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This work outlines an integrated methodology for converting metallurgical by-products into high added value products, through an essentially zero-waste process. Thermodynamic modelling and conceptual design for processing bauxite residues (red mud) from the primary aluminium industry and ferro-nickel production slags are presented as examples. Furthermore, results of semiindustrial scale experiments for processing bauxite residues are illustrated, along with a preliminary financial analysis and an exergy flowsheet of the new conceptual alumina refinery, all confirming the financial viability as well as the resource-efficient utilization of the proposed technology.

9 páginas, ilustraciones y tablas estadísticas., A series of incubation and leaching experiments were performed to assess the feasibility of three industrial by-products (red gypsum (RG), sugar foam (SF) and ashes from the combustion of biomass (ACB)) to reduce the leachability of Cu, Pb, Zn and As in a sediment of São Domingos mine (Portugal). The changes in the element solid phase speciation were also evaluated by applying a sequential extraction procedure. All amendments significantly reduced the leachability of Zn and Cu, whereas the treatment with RG + SF + ACB also decreased the mobility of As. The reduction in Cu leachability was especially remarkable. This could be due to the great affinity of carbonates (included in SF and SF + ACB amendments) to precipitate with Cu, and maghemite and rutile (RG amendment) for acting as relevant sorbents for Cu. Pb was the least mobile element in the sediment and none of the treatments reduced its mobility. The sequential extraction reveals that the amendments induced a significant decrease in the concentration of elements associated with the residual fraction. Cu, Pb and As are redistributed from the residual fraction to the Al, Fe, and Mn hydr(oxides) fraction and Zn from the residual fraction to the water/acid soluble, exchangeable and bound to carbonates pool., AGL2005-07017-C03-03. MPRJ

Στην παρούσα διατριβή ερευνήθηκε η αξιοποίηση μεταλλευτικών, βιομηχανικών παραπροϊόντων, των στερεών Υπολειμμάτων Βορίου (ΥΒ), που δημιουργούνται σε διάφορα στάδια κατά την παραγωγική διαδικασία προϊόντων βορίου. Τα εν λόγω παραπροϊόντα, που κατηγοριοποιούνται σε πέντε ποιότητες, SBW, DBW, SSBW, TBW και MBW, χρησιμοποιήθηκαν ως πρόσθετο Α’ υλών για την παραγωγή τούβλων και κεραμιδιών, και ως Α΄ ύλη για την παρασκευή τεχνητών ελαφροαδρανών. Πραγματοποιήθηκε φυσικοχημικός χαρακτηρισμός και θερμική ανάλυση όλων των ΥΒ. Στη συνέχεια μελετήθηκε η επίδραση προσθήκης διαφορετικών συγκεντρώσεων ΥΒ (SBW και SSBW) σε αργιλούχες Α΄ ύλες. Έγινε μια πρώτη προσέγγιση παρασκευής και ελέγχου κεραμικών δοκιμίων με τη μέθοδο της ξηρής ανάμιξης και αξονικής συμπίεσης, προκειμένου να περιοριστεί το φαινόμενο διάχυσης υδατοδιαλυτών ενώσεων βορίου που περιέχονται στα ΥΒ. Η προσθήκη 5%κβ SSBW και θερμοκρασία όπτησης 900-950°C οδήγησε σε κεραμικά με παραπλήσιες ή ακόμα και βελτιωμένες ιδιότητες (αυξημένες μηχανικές αντοχές) συγκριτικά με τα κεραμικά αναφοράς. Επιπλέον εξετάστηκε η παραγωγή δειγμάτων με ΥΒ (SBW) και διάλυμα εμπορίου με βορικό (Evansite®) ακολουθώντας διαδικασία παραπλήσια της βιομηχανικής πρακτικής. Στους 1000°C, παρατηρήθηκε μείωση της απορρόφησης νερού και αύξηση της αντοχής σε κάμψη για τα δείγματα με βορικά, σε σύγκριση με τα δείγματα αναφοράς. Η προσθήκη βορικών ευνόησε τη δημιουργία νέων κρυσταλλικών κατά την όπτηση. Δεδομένης της χημικής και ορυκτολογικής σύνθεσης των ΥΒ (πλούσια σε συλλιπάσματα και υψηλές απώλειες πύρωσης), πραγματοποιήθηκε επιπρόσθετα μελέτη των φυσικοχημικών μηχανισμών θερμικής διάσπασής τους. Σε θερμαινόμενη τράπεζα παρατηρήθηκε η ικανότητα διόγκωσης και ανάπτυξης ρευστής φάσης των ΥΒ, καθώς και μιγμάτων αυτών με άλλα υλικά, με σκοπό την εργαστηριακή παραγωγή ελαφροαδρανών. Βάσει των αποτελεσμάτων προτάθηκε ένα μίγμα αποτελούμενο από 70%κβ ΥΒ, 20%κβ αργιλούχο μίγμα και 10%κβ χαλαζιακή άμμο, για τη μορφοποίηση ξηρών σφαιριδίων. Απότομη θέρμανσή τους στους 760°C οδήγησε σε πορώδη υαλοποιημένα αδρανή με φαινόμενη πυκνότητα

The alkali–silica reaction (ASR) in concrete occurs by reaction of certain silica phases in the aggregates with alkalis and hydroxide ions in the pore solution of the hydrating cement to produce a hydrous alkali-silicate gel. This gel can swell by incorporating large amounts of water, causing severe and irreversible expansion and cracking of the concrete. The level of expansion and disruption in concrete containing reactive aggregate depends on the alkali content of the concrete and the reactivity of the aggregate. The levels of alkali that trigger the expansion depend, however, on the reactivity of the aggregates. Alkalis from Portland cement (OPC) are one of the major sources of these ions in concrete. The use of industrial by-products such as fly ash and slag has been found to be an effective preventive measure against ASR in concrete. This article presents the performance of biomass fly ash - an industrial by-product - in the mitigation/inhibition of ASR in concrete. Laboratory expansion tests were conducted to evaluate the performance of biomass fly ash, in replacement of OPC by 20% and 30% (w/w) in the experiments (ASTM C1260/ASTM C1567). The results revealed that biomass fly ash has a good potential in the expansion inhibition due to ASR. The authors wish to acknowledge Fundação para a Ciência e Tecnologia (FCT) for the financial support under project EXREACT PTDC/CTM/65243/2006) and PhD grant SFRH/BD/32500/2006. 1 4 7p DM/NMM 2011 3 a 8 de Julho

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:07:34Z No. of bitstreams: 1 S1516-35982010000200004.pdf: 114477 bytes, checksum: 249e3883ee30284df87cfbf9af3f788a (MD5) Made available in DSpace on 2013-08-22T19:07:34Z (GMT). No. of bitstreams: 1 S1516-35982010000200004.pdf: 114477 bytes, checksum: 249e3883ee30284df87cfbf9af3f788a (MD5) Previous issue date: 2010-02-01 Made available in DSpace on 2013-09-30T20:12:06Z (GMT). No. of bitstreams: 2 S1516-35982010000200004.pdf: 114477 bytes, checksum: 249e3883ee30284df87cfbf9af3f788a (MD5) S1516-35982010000200004.pdf.txt: 35700 bytes, checksum: 982160dd861be4ddf4ba2b7908a268fc (MD5) Previous issue date: 2010-02-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:18:17Z No. of bitstreams: 2 S1516-35982010000200004.pdf: 114477 bytes, checksum: 249e3883ee30284df87cfbf9af3f788a (MD5) S1516-35982010000200004.pdf.txt: 35700 bytes, checksum: 982160dd861be4ddf4ba2b7908a268fc (MD5) Made available in DSpace on 2014-05-20T15:18:17Z (GMT). No. of bitstreams: 2 S1516-35982010000200004.pdf: 114477 bytes, checksum: 249e3883ee30284df87cfbf9af3f788a (MD5) S1516-35982010000200004.pdf.txt: 35700 bytes, checksum: 982160dd861be4ddf4ba2b7908a268fc (MD5) Previous issue date: 2010-02-01 Item merged in doublecheck by Felipe Arakaki (fe.arakaki@gmail.com) on 2015-11-17T18:56:18Z Item was identical to item(s): 30320, 39761 at handle(s): http://hdl.handle.net/11449/30821, http://hdl.handle.net/11449/40263 Este trabalho foi conduzido para avaliar o valor nutritivo de silagens de capim-elefante (Pennisetum purpureum, Schum.) com 0, 4, 8, 12 e 16% de pedúnculo de caju (Anacardium occidentale L.) desidratado, com base na matéria natural. Utilizou-se o delineamento inteiramente casualizado com quatro repetições. Como silos experimentais, foram utilizados tambores plásticos de 210 L. Determinaram-se a composição nutricional, os valores de pH e os teores de nitrogênio amoniacal, ácido lático, acético, propiônico e butírico. A inclusão de pedúnculo de caju desidratado na ensilagem de capim-elefante promoveu aumento das concentrações de matéria seca (MS), proteína bruta (PB), extrato etéreo (EE), carboidratos não-fibrosos (CNF), nitrogênio insolúvel em detergente neutro (NIDN, % do N total), nitrogênio insolúvel em detergente ácido (NIDA, % do N total), pH e ácidos lático e propiônico. Por outro lado, os teores de FDN, FDA, hemicelulose, N-NH3 (% do N total) e ácido butírico diminuíram de forma linear conforme aumentaram os níveis do subproduto na ensilagem. O pedúnculo de caju desidratado não influenciou os teores de carboidratos totais e ácido acético das silagens. Esse subproduto pode ser ensilado com o capim-elefante até o nível de 16%, uma vez que aumenta os teores de PB e CNF e reduz os teores de FDN e FDA, melhorando o padrão de fermentação das silagens. The objective of this study was to evaluate the nutritive value of elephant grass (Pennisetum purpureum, Schum.) silages with the addition of 0, 4, 8, 12 and 16% dried cashew stalk (Anacardium occidentale L.) - DCS, based on the fresh matter. A randomized complete design with four replications was used. Twenty 210 L plastic drums were used as experimental silos. The levels were determined of the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, ether extract (EE), total carbohydrates (TC), non-fibrous carbohydrates (NFC), neutral detergent insoluble nitrogen (NDIN,% total N), acid detergent insoluble nitrogen (ADIN, % total N), pH values, ammonia nitrogen (in percentage of the total nitrogen, N-NH3, % total N), lactic acid, acetic acid, butyric acid and propionic acid. Adding DCS resulted in higher values of DM, CP, EE, NFC, NDIN (% total N), ADIN (% total N), pH, lactic acid and propionic acid. on the other hand, with increasing DCS levels, a linear decline was observed in values of NDF, ADF, hemicellulose, ammonia nitrogen (% total N) and butyric acid. DCS did not show effect on the TC and acetic acid in the silages. As a result, up to 16% dehydrated cashew stalk may be added to elephant-grass silages, based on the fresh matter, to increase CP and NFC levels and decrease NDF and ADF and improve the fermentation patterns. It should be taken into account that higher NDIN and ADIN values may interfere in nitrogen availability and therefore in further DM intake. Universidade Federal do Tocantins (UFT) UNESP Jaboticabal, São Paulo, Brazil Universidade Federal do Ceará (UFC) Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) UNESP Jaboticabal, São Paulo, Brazil

8 pages, figures, and tables statistics., This study evaluates the potential use of four industrial by-products (phosphogypsum (PG), red gypsum (RG), sugar foam (SF), and ashes from biomass combustion (ACB)), applied at two rates in single and combined amendments to reduce the mobility and availability of Pb, Zn and Ni in a metal-spiked acid soil. Leaching experiments were done to estimate leachability indexes and assess their effectiveness. Most of the treatments significantly reduced the metal leachability although only a few were effective for all metals. Based on principal component and cluster analysis, sugar foam (SF) and a mixture of RG and ACB (RG+ACB), both applied at high rate, were selected as first choices to reduce mobility and availability of the three metals. Metal sorption mechanisms involved in the reduction of their leachability were identified using scanning electron microscopy. In the SF-treated samples, the metals were found associated to amorphous Al-hydroxy polymers deposited on phyllosilicates and organic matter particles. In the (RG+ACB)-treated samples, Pb, Zn, and traces of Ni were found associated to Fe/Ti oxide phases with a significant concentration of S, suggesting the formation of metal-sulfate ternary complexes., This work was supported by the Spanish Ministry of Science and Innovation, research project AGL2005-07017-C03-03. MPRJ acknowledges a fellowship from CSIC (Spain). We are especially grateful to Laura Barrios for her assistance in the statistical treatment of the data. Fertiberia S.A., Azucarera Ebro S.A., Tioxide Europe S.A. and ENCE S.A. are gratefully acknowledged for supplying the waste samples studied.

8 pages, photos, figures, and tables statistics., Four industrial by-products (phosphogypsum, PG; red gypsum, RG; sugar foam, SF and ashes from the combustion of biomass, ACB) were evaluated as possible amendments for reducing the leachability and bioavailability of As and Se in a metalloid-spiked acidic soil. The treatments were applied as single, double and triple amendments and at two different rates. The effectiveness of the treatments was evaluated after a series of leaching experiments using a chelating agent (DTPA solution) or a weak acidification (acetic acid at pH 4.93). The most effective treatments (ACB and RG, both applied at high rate) were identified by means of Cluster Analysis using the leachability indexes. Different sorption mechanisms involved in the overall reduction of metalloid leachability were identified using scanning electron microscopy (SEM-BSE and SEM-EDS). In the ACB-treated samples, Se was found associated to organic matter aggregates and to Fe compounds. In the RG-treated samples, EDS analyses showed that As and Se were associated to Fe/Ti (hydr)oxides phases which are present not only in the by-product as maghemite and rutile, but also in the soil as hematite and goethite. In addition, the application of RG induced the formation of non-crystalline Al-hydroxy polymers with As and Se in their composition., Elsevier

This study reports the isolation of microorganisms that are resistant to environment containing limonene, the most important residue in the citrus industry. For the isolation, samples collected from strategic places of a citrus processing plant (yellow water, entrance and exit of the bagasse tank, effluent and deteriorated fruits found in bins, machine straps, fruit washers and plant floor), some citrus fruit and mint from local market were used. The samples were incubated in rotary shaker at 30ºC/150rpm for 48h or 7 days in YM medium containing 0.1% limonene. Great part of the 112 strains recovered after 48h and the 126 strains recovered after 7 days were identified as Gram positive bacilli, followed by Gram negative bacilli, yeasts and Gram positive cocci, besides five fungi. About half of the Gram positive and Gram negative bacilli and yeasts and some Gram positive Cocci were resistant to limonene concentrations up to 2% in the medium broth. Amongst them seventy were able to grow in mineral medium containing limonene as sole carbon source. The research described in this paper is the initial step for the exploration of flavor compounds production via biotransformation of limonene, a non-expensive by-product of citrus industry. Este estudo relata o isolamento de microrganismos resistentes a ambientes contendo limoneno, o mais importante resíduo da indústria citrícola. Para o isolamento, foram utilizadas amostras colhidas de pontos estratégicos de uma indústria processadora de laranja (água amarela, entrada e saída do tanque de bagaço, efluente e frutas deterioradas encontradas nos bins, nas correias dos equipamentos, nos lavadores e espalhadas pelo chão), além de frutas cítricas e hortelã adquiridas em mercado local. Cada amostra permaneceu incubada a 30ºC/150 rpm por 48h ou 7 dias em meio YM contendo 0,1% de limoneno. Dentre as 112 linhagens obtidas com 48h e as 126 com 7 dias, a grande maioria dos microorganismos isolados foram bacilos Gram positivos, seguidos por uma menor quantidade de bacilos Gram negativos, leveduras e cocos Gram positivos, além de cinco fungos. Cerca de metade das linhagens de bacilos Gram positivos e Gram negativos e de, leveduras e alguns de cocos Gram positivos resistiram à presença de até 2% de limoneno, dentre as quais 70 foram capazes de sobreviver em ambientes contendo limoneno como única fonte de carbono. O trabalho descrito nesse artigo representa o primeiro passo no desenvolvimento de processos de produção de compostos de aroma pela biotransformação do limoneno.

O experimento foi conduzido no Departamento de Zootecnia (UFLA) e no Laboratório de Alimentos (UNIFENAS), com o objetivo de avaliar o valor nutritivo do resíduo de lixadeira do algodão pela composição bromatológica (PB, FDN, FDA) e pela degradabilidade da MS e da FDN. Os tratamentos foram: T1 - in natura (IN); T2 - pressão e vapor (127ºC/1,5 kgf/cm²/35min; PV); T3 - 4% hidróxido de sódio (por 24 horas; NaOH); T4 - 3% uréia (por 28 dias; U); T5 - 4% NaOH + 3% uréia (NaOH/U); T6 - PV + 4% NaOH (PV/NaOH); T7 - PV + 3% uréia (PV/U). Pelos resultados referentes à composição química, conclui-se que os tratamentos associados foram mais eficientes em aumentar o valor nutritivo do resíduo, sendo o tratamento NaOH/U o que apresentou os melhores resultados para PB, FDN e FDA. Os maiores valores para a degradabilidade efetiva da MS foram verificados para o resíduo tratado com PV, U, NaOH/U, PV/NaOH, PV/U, que também apresentaram maior fração solúvel e menor fração insolúvel potencialmente degradável (b). Os tratamentos U, PV/NaOH e PV/U apresentaram as maiores de degradabilidade efetiva da FDN e maior fração solúvel. Os tratamentos associados aumentaram a degradabilidade e o valor nutritivo do resíduo de lixadeira do algodão. The experiment was carried out at the Department of Animal Science of the Universidade Federal de Lavras and at the Food Laboratory at the Universidade José do Rosário Vellano (UNIFENAS), with the objective to evaluate the nutritive value of cotton textile mill waste using chemical composition (DM, CP, NDF, ADF) and ruminal degradability of the dry matter and NDF. The treatments were: T1 - in natura residue (IN); T2 - residue submitted to the pressure and steam treated (127ºC/1,5 kgf/cm²/35"; PS); T3 - 4% sodium hydroxide treated residue (four 24 hours; NaOH); T4 - 3% urea treated residue (for 28 days; U); T5 - 4% NaOH +3% urea treated residue (NaOH/U); T6 - pressure and steam + 4% NaOH treated residue (PS/NaOH); T7 - pressure and steam + 3% urea treated residue (PS/U). The results obtained in the chemical composition can allow concluding that combined treatments improved the nutritive value of the residue, as the NaOH/U treatment showed better results of CP, NDF, ADF. In the degradability experiment, it may be concluded that PS, U, NaOH/U, PS/NaOH and PS/U treatments were efficient in increasing effective degradability of DM, also resulted higher dry matter soluble fraction (a) and lower insoluble potentially degradable fraction (b). The treatments U, PS/NaOH and PS/U had higher values of effective degradability of NDF and higher soluble fraction (a). The combined treatments increased the degradability and nutritive value of cotton textile mill waste, and combined treatments with urea had the better results.

Com objetivo de avaliar possibilidades de melhorar o valor nutritivo e a degradabilidade do resíduo de lixadeira do algodão utilizando tratamento biológico de bioconversão com cogumelo Pleurotus sajor-caju, conduziu-se este experimento nos Departamentos de Zootecnia e Biologia da UFLA, Lavras/MG, no período de julho de 2002 a janeiro de 2003. Realizou-se ensaio de produção do cogumelo Pleurotus sajor-caju em dois substratos diferentes (C1 e C2) compostos basicamente de resíduo de lixadeira; após a produção, submeteu-se o resíduo in natura e resultante dos tratamentos C1 e C2 à análise bromatológica e ensaio de degradabilidade de matéria seca e fibra em detergente neutro. Em relação ao resíduo in natura, os tratamentos mostraram-se eficientes em reduzir a fração fibra em detergente neutro e fibra em detergente ácido de 95,24% para 81,11% e 71,21% para fibra em detergente neutro e de 91,16% para 76,85% e 71,14% para fibra em detergente ácido, respectivamente, para C1 e C2. Os tratamentos aumentaram a degradabilidade efetiva da matéria seca e da fibra em detergente neutro do resíduo de lixadeira de algodão de 40,87% para 60,55% e 56,05% e de 44,15% para 65,42% e 67,83%, respectivamente. The objective of the experiment was to evaluate the bio-conversion treatment to enhance the nutritional value and degradability of cotton textile mill waste, using the fungi Pleurotus sajor-caju. The experiment was conducted at the Departments of Biology and Animal Science of the Universidade Federal de Lavras (UFLA), between July 2002 and January 2003. Bio-conversion was induced by the use of the residue as the main component in a substrate bed for cultivation of edible mushrooms (C1 and C2). In comparison to the untreated cotton textile mill waste, two bio-conversion alternatives by Pleurotus sajor-caju were tested. After mushroom production, samples of the treated material were submitted to in situ degradability tests and chemical composition. Results indicated that C1 and C2 treatments decreased fibrous fractions (ADF and NDF) and increased CP of cotton textile mill waste, improving the chemical composition. C1 and C2 treatments also resulted in an increased of soluble fraction (a), the degradation rate (c), and decreased insoluble potential degradable fraction (b); increasing effective degradability of DM and NDF of cotton textile mill waste.

The world production of cement has greatly increased in the past 10 years. This trend is the most significant factor affecting technological development and the updating of manufacturing facilities in the cement industry. Existing technology for the production of cement clinker is ecologically damaging; it consumes much energy and natural resources and also emits pollutants. A new approach to the production of blended or high-volume mineral additive (HVMA) cement helps to improve its ecological compatibility. HVMA cement technology is based on the intergrinding of portland cement clinker, gypsum, mineral additives, and a special complex admixture. This new method increases the compressive strength of ordinary cement, improves durability of the cement-based materials, and - at the same time - uses inexpensive natural mineral additives or industrial by-products. This improvement leads to a reduction of energy consumption per unit of the cement produced. Higher strength, better durability, reduction of pollution at the clinker production stage, and decrease of landfill area occupied by industrial by-products, all provide ecological advantages for HVMA cement.

The paper presents several applications of geosynthetics, geocomposites and industrial by-products in different areas of geo-engineering. Geosynthetics and geocomposites have been used for more than 30 years, and lately more and more. Application of industrial by-products and other alternative materials, such as liners, filters or some other parts of environmental geo-constructions, has several advantages, among which the most important is a considerable money-saving. Examples of these materials are: paper industry waste pulp, compost, some types of ash, components of flysh formations, materials gained by excavations, mineral/polymer mixtures, and waste stone dust.

RESUMEN: Se han realizado grandes avances en el campo de investigación del autosanado de mez-clas asfálticas mediante inducción magnética con partículas metálicas como aditivos, cuyo calentamiento permite reparar sus propias fisuras. Se ha demostrado que esta tecno-logía permite incrementar la vida útil de las carreteras; sin embargo, su alto coste en comparación con otras prácticas de mantenimiento tradicional debido al precio de las partículas metálicas vírgenes hace que esta solución no sea atractiva en términos de in-versión. En este contexto, la presente tesis doctoral tiene por objeto conseguir que este proceso sea económicamente viable y ambientalmente amigable. Para ello, en primer lu-gar, se realizó una búsqueda intensiva de subproductos industriales para reemplazar tan-to las partículas metálicas como los áridos naturales de las mezclas asfálticas. Estos sub-productos incluyeron residuos de procesos de granallado y mecanizado, escorias y are-nas de desmoldeo. La incorporación de estos materiales dio lugar a una serie de mezclas alternativas que se sometieron a un ensayo de rotura-sanado-rotura para determinar su capacidad de autosanado. Los resultados obtenidos a este respecto probaron que los subproductos se calentaban adecuadamente, dando lugar a ratios de sanado satisfacto-rios en comparación con los asociados a las mezclas de referencia tipo hormigón asfáltico (AC-16). Una vez realizada esta parte experimental, se procedió a abordar el modelado numérico del proceso de autosanado de estas mezclas mediante técnicas estadísticas, pues se detectó una carencia de estudios de este tipo en la literatura. La combinación de análisis clúster y modelos de regresión sirvió para reproducir el comportamiento experi-mental de las mezclas en laboratorio con precisión. A partir de ahí, se pudo determinar la cantidad óptima de subproductos industriales y tiempo necesarios para conseguir que el proceso de autosanado fuese tan eficiente como fuera posible. Por último, como respues-ta a la falta de investigaciones orientadas a validar el comportamiento mecánico a largo plazo de mezclas autosanables con subproductos industriales, se llevó a cabo un ensayo uniaxial de fatiga sobre las muestras experimentales y de referencia. Los resultados deri-vados de este test permitieron identificar una ausencia de diferencias estadísticamente significativas entre la respuesta a fatiga de las mezclas experimentales y las de referen-cia. Por tanto, retomando el punto de partida sobre el que se asienta la tesis, se concluyó que la tecnología de autosanado con residuos industriales es una solución sostenible para incrementar la vida útil de mezclas asfálticas, contribuyendo a la economía circular me-diante diversos beneficios económicos y ambientales. ABSTRACT: There have been great advances in the field of self-healing asphalt mixtures by magnetic induction, whereby metal particles are heated to enable the reparation of cracks. This technology has been found to increase the life expectancy of roads; however, its high cost in comparison with traditional maintenance practices due to the price of virgin met-al particles still makes it unattractive in terms of investment. In this context, this PhD thesis aims at making this process economically viable and environmentally efficient. To this end, first was conducting a thorough search for industrial by-products to replace both metal particles and natural aggregates in the design of asphalt mixtures. These by-products included sand blasting wastes, stainless shot wastes and polished wastes as metal particles, as well as other inert by-products as a substitute for natural aggregates. The incorporation of these materials resulted in a series of alternative mixtures that were subject to a break-heal-break test to determine their self-healing capacity. The results obtained in this respect proved that the by-products were heated adequately, leading to satisfactory healing ratios compared with those associated with an asphalt concrete ref-erence mixture (AC-16). Once this experimental part was carried out, next was address-ing the numerical modelling of the self-healing process of these mixtures through statis-tical techniques, since a research gap was found in this regard in the literature. The com-bination of cluster analysis and regression models served to replicate the experimental behavior of the mixtures in the laboratory with accuracy. From there, the optimal amount of industrial by-products and time required to make the self-healing process as efficient as possible were determined. Finally, as a response to the lack of investigations devoted to validating the long-term mechanical performance of self-healing asphalt mix-tures with industrial by-products, the experimental and reference mixtures were subject to a uniaxial fatigue test. The results derived from this experiment enabled identifying an absence of statistically significant differences between the fatigue response of exper-imental and reference mixtures. Therefore, returning to the premise on which the PhD thesis was based, the self-healing technology with industrial by-products was concluded to be a sustainable solution to increase the lifetime of asphalt mixtures, thereby contrib-uting to circular economy through multiple economic and environmental benefits. Al Ministerio de Economía y Competitividad por financiar el estudio de esta tesis mediante la beca de Formación del Personal Investigación (BES-2017-079882) en el seno del proyecto Desarrollo y optimización del Sanado por Inducción de Mezclas Asfálticas que Incluyen Materiales Alternativos y tecnologías Sostenibles (SIMA+) (BIA2016-77372-R).

Recently, chemical soil stabilizations are actively adopted for the improvement of the soft ground on which the road and the foundation for offshore structures will be constructed. The industrial by-products such as gypsum, coal ashes, blastfurnace slag and basic oxygen furnace slag can be used effectively for the soil stabilization. In this paper, the characteristics of soil stabilizations with various industrial by-products are discussed from the viewpoints of the types of reaction products which are responsible for the development of strength in the stabilized soils.

This study evaluated the mechanical characteristics and durability of porous concrete produced with a cementless binder based on ground granulated blast furnace slag (BFS), fly ash (FA) and flue gas desulfurization gypsum (CP). As a result, the void ratio was increased slightly from the target void ratio, by 1.12-1.42 %. Through evaluating the compressive strength, it was found that the compressive strength of porous concrete with cementless binder decreased in comparison to the compressive strength of porous concrete with ordinary Portland cement (OPC), but the difference was insignificant, at 0.6-1.4 MPa. Through the freeze-thawing test to evaluate the durability, it was found that the relative dynamic elastic modulus of porous concrete with cementless binder decreased to 60 % or less at 80 cycles. The result of the chemical resistance test showed that the mass reduction rate was 12.3 % at 5 % HCl solution, and 12.7 % at 12.3 and 5 % H2SO4 solutions.

Magazine article onNew Environmentally friendly and Durable conCrete, integrating industrial by-products and hybrid systems, for civil, industrial and offshore applications.

Magazine article on New Environmentally friendly and Durable conCrete, integrating industrial by-products and hybrid systems, for civil, industrial and offshore applications.