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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.
591

Processo de tratamento biológico e físico-químico combinados visando o reúso de esgoto sanitário / Biological treatment process and physical-chemical combinations aiming reuse sewage

Gabriela Laila de Oliveira 01 June 2012 (has links)
Este trabalho teve por objetivo avaliar a combinação de processos de tratamento de esgoto e a partir dos efluentes produzidos com diferentes padrões de qualidade elencar as possibilidades para reúso de acordo com legislação internacional. Foi feito o monitoramento da estação piloto de tratamento de esgoto constituído reator UASB seguido de lodo ativado cujos efluentes foram utilizados neste estudo, não somente para análises físico-químicas e microbiológicas, mas também para posterior tratamento físico-químico em laboratório com equipamento jarteste utilizando dois coagulantes - cloreto férrico e sulfato de alumínio. Após os tratamentos combinados seis amostras diferentes foram analisadas, sendo elas: efluente do UASB, efluente do lodo ativado, tratamentos UASB-\'AL IND.2\'(\'SO IND.4\')IND.3\', UASB-\'FE\'CL IND.3\', lodo ativado-\'AL IND.2\'(\'SO IND.4\')IND.3\' e lodo ativado-\'FE\'CL IND.3\'. Os ensaios realizados com cloreto férrico foram os que melhor promoveram remoção dos microrganismos indicadores e de (oo)cistos, de DQO e SST. Porém, mesmo após o tratamento físico-químico não será possível reutilização agrícola, urbana e/ou industrial dos efluentes, conforme legislação internacional e diretrizes da OMS, uma vez que a concentração de microrganismos indicadores ainda é muito elevada. Os valores médios de E. coli, coliformes totais e Giardia spp., mesmo após o tratamento que forneceu melhor remoção microbiológica (lodo ativado \'FE\'CL IND.3\') foram de 4,31 x \'10 POT.2\', 7,68 x \'10 POT.3\' e 2,17 x \'10 POT.2\', respectivamente. / The present dissertation reports to evaluate the combination of process wastewater treatment and from the effluent produced with different standards quality list the possibilities for reuse in accordance with international Law. Was monitored from the wastewater treatment plant pilot consists of a UASB reactor followed by activated sludge whose effluents were used in this study not only physical-chemical and microbiological analyzes, but also for subsequent physical-chemical treatment in the laboratory with equipment jartest using two coagulants ferric chloride and aluminum sulfate. After the treatments combined six different samples were analyzed: UASB effluent, activated sludge effluent, treatments UASB-\'AL IND.2\'(\'SO IND.4\')IND.3\', UASB-\'FE\'CL IND.3\', activated sludge-activated sludge and activated sludge-\'FE\'CL IND.3\'. The tests with ferric chloride were better promoted removal of the microbiological indicators and (oo)cysts, COD and TSS. However, even after physical-chemical treatment will not be possible wastewater reuse in agriculture, urban and/or industrial, according international law and the WHO guidelines, since the concentration of indicator microorganisms is still very high. The average values of E. coli and total coliform and Giardia spp., even after the treatment which promoted better microbiological removal, were 4,31 x \'10 POT.2\', 7,68 x \'10 POT.3\' e 2,17 x \'10 POT.2\', respectively.
592

Uso da irrigação subsuperficial com efluente de esgoto doméstico em área cultivada com cana-de-açúcar / Use of subsurface irrigation with domestic sewage effluent in area cultivated with sugar cane

Sousa, Allan Charlles Mendes de 20 August 2018 (has links)
Orientador: Edson Eiji Matsura / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-20T09:51:07Z (GMT). No. of bitstreams: 1 Sousa_AllanCharllesMendesde_M.pdf: 11587705 bytes, checksum: 9f6fbadbba811b3eac53643a17b80816 (MD5) Previous issue date: 2012 / Resumo: O uso de efluente de esgoto doméstico (EED) apresenta-se como uma alternativa na irrigação de culturas economicamente exploradas servindo como fonte extra de água e de nutrientes essenciais ao desenvolvimento das plantas. O presente trabalho teve como objetivo avaliar as alterações físicas e químicas do solo, o desenvolvimento radicular e a produtividade da cana de- açúcar irrigada com EED, tratado por lagoa de estabilização e aplicado por gotejamento subsuperficial. O experimento foi realizado na cidade de Piracicaba-SP (22° 46' 24" S, 47° 36' 32" W) numa área cultivada com cana-de-açúcar, situada ao lado da estação de tratamento de esgoto do bairro CECAP. O delineamento experimental adotado foi o de blocos dispostos no esquema de faixas, com três repetições e seis tratamentos; TSQ (cana-de-açúcar cultivada em sequeiro), T50% (cana-de-açúcar irrigada com EED atendendo 50% da avapotranspiração - ETP), T100% (cana-de-açúcar irrigada com EED atendendo 100% da ETP), T200% (cana-de açúcar irrigada com EED atendendo 200% da ETP), T100Herb (cana-de-açúcar irrigada com EED acrescido de herbicida atendendo 100% da ETP) e T100Cl (cana-de-açúcar irrigada com EED acrescido de hipoclorito de sódio atendendo 100% da ETP). A irrigação com EED proporcionou um menor desenvolvimento de raízes, tanto lateral como em profundidade, quando comparado ao TSQ. A irrigação promoveu um incremento de nutrientes no solo, principalmente no tratamento que aplicou a maior lâmina (T200%). Nesse tratamento, observou-se um maior aporte de Ca2+, Mg2+, Na+ e N, reduções significativas nos teores de Al3+ e H+ e alto potencial para o fornecimento de P ao solo. Além disso, não foram observados problemas relacionados à qualidade física do solo devido ao fornecimento de Na+ pelo EED. O uso de EED proporcionou incrementos significativos na produtividade da cultura / Abstract: The use of domestic sewage effluent (DSE) is presented as an alternative for irrigation of economically exploited crops, functioning as an extra source of water, and essential nutrients for plant development. The present work aimed to evaluate the physical and chemical changes of soil, root development, and productivity of sugar cane irrigated with DSE, that was treated using stabilization, and was applied by a subsurface drip irrigation system. The experiment was done in Piracicaba-SP (22 ° 46 '24 "S, 47 ° 36' 32" W) on an area of sugar cane situated next to the sewage treatment station in the district of CECAP. The experimental model was arranged in block of tracks with three repetitions and six treatments; TSQ (cane sugar grown on rainfed), T50% (sugar cane irrigated with DSE serving 50% the evaporation and transpiration - ETP), T100% (sugar cane irrigated with DSE serving 100% of the ETP), T200% (sugar cane irrigated with DSE serving 200% of the ETP), T100Herb (sugar cane irrigated with DSE and in addition herbicide serving 100% of ETP) and T100Cl (sugar cane irrigated with DSE plus sodium hypochlorite serving 100% of the ETP). Irrigation with DSE afforded a lower root development, both laterally and in depth, as compared to TSQ. Irrigation promoted an increase of nutrients in the soil, especially in the treatment that applied to the highest water depth (T200%). In this treatment, it was observed a larger contribution of Ca2+, Mg2+, Na+ and N, significant reductions in the levels of Al3+ and H+, and high efficiency on the supply of P to the soil. In addition, no problems were observed related to the physical quality of the ground due to the provision of Na+ by DSE. The use of DSE provided significant increases in crop productivity / Mestrado / Agua e Solo / Mestre em Engenharia Agrícola
593

Pepper Mild Mottle Virus as a Surrogate for Enteric Viruses: Implications for Assessing Water Quality

Symonds, Erin Michelle 03 November 2016 (has links)
Less than 10% of the world’s domestic wastewater is disinfected prior to discharge into surface waters; therefore, human exposure to diverse wastewater-related pathogens results in millions of cases of illness each year. Among the enteric pathogens, viruses represent an important group of emerging pathogens and are frequently the cause of food- and water-borne outbreaks of illness. Although the World Health Organization and many government agencies mandate the use of bacterial indicators to identify poor microbial water quality, it is well known that these indicators poorly correlate with fecal pollution contamination events and risk of disease. The field of public health-related environmental microbiology has made significant advances over the last twenty years; however, there is still a need for improved methods to identify poor microbial water quality and manage health risks associated with water-related activities (e.g., recreation, shellfish harvesting, irrigation). Furthermore, it is imperative to effectively detect fecal pollution in the environment as well as determine the extent of pathogen removal during (waste)water treatment to meet the Sustainable Development Goals associated with water and food security as well as the water reuse recommendations by the U.S. National Research Council. This dissertation directly addressed the need to identify an improved viral indicator by exploring the application of pepper mild mottle virus (PMMoV), a virus of dietary origin that is extremely abundant in human feces, as a surrogate for enteric viruses in diverse settings and contexts. Using a reverse transcription quantitative polymerase chain reaction (RT-qPCR) method, PMMoV was compared with other indicators, index surrogates, and reference pathogens for assessing surface water quality in a developed country (Appendix A) and developing country context (Appendix B and C). In addition, the applicability of PMMoV as a (waste)water treatment process indicator was demonstrated in natural treatment systems in developing countries (Appendix C and D) and artificial treatment systems (Appendix E). In all settings, PMMoV always co-occurred with at least one reference pathogen, index organism, and/or indicator; additionally, PMMoV was detected more frequently and in higher concentrations than other reference pathogens and indicators. Three investigations also associated PMMoV detection with predicted human health risks greater than the health benchmark for recreation and water reuse activities (Appendix A, C, and D). Additionally, PMMoV facilitated an improved understanding of virus-particle interactions in wastewater treatment pond systems (Appendix D) and allowed for an improved understanding of virus removal with respect to riverbank filtration systems and wastewater reuse in agriculture (Appendix C). PMMoV was established as a valuable component of the microbial source tracking toolbox in Costa Rica (Appendix B) and appeared to be useful in Bolivia (Appendix C). Finally, a paradigm shift in (waste)water management is occurring, in which routine monitoring is being replaced by a more holistic approach that includes sanitary surveys, targeted water quality monitoring, and exploratory quantitative microbial risk assessment. To support and complement this paradigm shift, field-based, laboratory-free methods are needed to identify and/or infer the presence of enteric viruses (Appendix F). Collectively, all the investigations presented here confirm the use of PMMoV as a surrogate for enteric viruses; however, its utility depends on the context and research question.
594

Studie variant odkanalizování obce Kamenný Malíkov / The study alternatives village sewer system Kamenný Malíkov

Rőssová, Markéta January 2019 (has links)
The diploma thesis is focused on the possibilities of drainage of waste water and its subsequent liquidation in the village of Kamenný Malíkov. The aim of this diploma thesis is the elaboration of variant solutions for drainage of Kamenný Malíkov. Furthermore, the proposal for wastewater treatment, the economic comparison of variants and the recommendation of the unsuitable variant. The diploma thesis deals with the proposal of predominantly gravitational way of drainage of waste water in combination with the pressure, due to incline terrain in the village. Each eventuality has wastewater treatment method designed.
595

Studie pro návrh malé kořenové čistírny na konkrétní lokalitu / Study of small vegetable waste water treatment plant design for specific locality

Netopilík, Jan January 2020 (has links)
Constructed wetland is one of ways of domestic wastewater treatment that allows reuse of treated water. The thesis acquainted with run principles, with a design for a family house, that includes different solutions of technologic parts with advice for a reliable run and theoretical financial costs.
596

Sledování obsahu sulfonamidů v odpadních vodách z čistíren odpadních vod s různými technologiemi čištění / Monitoring of sulfonamides in wastewater from sewage treatment plants with different treatment technologies

Chaloupková, Petra January 2015 (has links)
The aim of this thesis is to determine the presence of pharmaceuticals in wastewater from several wastewater treatment plants (WWTPs) with different number of equivalent persons and different treatment technologies. Five sulfonamides were chosen for a determination due to their wide usage in human and veterinary medicine practice. The specific compounds are sulfamerazine, sulfamethazine, sulfapyridine, sulfathiazole a sulfamethoxazole. For the determination of those sulfonamides, an UHPLC/DAD analytical method was chosen and optimized. There was also a need for optimization of SPE extraction method, especially a sample volume optimization. 250 mL was chosen as an ideal volume of wastewater sample for SPE. The optimized method was used for determination of sulfonamides in real wastewater samples from WWTP in Podivín, Pohořelice, Hustopeče, Valtice, Lednice and Mikulov. Average concentrations of pharmaceuticals in influent and effluent wastewater samples were in a range of 0,1 – 1 µg/l. The concentration of sulfonamides was mostly found higher in influent samples and lower in effluent samples. It can be said that a partial recovery of sulfonamides on WWTPs was observed.
597

Posouzení účinnosti čištění odpadních vod pomocí testů ekotoxicity / Assessment of the efficiency of wastewater treatment plant using ecotoxicity tests

Urminská, Barbora January 2015 (has links)
The possibilities of environmental pollution control are increasing and more advanced wastewater treatment methods are being emphasized, as well as more specific control of contaminants presence in treated waters. That is why it becomes relevant to perform not only chemical analysis but also ecotoxicological bioassays as the means of evaluation of biological effects caused by wastewater discharges to ecosystems. No wastewater treatment plant is able to treat the water perfectly – it can only decrease the pollution level to an acceptable value. Therefore it is important to find out if the treatment process is sufficient to provide a satisfactory decrease of ecotoxicity and also what effects to the organisms in recipient will be caused by wastewater discharges. The thesis is focused on the evaluation of wastewater ecotoxicity. In the experimental part of the thesis, wastewater samples were collected at four wastewater treatment plants in the Czech Republic. At one of them also the sludge samples were taken. The aim was to evaluate the efficiency of wastewater treatment by selected ecotoxicological bioassays. The results have shown that the efficiency of wastewater treatment plants with secondary treatment is sufficient to reduce acute toxic effects to the minimum. Average toxicity removal was over 80 % at three of four evaluated wastewater treatment plants. At the fourth WWTP it was 41 %, however, at this WWTP high efficiency of treatment is not necessary.
598

Energetické využití čistírenských kalů / Energetic utilisation of sewage sludge

Tlašek, Miroslav January 2016 (has links)
Diploma thesis deals with issues related to final treatment sludge. Sewage sludge is an inevitable product of wastewater treatment. Also, most of them concentrated pollution. Most of pollution are concentrated in to them. And because it contains a large percentage of combustibles. Before thermal utilization, it is necessary to appropriately adjust the sludge. Thermal sludge utilization offers the most effective method of energy recovery. It is an energy conversion in the sludge, to heat and electricity. In the vast majority, if not the co-firing, it is necessary to modify the sludge and so it is dried. This is the optimal use of modern technology. There are several variations possible use. Unfortunately it is not in general able to propose the most appropriate technology or methodology, how to make best use of sewage sludge. Specific assignment usually have their own characteristics. In my work I will therefore first try to outline possible technology and in the second part to suggest sludge terminal for WWTP Hodonín.
599

En god natts sömn och återvunnen energi : Modellering av avloppsvärmeväxling på ett stockholmshotell och spa / Relax and sleep (energy) efficiently : Modelling wastewater heat recovery in a Stockholm hotel and spa

Korpar Malmström, Sofia January 2015 (has links)
As buildings have become more energy efficient, the energy demand for preparation of domestic hot water stands out as an increasing part of the operational cost and carbon footprint of a building. Most of the heat in the water is used for a short time and then discharged to the main sewer line. Clarion Hotel Stockholm is an example of such a building, with many showers, bathtubs and a spa. The hotel business is growing around the world and its customers demand comfortable stays. A parallel trend is a more environmentally aware tourism and business travel. Hotels show a great potential for energy savings, while still offering comfortable accommodation. In this master's thesis a case study evaluates the possibilities for heat recovery from the wastewater of Clarion Hotel Stockholm. Three types of heat exchangers were modelled in the system dynamic modelling environment STELLA: a horizontal, a vertical and a shower heat exchanger. Recovered heat was used for pre-heating of the incoming water for domestic hot water preparation. The flows of heat through the hotel's tap water and wastewater systems were schematically modelled using system dynamic modelling, which provides a foundation for the development of mathematical models and further research into the area. The first results point to possible reductions of the heating demand for domestic hot water preparation at Clarion Hotel Stockholm.
600

Characterization of microplastics in wastewater

Sabienski, Lina January 2020 (has links)
This study aims to detect how many microplastics and what kind are released from the wastewater treatment plant (WWTP) Skebäck, in Örebro. The study was limited to the analysis of three filters with 50 μm mesh size and one filter with 300 μm mesh size. The samples were taken at different times, two in the fall of 2019 and one in the spring of 2020. Visual characterization was used for the quantification of microplastics, and a lower and upper bound was used. The lower bound represents particles that were deemed identifiable as plastic with high certainty, while the upper bound also includes particles that may have been microplastic. An additional ATR-FTIR analysis was performed on selected microplastics >300 μm.  The presence of microplastics in the effluent from Skebäcks WWTP could be confirmed. The quantity of microplastics per m​3​ (MP/m​3​) trapped on the 50 μm filters were quantified in a range between 0 MP/m​3​ to 291 MP/m​3​ for the lower bound, and 72 MP/m​3​ to 435 MP/m​3​ for the upper bound. The 300 μm filter had considerably less microplastics than the 50 μm filter with 1.8 MP/m​3​. The quantification of fibers on the 50 μm filter and 300 μm filters was not possible due to high blank contaminations. According to the concentration of 63 MP/m​3​ of the lower bound count on the 50 μm filters and the amount of water flowing through Skebäck in 2019, 17 818 935 m​3​, 1.1 billion microplastic particles were released into Svartån that year. In comparison the highest value of the upper bound count, 435 MP/m​3​, gave a release of 7.7 billion microplastic particles. Using the concentration of the 300 μm filter 1.8 MP/m​3​, 32 million microplastics/year were released from Skebäck in 2019. The amount of spheres 50-300 μm released in the effluent from Skebäck was estimated to be 3.7 kg in 2019.

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