Sustentabilidade ambiental da criação de camarões de água doce e uso do aguapé no tratamento dos efluentes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Sewage sludge gasification. Dolomite performance under different operating conditions

Gasification is a technology that can replace traditional management alternatives used up to date to deal with this waste (landfilling, composting and incineration) and which fulfils the social, environmental and legislative requirements. The main products of sewage sludge gasification are permanent gases (useful to generate energy or to be used as raw material in chemical synthesis processes), liquids (tars) and char. One of the main problems to be solved in gasification is tar production. Tars are organic impurities which can condense at relatively high temperatures making impossible to use the produced gases for most applications. This work deals with the effect of some primary tar removal processes (performed inside the gasifier) on sewage sludge gasification products. For this purpose, analysis of the gas composition, tar production, cold gas efficiency and carbon conversion were carried out. The tests were performed with air in a laboratory scale plant consisting mainly of a bubbling bed gasifier. No catalyzed and catalyzed (10% wt of dolomite in the bed and in the feeding) tests were carried out at different temperatures (750ºC, 800ºC and 850ºC) in order to know the effect of these parameters in the gasification products. As far as tars were concerned, qualitative and quantitative tar composition was determined. In all tests the Equivalence Ratio (ER) was kept at 0.3. Temperature is one of the most influential variables in sewage sludge gasification. Higher temperatures favoured hydrogen and CO production while CO2 content decreased, which might be partially explained by the effect of the cracking, Boudouard and CO2 reforming reactions. At 850ºC, cold gas efficiency and carbon conversion reached 49% and 76%, respectively. The presence of dolomite as catalyst increased the production of H2 reaching contents of 15.5% by volume at 850 °C. Similar behaviour was found for CO whereas CO2 and CnHm (light hydrocarbons) production decreased. In the presence of dolomite, a tar reduction of up to 51% was reached in comparison with no catalyzed tests, as well as improvements on cold gas efficiency and carbon conversion. Several assays were developed in order to test catalyst performance under more rough gasification conditions. For this purpose, the throughput value (TR), defined as kg sludge “as received” fed to the gasifier per hour and per m2 of cross sectional area of the gasifier, was modified. Specifically, the TR values used were 110 (reference value), 215 and 322 kg/h·m2. When TR increased, the H2, CO and CH4 production decreased while the CO2 and the CnHm production increased. Tar production increased drastically with TR during no catalysed tests what is related to the lower residence time of the gas inside the reactor. Nevertheless, even at TR=322 kg/h·m2, tar production decreased by nearly 50% with in-bed use of dolomite in comparison with no catalyzed assays under the same operating conditions. Regarding relative tar composition, there was an increase in benzene and naphthalene content when temperature increased while the content of the rest of compounds decreased. The dolomite seemed to be effective all over the range of molecular weight studied showing tar removal efficiencies between 35-55% in most cases. High values of the TR caused a significant increase in tar production but a slight effect on tar composition.

Modelling sugar beet water use in Spain

Crop production has a great contribution to water use and abstraction. Sugar beet is an important crop in irrigated land in Spain and covers 70.000 Ha. Crop and resources management are key factors for a sustainable agriculture. The aim of this work is to mode the sugar beet crop growth and water consumption in order to quantify crop water use and virtual water content in different growing conditions.

Pouillés du diocèse de Lisieux,

Mode of access: Internet.

Examen de l'administration du diocèse de Dijon, ou Recueil des articles publiés dans le Journal de la Côte-d'Or au sujet de la démission de MM.les vicaires-généraux et des dernières lettres pastorales de m. l'évêque [Claude Rey].

Mode of access: Internet.

Le grand paroissien latin, contenant l'office de l'Église, pendant toute l'année, à l'usage du Diocèse d'Évreux, impriné par ordre de Monseigneur l'Évêque.

Mode of access: Internet.

Gesta pontificum camaracensium : Gestes des évêques de Cambrai de 1092 à 1138 /

"Liste alphabétique des sources": p. xxxv-xxxviii.

Cartulaire de l'évêche d'Autun, connu sous le nom de Cartulaire rouge.

"Publication de la Société éduenne".

Champs de bataille: experiences et imaginaires

This contribution takes as its starting point the original conception of the overall research project which sought to examine the ‘battle’ as an event and a cultural act. It examines the representation of violence by non-combatants – who are in any case implicated in the act of war – as well as by combatants themselves. It does, however, also slightly subvert the original proposition of the war narrative as a historical source, towards the idea of the war narrative as a source of artistic representation, as well as towards the notion of ‘narrative’ understood in its broadest sense, towards visual as well as written narratives. The primary focus is however, a specific site of the violence perpetrated and endured by soldiers, the battlefield. One of the fundamental questions posed by the analysis here concerns the issue of the representation and of the reality of the battlefield, and of the reception of the expression of violence. Is representation in fact the only authentic way to seize and to try to understand violence? These questions, and some of the examples used in the first section dealing with the ‘experience’ of the battlefield, have their origins in work conducted for two decades within the international and interdisciplinary research group, the ‘Group for War and Culture Studies’, and therefore concern the bases of a cultural approach to the study of war. In the second section, the analysis moves from the notion of experience to the work of the imagination with a reading of various battlefields created by the contemporary artist Cozette de Charmoy; these are imaginary battlefields certainly, but ones which viscerally engage the body of the soldier and which seem to enable the reader/spectator to access a collective experience. Finally, the question is raised of whether representation actually becomes performative, if it becomes the experience itself, and a way not to ‘see’ that experience, but to ‘know’ it.

Un registre collaboratif (praticiens, chercheurs, étudiants, habitants) de penser et faire la ville

International audience