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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.
211

Internal residues of the narcotic organic chemicals in the Cladoceran, Daphnia magna

Pawlisz, Andrew V. January 1993 (has links)
No description available.
212

Limnetic Zooplankton Structure and The Impact of Invasion by an Exotic Cladoceran, Daphnia lumholtzi

Pasko, Susan R. 02 July 2009 (has links)
No description available.
213

Herbicides, Reservoirs, and Daphnia Reproduction: Is There a Cost to Male Production?

Stoeckel, James A. 03 August 2007 (has links)
No description available.
214

Effects of Ultraviolet Radiation (UVR) Induced DNA Damage and Other Ecological Determinants on <i>cryptosporidium Parvum</i>, <i>Giardia Lamblia</i>, and <i>Daphnia</i> spp. in Freshwater Ecosystems

Connelly, Sandra J. 29 November 2007 (has links)
No description available.
215

A Mechanistic Study Of Food Quality and Aqueous C60 Nanoparticles Impact On The Photo-induced Toxicity Of Fluoranthene To Daphnia Magna

Yang, Xinyu 27 July 2009 (has links)
No description available.
216

Development of an Acute Biotic Ligand Model for Ni Toxicity to Daphnia pulex in Soft Water: Effects of Ca, Mg, Na, K, Cl, pH and Dissolved Organic Matter

Kozlova, Tatiana A. 09 1900 (has links)
<p> In this study the influence of several water chemistry parameters on the toxicity of Ni to Daphnia pulex in soft water were tested. A reconstituted soft water (pH 7.8, hardness 31.5 mg/L CaCO3) was used as the basis for culture and testing. Daphnia pulex was chosen as a typical cladoceran, one which can be acclimated to very soft water. An understanding of the influence of water chemistry on Ni toxicity in soft water is relevant because metals have higher bioavailability in soft water. The 48h EC50 in the reconstituted soft water (RSW) was 974 μg/L (16 μM) dissolved Ni (95%CI 830- 1081 μg/L). The following factors were examined for their potential for modifying Ni toxicity: Ca, Mg, Na, K, Cl, pH (3 different approaches used) and natural organic matter (NOM, 2 sources tested). Both Ca and Mg protected against Ni toxicity and the relative effect was greater for Ca. Varying the concentrations of Na, Cl or K did not alter the toxicity of Ni. Tests at different pH showed that as pH increased, Ni toxicity decreased. When the test solution pH was adjusted with the organic buffer 3-morpholinepropanesulfonic acid, there was a clear correlation between increasing pH and increasing EC50. The pH tests using bicarbonate to adjust pH did not show this relationship as clearly. Both types of NOM showed a protective effect on Ni toxicity with Nordic Reservoir NOM having a 4 fold greater effect than that of Suwannee River NOM. This research illustrated that the effect of alterations in water chemistry were generally as predicted within the context of the biotic ligand model (BLM) approach. The data provide the information required to develop a BLM for the acute effects of Ni in soft water.</p> / Thesis / Master of Science (MSc)
217

Influence de la matière organique dissoute sur la spéciation et la biodisponibilité des métaux : cas de la Seine, un milieu sous forte pression urbaine / Role of dissolved organic matter to metal speciation and bioavailability : the case of the Seine river, one human-impacted system

Pernet-Coudrier, Benoît 04 December 2008 (has links)
Ce doctorat s’intègre dans le projet ANR BIOMET (JC05_59809) et a eu pour vocation d’améliorer les connaissances actuelles sur l’influence de la matière organique dissoute sur la spéciation et la biodisponibilité des métaux particulièrement dans le cas de système sous forte pression urbaine tel que la Seine. La compréhension de l’influence de la MOD sur la spéciation et la biodisponibilité des métaux suppose en outre que l’on connaisse précisément sa composition chimique ou plus exactement ses groupements fonctionnels. C’est pourquoi une partie de ces travaux est consacrée à l’extraction et la caractérisation de la matière organique dissoutes d’origine naturelle et urbaine. La caractérisation des fractions de MOD a été réalisée de manière originale par une approche multidimensionnelle à l’aide d’un véritable éventail de techniques analytiques (analyses élémentaires; isotopiques; fonctionnelles et moléculaires) permettant ainsi de mieux aborder l’influence de la MOD sur la spéciation et la biodisponibilité du cuivre et du plomb. Parallèlement à l’étude de caractérisation de la MOD, ce travail s’attache à mieux cerner le rôle de la MOD d’origine urbaine en particulier de la MOD hydrophile sur la spéciation et la biodisponibilité du cuivre et du plomb. Dans cet objectif, les techniques : potentiométrique à l’aide d’électrode ionique spécifique et la récente technique électrochimique AGNES ainsi que des biotests de toxicité aiguë (Daphnia magna) et de bioaccumulation (Fontinalis antipyretica) ont permis : - d’étudier la complexation du cuivre et du plomb par les fractions de MOD obtenues afin notamment de fournir des paramètres de complexations des MOD hydrophiles peu connues jusqu’à présent et ainsi mieux prédire le transport des métaux en milieu urbain. - d’évaluer le rôle protecteur de la MOD d’origine urbaine sur la biodisponibilité du cuivre. Les résultats ont montré que la MOD issue des effluents de station d’épuration et rejetée dans le milieu récepteur présente des caractéristiques originales à savoir un fort pourcentage de MOD hydrophile, c’est à dire une faible hydrophobicité et un degré d’aromaticité peu marqué soulignant le caractère peu réfractaire de cette MOD. En revanche une plus grande diversité fonctionnelle de la MOD d’origine urbaine par rapport à la MOD naturelle a été mise en évidence notamment par un taux de structures protéiques très important. Les résultats obtenus ici pour la première fois vis-à-vis des MOD hydrophiles d’origine urbaine ont montré une réactivité particulière vis-à-vis du cuivre. En effet les fractions HPI et plus généralement les fractions issues des effluents de station d’épuration ont montré une teneur en sites complexants plus élevée que ce qu’il avait été déjà observé pour des matières organiques naturelles. Les valeurs des constantes ne semblent pas varier d’une fraction à l’autre et assez peu suivant l’origine de la MOD. Le rôle particulier de l’azote dans la complexation du cuivre notamment sous la forme de groupements amines a été mis en évidence. Les approches utilisées pour évaluer la biodisponibilité du cuivre ont révélé pour l’ensemble des fractions de MOD un effet protecteur vis-à-vis du cuivre sur les organismes vivants. Néanmoins cet effet protecteur ne se trouve pas à la hauteur de celui pouvant être prédit par le modèle de l’ion libre principalement dû à une biodisponibilité de certains complexes organiques. Ceci peut être expliqué par l’important taux de structures protéiques dans ces MOD, les protéines étant connues pour jouer un rôle important dans les mécanismes de transports des métaux au sein des organismes. Par ailleurs, l’outil DGT (Diffusive gradient in thin films) a montré son efficacité pour évaluer la fraction biodisponible du cuivre / This thesis was carried out on the framework of the ANR BIOMET research project (JC05_59809). The main objectives were to improve the current knowledge on the influence of dissolved organic matter (DOM) on metal speciation and bioavailability in urban aquatic system. The understanding of the influence of DOM on trace metal speciation and bioavailability required that the chemical composition of DOM, more exactly its binding sites should be well understood. Therefore, one part of this research focused on the isolation and characterization of DOM. The characterization of DOM, with a multidimensional approach was realized with a lot of various techniques (such as elemental, isotopic, functional and molecular) that were of prime importance to better understand the influence of DOM on trace metal speciation and bioavailability. To accomplish these objectives, the techniques such as potentiometry with ionic selective electrode and the recent electroanalytical technique AGNES and bioassays such as a bioaccumulation test (Fontinalis antipyretica) and an acute toxicity test (Daphnia magna) were performed in order to: - study the copper and lead binding by isolated DOM fractions in order to give some binding parameters of hydrophilic DOM and to better predict the fate of the trace metal. - evaluate the protective role of urban DOM on copper bioavailability. Results showed some particular characteristics of DOM from wastewater effluent such as a high proportion of hydrophilic DOM, i.e. a low hydrophobicity and a low degree of aromaticity underlying the low refractory character of urban DOM. Nevertheless a higher content of various functional groups was determined in urban DOM than in natural DOM. A very high content of proteinaceous structures was particularly identified in urban DOM. Binding experiments revealed for the first time on urban hydrophilic DOM, a higher content of binding sites than in natural DOM and these sites are strongly correlated to amino groups. The values of binding constant seem to not vary according to the nature of the fraction or the origin. The different approaches used to evaluate copper bioavailability depicted a protective role of DOM to the organisms Daphnia magna and Fontinalis antipyretica. Nevertheless this protective effect is hardly explained by the free ion concentration due to a bioavailability of some organic complexes. This feature could be explain with the high content of proteinaceous structures in these DOM fractions, since proteins are well know to play an important role in the transport mechanisms of trace metals into the organisms. Moreover, the DGT device (diffusive gradient in thin films) shows a good efficiency to assess the bioavailable copper
218

Avaliação da qualidade da água e sedimento da sub-bacia do rio Corumbataí (SP) por meio de testes ecotoxicológicos / Water and sediment quality assessment of Corumbataí River (SP) using bioassays

Santos, Maria Alice Penna Firme dos 12 August 2008 (has links)
Foram realizados testes de toxicidade ao longo de dois anos, com amostras de água e sedimento do rio Corumbataí, entre Novembro de 2004 e Setembro de 2006, com o objetivo de avaliar a qualidade da água e do sedimento. Os testes de toxicidade aguda realizados com os organismos Chironomus xanthus, Daphnia magna, Hydra attenuata, Lactuca sativa e Pseudokirchneriella subcapitata indicaram variados graus de toxicidade nos diferentes pontos de coleta do rio Corumbataí, com maior ocorrência de toxicidade nos pontos de coleta mais próximos à foz do rio, principalmente devido à afluência do Ribeirão Claro. Todas as amostras de sedimento se mostraram mais tóxicas do que as amostras de água dos mesmos locais, para todos os organismos utilizados, em todas as coletas realizadas. Para todos os organismos, foram realizados testes de sensibilidade, com substância de referência (NaCl), mensalmente, a fim de garantir a qualidade dos cultivos em laboratório e dos bioensaios realizados, com resultados regulares e satisfatórios. Os efeitos produzidos pelas amostras ambientais sobre as sementes de alface (Lactuca sativa) foram bastante variáveis e irregulares, não possibilitando os cálculos de CI50. Decidiu-se por bem suspender a realização deste teste após um ano. Dentre todos os endpoints avaliados, os dos testes de Hydra attenuata e Pseudokirchneriella subcapitata se mostraram mais sensíveis, e o de Daphnia magna o menos sensível às amostras testadas. A avaliação da toxicidade através de efeitos subletais em H. attenuata se mostrou um bom parâmetro de avaliação das condições ambientais do rio Corumbataí, sendo um dos endpoints mais sensíveis utilizados. Outros testes de toxicidade foram realizados em algumas das oito coletas realizadas neste estudo, em caráter complementar: teste de toxicidade crônica com D. magna, teste de toxicidade LuminoTox, que utiliza sistemas enzimáticos vegetais, e o teste de genotoxicidade com Allium cepa, com o objetivo de avaliar suas sensibilidades e contribuições ao estudo. Estes bioensaios adicionaram informações a respeito dos níveis de poluição e toxicidade do rio Corumbataí, contribuindo com os bioensaios principais. Informações como parâmetros físicos e químicos, quantificação de elementos químicos e herbicidas ofereceram subsídios para a interpretação dos resultados obtidos com os testes de toxicidade. São apresentados também resultados das atividades referentes ao estágio de doutorado realizado no exterior (doutorado-sanduíche), no período de Setembro a Dezembro de 2007, na agência de proteção ambiental Environment Canada, no qual foi aplicado um teste de toxicidade com linhagens microbianas (MARA assay) em amostras de água e sedimento, juntamente com nanomateriais / Toxicity tests were conducted for two years with water and sediment samples from Corumbataí River, between November 2004 and September 2006, in order to assess the water and sediment quality. Acute toxicity tests conducted with Chironomus xanthus, Daphnia magna, Hydra attenuata, Lactuca sativa and Pseudokirchneriella subcapitata showed varying degrees of toxicity along the river course, with more toxic results in the sampling sites near the river mouth, due mainly to the inflow of Ribeirão Claro. All sediment samples were more toxic than the water samples (from the corresponding sites), for all test organisms, and for all samplings. Sensitivity tests were performed monthly, with NaCl as the reference toxicant, in order to guarantee both the laboratory culture quality and the bioassays conducted with these organisms. Results with NaCl were regular and satisfactory. The effects of the samples on lettuce seeds (L. sativa) were irregular, thus not allowing the estimative of IC50. It was decided to suspend the performance of this bioassay after one year of testing. Among all studied tests and endpoints, the tests with H. attenuata and P. subcapitata had the most sensitive endpoints, and the acute toxicity test with D. magna had the less sensitive one. Toxicity assessment of Corumbataí River based on Hydra sub-lethality endpoint was one of the most sensitive among the tested ones. Other bioassays were conducted at least once as part of this study, as a complementary assessment: the 21-day chronic toxicity test with D. magna, the LuminoTox bioassay, and the genotoxicity test with Allium cepa, in order to assess their sensitivity and contribution to the present study. These bioassays added information about the contamination levels and toxicity of Corumbataí River, contributing with the main bioassays performed. Data such as physical and chemical parameters, metals and herbicides determinations had a contribution to bioassay results interpretation. Results from a research project developed during a four-month stay (from September 2007 to December 2007) at Environment Canada Protection Agency are further described, regarding the application of the MARA bioassay, (conducted with 11 microbial strains), testing water and sediment samples, along with nanomaterials
219

Tratamento da água residuária de matadouro utilizando um sistema constituído de reatores com biofilme / Treatment of slaughterhouse wastewater using a system consisting of reactors with biofilm

Erlon Lopes Pereira 30 January 2014 (has links)
O aumento na produção de carne bovina aumentou a concentração e volume dos resíduos líquidos produzidos durante seu beneficiamento, conhecidos como água residuária de matadouros (ARMV). Isso vem estimulando o desenvolvimento de processos que operem em alta carga com alta eficiência para seu tratamento. Visto o exposto, objetivou-se avaliar um sistema de tratamento para a ARMV operando em condições anaeróbia/aeróbia/anóxica de forma conjugada visando a remoção de matéria orgânica, nutrientes e toxidade. As unidades que compunham o sistema estudado eram três reatores com biofilme denominados: Reator Anaeróbio Híbrido (RAH), Reator Aeróbio de Leito Móvel (MBBR) e Reator Anóxico com Biofilme (RAB). A ARMV in natura era coletada em um frigorífico e matadouro bovino do vale do Paraíba e caracterizada em termos físicos, químicos e toxicológicos a nível agudo e crônico. O experimento durou aproximadamente 370 dias, operando sob variações de carga orgânica. A coleta ao longo do sistema foi feita semanalmente e as amostras caracterizadas em termos físico-químicos e toxicológicos tanto a nível agudo quanto crônico. Nos reatores RAH, MBBR e RAB foram realizadas testes hidrodinâmicos em condições abiótico e biótico, respectivamente. Com os dados obtidos nas três fases estudadas foram levantados os parâmetros cinéticos de crescimento da biomassa dispersa, além da caracterização microbiológica da mesma e do biofilme. Os resultados obtidos com base na caracterização físico-química e toxicológica da ARMV, in natura, revelaram altas concentrações em toda série de sólidos, de ácidos voláteis totais, alcalinidades, macro e micronutrientes, matéria orgânica em termos de DBO520°C e DQO nas formas total, solúvel e particulada e também de COD. Apresentou-se como um efluente extremamente tóxico a nível agudo para os organismos, bactérias P. putida e E. coli e microcrustaceo D. similis, e extremamente tóxico a nível crônico para os organismos, microcrustaceios C. silvestri e C. dúbia, bactérias E. coli e P putida e alga P. subcaptata. Com base nos testes toxicológicos, concluiu-se que os microcrustaceos e algas foram mais sensíveis as toxinas da ARM testada que as bactérias. O reator RAH operando sob choques orgânicos demonstrou ótimo desempenho operacional. As cargas orgânicas (COV) aplicadas ao RAH foram 608,9; 3.030,4 e 9.581,5 mg L-1 d-1 em termos de DQO para as fases I, II e III, estatisticamente diferente entre si. Apresentando para as três fases eficiências estatisticamente iguais. O reator MBBR operando sob choques orgânicos demonstrou ótimo desempenho operacional. As cargas orgânicas (COV) aplicadas ao MBBR foram 286,5; 2085,2 e 3889,6 mg L-1 d-1 em termos de DQO para as fases I, II e III, estatisticamente diferente entre si. Apresentando para as fases I, II e III eficiências de 76,9%; 60% e 81%, respectivamente, e estatisticamente iguais. Conclui-se com a pesquisa realizada que os reatores RAH e MBBR foram capazes de absorver choques orgânicos e hidráulicos submetidos a biomassa mantendo-se em altos valores de eficiência. O reator MBBR também apresentou bom desempenho no processo de nitrificação com eficiências de 61,2%; 68,1%; 50,7% para as fases I, II e III, respectivamente. A concentração média de OD de 3 mg L-1 mantida no MBBR apresentou-se acima do suficiente. O reator RAB operando sob choques orgânicos demonstrou ótimo desempenho operacional. As cargas orgânicas (COV) aplicadas ao RAB foram 194,9; 1769,1 e 2230,6 mg L-1 d-1 em termos de DQO para as fases I, II e III, estatisticamente diferente entre si. As fases I, II e III apresentaram eficiências de 70,7%; 46,4% e 69,8%, respectivamente, e estatisticamente, iguais entre as fases I e III. Em termos de toxidade, os parâmetros estudados nas fases I e II, mostraram-se ideais para remoção de toxidade, sendo que no final de ambas a ARM tratada apresentou-se livre de toxidade a nível agudo e crônico. Os reatores RAH, MBBR e RAB demonstraram ótimo desempenho hidrodinâmico e cinético. Concluiu-se que o sistema anaeróbio/aeróbio/anóxico estudado foi eficiente no tratamento da ARMV, aliando condições de fácil monitoramento, rapidez no processo e ótimo desempenho. / Development in bovine meat production has increased volume and concentration of liquid residues produced during their improvement, known as slaughterhouses wastewaters (SW). This fact has been stimulating the develpment of processes operating in highly charge and efficience for their treatment. As seen, we focused to develop a treatment system for the SW operating in a anaerobic/aerobic/anoxic condition in a conjugated form, aiming the remotion of organic matter, nutrients and toxicity. The units evolving the studied system were three biofilms reators named: Anaerobic Hibrid Reactor (AHR), Moving Bed Biofilm Reactors (MBBR), and Anoxic Biofilm Reactor (AnBR). The SW in natura was collected in the slaughterhouse of the Paraíba Valley, and were characterized in physical, chemical and toxically in a highly sharp and cronically levels. The experiment has lasted for 370 days, operating under organic load rate (OLR). The withdraws along the system were done weekly and the samples were characterized in physical-chemical and toxicological terms and in both sharp and cronical ways. Hidrodinamic tests were realized in reactors AHR, MBBR and AnBR in abiotic and biotic condictions, repectivelly. With the data obtained in the three studied phases, knetics parameters were collected for the dispersal biomass, besides its biofilm and biomass characterization. The results, based on SW physico - chemical and toxicological characterization, showed high concentrations in all solids series, in total volatic acids, alcalinity, macro and micro nutrients, organic matter in terms of BOD520°C and COD in their solute and particulate forms and also in DOC. It was presented as highly toxix effluent in a sharp level for organisms, bacteria P. putida ans E. coli, and D. similis microcrustacean. And extremely toxic to organisms chronic C. silvestri and C. dúbia microceustacean and P. subcaptata algae. According with toxicological tests it was concluded that the microcrustaceos and a algae were more sensitive to the SSW toxines than bacteria. The AHR reator operating under organic shocks showed excelent operational development. The OLR applied to the AHR were 608.9; 3,030.4 and 9,581.5 mg L-1 d-1 in terms of COD for the phases I, II, III, statiscally different among it, showing for the three phases scores of 76,9%; 60% and 81%, respectivelly, and the same, statistically speaking. We may conclude with this research that the AHR and AMBR reators were capable to absorb hidraulic and organic shocks submitted to biomass keeping high levels of efficiency. The MBBR reator has shown also a good performance in nitrification process, scoring 61.2%; 68.1%; 50.7% in effectiveness for phases I, II and III, respectively. The average DO concentration of 3 mg L-1 maintained in MBBR showed over sufficience. The AnBR reator under organic shocks showed highly operational performance. The OLR applied to AnBR were 194.9; 1,769.1 e 2,230.6 mg L-1 d-1 in terms of COD for the phases I, II, III statistically different among them. The phases I, II, III presented efficiences of 70.7%; 46.4% and 69.8%, respectively, and statiscally the same between phases I and III. In terms of toxicity, the studied parameters in phases I and II showed to be ideal to remove the toxicity from both sharp and chronical levels. The reators AHR, MBBR and AnBR showed excelent hidraulic and kinetic performances. We may conclude that the studied anaerobic/aerobic/ anoxic system was efficient in the treatment of SW, joining, easy feasible conditions, velocity in processing and high performance.
220

Tratamento da água residuária de matadouro utilizando um sistema constituído de reatores com biofilme / Treatment of slaughterhouse wastewater using a system consisting of reactors with biofilm

Pereira, Erlon Lopes 30 January 2014 (has links)
O aumento na produção de carne bovina aumentou a concentração e volume dos resíduos líquidos produzidos durante seu beneficiamento, conhecidos como água residuária de matadouros (ARMV). Isso vem estimulando o desenvolvimento de processos que operem em alta carga com alta eficiência para seu tratamento. Visto o exposto, objetivou-se avaliar um sistema de tratamento para a ARMV operando em condições anaeróbia/aeróbia/anóxica de forma conjugada visando a remoção de matéria orgânica, nutrientes e toxidade. As unidades que compunham o sistema estudado eram três reatores com biofilme denominados: Reator Anaeróbio Híbrido (RAH), Reator Aeróbio de Leito Móvel (MBBR) e Reator Anóxico com Biofilme (RAB). A ARMV in natura era coletada em um frigorífico e matadouro bovino do vale do Paraíba e caracterizada em termos físicos, químicos e toxicológicos a nível agudo e crônico. O experimento durou aproximadamente 370 dias, operando sob variações de carga orgânica. A coleta ao longo do sistema foi feita semanalmente e as amostras caracterizadas em termos físico-químicos e toxicológicos tanto a nível agudo quanto crônico. Nos reatores RAH, MBBR e RAB foram realizadas testes hidrodinâmicos em condições abiótico e biótico, respectivamente. Com os dados obtidos nas três fases estudadas foram levantados os parâmetros cinéticos de crescimento da biomassa dispersa, além da caracterização microbiológica da mesma e do biofilme. Os resultados obtidos com base na caracterização físico-química e toxicológica da ARMV, in natura, revelaram altas concentrações em toda série de sólidos, de ácidos voláteis totais, alcalinidades, macro e micronutrientes, matéria orgânica em termos de DBO520°C e DQO nas formas total, solúvel e particulada e também de COD. Apresentou-se como um efluente extremamente tóxico a nível agudo para os organismos, bactérias P. putida e E. coli e microcrustaceo D. similis, e extremamente tóxico a nível crônico para os organismos, microcrustaceios C. silvestri e C. dúbia, bactérias E. coli e P putida e alga P. subcaptata. Com base nos testes toxicológicos, concluiu-se que os microcrustaceos e algas foram mais sensíveis as toxinas da ARM testada que as bactérias. O reator RAH operando sob choques orgânicos demonstrou ótimo desempenho operacional. As cargas orgânicas (COV) aplicadas ao RAH foram 608,9; 3.030,4 e 9.581,5 mg L-1 d-1 em termos de DQO para as fases I, II e III, estatisticamente diferente entre si. Apresentando para as três fases eficiências estatisticamente iguais. O reator MBBR operando sob choques orgânicos demonstrou ótimo desempenho operacional. As cargas orgânicas (COV) aplicadas ao MBBR foram 286,5; 2085,2 e 3889,6 mg L-1 d-1 em termos de DQO para as fases I, II e III, estatisticamente diferente entre si. Apresentando para as fases I, II e III eficiências de 76,9%; 60% e 81%, respectivamente, e estatisticamente iguais. Conclui-se com a pesquisa realizada que os reatores RAH e MBBR foram capazes de absorver choques orgânicos e hidráulicos submetidos a biomassa mantendo-se em altos valores de eficiência. O reator MBBR também apresentou bom desempenho no processo de nitrificação com eficiências de 61,2%; 68,1%; 50,7% para as fases I, II e III, respectivamente. A concentração média de OD de 3 mg L-1 mantida no MBBR apresentou-se acima do suficiente. O reator RAB operando sob choques orgânicos demonstrou ótimo desempenho operacional. As cargas orgânicas (COV) aplicadas ao RAB foram 194,9; 1769,1 e 2230,6 mg L-1 d-1 em termos de DQO para as fases I, II e III, estatisticamente diferente entre si. As fases I, II e III apresentaram eficiências de 70,7%; 46,4% e 69,8%, respectivamente, e estatisticamente, iguais entre as fases I e III. Em termos de toxidade, os parâmetros estudados nas fases I e II, mostraram-se ideais para remoção de toxidade, sendo que no final de ambas a ARM tratada apresentou-se livre de toxidade a nível agudo e crônico. Os reatores RAH, MBBR e RAB demonstraram ótimo desempenho hidrodinâmico e cinético. Concluiu-se que o sistema anaeróbio/aeróbio/anóxico estudado foi eficiente no tratamento da ARMV, aliando condições de fácil monitoramento, rapidez no processo e ótimo desempenho. / Development in bovine meat production has increased volume and concentration of liquid residues produced during their improvement, known as slaughterhouses wastewaters (SW). This fact has been stimulating the develpment of processes operating in highly charge and efficience for their treatment. As seen, we focused to develop a treatment system for the SW operating in a anaerobic/aerobic/anoxic condition in a conjugated form, aiming the remotion of organic matter, nutrients and toxicity. The units evolving the studied system were three biofilms reators named: Anaerobic Hibrid Reactor (AHR), Moving Bed Biofilm Reactors (MBBR), and Anoxic Biofilm Reactor (AnBR). The SW in natura was collected in the slaughterhouse of the Paraíba Valley, and were characterized in physical, chemical and toxically in a highly sharp and cronically levels. The experiment has lasted for 370 days, operating under organic load rate (OLR). The withdraws along the system were done weekly and the samples were characterized in physical-chemical and toxicological terms and in both sharp and cronical ways. Hidrodinamic tests were realized in reactors AHR, MBBR and AnBR in abiotic and biotic condictions, repectivelly. With the data obtained in the three studied phases, knetics parameters were collected for the dispersal biomass, besides its biofilm and biomass characterization. The results, based on SW physico - chemical and toxicological characterization, showed high concentrations in all solids series, in total volatic acids, alcalinity, macro and micro nutrients, organic matter in terms of BOD520°C and COD in their solute and particulate forms and also in DOC. It was presented as highly toxix effluent in a sharp level for organisms, bacteria P. putida ans E. coli, and D. similis microcrustacean. And extremely toxic to organisms chronic C. silvestri and C. dúbia microceustacean and P. subcaptata algae. According with toxicological tests it was concluded that the microcrustaceos and a algae were more sensitive to the SSW toxines than bacteria. The AHR reator operating under organic shocks showed excelent operational development. The OLR applied to the AHR were 608.9; 3,030.4 and 9,581.5 mg L-1 d-1 in terms of COD for the phases I, II, III, statiscally different among it, showing for the three phases scores of 76,9%; 60% and 81%, respectivelly, and the same, statistically speaking. We may conclude with this research that the AHR and AMBR reators were capable to absorb hidraulic and organic shocks submitted to biomass keeping high levels of efficiency. The MBBR reator has shown also a good performance in nitrification process, scoring 61.2%; 68.1%; 50.7% in effectiveness for phases I, II and III, respectively. The average DO concentration of 3 mg L-1 maintained in MBBR showed over sufficience. The AnBR reator under organic shocks showed highly operational performance. The OLR applied to AnBR were 194.9; 1,769.1 e 2,230.6 mg L-1 d-1 in terms of COD for the phases I, II, III statistically different among them. The phases I, II, III presented efficiences of 70.7%; 46.4% and 69.8%, respectively, and statiscally the same between phases I and III. In terms of toxicity, the studied parameters in phases I and II showed to be ideal to remove the toxicity from both sharp and chronical levels. The reators AHR, MBBR and AnBR showed excelent hidraulic and kinetic performances. We may conclude that the studied anaerobic/aerobic/ anoxic system was efficient in the treatment of SW, joining, easy feasible conditions, velocity in processing and high performance.

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