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Littérature scientifique sur le sujet « Dioxins formation »

Auteur : Grafiati

Publié le 9 mars 2023

Mis à jour le 10 mars 2023

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Articles de revues sur le sujet "Dioxins formation"

He, Hao, Xuanhao Guo, Lizheng Jin, Yaqi Peng, Minghui Tang et Shengyong Lu. « The Effect of Adjusting Sinter Raw Mix on Dioxins from Iron Ore Co-Sintering with Municipal Solid Waste Incineration Fly Ash ». Energies 15, n^o 3 (3 février 2022) : 1136. http://dx.doi.org/10.3390/en15031136.

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The inhibition effect of calcined lime (CaO) and limestone (CaCO3) on the formation of dioxins during iron ore co-sintering with fly ash was investigated in a sinter pot in the present work. Experimental results indicated that international total toxicity equivalent concentration of dioxins decreased from 1.4335 to 0.2922, 0.1048, 0.4562, and 0.3098 ng I-TEQ Nm−3 under four different experimental conditions. It can be concluded that 5 wt.% calcined lime with 3 wt.% limestone is the optimal addition to reduce the concentration of dioxins in flue gas, with 92.70% inhibition efficiency. Effects on dioxin distribution was also analyzed. The distribution proportion of low-chlorinated dioxins was found to increase, while that of high-chlorinated dioxins decreased, except for octachlorianted dibenzo-p-dioxins (OCDD). The reason is that the consumption of HCl not only inhibits the de novo synthesis, but also dramatically promotes the condensation and dechlorination to produce more tetrachlorianted dibenzo-p-dioxins and octachlorianted dibenzo-p-dioxins through precursors. Finally, condensation, dichlorination, and inhibition mechanisms of dioxins during co-sintering with municipal solid waste incineration (MSWI) fly ash are proposed.

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Long, Hong Ming, Jia Xin Li, Ping Wang et Ru Fei Wei. « Synthesis Pathway of Dioxins in Iron Ore Sintering Process ». Advanced Materials Research 194-196 (février 2011) : 71–74. http://dx.doi.org/10.4028/www.scientific.net/amr.194-196.71.

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Dioxins are a kind of extremely toxic and Persistent Organic Pollutants (POPs). Sintering process has become one of the most dominant unintentional discharge sources. The dioxins synthesis pathway and mechanism being described, related research indicate that: in the low temperature sector (200-500ºС), chlorobenzene and chlorphenol are the representation precursors of dioxin’s precursor catalytic reaction, the dioxins formed in this temperature sector cased by the “de novo” under catalyst (like Cu2+) on the surface of smoke particles; high-temperature gas phase reaction mechanism of dioxins satisfied the first-order kinetic model, the formation of gas related with suitable precursors, it is the result of chlorinated precursors’ pyrolytic rearrangement like chlorobenzene and chlorophenol in the temperature sector 500-800ºС in the gas.

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KAWABATA, Hirotoshi, et Tateo USUI. « Technologies on Suppression of Dioxins Formation ». Journal of High Temperature Society 34, n^o 1 (2008) : 3–8. http://dx.doi.org/10.7791/jhts.34.3.

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Ma, Xiao Cheng, Xian Ping Zeng, Jian Tao Liu, Kun Kun You et Jian Xing Ren. « Technology to Control PCDD/Fs from MSW Incineration Processes ». Advanced Materials Research 610-613 (décembre 2012) : 2621–26. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.2621.

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At present the dioxin problem caused by MSW(Municipal solid waste) incineration has become the point problem of the development of application. According to the formation mechanisms of dioxins in the process of MSW incineration prevention measure may divide into the combustion, the combustion before and burn the latter three broad headings prevention measure which produced the PCDD/Fs after burning area mainly include in the haze, the flying ash the PCDD/Fs removing and prevents some measures which PCDD/Fs produces. Finally this paper proposed several measures in control and purification dioxins technology.

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Furue, Masutaka, et Gaku Tsuji. « Chloracne and Hyperpigmentation Caused by Exposure to Hazardous Aryl Hydrocarbon Receptor Ligands ». International Journal of Environmental Research and Public Health 16, n^o 23 (3 décembre 2019) : 4864. http://dx.doi.org/10.3390/ijerph16234864.

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Dioxins and dioxin-like compounds are environmental pollutants that are hazardous to human skin. They can be present in contaminated soil, water, and air particles (such as ambient PM2.5). Exposure to a high concentration of dioxins induces chloracne and hyperpigmentation. These chemicals exert their toxic effects by activating the aryl hydrocarbon receptor (AHR) which is abundantly expressed in skin cells, such as keratinocytes, sebocytes, and melanocytes. Ligation of AHR by dioxins induces exaggerated acceleration of epidermal terminal differentiation (keratinization) and converts sebocytes toward keratinocyte differentiation, which results in chloracne formation. AHR activation potently upregulates melanogenesis in melanocytes by upregulating the expression of melanogenic enzymes, which results in hyperpigmentation. Because AHR-mediated oxidative stress contributes to these hazardous effects, antioxidative agents may be potentially therapeutic for chloracne and hyperpigmentation.

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Barysheva, Olga, Renat Sadykov, Yuri Khabibullin et Elizaveta Zheltukhina. « Forecasting of an output of eco toxicants at thermal decomposition of chemical fuel ». E3S Web of Conferences 140 (2019) : 08002. http://dx.doi.org/10.1051/e3sconf/201914008002.

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Combustion of high-energy chemical fuels containing chlorine in the element structure can lead to formation in the particles of smoke of super eco toxicants—the polychlorinated dioxins and furans. The numerical experiment conducted was based on solution of the equations of chemical kinetics. The computational and theoretical researches directed to the solution of a problem of determination of parameters of combustion products of chemical fuels taking into account formation of harbingers of the polychlorinated dioxins were executed. The main data on the accepted method of determination of disequilibrium structures of products of burning the chlorine-containing chemical fuels were represented. Based on the analysis of references about mechanisms and speeds of chemical reactions of transformations of chlorine-containing connections, the kinetic model of formation of predecessors of dioxins is constructed. The carried-out calculations showed (assuming chemical balance) that process of formation of dioxins is significantly disequilibrious. The results of kinetic researches on emission of harbingers of dioxins showed the nature of the influence of different components of combustion products of chemical fuels on time for the different levels of temperatures.

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Stanmore, B. R. « The formation of dioxins in combustion systems ». Combustion and Flame 136, n^o 3 (février 2004) : 398–427. http://dx.doi.org/10.1016/j.combustflame.2003.11.004.

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Wielgosiński, Grzegorz. « The Possibilities of Reduction of Polychlorinated Dibenzo-P-Dioxins and Polychlorinated Dibenzofurans Emission ». International Journal of Chemical Engineering 2010 (2010) : 1–11. http://dx.doi.org/10.1155/2010/392175.

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In the study the most important and known polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) emission sources are presented and known methods of reduction of dioxin emission to the atmosphere are discussed in detail. It is indicated that the most relevant emission source is a combustion process. The mechanism of dioxin formation in thermal processes is presented in brief. The author characterized primary methods of reduction of PCDDs/PCDFs emission encompassing the interference into the combustion process to minimize their formation and discussed known secondary methods aimed at their removal from the stream of waste gases. It was attempted to make a critical assessment of PCDD/Fs reduction methods described in literature.

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Mohamed, Khairulmazidah, Mohamed Isa Abdul Majid, Yin-Hui Leong et Xiaodong Li. « Dioxins in peat and its formation : An overview ». Cogent Environmental Science 6, n^o 1 (1 janvier 2020) : 1864870. http://dx.doi.org/10.1080/23311843.2020.1864870.

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KATO, Yoichi, et Katsuhiko IIDA. « Formation of Dioxins on Metals during Soldering Process ». Journal of Environmental Chemistry 15, n^o 3 (2005) : 575–83. http://dx.doi.org/10.5985/jec.15.575.

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Thèses sur le sujet "Dioxins formation"

Jansson, Stina. « Thermal formation and chlorination of dioxins and dioxin-like compounds ». Doctoral thesis, Umeå universitet, Kemi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1881.

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This thesis contributes to an increased understanding of the formation of dioxins and dioxin-like compounds in combustion processes. Although emissions to air from waste incineration facilities have been greatly reduced by the use of efficient air pollution control measures, the resulting residues (ashes and filters) are highly toxic and are classified as hazardous waste. The main objective of the work underlying this thesis was to elucidate the formation and chlorination pathways of dioxins and dioxin-like compounds in waste combustion flue gases in the temperature range 640-200°C in a representative, well-controlled laboratory-scale reactor using artificial municipal solid waste. This could contribute to the reduction of harmful emissions to air and also reduce the toxicity of waste incineration residues, thus reducing or even eliminating the need for costly and potentially hazardous after-treatment. A comparison of four different quenching profiles showed that the formation of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) was rapid and mainly occurred in the 640-400°C temperature region, with high dependency on sufficient residence time within a specific temperature region. Prolonged residence time at high temperatures (450/460°C) reduced the PCDD yields, even at lower temperatures along the post-combustion zone. PCDD, PCDF and PCN (polychlorinated naphthalene) isomer distribution patterns indicated contributions from chlorophenol condensation as well as chlorination reactions for all three classes of compounds. The formation of PCDDs was largely influenced by chlorophenol condensation and to some extent by chlorination reactions. For the PCDFs, chlorine substitution adjacent to the oxygen bridges was unfavoured, as demonstrated by the notably lower abundance of 1,9-substituted congeners. This was supported by bidirectional orthogonal partial least squares (O2PLS) modelling. The variable with the greatest influence on the distribution of PCDD congeners was the relative free energy (RΔGf). The O2PLS models displayed distinct clusters, dividing most of the homologues into two or three sub-groups of congeners which seemed to correspond to the probability of origination from chlorophenol condensation. The effects of injection of aromatic structures into the flue gas differed for each class of compounds. Injection of naphthalene increased the formation of monochlorinated naphthalene but the remaining homologues appeared to be unaffected. This was probably due to insufficient residence time at temperatures necessary for further chlorination. Injected dibenzo-p-dioxin was decomposed, chlorinated and re-condensated into PCDDs and PCDFs, whereas injection of dibenzofuran and fluorene reduced the PCDD levels in the flue gas.
Denna avhandling fokuserar på olika aspekter som kan bidra till en ökad förståelse av bildning av dioxiner och dioxin-lika föreningar i förbränningsprocesser. Även om utsläppen till luft från sopförbränningsanläggningar har minskat kraftigt tack vare effektiva rökgasreningsmetoder, så återstår problemet med mycket giftiga rökgasreningsprodukter (askor och filter), vilka klassificeras som farligt avfall. Det huvudsakliga syftet med arbetet bakom denna avhandling var att klarlägga bildnings- och kloreringsvägarna för dioxiner och dioxin-lika föreningar i temperaturintervallet 640-200°C i rökgaser från sopförbränning. Detta kan möjliggöra lösningar för ytterligare emissionsminskningar och en avgiftning av biprodukterna från avfallsförbränning, vilket minskar eller till och med eliminerar behovet av kostsam och riskfylld efterbehandling. Realistiska och välkontrollerade försök har utförts i en lab-skalereaktor där en artificiell hushållssopa har förbränts. En jämförelse av fyra olika temperatur- och uppehållstidsprofiler visade att bildning av polyklorerade dibenso-p-dioxiner (PCDD) och dibensofuraner (PCDF) sker snabbt och huvudsakligen inom temperaturintervallet 640-400°C. Bildningen var starkt beroende av en tillräckligt lång uppehållstid inom ett visst temperaturområde. En förlängd uppehållstid vid höga temperaturer (>450°C) resulterade i minskade halter av PCDD, vilka förhöll sig låga även senare i efterförbränningszonen. Isomermönstren av PCDD, PCDF och PCN (polyklorerade naftalener) visade alla tecken på att härröra från både klorfenolkondensation och kloreringsreaktioner. PCDD-mönstret visade tydliga indikationer på bildning från klorfenoler, och till mindre grad bildning via klorering. För PCDF var klorsubstitution i positioner angränsande till syrebryggan missgynnad, vilket bekräftades av multivariat modellering (O2PLS). Den variabel som starkast påverkade bildningen av PCDD var relativa fria energin (RΔGf). Modellerna visade på en distinkt gruppering av PCDD- och PCDF-kongenerna i två eller tre grupper för varje kloreringsgrad, och föreslås vara relaterad till sannolikheten för respektive kongen att bildas via klorfenolkondensation. Injektion av aromatiska kolstrukturer i rökgaskanalen gav upphov till skilda effekter. Injektion av naftalen ökade bildningen av monoklorerad naftalen medan resterande homologer inte verkade påverkas, sannolikt på grund av för kort uppehållstid för ytterligare klorering. Dibenso-p-dioxin spjälkades sannolikt till fenoliska fragment som klorerades och sedan återkondenserades till PCDD och PCDF, medan dibensofuran och fluoren kraftigt reducerade PCDD-koncentrationerna.

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Gao, Qiuju. « Dioxins and dioxin-like compounds in thermochemical conversion of biomass : formation, distribution and fingerprints ». Doctoral thesis, Umeå universitet, Kemiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-118861.

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In the transition to a sustainable energy supply there is an increasing need to use biomass for replacement of fossil fuel. A key challenge is to utilize biomass conversion technologies in an environmentally sound manner. Important aspects are to minimize potential formation of persistent organic pollutants (POPs) such as dioxins and dioxin-like compounds. This thesis involves studies of formation characteristics of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and naphthalenes (PCNs) in microwave-assisted pyrolysis (MAP) and torrefaction using biomass as feedstock. The research focuses are on their levels, distributions, fingerprints (homologue profiles and isomer patterns) and the underlying formation pathways. The study also included efforts to optimize methods for extracting chlorinated aromatic compounds from thermally treated biomass. The overall objective was to contribute better understanding on the formation of dioxins and dioxin-like compounds in low temperature thermal processes. The main findings include the following: Pressurized liquid extraction (PLE) is applicable for simultaneous extraction of PCDDs, PCDFs, PCNs, polychlorinated phenols and benzenes from thermally treated wood. The choice of solvent for PLE is critical, and the extraction efficiency depends on the degrees of biomass carbonization. In MAP experiments PCDDs, PCDFs and PCNs were predominantly found in pyrolysis oils, while in torrefaction experiments they were mainly retained in solid chars with minor fractions in volatiles. In both cases, highly chlorinated congeners with low volatility tended to retain on particles whereas the less chlorinated congeners tended to volatize into the gas phase. Isomer patterns of PCDDs, PCDFs and PCNs generated in MAP were more selective than those reported in combustion processes. The presence of isomers with low thermodynamic stability suggests that the pathway of POPs formation in MAP may be governed not only by thermodynamic stabilities but also by kinetic factors. Formation of PCDDs, PCDFs and PCNs depends not only on the chlorine contents in biomass but also the presence of metal catalysts and organic/metal-based preservatives. Overall, the results provide information on the formation characteristics of PCDDs, PCDFs and PCNs in MAP and torrefaction. The obtained knowledge is useful regarding management and utilization of thermally treated biomass with minimum environmental impact.

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Ryu, Jae-Yong. « Dioxin formation on copper (II) chloride from chlorinated phenol, dibenzo-p-dioxin and dibenzofuran precursors ». Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/19050.

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Akki, Umesh. « Gas phase formation pathways and mechanisms of polychlorinated dibenzo-p-dioxins and dibenzofurans ». Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/23157.

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JAMSHAID, ASHIQ MUHAMMAD. « Influence of alternative fuels on the formation of dioxins in a cement production plant ». Thesis, Umeå universitet, Kemiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-89026.

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Arnoldsson, Kristina. « Polybrominated dibenzo-p-dioxins : Natural formation mechanisms and biota retention, maternal transfer, and effects ». Doctoral thesis, Umeå universitet, Kemiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-50887.

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Polybrominated dibenzo-p-dioxins (PBDD) and dibenzofurans (PBDF) are a group of compounds of emerging interest as potential environmental stressors. Their structures as well as toxic responses are similar to the highly characterized toxicants polychlorinated dibenzo-p-dioxins. High levels of PBDDs have been found in algae, shellfish, and fish, also from remote areas in theBaltic Sea. This thesis presents studies on PBDD behavior in fish and offspring, and natural formation of PBDDs from naturally abundant phenolic precursors. The uptake, elimination, and maternal transfer of mono- to tetraBDD/Fs were investigated in an exposure study reported in Paper I. The effects of PBDDs in fish were examined in a dose-response study (Paper II). It was shown that fish can assimilate PBDD/Fs from their feed, although non-laterally substituted congeners were rapidly eliminated. Laterally substituted congeners were retained as was congeners without vicinal hydrogens to some extent. PBDD/Fs were transferred to eggs, and congeners that were rapidly eliminated in fish showed a higher transfer ratio to eggs. Exposure to the laterally substituted 2,3,7,8-TeBDD had significant effects on the health, gene expression and several reproduction end-points of zebrafish, even at the lowest dose applied. The geographical and temporal variations of PBDD in biota samples from the Baltic Seasuggest biogenic rather than anthropogenic origin. In Paper III, bromoperoxidase-mediated coupling of 2,4,6-tribromophenol yielded several PBDD congeners, some formed after rearrangement. The overall yield was low, but significantly higher at low temperature, and the product profile obtained was similar to congener profiles found in biota from the Swedish West Coast. In Paper IV, photochemically induced cyclization of hydroxylated polybrominated diphenyl ethers under natural conditions produced PBDDs at percentage yield. Rearranged products were not detected, and some abundant congeners do not seem to be formed this way. However, the product profile obtained was similar to congener profiles found in biota from the Baltic Proper. Since the PBDD congeners found in biota have a high turn-over in fish, the exposure must be high and continuous to yield the PBDD levels measured in wild fish. Thus, PBDDs must presumably be formed by common precursors in general processes, such as via enzymatic oxidations, UV-initiated reactions or a combination of both. The presented pathways for formation of PBDDs are both likely sensitive to changes in climatic conditions.

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PICCINELLI, ELSA. « Environmental impact of industrial plants combustion processes : kinetic and formation/destruction mechanisms of PolichlorinatedDibenzo-p-Dioxins and PolichlorinatedDibenzoFurans ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2009. http://hdl.handle.net/10281/10060.

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The aim of the project was to study the mechanism of formation and degradation of PolyChlorinatedDibenzo-p-Dioxins (PCDDs) and PolyChlorinatedDibenzoFurans (PCDFs) in combustion processes. Today the challenge is to demonstrate that the conclusion based on laboratory scale experiments and the models coming from the results are useful tools to estimate emissions and to prevent or reduce PCDD/F (sum of PCDDs and PCDFs) formation in the flue gas cleaning system of plants. Following this, the study was developed at two different scales: Laboratory scale. The native carbon oxidation and PCDD/F formation were simultaneously studied at different temperatures (230-350 °C) and times (0-1440 min) in order to establish a direct correlation between the disappearance of the reagents and the formation of the products. The kinetic runs were conducted in a experimental set up where conditions were chosen to gain information on the role of fly ash deposits in cold zone of the plant in PCCD/F formation reaction Real plant scale. An extensive experimental study of a secondary aluminium casting plant flue gas cleaning system was performed. In particular, on the strength of the knowledge obtained by laboratory studies and the results of the samplings, the best strategies to prevent PCDD/F formation were identify and Air Pollution Control Device (APCD) performance was improved.

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Saeed, Anam. « Studies on the Decomposition of Selected Brominated Flame Retardants (BFRs) and Formation of Polybrominated Dibenzo-p-dioxins and Dibenzofurans (PBDD/Fs) and Mixed Halogenated Dibenzo-p-dioxins and Dibenzofurans (PXDD/Fs) ». Thesis, Saeed, Anam (2016) Studies on the Decomposition of Selected Brominated Flame Retardants (BFRs) and Formation of Polybrominated Dibenzo-p-dioxins and Dibenzofurans (PBDD/Fs) and Mixed Halogenated Dibenzo-p-dioxins and Dibenzofurans (PXDD/Fs). PhD thesis, Murdoch University, 2016. https://researchrepository.murdoch.edu.au/id/eprint/35843/.

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Brominated flame retardants (BFRs) are bromine-bearing hydrocarbons added or applied to materials to increase their fire resistance. As thermal treatment or recycling activities are common disposal methods for BFR-laden objects, it is essential to determine the precise decomposition chemistry of BFRs at elevated temperatures, and their transformation pathways into hazardous pollutants. Sunlight can trigger the photodecomposition of BFRs, either during the life cycle of treated objects, or when emitted to the environment after disposal. Therefore, knowledge of the geometric and electronic structures of BFRs is of chief importance when tracking their fate in the ambient environment. Although BFR decomposition mainly occurs in a condensed phase, gas phase reactions also contribute significantly to their overall decay and subsequent fragmentation into brominated pollutants. Thermal degradation of BFRs often proceeds in the presence of bromine atoms which inhibit complete combustion. Therefore, under thermal conditions such as smouldering, municipal waste incineration, pyrolysis, thermal recycling, uncontrolled burning and fires, BFRs degrade to form brominated products of incomplete combustion (BPICs). Thermal degradation of BFRs produces potent precursors to polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs). Co-combustion of BFR-containing objects with a chlorine source (e.g., polyvinyl chlorides) results in the emission of significant concentrations of mixed halogenated dibenzo-p-dioxins and dibenzofurans (i.e., PXDD/Fs; X = Br, Cl). In this thesis, we investigated the thermochemical parameters of bromochlorophenols (BCPhs) and the photodecomposition properties of major BFRs and their derived brominated phenols (BPhs). We scrutinised the formation of brominated and non-brominated products that evolved during the thermal decomposition of major BFR i.e., tetrabromobisphenol A (TBBA), through experimental measurements coupled with accurate quantum chemical calculations. We acquired thermo-kinetic parameters as well as mechanistic routes pertinent to the destruction of TBBA. We illustrated reaction networks for the synthesis of PXDD/Fs from BPhs and chlorinated phenols (CPhs). Similarly, we described pathways leading to the formation of PBDFs and polybrominated diphenylethers (PBDEs) from brominated benzenes (BBzs). We critically reviewed the literature on BFR thermal decomposition with specific foci on underlying mechanisms, decomposition products, the influence of the polymeric matrix, metallic content and operational conditions. As BCPhs are direct building blocks for the formation of PXDD/Fs, we computed the thermochemical parameters of their complete series. We calculated standard enthalpies of formation, entropies, heat capacities and bond dissociation enthalpies (BDHs) of O-H bonds for the complete series of BCPhs. Values of the acid dissociation constant (pKa) were estimated based on an accurate thermodynamic cycle incorporating solvation and protonation energies. Calculated values of BDHs of O-H bonds in BCPhs vary slightly with the change in degree and pattern of halogenation. Gibbs energies of solvation of BCPhs in water are highly exergonic, with their values increasing with the degree of halogen substitution. Values of pKa dictate that BCPhs characterised by high degrees of halogenation display stronger acidity and dissociate more easily in aqueous media (i.e., they are stronger acids than lower substituted phenols). Photolysis and photochemical decomposition are important channels for the degradation of halogenated organic pollutants in the environment. Therefore, we performed density functional theory (DFT) and time-dependent density functional theory (TDFT) calculations in order to derive the photodecomposition properties of major deployed BFRs and congeners of BPhs in both gaseous and aqueous media. We clarified the effect of degree and pattern of bromination on the photodebromination of selected brominated aromatic compounds based on several molecular descriptors; namely, geometries of the ground (S0) and electronically first excited (S1) states, values of the HOMO-LUMO energy gap (EH-L) and atomic charges on bromine atoms (qBr). Molecules exhibit different geometries in the S0 and S1 states and C-Br bonds elongate upon S0 → S1 transitions. In agreement with the recent findings on PBDEs, we found that the photoreactivity of bromine atoms in investigated BFRs and BPhs followed the sequence of ortho > meta > para. The bromine atom connected to the ortho-position holds the highest positive atomic charge and, thus, experiences the greatest lengthening of C-Br bonds in the S1 state, in both gaseous and an aqueous media, prompting their reductive debromination. Excitation energies decrease linearly with increasing numbers of bromine substituents, and congeners with a high degree of bromination photodecompose more readily than lower brominated isomers. Computed values of EH-L for major BFRs and their non-brominated molecules inferred that the number of bromine substituents and the nature of the structure (aromatic/non-aromatic) contributes significantly towards the photoreactivity of molecules. We conducted gas phase thermal decomposition of TBBA using a laboratory-scale tubular reactor. Our main focus was to identify pollutants arising in the temperature range of 673 – 1123 K following evaporation of TBBA in the gas phase. The identification and quantitation involved the use of a gas chromatograph – triple quadrupole mass spectrometer (GC-QQQMS) instrument, functioning in multiple reaction monitoring (MRM) and total ion current (TIC) modes. Product analysis revealed that thermal decomposition of TBBA commenced at 723 K. The major decomposition products were HBr, di-tribrominated bisphenols, benzene, phenol, mono-tribrominated congeners of benzene and phenol, brominated and non-brominated alkylated benzenes, benzofuran, bromobenzofuran, dibenzofuran, bromine substituted polyaromatic hydrocarbons (PAHs), biphenyl and biphenylene. We observed that, most of the decomposition products evolved in trivial concentrations at a temperature of 773 K and peaked at around 923 – 973 K. Higher temperatures favour the generation of non-brominated products. In this chapter, we have performed quantum chemical calculations to derive the degradation pathways of TBBA and to illustrate routes for the formation of brominated and non-brominated species. We constructed formation mechanisms related to the emission of PBDD/Fs in systems involving BFRs. In particular, we investigated formation corridors of (i) PXDD/Fs from the coupling reactions of 2-chlorophenoxy (2-CPhxy) and 2-bromophenoxy (2-BPhxy) radicals, (ii) PBDFs and PBDEs synthesis from the condensation reaction of monobromobenzene (MBBz) and a 2-BPhxy radical. The coupling reactions of 2-BPhxy and 2-CPhxy radicals produce keto-ether (through the additions of a phenoxy O at ortho C(H), C(Cl) and C(Br) sites) and diketo (at ortho positions to C–C bridges) structures. Keto-ethers act as direct intermediates for the formation of dioxin moieties such as dibenzo-p-dioxin (DD), 1-monochlorodibenzo-p-dioxin (1-MCDD), 1-monobromodibenzo-p-dioxin (1-MBDD), 1-bromo-6-chlorodibenzo-p-dioxin (1-B,6-CDD) and 1-bromo-9-chlorodibenzo-p-dioxin (1-B,9-CDD) molecules. Diketo adducts initiate the formation of furan species, i.e., 4-monochlorodibenzofuran (4-MCDF), 4-monobromodibenzofuran (4-MBDF) and 4-bromo-6-chlorodibenzofuran (4-B,6-CDF) compounds, through interconversion and rearrangement reactions. We found that, these mechanisms of formation, commencing from halogenated phenoxy radicals, are largely insensitive to patterns and degrees of halogenation on meta and para sites. It follows that, our developed mechanistic and kinetic factors of reactions involving 2-BPhxy and 2-CPhxy should also apply to higher halogenated phenoxy radicals. We explored the initial oxidative decomposition pathways of monobromobenzene (MBBz) in the generation of BPhxy radicals and examined the possible dimerisation reactions of MBBz and 2-BPhxy. It was found that, the coupling of MBBz and 2-BPhxy results in the generation of twelve pre-PBDF intermediates, of which four can also serve as building blocks for the synthesis of PBDEs. The resonance-stabilised structure of the o-BPhxy radical accumulates more spin density character on its phenoxy O atom (30.9 %) in reference to ortho-C and para-C sites. Thus, the formation of the pre-PBDE/pre-PBDF structures via O/o-C couplings advances faster, as it requires lower activation enthalpies (79.2 – 84.9 kJ mol-1) than the pre-PBDF moieties, which arise via pairing reactions involving o-C(H or Br)/o-C(H or Br) sites (97.2 – 180.2 kJ mol-1). Kinetic analysis indicates that the O/o-C pre-PBDE/pre-PBDF adducts self-eject the out-of-plane H atoms to produce PBDEs, rather than undergo a three-step mechanism that forms PBDFs. Since the formation mechanisms of PBDFs and PBDDs are typically only sensitive to the bromination at ortho positions, the results reported herein also apply to higher brominated isomers of BBzs. Overall, this thesis provides novel and comprehensive information on the thermochemical properties of the complete series of BCPhs (potential precursors to PXDD/Fs) and the electronic/structural characteristics of BFRs and their derived BPhs, with regards to their photodecomposition. To gain an insight into the degradation of TBBA once it has evaporated, this thesis examines the pure gas phase decomposition of TBBA and suggests mechanisms by which the experimentally-detected volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) are generated. Furthermore, this thesis explores the role of BPhs and CPhs as building blocks for the formation of PXDD/Fs, and computes their parameters. We also elucidate reaction pathways and thermo-kinetic parameters for PBDFs and PBDEs produced by the oxidation of BBzs.

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CARLE, AXEL BJORN. « A Mechanistic Investigation of the Photochemical and Thermal Activation of 2,2- and 2,3-Diaryl- and 2,2,3-Triaryl-2,3-dihydro-phenanthro[9,10-b]-1,4-dioxins, a New Class of 1,4-Dioxene Based DNA Cleaving Agents ». University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1016478287.

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Phan, Duong Ngoc Chau. « The relationship between fly ash chemistry and the thermal formation of polychlorinated pollutants during waste incineration ». Doctoral thesis, Umeå universitet, Kemiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-80186.

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The thermal formation of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and naphthalenes (PCNs) is a major problem in waste incineration. Ideally, rather than relying on air cleaning systems and treatment techniques, their formation should be minimized or, if possible eliminated. The work presented in this thesis was conducted to obtain a deeper understanding of the thermal formation of PCDDs, PCDFs, PCBs, and PCNs during incineration using a 5 kW laboratory scale incinerator and two artificial wastes that were designed to reflect regional differences in waste composition. The first part of the thesis focuses on the validation of a recently-developed flue-gas sampling probe with enhanced cooling capabilities. Artifact formation of PCDDs and PCDFs can occur during the sampling of hot flue gases if the cooling is insufficient. The new probe was successfully used to collect samples at 700 °C without biasing the measured POP levels. The thermal formation of PCDDs, PCDFs, PCBs, and PCNs in the post-combustion zone of the incinerator was then studied by collecting flue gas samples at 400 °C, 300 °C, and 200 °C during the incineration of the two artificial wastes. Highly chlorinated POPs were formed in larger quantities when burning the waste with the higher content of metals and chlorine, which suggests that high metal levels in the waste favor the chlorination of less chlorinated POPs or otherwise facilitate the formation of highly chlorinated polyaromatics, possibly via the condensation of highly chlorinated phenols. The concentrations of these pollutants and the abundance of highly chlorinated homologues increased as the flue gas cooled. Fly ash particles play an important role in thermal POP formation by providing essential elements (carbon, chlorine, etc.) and catalytic sites. The chemical and mineralogical properties of fly ash samples were studied by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR), Scanning Electron Microscopy/Energy Dispersive X-ray (SEM/EDX), and X-ray photoelectron spectroscopy (XPS) to determine their impact on thermal POP formation. Orthogonal Partial Least Squares (OPLS) modeling was used to identify correlations between the observed POP distributions and the physicochemical data. This investigation provided new insights into the impact of fly ash chemistry on thermal POP formation. In addition, the POP isomer distribution patterns generated during waste combustion were examined. These patterns are used to “fingerprint” mechanisms of POP formation. It was found that wastes containing large quantities of metals and chlorine favored the formation of highly chlorinated homologues including the very toxic 2,3,7,8-congeners. The data suggest that reducing fly ash emissions might increase the SO2 content of the flue gas and thereby suppress the Deacon process and the formation of harmful highly chlorinated aromatic species.

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Livres sur le sujet "Dioxins formation"

Stieglitz, L. Formation and decomposition of polychlorodibenzodioxins and furans in municipal waste incineration. [Springfield, Va.] : NTIS, 1988.

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National Council of the Paper Industry for Air and Stream Improvement (U.S.). An intensive study of the formation and distribution of 2,3,7,8-TCDD and 2,3,7,8-TCDF durring the bleaching of kraft pulps. New York, N.Y : National Council of the Paper Industry for Air and Stream Improvement, 1990.

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Li, Li. Minimizing organochlorine formation during chlorine dioxide bleaching. Ottawa : National Library of Canada, 1994.

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Burton, Krakow, Neuhauser Edward F, Altwicker Elmar R, New York State Energy Research and Development Authority., Niagara Mohawk Power Corporation et Rensselaer Polytechnic Institute, dir. Fundamental aspects of dioxin (PCDD) and furan (PCDF) formation from combustion : Final report. Albany, N.Y : NYSERDA, 1992.

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C, Thomas David, et Benson Sally, dir. Carb on dioxide capture for storage in deep geologic formations : Results from the COb2s Capture Project. Amsterdam : Elsevier, 2005.

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Fitzgerald, Garrett Christopher. Multi-scale Analysis of Methane Gas Hydrate Formation and Dissociation via Point Source Thermal Stimulation and Carbon Dioxide Exchange. [New York, N.Y.?] : [publisher not identified], 2014.

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R, Herring J., et Geological Survey (U.S.), dir. Methane, carbon dioxide, oxygen, and nitrogen in soil gas overlying coal beds of the Upper Cretaceous Fruitland Formation in the San Juan Basin, La Plata County, southwestern Colorado. [Denver, Colo.?] : U.S. Dept. of the Interior, U.S. Geological Survey, 1994.

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1923-, Walker Charls E., Bloomfield Mark A, Thorning Margo et American Council for Capital Formation. Center for Policy Research., dir. Strategies for improving environmental quality and increasing economic growth : Proceedings of a symposium sponsored by the American Council for Capital Formation, Center for Policy Research, held November 16, 1994 in Washington, D.C. Washington, D.C : ACCF, 1995.

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1923-, Walker Charls E., Bloomfield Mark A, Thorning Margo et American Council for Capital Formation. Center for Policy Research., dir. An economic perspective on climate change policies : Proceedings of a symposium sponsored by the American Council for Capital Formation, Center for Policy Research. Washington, D.C : ACCF Center for Policy Research, 1996.

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Alliance for the Chesapeake Bay et United States. National Oceanic and Atmospheric Administration, dir. Airsheds and watersheds : The role of atmospheric nitrogen deposition : a report of the Shared Resources Workshop, Airlie Conference Center, Warrenton, VA 22186, 11 & 12 October, 1995 : a formative document of the East Coast Atmospheric Resource Alliance. [Washington, D.C. ? : National Oceanic and Atmospheric Administration, 1997.

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Chapitres de livres sur le sujet "Dioxins formation"

Shahare, Vaishali V. « Sources and Formation of Dioxins and Furans ». Dans Techniques for Measurement and Removal of Dioxins and Furans, 19–32. Boca Raton, FL : CRC Press, 2017. | "A science publishers book." : CRC Press, 2017. http://dx.doi.org/10.1201/9781315154350-2.

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Buekens, Alfons, et Jim Swithenbank. « CFD Modelling of Industrial Plant from a Viewpoint of Dioxins Formation ». Dans Challenges of Power Engineering and Environment, 827–36. Berlin, Heidelberg : Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-76694-0_155.

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Nussbaumer, T., et P. Hasler. « Formation and Reduction of Polychlorinated Dioxins and Furans in Biomass Combustion ». Dans Developments in Thermochemical Biomass Conversion, 1492–506. Dordrecht : Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-009-1559-6_117.

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Buekens, Alfons, Palina Tsytsik et Robert Carleer. « Methods for Studying the de novo Formation of Dioxins at a Laboratory Scale ». Dans Challenges of Power Engineering and Environment, 738–47. Berlin, Heidelberg : Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-76694-0_138.

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Hemming, Jarl, Bjarne Holmbom et Bengt Larsson. « Formation of Chlorinated dibenzo-p-dioxins and Dibenzo Furans during Chlorination of Aquatic Humic Substances ». Dans Organic Micropollutants in the Aquatic Environment, 523–27. Dordrecht : Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3356-2_64.

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Shibamoto, Takayuki, Akio Yasuhara et Takeo Katami. « Dioxin Formation from Waste Incineration ». Dans Reviews of Environmental Contamination and Toxicology, 1–41. New York, NY : Springer New York, 2007. http://dx.doi.org/10.1007/978-0-387-36903-7_1.

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Van Ginneken, Luc, et Herman Weyten. « Particle Formation Using Supercritical Carbon Dioxide ». Dans Carbon Dioxide Recovery and Utilization, 123–36. Dordrecht : Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-0245-4_3.

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Jia, L., E. J. Anthony et D. L. Granatstein. « Dioxin and Furan Formation in FBC Boilers ». Dans Environmental Challenges and Greenhouse Gas Control for Fossil Fuel Utilization in the 21st Century, 43–58. Boston, MA : Springer US, 2002. http://dx.doi.org/10.1007/978-1-4615-0773-4_4.

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Loret, Benjamin. « Carbon Dioxide Sequestration and Enhanced Recovery Techniques ». Dans Fluid Injection in Deformable Geological Formations, 681–750. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-94217-9_9.

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Qanbari, Farhad, Olga Ye Zatsepina, S. Hamed Tabatabaie et Mehran Pooladi-Darvish. « CO2and Acid Gas Storage in Geological Formations as Gas Hydrate ». Dans Carbon Dioxide Sequestration and Related Technologies, 209–25. Hoboken, NJ, USA : John Wiley & Sons, Inc., 2011. http://dx.doi.org/10.1002/9781118175552.ch13.

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Actes de conférences sur le sujet "Dioxins formation"

Gogol, Elina V., Guzel I. Gumerova et Olga S. Egrova. « Approaches to Assessment and Hazard Identification of Dioxins ». Dans Environmental Engineering. VGTU Technika, 2017. http://dx.doi.org/10.3846/enviro.2017.021.

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In the Russian practice in the framework of environmental regulation sanitary measurements to assess the toxicity of the objects of the environment, which are based on the determination of standardized components concentrations and comparing them with the limit value, are widely used. But this approach doesn’t allow assessing the degree of biological hazards for organisms. The biotesting method has been considered for assessing the safety of dioxin-like compounds. Dioxins can be formed out of control in the environment. Ultraviolet radiation accelerates the formation of dioxins, as it enhances the ability of a chemical reaction of chlorine. This phenomenon is well known in Russia, where the chlorination is a standard procedure of water treatment and disinfection of drinking water, and control of the content of chlorophenols is an optional procedure. Simulation of the formation of dioxins in the process of chlorination of water, containing phenolic compounds, was carried out. Process of dioxins transformation in living systems to more toxic metabolites has been described. Enzymes that are involved in detoxification of dioxins have been identified. According to the results of bioassay danger of water samples, containing dioxins, is underestimated, since it doesn’t take into account specific features of metabolism of dioxins in living organisms. Under the action of enzymes in the cells the less toxic compounds can be converted into the more toxic in terms of carcinogenicity and mutagenicity. The system of determination of the dioxin toxic equivalency factor doesn’t account for it. Thus, during determination of danger of xenobiotics in living organisms we should move away from the determination of acute toxicity and focus on the processes that are started by enzyme systems when a toxicant gets into cells of living organisms.

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Themelis, N. J., et P. Deriziotis. « Substance and Perceptions of Environmental Impacts of Dioxin Emissions : An Interim Report ». Dans 11th North American Waste-to-Energy Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/nawtec11-1690.

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The emission of dioxins is perceived widely as a major environmental impact of combustion processes. This paper will report the results of an extensive study of published data on a) the rate of formation of dioxins from all U.S. sources; b) the pre-MACT and post-MACT performance of individual Waste-to-Energy (WTE) plants in the U.S. and how post-MACT emissions compare with the 1998 EU standard (0.1 ng/dscm); c) how the contribution of WTEs has changed with time; and d) the measured impacts of WTE dioxin emissions on soil/plant concentrations and on public health. The study has shown that since 1987 the U.S. dioxin emissions have decreased by a factor of four and by now WTEs are a miniscule source. Also, that even at the earlier high emission levels, the dioxin levels in soil samples close to WTE facilities did not exhibit an increase over regional background concentrations. Finally, the paper contrasts public perceptions of the dioxin threat with scientific studies of observed effects on the environment and on public health.

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Hou, S., B. Z. Dlugogorski, M. Altarawneh, J. C. Mackie et E. M. Kennedy. « Formation of Chlorinated Dibenzo-p-dioxins and Dibenzofurans (CDD/F) and Their Precursors in Oxidation of 4-Chlorobiphenyl ». Dans Proceedings of the Seventh International Seminar Fire and Explosion Hazards. Singapore : Research Publishing Services, 2013. http://dx.doi.org/10.3850/978-981-07-5936-0_06-02.

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Shimizu, Tadaaki, Hans-Ju¨rgen Franke, Satoko Hori, Yasuo Takano, Kazuaki Yamagiwa et Masato Tanaka. « In-Situ Hydrocarbon Capture and Reduction of Emissions of Dioxins by Porous Bed Material Under Fluidized Bed Incineration Conditions ». Dans 17th International Conference on Fluidized Bed Combustion. ASMEDC, 2003. http://dx.doi.org/10.1115/fbc2003-031.

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This work is intended to reduce emissions of dioxins and unburned gas from fluidized bed waste incinerators. Combustion of plastic pellets was conducted using a bench-scale bubbling fluidized bed combustor. Porous alumina was used as a bed material instead of conventional bed material (sand). First, we evaluated the effect of bed material on capture of volatile matter in the bed in a nitrogen atmosphere. Porous alumina captured volatile matter while sand did not. Feeding gas asymmetrically to enhance internal circulation of solids in the bed increased volatile capture efficiency of the porous alumina bed, whereas no improvement was found for the sand bed. Next, we performed combustion of plastic pellets by air. Emission of unburned gas was lower for the porous alumina bed than for the sand bed under a uniform gas feed condition. This is attributable to volatile matter capture by bed material that lengthens residence time of volatile matter in the combustor. However, non-uniform air feed for internal circulation was ineffective for suppressing unburned gas emissions. This may be caused by formation of an oxygen-deficient zone in the combustor. Finally, dioxin emissions were measured during PVC pellet combustion in a uniformly fluidized bed. The porous alumina bed was more effective for dioxin emission suppression than the sand bed.

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Babayan, E., A. Aleksandryan, V. Kogan, R. Hovanesyan, L. Saryan et A. Khachatryan. « 97. Possible Emissions of Dioxins at Chloroprene Production and Their Probable Role in Formation of Pathology Observed in Occupationally Exposed Workers ». Dans AIHce 2004. AIHA, 2004. http://dx.doi.org/10.3320/1.2758312.

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Themelis, Nickolas J. « Chlorine Sources, Sinks, and Impacts in WTE Power Plants ». Dans 18th Annual North American Waste-to-Energy Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/nawtec18-3577.

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The principal sources of chlorine in the MSW feed to WTE power plants are food wastes (e.g., wheat, green vegetables, melon, pineapple), yard wastes (leaves, grass, etc.), salt (NaCl), and chlorinated plastics (mostly polyvinyl chloride). Chlorine has important impacts on the WTE operation in terms of higher corrosion rate than in coal-fired power plants, formation of hydrochloric gas that must be controlled in the stack gas to less than the U.S. EPA standard (29 ppm by volume), and potential for formation of dioxins and furans. Past Columbia studies have shown that the chlorine content in MSW is in the order of 0.5%. In comparison, chlorine concentration in coal is about 0.1%; this results in much lower HCl concentration in the combustion gases and allows coal-fired power plants to be operated at higher superheater tube temperatures and thus higher thermal efficiencies. Most of the chlorine output from a WTE is in the fly ash collected in the fabric filter baghouse of the Air Pollution Control system. This study examined in detail the sources and sinks of chlorine in a WTE unit. It is concluded that on the average MSW contains about 0.5% chlorine, which results in hydrogen chloride concentration in the WTE combustion gases of up to 600 parts per million by volume. About 45% of the chlorine content in MSW derives from chlorinated plastics, mainly polyvinyl chloride (PVC), and 55% from salt (NaCl) and chlorine-containing food and yard wastes. An estimated 97–98% of the chlorine input is converted to calcium chloride in the dry scrubber of the Air Pollution Control (APC) system and captured in the fly ash collected in the baghouse; the remainder is in the stack gas at a concentration that is one half of the U.S. EPA standard. Reducing the input of PVC in the MSW stream would have no effect on dioxin formation but would reduce the corrosion rate in the WTE boiler.

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Duo, Wenli, Ibrahim Karidio, Larry Cross et Bob Ericksen. « Combustion and Emission Performance of a Hog Fuel Fluidized Bed Boiler With Addition of Tire Derived Fuel ». Dans 17th International Conference on Fluidized Bed Combustion. ASMEDC, 2003. http://dx.doi.org/10.1115/fbc2003-016.

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Salt-laden hog fuel (wood waste) is burnt in a fluidized bed boiler converted from a travelling grate boiler to generate steam for a specialty paper mill. The converted boiler has a design capacity of 156 t/h of steam from hog and actual generation has varied from 76 to 107% of the design capacity. The conversion has resulted in more stable operation, more complete combustion, less ash production, reduced boiler maintenance, and lower fossil fuel consumption. Tire derived fuel (TDF) is used as a supplementary fuel. With an energy content of 33 GJ/t for TDF, as compared to 8 GJ/t for wet hog, addition of 2–5% TDF by weight increased the bed temperature by an average of 55°C, stabilized and improved the combustion of low quality hog and high moisture content sludge. The impact of TDF addition was studied in detail. Stack emissions were tested and bottom and fly ash samples were analyzed. Although TDF contains 1% zinc and 5 to 7% steel wire, addition of TDF did not affect total particulate emissions from the boiler. SO2 emissions were increased due to the high sulfur content of TDF (1.6%). A good correlation was obtained from the test results, showing that the addition of TDF resulted in a reduction in both the total formation and the stack emissions of dioxins and furans.

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Valko, Peter, M. J. Economides, S. A. Baumgartner et P. M. McElfresh. « The Rheological Properties of Carbon Dioxide and Nitrogen Foams ». Dans SPE Formation Damage Control Symposium. Society of Petroleum Engineers, 1992. http://dx.doi.org/10.2118/23778-ms.

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Garci´a-Pen˜a, Francisco, Alejandro Mun˜oz-Mozos et Pedro Casero-Cabezo´n. « MBM (Meat and Bonemeal) Co-Gasification in IGCC Technology ». Dans ASME Turbo Expo 2002 : Power for Land, Sea, and Air. ASMEDC, 2002. http://dx.doi.org/10.1115/gt2002-30010.

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The potential use of MBM (Meat and Bone Meal) as fuel in a power plant has been recently originated by the mad cow disease, affecting not only Europe (the origin of the disease) but also other continents. MBM manufacturing companies have been forced to change their traditional ways of distribution due to the current ban of using MBM as cattle feed, therefore using a dumping site or an incinerator. To be considered as a fuel, several studies should be carried out. Preliminary characterisation of MBM showed a heating value higher than existing in coal, and a grain size acceptable to be mixed with regular fuel, hence appropriate to be brought into a boiler or a gasifier. Additionally, an expected advantage of using MBM in a gasification process was the possibility of using it as adequate slag/ash fusion agent (instead of traditional limestone), due to the high presence of Ca compounds. Related to environmental issues, the conventional thermal oxidation process (like incineration) shows several inconveniences, associated to the presence of hazardous compounds (like furans and dioxins) expected in organic matter combustion. There are few references of the existence of this kind of compounds in gasification process, but it is known that the existing reducing environment in a gasifier does not benefit its formation at all. Some of these issues were analysed in short duration full-scale tests developed in Puertollano IGCC Power Plant, owned by ELCOGAS, in which several MBM/regular fuel mixtures were tested. This paper describes the methodology used in these tests, fuel characteristics, main systems performance, and general conclusions about the viability of IGCC co-gasification using alternative fuels.

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Shedid, Shedid A., et Abdulrazag Yusef Zekri. « Induced Sulfur Deposition During Carbon Dioxide Miscible Flooding in Carbonate Reservoirs ». Dans 8th European Formation Damage Conference. Society of Petroleum Engineers, 2009. http://dx.doi.org/10.2118/119999-ms.

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Rapports d'organisations sur le sujet "Dioxins formation"

n. Environmental Assessment for Pilot Experiment for Geological Sequestration of Carbon Dioxide in Saline Aquifer Brine Formations, Frio Formation, Liberty County, Texas (October 2003). Office of Scientific and Technical Information (OSTI), octobre 2003. http://dx.doi.org/10.2172/837338.

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F.N. Somurskil, .R.C. Win et U.Ecke. Computational Investigation of the Formation of Hyperstoichiometric Uranium Dioxide (U02+X). US : Yucca Mountain Project, Las Vegas, Nevada, septembre 2006. http://dx.doi.org/10.2172/894738.

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Leckey, J. H. Polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran formation and emission in the thermal desorption waste treatment process. Office of Scientific and Technical Information (OSTI), mars 1995. http://dx.doi.org/10.2172/290997.

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Alan Byrnes, G. Paul Willhite, Don Green, Martin Dubois, Richard Pancake, Timothy Carr, W. Lynn Watney et al. Field Demonstration of Carbon Dioxide Miscible Flooding in the Lansing-Kansas City Formation, Central Kansas. Office of Scientific and Technical Information (OSTI), mars 2007. http://dx.doi.org/10.2172/902503.

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Alan Byrnes, G. Paul Willhite, Don Green, Martin Dubois, Richard Pancake, Timothy Carr, W. Lynn Watney et al. FIELD DEMONSTRATION OF CARBON DIOXIDE MISCIBLE FLOODING IN THE LANSING-KANSAS CITY FORMATION, CENTRAL KANSAS. Office of Scientific and Technical Information (OSTI), décembre 2005. http://dx.doi.org/10.2172/889724.

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