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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.
1

Removal of Estrogens at Full and Pilot Scale Livestock Manure Treatment Systems

Zhao, Zunyang 06 February 2008 (has links)
Three experiments were conducted to 1) develop appropriate methods for livestock manure estrogen analysis; 2) determine estrogen removal in different manure treatment systems; and 3) determine estrogen removal from dairy manure in pilot scale reactors. In Experiment I, the recoveries of 17à -estradiol (E2) and estriol (E3) were evaluated in double distilled water and dairy manure after a base extraction and analysis of estrogens by enzyme-linked immunoassay (ELISA) and yeast estrogen screen (YES) assay. The recoveries of E2 were 104% (ELISA) and 97% (YES) in double distilled water. 112% of E2 and 79% of E3 in flushed dairy manure and 118% of E2 in anaerobic digester effluent were recovered with ELISA. 67% and 140% of E2 in flushed manure and anaerobic digester effluent, respectively, were recovered with YES assay. In Experiment II, samples were collected from a full-scale manure handling system incorporating separation and aeration (Separation/Aeration), an anaerobic digester receiving dairy manure (Anaerobic Digester), and four conventional dairy and swine manure storages. 70% of E2 (230 vs. 769 μg/cow/day) and 86% of E3 (78 vs. 552 μg/cow/day) mass were removed from the Separation/Aeration system when the effluent was compared to the influent; the ratio of E2 to total estrogenicity (E2-eq) averaged 76%. In the Anaerobic Digester, 38% of E2 (592 vs. 954 μg/cow/day) and 30% of E3 (338 vs. 483 μg/cow/day) mass were removed; E2 contributed more to E2-eq in the influent than in the effluent (43 vs. 26%). There was no significant difference for E2-eq (431 vs. 284 ng/g of total solids) and E2 (248 vs. 73 ng/g of total solids) concentrations between barn and pti in conventional dairy manure storages; E2 contributed more to E2-eq in barn manure than in pit manure (54 vs. 30%). In swine manure storages, both E2-eq (2852 vs. 1551 vs. 148 ng/g of total solids) and E2 (1933 vs. 808 vs. 89 ng/g of total solids) concentrations decreased (barn vs. primary lagoon vs. secondary lagoon; no significance analysis); the change of E2 ratio to E2-eq was not consistent between barn and lagoon manures between farms. In Experiment III, samples were collected from six pilot scale reactors: two aerated reactors (60% and 100% aeration; AER60 and AER 100), a nitrifying/denitrifying reactor (NDN), an enhanced biological phosphorus removal reactor (EBPR), an anaerobic digester (AD), and a nitrifying reactor (NI) following AD. The influent had higher mass of E2 and E2-eq than the effluent with all reactors. Estrogen removal efficiencies were expressed in two ways: % and %/aerobic hour (or hour) of the influent mass. Higher ammonia nitrogen removing reactors had higher E2 and E2-eq removal in %, higher E2 removal in %/aerobic hour, and the same E2-eq removal in %/aerobic hour compared to those with lower ammonia nitrogen removal. Estrogen removal efficiencies (both in % and %/aerobic hour) were similar in nitrifying and denitrifying reactors. Reactors with aeration supported greater estrogen removal than those without. Reactors with influent anaerobic digestion pretreatment had the same E2 and E2-eq removal in % but higher E2 and E2-eq removal in %/aerobic hour compared to those without. In conclusion, the aerobic treatment system removed more estrogens than the anaerobic one, which means aerobic conditions support more estrogen degradation than anaerobic conditions. The change of the ratios of E2 to E2-eq varied in different livestock manure treatment systems, which reflected different removal rates of E2 and other estrogenic compounds. The pilot scale reactors significantly removed E2 and E2-eq in dairy manure. Ammonia nitrogen removal rates and aeration are the two main factors influencing E2 and E2-eq removal. / Ph. D.
2

Compostage et vermicompostage des effluents d'elevage : une alternative durable pour le recyclage des dechets d'origine animale / Composting and vermicomposting of livestock manure : a sustainable alternative to recycle animal wastes.

Faverial, Julie 26 July 2016 (has links)
En Guadeloupe, l'utilisation de composts se heurte à de nombreux freins, aussi bien en termes de leur qualité qu’en termes d’un manque de plateformes de compostage à grande échelle et de proximité. Des études récentes ont montré que la qualité des composts locaux était plus faible qu’en milieu tempéré, ce qui constituerait un verrou majeur à l’adoption de la pratique et l’utilisation des composts industriels locaux. Pourtant, les objectifs de valorisation des déchets organiques fixés par les instances publiques sont ambitieux et le gisement local, bien que diffus et actuellement mal géré ou négligé, présenterait un réel intérêt pour la profession agricole à être orienté vers la valorisation biologique telle que le compostage. Dans ce contexte, l’objectif de ce travail était d'évaluer la qualité des composts élaborés en milieu tropical et d'apporter des éléments factuels pour son amélioration et, plus spécifiquement, d’apporter de l’information sur les potentialités agronomiques du compostage des effluents d’élevage en Guadeloupe, présentant ainsi le compostage comme une alternative durable pour le recyclage des déchets d’origine animale.Une méta-analyse de 442 composts d'origine diverse, la première réalisée sur le sujet, nous a permis de démontrer que les composts produits en milieu tropical présentent des teneurs en carbone, azote, potassium et fraction soluble de la matière organique plus faibles que celles des composts produits en milieu tempéré, et que cela pourrait notamment être dû à l’influence des conditions climatiques lors du compostage. En revanche, nous avons pu mettre en évidence que certaines matières premières permettaient l’obtention de composts de meilleure qualité quelque soit le climat considéré, il s’agissait entre autres des effluents d’élevage.Les résultats issus d'une série d’expérimentations menée sur la production de composts d’effluents d’élevage avec co-compostage et vermicompostage ont été traités avec une approche méthodologique innovante dans ce domaine, les Réseaux Bayésiens. L’évaluation réalisée sur le co-compostage effluents/déchets verts nous a permis d’identifier l’"effet de concentration" du carbone et de la lignine, comme celui qui définit la qualité des composts en termes de quantité et de stabilité de la matière organique. En revanche, dans le cas des nutriments, seule la qualité des matières premières a été identifiée comme le facteur déterminant de la qualité des produits finaux. Ces résultats nous ont amené à considérer les effluents d’élevage de bovin comme la matière première la plus efficace pour produire des co-composts de qualité satisfaisante, répondant à la problématique d’usure de la matière organique des sols guadeloupéens et permettant de satisfaire les attentes de la profession agricole.De plus des expérimentations réalisées sur les composts domestiques ont montré que la gamme analysée présentait une variabilité trop importante pour être considérée comme acceptable par la profession agricole. Le compostage domestique peut permettre de produire des composts de bonne qualité agronomique à utiliser à la petite échelle des jardins particuliers et des jardins créoles. / In Guadeloupe, the practice of composting faces many obstacles and preconceptions both in terms of quality and in terms of lack of large-scale composting plants as well as local composting facilities. Recent studies have shown that the quality of local composts was lower compared to those from temperate regions. This constitutes an important constraint for the adoption of the former by farmers. However, organic waste recovery targets set by the government are ambitious and local resources, although diffused and currently poorly managed or neglected would be of real interest for the farming profession by being directed towards organic recycling such as composting. In this context, the aim of this thesis was to evaluate the quality of compost produced in the tropics, provide factual elements for improvement and, more specifically, to provide information on the agronomic potential of composting livestock manure in Guadeloupe, presenting composting as a sustainable alternative for the recycling of animal waste.A meta-analysis of 442 composts from various sources, the first one to be conducted on the subject enabled us to demonstrate that composts produced in the tropics present lower contents of carbon, nitrogen, potassium and soluble fraction of organic matter than those produced in temperate environments. This could especially be due to the influence of climatic conditions during composting. However, we were able to show that some raw materials allow better quality composts whatever the considered climate, especially the case of livestock manure.A series of experiments conducted on the production of livestock manure composts with co-composting and vermicomposting were treated with an innovative methodological approach in this field, the Bayesian Networks. The evaluation carried out on co-composting has allowed us to identify that the "concentration effect" was the main factor affecting compost quality in terms of amount and stability of organic matter. While in the case of nutrients, only the quality of raw materials has been identified as the determining factor affecting the quality of the end products. These results led us to consider manure, mainly cattle manure, as the most efficient feedstock for producing satisfactory quality composts, meeting the needs of loss of soil organic matter in Guadeloupe and the needs of the farming profession.Further experiments performed on household composts showed that their quality exhibited a too important variability to be considered acceptable by farmers. Our results indicate that household composts could be suitable for use in small-scale private gardens and Creole gardens.

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