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‣ Pollutant emissions from modern incinerators

Lima, R.; Bachmann, R.
Fonte: Indersicence Publicador: Indersicence
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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Presently, emissions of dioxins are mainly from incinerators, domestic and industrial coal combustion, and traffic. However, the major public concern and research effort are associated with the emissions of organic micropollutants from waste incinerators. Therefore, this paper attempts to give a brief overview on the more recent research and development for the removal of dioxins and heavy metals from flue gas streams. Special attention is devoted to the origin and control of emissions from incinerators. From the study presented it is possible to conclude that flue gas cleaning systems in modern incinerators are very reliable in removing almost all polluting emissions from flue gas streams, however the fly ash residues generated pose a significant disposal problem. In this way, the fly ash has to be managed carefully as it is enriched with heavy metals and organic micropollutants.

‣ Analysis of the emissions of volatile organic compounds from the compression ignition engine fueled by diesel-biodiesel blend and diesel oil using gas chromatography

FERREIRA, S. L.; SANTOS, A. M. dos; SOUZA, G. R. de; POLITO, W. L.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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This paper describes the procedures of the analysis Of Pollutant gases, as volatile organic compounds (benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene) emitted by engines, using high-resolution gas chromatography (HRGC). In a broad sense, CI engine burning diesel was compared with B10 and a drastic reduction was observed in the emissions of the aromatic compounds by using B10. Especially for benzene, the reduction of concentrations occurs on the level of about 19.5%. Although a concentration value below 1 mu g ml(-1) has been obtained, this reduction is extremely significant since benzene is a carcinogenic compound. (c) 2008 Elsevier Ltd. All rights reserved.

‣ Emissions from the premixed combustion of gasified polyethylene

GONCALVES, Cecilia K.; TENORIO, Jorge A. S.; LEVENDIS, Yiannis A.; CARLSON, Joel B.
Fonte: AMER CHEMICAL SOC Publicador: AMER CHEMICAL SOC
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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An investigation was conducted on pollutants emitted from steady-state, steady-flow gasification and combustion of polyethylene (PE) in a two-stage furnace. The polymer, in pulverized form, was first pyrolyzed at 1000 degrees C, and subsequently, its gaseous pyrolyzates were burned, upon mixing with air at high temperatures (900-1100 degrees C). The motivation for this indirect type of burning PE was to attain nominally premixed combustion of the pyrolyzate gases with air, thereby achieving lower pollutant emissions than those emanating from the direct burning of the solid PE polymer. This work assessed the effluents of the two-stage furnace and examined the effects of the combustion temperature, as well as the polymer feed rate and the associated fuel/air equivalence ratio (0.3 < phi < 1.4). It was found that, whereas the yield of pyrolysis gas decreased with an increasing polymer feed rate, its composition was nearly independent of the feed rate. CO2 emissions peaked at an equivalence ratio near unity, while the CO emissions increased with an increasing equivalence ratio. The total light volatile hydrocarbon and semivolatile polycyclic aromatic hydrocarbon (PAH) emissions of combustion increased with an increasing equivalence ratio. The generated particulates were mostly submicrometer in size. Overall...

‣ Avaliação de fatores intervenientes nas emissões veiculares em corredores de ônibus.; Appraisement of factors affecting vehicular emissions in high-flow bus corridors.

Castro, Carlos Fernando Carvalho de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 02/10/2008 Português
Relevância na Pesquisa
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Esta dissertação investiga a influência de diversos fatores intervenientes nas emissões veiculares em corredores de ônibus de alta capacidade, conhecidos como BRT Bus Rapid Transit. Esses sistemas têm sido adotados em cidades de todo o mundo devido a possibilidade de atender demandas elevadas a custos relativamente baixos quando comparados com alternativas sobre trilhos, com nível de serviço adequado e possibilitando a redução de emissões. Três categorias de variáveis foram consideradas: (i) variáveis que são função do projeto do corredor de ônibus (infraestrutura, especificações tecnológicas e operacionais); (ii) variáveis que são afetadas pela implantação do corredor (impactos na velocidade média dos outros veículos, utilização de rotas alternativas e transferência modal); (iii) variáveis que dependem de políticas públicas (como mudanças do tipo de combustível ou programas de inspeção veicular). As emissões foram estimadas através de dois procedimentos. Preferencialmente utilizou-se o modelo IVE International Vehicle Emissions, que se baseia no ciclo de condução dos veículos (perfil de variação da velocidade segundo a segundo). Em alguns casos, as estimativas utilizaram resultados de medidas de emissões realizadas pelo IPT Instituto de Pesquisas Tecnológicas...

‣ Construção de ciclos de condução para estimativa de emissões veiculares para ônibus urbanos.; Driving cycles construction for urban buses emissions estimation.

Maciel Filho, Francisco Fernando
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 09/10/2013 Português
Relevância na Pesquisa
48.599%
O objetivo principal deste trabalho de pesquisa é desenvolver ciclos de condução para ônibus urbanos a partir de dados de campo, visando sua aplicação em metodologias de estimativa de emissões de poluentes. São apresentadas metodologias para a construção de ciclos de condução, com destaque para o procedimento que utiliza o conceito de VSP (Vehicle Specific Power), variável que apresenta forte correlação com emissões de poluentes. Assim, foram coletados dados da variação da velocidade ao longo do tempo em ônibus que realizam testes de durabilidade, percorrendo diariamente diferentes tipos de vias urbanas em um trajeto pré-determinado. Foram selecionados segmentos do trajeto que, agrupados, podem representar diferentes condições de operação para ônibus urbanos; em seguida, foram propostos ciclos de condução para estes segmentos escolhidos, nos períodos de pico e fora do pico. Foram estimadas as emissões dos principais poluentes para os ciclos de condução desenvolvidos. Os resultados mostram que as características das vias e as condições de tráfego desfavoráveis podem impactar diretamente na distribuição de VSP e, consequentemente, ocasionar emissões mais elevadas de poluentes.; The main objective of this research is to develop driving cycles for urban buses from experimental data...

‣ Comparative study for hardwood and softwood forest biomass: Chemical characterization, combustion phases and gas and particulate matter emissions

Amaral, Simone Simoes; Carvalho Junior, Joao Andrade de; Martins Costa, Maria Angelica; Soares Neto, Turibio Gomes; Dellani, Rafael; Scavacini Leite, Luiz Henrique
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 55-63
Português
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 08/04490-4; Two different types of typical Brazilian forest biomass were burned in the laboratory in order to compare their combustion characteristics and pollutant emissions. Approximately 2 kg of Amazon biomass (hardwood) and 2 kg of Araucaria biomass (softwood) were burned. Gaseous emissions of CO2, CO, and NOx and particulate matter smaller than 2.5 mu m (PM2.5) were evaluated in the flaming and smoldering combustion phases. Temperature, burn rate, modified combustion efficiency, emissions factor, and particle diameter and concentration were studied. A continuous analyzer was used to quantify gas concentrations. A DataRam4 and a Cascade Impactor were used to sample PM2.5. Araucaria biomass (softwood) had a lignin content of 34.9%, higher than the 23.3% of the Amazon biomass (hardwood). CO2 and CO emissions factors seem to be influenced by lignin content. Maximum concentrations of CO2, NOx and PM2.5 were observed in the flaming phase. (C) 2014 Elsevier Ltd. All rights reserved.

‣ Performance and emissions of a gas turbine engine using ox tallow ethyl-ester blended with kerosene

Silva, Ramon E. P.; Lacava, Pedro T.; Carvalho, Joao A.
Fonte: Abcm Brazilian Soc Mechanical Sciences & Engineering Publicador: Abcm Brazilian Soc Mechanical Sciences & Engineering
Tipo: Artigo de Revista Científica Formato: 23-28
Português
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The performance and emissions behavior of a Rover 1S/60 turboshaft engine when operated with several blends of aviation kerosene and ox tallow ethyl-ester are shown in this article. The tests were performed with a compressor shaft coupled to an hydraulic dynamometer where data of power and mass fuel flow were collected to determine the brake specific fuel consumption. A flue gas analyzer was positioned at the exhaust duct to collect oxygen, carbon dioxide, carbon monoxide and nitrous oxides. An increase in the specific fuel consumption was observed due to the lesser lower heating value of the most oxygenated blends. However, reductions of CO, CO2 and NO (x) have been observed and no-significant ill effects have occurred in the turbine operation.

‣ The impact of biofuels for road traffic on air quality : a modelling approach; Modelação do impacto do uso de biocombustíveis nos transportes rodoviários na qualidade do ar

Ribeiro, Isabel Lavrador
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
48.10988%
The selection of the energy source to power the transport sector is one of the main current concerns, not only relative with the energy paradigm but also due to the strong influence of road traffic in urban areas, which highly affects human exposure to air pollutants and human health and quality of life. Due to current important technical limitations of advanced energy sources for transportation purposes, biofuels are seen as an alternative way to power the world’s motor vehicles in a near-future, helping to reduce GHG emissions while at the same time stimulating rural development. Motivated by European strategies, Portugal, has been betting on biofuels to meet the Directive 2009/28/CE goals for road transports using biofuels, especially biodiesel, even though, there is unawareness regarding its impacts on air quality. In this sense, this work intends to clarify this issue by trying to answer the following question: can biodiesel use contribute to a better air quality over Portugal, particularly over urban areas? The first step of this work consisted on the characterization of the national biodiesel supply chain, which allows verifying that the biodiesel chain has problems of sustainability as it depends on raw materials importation...

‣ Global wildland fire emissions from 1960 to 2000

Schultz, Martin G.; Heil, Angelika; Hoelzemann, Judith J.; Spessa, Allan; Thonicke, Kirsten; Goldammer, Johann; Held, Alexander C.; Pereira, J.M.C.; Bolscher, Maarten
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em //2008 Português
Relevância na Pesquisa
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In many regions of the world, fires are an important and highly variable source of air pollutant emissions, and they thus constitute a significant if not dominant factor controlling the interannual variability of the atmospheric composition. This paper describes the 41-year inventory of vegetation fire emissions constructed for the Reanalysis of the Tropospheric chemical composition over the past 40 years project (RETRO), a global modeling study to investigate the trends and variability of tropospheric ozone and other air pollutants over the past decades. It is the first attempt to construct a global emissions data set with monthly time resolution over such a long period. The inventory is based on a literature review, on estimates from different satellite products, and on a numerical model with a semiphysical approach to simulate fire occurrence and fire spread. Burned areas, carbon consumption, and total carbon release are estimated for 13 continental-scale regions, including explicit treatment of some major burning events such as Indonesia in 1997 and 1998. Global carbon emissions from this inventory range from 1410 to 3140 Tg C/a with the minimum and maximum occurring in 1974 and 1992, respectively (mean of 2078 Tg C/a). Emissions of other species are also reported (mean CO of 330 Tg/a...

‣ Penetration of hydrogen technologies: study on the environmental impact of road transport in Portugal

Travassos, Maria Antónia; Sá, A. I. Correia de; Luz, Paulo P. da; Rangel, C. M.
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em 24/09/2008 Português
Relevância na Pesquisa
48.221978%
Road traffic is one of the transportation sectors with faster growth and also one of the most important emitters of greenhouse gases (GHGs). In this work, an analysis of the environmental benefits resulting from the introduction of hydrogen on road transport in Portugal is made. Impact is analyzed mainly looking at the pollutant emissions provided by road transport at the point of use. Emissions associated to road transport have been estimated using the software COPERT (version 4), since it provides a detailed methodology for each specific pollutant related to the vehicle fleet of a region or country, as well as the driving conditions and fuel consumption. Passenger cars, light duty vehicles and public transport buses are the vehicles categories in which the hydrogen technology is foreseen. The hydrogen penetration rates (moderate and high) are extracted from the European Project HYWAYS. Two trends are then considered, which give penetration rates of 40.0 % and 74.5 % in 2050 for the moderate and high scenarios respectively.

‣ Reduction of pollutants emissions on SI engines: accomplishments with efficiency increase

Vianna,J. N. de S.; Reis,A. do V.; Oliveira,A. B. de S.; Fraga,A. G.; Sousa,M. T. de
Fonte: Associação Brasileira de Engenharia e Ciências Mecânicas - ABCM Publicador: Associação Brasileira de Engenharia e Ciências Mecânicas - ABCM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2005 Português
Relevância na Pesquisa
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This paper presents an experimental study aiming to identify the means to minimize the reduction of the overall performance of a gasoline engine when employing the Exhaust-Gas Recirculation (EGR) technique that reduces NOx emissions. The increase of the compression ratio and turbocharging was evaluated as a mean to recover the original performance. The formation of pollutants and the engine performance were verified at full and partial loads. The results show that the combination of exhaust gas recirculation with turbocharger or through an increase of the compression ratio enhance the relation between the engine performance and the emission of NO. However, the turbocharger seemed to be more sensitive to the negative effects of the EGR technology.

‣ Análise do balanço energético e da matriz de emissões de poluentes no Estado do Rio Grande do Norte

Silveira, Tházia Viviane Silva da
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia de Produção; Estratégia; Qualidade; Gestão Ambiental; Gestão da Produção e Operações Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia de Produção; Estratégia; Qualidade; Gestão Ambiental; Gestão da Produção e Operações
Tipo: Dissertação Formato: application/pdf
Português
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This thesis intends to show the level of pollutant emissions in the State of Rio Grande do Norte, generated by the final consumption of energy in the many different sectors of the economy. This information was obtained from the energetic matrix and from the pollutant emissions of the State and the data was taken from the Balanço Energético Estadual and from the Sistema de Informações Energéticas da Olade. The result will permit to identify the energy and most polluting economic sectors in Rio Grande do Norte, contributing to energy planning, giving direction to the public policy development that aim at the change of the energy matrix of the State. Also with the objective of reducing pollutant emissions through rationalization, efficiency and energy substitution, which the main objective is to promote the economic development based on energy consumption of less harmful impact on the environment, contributing to establishment of sustainable development; A dissertação pretende apresentar o nível de emissões em que se encontra o Estado do Rio Grande do Norte, geradas com o consumo final de energéticos nos diversos setores da economia. Esta informação foi obtida a partir da matriz energética e de emissões poluentes do Estado...

‣ Formulação de novos combustíveis base diesel: avaliação de desempenho e emissões; Formulation of new diesel-based fuels: Evaluation of performance and emissions

Fernandes, Manoel Reginaldo
Fonte: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Química; Pesquisa e Desenvolvimento de Tecnologias Regionais Publicador: Universidade Federal do Rio Grande do Norte; BR; UFRN; Programa de Pós-Graduação em Engenharia Química; Pesquisa e Desenvolvimento de Tecnologias Regionais
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
48.10988%
The industry, over the years, has been working to improve the efficiency of diesel engines. More recently, it was observed the need to reduce pollutant emissions to conform to the stringent environmental regulations. This has attached a great interest to develop researches in order to replace the petroleum-based fuels by several types of less polluting fuels, such as blends of diesel oil with vegetable oil esters and diesel fuel with vegetable oils and alcohol, emulsions, and also microemulsions. The main objective of this work was the development of microemulsion systems using nonionic surfactants that belong to the Nonylphenols ethoxylated group and Lauric ethoxylated alcohol group, ethanol/diesel blends, and diesel/biodiesel blends for use in diesel engines. First, in order to select the microemulsion systems, ternary phase diagrams of the used blends were obtained. The systems were composed by: nonionic surfactants, water as polar phase, and diesel fuel or diesel/biodiesel blends as apolar phase. The microemulsion systems and blends, which represent the studied fuels, were characterized by density, viscosity, cetane number and flash point. It was also evaluated the effect of temperature in the stability of microemulsion systems...

‣ Bangladesh : Reducing Emissions from Baby-Taxis in Dhaka

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Português
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The program, "Reducing Emissions from Baby-Taxis in Dhaka," included the education of commercial two-stroke engine three-wheel vehicle drivers and owners through mechanics training, a baby-taxi "auto clinic," meetings, dissemination of information, and informational meetings with auto mechanics and gasoline station owners who come in contact with vehicle drivers on a regular basis. The activity also sought to restructure the market for lubricants through both private voluntary action and government policy reform. To this end, the following activities were undertaken: Quantifying the impact of the use of excess inferior quality lubricant on emissions from baby-taxis; Training of mechanics servicing baby-taxis; Holding an auto clinic to demonstrate to the drivers the merit of changing their behavioral pattern with respect to the use of lube oil and vehicle maintenance; Consensus-building within the downstream petroleum sector on a ban on the; sale of straight mineral oil at gasoline stations; Other awareness-raising and dissemination activities to educate the drivers and the public on what affects vehicle emissions.

‣ The Artemis European Tools for Estimating the Transport Pollutant Emissions

ANDRÉ Michel; KELLER Mario; SJÖDIN Åke; GADRAT Marie; MC CRAE Ian; DILARA Panagiota
Fonte: Environmental Protection Agency Publicador: Environmental Protection Agency
Tipo: Contributions to Conferences Formato: Printed
Português
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International engagements as well as impact studies require accurate and agreed methods for assessing pollutant emissions from the road transport. This ARTEMIS project - with 40 European research laboratories and a budget of about 9 M¿ was initiated for the setting-up and improvement of the European inventorying tools for application at different spatial and temporal scales and which should enable objectives comparisons and evaluations. These tools rely on experimental works and integrate most of the European related knowledge. They concern all transports modes in Europe, their pollutant emissions and fuel consumption as well as their characteristics of use. The ARTEMIS project resulted in many important scientific results and in a unique state of the art on the topic in Europe. We recapitulate the main lines of the project and its results: emission measurements, principles of the modelling, street-scale approach based on the definition of traffic situations, and the resulting tools. The tools application requires detailed and reliable data describing the traffic (vehicle fleets and activity, driving conditions, etc.). We highlight this aspect through the ARTEMIS application in Sweden, first country to implement the tools for emissions reporting...

‣ Impact on vehicle speeds and pollutant emissions of a fully automated section speed control scheme on the Naples urban motorway

PUNZO VINCENZO; CASCETTA Ennio; BONNEL Pierre
Fonte: ITS world congress Publicador: ITS world congress
Tipo: Contributions to Conferences Formato: DVD
Português
Relevância na Pesquisa
48.221978%
Section speed enforcement systems are becoming established as cost-effective measures to reduce the incidence of speeding and thus improve road safety. It is also widely acknowledged that speed levels affect pollutant emissions. Therefore, significant co-benefits in environment and road safety are expected from the application of such systems. Yet few studies have investigated the environmental effects of speed limit reduction and even fewer those of tight speed limit enforcement. In this study an empirical analysis is carried out to investigate the impact of a new 80km/h speed limit and tight enforcement on an urban motorway in Italy. First a detailed analysis of individual-vehicle section speeds (i.e. section travel times) is performed. The study focuses on seven motorway sections and three reference periods, namely weekday peak hours, free-flow hours and the entire week. This allows the effect of road geometry and traffic conditions to be evaluated as well. Secondly, thorough calculation of pollutant emissions and fuel consumption is carried out. As it is based on individual vehicle speeds, the effect of changes in speed variance among drivers is also captured. This turned out to be relevant to the application. Basically, study outcomes suggest that the strategy can be a straightforward and effective policy to put eco-driving principles into practice...

‣ Effect of Biodiesel Fuels on Pollutant Emissions from EURO 3 LD Diesel Vehicles (1)

MARTINI GIORGIO; ASTORGA LLORENS Covadonga; FARFALETTI CASALI ARIANNA; BOTTA Marzio; REY GARROTE Maria; MANFREDI URBANO; KRASENBRINK ALOIS; LARSEN BO; DE SANTI GIOVANNI
Fonte: OPOCE Publicador: OPOCE
Tipo: EUR - Scientific and Technical Research Reports Formato: Printed
Português
Relevância na Pesquisa
48.239053%
Transport is a key factor in modern economies. However, the EU transport system is currently not sustainable, and in many respects moving away from sustainability rather than towards it. The European Environment Agency highlights in particular the sector's growing CO2 emissions that threaten the EU meeting its target under the Kyoto protocol. Transport also represents a key challenge to sustainability in terms of depletion of resources and European competitiveness, safety and security concerns, especially due to the monolithic reliance on a single energy source. As stated in the Commission’s November 2000 Green Paper on security of supply, in 1998 energy consumption in the transport sector was to blame for 28 % of emissions of CO2, the leading greenhouse gas. In particular, road transport alone accounts for 84 % of the CO2 emissions attributable to transport. Furthermore, in terms of security of energy supply, there is growing concern for the current situation of transport sector that depends on crude oil for more than 99%. In the above mentioned Green Paper the European Commission has also identified the measures to tackle these problems and, among them, one the most important is the promotion of alternative fuels; the ambitious target that has been proposed by the Commission is to replace 20% of conventional fuels with substitute fuels by 2020. According to the Commission White Paper “European transport policy for 2010: time to decide” the most promising forms are biofuels in the short and medium term...

‣ Reducing Black Carbon Emissions from Diesel Vehicles : Impacts, Control Strategies, and Cost-Benefit Analysis

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
Português
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A 2013 scientific assessment of black carbon emissions and impacts found that black carbon is second to carbon dioxide in terms of its climate forcing. High concentrations of black carbon in the atmosphere can change precipitation patterns and reduce the amount of radiation that reaches the Earth's surface, which affects local agriculture. Acute and chronic exposures to particulate matter are associated with a range of diseases, including chronic bronchitis and asthma, as well as premature deaths from cardiopulmonary disease, lung cancer, and acute lower respiratory infections. The transportation sector accounted for approximately 19 percent of global black carbon emissions in the year 2000. This report aims to inform efforts to control black carbon emissions from diesel-based transportation in developing countries. It presents a summary of emissions control approaches from developed countries, while recognizing that developing countries face a number of on-the-ground implementation challenges. This study applies a new cost-benefit analysis methodology to four simulated diesel black carbon emissions control projects - diesel retrofit in Istanbul...

‣ Estimating Traffic Emissions Using Demographic and Socio-Economic Variables in 18 Chilean Urban Areas

González, Patricio; Osses Alvarado, Mauricio; Urrutia, Cristian M.; Corvalán, Roberto M.
Fonte: Population & Environment Publicador: Population & Environment
Tipo: Artículo de revista
Português
Relevância na Pesquisa
47.759497%
A macro-scale methodology for vehicle emissions estimation is described. The methodology is based on both correlations between activity level and PM, CO, THC and NO x vehicle emissions and relationships between demographic and socio-economic variables and transportation activity level. First, pollutant emissions were correlated with transportation activity, expressed as vehicle-km/year, using existing data collected from mobile sources emission inventories in nine urban cities of Chile. Second, demographic and socio-economic variables were pre-selected from those that could intuitively be correlated with vehicle activity level and considering the data availability. Using the individual R 2 correlation coefficient as variable selection criterion, population, the number of vehicles, fuel consumption, gross domestic product, average family incomes and road kilometers were finally chosen. A different set of explicative variables was considered for different vehicle categories, based on the selection criterion above mentioned. Then, correlation functions between these variables and transport activity were obtained by non-linear Gauss–Newton least square method. This methodology was applied to eighteen provinces of the country obtaining total annual emission for mobile sources...

‣ Environmental impact assessment of the penetration of hydrogen technologies in Portugal's road transport

Travassos, Maria Antónia; Sá, A. I. Correia de; Luz, Paulo P. da; Rangel, C. M.
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Publicado em 01/04/2009 Português
Relevância na Pesquisa
48.221978%
Road traffic is one of the transportation sectors with faster growth and also one of the most important emitters of greenhouse gases (GHGs). In this work, an analysis of the environmental benefits resulting from the introduction of hydrogen on road transport in Portugal is made. Impact is analyzed mainly looking at the pollutant emissions provided by road transport at the point of use. Emissions associated to road transport have been estimated using the software COPERT (version 4), since it provides a detailed methodology for each specific pollutant related to the vehicle fleet of a region or country, as well as the driving conditions and fuel consumption. Passenger cars, light duty vehicles and public transport buses are the vehicles categories in which the hydrogen technology is foreseen. The hydrogen penetration rates (moderate and high) are extracted from the European Project HYWAYS. Two trends are then considered, which give penetration rates of 40.0 % and 74.5 % in 2050 for the moderate and high scenarios respectively.