Littérature scientifique sur le sujet « Cokeria »

During recent studies of phylogenetic relationships within Eriphioidea (sensu Ng et al. 2008), we recovered molecularevidence that the genus Platyxanthus A. Milne-Edwards, 1863, was not monophyletic. This prompted detailedmorphological examination of the group, which confirmed that clear differences in characteristics of the carapace, firstmale pleopod, antennae, antennules, epistome, abdomen, and thoracic sternum serve to separate the species ofPlatyxanthus into three distinct groups. Comparison of the type material of Peloeus cokeri (Rathbun, 1930), (formerlyPlatyxanthus cokeri) to Peloeus armatus Eydoux & Souleyet, 1842, indicated that P. cokeri is a junior synonym of P.armatus and that Gordonoxanthus Števčić, 2011 (type species Platyxanthus cokeri Rathbun, 1930) is thus a juniorsynonym of Peloeus. Danielethus n. gen. is described to accommodate Platyxanthus patagonicus A. Milne-Edwards,1863, and Platyxanthus crenulatus A. Milne-Edwards, 1863. A key to the known genera and species of the family Platyxanthidae Guinot, 1977 is provided.

L'écotoxicité d'un sol contaminé par les HAP et provenant d'une ancienne cokerie a été étudiée. La contamination du sol par les 16 HAP s'élevait à 2634  241 mg/kg de sol exprimé en poids sec. Des métaux ont été trouvés également mais à concentration faible, de l'ordre des niveaux géologiques en Lorraine, à l'exception du mercure. Les résultats de toxicité des lixiviats soulignent la sensibilité des deux essais de toxicité chronique - sur la reproduction des cladocères et la division algale. Un caractère mutagène du lixiviat a été enregistré avec le test d'Ames et le test Mutatox ; mais aucune réponse n'a été notée avec le test Umu moins sensible. La germination des plantes testées n'est pas affectée par le sol de cokerie, contrairement à la croissance. Les résultats des essais d'écotoxicité terrestre témoignent d'une toxicité élevée du sol étudié sur la survie et la reproduction des collemboles, sur la reproduction des vers de terre et la survie des juvéniles. L'influence du sol de dilution utilisé pour tester différentes concentrations du sol contaminé a été étudiée en comparant un sol contrôle artificiel (ISO) et un sol naturel de prairie. La comparaison des réponses des invertébrés au sol de cokerie fait apparaître une sensibilité plus élevée en sol artificiel ISO qu'en sol naturel. Il ne semble pas que le transfert des HAP du sol à la biomasse végétale ou à celle des invertébrés pose des problèmes d'accumulation, compte tenu des facteurs enregistrés nettement inférieurs à 1. Les essais de bioaccumulation sur vers de terre ont montré que les HAP lourds (5 cycles et plus) étaient plus fortement accumulés que les légers (3 et 4 cycles)
A cokery soil polluted by PAHs was assessed for its toxicity and genotoxicity to soil and aquatic organisms. Total mean 16 PAH concentration was determined to 2634  241 mg/kg d. W. The heavy metals were in the range of the respective regional reference values. The effective concentration (EC) values based on concentration-response relationships were calculated. Toxicity of water extracts in chronic bioassays (algal growth and reproduction of C. Dubia) was high compared to acute toxicity (bacterial luminescence and daphnid viability). The Ames and Mutatox tests indicated mutagenicity of water extracts, while no response was found with the Umu test showing lower sensitivity. Germination of the tested plant species was not affected, contrary to plant growth. Fresh biomass was a more sensitive parameter than dry biomass. The results of terrestrial toxicity showed that toxic effect of contaminated soil was high, when survival and reproduction of collembola, reproduction of earthworm and survival of juvenile earthworm were measured. Different concentrations of the contaminated soil mixed with the artificial ISO or loamy natural soil were tested to determine influence of the control soil on toxicity. There was a significant trend that toxicity of contaminated soil was lower in the natural soil tested than in ISO, when reproduction of collembola and earthworm was studied. The transfer of PAHs from contaminated soil to biota (earthworm and plant) was inferior to 1, indicating no major problem in trophic chains. The earthworm bioaccumulation of high- molecular-weight PAHs with 5-6 aromatic rings was higher than the one of low-molecular-weight PAHs with 3-4 aromatic rings

La production du coke, utilisé en tant que combustible aux hauts-fourneaux, est assurée par un jeu de machines supervisées par un calculateur central et assistées par des machinistes pour la conduite (validation de fin de fonctionN), pour la maintenance (intervantion à la suite de l'apparition d'un défaut) ainsi que pour la sécurité des personnes et du matériel. L'analyse de l'existant met l'accent sur les dysfonctionnements qui bloquent le passage à une conduite entiérement automatique des machines. Le manque de fiabilité, la gestion des défauts et le systèmede positionnement ressortent comme étant les principaux points critiques à prendre en considération. Pour assurer une bonne fiabilité des équipements, une application d'aide à la maintenance a été développée et mise en service sur PC à la cokerie et concerne le calcul du temps de cycle et les mesures des taux de fiabilité par fonction. Un traitement analogue a été proposé pour le traitement des défauts. Les propositions d'amélioration de la gestion des défauts visent une simplification et une plus grande autonomie des automates machines. L'interface machine/four génere le lot majeur des défauts. Le positionnement, basé sur des mesures du génerateur d'impulsions (GI), est un point critique puisqu'il reste en boucle ouverte sur les 50 derniers centimètres à parcourir et est tributaire de tout patinage ou glissement de la roue. Les contraintes en temps (7 m en 30 s), l'inertie des machines (400 tonnes) et le nombre limité de capteurs au sol (1 par four) rendent difficile une démarche classique de bouclage. Une commande prédictive par auto-compensation de l'erreur permet d'améliorer le système de positionnement sans remise en caude de l'existant. Le suivi des écarts GI par rapport aux fours intermédiaires permet de quantifier les mesures passées des patinages et des glissements à partir desquelles on prédit l'erreur finale. Le modèle de prédiction est élaboré par une méthode de régression linéaire multivariable basée sur la méthode des moindres carrés, mise en oeuvre sous Excel, et est valide suivant des critères statistiques.

Les sols de cokerie sont très hétérogènes, composés de matériaux de construction et de diverses phases organiques telles que du coke, du charbon, du goudron de houille et du bitume routier, jouant un rôle majeur sur les propriétés de ces sols. Leur nature et leur état de dégradation vont influencer la mobilité des différents contaminants. Cette thèse porte sur l’étude du vieillissement d’un sol de cokerie et ses conséquences sur le devenir des polluants organiques et métalliques. Elle intègre des études réalisées à différentes échelles permettant de considérer différents degrés de complexité, par l’utilisation (i) de composés purs, de matériaux organiques isolés (charbon, goudron de houille)et de sols et (ii) de dispositifs intégrant progressivement les différents processus intervenant lors de l’atténuation naturelle : expériences d’oxydation et de biodégradation en laboratoire, dispositif simplifié permettant de suivre l’évolution naturelle de quelques grammes d’échantillon, parcelles lysimétriques du GISFI permettant un suivi à l’échelle du terrain. Deux schémas de dégradation ont été identifiés au cours des expériences en laboratoire : (i) l’oxydation conduit à un phénomène de condensation qui suggère une stabilisation du compartiment organique ; (ii) la biodégradation induit la formation de plus petites unités moléculaires et la libération de composés organiques présents dans la fraction organique insoluble. Si des tendances sont identifiées au cours des expériences d’atténuation naturelle, elles suggèrent plutôt que le processus majeur impliqué est la biodégradation. La sorption du cuivre est variable selon les constituants organiques considérés, et augmente significativement après les expériences d’altération
Coking plant soils are highly heterogeneous and are made of building materials and various organic constituents such as coke, coal, coal –tar and road asphalt. Those materials can strongly influence soil properties. Thus, the retention of the various contaminants will depend on the nature and the degradation of the soil organic constituents. This work deals with the ageing of a coking plant soil and its consequences on the fate of both organic and metallic pollutants. The multi-scale approach applied in this study allows to consider the different levels of complexity through the use of (i) pure compounds, isolated organic fraction of soils such as coal tar and coal and a soil with its mineral fraction, and (ii) experimental devices gradually integrating the processes involved in natural attenuation : laboratory oxidation and biodegradation experiments, simplified device allowing the study of few grams of samples exposed to natural attenuation, and the GISFI (French Scientific Interest Group – Industrial Wasteland) lysimeter plots allowing the study at field scale). Two major evolutions were evidenced: (i) the oxidation led to a condensation suggesting a stabilization process of the organic compartment; (ii) the biodegradation induce the formation of smaller molecular units and the release of organic compounds from the non extractable part of the organic matter. The trends identified during the natural attenuation experiments suggest that the biodegradation is the major process involved in our ageing experiments. The sorption of copper varied according to the different organic constituents that were tested but was clearly enhanced by the degradation of these constituents

2007/2008
Gli Idrocarburi Policiclici Aromatici (IPA), generati da processi di combustione o dispersi a seguito di sversamenti di petroli, risultano essere tra i microinquinanti organici più diffusi nell’ambiente. Essi sono spesso veicolati dal particolato atmosferico emesso da sorgenti in cui avvengono combustioni incomplete, quali motori presenti in autoveicoli o navi, sistemi di riscaldamento, impianti industriali. Le emissioni possono quindi contaminare il comparto atmosferico e le deposizioni secche o umide di particolato aerodisperso trasferiscono gli inquinanti a suoli, specchi d’acqua e indirettamente ad organismi viventi. Un ulteriore elemento di possibile criticità ambientale è associato ai residui solidi della combustione (es. ceneri pesanti), che possono contenere vari microinquinanti, tra cui gli idrocarburi policiclici aromatici, che hanno un potenziale tossico e cancerogeno, e che nel passato sono stati smaltiti sul territorio in discariche non sempre adeguatamente costruite e gestite. Lo studio sviluppato per la preparazione della presente tesi riguarda un ambito territoriale costiero, compreso tra Trieste e Muggia, in cui insiste – accanto a sorgenti comuni e diffuse quali il traffico auto-veicolare e portuale, impianti di riscaldamento e attività industriali quali un cementificio ed un inceneritore – una sorgente di idrocarburi policiclici aromatici di una certa rilevanza, costituita da una cokeria che è parte dell’impianto siderurgico a ciclo integrale situato nel rione di Servola, a Trieste. Il processo di distillazione del carbone, in particolare quando avviene in modo imperfetto ed in impianti di vecchia concezione, è una sorgente emissiva di contaminanti che non permette il rispetto degli standard ambientali nella sua prossimità, in particolare per quel che riguarda gli IPA e il particolato aerodisperso. Un significativo lavoro di caratterizzazione ambientale nella prossimità dell’impianto è stato eseguito dall’Agenzia Regionale per la Protezione dell’Ambiente del Friuli Venezia Giulia, che mette in atto campagne di monitoraggio istituzionale. Il presente lavoro, svolto nell’ambito del dottorato di ricerca, si è posto l’obiettivo di fornire informazioni complementari ed integrative al quadro ambientale disponibile, mettendo a punto procedure analitiche e di campionamento robuste che consentano di integrare i dati generati dalla ricerca universitaria con quelli prodotti dagli organi istituzionali di controllo ambientale. Una prima serie di campagne di indagini, svolta tra febbraio e luglio del 2006, ha consentito di determinare le concentrazioni di IPA nelle polveri fini, campionando per la prima volta il PM2.5 nel territorio giuliano, in un sito urbano a Trieste e in un sito posizionato lungo la costa, sottovento, rispetto ai venti prevalenti, alla zona industriale e portuale, che è potenziale sorgente di inquinanti organici persistenti. Le concentrazioni di PM2.5 risultano più critiche rispetto ai valori obiettivo di quanto lo sia il PM10 rispetto ai limiti vigenti. Sono stati determinati gli IPA nel PM2.5, in collaborazione con ARPA-FVG, evidenziando situazioni comparabili e non critiche rispetto al valore obiettivo per le concentrazione di benzo[a]pirene in atmosfera, con sporadici sforamenti rispetto alla media annuale di 1ng·m-3. È stata rilevata una marcata stagionalità nelle concentrazioni di IPA, con valori relativamente elevati in inverno e molto bassi in estate. La presenza di maggiori concentrazioni di ossidanti in atmosfera nel periodo estivo, attesa ad esempio per l’ozono, può giocare un ruolo, non ancora esplorato, nell’abbassare le concentrazioni di IPA nel particolato. È stata quindi messa a punto, presso i laboratori universitari, una procedura di trattamento dei campioni – basata sull’estrazione accelerata con solvente e su uno stadio di purificazione dell’estratto – e di analisi degli IPA in gas cromatografia accoppiata alla spettrometria di massa, che ha consentito di indagare, con modeste modifiche, matrici diverse provenienti da vari comparti ecologici. La validità della filiera analitica è stata verificata con la determinazione delle concentrazioni di IPA in matrici certificate (mitili liofilizzati SRM2977, sedimento di porto di acqua dolce BCR535, fango di impianto di trattamento BCR088) e con un'intercalibrazione con i laboratori ISPRA, ARPA-FVG ed INCA di Marghera per le analisi sul particolato atmosferico. Nella seconda serie di indagini si sono eseguiti monitoraggi nell’arco di otto mesi del 2007, campionando gli IPA aerodispersi totali (su filtro per le polveri totali sospese e su schiuma poliuretanica per la frazione più volatile), PM10 e PM2.5 in prossimità del perimetro dell’impianto siderurgico presente nel rione di Servola a Trieste ed in un sito relativamente remoto identificato nei pressi dell'Università. La caratterizzazione sperimentale della contaminazione da IPA aerodispersi ha permesso di identificare nella cokeria una sorgente di IPA molto rilevante. Si sono determinate concentrazioni totali di benzo[a]pirene (BaP) aerodisperso (nelle immediate vicinanze della Ferriera quasi sempre oltre il valore obiettivo medio annuale di 1ng·m-3) e di IPA totali, che risultano mediamente 100 volte superiori a quelli misurati presso l'Università (presso la quale non si sono mai registrati valori critici). Si è potuto mostrare anche come i profili di concentrazione degli IPA nei due siti (distanti quasi cinque chilometri) siano molto simili; contributi da altre sorgenti (es. emissioni tipicamente urbane come traffico veicolare e riscaldamento domestico/aziendale) non risultano marcatamente evidenti nel periodo di osservazione considerato. Anche a seguito dei risultati della seconda campagna, sono stati implementati degli adeguamenti per diminuire le emissioni incontrollate dall’impianto. Una validazione dei risultati sperimentali conseguiti durante tale campagna di monitoraggio è stata effettuata grazie ad un interconfronto in cui sono stati coinvolti i laboratori dell'Agenzia Nazionale per la Protezione dell’Ambiente e per i servizi Tecnici (ora ISPRA), dell'ARPA Friuli Venezia Giulia, del Consorzio Interuniversitario INCA di Marghera e dell’Unità di Ricerca in Chimica Ambientale dell’Università. I risultati dell'interconfronto hanno confermato la buona qualità delle metodologie di campionamento e analisi eseguite presso i nostri laboratori, dando un riscontro positivo sulle prestazioni sulle analisi di IPA nel particolato atmosferico, ma anche in fanghi e sedimenti. A seguito di ciò si sono iniziate caratterizzazioni di suoli – nell’ambito di sperimentazioni sul fitorimedio di siti contaminati da IPA – non riportate nella presente tesi. Un’ulteriore campagna di campionamenti ed analisi è stata svolta nel 2008, raccogliendo campioni di particolato atmosferico nell'area abitata di Servola, focalizzando l’attenzione sul contenuto di BaP nel particolato PM10, secondo una norma entrata in vigore con il Decreto Legislativo 152/07 pubblicato il 13 settembre 2007, che recepisce la direttiva europea 2004/107/CE e con il recepimento della norma tecnica EN 15549:2008. Ciò ha comportato una ritaratura delle metodiche di campionamento; in particolare sono stati scelti due siti di campionamento rappresentativi di aree abitate a Servola (“ex-Scuola” e via Pitacco) sono stati acquisiti campionatori di PM10 ad alto volume, integrando la rete di monitoraggio di ARPA-FVG con informazioni nel centro abitato prossimo all’impianto. I risultati di questa campagna di campionamento – conseguiti successivamente agli adeguamenti impiantistici della Ferriera – evidenziano come nelle aree prese in esame le situazioni di criticità riscontrate nelle precedenti campagne non vengano registrate; si verificano ancora sforamenti del valore limite di PM10 di 50μg·m-3, ma gli sforamenti al valore obiettivo di BaP di 1ng·m-3, sono molto più sporadici (1 sforamento su 43 giornate nel sito “ex-Scuola”, e 6 sforamenti su 47 in via Pitacco). Si è ritrovata una stagionalità nell'andamento delle concentrazioni di PM10 e di BaP nell'aria, con situazioni più critiche registrate nei mesi invernali. La presenza degli IPA è stata indagata anche nel comparto marino, vicino alla sorgente industriale di IPA aerodispersi. L'indagine sul bioaccumulo di IPA in Mytilus galloprovincialis nello specchio di mare prossimo all’impianto siderurgico e al terminal petroli – finalizzata ad evidenziare l’ingresso degli IPA nelle acque costiere ed in particolare la possibile contaminazione del biota a seguito di esposizioni di breve durata (cinque mesi) – ha fornito indicazioni sulle cinetiche di bioaccumulo caratteristiche delle diverse situazioni ambientali considerate, evidenziando una situazione di criticità nei pressi dell'area industriale ed una elevata biodisponibilità degli IPA disciolti in quello specchio d'acqua. La differenziazione delle analisi in diversi organi bersaglio (epatopancreas, branchie ed il resto del corpo) e l'integrazione dei livelli di contaminazione rilevati nei tessuti con il contenuto lipidico degli stessi ha mostrato una correlazione diretta fra livello di IPA accumulati e contenuto lipidico, confermando l'epatopancreas come organo bersaglio per l’accumulo di questa classe di inquinanti idrofobici. L'utilizzo di un organismo bioaccumulatore come Mytilus galloprovincialis si è rivelato essere un utile mezzo per la valutazione del grado di contaminazione di acque marine soggette a forte pressione antropica, anche in campagne di misura di durata relativamente breve. In conclusione, grazie all'attività svolta nel presente dottorato di ricerca è stato possibile approfondire vari aspetti sull'entità della contaminazione da idrocarburi policiclici aromatici sul territorio triestino, evidenziando alcune criticità in prossimità dell'impianto siderurgico di Servola. Misure di mitigazione delle emissioni in atmosfera, attuate durante l’arco di sviluppo del lavoro qui riportato, paiono contenere significativamente la criticità correlabile alla presenza di questi cancerogeni nell’aria ambiente. IPA bioaccumulabili sono tuttavia ancora significativamente presenti nelle acque costiere antistanti l’area industriale di Servola. Gli sviluppi del lavoro qui riportato sono orientati allo studio dei processi che modificano stagionalmente le concentrazioni degli IPA nel particolato, associabili all’azione di ossidanti atmosferici, quali l’ozono, sul PMX raccolto sui filtri e sull’impiego delle metodologie di estrazione ed analisi messe a punto per lo studio della contaminazione di campioni biologici, sedimenti e terreni. Si sono iniziati studi ad esempio nel contesto della valutazione di tecniche di fitorimedio per il recupero di aree contaminate da idrocarburi policiclici aromatici e ricerche in merito all'uso di gasteropodi terrestri e marini come bioaccumulatori di IPA, per la valutazione di potenziali rischi per l’ecosistema e la salute umana in siti inquinati.
XXI Ciclo
1974

Les procédés de cokéfaction ont entraîné l'incorporation dans les sols de goudrons de houille, phases non aqueuses liquides ou solides, contenant des HAP. L'objectif de ce travail était de comprendre la dynamique du terme source de HAP représenté par des particules de goudron et le mode de transport des HAP dans les sols contaminés depuis des dizaines d'années. Pour cela, des échantillons de sol et de goudron ont été collectés sur une friche industrielle et caractérisés par les techniques analytiques de la géochimie organique (GC-MS, micro spectroscopie IR). Le transfert des HAP en solution aqueuse à partir du goudron de houille a été étudié en colonne de laboratoire fonctionnant en boucle fermée; les résultats ont été interprétés par un modèle d'équilibre de partage entre phases et de cinétique de transfert. Le transport des HAP dans le sol contaminé a été étudié en colonne de laboratoire, les collectes ont été fractionnées (ultrafiltration et ultracentrifugation). On a montré que les HAP étaient transportés avec d'autres composés organiques à des concentrations souvent supérieures à leur solubilité dans l'eau: une part importante des HAP incluant les composés lourds est transportée par voie colloïdale. De plus, la comparaison des analyses organiques des phases solides et des collectes a mis en évidence des anàlogies de signature des HAP. Enfin, on a cherché à évaluer l'intérêt du traçage réactif pour la mesure de paramètres globaux (fraction de carbone organique foc et aire de l'interface eau/matière organique). Contrairement au phénol, le toluène a donné de bons résultats pour la mesure de foc, tandis que l' octylbenzènesulfonate de sodium n'a pas permis de mesurer l'aire interfaciale. En conclusion, ce travail a permis d'apporter des réponses précises sur la dynamique du terme source de HAP et le transport des HAP dans le sol par voie dissoute et colloïdale, base d'un modèle conceptuel et point de départ pour le passage à l'échelle pilote et de terrain
Coke production processes caused the incorporation of coal tars (NAPL or particle) into soils, these coal tars contain high amount of PAH. The aim of the present work was the investigation of the dynamics of the source term, nainely coal tar particles, as weIl as the transport of PAH through aged contaminated soils. Ln this goal, soil and coal tar samples were collected from brown field of an ancient coking plant. They were characterised by the analytical techniques of organic geochemistry (GC-MS, IR microspectroscopy). PAH transfer from coal tar particles into water was investigated by mean of closed loop laboratory column experiments. Results were interpreted by an equilibrium partitioning model and a mass transfer model. These models enabled us to compute a partitioning constant as weIl as effective diffusivities at various particle sizes and temperatures. PAH release and transport through contaminated soil was studied by laboratory column experiments, followed by phase separation of the collected fractions (ultrafiltration and ultracentrifugation). This method enabled us to show that PAH concentrations in the aqueous phase were most often higher than their aqueous solubility, and that the transport of a major fraction was facilitated by colloids and/or high molecular weight macromolecules. The com- parison between the data obtained by organic analysis showed analogy between the PAH spectra in the different phases. FinaIly, the potentiality of reactive tracers to measure global parameters (organic carbon fraction foc and sorbant organic phase/water interface are a) was tested. Conversely to phenol, toluene tracing enabled us to measure foc whereas sodium octylbenzenesulfonate did not allow the measurement of the interface area. As a conclusion, this research brought new results on the source term dynamics and PAH transport through contaminated soil from a former coking plant in aqueous and colloidal phases, that are the basis of a conceptual model and a first point to upscaling at the pilot and field scales

Afin de répondre aux besoins du marché de l’acier, le procédé de cokéfaction du charbon doit s’adapter. Cependant, changer les paramètres de cokéfaction du charbon, tels que la température du four, le temps de cuisson ou la composition de la pâte à coke enfournée, peut générer un endommagement prématuré de la maçonnerie des fours. En effet, la transformation du charbon en coke s’accompagne d’une poussée sur les parois du four fortement dépendantes d’un grand nombre de paramètres. Afin d’anticiper ce problème, un projet européen nommé « Swelling PRessure In a coke oven, Transmission on oven walls and COnsequences on wall » a été mis en place. Cette thèse s’inscrit dans ce programme et vise à déterminer la poussée maximale pouvant être admise par un piédroit de cokerie lors de la pyrolyse du charbon. Pour modéliser ces structures composées de plusieurs centaines de milliers de briques, le point de vue macroscopique est le plus approprié. La maçonnerie est remplacée par un matériau homogène équivalent dont le comportement varie en fonction de l’état d’endommagement de la maçonnerie, ramené localement à un état d’ouverture des joints de mortier. Afin de détecter ces ouvertures, un critère de type Mohr-Coulomb en contraintes est utilisé. Il repose sur la comparaison des limites à rupture d’un sandwich brique-Mortier déterminé expérimentalement à haute température avec les contraintes mésoscopiques issues de la simulation. Un protocole expérimental novateur a été développé pour caractériser la tenue en traction du sandwich brique / mortier / brique jusqu’à 1000°C. Les limites à rupture issues de cet essai de traction directe ont été comparées à celles obtenues par des essais de fendage réalisés à l’université de Leoben. Les résultats sont concordants et confirment l’importance de l’état de surface avant maçonnage. Selon l’état d’endommagement considéré, les contraintes mésoscopiques sont obtenues grâce à un tenseur de localisation ou grâce à une sous-Structuration. Cette étape de sous-Structuration consiste à simuler localement une cellule à l’échelle mésoscopique en lui appliquant le champ de déplacement macroscopique obtenu grâce à la simulation. L’outil numérique a été validé par confrontation avec un cas test de référence. Pour finir, l’outil numérique développé a été utilisé pour caractériser l’influence de différents paramètres tels que la prise en compte de la thermique, la mise en compression de la structure…. Enfin, la simulation de cuissons sur des piédroits complets (sains ou initialement endommagés) a été réalisée. L’importance de l’endommagement initial est clairement soulignée par les résultats. Enfin, un nouveau modèle, appelé « deux carneaux avec poutres», est proposé pour réduire le coût de calcul. Plus complet que le modèle « deux carneaux » utilisé au CPM, il donne accès à de très bons résultats pour un coût nettement moindre que celui du piédroit complet avec homogénéisation et sous-Structuration
To face coke and steel market requirements, the coking process has to be more flexible. Changing process parameters such as coking temperature, blend composition and cooking time can damaged coke oven battery heating wall. Indeed, the coking process generates a swelling pressure on wall which depends on a lot of parameters. To study this point, a European project named « Swelling PRessure In a coke oven, Transmission on oven walls and COnsequences on wall » has been set up. This work is a part of it and aims to determine the admissible pushing pressure for the coke oven heating walls to prevent crack formation. To model large masonries composed of numerous bricks, a mesoscopic point of view is more appropriate. Bricks and mortar are replaced by a Homogeneous Equivalent Material (HEM) whose behaviour depends on the joint state. In order to represent joint opening mechanism, a Mohr-Coulomb criterion in stress is used. This criterion compares the level of stress to the ultimate tensile or shear stress at mesoscopic scale. Ultimate stresses are obtained thanks to an experimental campaign using a new protocol developed at PRISME Laboratory. The brick-Mortar behaviour is experimentally characterised at high temperature (20°C to 1000°C). To validate the tensile test developed, a second experimental campaign using “wedge splitting tests” has been done at Leoben University. Results are similar and confirm the importance of the brick surface state. Depending on the initial damage of the structures, mesoscopic stresses are obtained by localization tensor or by sub-Modelling. The sub-Modelling step aims to simulate a local part of the masonry at the mesoscopic scale. This step aims to simulate with a mesoscopic point of view a local part of the global model. This numerical tool has been validated thanks to a literature test. Finally, the numerical tool has been used to characterise the influence of some parameters (thermal, force due to the cross tie rod,..). Next, the simulation of the whole coke oven heating wall has been performed (undamaged or initially damaged masonry). These FE simulations show the influence of initial damage on the final masonry damage. Finally, a two flues model with beams is proposed to take into account compression due to cross tie rod and to limit computational cost. It permits to obtain better results than the existing two flues model used at CPM with a lower cost compared to the whole coke oven heating wall model

Les stations d'épuration biologique de cokerie présentent fréquemment des dysfonctionnements dus à la variabilité des effluents. Celle-ci portant sur la composition et/ou la concentration peut rendre le système biologique instable et provoquer une baisse du rendement d'épuration. L'objectif de cette étude a essentiellement consisté à caractériser la cinétique de biodégradation du phénol et du Thio cyanate, qui constituent plus de 80% de la charge polluante de l'eau de cokerie. Des essais pilotes en discontinu ont permis de tester la validité des modèles de Monod et Haldane pour décrire la biodégradabilité de ces constituants. Les constantes obtenues dépendent des rapports entre les concentrations en substrat et en biomasse. Un modèle informatique de l'épuration biologique prenant en compte cette particularité a été élaboré puis validé par des essais réalisés en continu sur des installations pilotes de laboratoire. Quatre configurations de réacteurs de même volume global mais différant par leur nombre et la répartition de l'alimentation, ont été utilisés. La validation du nouveau modelé est effectuée par confrontation de ces prévisions avec les résultats expérimentaux. L'utilisation de ce modèle pour la réalisation d’opérations systématiques de simulation a permis de comparer les performances de multiples configurations de réacteurs élémentaires, tant sur le plan du rendement d'épuration que sur celui de la stabilité de fonctionnement (résistance à des points de pollution d'amplitudes et durée variables)

Les HAP font partie de la classe des polluants organiques persistants dans les sols. Dans le cadre de la réhabilitation d'anciennes friches industrielles, il est nécessaire de comprendre l'origine de leur forte rétention et de connaître leurs possibilités de re-mobilisation à l'eau. Pour cela, une évaluation du potentiel de re-mobilisation à l'eau de matrices industrielles polluées a été réalisée sur 6 mois à l'aide de réacteurs fermés dont la solution est renouvelée mensuellement. Des expériences d'adsorption/désorption du 14C-fluoranthène sur ces mêmes matrices ainsi que sur une terre agricole ont confirmé que le fluoranthène s'adsorbe par interaction hydrophobe. L'affinité exceptionnelle des HAP pour les matrices présentant une pollution amassée est associée à leur re-mobilisation limitée par le faible contact de l'eau avec les surfaces de ces matrices hydrophobes. Notre étude met également en évidence la désorption plus lente de HAP "natifs" par rapport à des HAP ajoutés récemment, traduisant une modification du comportement de HAP au cours du temps. Afin de comprendre les mécanismes impliqués dans ce "vieillissement" au sein de terres industrielles, une expérience d'incubation de petites colonnes de sol, contaminées par du 14C-fluoranthène, a été conduite sur 6 mois. Dans les matrices à pollution amassée, le fluoranthène reste sous une forme extractible. Dans les matrices présentant une pollution moins importante et non amassée, le devenir des résidus du 14C-fluoranthène est contrôlé par l'activité de la microflore. Il est montré en particulier que les produits de dégradation sont en effet plus mobiles et peuvent pénétrer dans la porosité et y être séquestrés.

L'optimisation du fonctionnement d'une installation d'épuration d'eaux usées industrielles par boues activées, nécessite une bonne connaissance des processus biologiques mis en jeu. Le problème essentiel du traitement d'eaux usées industrielles est celui de la toxicité de l'effluent à traiter. Nous proposons dans ce travail, d'étudier l'influence de l'hydrodynamique du bassin d'aération sur les performances d'épuration de l'eau de cokerie. Les deux principaux polluants sont le phénol et le thiocyanate. La comparaison du fonctionnement de 2 aérateurs différents (1 RPA de 20 litres et une cascade de 5 RPA de 4 litres chacun, montre la très forte influence de la distribution des temps de séjour de la phase aqueuse sur la dégradation des polluants. Du fait du caractère toxique de l'effluent, la plus grande stabilité de fonctionnement est obtenue dans le RPA de 20 litres. Aussi, pour ce type d'effluent toxique, le RPA semble le plus apte à supporter la variabilité de la qualité de l'eau à traiter. Néanmoins, les mesures effectuées dans la cascade de 5 RPA mettent en évidence la dégradation séquentielle des phénols et du thiocyanate. L'ensemble des résultats expérimentaux a permis la détermination des paramètres cinétiques. Enfin, un nouveau type de bioréacteur, cascade de RPA a circulation à contre-courant, dit « gradostat », est étudié. Il permet notamment d'obtenir en continu une biomasse adaptée à la dégradation d'effluents toxiques ou difficilement biodégradables
The optimisation of the performance of the industrial waste water treatment by activated sludge, requires a good knowledge of the biological processes used. The main problem of industrial waste water treatment is the influent component toxicity. The objective of this work is to present a study about, influence of aeration basin hydrodynamic on the filtering performances of coke oven waste water treatment. The two principal pollutants are phenol and thiocyanate. The comparison of the fonctionning of two different aeration basins (1 CSTR of 20 litres and 5 CSTR’s of 4 litres each in series), shows the great influence of water Residence Time Distribution on pollutant degradation. Due to the toxic character of the influent, the higher stability is obtained in single CSTR, where the toxicity is quickly diluted. So, for this kind of industrial influent, a single CSTR, for the aeration basin, is the more capable waste water treatment plant to have a good removal pollution efficiency, and, particularly to absorb the variations of pollutant concentrations in the influent. Howewer, the study in the 5 CSTR’s in series shows that, the main pollutants (phenol, and, thiocyanate) are sequentially degraded, with an inhibition of thiocyanate degradation by residual phenol concentration. All the experimental results, have permitted to determinate kinetic parameters. At last, a new type of bio-reactor, CSTR’s in series with counter-lfow feeding, is studied. It allows, to obtained in continuous, an adapted biomass for toxic influent biodegration

As throughput is increased and cycle times are reduced for delayed cokers, many owners are experiencing an increased occurrence of repairs and drum failures. Typically, other equipment in the facilities are upgraded while the coker unit is left unchanged and is expected to perform under more severe cyclic conditions. The operators are required to keep increasing the throughput and decrease the cycle time to meet targeted production. Most Coke drum failures are due to the high cyclic thermal stresses. Cyclic thermal stresses along with their increased occurrence lead to premature failures and cracking. It can be shown that by adding a 3rd drum to a 2 drum unit, the drum life can be extended by several fold, possibly eliminate the need to replace the coke drums and at the same time increase throughput.

On November 1, 1998 the Petropower Energia Limitada Project, located adjacent to Petrox’s 84,000 barrel per day (bpd) refinery in Talcahuano, Chile, entered into Commercial Operations. In addition to being the first public/private industrial partnership in Chile, it also was the first to combine petroleum coking technology with cogeneration technology in a single project financing. The project consists of a Delayed Coker Facility, which includes a 12,000 bpd Delayed Coker Unit and a 7,000 bpd Hydrotreating Unit, and a 74 MW (nominal, gross) Cogeneration Facility. The coke produced fuels a Foster Wheeler Circulating Fluidized Bed Boiler (CFB), and the energy produced provides electric power for the Petrox Refinery, the Delayed Coker Facility, and third parties, and high pressure steam for the refinery. The Cogeneration Facility, which consumes 24.8 Tonnes Per Hour of green coke, produces high-pressure steam, demineralized water and electricity for export to the refinery. The cogeneration unit also exports electricity, boiler feedwater and plant air to the Delayed Coker Facility. This leaves approximately 42 MW which is being exported to local third parties and the national grid. Environmentally, the overall project has resulted in a decrease in sulfur dioxide and particulate emissions from the refinery because of emission controls in the CFB, and elimination of burning fuel oil in the old utility system. Overall, the Delayed Coker Facility has permitted Petrox to refine heavier, less costly crudes, and the Hydrotreater Unit produces cleaner gasoline and diesel products. Petrox obtained these benefits without the expenditure of capital on the project, other than a small equity investment. The Cogeneration Facility has, and will continue to provide a long term, environmentally friendly solution to disposal of the high sulfur content coke produced by the coker, and maximizes its value as a high BTU (kilojoule - kJ) fuel for the Cogeneration Facility. The Cogeneration Facility has supplied all the refinery’s utility needs reliably and consistent with its expansion plans. After briefly describing the overall project, this paper places emphasis on the cogeneration plant with a focus on the operational experiences, including fouling, and the reliability improvements undertaken during the plant’s last three years of commercial operation. In addition, O&M costs and an overview of project economics are discussed.

Coke drums are pressure vessels that are used in oil sands and conventional refinery processing industries for the thermal cracking of reduced bitumen to recover additional, saleable gas and liquid product streams. The drums are constructed to the requirements of ASME VIII Division 1 although they are in a low cycle thermal-mechanical service environment. Recent practice has been to introduce design by analysis considerations from ASME VIII Division 2 even though service temperatures of the actual equipment exceed the design limits of the Code. In this paper, simplified elastic-plastic analysis models are developed for assessment of the stress and strain levels in coke drums during specific operational phases. One model is applied for determination of the local stress caused by differences in the coefficients of thermal expansion between the clad liner and base materials. Because clad construction is used throughout the vessel, the impact is extensive. Consideration is given to the general stresses induced by the cyclical, progressive dilation and contraction action of the drum shell caused by axial thermal gradients. Another model estimates hot and cold spot formation and the development of localized stress / strain distributions in coke drums. The resulting thermal stresses include the local stress from suppression of differential expansion between clad and base material, thermal bending stresses and local thermal stresses from hot and cold spot formation. It is found that the evaluation of these loads on drum cracking aligns with industry survey results. Better understanding of these loads has impact on materials selection and fabrication procedures for new drums and repair of existing drums. Operational considerations can also be identified to help improve drum reliability.

A stated goal of governments in addressing climate warming and to transition to a low carbon future by the end of this century is to increase the proportion of energy supplied by alternative sources. For the hydrocarbon processing industry, the question of stranded assets will become significant as these alternative energy sources become more prevalent. Existing equipment will need to operate to the end of its useful life and new equipment may need to be avoided. In particular, coker drums are very expensive investments due to their size, materials and number required in the delayed coker unit of a processing facility. Because of the severe service environment in which coke drums operate, the service life of a drum is not well established. Long term reliability of coker drums is impacted by thermo-mechanical damage mechanisms associated with self constraint of the drum shell and skirt during the formation of hot and cold temperature spots and patches. By assessing the imposed thermomechanical strains, a more precise determination of drum fatigue may be made, allowing better estimation of service life. This service life may be estimated for newly fabricated drums and those drums with shell damage, such as bulging. Service life determination is of practical importance for operators since it provides a more realistic estimate of operational life as compared to the normally referenced Code design life. An accurate estimation of drum service life has not been available in the industry to date due to a number of deficiencies and conservatisms in the current calculation practices. Insight into the causal damage mechanism provides opportunities in identifying alternatives in design, material selection, fabrication, inspection, and maintenance for operating this equipment to a practical and optimal target service life.

Delayed coker drums are unique in hydrocarbon processing facilities in that estimating their true design and service life has been problematic. Generally, pressure containing equipment in these facilities is designed using the notion of design life based on required pressure thickness and corrosion allowance considerations. Hence, pressure containing equipment is routinely monitored by facility inspectors for wall thickness. Although many analysts have ascribed coke drum failure to “thermal stress cycling”, the difficulty posed by the operation of coke drums results in an inability to measure or calculate the magnitude of the thermo-mechanical “stresses” and the actual number of significant exposures, that is, cycles causing fatigue damage. As well, the use of Code construction practices has been generally misapplied, for this specific equipment, as the practices are intended to define a safe design life rather than a service life. Indirect measures of service life based on shell bulge severity have fallen from favor by being ineffective. A trend to use a strain index method is somewhat more appealing but is based on static load and monotonic material property considerations rather than those properties indicative of thermal cyclic operation. Recent work has shown that thermo-mechanical strain cycling can be characterized quantitatively and used to determine a cyclic service life for both undamaged and damaged coke drums. This paper discusses some of the engineering specifics to generate a high probability estimate of coke drum fatigue service life for a new drum, a damaged-stable drum, drums with weld overlay and for drums exhibiting incremental damage.

Delayed unit coker drums operate in a severe service environment that precludes long term reliability due to excessive shell bulging and cracking of shell joint and shell to skirt welds. Thermal fatigue is recognized as the leading damage mechanism and past work has provided an idealized description of the thermo-mechanical mechanism via local hot and cold spot formation to quantify a lower bound life estimate for shell weld failure. The present work extends this idealized thermo-mechanical damage model by evaluating actual field data to determine a potential upper bound life estimate. This assessment also provides insight into practical techniques for equipment operators to identify design and operational opportunities to extend the service life of coke drums for their specific service environments. A modern trend of specifying higher chromium and molybdenum alloy content for drum shell material in order to improve low cycle fatigue strength is seen to be problematic; rather, the use of lower alloy materials that are generally described as fatigue tough materials are better suited for the high strain-low cycle fatigue service environment of coke drums. Materials such as SA 204 C (C – ½ Mo) and SA 302 B (C – Mn – ½ Mo) or SA 302 C (C – Mn – ½ Mo – ½ Ni) are shown to be better candidates for construction in lieu of low chromium alloy steel materials such as SA 387 grades P11 (1¼ Cr – ½ Mo), P12 (1 Cr – ½ Mo), P22 (2¼ Cr – 1 Mo) and P21 (3 Cr – 1 Mo).