík, V. Kadlecová, J. Čapek, F. Průša, P. Novák
FeAl20Si20 (wt.%) powders prepared by mechanical alloying from different initial feedstock materials (Fe, Al, Si, FeAl27) were investigated in this study. Scanning electron microscopy, X-ray diffraction and nanoindentation techniques were used to analyze microstructure, phase composition and mechanical properties (hardness and Young’s modulus). Finite element model was developed to account for the decrease in measured values of mechanical properties of powder particles with increasing penetration depth caused by surrounding soft resin used for embedding powder particles. Progressive homogenization of the powders’ microstructure and an increase of hardness and Young’s modulus with milling time were observed and the time for complete homogenization was estimated.
{"title":"Mechanical properties of FeAlSi powders prepared by mechanical alloying from different initial feedstock materials","authors":"J. Čech, P. Haušild, M. Karlík, V. Kadlecová, J. Čapek, F. Průša, P. Novák","doi":"10.1051/MATTECH/2018063","DOIUrl":"https://doi.org/10.1051/MATTECH/2018063","url":null,"abstract":"FeAl20Si20 (wt.%) powders prepared by mechanical alloying from different initial feedstock materials (Fe, Al, Si, FeAl27) were investigated in this study. Scanning electron microscopy, X-ray diffraction and nanoindentation techniques were used to analyze microstructure, phase composition and mechanical properties (hardness and Young’s modulus). Finite element model was developed to account for the decrease in measured values of mechanical properties of powder particles with increasing penetration depth caused by surrounding soft resin used for embedding powder particles. Progressive homogenization of the powders’ microstructure and an increase of hardness and Young’s modulus with milling time were observed and the time for complete homogenization was estimated.","PeriodicalId":43816,"journal":{"name":"Materiaux & Techniques","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44601976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This author applied personal practice in order to develop and subsequently demonstrate the feasibility of applying the techniques of inside painting of traditional Chinese snuff bottles, so as to create a body of works demonstrating totally different effects and styles. The techniques focus on free-hand blowing in this section. This new form of inside painting shown could be applied to contemporary glass sculpture making and therefore reduce, or even solve, the monopoly of traditional style.
{"title":"Contemporary inside painting glass sculptures","authors":"Jianyong Guo","doi":"10.1051/MATTECH/2018062","DOIUrl":"https://doi.org/10.1051/MATTECH/2018062","url":null,"abstract":"This author applied personal practice in order to develop and subsequently demonstrate the feasibility of applying the techniques of inside painting of traditional Chinese snuff bottles, so as to create a body of works demonstrating totally different effects and styles. The techniques focus on free-hand blowing in this section. This new form of inside painting shown could be applied to contemporary glass sculpture making and therefore reduce, or even solve, the monopoly of traditional style.","PeriodicalId":43816,"journal":{"name":"Materiaux & Techniques","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41872516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The steel sector stands for a quarter of Ukraine’s industrial gross value added and is a backbone of the country’s economy. However, owing to lastingly insufficient investments to modernisation, the industry is largely obsolete: 70–80% of the production facilities are in operation beyond their final designed term of exploitation. Technology backwardness, coupled with excessive iron ore mining, results in an enormous environmental footprint. Owing to the domestic political and socioeconomic factors and severe competition on the global scale, the steel output hit its historic low in 2017. Recently, the EU became major Ukraine’s trade partner with steel export share of 32% in 2017. Modalities of this partnership will be gradually shaped in context of the EU-Ukraine Association Agreement (entered into force since 01.09.2017), which stipulates transposition into Ukrainian law of some European directives, potentially sensitive for the iron and steel sector. In this paper, the current state of Ukraine’s steel industry was analysed, focusing competitiveness and environmental impact. The analysis performed reveals that short-term implications of the Association Agreement may expose the Ukrainian steelmakers to additional costs; however, the need to comply with the EU regulations is seen as an important factor, motivating the steel industry to modernise and, in the long-term, improve its economic performance and reinforce competitiveness.
{"title":"Ukraine’s commitments under Association Agreement: challenges and opportunities for the steel industry","authors":"V. Shatokha","doi":"10.1051/MATTECH/2018044","DOIUrl":"https://doi.org/10.1051/MATTECH/2018044","url":null,"abstract":"The steel sector stands for a quarter of Ukraine’s industrial gross value added and is a backbone of the country’s economy. However, owing to lastingly insufficient investments to modernisation, the industry is largely obsolete: 70–80% of the production facilities are in operation beyond their final designed term of exploitation. Technology backwardness, coupled with excessive iron ore mining, results in an enormous environmental footprint. Owing to the domestic political and socioeconomic factors and severe competition on the global scale, the steel output hit its historic low in 2017. Recently, the EU became major Ukraine’s trade partner with steel export share of 32% in 2017. Modalities of this partnership will be gradually shaped in context of the EU-Ukraine Association Agreement (entered into force since 01.09.2017), which stipulates transposition into Ukrainian law of some European directives, potentially sensitive for the iron and steel sector. In this paper, the current state of Ukraine’s steel industry was analysed, focusing competitiveness and environmental impact. The analysis performed reveals that short-term implications of the Association Agreement may expose the Ukrainian steelmakers to additional costs; however, the need to comply with the EU regulations is seen as an important factor, motivating the steel industry to modernise and, in the long-term, improve its economic performance and reinforce competitiveness.","PeriodicalId":43816,"journal":{"name":"Materiaux & Techniques","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45473054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L’accumulation des sédiments en couche successives au fond des cours d’eau conduit à leur envasement. L’objectif de cette étude est de démontrer l’utilisation pratique des sédiments du port de Bethioua dans la fabrication des briques. Les sédiments ont été introduits dans le mélange de référence avec un taux de substitution de 20 % en tant que remplacement de l’argile utilisée pour la fabrication des briques. Des éprouvettes de briques de référence et de briques à base de sédiments marins de formes cylindriques ont été préparées en suivant le même processus de fabrication. Les éprouvettes de briques ont été cuites à des températures comprises entre 600 et 900 °C avec une durée de cuisson de 6 et 24 h. Elles ont ensuite été soumises à des essais de résistance à la compression. Les résultats obtenus ont montré que les briques à base de sédiments avec une substitution de 5 et 10 % présentent une meilleure résistance que les briques de référence. La substitution par des sédiments avec cette concentration augmente la résistance à la compression avec une faible température et une faible durée de cuisson. Les résultats de cette étude démontrent que la production de briques cuites avec les sédiments marins du port de Bethioua améliore nettement et donnent une meilleure résistance que la résistance de la brique de référence pour un ajout de 5 et 10 %. Le taux de 15 % donne une résistance comparable à celui de la résistance de la barbotine de brique.
{"title":"Étude des caractéristiques thermiques et mécaniques des briques à base de sédiments de dragage portuaire","authors":"Benyerou Djamila, Boudjenane Nasr-Eddine, Belhadri Mansour","doi":"10.1051/mattech/2019032","DOIUrl":"https://doi.org/10.1051/mattech/2019032","url":null,"abstract":"L’accumulation des sédiments en couche successives au fond des cours d’eau conduit à leur envasement. L’objectif de cette étude est de démontrer l’utilisation pratique des sédiments du port de Bethioua dans la fabrication des briques. Les sédiments ont été introduits dans le mélange de référence avec un taux de substitution de 20 % en tant que remplacement de l’argile utilisée pour la fabrication des briques. Des éprouvettes de briques de référence et de briques à base de sédiments marins de formes cylindriques ont été préparées en suivant le même processus de fabrication. Les éprouvettes de briques ont été cuites à des températures comprises entre 600 et 900 °C avec une durée de cuisson de 6 et 24 h. Elles ont ensuite été soumises à des essais de résistance à la compression. Les résultats obtenus ont montré que les briques à base de sédiments avec une substitution de 5 et 10 % présentent une meilleure résistance que les briques de référence. La substitution par des sédiments avec cette concentration augmente la résistance à la compression avec une faible température et une faible durée de cuisson. Les résultats de cette étude démontrent que la production de briques cuites avec les sédiments marins du port de Bethioua améliore nettement et donnent une meilleure résistance que la résistance de la brique de référence pour un ajout de 5 et 10 %. Le taux de 15 % donne une résistance comparable à celui de la résistance de la barbotine de brique.","PeriodicalId":43816,"journal":{"name":"Materiaux & Techniques","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42474047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
When the unprecedented environmental cracking of steel in liquid ammonia was collectively studied, its undisputable “anodic character” was taken as the signature of a stress corrosion cracking mechanism, which is effectively the case in aqueous corrosion. Conversely, when the metallurgical precautions proved to be the same as in sour service, this strongly suggested a hydrogen stress cracking mechanism. In aqueous corrosion, however, this can only occur by cathodic hydrogen charging at low potential, and for 50 years, this basic contradiction could never be overcome. Actually, it occurs that the liquid ammonia solvent (NH3) is 50% richer in hydrogen than the water solvent (OH2), so that hydrogen gas can also be produced by a partial oxidisation into ½ N2 + H2. This therefore induces a theoretical possibility of an “anodic” hydrogen charging, or more exactly a protonic cathodic reaction only running at high potential on passive iron in oxygen contaminated ammonia. And once the detrimental potential is achieved through appropriate combinations of oxygen and water traces, the charging process becomes an autonomous oxidation-reduction at the steel surface NH3 → ½ N2 + H2 + (H+ + e−)steel. In Part II (Jean-Louis Crolet, Matériaux & Techniques 107, 402, 2019), this new assumption will be successfully confronted to all the factual data from both field and laboratory experience.
{"title":"Detailed mechanisms of hydrogen charging and hydrogen stress cracking of steel in liquid ammonia storage","authors":"J. Crolet","doi":"10.1051/mattech/2019022","DOIUrl":"https://doi.org/10.1051/mattech/2019022","url":null,"abstract":"When the unprecedented environmental cracking of steel in liquid ammonia was collectively studied, its undisputable “anodic character” was taken as the signature of a stress corrosion cracking mechanism, which is effectively the case in aqueous corrosion. Conversely, when the metallurgical precautions proved to be the same as in sour service, this strongly suggested a hydrogen stress cracking mechanism. In aqueous corrosion, however, this can only occur by cathodic hydrogen charging at low potential, and for 50 years, this basic contradiction could never be overcome. Actually, it occurs that the liquid ammonia solvent (NH3) is 50% richer in hydrogen than the water solvent (OH2), so that hydrogen gas can also be produced by a partial oxidisation into ½ N2 + H2. This therefore induces a theoretical possibility of an “anodic” hydrogen charging, or more exactly a protonic cathodic reaction only running at high potential on passive iron in oxygen contaminated ammonia. And once the detrimental potential is achieved through appropriate combinations of oxygen and water traces, the charging process becomes an autonomous oxidation-reduction at the steel surface NH3 → ½ N2 + H2 + (H+ + e−)steel. In Part II (Jean-Louis Crolet, Matériaux & Techniques 107, 402, 2019), this new assumption will be successfully confronted to all the factual data from both field and laboratory experience.","PeriodicalId":43816,"journal":{"name":"Materiaux & Techniques","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47312773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samia Arezki Née Djadouf, Nasser Chelouah, A. Tahakourt
Ce travail évalue l’effet de la granulométrie du broyat de noyaux d’olive (BNO) sur les propriétés de la brique de terre cuite. Les noyaux d’olive concassés sont tamisés pour séparer les différents diamètres (1,5, 1, 0,5 et 0,25 mm). Nous avons confectionné quatre séries d’échantillons contenant 5, 10, 15 et 20 % de BNO dans la masse d’argile pour les essais. Les matières premières argile et BNO ont été caractérisées aux moyens d’analyses chimique et minéralogique, analyse thermique gravimétrique TG-DTG. Les propriétés physico-mécanique et thermique des éprouvettes cuites à 1000 °C, telles que, la porosité, l’absorption d’eau, la résistance à la compression, et la conductivité thermique ont été évaluées. Cette étude présente des résultats intéressants pour augmenter le pouvoir d’isolation des briques. Nous avons œuvré sur l’optimisation du diamètre de l’ajout, en travaillant sur la réduction des ponts thermiques et la diminution des transferts de chaleur dans les cavités produites par la consumation du BNO. Nous avons constaté que pour des diamètres plus petits de l’ajout; la conductivité thermique est de moindre avec des résistances à la compression avérées.
{"title":"Influence de la distribution en taille (broyat de noyaux d’olive) sur les propriétés de la brique","authors":"Samia Arezki Née Djadouf, Nasser Chelouah, A. Tahakourt","doi":"10.1051/mattech/2019024","DOIUrl":"https://doi.org/10.1051/mattech/2019024","url":null,"abstract":"Ce travail évalue l’effet de la granulométrie du broyat de noyaux d’olive (BNO) sur les propriétés de la brique de terre cuite. Les noyaux d’olive concassés sont tamisés pour séparer les différents diamètres (1,5, 1, 0,5 et 0,25 mm). Nous avons confectionné quatre séries d’échantillons contenant 5, 10, 15 et 20 % de BNO dans la masse d’argile pour les essais. Les matières premières argile et BNO ont été caractérisées aux moyens d’analyses chimique et minéralogique, analyse thermique gravimétrique TG-DTG. Les propriétés physico-mécanique et thermique des éprouvettes cuites à 1000 °C, telles que, la porosité, l’absorption d’eau, la résistance à la compression, et la conductivité thermique ont été évaluées. Cette étude présente des résultats intéressants pour augmenter le pouvoir d’isolation des briques. Nous avons œuvré sur l’optimisation du diamètre de l’ajout, en travaillant sur la réduction des ponts thermiques et la diminution des transferts de chaleur dans les cavités produites par la consumation du BNO. Nous avons constaté que pour des diamètres plus petits de l’ajout; la conductivité thermique est de moindre avec des résistances à la compression avérées.","PeriodicalId":43816,"journal":{"name":"Materiaux & Techniques","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42455634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}