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1.
Waste Manag Res ; 41(9): 1486-1495, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37293743

RESUMO

The Brazilian Northeast region has considerable agricultural potential for corn and cashew nuts production. Residues from these cultures can be densified into pellets and used as heat generators in industries and homes. In this study, corn straw pellets (CSP) and cashew nut shells pellets (CNSP) were handmade, together with a variation using glycerol as a binder (CSGP and CNSGP). All pellets were subjected to chemical, thermal and exhaust gas analyses of their combustion. All analyses were based on two different scenarios: (i) the use of CSP and CSGP for energy supply in residential use and (ii) the use of CNSP and CNSGP for energy supply in industrial use. All pellets were subjected to chemical, thermal and exhaust gas analyses of their combustion. Chemical analysis involved the study of various fuel properties, comprehending moisture content (%U), bulk density (kg m-3), volatile materials (%V), ash content (%C) and fixed carbon (%FC), and all evaluated pellets met two or more international trading standards. The combustion process analyses in the residential scenario showed higher average temperatures and lower carbon monoxide (CO) and nitrogen oxide (NOx) concentrations obtained during CSP combustion than those of CSGP, and in the industrial scenario showed average similar temperatures and lower CO and NOx concentrations obtained during CNSP combustion than those of CNSGP. Ours results demonstrate the great potential of corn straw and cashew nut shells as crops to be integrated into the biomass supply chain for energy generation and agro-ecological development.


Assuntos
Anacardium , Zea mays , Zea mays/química , Nozes/química , Temperatura , Óxidos de Nitrogênio/análise , Óxido Nítrico , Biomassa
2.
Environ Toxicol Pharmacol ; 83: 103583, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33434645

RESUMO

Air pollution has association with chronic obstructive pulmonary disease (COPD) and reduced life expectancy. This study investigated the deleterious effects caused by tobacco smoke and diesel exhaust particles (DEP) from vehicles operating under EURO 3 and EURO 5 standards. Experiments were carried out on C57BL/6 mice divided into six groups: control group, group exposed to cigarette smoke (CS), two groups exposed to DEP (AAE3 and AAE5), and two groups exposed to tobacco smoke and vehicle DEP (CSE3 and CSE5). Results showed that, when compared to AA, groups AAE3 and AAE5 showed changes in respiratory mechanics, and that DEP originating from EURO 5 diesel vehicles was less harmful when compared to DEP originating from EURO 3 diesel vehicles. Analyses of groups CSE3 and CSE5 revealed increased inspiratory capacity and decreased tissue elastance, when compared to their respective controls, suggesting an exacerbation of changes in respiratory system mechanics compatible with COPD development.


Assuntos
Poluentes Atmosféricos/toxicidade , Pulmão/efeitos dos fármacos , Fumaça/efeitos adversos , Emissões de Veículos/toxicidade , Animais , Enfisema/patologia , Enfisema/fisiopatologia , Pulmão/patologia , Pulmão/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Veículos Automotores , Nicotiana , Produtos do Tabaco
3.
Eng. sanit. ambient ; 25(3): 521-530, maio-jun. 2020. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1133793

RESUMO

RESUMO A intensificação das atividades industriais e o aumento das emissões veiculares têm contribuído significantemente para o aumento da poluição atmosférica nos centros urbanos. Neste trabalho, avaliou-se a qualidade do ar na área do distrito industrial de Maracanaú, no estado do Ceará, importante área industrial da Região Nordeste do Brasil. As amostragens foram realizadas durante o período de novembro de 2015 a abril de 2016, totalizando 30 coletas com duração de 24 h cada. Realizaram-se coletas para poluentes, como o material particulado total (PTS) e inalável (MP10), NO2, SO2, O3 e metais pesados (Sb, Cd, Pb, Cu, Fe, Mn, Ni e Zn) associados ao PTS e ao MP10. O O3 foi determinado por absorção no ultravioleta (254 nm), e estimaram-se as concentrações dos metais por espectroscopia de absorção atômica. Os valores médios observados para os poluentes foram de: 51,3 µg/m3 de PTS; 46,1 µg/m3 de MP10; 8,9 µg/m3 de SO2; 8,3 µg/m3 de NO2; 38,5 µg/m3 para O3 em 8 horas e 48,4 µg/m3 para O3 em 1 hora. Para os metais, o Fe (14,9 µg/m3) foi o mais abundante em ambos os particulados. Todos os parâmetros encontram-se em conformidade com os valores estabelecidos pela legislação brasileira, e somente o MP10 apresentou em 16,7% das amostras concentrações acima (média de 74,5 µg/m3) do recomendado pela Organização Mundial da Saúde. Em geral, a qualidade do ar na área industrial em estudo pode ser considerada boa, segundo os valores de índice de qualidade do ar (IQAr) recomendado pela agência de proteção ambiental americana.


ABSTRACT The intensification of industrial activities and the increase in vehicular emissions have contributed significantly to the increase in atmospheric pollution in urban centers. In this context, the present study aimed to monitor the air quality in the area of Maracanaú Industrial District, in the state of Ceará, an important industrial area in northeastern region of Brazil. Samples were collected during 24 h from November 2015 to April 2016 for pollutants such as total suspended (TSP) and inhalable particle materials (PM10), NO2, SO2, O3 and heavy metals (Sb, Cd, Pb, Cu, Fe, Mn, Ni, and Zn) associated with TSP and PM10. Ozone (O3) was determined by ultraviolet absorption (254 nm) and the concentration of heavy metals were estimated by atomic absorption spectroscopy. The mean values observed for the pollutant concentrations were: 51.3 μg/m3 for TSP; 46.1 μg/m3 for PM10; 8.9 μg/m3 for SO2; 8.3 μg/m3 for NO2; 38.5 μg/m3 for O3 in 8 hours and 48.4 μg/m3 for O3 in 1 hour. Among metals, Fe (14.9 µg/m3) was the most abundant species in both particulates. All the parameters analyzed are in accordance with the values established by the Brazilian legislation and only PM10 are above the recommended by the World Health Organization in 16.7 % of the samples (mean 74.5 μg/m3). In general, the air quality in the industrial area under study can be considered good, according to the estimates of the air quality index (AQI) recommended by the US Environmental Protection Agency.

4.
Environ Sci Pollut Res Int ; 27(9): 9568-9581, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31919820

RESUMO

Currently, to reduce the use of nonrenewable energy sources in energy matrices, some industries have already incorporated biomass as a source of energy for their processes. Additionally, filters are used in an attempt to retain the particulate matter present in exhaust gases. In this work, the emission gases of a cashew nut shell (CNS) combustion reactor and the deleterious effects on the respiratory system of mice exposed to gaseous fraction present in CNS emissions (GF-CNS) are analyzed. The system for CNS combustion is composed of a cylindrical stainless steel burner, and exhaust gases generated by CNS combustion were directed through a chimney to a system containing two glass fiber filters to retain all the PM present in the CNS exhaust and, posteriorly, were directed to a mice exposure chamber. The results show changes in the variables of respiratory system mechanics (G, H, CST, IC, and PV loop area) in oxidative stress (SOD, CAT, and NO2-), as well as in the histopathological analysis and lung morphometry (alveolar collapse, PMN cells, mean alveolar diameter, and BCI). Through our results, it has been demonstrated that even with the use of filters by industries for particulate material retention, special attention should still be given to the gaseous fraction that is released into the environment.


Assuntos
Poluentes Atmosféricos/análise , Anacardium , Lesão Pulmonar , Animais , Biomassa , Gases/análise , Camundongos , Nozes/química , Material Particulado/análise , Emissões de Veículos/análise
5.
Eng. sanit. ambient ; 23(5): 1013-1025, set.-out. 2018. tab, graf
Artigo em Português | LILACS | ID: biblio-975137

RESUMO

RESUMO No Brasil e no mundo, o setor dos transportes de passageiros e cargas tem contribuído decisivamente para o aumento das emissões de poluentes atmosféricos, com os consequentes problemas para o meio ambiente e para a saúde humana. Assim, muitos estudos têm recorrido a metodologias e/ou ferramentas específicas para modelar e simular poluentes atmosféricos. A frota de veículos no Ceará teve um crescimento de 169% nos últimos 10 anos, mas ainda se desconhece o volume de poluentes emitidos pela frota circulante da Região Metropolitana de Fortaleza (RMF). Nesse contexto, foram estimadas as emissões veiculares de escapamento para a RMF no ano de 2010. A quantificação das emissões de monóxido de carbono (CO), hidrocarbonetos não metano (NMHC), óxidos de nitrogênio (NOx), material particulado (MP) e aldeídos (RCHO) foi realizada através da metodologia bottom-up. De modo geral, as motocicletas apresentaram emissões significativas de poluentes, sobretudo de CO, NOx e MP, devido à grande quantidade de veículos na região. Os veículos ciclo Otto representam mais de 90% das emissões totais de CO, NMHC e RCHO, enquanto os veículos ciclo Diesel emitem mais de 85% das emissões totais de NOx e MP.


ABSTRACT In Brazil and worldwide, the passenger and cargo transportation sectors have decisively been responsible for the increased emissions of air pollutants, which cause serious damages for the environment and human health, as well. Thus, many studies have been carried out to model and simulate pollutant emissions through methodologies and/or specific tools. The vehicle fleet in the state of Ceará has increased by 169% over the last 10 years and, until now, the amount of pollutants released from circulating fleet of the Fortaleza Metropolitan Region (FMR) is unknown. In this context, vehicular exhaust emissions for the FMR were estimated for the year 2010. Emission estimates of carbon monoxide (CO), non-methane hydrocarbons (NMHC), nitrogen oxides (NOx), particulate matter (PM), and aldehydes (RCHO) were performed through the bottom-up methodology. In general, it was observed that motorcycles emitted high amounts of pollutants, mainly CO, NOx and MP, due to the large number of vehicles in the region. Otto cycle vehicles accounted for more than 90% of CO, NMHC and RCHO total emissions, while Diesel cycle vehicles emitted more than 85% of NOx and PM total emissions.

6.
Environ Toxicol Pharmacol ; 56: 1-9, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28858710

RESUMO

Air pollution is a topic discussed all over the world and the search for alternatives to reduce it is of great interest to many researchers. The use of alternative energy sources and biofuels seems to be the environmentally safer solution. In this work, the deleterious effects on the respiratory system of mice exposed to PM4.0 or TSP, present in exhaust gases from the combustion of CNS were investigated, through data from respiratory system mechanics, oxidative stress, histopathology and morphometry of the parenchyma pulmonary. The results show changes in all variables of respiratory system mechanics, in oxidative stress, the histopathological analysis and lung morphometry. The results provide experimental support for epidemiological observations of association between effects on the respiratory system and exposure to PM4.0 or TSP from CNS combustion exhaust gases, even at acute exposure. It can serve as a basis for regulation or adjustment of environmental laws that control the emissions of these gases.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Pulmão/patologia , Sistema Respiratório/efeitos dos fármacos , Fumaça/efeitos adversos , Anacardium , Animais , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Estresse Oxidativo , Tamanho da Partícula , Material Particulado/toxicidade
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