Experiències en una assignatura optativa no convencional: introducció als nous materials a l'arquitectura

L’assignatura “Introducció de Nous Materials a l’Arquitectura” de 5 crèdits es realitza al segon quadrimestre del pla d’estudis vigents de l’ETSAV per a alumnes matriculats a partir del 5 quadrimestre. Aquesta assignatura es planteja com un “training” prop de la innovació, això és, desenvolupar l’aplicació de nous material a l’arquitectura.Peer Reviewe

Environmental effects of using clay bricks produced with sewage sludge: leachability and toxicity studies

Peer ReviewedPostprint (published version

Ceramic macromembrane for tangento-axial micro- and ultrafiltration water systems

An innovative proposal of tangento-axial filtration based on the concept of macromembrane (large size) is presented in the context of micro- and ultrafiltration ceramic membranes. The macromembrane is made of Al2O3–TiO2 by slip casting. It includes an internal system for rotating the fluid trough a propeller which enhances the tangento-axial filtration. This filtration yields better than the cross-flow filtration in conventional extruded ceramic tubes of small diameter. The reasons are, first, its larger sizes relative to the extruded tubular filters, and second, that it can work at higher pressures, resulting in better operational performance. Furthermore, costs of industrial-scale production could be lower. In this study, the conceptual basis, pilot plant, first experimental results, and proposals for improvement of the system to continue the project are presented.Peer ReviewedPostprint (author's final draft

New ceramic technology for catalysis and the reduction of emissions and particulate pollutants into the atmosphere

Accèssit del "Premio Jaume Blasco a la innovación", atorgat per l'Asociación Española de Ingeniería de Proyectos, AEIPROInternal combustion engines have been causing a lot of pollution, as in their combustion process produce harmful gases such as CO, hydrocarbons, NOx and particulate matter. Environmental requirements on polluting aspects of the transport sector and in motor vehicles especially, and the demand for sustainable technology for the planet, lead to the need to improve the devices for depuration of gaseous and particulate matter emissions. On the other hand, we can not forget the costs of implementing these systems in the automotive sector in a scenario of economic crisis, with increasing offer and declining demand. In this context, we have been working on a project called MEDEA, which aims to achieve a new technology that combines the following parameters: simplicity; reduced cost of implementation; reduced emissions (able to meet Euro 6 regulations and reduce CO2 emissions to 130 g/km); and durability. In this paper we present the development and results of the first phase of this project carried out on behalf of the Chair SEAT.Award-winningPostprint (published version

Incorporation of paper sludge in clay brick formulation : ten years of industrial experience

The large amounts of sewage sludge (11 million tonnes in Europe in 2005) produced in paper manufacturing plants require the introduction of recycling and/or alternative recovery solutions to minimize the amounts of generated waste, such as its use in soil remediation or in the cement industry. A feasible alternative to valorize that waste is the use of paper sludge as raw material in the production of structural ceramic or clay bricks. Previous studies tried to incorporate sewage sludge from different sources into ceramic matrices, unfortunately with little success in the final result for most types of sludge. However, those experiments carried out using as additive sludge from the paper industry succeeded in producing amaterial suitable for the red ceramic industry. In this paper, binary mixtures of clay and paper sludge under different formulations were produced and their physico-chemical properties were studied. Increasing the paper sludge content in the clay mixture provides the material with improved properties regarding its thermal and acoustic insulation, but in turn it decreases its mechanical strength. However, this fragility of the material is compensated by an increased ductility. Regarding metal leaching, the studied ceramics have no environmental restrictions as far as their use as building material is concerned, as the obtained results were virtually identical to those for the blank samples (100% clay). Results showed that the presence of dichloromethane (373.2 µg m-3) and propanone (61.2 µg m-3) in the samples with added sludge was relatively relevant with respect to concentrations in samples made of 100% clay. All monocyclic aromatics detected showed a concentration level far below their odor threshold. In general, thus, it can be concluded that volatile organic compound (VOC) emissions during firing of the new ceramic material do not involve any particular problem. Finally, the experience obtained after more than 10 years of industrial production of this new mixed ceramic product was also analyzed. This analysis allowed confirmation that clay brick productionwith incorporation of paper sludge waste is a feasible solution froma technical point of view. As a key outcome, this fact has helped the reduction in a large proportion the amount of sludge produced by the Spanish paper industry ending up in landfills.Peer ReviewedPostprint (author’s final draft

Comparative study of the performance of three cross-flow ceramic membranes for water treatment

Several tests using water as effluent are used to analyse the performance of three types of microfiltration cross-flow ceramic membranes. Two of these membranes are commercial (Atech and Membralox/US Filter) and the third one is experimental. The main differences between them lie in their chemical composition (different origin of raw materials) and in their manufacturing process. The results presented here show the dominant effect of the filtering and the gel layer. Both are formed during operation acting as equalising agent between the three membranes. The membranes tested have similar performances in cross-flow operation, although permeability rates for the membrane Membralox/US Filter were about 15% higher. This increase might be due to the smoother surface formed by a second filtering ultrafiltration layer (0.01 ìm) of 10 ìm width, which probably contributes to a decrease in the thickness of the gel layer formed during operation. Using specific raw materials (non-industrial) as well as a second ultrafiltration layer improves the results in operation (performances and cleaning intervals). However, they are uneconomical because of the extra costs involved. In conclusion, low-cost membranes can achieve similar results to the commercial and more expensive ones opening up their application to new uses and emergent markets.Peer ReviewedPostprint (published version

Experience on a low cost way to obtain Al-Ti ceramic foams

An experience on a simple process for producing alumina-rutile-mullite ceramic foams by using aqueous particulate slurries is proposed. The sintering process is achieved in one unique thermal process at 1200 ºC in air. The description of the process, physical properties and morphological studies are reported. Microstructure is studied by using confocal optical microscopic technique. The highly active porous foam structure of this ceramic material produced according to the low-cost process presented here could extend its use in a broad range of applications, such as catalytic, biomedical scaffolds, filtering, etc.Peer ReviewedPostprint (published version

Graphene. Part II : processes and feasibility of its production

Ante el descubrimiento del grafeno, un material con propiedades de gran interés tecnológico, la industria busca optimizar sus mecanismos de producción con el objetivo de abordar un mercado para el cual se prevé un gran crecimiento. La síntesis de grafeno puede llevarse a cabo mediante diversos procesos, si bien para cada uno de ellos se pueden advertir diferencias respecto la calidad del producto final. Entre tales procesos, se distinguen dos grupos: aquellos que parten de átomos de carbono para sintetizar grafeno (métodos bottom-up), o aquellos que parten de estructuras más complejas (métodos top-down). En la primera parte de este trabajo se presentó una revisión sobre el estado actual del conocimiento de las propiedades del grafeno y sus aplicaciones posibles. En esta segunda parte se presentan diversas tecnologías para su producción, con el fin de determinar la viabilidad de una planta, desde los puntos de vista técnico y económico. Mediante un análisis multicriterio, se ha seleccionado como tecnología más viable el método de producción basado en la deposición química de vapor. También, se ha estimado la viabilidad económica de un planta que produjera unos 375 m2/año de grafeno monocapa.Postprint (published version

Estudi mecànic comparatiu de tíbies fracturades amb pròtesis Enders i Kunscher

El comportament mecànic de tíbies fracturades i tractades amb pròtesis Enders i Kunscher són estudiades mitjançant la preparació de mostres simulades i l'ús de tècniques pròpies d'assaigs mecànics de materials. Els resultats obtinguts són discutits a la llum dels diferents graus de llibertat mecànica assolida en ambdós sistemes, així com d'experiències clíniques

Experiències en una assignatura optativa no convencional: introducció als nous materials a l'arquitectura

L’assignatura “Introducció de Nous Materials a l’Arquitectura” de 5 crèdits es realitza al segon quadrimestre del pla d’estudis vigents de l’ETSAV per a alumnes matriculats a partir del 5 quadrimestre. Aquesta assignatura es planteja com un “training” prop de la innovació, això és, desenvolupar l’aplicació de nous material a l’arquitectura.Peer Reviewe