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1.
Waste Manag Res ; 35(5): 541-550, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28462678

RESUMO

Because the consumption of materials is generally higher than their recovery rate, improving municipal solid waste (MSW) management is fundamental for increasing the efficiency of natural resource use and consumption in urban areas. More broadly, the characteristics of a MSW management system influence the end-of-life (EOL) impacts of goods consumed by households. We aim to indicate the extent to which greenhouse gas emissions from a MSW management system can be reduced by increasing waste paper recycling. We also address the stakeholders' contribution for driving transition towards an improved scenario. Life cycle assessment (LCA) addresses the EOL impacts of the paper industry, driven by the characteristics of MSW management in Florianópolis, Brazil, by varying the level of stakeholders' commitment through different recycling scenarios. The results show that 41% of the climate change impacts from waste paper management could be reduced when increasing the waste paper recycling rates and reducing waste paper landfilling. To achieve such emissions reduction, the industry contribution to the MSW management system would have to increase from 17% in the business-as-usual scenario to 74% in the target scenario. We were able to measure the differences in stakeholders' contribution by modelling the MSW management system processes that are under the industry's responsibility separately from the processes that are under the government's responsibility, based on the Brazilian legal framework. The conclusions indicate that LCA can be used to support policy directions on reducing the impacts of MSW management by increasing resource recovery towards a circular economy.


Assuntos
Resíduos Sólidos , Gerenciamento de Resíduos , Brasil , Mudança Climática , Efeito Estufa , Eliminação de Resíduos
2.
J Environ Manage ; 133: 222-31, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24388925

RESUMO

This study compared the environmental burdens of two broiler chicken production systems in Brazil and two in France. One Brazilian system represents large-scale production in the Center-West region of the country; the other is a small-scale production in the South. One of the French systems represents an extensive broiler chicken production system, known as "Label Rouge"; the other is a standard system. Life-cycle impact assessments were performed using the CML-IA characterization method. The main functional unit adopted was 1 tonne of cooled and packaged chicken, ready for distribution. For the systems and impacts studied, production scale did not affect the environmental impact, but production intensity did. The extensive Label Rouge system had the largest impact among the impact categories studied. This resulted principally from the high feed-conversion ratio of this production system (3.1 kg of feed per kg of live weight) in conjunction with the fact that the feed-production stage contributed most to the overall impact. The contribution of deforestation to the crop-production stage was significant, particularly for climate change, equaling 19% of total emissions of CO2eq per tonne of cooled and packaged chicken, in the system of the Center-West of Brazil. The French systems were also affected, since they import crops from Brazil. The system of southern Brazil had less climate change impact because there is no longer deforestation in southern Brazil for crop production.


Assuntos
Meio Ambiente , Produtos Avícolas , Animais , Brasil , Galinhas , França
3.
J Environ Manage ; 106: 102-9, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22579725

RESUMO

Oysters represent a substantial fraction of the world's overall intensive aquaculture production. In Brazil, oyster aquaculture is still in the deployment phase but has the potential for growth and, likewise other aquaculture products, generate environmental impacts over their life cycle. Special attention should be devoted to the disposal or processing of the oyster shells, whose high calcium carbonate content (80-95%) gives them the potential for use as raw material for several other products. The objective of this study was to conduct a cradle-to-grave Life Cycle Assessment (LCA) of 1 kg of oysters produced in southern Brazil, incorporating the recycling of the oyster shells on the LCA. Two scenarios were considered. The first scenario (termed scenario A) assumed that the oyster shells were deposited in a landfill, whereas the second scenario (scenario B) assumed that the shells were processed to make them available as raw material as a source of CaCO(3). We used Eco-indicator 99 H/A to perform the impact assessment. Scenario A had an overall impact of 93.71 mPt, whereas scenario B had an overall impact of 58.97 mPt. The latter scenario had lower environmental impacts, however they were depended strongly on the distance between the source of the shells (restaurant) and the shell-processing facility. This distance must not be greater than 323 km to yield overall environmental benefits. Moreover, it is hypothesized that the environmental benefits would be even higher than predicted because there is no evidence that all post-consumer shell residues would receive proper waste management, as assumed for scenario A (landfill).


Assuntos
Exoesqueleto , Ostreidae , Reciclagem , Exoesqueleto/química , Animais , Brasil , Carbonato de Cálcio/análise , Meio Ambiente , Ostreidae/anatomia & histologia , Gerenciamento de Resíduos
4.
J Environ Manage ; 91(9): 1831-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20452717

RESUMO

Soybean production and its supply chain are highly dependent on inputs such as land, fertilizer, fuel, machines, pesticides and electricity. The expansion of this crop in Brazil in recent decades has generated concerns about its environmental impacts. To assess these impacts, two representative chains supplying soybeans to Europe were identified: Center West (CW) and Southern (SO) Brazil. Each supply chain was analyzed using Life Cycle Assessment methodology. We considered different levels of use of chemical and organic fertilizers, pesticides and machinery, different distances for transportation of inputs and different yield levels. Because transportation contributed strongly to environmental impacts, a detailed study was performed to identify the routes used to transport soybeans to seaports. Additionally, we considered different levels of land occupation and land transformation to represent the impact of deforestation in the CW region. Environmental impacts were calculated for 1000 kg of soybean up to and including the delivery to Europe at the seaport in Rotterdam, at 13% humidity. Overall results showed that the impacts are greater for CW than for SO for all impact categories studied, including acidification (7.7 and 5.3 kg SO(2) eq., respectively), climate change (959 and 510 kg CO(2) eq.), cumulative energy demand (12,634 and 6,999 MJ) and terrestrial ecotoxicity (4.9 and 3.1 kg 1,4-DCB eq.), except eutrophication and land occupation. The same trend was observed for the crop-production stage. Efforts to reduce chemical fertilizers and diesel consumption can reduce CO(2) emissions. Although deforestation for crop production has decreased in recent years, the contribution of deforestation to climate change and cumulative energy demand remains significant. In the CW scenario deforestation contributed 29% to climate change and 20% to cumulative energy demand. Results also showed that although there are different transportation options in Brazil, the current predominance of road transport causes severe environmental impacts. In CW, road transport contributed 19% to climate change and 24% to cumulative energy demand, while in SO it contributed 12% and 15% to these impacts, respectively. Improvements in the logistics of transportation, giving priority to rail and river transports over road transport, can contribute significantly to reducing greenhouse gas emissions and decreasing energy use. Future studies involving Brazilian soybeans should take into account the region of origin as different levels of environmental impact are predicted.


Assuntos
Agricultura , Meio Ambiente , Poluição Ambiental , Glycine max , Meios de Transporte , Brasil , Mudança Climática , Eutrofização , Medição de Risco
5.
Sci Total Environ ; 726: 138111, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32305774

RESUMO

The search for sustainability has pointed to the need to transition from a linear to a circular model. However, such a transition is not trivial. Modifying production chains with the focus on reducing virgin raw materials consumption, cut emissions, and prevent waste generation implies implementing new processes and services, which can add considerable environmental impacts to the supply chain. This paper analyzes a real case from a production system aligned with circular economy principles. The production system consists of the manufacturing of baseboards made of recycled Expanded Polystyrene (EPS), obtained from an extensive reverse logistics system composed of different recycling processes. The system's potential environmental impacts were assessed by two widely used methodologies, Life Cycle Assessment (LCA) and Emergy Analysis (EMA). For comparison purposes, the analysis was carried out for a fictional linear production system, in which the baseboard would be made of virgin EPS. EMA attributed a lower emergy load to the circular scenario compared to the linear scenario (8.62E+15 seJ to recycled EPS versus 1.26E+16 seJ to virgin EPS). LCA results indicate both scenarios as environmental preferable depending on the impact category under analysis (e.g. circular system has better performance regarding global warming, while the linear scenario demonstrated better results under water consumption). For the circular scenario, EMA identified the main impact drivers, such as transportation and electricity consumption. From LCA perspective impacts are also driven by electricity consumption. However, differently from EMA, logistics were only significant for Land Use impact category whereas Liquefied Petroleum Gas consumption and, landfill air emissions were identified as impact hotspots. These convergences and differences between the findings of LCA and EMA have demonstrated potentially complementation to broaden available information related to systems, enabling decision makers to act effectively in improving the environmental performance of their production processes, especially when implementing circular practices.

6.
Sci Total Environ ; 741: 140273, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887019

RESUMO

The intensification of milk production in Brazil in the past decade has imposed great stress on the environment. Therefore, it is very important to find a balance between economic, social, and environmental objectives. The paper assesses the economic costs by production systems: confined feedlot, semi-confined feedlot, and pasture in the south of the country. The economic assessment was realized on some investment analysis tools and the GHG emissions costs for the different production systems indicated. Our results show that hectare and the total area of rural properties were lower in the confined feedlot system, followed by the semi-confined feedlot system and pasture-based grazing system. However, the reduction of the need for feed inputs in the pasture system resulted in lower feeding costs when compared to the other systems. The hectare analysis suggested that the superior productivity of the semi-confined system conditioned higher emission costs in relation to the other systems. However, considered the total emissions of the systems, the pasture system obtained higher values, justified by the greater need for an area for production. The results showed that the higher the food efficiency of a system, the greater the profitability.

7.
Waste Manag ; 33(1): 175-83, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23122202

RESUMO

The establishment of rules to manage Health Care Waste (HCW) is a challenge for the public sector. Regulatory agencies must ensure the safety of waste management alternatives for two very different profiles of generators: (1) hospitals, which concentrate the production of HCW and (2) small establishments, such as clinics, pharmacies and other sources, that generate dispersed quantities of HCW and are scattered throughout the city. To assist in developing sector regulations for the small generators, we evaluated three management scenarios using decision-making tools. They consisted of a disinfection technique (microwave, autoclave and lime) followed by landfilling, where transportation was also included. The microwave, autoclave and lime techniques were tested at the laboratory to establish the operating parameters to ensure their efficiency in disinfection. Using a life cycle assessment (LCA) and cost analysis, the decision-making tools aimed to determine the technique with the best environmental performance. This consisted of evaluating the eco-efficiency of each scenario. Based on the life cycle assessment, microwaving had the lowest environmental impact (12.64 Pt) followed by autoclaving (48.46 Pt). The cost analyses indicated values of US$0.12 kg(-1) for the waste treated with microwaves, US$1.10 kg(-1) for the waste treated by the autoclave and US$1.53 kg(-1) for the waste treated with lime. The microwave disinfection presented the best eco-efficiency performance among those studied and provided a feasible alternative to subsidize the formulation of the policy for small generators of HCW.


Assuntos
Eliminação de Resíduos de Serviços de Saúde/economia , Compostos de Cálcio/economia , Custos e Análise de Custo , Desinfecção/economia , Micro-Ondas , Óxidos/economia
8.
Eng. sanit. ambient ; 14(1): 39-48, jan.-mar. 2009. ilus, tab
Artigo em Português | LILACS | ID: lil-512045

RESUMO

A quantidade de resíduos sólidos industriais tem aumentado significativamente em decorrência da industrialização, e o seu gerenciamento adequado é necessário para reduzir o impacto ao meio ambiente e aos ecossistemas. Neste trabalho, foram avaliadas a integridade e a retenção de metais pesados em materiais estabilizados por solidificação. Foi adotado o planejamento completamente aleatorizado com um único fator, ou seja, foram comparadas as médias de quatro tratamentos (A, B, C e D) com 0, 40, 50 e 60 por cento respectivamente de contaminantes e três repetições. Cimento Portland comum, bentonita sódica e hidróxido de cálcio foram usados para estabilizar por solidificação o resíduo sólido sintético contendo óxido de Cd2+, Pb2+ e Cu2+. Pode-se concluir que os tratamentos influenciaram no resultado de lixiviação do cádmio, chumbo e cobre. Os tratamentos mostraram que as concentrações do extrato solubilizado e lixiviado aumentam em função da quantidade de cádmio, chumbo e cobre adicionada. O maior valor encontrado foi para o material proveniente do tratamento D, que apresentou lixiviação igual a 32,815 mg.kg-1 para o cádmio e 29,769 mg.kg-1 para o chumbo. Para os ensaios de integridade/durabilidade, constatou-se que o aumento da absorção de água fez com que a resistência à compressão diminuísse. O uso de cimento, de hidróxido de cálcio e de bentonita sódica se mostrou ideal para retenção de metais pesados, evitando a sua lixiviação e a solubilização para o meio ambiente.


As the quantity of hazardous industrial wastes increases significantly owing to rapid industrialization, its appropriate management is required to reduce adverse impacts on humans and ecosystems. This work evaluated the integrity and retention of heavy metals in materials stabilized by solidification. It was adopted a completely randomized design with a single factor, that is, the averages of four treatments were compared (A, B, C and D) with 0, 40, 50 and 60 percent respectively contaminants and three repetitions. Portland cement, bentonita and lime-fly ash binders were used to solidify a synthetic heavy metal sludge containing oxides of Cd2+, Pb2+ e Cu2+. It can be concluded that the treatment influenced the result of leaching of cadmium, lead and copper. The treatments showed that the concentrations of solubilized and leachate extract increase with the amount of cadmium, lead and copper added. The highest price was found in the material from the treatment D, that presented leaching equal to 32.815 mg.kg-1 for cadmium and 29.769 mg.kg-1 for the lead. For the tests of integrity/durability, it was found that increasing the absorption of water has caused resistance to compression decreased. The use of cement, calcium hydroxide and sodium bentonite were ideal for retention of heavy metals, avoiding leaching and solubilization for it's the environment.

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