Este trabalho avaliou a sustentabilidade do sistema de gestão de resíduos sólidos urbanos (RSU) do município de Volta Redonda, no estado do Rio de Janeiro, utilizando indicadores de sustentabilidade. Aplicando a técnica Delphi, os indicadores foram priorizados quanto ao grau de importância, resultando em 17 indicadores distribuídos nas dimensões: ambiental, política, tecnológica, financeira, do conhecimento e social. Os indicadores foram avaliados no município em estudo. Observou-se que a falta de um Plano Municipal de Gestão Integrada de Resíduos Sólidos (PMGIRS) aliado a outros fatores como o reduzido número de lixeiras públicas e uma coleta seletiva pouco efetiva contribuem para um cenário menos sustentável. A falta de investimentos em capacitação de agentes de limpeza pública atrelada à falta de pontos de entrega voluntária de resíduos segregados e a não execução do PMGIRS resultaram em uma gestão menos sustentável dos RSU no município.

This work aimed to identify and quantify greenhouse gases (GHG) emissions of a steel factory, considering the importance of these data in the context of large global GHG emissions. As a result, Scope 1 emissions were identified as the highest in the industry, representing more than 89% of total emissions in CO2eq. This scenario is mainly identified a result of the Brazilian energy matrix configuration, which contributes to reduce Scope 2 emissions. The used methodology (GHG Protocol v. 2018.1.4) proved to be appropriate for calculating emissions within a broader report (annual amount). However, in order to develop an indicator for the organi-zation, with monthly detailed data, it was necessary to adapt the tool, which is the differential of this work.

The risks of scarcity have forced several countries to change their water resources management. In Brazil, the Paraíba do Sul River has a great importance as it supplies water for many cities of the Southeast region. Thus, the management of water and wastewater systems demands a more sustainable and efficient scenario. The study's objective was to evaluate, through sustainability indicators, the urban water management system in Volta Redonda (Rio de Janeiro state, Brazil). The selection of sustainability indicators was done through Delphi technique: a group of eight specialists selected the indicators used to evaluate sustainability, its dimension and level of importance. The six criteria for the classification of indicators according to the dimensions of sustainability were: (1) Environmental / Ecological, (2) Economic, (3) Social / Cultural, (4) Technological (5) Ethical and (6) Political / Institutional. Most of the indicators were considered "very important" or just "important". Regarding the dimension of sustainability, 93% of indicators contemplated more than three dimensions. However, 13 indicators contemplated all the six dimensions as they were multidimensional indicators, analyzed according to the municipal data. The chosen method for the indicator's selection was considered quite satisfactory, since they were able to generate a set of key indicators to show the current municipal water and wastewater scenario. The city has shown satisfactory conditions regarding fresh water supply index. However, some indicators pointed a not sustainable system due to the low wastewater treatment index, precarious state of the river's life and divergences between the basin plan and the municipal director plan.

Biodiesel has been presented worldwide as a viable alternative to petroleum-based fuels. In 2018, the main raw materials in this Brazilian sector was soybean (70.52%) and beef tallow (13.4%). The Brazilian mandatory biodiesel-diesel blend is currently 10% (B10), but B20 is estimated for 2030. Additionally, the National Program for the Production and Use of Biodiesel (PNPB) intends to promote the diversification of raw materials in the energy matrix, where the beef tallow - a residue of the beef production - has been increasing importance. Brazil presents as the global largest commercial beef producer and exporter. Then, the use of beef tallow would allow the expansion of biodiesel production without fuel x food competition and provide a nobler use than disposal for it. In this sense, this article analyzes, through a review, the potential of beef tallow for biodiesel production in Brazil. This raw material has price, quantity and quality for generating a biodiesel in the specifications required by regulatory agencies. Therefore, beef tallow is a potential raw material for the expansion of the biodiesel sector in Brazil and this experience can be useful for other countries.

Hydrogen has been presented as a promising vector, influencing the actual energy system. In Brazil, the industrial use of hydrogen is consolidated, however national projects for energetic hydrogen are not continuous. So, this work shows the possibilities for a Hydrogen Economy (HE) transition in Brazil, analyzing the competitiveness' drivers of the hydrogen productive chain and, also, identifying strengths and weaknesses, challenges and recommendations, in order to increase its competitiveness. The employed methodology was to apply a qualitative model to analyze the competitiveness' drivers of the chain through literature review and interview with key stakeholders in Brazil. Besides the availability and diversification of inputs able to produce hydrogen in Brazil, the results show the need of investments in research, development and innovation. On top of this, it is necessary the diffusion of new technologies and to create an infrastructure of production, storage, transportation and distribution of hydrogen. In order to have a national chain of suppliers of components is necessary advances for standardization and certification of industries, and partnerships with developed technology countries. Finally, it is worth pointing out the need of continuous public policies able to restore programs and projects for hydrogen development.

A gestao inadequada de residuos e rejeitos no Brasil e uma realidade condicionada a maioria dos Municipios. Atraves de uma Acao Civil Publica instaurada pelo Ministerio Publico Federal e pelo Ministerio Publico Estadual – RJ, celebrou-se um termo de ajustamento de conduta com a Prefeitura de Volta Redonda, propondo a remediacao e o encerramento da area de disposicao de residuos. Identificou nao conformidades das acoes da Administracao Publica municipal na gestao da area. Atraves de analise comparativa entre os padroes de qualidade ambiental e as concentracoes de parâmetros do lixiviado, constatou-se que alguns constituintes toxicos encontrados no lixiviado nao sao regulamentados em lei e normas, levando a propositura de atualizacao dos parâmetros legais de lancamento de efluentes.

The city of Volta Redonda, located in the state of Rio de Janeiro, has a controlled landfill of municipal solid waste (MSW) which was partially recovered in 2008. This disposal site has no data on the amount of waste volume landfilled. An Unmanned Aerial Vehicle (UAV) was used to capture images of the study area and through Geographic Information Systems (GIS) the biogas generation was determined. By overlaying the georeferenced images the contour lines were determined which enabled the creation of the 3D Digital Terrain Model (DTM) of the area with a resolution of 0.296349 m / pix. The DTM provided the determination of the volume of waste landfilled (535.755,79 m3) and the real surface area (36.770,96 m2) of the controlled landfill. These parameters allowed obtainment the maximum flow rate of methane generation of 16.539,82 m3 for 2007. The Brazilian model used to determination biogas generation in waste sector achieve a maximum flow rate of methane generation of 126.599,4 m3 for the year 2007. A significant difference between biogas generation in the two models was observed mainly due to the amount of waste determined in both models.

Inadequate management of waste in Brazil is a reality conditioned to the majority of municipalities. Through a Public Civil Action established by the Federal Public Ministry and the State Public Ministry - RJ, a behavior adjustment agreement was signed with the city of Volta Redonda, proposing the remediation and closure of the waste disposal area. Non conformities of municipal Public Administration actions were identified in the management of the activity. Through the comparative analysis of the environmental quality standards and the concentrations of leachate parameters, it was found that some toxic constituents found in the leachate are not regulated by law and norms leading to the proposition of updating the legal parameters of effluent release.

There is a worldwide debate about which energies are more efficient and renewable energy systems. This discussion comprises hydrogen and fuel cells as potential emerging technologies. However, information about hydrogen technology remains somehow unknown to a broader public. Currently some technologies supporting hydrogen productive chain are not so competitive and this means a tight bottleneck. Expectation is that this would be the most promising innovation in a new energy system based on renewable sources. This paper reports the large range of existing processes and technological routes for the production of hydrogen in many countries. Thus, this work aims to show the current energy landscape, highlighting the hydrogen and the main characteristics of the technological routes for its production. The overview about the current situation and trends of Hydrogen Economy is presented. The prominent research on hydrogen technology, processes and their main characteristics are addressed as well. The uncertainties surrounding the implementation of hydrogen energy, based on renewable sources, require further studies regarding competitiveness.

Pt–Cu catalysts supported on Al2O3 and Nb2O5 were studied for use in selective CO oxidation. The addition of copper enhanced the activity and selectivity of Pt–Cu/Nb2O5 at lower temperatures when compared to Pt/Nb2O5. On the other hand, copper addition was not beneficial in the case of Al2O3 supported catalysts.

The selective oxidation of CO in the presence of H2 was investigated on Au catalysts promoted with different amounts of Cu. Au catalysts were prepared by the deposition–precipitation method and exhibited a satisfactory activity at low temperature with adequate selectivity. A considerable improvement in CO conversion was achieved when the O2/CO ratio was increased from the value of 0.5–1.0. The addition of Cu to Au/Al2O3 catalysts caused an increase in the selectivity to CO oxidation due to an interaction between Au and Cu on the surface of the catalysts. However, this beneficial effect was limited to an optimal content of Cu. The catalysts were characterized by temperature programmed reduction and DRS UV–vis spectroscopy, indicating the formation of small bimetallic Au–Cu particles. The presence of water vapor in the feed stream played a positive effect in the CO conversion and selectivity while the CO2 presence diminished the CO conversion and selectivity. In the case of a realistic reformate, when both H2O and CO2 are present, the positive effect of H2O was able to compensate the negative effect of CO2 depending on the temperature of reaction.