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This zipped folder contains the files used to generate the results of this article, submitted to the journal Climatic Change.

Universidade Estadual Paulista (UNESP) ; Pós-graduação em Alimentos e Nutrição - FCFAR ; No presente trabalho, inicialmente foi feito um estudo da Metodologia de Superfície de Resposta (RSM) que tem sido adotada com muita freqüência na otimização com várias aplicações na biotecnologia. Foi feita uma revisão na literatura científica dos conhecimentos existente, onde se priorizou as bases teóricas da RSM que consiste em: trabalho preliminar, onde são determinados as variáveis independentes e seus níveis; seleção do projeto experimental com a previsão e verificação da validade da equação do modelo e, representação gráfica da equação do modelo e determinação das condições ótimas de operação. Em seguida a RSM foi aplicada na otimização de biomassa pela levedura recombinante Pichia pastoris. Pichia pastoris que é uma levedura metilotrófica, geneticamente manipulada para expressar proteínas heterólogas que são de grande valor biotecnologico na pesquisa básica e em usos industriais na produção de grande variedade de proteínas heterólogas. Glicerol quinase (GK; EC 2.7.1.30) é uma enzima chave no metabolismo do glicerol e catalisa glicerol para glicerol-3- fosfato na biossíntese de fosfolípidos. Nessa etapa foi conduzido um estudo para determinar um meio otimizado para a produção de biomassa máxima pela recombinante Pichia pastoris com cultivo em frascos agitados usando 2,31% (p/v) de glicerol como fonte de carbono. A otimização foi realizada por metodologia de superfície de resposta (RSM). Em experimentos preliminares, realizados seguindo um planejamento Plackett-Burman, o conteúdo de glicerol (Gli) e tempo de crescimento (t) foram selecionados como os fatores mais importantes na produção de biomassa. Assim, os ensaios subsequentes foram realizados para a otimização da produção de biomassa, seguindo um delineamento composto central rotacionado. ; In this study, was initially used to study the response surface methodology (RSM) has been adopted frequently in optimization with many applications in biotechnology. A review ...

Aiming to meet the environmental needs of the world economy and protect the environment from the exacerbated consumption of fossils, the seventh Goal defends clean and affordable energy. In search of evaluation strategies and public policies for the sustainable market, providing circularity in production processes, the circular has become an economic model. Bioenergy comes to a growing world energy demand and energy resources for energy consumption comes in the global energy matrix in the mitigation of complementary forests of greenhouse gases, in food security, in the greenhouse and in the economy. More specifically, it carried out a review of eco-efficiency recommendations and the international energy framework for bioenergy (PFE) for a bioenergy from a circular economy perspective; evaluated the echo of PFEs through a multi-criteria analysis, adjusting to a global concentration and competitiveness of their exports. The methodologies used were bibliometrics and content analysis; a multi-criteria analysis (Promethee); market concentration indicators; differential and structural analysis, and; revealed comparative advantages. The main results that are efficient and the bioenergy economics studies are recent, the most important being the most environmentally friendly PFEs and the pellets are the most recent. In the late 20th century PFE mergers, as indicators were projected, as final concentrated and competitive mergers. From the 21st century onwards, deconcentration trends occurred and after 2010 of production, exports and FE production had a competitive market. As a consumption, differential and consumption model, which is in front of the PFE carbonization goals, if he is the consumer. In this way, through the comparative advantages revealed, countries with a forestry vocation have specialized in the production of PFE. It is concluded that PFE represents an adequate, safe and circular energy option, providing a functional and sustainable market structure. ; Coordenação de Aperfeiçoamento de Pessoal de Nível ...

This paper seeks to analyze biomass participation in the context of a global discussion involving the need to address the two key issues of the 21st century: energy security and climate change. The idea was to try to discuss the growth of energy demand and the representativeness of renewable sources to reduce dependence on fossil fuel sources both in the domestic supply of energy (OIEE) and in theinternal energy supply (OIE). It is based on a more general approach that involves the discussion on sustainability and the transformation and use of biomass in the world and after an analysis involving changes in the Brazilian electricity sector (SEB) since 2004. The assumption that guided this research highlighted the importance of energy for the economic development of any country or nation, as well as biomass and other renewable energies, in the context of the need to deal with climate change. In Brazil, the discussions about the field of energy in general and of electricity, specifically, go through the effort to organize the electrical system, seeking the possibility of contracting new sources of energy, especially renewable ones, such as wind, biomass, the small Hydroelectric Power Plants (SHP), solar. This contracting is carried out in specific contracting environments and conditions for pricing according to the tariff modification criterion, in the case of the Regulated Contracting Environment (ACR), as well as taking into account the energy sold in the Free Contracting Environment (ACL).The importance of renewable energies in SEB is also highlighted by a brief approach on the importance of the Alternative Energy Sources Incentive Program (PROINFA) in the process of market creation for renewable sources. By means of the methodology used, it is concluded that the biomass follows an expansion trajectory, especially sugarcane bagasse, where its relative importance was verified in the process of contracting this source in the ACR. Therefore, it is estimated that biomass will continue to be important in the national ...

Young plants of Coffea arabica grafted over C. canephora were submitted to six watering cycles (WC) during 35 days. Each WC was accomplished until net photosynthesis (PN) close to zero or leaf water potential (Ψ) close to -2.0 MPa in Acauã (AC), Mundo- Novo (MN), and Obatã (OB) cultivars. After 2 WC (about 10 days) gs dropped from 0.15 to 0.01 mol m-2 s-1 in all cultivars changing the pattern of leaf gas exchange in subsequent WC. From 3 to 6 WC the cultivars showed high oscillations of water use efficiency or substomatal CO2 concentration (Ci) besides negative PN at the end of WC. After 3 WC, gs increased faster than PN after watering and Ci increased indicating some damage in photosynthetic machinery. It happened strongly in OB, which showed progressive reduction of PN after 3 WC and the lowest values of Ψ (-2.0 MPa) at the end of 6 WC. The survivorships for cultivars were 80% till 3 WC and 70% after 6 WC. The gas exchange pattern alteration could indicate the potential hardening of AC, MN and OB cultivars. After field plantation of hardened and control (without perivous hardening) Mundo-Novo and Obatã cultivars, with 180-days-old, it was observed significant (p<0.05) greater accumulation of leaf, stem and root biomass in hardened in control plants. Stem diameter, height and the number of leaf and branch were also higher (p<0.05) in previous hardened individuals. Greater differences in crown structure and biomass between control and hardened plants were observed mainly after the first period of low water availability (210 days under field conditions). The higher leaf number and leaf area in more branched crowns could carbon assimilation and grain production. For practical proposes, 3 WC before growing under field conditions are sufficient for changing consistently the leaf gas exchange pattern in 3 cultivars studied, keeping photosynthetic machinery free of damage and high survivorship. Previous hardening proportioned less interrupted vegetative development after transplantation under field conditions in ...

Dissertação de Mestrado em Engenharia do Ambiente apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra. Pelo seu carácter renovável, abundância, baixo custo e risco de incêndio, a biomassa florestal é vista pelos especialistas como uma das alternativas mais promissoras para um futuro energético sustentável, através do aproveitamento energético. De entre as tecnologias que proporcionam um aproveitamento energético eficiente e de baixo impacte ambiental encontra-se a gaseificação, que consiste num processo de conversão da matéria orgânica por oxidação parcial num gás combustível, constituído fundamentalmente por hidrogénio (H2) e monóxido de carbono (CO), e em percentagens menores, por dióxido de carbono (CO2), água (H2O), metano (CH4), hidrocarbonetos (C2+) e azoto (N2). Entre outros fatores a produção de gás é afetada pela temperatura, pressão, teor de oxigénio no reator e o tipo e humidade do combustível. Neste trabalho é apresentado um resumo bibliográfico dos sistemas de gaseificação, descrevendo a sua evolução histórica, os tipos de gaseificadores, as etapas do processo de conversão, os poluentes e as formas de limpeza do gás. É feita a caracterização físico-química da biomassa florestal (pinheiro bravo e eucalipto), tendo em conta a sua composição; é avaliado o processo de decomposição térmica e são estimados os parâmetros cinéticos da reação de decomposição, admitindo uma reação de decomposição de 1ª ordem, sendo obtido para a madeira de eucalipto uma energia de ativação de 198 kJ/mol e um fator pré-exponencial de 2,87x1014 s-1. O potencial energético da biomassa foi medido para diferentes graus de humidade, tendo-se obtido para a madeira de eucalipto (seca) um PCS de 19,43 kJ/kg e para madeira de pinho bravo (seca) um PCS de 20,25 kJ/kg. The abundance, renewable classification, low price and high risk of fire makes forest biomass as one of the most promising options for a sustainable energy future. Among the technologies that allows high energy efficient and low environmental impact using forest biomass appears gasification. Biomass gasification allows the conversion of organic matter into syngas by partial oxidation. The composition is mainly hydrogen (H2) and carbon monoxide (CO), and in lower percentage carbon dioxide (CO2), water (H2O), methane (CH4), hydrocarbons (C2+) and nitrogen (N2). Syngas production is dependent on the temperature, pressure, oxygen content in the reactor and fuel type and moisture. This paper presents an overview of the gasification systems, describes their historical development, types of gasifiers, the conversion process and the gas cleaning systems. Physical and chemical characterization of forest biomass (pine and eucalyptus) is described and the thermal analysis is carried out to estimate the kinetic parameters. The thermal decomposition of eucalyptus described by a 1st order reaction provides an activation energy of 198 kJ/mol and a pre-exponential constant of 2.87x1014 s-1. The high heat value (HHV) of eucalyptus and pine were measured as a function of the moisture. Under dry basis a HHV of 19.43 kJ/kg for eucalyptus and a HHV of 20.25 kJ/kg for pine is obtained.

The present work had as objective to use guava residues (seeds) as biomass for the production of bio-oil through conventional pyrolysis. The biomass presented a moisture content of 3.49 ± 0.03 %, high carbon content (67.04 %), nitrogen (3.96 %), oxygen (22.86 %), hydrogen (6.18 %), protein content (11.81 ± 0.36 %), fiber (11.78 ± 0.45 %), calorific power (24.69 MJ kg -1), ash content (0.76 ± 0.02 %), oil (11.78 ± 0.45 %), cellulose (48.71 %), hemicellulose (11.52 %) and lignin (10.12 %). The thermogravimetric curve of the sample amounts to 90 % of mass loss at 450 °C. The biomass was used in two reactors (quarzto and inox) for the production of bio-oil. Preliminary, the experiments in a quartz reactor evaluated the conditions: temperature (500 to 700 °C), sample mass (5 and 11 g) and pyrolysis time (5 and 10 min) with flow 1mL min-1. The best condition in the quartz reactor was 500 °C, 11 g of seed with the collection time of 5 min and 17.1 % of bio-oil yield. The following experiments were carried out in the steel reactor with constants pyrolysis temperature and flow, 500 ºC and 1mL min-1, respectively. Also, the following variables: sample mass (10 and 20 g), granulometry (seed entire and grain) and salts (K2HPO4 and K3PO4). The best condition in the stainless steel reactor was 20 g of sample, ground seed and without addition of salt, obtaining 23.94 % of bio-oil yield. Since the bio-oil was obtained, it was submitted to liquid-liquid extractions in a 250 mL separating funnel using dichloromethane (DCM) (60 mL) to separate the organic phase (bio-oil) and aqueous phase. For the improvement with model molecule (phenol), diisobutylene was used as reagent and sulfuric acid, Amberlyst (A-15) and sulfated zirconia as catalysts. The conditions for the enhancement were temperature (120 to 180 ° C), molar ratio (1: 1 to 1: 5) and percentage of catalyst (1 to 5% w / w), where the best product conversion was gotten with 150 °C, 1: 3 ratio and 3 % Amberlyst (A-15) yielding 99.8 % product conversion. From the last ...

We present a system of alometric biomass equations for aboveground compartments for Pinus pinea L. that allows biomass estimation with information from conventional forest inventories. We harvested 40 trees located in south of Portugal and separated and weighed all the aboveground components: needles, stem bark, branches and stem. The equations were simultaneously fitted using seemingly unrelated regression. This method allows the compatibility of the partial allometric equations with the equation for total biomass aboveground that corresponds to the sum of those 4 equations. The models were better for stem (R2adj.=0.85) and bark (R2adj.=0.83) and worst for branches (R2adj.=0.79) and needles(R2adj.=0.71). Crown biomass was always high compared with aboveground biomass, independently on stand characteristics. However it may be exacerbated by artificial pruning that is carried out to increase crown expansion for pine nut production. The different stand management circumstances from where trees harvested were selected may explain the worst fitting for crown components.

Dissertação para obtenção do grau de Mestre em Engenharia Mecânica Este trabalho tem como intuito analisar a viabilidade de uma mini central a biomassa com forno rotativo. O estudo centrou-se na importância da biomassa, nas características do forno, na sua aplicação numa mini central a biomassa e na averiguação da viabilidade destas centrais. A biomassa destaca-se como uma fonte de energia despachável, neutra em carbono e renovável, quando utilizada de forma sustentável, tornando-se uma alternativa promissora para substituir as energias fósseis no setor eletroprodutor. Analisaram-se as mini centrais com forno rotativo ao nível do funcionamento, equipamentos, otimização e dificuldades operacionais. Avaliou-se a combustão no forno rotativo, revelando-se a necessidade de uma câmara de pós-combustão para garantir a oxidação total dos gases e conformidade com regulamentos ambientais. Demonstrou-se ser preferível utilizar o estagiamento de ar devido à redução simultânea de emissões de uma combustão incompleta e de NOx. Relativamente a aspetos particulares destas instalações, mostrou-se a importância de controlar o tempo de residência e assegurar uma mistura adequada dos sólidos, para permitir uma combustão completa e uniforme, e a necessidade de observar regularmente o estado do tijolo refratário, e a presença de fissuras e desalinhamento no forno, para garantir o seu bom funcionamento. A avaliação da viabilidade abrangeu os pontos de vista técnico, ambiental, económico e social. No ponto de vista técnico o forno destaca-se na versatilidade de queima de combustível, mas tem uma baixa eficiência térmica. Sob a perspetiva ambiental e social não se verificaram diferenças para outras tecnologias de combustão, mas evidenciou-se ser vantajoso, de uma forma geral, utilizar a biomassa. Economicamente, o forno tem um custo de investimento relativamente baixo, mas um custo de manutenção elevado. A baixa eficiência térmica e os custos de manutenção podem justificar a baixa utilização do forno rotativo em centrais termoelétricas a biomassa. This work aims to conduct a feasibility analysis of a small scale biomass power plant with a rotary kiln. The study focused on the value of biomass, the characteristics of the kiln, its application in a small scale biomass plant, and the assessment of the feasibility of such facilities. Biomass stands out as a dispatchable, carbon-neutral, and renewable energy source, when utilized sustainably, emerging as a promising alternative to replace fossil fuels in the power generation sector. Small scale power plants with rotary kilns were analyzed, concerning their functioning, equipment, optimization, and operational challenges. Combustion in the kiln was also evaluated, revealing the need for a post-combustion chamber to ensure the complete oxidation of gases and compliance with environmental regulations. It proved preferable to implement air staging due to the simultaneous reduction of emissions from incomplete combustion and NOx. Regarding specific aspects of these facilities, the importance of monitoring residence time and ensuring an adequate mixture of solids was emphasized to enable complete and uniform combustion, and regular observation of the state of the refractory brick, along with the detection of cracks and misalignment in the kiln, was underscored to ensure its proper functioning. The feasibility assessment encompassed technical, environmental, economic, and social perspectives. From a technical standpoint, the kiln stands out in its versatility of fuel burning but has a low thermal efficiency. Regarding environmental and social aspects, no significant differences were observed compared to other combustion technologies, but it was generally evident that utilizing biomass is advantageous. Economically, the kiln has a relatively low initial investment cost, but high maintenance expenses. The combination of low thermal efficiency and maintenance costs may account for the limited utilization of rotary kilns in biomass power plants. N/A

Macaúba (Acrocomia aculeata (Jacq.) Lodd. ex Mart.) is a palm tree with an oleaginous fruit which endocarp may have potential as an alternative aggregate to produce bio-concretes.This paper proposes a study of the characteristics of the endocarp of macaúba, to evaluate its potential and behavior as a coarse aggregate in bio-concretes. The endocarp used for the study was provided by the Engineering Department of the Federal University of Lavras (UFLA), located in Lavras, MG, Brazil. The endocarps were characterized as to its chemical composition, anatomical characteristics, physical properties and durability in alkaline conditions The chemical compatibility between the endocarp and the cement matrix was evaluated by semi-adiabatic calorimetry analysis with macauba endocarp treated and untreated with Ca(OH)2 and hot water in a proportion of 10% in relation to the cement mass. Bio-concretes were developed using Portland cement (CP- V ARI), with substitutions in mass and volume of 25, 50 and 100% of coarse aggregate by macauba endocarp. The bio-concretes were mechanically characterized by axial compression and tensile tests by diametrical compression. The results showed that the endocarp has a bulk density of 1.23 g/cm3 and an absorption capacity of 9%. Chemical analysis showed a high lignin content (39.60%) and low extractive content (3.10%). The durability of the endocarp was more compromised in the presence of alkaline NaOH solution after 30 and 60 days, with a decrease in mechanical strength and modification of the chemical composition of the material. The hot water treatment was more efficient in removing extractives from the endocarp and improving the chemical compatibility with the matrix. The addition of 25% of the volume of coarse aggregate by macauba endocarp provided a bio- concrete with compressive strength of approximately 30 MPa, within the strength range required for application as structural concrete in civil construction. ; Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) ; A ...