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Resumo: O aproveitamento energético do biogás de aterros sanitários é uma alternativa sustentável para a disposição final de gases residuais. A estimativa teórica da produção desse biogás torna-se uma ferramenta muito útil para a avaliação de viabilidade e dimensionamento de sistemas de coleta de gás. Os modelos de geração de biogás de aterro mais utilizados atualmente são os baseados em equações de decaimento de primeira ordem. Os modelos LandGEM e IPCC foram utilizados neste trabalho para a estimativa da geração de gases no aterro municipal de Guarapuava (PR, Brasil), onde os principais parâmetros foram escolhidos com base nos dados frequentemente aplicados para cada modelo: valores default sugeridos para as condições locais específicas, para a aplicação do software LandGEM; e cálculo do potencial de geração de metano (L0) a partir da análise gravimétrica dos resíduos, para a aplicação da equação sugerida pelo IPCC. Estimou-se uma produção total de biogás de 44.466.711 Nm3.ano-1 aplicando LandGEM e 60.080.906 Nm3.ano-1 aplicando IPCC, onde os picos de produção foram observados nos anos de 2021 e 2020, respectivamente. A escolha do modelo mais adequado dependerá dos dados disponíveis e, para maior aproximação de resultados reais, os parâmetros adotados devem ser analisados com cautela, considerando as diferentes condições climáticas e operacionais de cada caso. ; Abstract: The energetic use of landfill biogas is a sustainable alternative for the final disposal of waste gases. The theoretical estimation of the production of this biogas becomes a very useful tool for evaluating the feasibility and design of gas collection systems sizing. The most widely used landfill biogas generation models are those based on first-order-decay equations. LandGEM and IPCC models were used in this work to estimate the generation of gases in the municipal landfill of Guarapuava (PR), and the main parameters were chosen based on the frequently applied data for each model: default values suggested for the specific local ...

Resumo: Este trabalho teve por objetivo avaliar a influência da utilização de diferentes inóculos de dejeto suíno em diferentes proporções na determinação do potencial de geração de biogás a partir da fração orgânica de resíduos sólidos urbanos (RSU). Utilizou-se dejeto suíno como inóculo do RSU nas proporções 1 gsv resíduo:1 gsv inóculo e 3gsv resíduo:1 gsv inóculo. Todos os biodigestores foram incubados à temperatura constante (32ºC) por 50 dias. Observou-se que a geração média de biogás (volume gerado) foi altamente dependente da proporção resíduo:inóculo utilizada. A eficiência da mistura resíduo:inóculo na proporção 3:1 foi superior à proporção 1:1 em termos de volume de biogás gerado. ; Abstract: The present work focused on evaluating the influence in using swine manure inoculum in different proportions in order to determinate the biogas generation from organic fraction of municipal solid waste (MSW). We employed swine manure as inoculum of the MSW at 1 gvswaste:1gvsinoculum and 3 gvswaste:1gvsinoculum ratios. All biodigestors were incubated at constant temperature (32ºC) for 50 days. We could observe that the biogas generation (in volume) was highly dependent of the waste:inoculum ratio used. The efficiency of the blend 3:1 was upper compared to 1:1, taking into account the volume of biogas.

Neste trabalho, é feita a análise da eficiência de produção de uma serraria de pequeno porte, localizada no estado de São Paulo, utilizando como ferramentas a "análise de fluxo de massa" e "análise de fluxo de energia". O objetivo foi avaliar a linha de produção e comparar as ferramentas utilizadas em função dos resultados obtidos e aplicabilidade. Concluiu-se que o "lay out" de disposição dos maquinários deve ser alterado e deve-se utilizar um melhor planejamento do gabarito de corte para que o sistema se torne viável em função da baixa eficiência com grande porcentagem de perda e uso inadequado dos equipamentos e matéria-prima. As ferramentas forneceram resultados similares e por causa da aplicabilidade, propõe-se a utilização da "análise de fluxo de massa" para avaliação de comportamento produtivo de serrarias. ; This is the analysis of the efficiency of production of one small sawmill, located in São Paulo, using as an instrument of study the "Mass and Energy Flow", available in the production line. It was concluded that the disposal of the machines should be modified, and that the inclusion of a process of planning of cut design is necessary so that the system becomes viable, since the current configuration presents low income with great percentage of loss and inadequate use of equipment and raw material. Concerning the tools, similar results were found and because of its ease of utilization the "mass and flow" is recommended to the sawmill pattern evaluation.

Resumo: O presente estudo avaliou a influência de parâmetros físico-químicos na previsão de geração de biogás a partir da co-digestão da fração orgânica de resíduos sólidos urbanos (FORSU) inoculados com dejeto suíno nas proporções 1 gsv resíduo:1 gsv inóculo e 3gsv resíduo:1 gsv inóculo. Todos os tratamentos foram conduzidos em modo batelada e temperatura constante (32ºC) por 50 dias. Os parâmetros monitorados foram umidade, sólidos totais voláteis (STV) e pH e permitiram avaliar a influência de cada um no processo e sua ação conjunta na condução da biodigestão e consequente geração de biogás. A análise dos parâmetros fisicoquímicos indicou condições favoráveis ao processo de biodigestão. ; Abstract: The present work focused on evaluating the influence of physical-chemical parameters in the forecast of biogas generation from codigestion of the organic fraction of municipal solid waste (OFMSW) codigested with swine manure at 1 gvs waste:1 gvs inoculum and 3gvs waste:1 gvs inoculum ratios. All treatments evaluated were carried out in batch mode and constant temperature (32ºC) for 50 days. Moisture content, volatile solids and pH parameters have been evaluated and allowed to determinate the influence of each one in the process of biodigestion and its influence in biogas generation. The physical-chemical analysis pointed out suitable conditions to biodigestion process. Keywords: Animal manure. Biogas. Codigestion.

Resumo: O presente estudo teve como objetivo avaliar a estrutura de correlação do volume de biogás gerado com as variáveis físico-químicas umidade, pH, alcalinidade, demanda química de oxigênio (DQO) e sólidos totais voláteis (STV), mediante uma análise de componentes principais (ACP). As repetições de cada tratamento, tanto para o inóculo quanto para o substrato, foram submetidas à análise de correlação de Pearson para se determinar se poderiam ser tratadas como réplicas. Para tanto, foram utilizadas 92 unidades amostrais (número de medições diárias referentes à produção de biogás). A produção de biogás dos dois tratamentos (inóculo e substrato) foi avaliada durante 91 dias e entre os tratamentos mediante uma análise de variância (ANOVA). Os tratamentos foram aninhados dentro do tempo, constituindo uma ANOVA com delineamento hierarquizado, com 5% de significância. Os resultados mostraram que a geração de biogás estava mais relacionada com o pH, seguido dos STV, umidade e DQO. A soma da ACP 1 e 2 explicou 98% dos dados de produção de biogás. ; Abstract: This study aimed to evaluate the correlation structure of the biogas volume generated with the physical and chemical variables moisture, pH, alkalinity, chemical oxygen demand (COD) and total volatile solids (STV), through a principal component analysis (PCA). The replicates of each treatment, for both the inoculum and for the substrate were subjected to Pearson correlation analysis to determine if they could be treated as replicas. To this end, we used 92 sampling units (number of daily measurements on the production of biogas). The biogas production of the two treatments (inoculum and substrate) was evaluated for 91 days and between treatments using an analysis of variance (ANOVA). The treatments were nested within time, constituting an ANOVA with hierarchical design, with 5% significance. The results showed that the generation of biogas was more related to the pH, followed by STV, moisture and COD. The sum of the ACP 1 and 2 explained 98% of the biogas ...

Electrochemical devices may potentially solve several issues in various sectors such as production of energy (a combination of thermal and electrical energy), storage (supercapacitors and batteries), and production of fuels from wastes. In the meantime, these technologies have an important role in the commitment of the European Union to transform transport and energy systems as part of a low carbon economy following the Strategic Energy Technologies Plan (SET-Plan). In this scenario, the electrochemical devices offer significant opportunities in increasing efficiency, flexibility and integration due to their specific and intrinsically properties. At the present, there is a significant gap between electrochemical technologies operating at low temperatures (from room temperature to 200 °C) and high temperatures (from 700 °C to 1000 °C). These two groups of technologies are sensibly different one to each other. The relevant characteristics are the high costs of materials for low temperature technologies and high cost for the manufacture and maintenance for high temperature technologies. Another difference concerns with the large sensibility to the poisoning for the low temperatures technologies and the poor flexibility in terms of operation for the high temperatures technologies. These are only few examples of what breakthrough is required. Therefore, the key aspect in this roadmap is the development of new materials. The CNR-ITAE has a long and proven experience in electrochemical devices having contributed to the penetration of these technologies into Europe since the early 1980's. In this seminary will be reported the most recent achievements at CNR-ITAE concerning the low and high temperatures electrochemical cells, including, solid oxide fuel cells, solid oxide electrolyser, solid oxide batteries, polymer electrolyte based fuel cells and electrolyser, polymer membrane based supercapacitors and will be suggested novel approaches in order to mitigate the most common problems affecting these technologies.

Detailed geomorphological and geo-archaeological surveys were carried out in this study at the Greek archaeological site of Selinunte to reconstruct the landscape evolution that occurred before and during the anthropization of the site and to verify the possible correlations between geo-environmental changes and human events that characterized almost four centuries of the history of the city. By using a multidisciplinary approach and different survey techniques, this study testified the role played by climate, geomorphological setting and georesources in conditioning the development of the city and the close relationship sometimes observed between the historical events and natural processes. This included the controversial and never discovered hydraulic work of Empedocles who, according to textual sources, in 444 BC, resolved a public health problem linked to the presence of marshy areas.

Challenges faced by science and environmental educators in respect to the distinctions and interrelationships between these fields have been many over the past few decades. While some scholars note contradicting epistemologies and purposes in their critique of the nature of an environmental (science) education, this paper considers another perspective: through participatory methods it examines how environmental learning may form a unique and qualitatively different context for science education. The paper also highlights a collaborative inquiry into the practices of environmental learning as it is enacted in formal school curriculums in British Columbia, Canada. Our efforts involved critical document analysis of frameworks and resources from around the world. Focus groups and interviews conducted over a period of 16 months informed a collaborative writing process that included teachers, academics and government officials. The framework produced offers a conceptual view for environmental learning in all settings (including science) while providing several principles of teaching and learning to guide educators in designing activities for varied learning contexts. The framework provides a number of perspectives around which environmentally-focused lessons may be developed and demonstrates that environmental education should included scientific understandings but be broadened to include other forms of knowledge including aesthetic appreciation, social responsibility and the development of an environmental ethic.