No description available.

Yes / This study empirically investigates the impact of energy related public environmental concerns on the pay gap within polluting companies. It uses the extreme environmental event of the PM2.5 surge at the end of 2011, which led to an upsurge in energy related public environmental concerns in China, as a quasi-natural experiment. According to our findings, energy related public environmental concerns lead to a significant increase in the executive–employee pay gap of polluting companies compared to that of non-polluting companies, owing to a significant increase in executive compensation and no significant change in employee income. The effect of energy related public environmental concerns on increasing the pay gap within polluting companies is more significant in samples with high agency costs, poor information transparency, less analyst follow-up, and fewer institutional investors' shareholding. Furthermore, as energy related public environmental concerns exacerbate the polluting firms' internal pay gap, their total factor productivity and investment efficiency fall significantly. In summary, energy related public environmental concerns not only widen the wage gap within polluting enterprises but also worsen their operational and investment efficiency, which has important policy implications for emerging market economies seeking to balance environmental protection and economic development. / The authors wew funded by NSFC number (71903199), Fujian Pro vincial Federation of Social Sciences (FJ2023BF045), Guangdong Phi losophy and Social Sciences Project (GD23XYJ08), the Innovation and Talent Base for Digital Technology and Finance (B21038), and "the Fundamental Research Funds for the Central Universities", Zhongnan Univeristy of Economics and Law (2722023EJ002).

京都大学 / 新制・課程博士 / 博士(地球環境学) / 甲第25464号 / 地環博第250号 / 新制||地環||50(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)教授 藤原 拓, 教授 越後 信哉, 教授 梶井 克純, 教授 上田 佳代 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DGAM

運用科學知識在當代環境管制政策幾乎已屬常態。然而，科學卻不一定能有效解決環境污染問題。本研究探討雲林六輕石化廠區的揮發性有機物（VOCs）空氣污染問題，發現運作二十多年的六輕，其排放之VOCs數值，至今尚未釐清，但企業仍不斷擴廠，引發當地健康風險問題；同時，國光石化的環評中，PM2.5（細懸浮微粒）引發重大政治爭議，民間提出對抗性科學論述影響決策方向，後續，更促成相關管制法規通過。 在上述管制科學爭議中，本文採用新政治科學社會學所提供的制度、網絡與權力，與環境決策知識建構的途徑觀點，探討雲林石化廠區所排放的揮發性有機物（VOCs）、懸浮微粒（PM2.5）相關之管制科學爭議。運用次級資料分析法、田野調查以及深入訪談法，嘗試分析強調科學循證作為基礎的管制政策，何以仍落入管制失靈的窘境？本文探討兩個個案，其不同調的科學數字如何依循管制制度生產、傳遞及運用？其中，VOCs排放數字如何被各個政治行動者賦予政治性意涵，進而延宕政府管制的能力？甚而導致府際間嚴重衝突？而PM2.5的對抗性科學論述是如何被生產、傳遞乃至公共化？相關之政策網絡如何有效地將PM2.5的管制政策推入政治議程中，成為正式法規的一環？ 本研究發現，在VOCs個案中，基於污染物的特性、石化廠區的龐大營運複雜度、以及企業為管制資訊之主要來源等因素，使VOCs排放具有相當大的科學不確定性。不過，現行制度將這些科學不確定性切割成一場又一場對於企業資訊的審查，對於掌握確切污染狀況極其有限。在PM2.5個案中，在幾個重大政策窗事件出現之前，民間社會已有一定的知識建構基礎。而重大政策窗事件如六輕工安大火、國光石化興建以及2011年總統選舉等，促成不同社會網絡連結，協助、生產出對抗性論述，並結合公眾媒體的廣泛傳播特性，將相關科技風險知識公共化，終使得PM2.5管制法案成為正式規範之一。 / Scientific knowledge has been commonly employed for making environmental regulatory policies. This thesis aims at analyzing the contamination problems resulted from Volatile Organic Compounds (VOCs) released by the Six Naphtha Cracking Complex; it is discovered that the emission of VOCs remains a mystery after two decades of operation. However, the industrial expansion plan continues and has done a severe environmental and health destruction to the local community. Meanwhile, PM2.5, Fine Particulate Matters also triggered political controversies in the Environmental Impact Assessment process of Kuokuang Petrochemical Plant, the Eighth Naphtha Cracking Project(8th naphtha). The civil society has raised the opposing argument on the PM2.5 matter in terms of health impact, thereby influencing the direction of policy making and passing the regulations. In light of the controversies of regulatory science, this thesis adopts the perspective of New Political sociology of Science (NPSS), which substantiates the approach of institution, network and power, and other aspects of knowledge construction to analyze the emission of VOCs and PM2.5 in the petrochemical field. Moreover, secondary data, field research, and in-depth interviews are utilized to analyze these regulatory predicaments. It is discovered in the cases of VOCs, the scientific uncertainty is composed of the characteristics of VOCs, the complexity of petrochemical plant’s operations and the main regulatory information is generated by industries. Nevertheless, the regulatory institution just divided the scientific uncertainty into the tremendous conferences which peer-reviewed the information from industries. Furthermore, this regulatory institution hinders the true conditions of pollution from being known. In the meantime, in terms of PM2.5, the general public has had a solid knowledge pertaining to the critical national matters, such as several fire disasters of 6th naphtha, the policy of 8th naphtha, and the presidential election in 2011. Moreover, these policy windows promote the connection of social network and assistance, and accordingly generate the opposing discourse. The technology risk-related knowledge has also been conveyed by the mass media, thus ultimately enacting the PM2.5.

Health is closely related to air pollution, with increasing evidence showing the consequences of longand short-term exposure to, in particular, fine particulate matter (PM2.5). In 2008, the European Union adopted a directive (directive 2008/50/EC) to improve air quality and to regulate a number of air pollutants, including PM2.5, in the member states. This directive has recently been assessed by a socalled “fitness check”. The aim of this thesis is to analyse how air quality regarding fine particulate matter has developed in Sweden between 2000 and 2018 and to examine possible future scenarios for stricter requirements in renewed EU legislation, based on the outcomes of the “fitness check”. Data are analysed from monitoring stations throughout Sweden with a focus on the last ten years up to 2018. Average urban exposure levels are estimated to compare them with the average exposure index (AEI) defined in the directive and source sectorsfor PM2.5 are identified to determine the potential for measures to reduce concentrations. The results show that Sweden is not challenged by the current EU legislation, neither exceeding the current annual limit value of 25 µg/m3 nor requiring a reduction of the urban exposure levels. However, Sweden will need to take further initiatives if requirements are tightened up, for example if a daily ceiling of 25 µg/m3 is implemented or the annual limit decreased to 10 µg/m3 , both values based on WHO’s latest recommendations. Rural and urban concentrations show an exponentially decreasing trend from southern to northern Sweden. It is concluded that PM2.5 is dominated by long-distance transportation, but with significant local contributions in urban areas. Overall, concentrations reduced during the period studied, which is mainly due to a reduction in international emissions, occasionally combined with individual local measures. PM2.5 concentrations are, however, above natural background levels, which makes it worthwhile to decrease them further, with local action considered to be of particular importance from a health perspective. / Luftkvalitet är en viktig faktor inom hälsa, eftersom ett stort antal negativa effekter på kroppen har fastställts vid exponering av ökade halter partiklar (PM, eng. ”particulate matter”), bland annat, i luft. Både kort- och långtidsexponering av fina partiklar (PM2.5) har dokumenterade hälsofarliga konsekvenser, därför fastställde den Europeiska unionen under 2008 ett direktiv (direktiv 2008/50/EC) för att förbättra luftkvaliteten och reglera ett antal luftföroreningar, bland annat PM2.5-koncentrationerna i medlemsländerna. För att undersöka implementeringen av direktivet utfördes nyligen en så kallad ”fitness check”. Detta arbete ska analysera hur luftkvalitet i samband med fina partiklar har utvecklats i Sverige under perioden 2000 till 2018. Utöver det undersöks möjliga framtidsscenarier för skärpta krav i ett reviderat EU-direktiv vilka är baserade på slutsatserna från denna ”fitness check”. Data från mätstationer i hela Sverige används med fokus på de sista tio åren fram tills 2018. Genomsnittliga urbana exponeringshalter är uppskattade för att jämföra dessa med exponeringsindexet (AEI, eng. ”average exposure index”) som är definierat i direktivet. Källområden för PM2.5 är identifierade för att uppskatta behovet av potentiella åtgärder för att reducera koncentrationen av fina partiklar. Resultaten visar att Sverige når målsättningen i den befintliga EU-lagstiftningen eftersom varken årsmedelvärdet av 25 µg/m3 eller taket för exponeringsindexet överskrids vid mätstationerna. Om kraven skulle skärpas, till exempel vid implementeringen av ett dygnsgränsvärde av 25 µg/m3 eller om det årliga gränsvärdet skulle sänkas till 10 µg/m3 (i enlighet med WHO:s senaste rekommendationer), kommer det krävas ytterligare åtgärder. Den regionala och urbana koncentrationen uppvisar en exponentiellt avtagande trend från södra till norra Sverige. Slutsatsen kan dras att PM2.5 är dominerad av långdistanstransporter, dock med synliga lokala tillskott i de urbana områdena. Sammanfattningsvis har koncentrationerna reducerats under den observerade perioden, vilket framförallt kan antas vara baserat på en reducering av internationella emissioner, i vissa fall kombinerat med lokala åtgärder. PM2.5 koncentrationerna är fortfarande högre än den naturliga förekomsten, därför är det relevant ur ett hälsoperspektiv att även reducera dem i framtiden, framförallt på lokal nivå.

Les particules fines (PM2.5) suscitent de plus en plus l’intérêt des pouvoirs publics en raison de leurs effets néfastes sur la qualité de l’air et la santé humaine. La mise en place des politiques de réductions efficaces des émissions requière une connaissance détaillée des contributions des principales sources aux concentrations ambiantes en PM. Ainsi, cette thèse a pour objectifs de caractériser la composition chimique des PM2.5, et de quantifier leurs sources d’émissions à Marseille. Pour se faire, une campagne de mesure d’un an (2011-2012) a été conduite sur le site de fond urbain de « Cinq avenues ». La spéciation chimique complète des filtres collectés a été réalisée, et 3 modèles-récepteurs ont été utilisés: CMB (Chemical Mass Balance), PMF (Positive Matrix Factorization), et ME-2 (Multilinear Engine). Bien que basés sur des concepts sensiblement différents, l’exercice d’intercomparaison des sorties de ces modèles a montré globalement un bon accord pour l’estimation des contributions de la combustion de biomasse (entre 23 et 33% en moyenne annuelle) et du trafic véhiculaire (14-26%). En revanche, des différences significatives sont observées pour la source industrielle (1-18%) et le sulfate d’ammonium (12-30%). Cette étude a mis en évidence une contribution importante de la matière organique (OM) qui représente en moyenne 42% des PM2.5. Quant à la quantification des sources, l’un des résultats marquants est la mise en évidence de deux types d’aérosols de combustion de biomasse, dont l’un provient très probablement du brûlage à l’air libre de déchets verts. Ce dernier peut même être considéré comme un contributeur majeur des PM2.5 à l’automne et en début d’hiver. / Fine particulate matter (PM2.5) has received considerable attention due to its impact on human health and air quality. Therefore, effective plans for human health protection require a detailed knowledge of the most relevant PM emission sources and their contributions to the ambient PM levels. Thus, this thesis aims to characterize the chemical composition of PM2.5 collected in Marseille area, and quantify the impacts of the main emission sources. To meet these objectives, a one-year monitoring campaign was conducted at the urban background site of “Cinq avenues” during the period of 2011-2012. A detailed chemical characterization of the collected PM2.5 filters was performed, and 3 receptor models were applied to this database: CMB (Chemical Mass Balance), PMF (Positive Matrix Factorization), and ME-2 (Multilinear Engine). Although based on significantly different concepts, the intercomparison exercise of the output data of the used models has generally showed a good agreement in estimating the source contributions of biomass burning (representing between 23 and 33% on annual average) and vehicular traffic (between 14 and 26%). In contrast, significant differences were observed for the industrial (1-18%) and ammonium sulfate (12-30%) sources. This study highlighted the significant contribution of organic matter (OM), which represents 42% of the PM2.5 mass, on average. Regarding the source apportionment results, one of the most striking findings is the identification of two types of biomass burning aerosol, one of which probably comes from open burning of green waste. The latter can even be considered a major contributor to the PM2.5 mass during fall and early winter

Health impact assessments for fine particulate matter (PM2.5) often rely on simulated concentrations generated from air quality models. However, at the global level, these models often run at coarse resolutions, resulting in underestimates of peak concentrations in populated areas. This study aims to quantitatively examine the influence of model resolution on the estimates of mortality attributable to PM2.5 and its species in the USA. We use GEOS-Chem, a global 3-D model of atmospheric composition, to simulate the 2008 annual average concentrations of PM2.5 and its six species over North America. The model was run at a fine resolution of 0.5 × 0.66° and a coarse resolution of 2 × 2.5°, and mortality was calculated using output at the two resolutions. Using the fine-modeled concentrations, we estimate that 142,000 PM2.5-related deaths occurred in the USA in 2008, and the coarse resolution produces a national mortality estimate that is 8 % lower than the fine-model estimate. Our spatial analysis of mortality shows that coarse resolutions tend to substantially underestimate mortality in large urban centers. We also re-grid the fine-modeled concentrations to several coarser resolutions and repeat mortality calculation at these resolutions. We found that model resolution tends to have the greatest influence on mortality estimates associated with primary species and the least impact on dust-related mortality. Our findings provide evidence of possible biases in quantitative PM2.5 health impact assessments in applications of global atmospheric models at coarse spatial resolutions.

This study is focused on the identification of the sources and processes affecting levels and composition of PM10 and PM2.5 from air quality monitoring networks in Eastern Spain. This is a multidisciplinary study. Time series of TSP and PM10 recorded from 1996 to 2000 are interpreted to assess the role of local, regional and distant sources in PM levels in this region. To this is end, the influence of the meteorology on PM levels recorded at nineteen rural, urban and industrial monitoring stations is studied by means of synoptic charts, back-trajectories and local meteorological variables. The impact of African dust transport on PM levels is investigated by means of simulations in the SKIRON forecast system and by TOMS satellite observations. Moreover, a chemical characterisation of PM10, PM2.5 and TSP size segregated fractions and a daily PM10 and PM2.5 source apportionment by two receptor modelling techniques are performed. For this purpose, 24-hour samples of PM10 were collected for 16, 12 and 5 months at rural, urban and industrial sites, respectively. PM2.5 was sampled at the urban site simultaneously with PM10. The results showed that day-to-day variations in PM levels are highly influenced by the meteorology. From March to October, PM levels at rural, urban and industrial sites vary as a function of the concatenation of Atlantic air mass advections (Atlantic episodes with low PM levels) and regional circulations (Regional events with high PM and O3 levels) which induce the PM transport from urban/industrial to rural sites and the ageing of polluted air masses in the Western Mediterranean. From November to February low PM levels are recorded at rural sites, and variations in PM levels at urban/industrial sites are governed by the successive occurrence of Atlantic episodes and Local urban/industrial pollution events (with high PM, NOx and CO levels). The African dust events mainly occur from January to October and induce very high PM levels in all sites. As a result of the frequency and intensity of the Regional episodes, PM levels at rural sites undergo a seasonal evolution with a summer maximum. The difference between PM levels at urban and rural sites presents an autumn-winter maximum owing to the occurrence of intensive Local urban pollution events. The meteorological context in which the aforementioned episodes occur is discussed, with special emphasis on the synoptic scenarios giving rise to the African dust outbreaks in the different seasons. Levels of PM components at the different study sites were compared. The seasonal evolution and the grain size distribution of these components was studied and the form of occurrence was determined. The chemical characterisation shows that high levels of natural mineral dust components (e.g. Al, Fe, Mg, Ti, Sr, Ca) are simultaneously recorded in PM10 and PM2.5 at all sites during African episodes. Other interesting findings are: 1) a marked seasonal evolution of nitrate levels and grain size distribution due to the occurrence of ammonium-nitrate in autumn-winter, 2) an excess of Na with respect to the Na/Cl marine ratio in summer owing to reactions of acids with sea salt, and 3) high background levels of ammonium-sulphate in summer. Moreover, the levels of elemental, organic and mineral carbon were determined. At the rural site, the PM10 annual mean reaches 22µg/m3, the main contributions being secondary particles from industrial emissions (27% of PM10), vehicle exhausts (14-23%), natural mineral dust (23%) and sea spray (5-9%). At the urban kerbside station, the PM10 annual mean reaches 49µg/m3, the main contributions being vehicle exhausts (35-45% of PM10), secondary particles from industrial emissions (24-31%), natural + road dust (25%) and sea spray (4-6%). At the urban kerbside station, the PM2.5 annual mean reaches 34µg/m3, the main contributions being vehicle exhausts (41-53% of PM2.5), secondary particles from industrial emissions (29-35%) and mineral dust (9-11%). These results have important implications for the implementation of the PM10 EU standards. The natural load in ambient PM10 levels in Eastern Spain accounts for 30-40% of the 2010 EU annual PM10 limit value (20µg/m3). In this region it will not be easy to meet this limit value given that the annual PM10 levels are in the range 17-20µg/m3 at rural, 30-45µg/m3 at urban and 45-60µg/m3 at industrial sites. The high background levels of PM10 in this region are favoured by the specific orographic and meteorological context of the Mediterranean and by the high load of mineral dust caused by the soil re-suspension and the frequent occurrence of African dust events. At rural sites, 2-5 exceedances of the EU daily PM10 limit value (50µg/m3) are recorded every year during African dust outbreaks. On average, 15 African induced and 40-80 non-African induced exceedances of the EU daily PM10 limit value are recorded every year at the urban kerbside stations. The parameter selected for PM monitoring is a key factor. Most of the PM species resulting from combustion and vehicle exhaust emissions have a fine size distribution (<2.5µm), with exception of nitrate in summer, whereas sea spray and mineral dust present a coarse size distribution. The interference of African dust in the PM monitoring is significantly reduced when PM2.5 instead of PM10 is monitored. Natural mineral dust concentrations during African episodes are in the ranges 20-30µg/m3 in PM10 and 10-15µg/m3 in PM2.5. However, PM2.5 is not a suitable parameter for PM monitoring in all environments. The selection of PM10 or PM2.5 should be conditioned by the type of anthropogenic activity. At urban sites, PM2.5 contains mainly vehicle exhaust products, whereas the road traffic dust principally occurs in the 2.5-10µm fraction. PM2.5 is not a suitable parameter for monitoring some industrial activities (e.g. ceramics, cement production or mining) with primary PM emissions in the 2.5-10µm range.

148f. / Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2013-03-22T17:35:21Z No. of bitstreams: 1 TESE VERSÃO FINAL_Rogete.pdf: 3403393 bytes, checksum: 8ad0a12697759237a2a80d8d5568a3c8 (MD5) / Approved for entry into archive by Ana Hilda Fonseca(anahilda@ufba.br) on 2013-04-19T14:20:42Z (GMT) No. of bitstreams: 1 TESE VERSÃO FINAL_Rogete.pdf: 3403393 bytes, checksum: 8ad0a12697759237a2a80d8d5568a3c8 (MD5) / Made available in DSpace on 2013-04-19T14:20:43Z (GMT). No. of bitstreams: 1 TESE VERSÃO FINAL_Rogete.pdf: 3403393 bytes, checksum: 8ad0a12697759237a2a80d8d5568a3c8 (MD5) Previous issue date: 2013 / CAPES / O material particulado atmosférico (MP) é um dos principais poluentes do ar, este pode ser emitido por fontes naturais e antrópicas. Em ambientes urbanos o tráfego de veículos é um dos grandes responsáveis por sua emissão. Em sua composição estão associadas inúmeras espécies químicas, dentre as quais se destacam metais e metalóides. A origem destas espécies através do tráfego está relacionada a várias fontes, tais como, produtos de combustão do combustível e óleo; produtos de desgaste de pneus, lonas de freio, rolamentos; materiais de construção das vias de tráfego; e ainda a ressuspensão da poeira do solo. As frações mais finas do MP são as mais nocivas e a exposição a estas partículas é responsável por vários efeitos à saúde e estão associadas ao aumento de riscos de doenças respiratórias e cardiovasculares e problemas reprodutivos. Especialmente os metais podem causar câncer, mutações e problemas neurológicos. Neste trabalho, as concentrações de partículas em suspensão foram determinadas por meio de técnica gravimétrica; e as concentrações atmosféricas dos elementos traço As, Ba, Ca, Cd, Co, Cu, Fe, Hg, Mg, Mn, Ni, Pb, Sb, Sn, V e Zn, nas frações MP10 e MP2,5 coletadas no Terminal Rodoviário da Lapa, foram determinadas usando as técnicas de ICP-MS e ICP OES. As amostras de MP10 e MP2,5 do ano de 2010, foram coletadas sobre filtros de microfibra de quartzo em amostradores de grande volume (Hi-Vol). As amostras de MP10 coletadas em 2005 em outro estudo, foram utilizadas neste trabalho com a finalidade principal de se investigar a composição elementar do MP no período de transição B0 (2005) para B5 (2010). Para a seleção do procedimento de extração, com vistas ao tratamento das amostras de MP, foram realizados alguns experimentos e dentre estes, a mistura de 2 mL HNO3, 1 mL de H2O2 e 5 mL H2O, se mostrou adequada produzindo respostas satisfatórias. A validação do método garantiu recuperações na faixa de 83% a 114%. Os limites de quantificação do método nas determinações realizadas por ICP-MS foram estabelecidos entre 0,02 e 1,82 ng m-3 e nas determinações por ICP OES entre 1,9 e 896 ng m-3. Os resultados da concentração de partículas em suspensão para MP10 e MP2,5, apresentaram valor médio, respectivamente, de 134 μg m-3 e 83,2 μg m-3. Entre os elementos traço minoritários, as maiores concentrações médias encontradas em 2010, foram para Hg, Ni, Pb, Sn e V cujos valores para MP10 foram, respectivamente, 4,52; 4,53; 7,33; 4,41 e 5,68 ng m-3; e para MP2,5 foram, respectivamente, 2,68; 3,01; 4,57; 1,32 e 2,96 ng m-3. Entre os elementos majoritários as maiores concentrações encontradas em 2010, foram para Ba, Ca, Fe e Mg, cujos valores médios foram, respectivamente, para MP10, 587; 5260; 5190 e 1907 ng m-3 e MP2,5, 165; 2759; 2101; 947 ng m-3. A avaliação das concentrações dos elementos traço por turno em 2010 mostrou que nos turnos da manhã e tarde em conjunto, a concentração dos elementos traço compreendeu aproximadamente entre 58% a 87% do total emitido na fração MP10; e entre 62% a 85% na fração MP2,5. Os cálculos do fator de enriquecimento revelaram que os elementos de origem antrópica no MP em suspensão, portanto considerados enriquecidos, foram As, Ba, Cd, Cu, Hg, Pb, Sb, Sn e Zn. A análise multivariada permitiu identificar os elementos que caracterizaram as emissões do MP e a influência do tráfego conforme os turnos de amostragem. E ainda indicou que as diferenças entre as frações MP10 de 2005 e 2010, correspondentes ao período de transição de B0 para B5, foram relacionadas às concentrações de Cd, Mn, Cu e Hg. / Salvador

Made available in DSpace on 2016-06-02T19:55:43Z (GMT). No. of bitstreams: 1 TeseMCRF.pdf: 11090482 bytes, checksum: acd91fb03f2001e7f8897df596f44b7d (MD5) Previous issue date: 2005-05-24 / Universidade Federal de Minas Gerais / The removal of submicron particles from gaseous streams is becoming an increasingly important operation, both in industrial (nanotechnology) as well as in occupational (inhalation of particula te matter) applications. Among the equipments commonly employed for the removal of particula tes of the gaseous stream, the electrostatic precipitator, ESP, is the one capable of removing particles of such size with high efficiency. Furthermore, it has other advantages as the low pressure drop and the flexibility of working at higher temperatures. Therefore, the objective of this research was to evaluate the influence of operational and design parameters in the efficiency of particle removal of a plate-wire ESP operating in the removal of submicron particles. The precipitator was built in acrylic, with copper plates as collecting electrodes and stainless steel wires as discharge electrodes. The study was divided in two stages: the first studied the collection of PM2.5 (high risk particle matter), using alumina, with median diameter of 0.6 mm and maximum diameter of 2.5 mm as test powder, while the stage 2 focused the nanometric range, utilizing particles of sodium chloride, with diameters between 8 and 100 nm. In stage 1, the project parameters analyzed were duct length (L), diameter of the discharge electrodes (2r) and spacing between them (2c); the operational variables were the electric field (E) and the air velocity (v). Each variable was evaluated in two levels, whose values were Lne = 15 and 30 cm; 2r = 0.045 and 0.025 cm; 2c = 4 and 2 cm; E = 5 and 8 kV/cm and, finally, v = 0.5 and 1.0 m/s. The process performance was evaluated through the analysis of the global efficiency of removal of the particula te matter, obtained through isokinetic sampling. In stage 2, the project parameter analyzed were the duct length (Lne), the ratio s/2c and the distance between the collection plates (2s) and the operational variables were the air velocity (v) and current density (j). Each operation variable was evaluated in three levels, whose values were v = 0.125, 0.25 and 0.50 m/s and j = 1.8, 2.8 and 3.8 mA/m2. The project parameters were studied in two leve ls, Lne = 15 and 30 cm and 2s = 0.04 and 0.06 m. The process performance was evaluated through the analysis of the removal efficiency of the particulates obtained by particle counting, with the use of the Condensation Particle Counter 3007, from TSI. It was observed that the precipitator possesses high collection efficiency, even in the nanometric size range, were efficiencies larger than 99% were obtained, depending on the used configuration. As expected, the increase in air velocity, as well as the decrease of the collecting plate length and of the generated current caused a decrease in the efficiency. Conversely, larger spacing between plates resulted in an increment in the efficiency, phenomenon also observed by some other researchers for larger particles. The ratio s/2c did not show a clear tendency in particle removal. When compared to models from the literature, the one that offered the better adjustment to the experimental data was the classic Deutsch model when used with a drag coefficient given by a modified version of the Li and Wang (2003a e b) equation. / A remoção de partículas submicrométricas de correntes gasosas tem-se constituído numa operação cada vez mais importante, tanto em aplicações industriais (nanotecnologia) quanto ocupacionais (inalação de material particulado). Dentre os equipamentos comumente empregados para a remoção de material particulado da corrente gasosa, o precipitador eletrostático é o que se apresenta mais apto a remover partículas de tal tamanho com alta eficiência. Desse modo, o objetivo desta pesquisa foi avaliar a influência dos parâmetros de operação e de projeto na eficiência de remoção de um precipitador eletrostático do tipo placa-fio, operando na remoção de partículas sub e nanométricas. O precipitador foi construído em acrílico e possui placas coletoras de cobre e eletrodos de descarga de aço inox. O estudo foi dividido em duas etapas: a primeira estudou a coleta de PM2,5 (material inalável de alto risco), utilizando alumina, com diâmetro mediano de 0,6 mm e diâmetro máximo de 2,5 mm, enquanto a etapa 2 focou a faixa nanométrica, utilizando partículas de cloreto de sódio, com diâmetros entre 8 e 100 nm. Na etapa 1, os parâmetros de projeto analisados foram comprimento do duto (Lne), diâmetro dos eletrodos de descarga (2r) e espaçamento entre os mesmos (2c) e as variáveis de operação foram o campo elétrico (E) e a velocidade de escoamento do ar (v). Cada variável foi avaliada em dois níveis, cujos valores foram Lne = 15 e 30 cm; 2r = 0,045 e 0,025 cm; 2c = 4 e 2 cm; E = 5 e 8 kV/cm e, finalmente, v = 0,5 e 1,0 m/s. O desempenho do processo foi avaliado através da análise da eficiência global de remoção do material particulado, obtida através de amostragem isocinética. Na etapa 2, os parâmetros de projeto analisados foram L, relação s/2c e distância entre as placas de coleta (2s) e as variáveis de operação foram v e densidade de corrente (j). Cada variável de operação foi avaliada em três níveis, cujos valores são v = 0,125, 0,25 e 0,50 m/s e jne = 1,8, 2,8 e 3,8 mA/m2. Já os parâmetros de projeto foram estudados em dois níveis, Lne = 15 e 30 cm e 2s = 0,04 e 0,06 m. O desempenho do processo foi avaliado através da análise da eficiência de remoção do material particulado, obtida através da contagem de partículas. Observou-se que o precipitador possui grande capacidade de coletar partículas até mesmo na faixa nanométrica, obtendo eficiências para alguns casos maiores que 99%, dependendo da configuração utilizada. Como esperado, o aumento da velocidade do gás, bem como a diminuição do comprimento das placas coletoras e da corrente gerada, causaram uma diminuição da eficiência. Em contrapartida, o maior espaçamento entre as placas acarretou um incremento na eficiência, fenômeno também observado por alguns outros pesquisadores para partículas maiores. A relação s/2c não apresentou uma tendência clara na remoção do material particulado. Quando avaliados os modelos presentes na literatura, aquele que melhor se ajustou aos dados experimentais foi o modelo clássico de Deutsch, quando utilizado o coeficiente de arraste dado por uma versão modificada da equação de Li e Wang (2003a e b).