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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
341

Kennzeichnung von Schlachtnebenprodukten zur sicheren Klassifizierung als tierische Nebenprodukte der Kategorie 3 und zur Verbesserung ihrer Verfolgbarkeit im Warenstrom: Kennzeichnung von Schlachtnebenprodukten zur sicheren Klassifizierung als tierische Nebenprodukte der Kategorie 3 und zur Verbesserung ihrerVerfolgbarkeit im Warenstrom

Schmidt, Bianca 28 June 2011 (has links)
Die seit 2004 in Deutschland bekannt gewordenen Fälle der illegalen Rückführung und irrtümlichen Fehlverbringung von gemäß der Verordnung (EG) Nr. 1774/2002 nicht für den Genuss durch den Menschen bestimmten tierischen Nebenprodukten (TNP) der Kategorie 3 in die Lebensmittelkette haben zu der politischen Diskussion beigetragen, ob die Pflicht der Materialidentifizierbarkeit durch das Getrennthalten TNP am Ort des Anfalls sowie die ausschließliche Kennzeichnung ihrer Transportbehälter bei der Beförderung einen ausreichenden Schutz der Verbraucher garantieren können. Um eine ordnungsgemäße Verwendung TNP der Kategorie 3 sicherzustellen, hat der Bundesrat ihre unmittelbare und eindeutige Kennzeichnung, z.B. durch Farbstoffe, gefordert. Ziel dieser Arbeit war es, einen geeigneten, futtermittelrechtlich zugelassenen Marker für Schlachtnebenprodukte der Kategorie 3 zu erörtern, der eine technisch praktikable, vom Ort des Anfalls bis zum Verarbeitungsbetrieb optisch eindeutige, dauerhafte und nach der Verarbeitung nachweisbare sowie umwelt- und wirtschaftsverträgliche Markierung von Schlachtnebenprodukten zur sicheren Verfolgbarkeit ihrer bestimmungsgemäßen Verwendung als TNP der Kategorie 3 ermöglicht, um ihren Eintrag in die Lebensmittelkette zu unterbinden, ohne die Neutralität der Endprodukte bei der Verwendung markierter TNP als Rohstoffe für Futtermittel zu beeinträchtigen. Für die Markierung von Schlachtnebenprodukten mittels Sprühsystemen wurden für Futtermittel zugelassene, färbende Zusatzstoffe (Verordnung (EG) Nr. 1831/2003) sowie in der medizinischen Diagnostik etablierte Fluoreszenz-Farbstoffe ausgewählt und hinsichtlich der Eindeutigkeit ihrer Markierung, ihrer Farbhaltung nach Bearbeitung sowie ihrer optischen Neutralität in Lebens- und Futtermitteln, die aus markierten TNP hergestellt worden sind, von fünf ungeschulten Prüfpersonen im Rahmen einer einfach beschreibenden, sensorischen und unabhängigen Prüfung gemäß §35 LMBG (L 00.90-6, ASU) beurteilt. Die Ergebnisse der sensorischen Prüfung wurden mit den RGB-Farbprofilen der markierten und nicht markierten TNP vergleichend analysiert. Zum Nachweis des irrtümlichen oder vorsätzlichen Eintrags von mit den ausgewählten Markerfarbstoffen markierten TNP in Lebensmitteln konnten die Analyseverfahren Dünnschichtchromatographie (DC), optische Emissionsspektrometrie mit induktiv gekoppeltem Hochfrequenzplasma (ICP-OES), Photometrie sowie die Fluoreszenzspektrometrie hinsichtlich ihrer Anwendbarkeit untersucht werden. Die Untersuchung der sensorischen Neutralität der Markerfarbstoffe im Endprodukt Futtermittel erfolgte unter anderem durch einen Futtermittelpräferenzversuch an neun Hunden der Rasse Beagle. Brillantsäuregrün E142 (1,3 mg E142/kg TNP) konnte auf Grund der Eindeutigkeit der Markierung von Schlachtnebenprodukten durch die gegenüber den nativen TNP signifikant unterschiedlichen Rot-Farbintensitäten bei gleichzeitiger Neutralität in den Endprodukten (Lebens- oder Futtermittel) und einer guten bis sehr guten Farbhaltung nach dem Waschen der Nebenprodukte, der Kühl- (8°C über zwei Tage) sowie Gefrierlagerung (-25°C über 14 Tage) und dem Verwenden einer 14, 90 als auch 150 Tage gelagerten Farbstofflösung in Kombination mit dem chemisch nachweisbaren Titandioxid (90 mg E171/ kg TNP) als Markerfarbstofflösung zur eindeutigen Markierung von Nebenprodukten der Schlachtung am Ort ihres Anfalls selektiert werden. Die für die Markierung bestimmten Dosierungen der Markerfarbstoffe gelten für Tiere und Menschen als unbedenklich. Die mit den färbenden Zusatzstoffen E142 und E171 markierten Nebenprodukte der Schlachtung können mittels DC (Nachweisgrenze: ≥7,5 µg E142/kg Probe) beziehungsweise ICP-OES und Photometrie (Nachweisgrenze ICP-OES: 8,3 mg E171/kg Probe) ab einem eingebrachten Anteil von 0,55% (DC: E142) beziehungsweise 9% (ICP-OES: E171) in diversen Produkten (Lebens- oder Futtermittel) nachgewiesen werden. In den chemisch und thermisch extrahierten Fetten aus markierten, fettreichen TNP waren die Farbstoffe E142 und E171 jedoch nicht nachweisbar. Eine Fluoreszenzmarkierung TNP kann hingegen nicht präferiert werden, da nicht markierte Nebenprodukte der Schlachtung eine sichtbare und fluoreszenzspektrometrisch nachweisbare Autofluoreszenz aufweisen und in den thermisch verarbeiteten Produkten keine für die Fluoreszenz-farbstoffe charakteristischen Absorptions- und Emissionsspektren nachweisbar waren. Die Markierung mittels Sprühtechnik erscheint unter den Aspekten Substanzverlust und adaptierter Markerfarbstoff pro Kilogramm TNP praktikabel. Die im Labor bestimmte Markierungszeit für TNP (5 sec./kg) ist unter Einbeziehung der Durchsatzraten am Schlachthof als zu lang zu bewerten. Durch die rückstandsfreie Entfernung der Farbstoffe von Edelstahl- und glatten Kunststoffflächen sowie glasierten Fliesen ergeben sich keine Nachteile der Markierung TNP für die Produktion von Futtermitteln und technischen Erzeugnissen. Die in dem Präferenzversuch untersuchten Futtermittel für Hunde aus markierten TNP zeigten keine Abweichungen von der handelsüblichen sensorischen Produktqualität und hinsichtlich ihrer Haltbarkeit durch Sterilisation (F0-Wert). Mit E142 und E171 markierte TNP (Kat. 3) eignen sich somit als Rohstoffe zur Herstellung von Heimtierfuttermitteln. Bei Anwendung einer Kombinationsfarbstofflösung (E142 und E171) würden die für die Marker anfallenden Kosten pro Tonne TNP bis zu 33 Euro betragen. Bei der ausschließlichen Verwendung von E142, welches der optisch eindeutig markierende Farbstoff ist und das eine hohe Sensitivität im dünnschichtchromatographischen Nachweis zeigt, würden die Kosten 1,70 bis 3,40 Euro/t betragen. Bisher konnte kein EU-einheitlicher Rechtsrahmen zur Markierung TNP der Kategorie 3 gestaltet werden. Die politische Diskussion wird aber vor allem national fortgesetzt. / Since 2004 several illegal or aberrant transfers of animal by-products (ABP) from category 3 (according to Regulation (EC) No. 1774/2002: not intended for food production) back into food chain, have led to the political discussion, whether duty of material identifiability by separate storing of ABP on site and sole labeling of containers during transport are sufficient to protect consumers from ABP not intended for human consumption. To guarantee adequate utilisation of ABP from category 3, the German Federal Council claimed for an immediate and conclusive marking of ABP by dyeing or similar solutions. This study was implemented to define a convenient, registered feed additive for dyeing of slaughter by-products from category 3, which realize a feasible, from extraction to processing visually conclusive, long-lasting, traceable as well as sustainable and cost-effective marking on site to ensure traceability of intended utilisation as ABP from category 3 and to prevent their influx into food chain, without an impairment of the neutrality of products (e.g. pet food) made from marked ABP. For marking of slaughter by-products by air spraying device, registered colouring feed additives (Regulation (EC) No. 1831/2003) as well as diagnostically established fluorescence pigments were selected and investigated regarding their marking unambiguousness, colour retention after processing and visual neutrality in food and feed made from marked ABP by evaluation of five untrained judging persons in the course of a simply delineative, sensorial and impartial test (official list of analysis methods, ASU §35 LMBG, L 00.90-6), and by comparative RGB-colour measurement of images scanned from stained ABP samples. Detection of aberrant or deliberate discharge of marked ABP into food production was evaluated by investigation of thin layer chromatography (TLC), inductively coupled plasma optical emission spectrometry (ICP-OES), photometry and fluorescence spectrometry. Neutrality of marking feed additives in feedstuff was determined by a feeding preference test with nine dogs of the Beagle breed using pet food made from unmarked und marked ABP. Lissamine Green E142 (1,3 mg E142 per kg ABP) was selected as marker dye for slaughter by-products on site based on its unambiguousness of marking due to the significant different red-colour intensity compared to the non-marked ABP as well as the simultaneous neutrality of the colouring additive E142 in the final products feed and food. Colour retention of E142 marking was conclusive with regard to handling by washing, cold (8°C for two days) respectively fridge storage (-25°C for 14 days) and utilisation of a 14-, 90- and 150-days-stored marker solution. For marking, Lissamine Green was combined with the chemical detectable and registered food colour titanium dioxide (E171: 90 mg/kg ABP). The marker additives are classified as safe for humans and animals within the preferred concentrations for colouring ABP. With E142 und E171 marked ABP were traceable in food and feed using detection methods TLC (limit of detection: ≥7,5 µg E142 per kg sample), photometry and ICP-OES (limit of detection: ≥8,3 mg E171 per kg sample) at a proportion of 0,55% (TLC: E142) respectively 9% (ICP-OES: E171), whereas the named markers were not detectable in chemical and thermal extracted fats produced from marked high-fat ABP. Based on the visible and fluorescence spectrometric detectable autofluorescence of animal tissues as well as the uncharacteristic emission and absorption spectra of fluorescence pigments in processed ABP, fluorescence markers are not preferential for marking of slaughter by-products from category 3. Marking of slaughter by-products by air spraying device appeared practicable in due consideration of marker depletion and tissue-adapted marker per kg ABP. Current time of marking under laboratory conditions (5 sec. per kg ABP) must be graded as too long, regarding high transfer rates in slaughterhouses. Concerning the residue-free cleaning of stainless steel and even plastic surfaces from the marker solution, the utilisation of marked ABP for manufacturing of feed and technical products is unproblematic. Investigated pet food samples produced from marked ABP were from comparable commercial sensory product quality and showed no deviation of normal storability due to sterilisation. In conclusion, with E142 and E171 visible marked ABP from category 3 are suitable as crude materials for pet food production. The application of the combined marker solution (E142 and E171) have to be evaluated as comparative expensive (33 Euro per ton ABP), while the exclusive application of E142 as the optic conclusive and sensitive detectable marker for ABP is associated with sustainable costs from 1,70 to 3,40 Euro per ton ABP. To date, an EU-common regulatory framework for marking of ABP from category 3 could not be specified. Nevertheless the political discussion is still continued, especially in Germany.
342

Résine échangeuse d’ions en mode biologique pour l’enlèvement de matières organiques naturelles des eaux de surface

Liu, Zhen 08 1900 (has links)
La matière organique naturelle (MON) est omniprésente dans les eaux de surface. Bien que l’exposition à la MON via l’eau potable soit commune et ne soit pas associée à des effets directs sur la santé humaine, la MON peut avoir des impacts négatifs sur la production d’eau potable, tels que la contribution aux goûts et odeurs, le développement du biofilm dans les systèmes de distribution et la formation de sous-produits de désinfection. La résine échangeuse d’ions en mode biologique (en anglais : Biological ion exchange, BIEX) est un processus prometteur pour l’enlèvement de la MON des eaux de surface. Il s’agit d’opérer la résine échangeuse d’ions dans un réacteur à lit fixe avec une régénération peu fréquente de sorte qu’une communauté microbienne peut se développer sur la surface de résine et ainsi contribuer à l’enlèvement de la MON par biodégradation. Néanmoins, les mécanismes de l’enlèvement de la MON dans le BIEX et la faisabilité de son application dans l’usine de production d’eau potable demeurent inconnus. Ainsi, l’objectif de cette thèse est 1) de comprendre et favoriser l’application du BIEX pour l’enlèvement de la MON des eaux de surface et 2) de résumer les stratégies qui peuvent alléger la gestion de la saumure engendrée par la régénération de résines. Les résines en forme chlorure et bicarbonate ont été d’abord évaluées pour l’application du BIEX où le pilote de BIEX a été alimenté par l’eau de surface pendant 9 mois sans régénération. Les résultats ont démontré que l’échange d’ions est le mécanisme dominant pour le BIEX, i.e., la MON échange avec les ions préchargés (i.e., chlorure et bicarbonate) et les ions préretenus (i.e., sulfate). En plus, les résines colonisées ont été prélevées du pilote et testées en laboratoire où les résines colonisées ont été mises en contact avec les composés de modèles (i.e., micropolluants organiques). Les résultats ont démontré que la biodégradation contribuait à l’enlèvement de micropolluants organiques sur les résines colonisées, mais le degré de biodégradation dépend des caractères de micropolluants organiques et la communauté microbienne sur les résines. Ensuite, le BIEX a été évalué en parallèle du charbon actif biologique (CAB) en filtration secondaire dans l’usine de production d’eau potable de Sainte-Rose. Les résultats ont démontré que bien que le BIEX ait réalisé un enlèvement du carbone organique dissous (COD) plus élevé par rapport à celui du CAB, il a une perte de charge plus significative et le rétrolavage de BIEX s’avère être plus complexe par rapport à celui de CAB. Finalement, une revue de littérature a été menée afin d’identifier les stratégies sur l’opération de résine et la gestion de saumure, et ainsi d’alléger la gestion de la saumure engendrée par la régénération de résines échangeuses d’ions. En somme, cette thèse permet de comprendre les mécanismes de l’enlèvement de la MON dans le BIEX, évaluer la faisabilité de son application dans l’usine de production d’eau potable ainsi qu’identifier les stratégies qui peuvent alléger la gestion de la saumure engendrée par la régénération de résines échangeuses d’ions. / Natural organic matter (NOM) is ubiquitous in surface water. Although the exposure to NOM via drinking water is common and is not associated with direct effects on human health, NOM can cause negative impacts on drinking water treatment, such as contribution to taste and odors, development of biofilms in distribution systems and formation of disinfection by-products. Biological ion exchange (BIEX) is a promising process for the removal of NOM from surface waters. It involves operating the ion exchange resin in a fixed bed reactor with infrequent regeneration so that a microbial community can develop on the resin surface and thus contribute to the removal of NOM by biodegradation. However, the mechanisms for the removal of NOM in BIEX and the feasibility of its application in the drinking water plant remain unknown. Therefore, the general objective of this thesis is 1) to understand and promote the application of BIEX for the removal of NOM from surface water and 2) to summarize the strategies that can alleviate the management of the brine generated by the regeneration of resins. Chloride and bicarbonate-form resins were first evaluated for the BIEX application where the BIEX pilot was fed with surface water for 9 months without regeneration. The results demonstrated that ion exchange is the dominant mechanism in BIEX, i.e., NOM exchanges with preloaded ions (i.e., chloride and bicarbonate) and pre-retained ions (i.e., sulfate). In addition, the colonized resins were harvested from the pilot and tested in the laboratory where the colonized resins were in contact with the model compounds (i.e., organic micropollutants). The results demonstrated that biodegradation contributes to the removal of organic micropollutants on colonized resins, but the extent of biodegradation depends on the characteristics of the organic micropollutants and the microbial community on the resins. Then, BIEX was evaluated in parallel with biological activated carbon (BAC) at the second-stage filtration of the Sainte-Rose drinking water treatment plant. The results demonstrated that although BIEX achieved higher dissolved organic carbon (DOC) removal compared to BAC, it had a more significant pressure drop and the backwash of BIEX filters was proved to be more complex compared to that of BAC. Finally, a literature review was carried out to identify strategies on resin operation and brine management, and thus alleviate the management of the brine generated by the regeneration of ion exchange resins. Overall, this thesis allows understanding the mechanisms for the removal of NOM in BIEX, evaluating the feasibility of its application in drinking water production plants as well as identifying the strategies that can alleviate the management of the brine generated by the regeneration of ion exchange resins.
343

Dezinfekce bazénových vod vybraných provozů / Disinfection of pool water of selected operations

Novotný, Hana January 2022 (has links)
The work presents an overview of swimming pool disinfection technologies of selected operations. Selected indoor and outdoor pool operations were to be described, and the use of chlorine and chlorine-free disinfectants was to be determined and the data evaluated. These goals were met in the theoretical part of the thesis, which presents the current methods of treatment and disinfection of swimming pool water and compares their advantages and disadvantages. The comparison includes advantages and disadvantages, use and costs of disinfection methods, individual water quality indicators, and their importance and measurements. The work also focuses on microbiological and chemical health risks from swimming pool water. The practical part described the technologies of swimming pool water treatment in six selected swimming pool operations, focusing on the use of chlorine and chlorine-free disinfectants and their operation. Another 27 operators in the Czech Republic (combined, indoor and outdoor) were contacted in writing for the survey. A total of 27 indoor and 23 outdoor operations were compared in the survey.
344

Performance and mechanism on a high durable silica alumina based cementitious material composed of coal refuse and coal combustion byproducts

Yao, Yuan 01 January 2012 (has links)
Coal refuse and combustion byproducts as industrial solid waste stockpiles have become great threats to the environment. Recycling is one practical solution to utilize this huge amount of solid waste through activation as substitute for ordinary Portland cement. The central goal of this dissertation is to investigate and develop a new silica-alumina based cementitious material largely using coal refuse as a constituent that will be ideal for durable construction, mine backfill, mine sealing and waste disposal stabilization applications. This new material is an environment-friendly alternative to ordinary Portland cement. The main constituents of the new material are coal refuse and other coal wastes including coal sludge and coal combustion products (CCPs). Compared with conventional cement production, successful development of this new technology could potentially save energy and reduce greenhouse gas emissions, recycle vast amount of coal wastes, and significantly reduce production cost. A systematic research has been conducted to seek for an optimal solution for enhancing pozzolanic reactivity of the relatively inert solid waste-coal refuse in order to improve the utilization efficiency and economy benefit for construction and building materials. The results show that thermal activation temperature ranging from 20°C to 950°C significantly increases the workability and pozzolanic property of the coal refuse. The optimal activation condition is between 700°C to 800°C within a period of 30 to 60 minutes. Microanalysis illustrates that the improved pozzolanic reactivity contributes to the generated amorphous materials from parts of inert aluminosilicate minerals by destroying the crystallize structure during the thermal activation. In the coal refuse, kaolinite begins to transfer into metakaol in at 550°C, the chlorite minerals disappear at 750°C, and muscovite 2M 1 gradually dehydroxylates to muscovite HT. Furthermore, this research examines the environmental acceptance and economic feasibility of this technology and found that this silica alumina-based cementitious material not only meets EPA requirements but also shows several advantages in industrial application.
345

Trihalomethane Removal and Re-Formation in Spray Aeration Processes Treating Disinfected Groundwater

Smith, Cassandra 01 January 2015 (has links)
Historically, chlorination has been widely utilized as a primary and secondary disinfectant in municipal water supplies. Although chlorine disinfection is effective in inactivating pathogenic microbes, the use of chlorine creates the unintentional formation of regulated chemicals. On January 4, 2006, the United States Environmental Protection Agency (EPA) promulgated the Stage 2 Disinfectants/Disinfection by-product rule (DBPR) that focuses on public health protection by limiting exposure to four trihalomethanes (THM) and five haloacetic acids (HAA5), formed when chlorine is used for microbial pathogen control. This thesis examines post-aeration TTHM formation when employing spray-aeration processes to remove semi-volatile TTHMs from chlorinated potable water supplies. A bench scale air stripping unit was designed, constructed and operated to evaluate spray aeration for the removal of the four regulated trihalomethane (THM) species from potable drinking water including bromodichloromethane, bromoform, dibromochloromethane, chloroform. The study was conducted using finished bulk water samples collected from two different water treatment facilities (WTFs) located in Oviedo and Babson Park, Florida. Both treatment plants treat groundwater; however, Oviedo's Mitchell Hammock WTF (MHWTF) supply wells contain dissolved organic carbon and bromide DBP precursors whereas the Babson Park WTF #2 (BPWTF2) supply well contains dissolved organic carbon DBP precursors but is absent of bromide precursor. Three treatment scenarios were studied to monitor impacts on total trihalomethane (TTHM) removal and post-treatment (post-aeration) TTHM formation potential, including 1) no treatment (non-aerated control samples), 2) spray aeration via specially fabricated GridBee® nozzle for laboratory-scale applications, 3) spray aeration via a commercially available manufactured BETE® nozzle used for full-scale applications. Select water quality parameters, chlorine residual, and total trihalomethane concentrations were monitored throughout the study. The GridBee® spray nozzle resulted in TTHM removals ranging from 45.2 ± 3.3% for the BPWTF2 samples, and 37.7 ± 3.1% for the MHWTF samples. The BETE® spray nozzle removed 54.7±3.9% and 48.1±6.6% of total trihalomethanes for the Babson Park and Mitchell Hammock WTF samples, respectively. The lower percent removals at the MHWTF are attributed to the detectable presence of bromide and subsequent formation of hypobromous acid in the samples. Post spray aeration TTHM formation potentials were monitored and it was found that the MHWTF experienced significantly higher formation potentials, once again due to the presence of hypobromous acid which led to increases in overall TTHM formation over time in comparison with the Babson Park WTF #2 TTHM formation samples. In addition, chlorine residuals were maintained post spray aeration treatment, and initial chlorine residual and trihalomethane concentrations did not significantly impact overall spray nozzle performance. Among other findings, it was concluded that spray nozzle aeration is a feasible option for the Babson Park WTF #2 for TTHM compliance. For Oviedo's Mitchell Hammock WTF spray aeration was successful in removing TTHMs, however it was not effective in maintaining DBP rule compliance due to the excessive nature of DBP formation in the water samples. This study was not intended to serve as an assessment of varying nozzle technologies; rather, the focus was on the application of spray aerators for TTHM removal and post-formation in drinking water systems.
346

Evaluating Leachability of Residual Solids Generated from Unconventional Shale Gas Production Operations in Marcellus Shale

Sharma, Shekar 17 September 2014 (has links)
Hydraulic fracturing operations utilized for shale gas production result in the generation of a large volume of flowback and produced water that contain suspended material, salts, hydrocarbons, metals, chemical additives, and naturally-occurring radioactive material. The water is impounded at drilling sites or treated off-site, resulting in significant generation of residual solids. These are either buried on site or are disposed in lined landfills. The objective of this study was to determine the levels of heavy metals and other elements of concern that will leach from these residual solids when placed in typical disposal environments. For this purpose, laboratory leaching experiments were employed wherein representative samples were brought into contact with a liquid to determine the constituents that would be leached by the liquid and potentially released into the environment. The samples used included sludge resulting from the physicochemical treatment of process water (TS), sludge solidified with cement kiln dust (SS), raw solids obtained by gravity separation of process water (RS), and drilling mud (DM). The samples were subjected to both single extraction (i.e. Shake Extraction Test, SET) and multiple extraction (i.e. Immersion Test, IT) leaching tests. For the shake extraction test, samples were mixed with a specific amount of leaching solution without renewal over a short time period. In the immersion test, samples were immersed in a specific amount of leaching solution that was periodically renewed over a longer period of time. For both these tests, analyses were performed on the filtered eluate. The tests were performed as per standards with modifications. Distilled de-ionized water, synthetic acid rain (pH ~ 4.2), weak acetic acid (pH ~ 2.88), and synthetic landfill leachate were used as leaching solutions to mimic specific disposal environments. Alkali metals (Li, K, Na), alkaline earth metals (Ba, Ca, Mg, Sr) and a halide (Br), which are typically associated with Marcellus shale and produced waters, leached at high concentrations from most of the residual solids sample. The SS sample, due to its stabilization with CKD, had a lower extraction efficiency as compared to the unconsolidated TS and RS samples. In EF 2.9 and EF SLL, the leaching took place under acidic conditions, while for EF DDI and EF 4.2, the leaching occurred in alkaline conditions. EF 2.9 and EF SLL were determined to be the most aggressive leaching solutions, causing the maximum solubility of most inorganic elements. Thus, high amounts of most EOCs may leach from these residual solids in MSW landfills disposed under co-disposal conditions. Agitation, pH and composition of the leaching solution were determined to be important variables in evaluating the leaching potential of a sample. The results of this study should help with the design of further research experiments being undertaken to develop environmentally responsible management/disposal strategies for these residual solids and also prove useful for regulatory authorities in their efforts to develop specific guidelines for the disposal of residuals from shale gas production operations. / Master of Science
347

Boisement d'une ancienne mine de chrysotile du sud du Québec : essais de divers types de technosols et d'essences ligneuses

Grimond, Laurence 04 1900 (has links)
L’industrie minière de l’amiante a profondément transformé les paysages du sud du Québec, laissant environ 800 millions de tonnes de résidus miniers sous la forme de haldes près des villes minières telles Thetford Mines et Black Lake. Certains enjeux environnementaux découlant de ces paysages, notamment l’érosion des haldes par le vent et l’eau, ont été atténués avec succès sur certains sites en les recouvrant de technosols composés d’un mélange de matières résiduelles fertilisantes, puis en les ensemençant avec des graminées. Cependant, aucune tentative de boisement n’avait été faite jusqu’à présent, car ces milieux étaient considérés comme trop contraignants pour l’établissement et la croissance des arbres. Dans cette étude, nous avons développé deux plantations expérimentales dans une mine d’amiante en déclassement dans le sud du Québec, sur des stériles et sur des résidus miniers, dans lesquelles a été comparée la performance de huit espèces d’arbres, clones et provenances plantés sur deux types de technosols, tous deux construits à partir d’un mélange de biosolides municipaux et de boues de désencrage aménagés en andains. Les propriétés physiques et chimiques des technosols, comme l’état hydrique et l’activité ionique du sol, ainsi que la survie et la croissance des arbres, ont été évaluées. La nutrition foliaire et l’utilisation de l’eau ont également été étudiées pour trois clones de peupliers hybrides au cours de leur troisième saison de croissance. Les clones de peupliers hybrides avaient une survie significativement plus élevée (87 à 94 %) après trois ans que toutes les espèces de conifères (10 à 56 %) testées. L'espèce résineuse présentant les taux de survie les plus élevés était l'épinette blanche (46 à 56 %). Les conditions sèches lors de la mise en terre peuvent en partie expliquer les taux de mortalité plus élevés des conifères. Les taux de croissance moyens des peupliers hybrides étaient de 45 cm an-1, alors que certains arbres atteignaient plus de 300 cm de hauteur après trois ans. Le phosphore et le potassium étaient les nutriments qui limitaient le plus la croissance. Le clone DN×M-915508 semble être le plus tolérant à la sécheresse. Bien qu'il y ait peu de différences entre les technosols, les résultats suggèrent que l'ajout de sols contaminés de classe B au mélange de matières résiduelles fertilisantes a des avantages pour la survie et la croissance des arbres, probablement en raison du volume de sol plus élevé. Notre étude a démontré une technologie prometteuse pour la remise en état par le boisement des mines d’amiante du sud du Québec. Certains traitements devraient être ajoutés pour limiter la concurrence des plantes au cours des premières années afin d'augmenter la survie et la croissance des arbres, alors qu'un volume limité de technosol et donc une faible disponibilité en humidité et en nutriments pourraient compromettre la croissance à moyen et long terme des arbres. / The asbestos mining industry has deeply transformed the landscapes of southern Quebec, leaving about 800 million tons of tailings and waste rock in large piles near former mining towns such as Thetford Mines and Black Lake. Some of the environmental issues arising from these landscapes (e.g. wind and water erosion) have been successfully addressed at some sites by covering the piles with a mixture of by-products as the technosol and then seeding with grasses. However, no attempt for afforestation had been made thus far because these environments were thought to pose too many constraints on tree establishment and growth. In this study, we developed two experimental plantations at a decommissioned asbestos mine in southern Quebec, on waste rocks and on tailings, as a means to test the performance of eight tree species/clones/provenances planted on two types of technosols, both mainly constructed from the mixing of municipal biosolids and deinking sludge and configured in small windrows. Physical and chemical properties of technosols, including soil water availability and ionic activity, and seedling survival and growth were assessed. Foliar nutrition and water use were also evaluated for three hybrid poplar clones during the third growing season. Hybrid poplar clones had significantly higher survival (87 to 94%) after three years than all conifer species (10 to 56%) tested, although dry conditions at planting could have had adverse effects on conifers. The conifer species exhibiting the highest survival rates was white spruce (46 to 56%). Average growth rates of hybrid poplars were 45 cm y-1, whereas some trees reached over 300 cm in height after three years. Clone DN×M-915508 is believed to be more drought tolerant than the other hybrid poplar clones tested. Phosphorus and potassium were the most growth-limiting nutrients. Although there were few differences between the technosols, results suggest that the addition of Class B contaminated soils to the main mixture of by-products has benefits regarding tree survival and growth, likely because of its larger volume. Our study demonstrated a promising technology for reclamation through afforestation of asbestos mines in southern Quebec. Some treatments should be added to limit plant competition within the first few years as a means to increase survival and growth, whereas limited technosol volume and thus low moisture and nutrient availability could compromise mid- to long-term growth of trees.
348

Iopamidol as a Precursor to DBP Formation in Drinking Water as a Function of Natural Matter and Bromide

Ackerson, Nana Osei Bonsu January 2017 (has links)
No description available.
349

En ekonomisk analys av biprodukterna från fossilfri vätgasproduktion : Undersökning av vätgasprojekt i Gävle hamn

Lindqvist, Oskar, Ellgren, Tommy January 2022 (has links)
In order to keep the Paris Agreement's goal of limiting global warming to well below 2°C, greenhouse gas emissions should be reduced. However, larger measures need to be implemented as it has been established that today's measures will not be enough. The Port of Gävle has plans to install a water electrolyser for hydrogen production of either Proton Exchange Membrane (PEM) or Alkaline Water Electrolysis(AWE). The size of the electrolyser will be approximately 10 MW and will have the capacity to produce 2,000 tons of fossil-free hydrogen per year that might supply 100 heavy trucks. However, it is currently cheaper with fossil hydrogen production. Therefore, an article review is conducted containing a calculation part where the purpose is to investigate the amount of by-products produced and whether they can be sold in other areas of use to make renewable hydrogen more economically competitive. Information for the study has been retrieved from databases, search engines, companies, authorities and individuals deemed relevant to the study. The by-products from the 10 MW electrolyser in the Port of Gävle have been compared with 1,5 MW and 17 MW electrolysers, then a sensitivity analysis has also beenperformed on the 10 MW electrolysers. The potentially generated heat depends on the type of electrolyser where AWE generates 77 MWh of residual heat per day and PEM potentially generates 67 MWh of residual heat per day. Furthermore, AWE needs 64 kWh of electricity to produce 1 kg of hydrogen while PEM needs 66,5 kWh of electricity per kg of hydrogen produced. Revenues from residual heat sales for AWE were estimated annually to approximately 7 million SEK and for PEM approximately 6 million SEK. For electrolysis-produced oxygen to compete with cryogenic oxygen, the price should not exceed 108 SEK/tonne. For the 10 MW electrolyser, oxygen sales are estimated to generate approximately 1,1 million SEK annually for both AWE and PEM. Total income for AWE will annually be just over 8,1 million SEK and 7.1million SEK annually for PEM. The AWE process is then preferable as it is more economically sustainable as the income from the by-products is 12% higher than PEM due to higher production of oxygen and greater generation of residual heat. / För att hålla Parisavtalets mål att begränsa den globala uppvärmningen till väl under 2°C bör utsläppen av växthusgaser minska. Däremot behöver större åtgärder genomföras då det har konstaterats att dagens åtgärder inte kommer att räcka. Gävle hamn har planer på att installera en vattenelektrolysör för vätgasproduktion av antingen Protonutbytesmembran (PEM) eller Alkalisk vattenelektrolys (AWE). Storleken på elektrolysören kommer vara ungefär 10 MW och har kapaciteten att producera 2000 ton fossilfri vätgas per år som kan försörja 100 tunga lastbilar. Dock är det i dagsläget billigare med fossil vätgasproduktion. Därför genomförs en litteraturstudie innehållande en beräkningsdel. Där syftet är att undersöka mängden biprodukter som produceras samt om de kan säljas inom andra områden för att göra förnyelsebar vätgas mer ekonomiskt konkurrenskraftig. Information för studien har hämtats från databaser, sökmotorer, företag, myndigheter och enskilda personer som ansetts relevanta för studien. Biprodukterna från 10 MW elektrolysören i Gävle hamn har jämförts med 1,5 MW och 17 MW elektrolysörer, sedan har även en känslighetsanalys utförts på elektrolysörerna. Potentialen att generera värme beror på typen av elektrolysör där AWE genererar 77 MWh restvärme per dygn och PEM genererar potentiellt 67 MWh restvärme per dygn. Vidare behöver AWE 64 kWh el för att producera 1 kg vätgas medan PEM behöver 66,5 kWh el per producerat kg vätgas. Intäkterna från restvärmeförsäljningen för AWE beräknades årligen till ungefär 7mnSEK och för PEM ungefär 6 mnSEK. För att elektrolysframställd syrgas ska kunna konkurrera med kryogent framställd syrgas bör inte priset övergå 108 SEK/ton. För 10 MW elektrolysören beräknas syrgasförsäljningen kunna inbringa omkring 1,1 mnSEK årligen både för AWE och PEM. Totala inkomsten för AWE blir drygt 8,1 mnSEK/år och 7,1 mnSEK/år för PEM. AWE processen är att föredra då den är mer ekonomiskt hållbar då inkomsten från biprodukterna är 12% högre än PEM på grund av högre produktion av syrgas samt större generering av restvärme.
350

Uso de subproductos de la industria agroalimentaria como fuente de fibra. Respuesta de los consumidores

Curutchet González, Ana 24 January 2022 (has links)
Tesis por compendio / [ES] La investigación de la presente Tesis doctoral busca estudiar la respuesta del consumidor a productos enriquecidos en fibra mediante la incorporación de subproductos de la industria alimentaria.Se estudió el interés de los consumidores uruguayos en diferentes mejoras nutricionales, el tipo de elaboración y cómo ha cambiado en los últimos diez años. Los resultados muestran que la respuesta de los consumidores es distinta dependiendo del tipo de queso. Solo en el queso untable, hay interés en la reducción de grasa. Respecto a los cambios con el tiempo, se observó para el queso semi-blando, un aumento en el interés por la elaboración artesanal. Se estudió el uso de distintos subproductos como ingredientes en el enriquecimiento en fibra de productos de consumo habitual. Se trabajó con el descarte de la producción de jugo de arándanos. Este se transformó en una harina y se incorporó a la formulación de galletas. Las expectativas de los consumidores al observar la etiqueta de esta galleta fueron tan buenas como una galleta sin fibra. Sin embargo, cuando la probaron sin tener información les gustó menos que la galleta sin fibra, pero al conocer que era rica en fibra aumentó su aceptabilidad ligeramente. Por lo tanto, aunque les interesan las galletas ricas en fibra, no están dispuestos a comprometer aspectos hedónicos por atributos saludables. El segundo subproducto estudiado fue el generado durante la producción de jugo de manzana. La pulpa que se transformó en harina, se usó para el enriquecimiento en fibra de un bizcochuelo. Se estudió la respuesta de los consumidores al bizcochuelo enriquecido en fibra en presencia o no de la etiqueta con información "fuente de fibra" y "con fibra de manzana", comparativamente con un producto comercial sin fibra. Se evaluó la aceptabilidad y los motivos por los que lo compraría o no. Los resultados indican que la aceptabilidad del bizcochuelo enriquecido en fibra aumentó significativamente con la información, lo que indica que además de la declaración "fuente de fibra", la indicación del origen de la fibra "con fibra de manzana" aumenta la aceptabilidad que el consumidor percibe de estos productos. Como tercer subproducto se utilizó el residuo de la industria cervecera, BSG (brewery spent grain). Se desarrollaron tres productos (pan, pasta y leche chocolatada) enriquecidos con fibra mediante la adición de BSG. Se evaluó el impacto del enriquecimiento de la fibra en las características sensoriales, la aceptabilidad y la intención de compra de los consumidores y luego en las emociones que el producto transmitía. La incorporación de fibra en los tres productos tuvo impacto significativo en las características sensoriales. Estas afectaron de forma distinta a la aceptabilidad y a la intención de compra dependiendo del producto. En lo que respecta a las emociones, se puede percibir una ambivalencia según los diferentes productos enriquecidos dependiendo si la fibra es percibida o no. Cuando la detectan se sienten más confiados en consumir el producto y con menos culpa. Por lo tanto, las características sensoriales que el consumidor percibe asociado a la fibra puede, en algunos productos, aumentar la intención de compra del consumidor y hacerle sentir mejor.Se estudió el efecto de la forma de comunicación del enriquecimiento de BSG en la respuesta del consumidor a hamburguesas de carne y si dependía de la marca comercial. Se consideraron tres marcas (una líder, una de bajo precio y una artesanal) y utilizando su empaque original se diseñaron tres etiquetas incluyendo diferente tipo de información y un símbolo representando sustentabilidad. La marca fue el único factor estudiado que afectó la intención de compra y sin embargo el tipo de información no tuvo efecto. Por todo lo obtenido podemos decir que es posible utilizar subproductos de la industria alimentaria como ingredientes para enriquecer nutricionalmente otros alimentos. / [CA] La investigació de la present Tesi doctoral busca estudiar la resposta del consumidor a productes enriquits en fibra per mitjà de la incorporació de subproductes de la indústria alimentaria.Se va estudiar l'interés dels consumidors uruguaians en diferents millores nutricionals, el tipus d'elaboració i com ha canviat en els últims deu anys. Els resultats mostren que la resposta dels consumidors és distinta depenent del tipus de formatge. Només en el formatge untable, hi ha interés en la reducció de greix. Respecte als canvis amb el temps, es va observar per al formatge semi-blando, un augment en l'interés per l'elaboració artesanal. Es va estudiar l'ús de distints subproductes com a ingredients en l'enriquiment en fibra de productes de consum habitual. Es va treballar amb el descart de la producció de suc de nabius. Este es va transformar en una farina i es va incorporar a la formulació de galletes. Les expectatives dels consumidors a l'observar l'etiqueta d'esta galleta van ser tan bones com una galleta sense fibra. No obstant això, quan la van provar sense tindre informació els va agradar menys que la galleta sense fibra, però al conéixer que era rica en fibra va augmentar la seua acceptabilitat lleugerament. Per tant, encara que els interessen les galletes riques en fibra, no estan disposats a comprometre aspectes hedònics per atributs saludables. El segon subproducte estudiat va ser el generat durant la producció de suc de poma. La polpa que es va transformar en farina, es va usar per a l'enriquiment en fibra d'un bizcochuelo. Es va estudiar la resposta dels consumidors al bizcochuelo enriquit en fibra en presència o no de l'etiqueta amb informació;"fuente de fibra"; "con fibra de manzana";, comparativament amb un producte comercial sense fibra. Es va avaluar l'acceptabilitat i els motius pels quals ho compraria o no. Els resultats indiquen que l'aceptab. Com a tercer subproducte es va utilitzar el residu de la indústria cervesera, BSG (brewery spent grauet) . Es van desenrotllar tres productes (pa, pasta i llet xocolatada) enriquits amb fibra per mitjà de l'addició de BSG. Es va avaluar l'impacte de l'enriquiment de la fibra en les característiques sensorials, l'acceptabilitat i la intenció de compra dels consumidors i després en les emocions que el producte transmetia. La incorporació de fibra en els tres productes va tindre impacte significatiu en les característiques sensorials. Estes van afectar de forma diferent de l'acceptabilitat i a la intenció de compra depenent del producte. Pel que fa a les emocions, es pot percebre una ambivalència segons els diferents productes enriquits depenent si la fibra és percebuda o no. Quan la detecten se senten més confiats a consumir el producte i amb menys culpa. Per tant, les característiques sensorials que el consumidor percep associat a la fibra pot, en alguns productes, augmentar la intenció de compra del consumidor i fer-li sentir mejor.Se va estudiar l'efecte de la forma de comunicació de l'enriquiment de BSG en la resposta del consumidor a hamburgueses de carn i si depenia de la marca comercial. Es van considerar tres marques (una líder, una de baix preu i una artesanal) i utilitzant el seu prestància original es van dissenyar tres etiquetes incloent diferent tipus d'informació i un símbol representant sustentabilidad. La marca va ser l'únic factor estudiat que va afectar la intenció de compra i no obstant això el tipus d'informació no va tindre efecte. Per tot allò que s'ha obtingut podem dir que és possible utilitzar subproductes de la indústria alimentària com a ingredients per a enriquir nutricionalment altres aliments. / [EN] The main focus of this work is studying the consumer's response to fibre enriched products by incorporating by-products from the food industry. The interest of Uruguayan consumers in different nutritional improvements and the method of preparation was studied. In the last decade, products with extra benefits have become much more common in the market, and the variation of this interest in recement years was also studied. The results show that the response of consumers is different depending on the type of cheese. Only in spreadable cheese, there is a certain degree of interest only in the reduction of fat. Regarding the changes over time, an increase in interest in artisanal production was observed for semi-soft cheese. Contrary to expectations, there was no increase in consumer interest for any of the nutritional improvements. The use of different by-products as ingredients for the fibre enrichment of products of habitual consumption was studied. The first by-product used was the residue from the blueberry juice production. This was transformed into a flour and incorporated into the cookie. The hedonic consumer expectations for this cookie when looking at the label were as good as a non-fibre cookie. However, when they tasted it without information, they liked it less than the non-enriched cookie, although knowing that it was rich in fibre increased its acceptability slightly. Therefore, while consumers are interested in high fibre cookies, they are not willing to compromise hedonic aspects for healthy attributes. The second by-product studied was the one generated during the production of apple juice. This pulp that was transformed into flour and used for the fibre enrichment of a sponge cake. The response of consumers to the fibre enriched sponge cake was studied with and without information on the label ("source of fibre" and "with apple fibre") in comparison with a commercial product. Product's acceptability were studied. The results show that the acceptability of the fibre enriched sponge cake increased significantly with the information, indicating that in addition to the claim "source of fibre", knowing the of origin of the fibre "with apple fibre" increases the acceptability that the consumer perceives. The third by-product used was the residue from the brewing industry, BSG (brewery spent grain). Three different products were developed (bread, pasta and chocolate milk) enriched with fibre by adding BSG. First, the impact of fibre enrichment on sensory characteristics, acceptability and purchase intention of consumers was evaluated. Finally, the effect of the products on the emotions of the consumers was studied. The incorporation of fibre in the three products had a significant impact on the sensory characteristics. However, these affected acceptability and purchase intention differently depending on the product. Regarding emotions, an ambivalence can be perceived in what is generated by the different enriched products depending on whether the fibre is perceived or not. When they detect it, they feel more confident in consuming the product and with less guilt. Therefore, the sensory characteristics that the consumer perceives associated with fibre can, in some products, not only increase the consumer's purchase intention but also make them feel better. The effect of the way to communicate the BSG enrichment on the consumer's response to meat burgers, and whether it depended on the commercial brand was studied. Three brands were considered (one leading, one low-priced and one artisanal) and using their original packaging, three labels were designed including different types of ways of conveying the information and a symbol representing sustainability. The brand was the only factor studied that affected purchase intention, and the way used to convey the information had no effect. In conclusion, it is possible to use by-products from the food industry as ingredients to nutritionally enrich other foods. / The financial support of Generalitat Valenciana (Project Prometeo 2017/189) and LATU, Uruguay for Arcia’s stay at IATA, are all gratefully acknowledged. / Curutchet González, A. (2021). Uso de subproductos de la industria agroalimentaria como fuente de fibra. Respuesta de los consumidores [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/180385 / Compendio

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