Bioenergy and climate change mitigation : an assessment

Date of Acceptance: 08/05/2014 Acknowledgements The authors are indebted to Julia Römer for assisting with editing several hundred references. Helmut Haberl gratefully acknowledges funding by the Austrian Academy of Sciences (Global Change Programme), the Austrian Ministry of Science and Research (BMWF, proVision programme) as well as by the EU-FP7 project VOLANTE. Carmenza Robledo-Abad received financial support from the Swiss State Secretariat for Economic Affairs.

Nitrogen removal and sustainability of vertical flow constructed wetlands for small scale wastewater treatment

The challenge for wastewater professionals is to design and operate treatment processes that support human well being and are environmentally sensitive throughout the life-cycle. This research focuses on one technology for small-scale wastewater treatment: the vertical flow constructed wetland (VFCW), which is herein investigated for the capacity to remove ammonium and nitrate nitrogen from wastewater. Hydraulic regime and presence/absence of vegetation are the basis for a three-phase bench scale experiment to determine oxygen transfer and nitrogen fate in VFCWs. Results show that 90% NH4+-N removal is achieved in aerobic downflow columns, 60% NO3--N removal occurs in anaerobic upflow columns, and 60% removal of total nitrogen can be achieved in downflow-upflow in-series. The experimental results are studied further using a variably saturated flow and reactive transport model, which allows a mechanistic explanation of the fate and transport of oxygen and nitrogen. The model clarifies the mechanisms of oxygen transport and nitrogen consumption, and clarifies the need for readily biodegradable COD for denitrification. A VFCW is then compared to a horizontal flow constructed wetland (HFCW) for life cycle environmental impacts. High areal emissions of greenhouse gases from VFCWs compared to HFCWs are the driver for the study. The assessment shows that because a VFCW is only 25% of the volume of an HFCW designed for the same treatment quality, the VFCW has only 25-30% of HFCW impacts over 12 impact categories and 3 damage categories. Results show that impacts could be reduced by design improvements. Design recommendations are downflow wetlands for nitrification, upflow wetlands for denitrification, series wetlands for total nitrogen removal, hydraulic load of 142 L/m2d, 30 cm downflow wetland depth, 1.0 m upflow wetland depth, recycle, vegetation and medium-grained sand. These improvements will optimize nitrogen removal, minimize gaseous emissions, and reduce wetland material requirements, thus reducing environmental impact without sacrificing wastewater treatment quality.

Sustainability analysis in the mining sector: a case study on new recycling technologies for sulphidic mine residues valorisation

Research has demonstrated that mining activities can cause serious impacts on the environment, as well as the surrounding communities, mainly due to the unsafe storage of mine tailings. This research focuses on the sustainability assessment of new technologies for the recovery of metals from mine residues. The assessment consists in the evaluation of the environmental, economic, and social impacts through the Life Cycle based methods: Life Cycle Assessment (LCA), Life Cycle Costing (LCC), and Social Life Cycle Assessment (SLCA). The analyses are performed on the Mondo Minerals bioleaching project, which aim is to recover nickel and cobalt from the Sotkamo and Vuonos mine tailings. The LCA demonstrates that the project contributes to the avoided production of nickel and cobalt concentrates from new resources, hence reducing several environmental impacts. The LCC analysis shows that the company’s main costs are linked to the bioleaching process, caused by electricity consumption and the chemicals used. The SLCA analyses the impacts on three main stakeholder categories: workers, local community, and society. The results demonstrated that a fair salary (or the absence of it) impacts the workers the most, while the local community stakeholder category impacts are related to the access to material resources. The health and safety category is the most impacted category for the society stakeholder. The environmental and economic analyses demonstrate that the recovery of mine tailings may represents a good opportunity for mine companies both to reduce the environmental impacts linked to mine tailings and to increase the profitability. In particular, the project helps reduce the amounts of metals extracted from new resources and demonstrates that the use of the bioleaching technology for the extraction of metals can be economically profitable.

Multi-performance assessment of a masonry building with a sustainable RC-Framed Skin

Questa tesi si propone di fornire un approccio multidisciplinare per la valutazione delle prestazioni di una tipologia di intervento sostenibile che consiste in un telaio in calcestruzzo armato (RCFramed skin) per la ristrutturazione integrata di edifici esistenti. Viene fornita una descrizione preliminare di tale tecnologia, con particolare attenzione al miglioramento simultaneo delle prestazioni strutturali (sismiche), non strutturali (energetiche) e alle questioni relative alla limitazione dell'invasività e dell'interruzione dell'uso della costruzione. La valutazione delle prestazioni dell'edificio nelle configurazioni pre e post intervento è effettuata, principalmente in termini di capacità sismica, ma anche del comportamento termo-igrometrico. In particolare, i benefici ottenuti sia dal punto di vista strutturale che energetico sono valutati con riferimento a tre diverse città appartenenti a tre differenti zone sismiche e climatiche. La fattibilità e la sostenibilità dell'intervento di adeguamento proposto sono indagate attraverso una valutazione LCA(Life Cycle Assessment) per l'impatto ambientale e LCC(Life Cycle Cost) per l’analisi economica. Infine, viene proposto un metodo per facilitare la selezione della soluzione di intervento ottimale per ogni sito, combinando l'aspetto strutturale con quello energetico, di impatto ambientale ed economico.

Lifecycle assessment of fuel ethanol from sugarcane in Brazil

This paper presents the lifecycle assessment (LCA) of fuel ethanol, as 100% of the vehicle fuel, from sugarcane in Brazil. The functional unit is 10,000 km run in an urban area by a car with a 1,600-cm(3) engine running on fuel hydrated ethanol, and the resulting reference flow is 1,000 kg of ethanol. The product system includes agricultural and industrial activities, distribution, cogeneration of electricity and steam, ethanol use during car driving, and industrial by-products recycling to irrigate sugarcane fields. The use of sugarcane by the ethanol agribusiness is one of the foremost financial resources for the economy of the Brazilian rural area, which occupies extensive areas and provides far-reaching potentials for renewable fuel production. But, there are environmental impacts during the fuel ethanol lifecycle, which this paper intents to analyze, including addressing the main activities responsible for such impacts and indicating some suggestions to minimize the impacts. This study is classified as an applied quantitative research, and the technical procedure to achieve the exploratory goal is based on bibliographic revision, documental research, primary data collection, and study cases at sugarcane farms and fuel ethanol industries in the northeast of SA o pound Paulo State, Brazil. The methodological structure for this LCA study is in agreement with the International Standardization Organization, and the method used is the Environmental Design of Industrial Products. The lifecycle impact assessment (LCIA) covers the following emission-related impact categories: global warming, ozone formation, acidification, nutrient enrichment, ecotoxicity, and human toxicity. The results of the fuel ethanol LCI demonstrate that even though alcohol is considered a renewable fuel because it comes from biomass (sugarcane), it uses a high quantity and diversity of nonrenewable resources over its lifecycle. The input of renewable resources is also high mainly because of the water consumption in the industrial phases, due to the sugarcane washing process. During the lifecycle of alcohol, there is a surplus of electric energy due to the cogeneration activity. Another focus point is the quantity of emissions to the atmosphere and the diversity of the substances emitted. Harvesting is the unit process that contributes most to global warming. For photochemical ozone formation, harvesting is also the activity with the strongest contributions due to the burning in harvesting and the emissions from using diesel fuel. The acidification impact potential is mostly due to the NOx emitted by the combustion of ethanol during use, on account of the sulfuric acid use in the industrial process and because of the NOx emitted by the burning in harvesting. The main consequence of the intensive use of fertilizers to the field is the high nutrient enrichment impact potential associated with this activity. The main contributions to the ecotoxicity impact potential come from chemical applications during crop growth. The activity that presents the highest impact potential for human toxicity (HT) via air and via soil is harvesting. Via water, HT potential is high in harvesting due to lubricant use on the machines. The normalization results indicate that nutrient enrichment, acidification, and human toxicity via air and via water are the most significant impact potentials for the lifecycle of fuel ethanol. The fuel ethanol lifecycle contributes negatively to all the impact potentials analyzed: global warming, ozone formation, acidification, nutrient enrichment, ecotoxicity, and human toxicity. Concerning energy consumption, it consumes less energy than its own production largely because of the electricity cogeneration system, but this process is highly dependent on water. The main causes for the biggest impact potential indicated by the normalization is the nutrient application, the burning in harvesting and the use of diesel fuel. The recommendations for the ethanol lifecycle are: harvesting the sugarcane without burning; more environmentally benign agricultural practices; renewable fuel rather than diesel; not washing sugarcane and implementing water recycling systems during the industrial processing; and improving the system of gases emissions control during the use of ethanol in cars, mainly for NOx. Other studies on the fuel ethanol from sugarcane may analyze in more details the social aspects, the biodiversity, and the land use impact.

Greenhouse gas emissions and energy balance of palm oil biofuel

The search for alternatives to fossil fuels is boosting interest in biodiesel production. Among the crops used to produce biodiesel, palm trees stand out due to their high productivity and positive energy balance. This work assesses life cycle emissions and the energy balance of biodiesel production from palm oil in Brazil. The results are compared through a meta-analysis to previous published studies: Wood and Corley (1991) [Wood BJ, Corley RH. The energy balance of oil palm cultivation. In: PORIM intl. palm oil conference agriculture; 1991.], Malaysia; Yusoff and Hansen (2005) [Yusoff S. Hansen SB. Feasibility study of performing an life cycle assessment on crude palm oil production in Malaysia. International Journal of Life Cycle Assessment 2007;12:50-8], Malaysia; Angarita et al. (2009) [Angarita EE, Lora EE, Costa RE, Torres EA. The energy balance in the palm oil-derived methyl ester (PME) life cycle for the cases in Brazil and Colombia. Renewable Energy 2009;34:2905-13], Colombia; Pleanjai and Gheewala (2009) [Pleanjai S. Gheewala SH. Full chain energy analysis of biodiesel production from palm oil in Thailand. Applied Energy 2009;86:S209-14], Thailand; and Yee et al. (2009) [Yee KF, Tan KT, Abdullah AZ, Lee la. Life cycle assessment of palm biodiesel: revealing facts and benefits for sustainability. Applied Energy 2009;86:S189-96], Malaysia. In our study, data for the agricultural phase, transport, and energy content of the products and co-products were obtained from previous assessments done in Brazil. The energy intensities and greenhouse gas emission factors were obtained from the Simapro 7.1.8. software and other authors. These factors were applied to the inputs and outputs listed in the selected studies to render them comparable. The energy balance for our study was 1:5.37. In comparison the range for the other studies is between 1:3.40 and 1:7.78. Life cycle emissions determined in our assessment resulted in 1437 kg CO(2)e/ha, while our analysis based on the information provided by other authors resulted in 2406 kg CO(2)e/ha, on average. The Angarita et al. (2009) [Angarita EE, Lora EE, Costa RE, Torres EA. The energy balance in the palm oil-derived methyl ester (PME) life cycle for the cases in Brazil and Colombia. Renewable Energy 2009:34:2905-13] study does not report emissions. When compared to diesel on a energy basis, avoided emissions due to the use of biodiesel account for 80 g CO(2)e/MJ. Thus, avoided life Cycle emissions associated with the use of biodiesel yield a net reduction of greenhouse gas emissions. We also assessed the carbon balance between a palm tree plantation, including displaced emissions from diesel, and a natural ecosystem. Considering the carbon balance outcome plus life cycle emissions the payback time for a tropical forest is 39 years. The result published by Gibbs et al. (2008) [Gibbs HK, Johnston M, Foley JA, Holloway T, Monfreda C, Ramankutty N, et al., Carbon payback times for crop-based biofuel expansion in the tropics: the effects of changing yield and technology. Environmental Research Letters 2008;3:10], which ignores life cycle emissions, determined a payback range for biodiesel production between 30 and 120 years. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.

Análise de ciclo de vida de duas soluções de ETICS

Dissertação de natureza científica para obtenção do grau de mestre em Engenharia Civil

Sustentabilidade na reablitação urbana

A indústria da construção é um setor com grande impacto na economia, no Produto Interno Bruto (PIB) e ainda em postos de trabalho diretos e indiretos. No entanto, é um dos setores com maior impacte ambiental. Com a crise económica e financeira que o país atravessa, este setor foi um dos mais afetados, contribuindo para o aumento do desemprego visto tratar-se do setor com maior taxa de empregabilidade. Concomitantemente, ocorre saturação do mercado com a construção nova e desertificação dos centros urbanos com a degradação das habitações. Assim, como impulsionador da economia, surge a aposta na reabilitação do parque edificado que, com a legislação em vigor e com os incentivos dados pela tutela tem tudo para impulsionar o setor. Sabendo que a indústria da construção é um dos setores com maiores impactes ambientais, faz todo o sentido reabilitar-se de uma forma mais sustentável. Aplicando os princípios da sustentabilidade a todo o ciclo de vida do edifício, conseguimos reduzir os recursos na fase de construção (resíduos de construção) e na fase de exploração (consumo de energia e de água). Podemos ainda reduzir os custos de energia para climatização ao termos em conta a orientação do edifício e a envolvente, os recursos naturais e aplicando tecnologias solares passivas. Assim, ao aplicarmos os princípios da construção sustentável na reabilitação urbana podemos diminuir os impactes ambientais, a produção de CO2, as emissões de gases com efeito de estufa, os resíduos de construção e a área impermeabilizada.

Sustainability and economic evaluation of microalgae grown in brewery wastewater

This article evaluates the sustainability and economic potential of microalgae grown in brewery wastewater for biodiesel and biomass production. Three sustainability and two economic indicators were considered in the evaluation within a life cycle perspective. For the production system the most efficient process units were selected. Results show that harvesting and oil separation are the main process bottlenecks. Microalgae with higher lipid content and productivity are desirable for biodiesel production, although comparable to other biofuel’s feedstock concerning sustainability. However, improvements are still needed to reach the performance level of fossil diesel. Profitability reaches a limit for larger cultivation areas, being higher when extracted biomass is sold together with microalgae oil, in which case the influence of lipid content and areal productivity is smaller. The values of oil and/or biomass prices calculated to ensure that the process is economically sound are still very high compared with other fuel options, especially biodiesel.

Sustainability Evaluation of Biodiesel Produced from Microalgae Chlamydomonas sp Grown in Brewery Wastewater

This study performs a sustainability evaluation of biodiesel from microalga Chlamydomonas sp. grown in 20 % (v/v) of brewery’s wastewater, blended with pentose sugars (xylose, arabinose or ribose resulting from the hydrolysis of brewer’s spent grains (BSG). The life cycle steps considered for the study are: microalgae cultivation, biomass processing and lipids extraction at the brewery site, and its conversion to biodiesel at a dedicated external biofuel’s plant. Three sustainability indicators (LCEE, FER and GW) were considered and calculated using experimental data. Literature data was used, whenever necessary, to complement life cycle data, thus allowing a more accurate sustainability evaluation. A comparative analysis of the biodiesel life cycle steps was also conducted, with the main goal of identifying which steps need to be improved. Results show that biomass processing, especially cell harvesting, microalgae cultivation, and lipids extraction are the main process bottlenecks. It is also analysed the influence on the microalgae biodiesel sustainability of adding each pentose sugar to the cultivation media, concluding that it strongly influences the biomass and lipid productivity. In particular, the addition of xylose is preferable in terms of lipid productivity, but from a sustainability point of view, ribose is the best, though the difference from xylose is not significant. Nevertheless, culture without pentose addition presents the best sustainability results.

Sustentabilidade na construção metálica

O desenvolvimento sustentável é um dos grandes desafios dos nossos tempos com inúmeras consequências em várias áreas da nossa sociedade. É uma questão abrangente e essencial para a sobrevivência do modo de vida tal como o conhecemos actualmente. A construção sustentável tem um papel muito importante no desenvolvimento, não só ao nível económico mas também social e cultural. Embora não contemple a energia incorporada, a avaliação do ciclo de vida (ACV), no sector da construção, é um dos métodos mais comuns para avaliar o nível de sustentabilidade. Este trabalho visa os metais como uma das mais promissoras e actuais respostas do sector da construção às crescentes preocupações em relação ao desenvolvimento sustentável. O ferro e derivados são normalmente a base das construções metálicas, residindo no seu potencial de reutilização e reciclagem um dos seus principais factores de sustentabilidade. As estruturas metálicas apresentam características especificas que se coadunam com os requisitos da construção sustentável e que tornam este tipo de construção extremamente versátil e interessante. Neste trabalho, é efectuada uma abordagem sobre a construção metálica ao longo de três partes. A primeira parte é constituída por uma introdução histórica ao ferro e seus derivados enunciando exemplos de construções até aos nossos dias, e pela classificação dos vários tipos de metais e ligas metálicas. Na segunda parte, é abordado o conceito de sustentável e o seu enquadramento no sector da construção, e é feita uma introdução à metodologia de avaliação de ciclo de vida. Na terceira parte, é abordado um exemplo prático de uma estrutura metálica em que são elaboradas e comparadas três soluções. Na origem da diversidade dos elementos comparativos estão o tipo de aço, a origem da energia utilizada no seu fabrico e o tipo de solução técnica adoptada. O objectivo deste trabalho é compreender as repercussões do conceito de sustentabilidade no sector da construção, e desenvolver um método simplificado de avaliação dos impactos ambientais e económicos de soluções metálicas.

Sustainability of systems interoperability in dynamic business networks

Dissertação para obtenção do Grau de Doutor em Engenharia Electrotécnica e de Computadores

Qualitative risk assessment during polymer mortar test specimens preparation - methods comparison

Polymer binder modification with inorganic nanomaterials (NM) could be a potential and efficient solution to control matrix flammability of polymer concrete (PC) materials without sacrificing other important properties. Occupational exposures can occur all along the life cycle of a NM and “nanoproducts” from research through scale-up, product development, manufacturing, and end of life. The main objective of the present study is to analyse and compare different qualitative risk assessment methods during the production of polymer mortars (PM) with NM. The laboratory scale production process was divided in 3 main phases (pre-production, production and post-production), which allow testing the assessment methods in different situations. The risk assessment involved in the manufacturing process of PM was made by using the qualitative analyses based on: French Agency for Food, Environmental and Occupational Health & Safety method (ANSES); Control Banding Nanotool (CB Nanotool); Ecole Polytechnique Fédérale de Lausanne method (EPFL); Guidance working safely with nanomaterials and nanoproducts (GWSNN); Istituto Superiore per la Prevenzione e la Sicurezza del Lavoro, Italy method (ISPESL); Precautionary Matrix for Synthetic Nanomaterials (PMSN); and Stoffenmanager Nano. It was verified that the different methods applied also produce different final results. In phases 1 and 3 the risk assessment tends to be classified as medium-high risk, while for phase 2 the more common result is medium level. It is necessary to improve the use of qualitative methods by defining narrow criteria for the methods selection for each assessed situation, bearing in mind that the uncertainties are also a relevant factor when dealing with the risk related to nanotechnologies field.

Sustainability education in PBL education: the case study of IEM-UMINHO

Sustainability-related skills are becoming more and more relevant for a proficient and professional engineering practice. Industrial engineers in particular, given their broad field of intervention and being at the heart of industrial activity, hold a great deal of potential and responsibility in providing and delivering best industrial practices, that support enhanced industrial systems and products. Therefore making a real contribution in generating wealth and income for all the companies’ stakeholders, including local communities, as well as adding up to more sustainable ecosystems. Previous work by the authors focused on studying the inclusion of this subject on the education of industrial engineers, especially through active-learning methodologies, as well as presenting results on the use of one such approach. The study conducted tried to identify the impacts on sustainability learning using a given specific activity, i.e. a workshop on industrial ecology, held in the 2014/2015 academic year on the Integrated MSc degree on Industrial Engineering and Management at the University of Minho, Portugal. The study uses content analysis of student teams’ reports for two consecutive academic years. The former did not include one such workshop, while the latter did. The Fink taxonomy was used in the discussion of results and reflection. The study outcomes aimed at supporting decision making on worthiness of investment on similar education instruments for sustainability competency development. Some results of the study highlight that: (1) the workshop seem to globally have a positive contribution on the sustainability learning; (2) a number of dimensions of the Life cycle design strategy wheel was developed, but the approach was not broadly used, (3) There was a mismatch on the workshop schedule; (4) students enjoy the workshop; (5) a clearer endorsement on relevance of this aspect is required. Suggestions for future work are also issued.

The importance of the category of consciousness and education for sustainability in methodologies for eco‐efficiency in school buildings

This document reports the importance of the category of consciousness and education for sustainability in the school environment. Education in school has a potential to make the benefits of the building construction visible for society and media, showing to the students, parents and communities how sustainability in built environment could improve the people life in economic, social and environment aspects. Thus, this paper addresses the main events related to sustainability, such as the Stockholm Conference, the Brundtland report, United Nations Conference on Environment and Development (UNCED) and Agenda 21, until reaching the necessity of the elaboration of Methodologies for environmental assessment of building, and later, the development of the specific methodologies according to the buildings. It is also described some examples of sustainability in schools in Germany, Finland and Italy and what kind of sustainable systems those countries are currently using.