https://www.peren-revues.fr/pollutionatmospherique/1426 Publications de Auteurs Jean Carré fr 0 https://www.peren-revues.fr/pollutionatmospherique/3071 Nous avons étudié les conditions d'analyse de COV dans des atmosphères industrielles avec des mélanges pouvant contenir jusqu'à 29 COV (hydrocarbures aliphatiques et aromatiques, esters, hydrocarbures halogénés, amines, alcools et autres composés oxygénés) à des teneurs pouvant aller jusqu'à 300 mg.m-3. Nous avons travaillé dans deux directions :- l'analyse par chromatographie en phase gazeuse après piégeage sur charbon actif et extraction par sonication avec le sulfure de carbone ; - l'analyse par microchromatographie portable.La première technique donne une valeur moyenne sur 8 heures des concentrations de COV et la seconde fournit une valeur quasi instantanée.Nous avons essayé d'optimiser les deux techniques et avons comparé les résultats obtenus avec ces deux techniques pour l'analyse de l'atmosphère d'ateliers de manipulation de COV divers en tenant compte des variations de concentration en fonction de l'emplacement dans l'atelier. Les résultats sont concordants et nous allons reprendre nos mesures avec plusieurs appareils portables différents capables de mesurer de plus faibles concentrations de COV. Our study deals with analysis conditions of VOCs in industrial atmospheres. Some of these mixtures may contain upto29 VOCs (aromatic and aliphatic hydrocarbons, esters, halogenated hydrocarbons, amines, alcohols and other oxygenated compounds) with contents of up to 300 mg.m-3.We proceeded in two ways: - gaseous phase chromatographie analysis after trapping inactivated carbon and extraction by sonication with carbon disulfide; - analysis with a portable microchromatograph. The first technique gives an average value over 8hours of VOC concentrations and the second gives a almost instantaneous value. We tried to optimize the two techniques.We developed operative conditions for an extraction and analysis method of 29 VOCs encountered in the working environment. The method was applied to the dosage of solvents trapped by GABIE badges, worn by workers during one day.We introduced extraction coefficients taking into account all systematic errors. We carried out a microchromatographic analysis after aspiration in tigh containers since microchromatographs cannot be used in inflammable atmospheres.We compared the results obtained with each of the Iwo techniques when analysing the atmosphere of different workplaces in which a variety of VOCs are manipulated, taking into account the variations of VOC concentration in different parts of the workplace. The results obtained corroborate each other and we intend to carry out new measurements (with low concentrations of VOCs) using different microchromatographs. mer., 05 mars 2014 14:31:06 +0100 mer., 13 juil. 2016 15:09:17 +0200 https://www.peren-revues.fr/pollutionatmospherique/3071 https://www.peren-revues.fr/pollutionatmospherique/2641 Une étude bibliographique a été effectuée sur la nature des émissions gazeuses issues des décharges d'ordures ménagères, sur le prélèvement de ces gaz ou le piégeage des composés organiques volatils (COV) contenus pour analyse au laboratoire, ainsi que sur les techniques de dosage sur site avec du matériel portable. Ceci nous a permis de faire un choix, de valider et étalonner les techniques retenues. Les résultats obtenus sur quatre s1tes européens ont servi à dégager la signification de chaque type de mesure (observation d'une pollution chronique ou suivi d'un pic de pollution). L'examen de ces résultats nous permet de proposer une méthodologie analytique de suivi des rejets aériens de COV issus des décharges d'ordures ménagères. A bibliographical study was made about the emissions of volatile organic compounds (VOCs) from municipal solid waste (MSW) landfills and about sampling, trapping and extraction for analysis. We have also studied the possibilities of using portable analysers in landfills. A choice between these possibilities was made and we have standardized the devices of the following techniques: static trapping with active charcoal tubes RADIELLO; dynamic trapping with active charcoal tubes SKC; extraction by sonication with carbon disulfide and analysis by GC/MS coupling: on-site chromatographie analysis with two different portable devices (PHOTOVAC VOYAGER and μGC AGILENT Technologies apparatus). The results obtained in four European landfills were studied (chronical pollution or episodic pollution). Lastly, we propose a methodology of study of VOC's emissions from MSW landfills. mer., 05 févr. 2014 11:44:39 +0100 mer., 16 déc. 2015 12:03:09 +0100 https://www.peren-revues.fr/pollutionatmospherique/2641 https://www.peren-revues.fr/pollutionatmospherique/1414 Le travail présenté a pour but dʼétudier la pollution aérienne par les BTEX et alcanes légers dans la ville de Bourgas (Bulgarie). Les principales sources recensées étant une raffinerie proche et la circulation automobile, le choix a été fait (après étude du comportement à lʼévaporation des composants de carburants) de suivre uniquement la pollution par les BTEX et alcanes (heptane, octane, nonane) ; les premiers, en particulier le benzène, à cause de leur effet nocif sur la santé humaine, les seconds à cause de leur impact sʼajoutant à celui des BTEX sur la quantité dʼozone troposphérique. Le positionnement des points de prélèvement a été fait en sʼaidant dʼune campagne préliminaire de prélèvements statiques sur charbon actif. Des prélèvements dynamiques ont ensuite été effectués également par accumulation sur charbon actif.Les analyses ont été faites par couplage GC/MS après extraction au sulfure de carbone des polluants piégés. Les résultats ainsi obtenus montrent une pollution plus grande au niveau des zones à forte densité de circulation avec de brusques variations des concentrations en polluants dues vraisemblablement aux modifications rapides des conditions de circulation urbaine, une pollution plus importante au nord quʼau sud de la ville traduisant lʼimpact de la raffinerie, une pollution maximale en centre-ville (valeurs moyennes sur 15 jours de lʼordre de 500 μg.m–3 en BTEX) et une pollution minimale au voisinage de la mer Noire ou du lac de Bourgas (valeurs moyennes sur 15 jours de lʼordre de 50 μg.m–3 en BTEX) qui montrent bien les influences opposées de lʼémission et de la dispersion.Lʼexamen du dépassement des normes bulgares dʼexposition de la population a mis en évidence le caractère saisonnier de cette pollution et le calcul de la moyenne obtenue sur lʼensemble des prélèvements pour la concentration en benzène indique que le niveau de pollution est voisin de celui des villes du sud de lʼEurope. A study of the air pollution in BTEX and alcanes (heptane, octane, nonane) of the city of Burgas was carried out with dynamic samplings by pollutant accumulation on active charcoal (a preliminary study with static samplings had already been done before this study), to complete the existing data that are very fragmentary and almost nonexistent in the territory of the city.The purpose of sampling multiplication was to map pollutants and their time development in order to allow the modelling of pollution (transmission and broadcasting) and the optimization of a more complete observation network within the framework of the Bulgarian thesis of Madam Naydenova. The results published in this thesis were based on measures carried out between 2000 and 2004 and will be used to defend the thesis, planned for 2007.The collected information (the density of the traffic and the kind of vehicles) corresponds to the 2000-2004 period, but an extrapolation is done for the current period. At the same time the impact was evaluated according to the Bulgarian environmental norms that were in force between 2000 and 2004. These norms were more strict than the European norms (hourly average and annual concentrations) and therefore gave more complete information.The main potential sources of pollutants are: the LUKOIL refinery situated at about 7 km to the North West of the city (average production at about 7 million tons of oil products), two industrial zones to the North and to the South inside the cityʼs territory, the local and transit car traffic to the south Bulgarian Black Sea coast.The preliminary campaign of static samplings in the city of Burgas and its surrounding area confirmed these expectations while showing the weakest pollution of the dwelling neighborhoods (except those close to the refinery) in comparison with the pollution of the zones with high traffic density. We had therefore decided to do measures inside the territory of the city with dynamic samplings by accumulation on active coal to high debit (a litre.min–1), following the Bulgarian analytical norm, having good sensitiveness.The sampling points were placed while taking into account the pollution sources and system of dominant breezes in sea edge. The extraction was done with carbon disulfide and the analysis by coupling GC/MS. The behavior to the evaporation of the components of fuels (refinery and petrol station emissions) and the used sampling and analysis techniques were the same as our BTEX and heptane, octane, nonane study. The obtained results from the dynamic samplings showed a bigger dispersion in comparison with the static samplings, which is logical.There was a correlation between the variations of the concentration in alcanes and BTEX, the alcanes concentrations were at a higher level.There is a relation between human activity and pollution – the observed concentrations were higher on working days than on weekends (particularly on Sundays). The average "dynamic" values confirm the observed tendencies to support the static samplings and at the same time these results allowed a brief mapping (concentration level expressed by variation of the base level for each sample point). This outline allows the following conclusions:-a bigger pollution in zones with high density of the car traffic;-a more substantial pollution in the North than in the South of the city because of the LUKOIL refinery;-a maximal pollution in the center of the city (500 μg.m–3 for BTEX) and a minimal pollution on the Black Sea or the Burgas lake coasts (50 μg.m–3 for BTEX) that show the influence of the opposition between emission and dispersion.These observations were based on the Bulgarian hourly environmental norms for benzene (10 μg.m–3). If we perform an average value of the 47 dynamic samplings, we obtain an average concentration of benzene 14,3 μg.m–3, the reliable values for the samplings were dispersed regularly on weekdays, including weekends. In this way Burgas is on the same pollutant level as other South European cities.The pollution is higher in winter than in summer, despite the bigger summer traffic (the city of Burgas is a tourist center and there is an increased summer transit).In our opinion this is the result of the functioning of the heating installations in the wintertime and of a better dispersion of the pollutants in summertime.These samples were taken between 2001 and 2004. The number of registered cars increases steadily (about 8% per year). This fact did not have an important influence between 2001 and 2004, because the rise in the traffic increase was compensated by a partial renewal of the vehicles with more modern ones. mer., 15 mai 2013 11:31:02 +0200 mer., 14 oct. 2015 16:16:16 +0200 https://www.peren-revues.fr/pollutionatmospherique/1414