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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.
111

Nutrient sources and dynamics in the Parafield stormwater harvesting facility and implication to water quality control.

Kim, Young-Kil. January 2010 (has links)
The quantity of stormwater runoff from the city of Adelaide almost matches the demand for drinking water. It therefore becomes increasingly important as an alternative source for water supply. This research focused at the Parafield Stormwater Harvesting Facility near Adelaide in order to better understand: (1) nutrient dynamics between the water column, sediments and plant community, (2) allochthonous and autochthonous sources of nutrients and (3) nutrient retention capacity of the reed bed. A weekly monitoring programme for the physical and chemical parameters of the water column, sediment and plant community was carried out over three years for specific locations within the reed bed. Ordination and clustering of the time series data revealed distinctive seasonal and spatial nutrient patterns. The concentrations for total nitrogen (TN) showed high concentrations for the summer period (1.04 to 1.86 mg/L) and low concentration for the winter season (0.25 to 0.46 mg/L). For the other nitrogen fractions in form of nitrate (NO₃⁻) and ammonium (NH₄⁺) the seasonal patterns were different to that of TN. In NO₃⁻ the concentrations were high during the summer and winter seasons and NH₄⁺ showed high concentration during the spring. The seasonality for total phosphorus (TP) showed high concentration for the spring period (0.049 to 0.163 mg/L) and low concentration for the other seasons (0.01 to 0.019 mg/L). A similar pattern has been observed for phosphate (PO₄³ ⁻) as well. The dissolved organic carbon (DOC) concentrations showed high concentrations during the summer period (21.36 to 31.64 mg/L) and low concentration during the winter seasons (5.48 to 7.14 mg/L). The seasonal pattern for the nutrient contents of the plant community showed highest concentrations during summer (5.5 to 34.2 gTN/kg) and lowest concentrations in winter (0.2 to 7.7 gTN/kg). Nutrient concentrations in the sediments were highest during the non-growing seasons (autumn and winter). This result indicated that the function of sediments changes seasonally from being a sink during the non-growing season by accumulating both allochthonous and autochthonous nutrients in the rainy season, and becoming a source during the growing seasons due to nutrient release from anaerobic sediments supporting the growth of the macrophyte community. Overall the function of sediment in reed bed pond of the Stormwater Harvesting Facility was to be a source of nutrients and therefore no accumulation of nutrients occurred during the study period. The research has demonstrated that the reed bed currently performs as a reasonable nutrient retention system with following nutrient removal rates: 0.85 mg TN /m²/day, 0.79 mg NO₃⁻ /m²/day, 0.28 mg NH₄⁺/m²/day, 0.05 mg TP /m²/day, 0.04 mg PO₄³ ⁻ /m²/day, and 5.75 mg DOC /m²/day. Seasonal difference in the water retention time showed that the for most of the nutrients the removal performance was most effective during autumn and winter with the exception of the removal performance of P forms, which most effective during spring and summer. For TN, NO₃⁻ and DOC the RE was most efficient at a residence time > 15days, for TP and PO₄³ ⁻ it is 5-10 days and for NH₄⁺ it is <;5days. Time–series modelling of the monitoring data resulted in rule-based prediction models for the different nutrients. Sensitivity analyses of the models revealed key driving variables for the nutrient dynamics of the reed bed. The prediction results revealed that the DO was the key driving variable influencing the nutrient concentrations in the water column and therefore to improve the water quality of the treatment water DO levels have to maintained above the threshold of 4 mg/L. Beside DO other key driving variables were turbidity, ORP and the nutrient levels from the previous site. Therefore the control of these parameters would be the start to develop a management plan for best-practice management in terms of water quality at the Parafield Stormwater Harvesting Facility. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1458926 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Science, 2010
112

Optimisation du traitement de l'azote et du phosphore des eaux usées domestiques adapté aux filtres plantés de roseaux / Optimization of nitrogen and phosphorus removal in constructed wetland

Prigent, Stephane 19 October 2012 (has links)
Le rejet des nutriments (phosphates et nitrates) issues des eaux usées domestiques entraînent la dégradation des écosystèmes (74 % du territoire français concerné en 2006). Compte tenu de la situation, l’Etat français a promulgué la Loi sur l’Eau et les Milieux Aquatiques le 30décembre 2006 qui vise à atteindre le « bon état écologique des eaux et des milieux aquatiques » d’ici 2015. Cette notion bien que difficilement intégrable a généré des normes plus strictes pour les stations d’épuration en termes de rejet de nutriments vers le milieu récepteur (jusque 15 mg NTOT.L-1 et 2 mg PTOT.L-1). Depuis la fin des années 1990, la technologie des filtres plantés de roseaux (FPR) est de plus en plus employée(> 2500 unités en 2012) pour le traitement des eaux usées domestiques des petites collectivités inférieures à 2000 Equivalent-Habitants. Cependant, des limites de traitement existent sur les concentrations résiduelles en azote (rejet de 70-80 mg NTOT.L-1) et en phosphore (rejet> 10 mg PTOT.L-1), en vue de répondre à la réglementation future. Ce travail a eu pour objectif de mettre en oeuvre des améliorations telles que la recirculation sur un étage de traitement pour le traitement de l’azote d’une part et l’emploi de matériaux réactifs pour piéger le phosphore d’autre part. La démarche scientifique expérimentale déployée a consisté à suivre des pilotes sur site réel et en laboratoire pendant 2 années. Le suivi des performances épuratoires et hydrauliques a été réalisé au cours du temps. Pour l’azote, 2 FPR (2,5 m²) garnis de schiste expansé (Mayennite®) ont été alimentés en effluent brut. L’effet de la hauteur de saturation en eau dans la partie drainante ainsi que l’effet de la recirculation ont été étudiés. Les résultats obtenus ont montré : une couche saturée à 38 % (rapporté à la hauteur totale) et un ratio de recirculation de 100 % permettent une meilleure élimination de la matière particulaire-carbonée (Arrêté du22 juin 2007) et de l’azote (< 20 mg NTK.L-1 ; < 45 mgNTOT.L-1). Deux laitiers de four à arc électrique ont été sélectionnés pour le traitement du phosphore. Ceux-ci ont été mis en œuvre dans 5 colonnes (6 L) en laboratoire alimentées en effluent synthétique en phosphore puis secondaire et dans 4 filtres réactifs pilote (0,3 m² ; 34 L) à flux horizontal sous surfacique alimentés en effluent secondaire. Il ressort de ces expériences: (i) des disparités existent entre les deux échelles en termes de performances (< 2 mg P.L-1 pendant 20 mois en colonne et variation saisonnière des performances en pilote) et mécanismes épuratoires (adsorption/précipitation P-Caen colonne ; P-Ca + P-Fe en pilote), (ii) l’augmentation de la température (> 15 °C) et/ou du temps de séjour (48h et plus) améliore la cinétique d’élimination du phosphore à échelle pilote et (iii) l’implantation d’un filtre réactif garni de laitier de four à arc électrique est limité par le degré de traitement souhaité et la distance du futur chantier (coût du transport). / Nutrient (phosphorus and nitrogen) discharges from wastewater lead to water quality degradation (74 % of the total French territory in 2006). According to the actual situation, the French government has adopted a Water Framework on December 30, 2006 to achieve a“good ecological status of water” in 2015. Therefore,more stringent standards on nutrients removal for raw wastewater treatment plants are expected (down to 15mg TN.L-1 and 2 mg TP.L-1). However, standards actually remain under the responsibility of departmental authorities according to the water quality of the receiving environment. Since 1990s, Vertical Flow Constructed Wetlands(VFCWs) have been more and more popular in treating raw domestic wastewater for small collectivities of less than 2000 person equivalent (> 2500 units in 2012). However, nitrogen and phosphorus removal are limited in VFCWs (70-80 mg TN.L-1; > 10 mg TP.L-1) according to the new legislation. The aim of this work was on the one hand to implement a recirculation of treated effluent on a VFCW for better nitrogen removal and on the other to use reactive materials to improve phosphorus removal. The experimental scientific approach consisted in monitoring both laboratory and field pilot scale systems under process conditions during 2 years. Treatment and hydraulic performances were monitored over time. Two VFCWs (2,5 m²) filled with expanded schist (Mayennite®) were fed with raw domestic wastewater. The effect of a saturated layer and of the recirculation of treated effluent were studied. Results showed that 38 % of a saturated layer and 100 % of recirculation enabled to improve nitrogen treatment performances (< 20 mgTKN.L-1; < 45 mg TN.L-1) and to meet the French standard D4. Electric arc furnace slags were selected as reactive materials to improve phosphorus treatment performance of the VFCWs in laboratory and field pilot scale systems. Five laboratory-scale column experiments (6L) were fed with a phosphorus synthetic effluent then with a secondary effluent. Four horizontal subsurface flow active filters (0,3 m²; 34 L) were fed with a secondary effluent. The main results showed : (i)differences exist between laboratory and pilot scale regarding treatment performance (< 2 mg P.L-1 during20 months in the laboratory ; seasonal variations at pilot scale) and removal mechanisms (adsorption/precipitation Ca-P in laboratory ; Ca-P + Fe-P at pilot scale), (ii) an increase of temperature (> 15°C) and/or hydraulic retention time (more than 2 days) improved the kinetics of phosphorus removal at pilot scale, (iii) the active filter implementing is limited by the discharge standard required (> 3 mg PTOT.L-1) and the distance to the steel factory (transport costs).
113

Estudo comparativo de leitos percoladores e banhados construídos de fluxo vertical aplicados à remoção de fósforo em esgoto sanitário

Leal, Felipe Kruger January 2009 (has links)
A presente pesquisa avaliou duas alternativas para a remoção de fósforo em esgoto sanitário: uso de filtros percoladores com adição de material com potencial de ligação de fósforo e uso de banhados construídos com macrófitas com potencial assimilação de fósforo. Estas tecnologias são apropriadas para pequenas comunidades ou residências unifamiliares e também podem ser utilizadas como etapa no tratamento dos esgotos. Estes sistemas apresentam remoção satisfatória de matéria orgânica e nitrogênio amoniacal, contudo apresentam diminuta eficiência de remoção de fósforo e nitrato. Na presente pesquisa foram estudadas duas técnicas para aumentar a remoção de fósforo: utilização de materiais com potencial de remoção de fósforo nos filtros percoladores, e plantas com alta capacidade de assimilação de fósforo nos banhados construídos. Os materiais adicionados aos leitos percoladores com potencial de remoção de fósforo foram: Cavaco de Usinagem e Escória de Aciaria Elétrica. As frações de materiais adicionados foram: 10%, 20% e 40% em peso em relação ao material suporte. As plantas utilizadas foram a Luziola peruviana, a qual apresenta em sua constituição alta concentração de fósforo e a Typha latifolia, já amplamente utilizada em banhados construídos. Os materiais utilizados como meios suportes foram brita e areia. A adição de materiais com potencial remoção de fósforo auxiliou na remoção do nutriente, a qual foi mais significativa nos leitos contendo Cavaco de Usinagem. Não foi observada diferença de remoção de fósforo para as diferentes frações dos materiais testados para o período de estudo. A utilização da planta Luziola peruviana contribuiu no máximo com 2,11% da remoção de fósforo total, contudo foi observada importante função do sistema radicular no tempo de percolação, contribuindo para maior tempo de contato do efluente com material suporte, especialmente para o caso da brita. O uso de areia de granulometria grossa possibilitou eficiência de remoção de fósforo superior a 85%, entretanto, a massa de fósforo retida por unidade de área no sistema utilizando brita 0 apresentou valores duas vezes superiores aos obtidos para os leitos preenchidos com areia. / This research evaluated two alternatives to phosphorus removal from domestic wastewater: use of intermittent sand filters with materials addition with potential phosphorus binding and use of constructed wetlands with macrophytes potential phosphorus assimilation. These present themselves as technologies suitable for small communities or single family houses and can be used as a intermediate or final stage of wastewater treatment. The systems based on intermittent feed get satisfactory removal of organic matter and ammonia-N, but they have reduced efficiency of phosphorus and nitrate removal. The aim of present study was to evaluate two techniques for phosphorus removal: use of materials with potential removal of phosphorus, in the intermittent sand filters, and plants with capacity for assimilation of phosphorus metabolism, in the vertical flow constructed wetlands. The materials added to the sand filters with the potential removal of phosphorus were the Machine Bit and Electric Arc Furnace Slag. The fractions of materials added were: 10%, 20% and 40% related to material support weight. The plants tested were Luziola peruviana, which has in its constitution a high concentration of phosphorus and Typha latifolia, widely used in constructed wetlands. The support materials tested were gravel and sand. The use of materials with potential removal of phosphorus aid in the removal of phosphorus, which is more significant in the beds with Machine Bit. Difference of phosphorus removal was not observed for the different fractions of the materials tested for the study period. The use of the plant Luziola peruviana contributed at the most with 2,11% of removal of total phosphorus, however important role of the root system was observed in the percolation time, contributing to larger time of contact of wastewater with support materials, especially for use of coarse material, as it the coarse gravel. The use of coarse sand allowed removal efficiency of phosphorus higher than 85%, however, the mass of phosphorus retained per unit area in the system using gravel present values twice higher than obtained to the beds filled with sand.
114

Evaluation of Pond/Wetland/Vegetative Filter System to Treat Beef Manure Pile and Outdoor Confinement Area Runoff

Mejia Franco, Maria Juliana 10 December 2018 (has links)
Regulations with respect to the storage and handling of animal waste by livestock operations state that no person shall keep animals in a permanent confinement area unless there is a nutrient management strategy. Various studies indicate that constructed wetlands and vegetative filters are effective add-on technologies to supplement the treatment provided by conventional sedimentation pond systems in livestock operations. Seven months of data from a Pond/Wetland/Vegetative Filter system receiving cattle feedlot runoff were used to i) evaluate its efficiency removing organic matter, solids and nutrients from water, (ii) quantify constructed wetland kinetic removal rates described by the P-C-k model and examine the impact of temperature, (iii) evaluate and compare the performance of a two types of vegetative filter systems at different hydraulic loading rates; and (iv) recommend an optimum management option with design loading for beef producers. Results indicate that the effect of isolated rain events on the performance of the wetland showed to be contingent on the intensity of the event, former humidity conditions of the feedlot and the hydraulic capacity of the wetland. This experiment suggests that even relatively small VFSs or short FPs can markedly improve quality of runoff from livestock operations, and that it is possible to achieve significant mass and concentration removals if they are properly operated and maintained in conjunction with a pre-treatment system. The Pond/Wetland/Vegetative Filter system was effective at reducing Chemical Oxygen Demand COD (+92%), Total Phosphorus (+93%), Orthophosphate as P (+91%), Total Inorganic Nitrogen (+96%), Ammonia as N (+97%) and Nitrate as N (+82%) from manure and exercise yard runoff, providing a cost-effective treatment option for beef producers.
115

Análise econômica de dois sistemas naturais de tratamento de água residuária na suinocultura

Jasper, Samir Paulo [UNESP] 05 June 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-06-05Bitstream added on 2014-06-13T19:31:30Z : No. of bitstreams: 1 jasper_sp_me_botfca.pdf: 792511 bytes, checksum: 4bdbd9741d526729aa0258b4ad5f7d95 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O grande desenvolvimento obtido pela suinocultura brasileira deve-se, principalmente, à intensificação dos sistemas produtivos implicando em aumento da densidade, restrição de espaço, da movimentação, além da melhoria genética e nutricional. Animais com elevadas taxas de ganho de peso e eficiência alimentar são, cada vez mais, confinados e alimentados com dietas contendo maior densidade de nutrientes. A adoção de sistemas confinados de produção tem trazido, entretanto, graves problemas operacionais como a concentração de dejetos e o considerável aumento do uso de água para limpeza das instalações. Para solucionar tal problema é importante a utilização de técnicas simples e com baixo custo de instalação, como por exemplo, o sistema inovador de alagados construídos para o tratamento de águas residuárias provenientes da suinocultura. Por outro lado, há técnicas difundidas há bastante tempo, como exemplo, as lagoas de estabilização, pioneiras no Brasil. A composição e o volume das águas residuárias oriundas da suinocultura têm relação direta com o manejo dos dejetos adotado. A adoção de sistemas de manejos de resíduos de forma mais racional evita a perda de água, permitindo uma produção ambiental mais justa com baixo custo. 2 Este trabalho teve por objetivo desenvolver uma análise econômica detalhada entre os sistemas de alagados construídos, tipo combinado e lagoas de estabilização, do modelo facultativa, em função de seis tamanhos de granjas de terminação e dois manejos aplicados nos dejetos (manejo úmido x manejo seco). Os resultados mostraram que o sistema de alagados construído combinado, operando com manejo seco dos dejetos, foram as hipóteses que apresentaram os melhores índices econômicos, ou seja, os menores custos de implantação, anual, por suíno e por quilograma de carne produzida... / The great Brazilian pig breeding development was done due to the intensification of productive systems with density increase, space restriction and movement, and also genetic and nutritional improvement. Animals with high weigh gain rate and feed efficiency are restricted and feed with high density nutrient diet. However, a restricted production system has brought severe operational problems such as dregs concentration and an increase necessity to use water to keep the installations clean. In order to solve this problem, is important to use simple techniques and low cost installations, for example the innovator system called combine wetlands, to treat the pig breeding waste water. On the other side, techniques used for a long time such as facultative pond was pioneer in Brazil. The components and volume of waste dreg water from pig breeding have a direct relation with the adopted dreg management system. The adoption of a rational dreg management system avoids water waste allowing an environmental fair production with low production cost. This work developed a detailed economical analysis between the constructed wetland system, model combine and stabilization pond, type facultative, in function of six pig end raising grange size and two dreg management systems (alternative x conventional). The results showed the constructed wetlands working with dried dejects management system the hypothesis with best economic indexes, such as a lower implementation cost, annual cost, cost per animal and per kilogram of produced meat and also required the smaller recommended area. At pig end raising granges with wet dejects management, lower implementation cost, annual cost, cost per animal and per kilogram of produced meat was found on stabilization ponds type facultative, however this technique requires big areas to be used.
116

Plynné produkty mikrobiálního rozkladu v umělém mokřadu využívaném pro čištění odpadních vod / Gaseous products of microbial decomposition of organic pollution in constructed wetland used for wastewater treatment.

ŠTĚPÁNEK, Jindřich January 2007 (has links)
This master thesis is dealing with monitoring of gaseous products of microbial decomposition of organic pollution in constructed wetland. This wetland was used for wastewater treatment in a village Slavošovice, Czech Republic. Emissions of CO2, CH4 and N2O were measured in one treatment bed of the system. The emissions were quantified, their seasonal course was followed, and the main factors affecting gaseous emissions were identified. Only 3 % of total C emissions were in form of methane, N2O emissions were negligible and only 1,5 % of nitrogen denitrified were in form of N2O. Carbon and nitrogen balances of the system were estimated.
117

Podzemní biomasa rákosu obecného (Phragmites australis) na vegetační kořenové čistírně / Below-ground biomass of the common reed (Phragmites australis) in a constructed wetland used for wastewater treatment

MOULISOVÁ, Lenka January 2010 (has links)
My thesis is a part of the project GACR 206/06/0058 Monitoring of selected heavy metals and risk elements in a wastewater cleaning process in artificial wetlands. The goal is to evaluate temporal and spatial variability of underground biomass of Phragmites australis in the artificial wetland used for wastewater treatment in Slavošovice. The destructive method was used for the sampling. The aboveground biomass was determined from six samples taken at the inflow and six samples at the outflow. The belowground biomass (in 2008) was estimated from two samples taken at the inflow and two samples at the outflow. In 2009, the belowground biomass was determined from six samples taken from the inflow and six samples from the outflow. The analysis of the root structure was determined from 12 samples collected at the inflow and 12 samples of the outflow. The mean total aboveground biomass reached 1039 g.m-2 at the inflow and the 1749 g.m-2 at the outflow. Average total belowground biomass in 2009 reached the inflow 1718 g.m-2 and 1562 g.m-2 at the outflow. The average total length of roots growing from one node to was 284,7 m.m-2 and 324,9 m.m-2 in the inflow and outflow part, respectively. Average specific root length of the inflow was 2589,5 cm.g-1 and the outflow 2956,9 cm.g-1. The average total length of roots reaching the inflow of two kilometers and three kilometers of inflow.
118

Estudo comparativo de leitos percoladores e banhados construídos de fluxo vertical aplicados à remoção de fósforo em esgoto sanitário

Leal, Felipe Kruger January 2009 (has links)
A presente pesquisa avaliou duas alternativas para a remoção de fósforo em esgoto sanitário: uso de filtros percoladores com adição de material com potencial de ligação de fósforo e uso de banhados construídos com macrófitas com potencial assimilação de fósforo. Estas tecnologias são apropriadas para pequenas comunidades ou residências unifamiliares e também podem ser utilizadas como etapa no tratamento dos esgotos. Estes sistemas apresentam remoção satisfatória de matéria orgânica e nitrogênio amoniacal, contudo apresentam diminuta eficiência de remoção de fósforo e nitrato. Na presente pesquisa foram estudadas duas técnicas para aumentar a remoção de fósforo: utilização de materiais com potencial de remoção de fósforo nos filtros percoladores, e plantas com alta capacidade de assimilação de fósforo nos banhados construídos. Os materiais adicionados aos leitos percoladores com potencial de remoção de fósforo foram: Cavaco de Usinagem e Escória de Aciaria Elétrica. As frações de materiais adicionados foram: 10%, 20% e 40% em peso em relação ao material suporte. As plantas utilizadas foram a Luziola peruviana, a qual apresenta em sua constituição alta concentração de fósforo e a Typha latifolia, já amplamente utilizada em banhados construídos. Os materiais utilizados como meios suportes foram brita e areia. A adição de materiais com potencial remoção de fósforo auxiliou na remoção do nutriente, a qual foi mais significativa nos leitos contendo Cavaco de Usinagem. Não foi observada diferença de remoção de fósforo para as diferentes frações dos materiais testados para o período de estudo. A utilização da planta Luziola peruviana contribuiu no máximo com 2,11% da remoção de fósforo total, contudo foi observada importante função do sistema radicular no tempo de percolação, contribuindo para maior tempo de contato do efluente com material suporte, especialmente para o caso da brita. O uso de areia de granulometria grossa possibilitou eficiência de remoção de fósforo superior a 85%, entretanto, a massa de fósforo retida por unidade de área no sistema utilizando brita 0 apresentou valores duas vezes superiores aos obtidos para os leitos preenchidos com areia. / This research evaluated two alternatives to phosphorus removal from domestic wastewater: use of intermittent sand filters with materials addition with potential phosphorus binding and use of constructed wetlands with macrophytes potential phosphorus assimilation. These present themselves as technologies suitable for small communities or single family houses and can be used as a intermediate or final stage of wastewater treatment. The systems based on intermittent feed get satisfactory removal of organic matter and ammonia-N, but they have reduced efficiency of phosphorus and nitrate removal. The aim of present study was to evaluate two techniques for phosphorus removal: use of materials with potential removal of phosphorus, in the intermittent sand filters, and plants with capacity for assimilation of phosphorus metabolism, in the vertical flow constructed wetlands. The materials added to the sand filters with the potential removal of phosphorus were the Machine Bit and Electric Arc Furnace Slag. The fractions of materials added were: 10%, 20% and 40% related to material support weight. The plants tested were Luziola peruviana, which has in its constitution a high concentration of phosphorus and Typha latifolia, widely used in constructed wetlands. The support materials tested were gravel and sand. The use of materials with potential removal of phosphorus aid in the removal of phosphorus, which is more significant in the beds with Machine Bit. Difference of phosphorus removal was not observed for the different fractions of the materials tested for the study period. The use of the plant Luziola peruviana contributed at the most with 2,11% of removal of total phosphorus, however important role of the root system was observed in the percolation time, contributing to larger time of contact of wastewater with support materials, especially for use of coarse material, as it the coarse gravel. The use of coarse sand allowed removal efficiency of phosphorus higher than 85%, however, the mass of phosphorus retained per unit area in the system using gravel present values twice higher than obtained to the beds filled with sand.
119

Estudo comparativo de leitos percoladores e banhados construídos de fluxo vertical aplicados à remoção de fósforo em esgoto sanitário

Leal, Felipe Kruger January 2009 (has links)
A presente pesquisa avaliou duas alternativas para a remoção de fósforo em esgoto sanitário: uso de filtros percoladores com adição de material com potencial de ligação de fósforo e uso de banhados construídos com macrófitas com potencial assimilação de fósforo. Estas tecnologias são apropriadas para pequenas comunidades ou residências unifamiliares e também podem ser utilizadas como etapa no tratamento dos esgotos. Estes sistemas apresentam remoção satisfatória de matéria orgânica e nitrogênio amoniacal, contudo apresentam diminuta eficiência de remoção de fósforo e nitrato. Na presente pesquisa foram estudadas duas técnicas para aumentar a remoção de fósforo: utilização de materiais com potencial de remoção de fósforo nos filtros percoladores, e plantas com alta capacidade de assimilação de fósforo nos banhados construídos. Os materiais adicionados aos leitos percoladores com potencial de remoção de fósforo foram: Cavaco de Usinagem e Escória de Aciaria Elétrica. As frações de materiais adicionados foram: 10%, 20% e 40% em peso em relação ao material suporte. As plantas utilizadas foram a Luziola peruviana, a qual apresenta em sua constituição alta concentração de fósforo e a Typha latifolia, já amplamente utilizada em banhados construídos. Os materiais utilizados como meios suportes foram brita e areia. A adição de materiais com potencial remoção de fósforo auxiliou na remoção do nutriente, a qual foi mais significativa nos leitos contendo Cavaco de Usinagem. Não foi observada diferença de remoção de fósforo para as diferentes frações dos materiais testados para o período de estudo. A utilização da planta Luziola peruviana contribuiu no máximo com 2,11% da remoção de fósforo total, contudo foi observada importante função do sistema radicular no tempo de percolação, contribuindo para maior tempo de contato do efluente com material suporte, especialmente para o caso da brita. O uso de areia de granulometria grossa possibilitou eficiência de remoção de fósforo superior a 85%, entretanto, a massa de fósforo retida por unidade de área no sistema utilizando brita 0 apresentou valores duas vezes superiores aos obtidos para os leitos preenchidos com areia. / This research evaluated two alternatives to phosphorus removal from domestic wastewater: use of intermittent sand filters with materials addition with potential phosphorus binding and use of constructed wetlands with macrophytes potential phosphorus assimilation. These present themselves as technologies suitable for small communities or single family houses and can be used as a intermediate or final stage of wastewater treatment. The systems based on intermittent feed get satisfactory removal of organic matter and ammonia-N, but they have reduced efficiency of phosphorus and nitrate removal. The aim of present study was to evaluate two techniques for phosphorus removal: use of materials with potential removal of phosphorus, in the intermittent sand filters, and plants with capacity for assimilation of phosphorus metabolism, in the vertical flow constructed wetlands. The materials added to the sand filters with the potential removal of phosphorus were the Machine Bit and Electric Arc Furnace Slag. The fractions of materials added were: 10%, 20% and 40% related to material support weight. The plants tested were Luziola peruviana, which has in its constitution a high concentration of phosphorus and Typha latifolia, widely used in constructed wetlands. The support materials tested were gravel and sand. The use of materials with potential removal of phosphorus aid in the removal of phosphorus, which is more significant in the beds with Machine Bit. Difference of phosphorus removal was not observed for the different fractions of the materials tested for the study period. The use of the plant Luziola peruviana contributed at the most with 2,11% of removal of total phosphorus, however important role of the root system was observed in the percolation time, contributing to larger time of contact of wastewater with support materials, especially for use of coarse material, as it the coarse gravel. The use of coarse sand allowed removal efficiency of phosphorus higher than 85%, however, the mass of phosphorus retained per unit area in the system using gravel present values twice higher than obtained to the beds filled with sand.
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Estudo da remoção de metais por leitos cultivados utilizando a fluorescência de raios X por reflexão total com radiação síncrotron / Study of the metal removal for constructed wetland using the fluorescence of rays X for total reflection with radiation syscrotron

Avelino Neto, Sebastião 16 August 2018 (has links)
Orientador: Silvana Moreira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-16T10:36:10Z (GMT). No. of bitstreams: 1 AvelinoNeto_Sebastiao_D.pdf: 6321049 bytes, checksum: a54827db20bdd0eedb9943b48ef60d17 (MD5) Previous issue date: 2008 / Resumo: O presente trabalho teve como objetivo avaliar a operação e o desempenho de seis Leitos Cultivados de Fluxo Subsuperficial que operaram como pós-tratamento de um Tanque Séptico Modificado, instalados na Faculdade de Engenharia Agrícola da Universidade Estadual de Campinas. O sistema em estudo é composto por três leitos retangulares e três quadrados, dispostos em paralelo. Como meio suporte utilizou-se brita e foram cultivadas duas espécies de macrófitas emergentes (Typha sp. e Eleocharis sp.). Foi estudado o desempenho do leito cultivado para diferentes tempos de detenção hidráulicos e para isto foram coletadas amostras das folhas das macrófitas, do perfil do meio suporte em diferentes profundidades, da água residuária no afluente e no efluente de cada leito cultivado. Para a análise quantitativa foi empregada a técnica de Fluorescência de Raios X por Reflexão Total com Radiação Síncrotron. Para a avaliação do desempenho dos leitos estudados as concentrações de Cr, Mn, Fe, Cu, Zn e Pb foram avaliadas nas folhas das macrófitas, no meio suporte, no afluente e no efluente. Foi verificado que o desempenho do leito quadrado cultivado com Eleocharis foi superior ao retangular para os seguintes elementos: Mn, Fe, Cu e Zn. Para os elementos Cr e Pb o leito retangular cultivado com Eleocharis teve um melhor desempenho. Verificou-se que tanto no leito quadrado quanto no retangular as folhas de Eleocharis e Typha apresentaram eficiência de remoção superior a do meio suporte. Assim como no leito cultivado com Eleocharis, foi observado um melhor desempenho do leito cultivado com Typha quadrado para Mn, Fe, Cu e Zn, enquanto que para Cr e Pb o leito cultivado com Typha retangular apresentou melhor desempenho. No sistema de leito cultivado de geometria quadrada com Typha e Eleocharis e Controle removeram os metais Fe, Cu e Zn a limites permitidos pela legislação em qualquer dos tempos de detenção hidráulico empregado. No entanto para a remoção de Cr a níveis estabelecidos pela legislação é recomendado a operação do sistema com tempo de detenção hidráulico de 4 dias, e para Pb os tempos de detenção hidráulico recomendados são os de 4 e 6 dias. Para o leito retangular cultivado com Eleocharis e Typha, assim como no leito controle podemos observar que para os elementos Fe, Cu e Zn, as concentrações estão abaixo dos valores máximos permitidos pela legislação de lançamento de efluentes, para todos os tempos de detenção hidráulico. Entretanto para uma remoção eficiente de Cr, Mn e Pb os tempos de detenção de 4 e 6 dias são os mais recomendados para a operação do sistema. Os leitos controles quadrado e retangular tiveram eficiência de remoção inferior ao dos leitos cultivados com as macrófitas. O meio suporte nas profundidades de 10, 30 e 50 cm do leito cultivado de geometria quadrado e retangular cultivados com as macrófitas Typha sp. e Eleocharis sp., removeu os metais Cr, Mn, Fe, Cu, Zn e Pb de forma semelhante, ou seja, não houve uma profundidade que tivesse eficiência de remoção superior as demais / Abstract: The purpose of this work was evaluated the operation and performance of six constructed wetland of subsuperface flow, operating as post-treatment of a septic tank, installed on Agricultural Engineering College at University of Campinas. The system in study containing three square units, disposed in parallel. The substrate used was gravel and two emergent macrophytes species were cultivated (Typha sp. and Eleocharis sp.). The performance of the units were studied for different hydraulic residence times (2, 3, 4 and 6 days) and for this leaf of the macrophytes, substrate in different depths, wastewater in all units were collected. For quantitative analysis Synchrotron Radiation Total Reflection X-ray Fluorescence technique was employed. For evaluation of the performance in the constructed wetlands concentrations of Cr, Mn, Fe, Cu, Zn e Pb in leaf macrophytes, substrate, entrance and exit of the system were determined. The performance of the square unit with Eleocharis was higher than rectangular shape for Mn, Fe, Cu and Zn elements. For Cr and Pb the rectangular unit with Eleocharis presented better performance. Leaf of Eleocharis and Typha showed removal efficiency higher than substrate for square and rectangular units. As in the unit with Eleocharis a better perfomance was observed in a square unit cultivated with Typha for Mn, Fe, Cu and Zn, while for Cr and Pb the rectangular shape with Typha presented better performance. In the square system cultivated with Typha, Eleocharis and the control removed Fe, Cu and Zn to levels permitted by the legislation for all hydraulic residence times. Moreover for Cr removal to levels established by the legislation the operation with 4 days of hydraulic residence time was indicated and for Pb the recommended times were 4 and 6 days. For rectangular systems cultivated with Eleocharis and Typha, as the control unit, Fe, Cu and Zn, concentrations were smaller than the permissive values established by the legislation for all hydraulic residence times. By the order hand for a efficient removal of Cr, Mn and Pb the residence times of 4 and 6 days were most recommended for the system operation. Square and rectangular control units showed efficiency removal smaller than units containing the macrophytes. The removal of Cr, Mn, Fe, Cu, Zn and Pb metals by the substrate in 10, 30 and 50 cm depths of square and rectangular shapes cultivated with the two macrophytes showed no significative difference / Doutorado / Recursos Hidricos / Doutor em Engenharia Civil

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