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- THERMALLY MODIFIED PINE BOARDS - AN ENVIRONMENTAL COMPARISON OF PORTUGUESE AND SPANISH CASE STUDIESPublication . Ferreira, José; Herrera, René; Esteves, Bruno; Domingos, IdalinaThermal modification is a well-known process to improve some of the most important wood properties by using heat in a low oxygen environment. The main changes are the reduc-tion of equilibrium moisture content, increased dimensional stability and increased resistance against fungi [1]. As no chemical compounds or other extraneous constituents are added to wood in the process, it has a potential of being a green building material. At the moment, there are only two companies in Portugal [2] and one company in Spain producing modified wood by heat treatment [3]. The main aim of this study is to compare the environmental profile of thermally modified pine boards produced by a Portuguese and a Spanish company using the Life Cycle Assess-ment (LCA) methodology described in ISO 14040 [4] and ISO 14044 [5] standards and Product Category Rules for preparing an environmental product declaration (EPD) for Construction Products and Construction Services [6]. For an EPD that covers a “cradle to gate” the declared unit is applicable instead of func-tional unit and in this case is 1 m3 of thermally modified pine boards. The system boundary for the product system is represented in a simplified way in Fig.1. Fig. 1 The system boundaries of the study As the sawing and planning processes of the product system delivers the products (pine boards) and co-products (wood residues – bark, sawdust and chips), that can be used as raw material for other product system, the environmental burdens of this process are allocated to product and co-products based in its economic value. The datasets for the products and processes included in the system boundaries are compa-nies’ data and are related to the year 2014. The thermo-treatment used was Thermo I (intense treatment) to allow treated pine boards to be used in exterior decks or cladding. The inventory analysis and, subsequently, the impact analysis have been performed using the LCA software SimaPro 8.1.0.60 [7] and associated databases and methods. The method chosen for impact assessment was EPD-2013 V1.01 [8]. The impact categories considered were: acidification (AC), eutrophication (EU), global warming (GWP 100a), photochemical oxidation (PO), ozone layer depletion (ODP) and abiotic depletion (AD). Fig. 2 shows the result of comparative environmental profiles of the thermally modified pine boards produced by the companies in this study. Figure 1: Comparative profiles of the thermally modified pine boards. Acronyms: AC (acidification); EU (eu-trophication), GWP 100a (global warming), PO (photochemical oxidation), ODP (ozone layer depletion) and AD (abiotic depletion) The contribution of Portuguese and Spanish treated boards to climate change (CC), is al-most equal. The Spanish treated boards are better than Portuguese for acidification (65%), eutrophication (52%), ozone layer depletion (87%) and abiotic depletion (61%) and the oppo-site is true for photochemical oxidant formation (66%).
- Increase of calorific value of two important feedstocks by mild torrefactionPublication . Domingos, Idalina; Ferreira, José; Cruz-Lopes, Luísa; Esteves, BrunoIn the last decades efforts have been made to replace fossil fuels by more sustainable feedstocks for the production of energy. A way to increase the travelable distance of this feedstock is to increase its energy content. The objective of this work was to study the increase in the calorific value of two of the most important wood species in the central region of Portugal, a softwood, (Pinus pinaster Ait) and a hardwood (Eucalyptus globulus Labill.), by mild torrefaction. The treatment was made in an oven during 2 -24 hours and temperatures from 170ºC to 190ºC. Calorific value and insoluble lignin were determined. Results show that there is an increase in the HHV (High Heating Value) of both pine and eucalypt samples (higher in eucalypt) and that the increase is higher for higher treatment times. A good correlation between the amount of lignin and the HHV was found.
- Environmental profile of the electricity supplied in Portugal by the main suppliersPublication . Ferreira, José; Esteves, Bruno; Cruz-Lopes, Luísa; Domingos, IdalinaThe main aim of this study was to assess and compare the environmental profile of 1 KWh of electricity supplied during 2014 by the four main electricity selling companies in Continental Portugal. The study was elaborated based on Life Cycle Assessment methodology and the method chosen for environmental impact assessment was EPD2013. The results show that the ENDESA´s electricity was the worst in terms of acidification, eutrophication, global warming, photochemical oxidation and ozone layer depletion while IBERDROLA´s electricity was the best for those impact categories and the worst in terms of abiotic depletion. Including in the study, the net electricity fed into the Portuguese and UCTE grid at the high voltage level, the conclusion is that the electricity at Portuguese grid presents the worst performance in terms of acidification, global warming and photochemical oxidation while the electricity at UCTE grid presents the worst performance in terms of eutrophication and ozone layer depletion.
- State of the art of industrial wood protection in PortugalPublication . Nunes, Lina; Carmo, Júlia; Vicente, José; Esteves, BrunoThis work intended to give a perspective of industrial wood protection in Portugal. A survey was made of the companies treating wood mainly for use classes 3 and 4 such as autoclave treatments with biocides and wood modification procedures. Currently there are 23 companies with 33 production plants with an autoclave installed for wood preservation by impregnation. There are also two companies producing modified wood by thermal treatment. Most of the plants are located in the central and northern regions of Portugal. The leading preservation chemicals used in Portugal are Tanalith E and Celcure brands. The main wood species used in all companies is Pinus pinaster from local producers. The products commercialized by the treating companies are diverse: pre-fabricated houses, garden furniture and playgrounds, decks, poles, stakes, and sawn wood. Modified wood producers sell mostly decks and cladding. Considerable changes are expected in the next few years due to the requirements of European Directives and the typical constraints of the Portuguese market.
- Design of products to honor people post mortemPublication . Martins, João; Simões, JoséThe cemeterial units, are places of social practices of everyday life and worship and the tomb where nostalgia can be externalized and the memory of the deceased revered. In Western societies we can find a category of artifacts meant to evoke the memory or honor the dead. In this paper we we mention three examples of products that enabled a reflection on the concepts that gave rise to their ways, and that risks to fit them into a new "material culture", in that it may have created a break with the traditional system codes and standards shared by companies, and its manifestations in relation to the physical creation of this category of products. This work offers a reflection on the Design Products.What probably makes it special is the field where it is located: the design of products in one post mortem memory. Usually made of granite rock or marble, have the form of plate or tablet, open book or rolled sheet. On one side have a photograph of the person who intend to honor and inscriptions. The thought of inherent design of this work put on one side the intricate set of emotions that this type of product can generate, and other components more affordable, and concerning the form, function and object interactions with users and with use environments. In the definition of the problem it was regarded as mandatory requirements: differentiation, added value and durability as key objectives.The first two should be manifested in the various components / product attributes. The aesthetic and material/structural durability of product necessarily imply the introduction of qualifying terms and quantitative weights, which positively influence the generation and evaluation of concepts based on the set of 10 principles for the project that originated a matrix as a tool to aid designing products. The concrete definition of a target audience was equally important. At this stage, the collaboration of other experts in the fields of psychology and sociology as disciplines with particular ability to understand individuals and social phenomena respectively was crucial. It was concluded that a product design to honor someone post mortem, should abandon the more traditional habits and customs to focus on identifying new audiences. Although at present it can be considered a niche market, it is believed that in the future may grow as well as their interest in this type of products.
- The Academic-enterprise experiences framework as a guide for design educationPublication . Martins, João; Coelho, Cristina; Oliveira, Marcelo; Pereira, JoãoThe establishment of support platforms for the development of a new culture in design education, in order to achieve both research exploitation and its results, as an approach to the industrial community, challenges higher education institutions to rethink their functioning, divided between investigation on their own initiative or on demand, and its usefulness / practical application. At the same time, through design education, how can they be the engine that aggregates all these frequently antagonistic interests? Polytechnic institutes are predisposed to collaboration and interdisciplinarity. In our course of Technology and Design of Furniture, the availability of a production unit, testing laboratories, and expertise in engineering, design and marketing, encourage the development of a holistic project. In order to develop such knowledge, we adapt three important ways of thinking in designing interactions influenced by the traditional approach, namely, 1) identifying and understanding a design problem, i.e. a market need, 2) defining the design process and knowing what can be used for design education, i.e. opportunities for design education, and 3) sustainability of this framework and design projects' alignment with education in the same field. We explain our approach by arguing from the academicenterprise experiences perspective. This concept is proposed as a way to achieve those three ways of thinking in design education. Then, a set of interaction attributes is defined to explain how engineering and product design education can enhance meaningful relations with manufacturers, stakeholders and society in general. A final discussion is presented with the implications and benefits of this approach. The results suggest that through academic-enterprise partnerships in design, several goals such as students' motivation, product design innovation and potential for knowledge transfer to industries can be achieved.
- Colagem e propriedades mecânicas da madeira de pinheiro tratada termicamentePublication . Esteves, Bruno; Pereira, HelenaO tratamento térmico da madeira permite diminuir a higroscopicidade da madeira, melhorando a sua estabilidade dimensional e a resistência a vários tipos de biodegradação. Utilizando este tratamento é possível atribuir um maior valor acrescentado, permitindo a madeiras menos nobres a sua utilização no exterior, sem a utilização de qualquer químico. O tratamento térmico da madeira de pinheiro (Pinus pinaster) foi feito na ausência de oxigénio numa autoclave com uma mistura de ar sobreaquecido e saturado durante 2, 4, 6, 8 e 12 horas à temperatura de 200 ºC. Determinou-se a resistência à colagem, a molhabilidade e a dureza nas secções tangencial e radial, o módulo de elasticidade e a tensão de rotura por flexão estática. A resistência à colagem, utilizando uma cola de acetato de polivinil (PVA) foi determinada de acordo com a norma DS/CEN/TS 13354. Determinou-se a molhabilidade da madeira pelo método do ângulo de contacto usando um goniómetro. A dureza foi medida de acordo com a norma ISO 3350 (1975). O módulo de elasticidade e a tensão de rotura à flexão foram determinados através de um ensaio a três pontos. Verificou-se que a resistência à colagem diminuiu com a intensidade do tratamento térmico. Foi possível obter uma relação aproximadamente linear (R2=0,81) entre a resistência à colagem e a perda de massa devido ao tratamento térmico. Ao mesmo tempo observou-se uma diminuição da molhabilidade da superfície da madeira o que contribui para uma diminuição da resistência à colagem. Em relação às propriedades mecânicas o MOE praticamente não foi afectado enquanto a tensão de rotura diminuiu com a intensidade do tratamento atingindo cerca de menos 30%. A dureza da madeira tratada também diminuiu quer na secção tangencial, quer na radial atingindo uma redução máxima de cerca de 30%.
- Novos métodos de protecção da madeiraPublication . Esteves, Bruno; Pereira, HelenaEm Portugal, a preservação de madeiras para a Classe de risco 4 é feita através da impregnação com produtos de elevada toxicidade. O estudo de métodos alternativos de preservação é crítico para as empresas de preservação de madeira, alarmadas pelas limitações contínuas no uso dos produtos químicos. A modificação da madeira é um processo que melhora as propriedades como a resistência à biodegradação, a estabilidade dimensional, a resistência à radiação ultravioleta, entre outras, produzindo um material novo que no fim do ciclo de vida do produto não apresenta um perigo ambiental superior ao da madeira não tratada. Existem quatro tipos de processos: a modificação térmica, química, da superfície e a impregnação. A modificação térmica é aquela que tem mais sucesso sendo o processo Thermowood o mais utilizado. De entre os outros processos comerciais a acetilação (modificação química) e a furfurilação (modificação por impregnação) também se encontram bem implantados no mercado. De momento ainda nenhum processo de modificação superficial foi industrializado devido ao elevado custo. Neste artigo é feito um resumo dos principais processos de cada tipo de modificação apresentando as melhorias em relação à madeira não tratada, as vantagens e desvantagens de cada processo e a evolução em termos comerciais.
- Technological improvement of Portuguese eucalypt and pine woods by heat treatmentPublication . Esteves, BrunoHeat treatments for technological improvement of wood were made in the presence of air using Eucalyptus globulus. The heat treatment was made using an oven during 2 to 24 h and temperatures of 170 ºC, to 200 ºC. Mass losses increased with treatment time and temperature. Anti Shrinking Efficiency (ASE) between treated and untreated samples was calculated at 35%, 65% and 85% relative humidity for radial and tangential directions. Bending strength and MOE were also determined. Equilibrium moisture content of heat-treated wood decreased by 67%. 87%Radial ASE35% for Tangential ASE35% was usually higher than radial. ASE65% and ASE85% showed behaviour similar to ASE35% but smaller. All ASE values increased with temperature and treatment time. Bending strength and MOE decreased with mass loss.