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Mons-lez-Liège, Belgium

El Gout R.,University Mohammed Premier | Khattach D.,University Mohammed Premier | Houari M.-R.,University Mohammed Premier | Kaufmann O.,Faculte Polytechnique de Mons | Aqil H.,University Mohammed Premier
Journal of African Earth Sciences | Year: 2010

Many years ago, geophysical surveys (gravity and aeromagnetic) were initiated for economic investigation and recently the analysis of gravity and magnetic anomalies are used as a powerful tool for the geological mapping. The present study is based on various filtered maps of gravity and aeromagnetic anomalies of north-eastern Morocco (NEM) in order to highlight its main structural features. Filtering techniques such as horizontal gradient, upward continuation and Euler deconvolution were used to map structural lineaments in NEM. The obtained structural map is consistent with many faults already recognized or supposed by traditional structural studies, and highlights new major accidents by specifying their layout and dips. © 2010 Elsevier Ltd.

Gooijer L.,National Institute for Public Health and the Environment | Cornil N.,Faculte Polytechnique de Mons | Lenoble C.L.,INERIS
Process Safety and Environmental Protection | Year: 2012

In order to compare the quantitative risk assessment (QRA) methods for land use planning and licensing used in France, the United Kingdom, The Netherlands and the Walloon Region of Belgium, a benchmark exercise was performed. Based on a description of a fictitious LPG storage plant, INERIS from France, HSE from the United Kingdom, the Faculté Polytechnique de Mons from the Walloon Region of Belgium and the RIVM from The Netherlands used their own quantitative risk assessment approach to perform the exercise. The risk assessment approaches to determine third party risks of a LPG plant used by the four partners are very different. In France the assessment is based on a specific on-site analysis performed by experts. HSE uses a simple consequence based approach to determine safety distances. In The Netherlands and the Walloon Region a generic and standardized method for determining the risk contours is used. The differences relate to the calculation methodologies and the types of consequences that are calculated (such as lethal effects or irreversible effects). Despite the differences, the methods yield to similar safety distances between houses and companies: distances between 200 and 280 m. However, similar safety distances can still have different policy implications. For instance, the safety distances in The Netherlands and France are used as limit values, whereas in Belgium and the United Kingdom they are used to give an advice. © 2011 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Yans J.,University of Namur | Gerards T.,University of Liege | Gerrienne P.,University of Liege | Spagna P.,Faculte Polytechnique de Mons | And 4 more authors.
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2010

Pedogenic nodules, calcitic shells, dispersed organic carbon and bulk rocks affected by low diagenesis are judged to be reliable tools for carbon-isotope chemostratigraphy. Up to now no systematic study has been carried out to check the reliability of fossil wood material for carbon-isotope chemostratigraphy in terrestrial settings. The 235-m thick Wealden facies sediments of the Danube-Bouchon quarry at Hautrage (Hautrage Clays Formation, Mons Basin, Belgium) encompass dark to grey clays and sands, rich in organic matter and coalified-charcoalified fragments of fossil wood, deposited in an alluvial plain during middle Barremian to earliest Aptian. We measured and compared the carbon-isotope ratios of 110 levels of the stratigraphic succession for dispersed organic carbon (δ13CDOC), and fossil wood (δ13CWOOD) collected in the same geological level. In the whole succession, the averages of δ13CDOC and δ13CWOOD have a significant difference of about 0.9‰. The δ13CWOOD is usually heavier than the δ13CDOC, which is consistent with measurements on different constituents of modern trees (branches versus leaves and tissues). In one single stratigraphic level, the variability of δ13CWOOD is much higher (up to 7.3‰) than that of δ13CDOC (0.4‰). Four main causes may explain these results. Firstly, the δ13CDOC averages the isotopic signal of different compounds and tissues (such as leaves, seeds, cuticles) as they become mixed and dispersed. The δ13CWOOD reflects the carbon-isotope ratio of a small part only of one single tree, which is a complex system with δ13C variations over a range of 4‰. Secondly, there is strong δ13C variability between different species of plants. In Hautrage, several gymnosperm genera were collected (including Podocarpoxylon, Taxodioxylon, Brachyoxylon, and Thujoxylon) and numerous fern taxa. Thirdly, coalification and charcoalification can affect the δ13C of the DOC and the various kinds of woods in a different way. Fourthly, the wood fragments may be reworked several times from more ancient geological levels, especially in the alluvial plain environment of Hautrage where thick levels of fluviatile coarse sand deposits are observed. However, in the whole succession, both δ13CWOOD and δ13CDOC curves show similar trends. This suggests that carbon-isotope curves on fossil wood can be matched to carbon-isotope curves on DOC. For the whole trend fossil wood is a relatively good chemostratigraphic tool when sufficient samples are measured in the succession. Whenever possible both control of the wood taxa, and estimation of degree of (char)coalification are however recommended. In one single level, charcoal has more stable δ13CWOOD values than δ13CWOOD of coalified fragments. The δ13C positive trend can be due to several causes, including global pCO2 variations and/or regional changes and/or local environmental conditions in the alluvial plain. If global, the dating of the Hautrage succession may be refined to the late Early Barremian-early Late Barremian by matching palynological and carbon-isotope chemostratigraphical data. © 2010 Elsevier B.V. All rights reserved.

Darracq G.,National Graduate School of Chemistry, Rennes | Darracq G.,European University of Brittany | Couvert A.,National Graduate School of Chemistry, Rennes | Couvert A.,European University of Brittany | And 9 more authors.
Journal of Chemical Technology and Biotechnology | Year: 2010

BACKGROUND: Hydrophobic volatile organic compounds(VOCs), such as toluene,dimethyl sulfide (DMS)anddimethyldisulfide (DMDS), are poorly soluble inwater and classical air treatment processes like chemical scrubbers are not efficient.An alternative technique involving an absorption step in an organic solvent followed by a biodegradation phase was proposed. The solvent must fulfil several characteristics, which are key factors of process efficiency, andaprevious study allowedpolydimethylsiloxane (or PDMS, i.e. silicone oil) to be selected for this purpose. The aim of this paper was to determine some of its characteristics like absorption capacity and velocity performances (Henry's constant, diffusivity and mass transfer coefficient), and to verify its non-biodegradability. RESULTS: For the three targeted VOCs, Henry's constants in silicone oil were very low compared to those in water, and solubility was infinite. Diffusivity values were found to be in the range 10-10 to 10-11 m2 s-1 andmass transfer coefficients did not show significant differences between the values in pure water and pure silicone oil, in the range 1.0 × 10-3 to 4.0 × 10 -3 s-1 for all the VOCs considered. Silicone oil was also found to be non-biodegradable, since its biological oxygen demand (BOD5) value was zero. CONCLUSION: Absorption performances of silicone oil towards toluene, DMS and DMDSwere determined and showed that this solvent could be used during the first step of the process. Moreover, its low biodegradability and its absence of toxicity justify its use as an absorbent phase for the integrated process being considered. © 2010 Society of Chemical Industry.

Dumont E.,Ecole des Mines de Nantes | Darracq G.,National Graduate School of Chemistry, Rennes | Darracq G.,European University of Brittany | Couvert A.,National Graduate School of Chemistry, Rennes | And 9 more authors.
Chemical Engineering Journal | Year: 2010

The main objective of this work was to propose a model able to predict the partition coefficient of odorous or toxic gaseous pollutants (dimethylsulphide, dimethyldisulphide and toluene) in water/silicone oil mixtures. Experimental measurements using a static headspace method were carried out for pure water (Hvoc,water), for pure silicone oil (Hvoc,solvent) and for mixtures of varying composition (Hvoc,mixture). The dramatic decrease in the partition coefficient (Hvoc,mixture) with oil addition clearly showed a deviation from linearity, which was more pronounced for increasing Hvoc,water/Hvoc,solvent ratios. Moreover, experiments using a dynamic absorption method underlined that the absorption capacity of a biphasic water/silicone oil mixture can be classed as the absorption capacity of a pseudo-homogeneous phase whose physical properties (molecular weight and density) can be calculated from the physical properties of water and solvent, and balanced using the " equivalent absorption coefficients" Hvoc,mixture/Hvoc,water and Hvoc,mixture/Hvoc,solvent. An " equivalent absorption capacity" concept is then proposed, which should be useful to design absorption units using two-phase liquid mixtures for the treatment of industrial air loaded with volatile organic compounds. © 2010 Elsevier B.V.

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