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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.
21

Avaliacao de teoxidade aguda e cronica em aguas do Rio Jundiai e em afluentes e efluentes da ETE Novo Horizonte, Jundiai, Sao Paulo / Acute and chronic toxicity evaluation at Jundiaí river, influent and effluent from Novo Horizonte Wastewater Treatment Plant (NHWWP), Jundiaí, São Paulo

NOGUEIRA NETO, ANTONIO C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:54Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:52Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
22

Avaliacao de teoxidade aguda e cronica em aguas do Rio Jundiai e em afluentes e efluentes da ETE Novo Horizonte, Jundiai, Sao Paulo / Acute and chronic toxicity evaluation at Jundiaí river, influent and effluent from Novo Horizonte Wastewater Treatment Plant (NHWWP), Jundiaí, São Paulo

NOGUEIRA NETO, ANTONIO C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:54Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:52Z (GMT). No. of bitstreams: 0 / A cidade de Jundiaí está localizada a aproximadamente 60 Km de São Paulo e tem uma população de 342.983 mil habitantes sendo que 94,37% residem na zona urbana. A cidade está inserida na bacia hidrográfica do Rio Jundiaí, rio que é formado a partir da confluência do Rio Jundiaizinho com o Ribeirão das Taipas e possui uma extensão de 123 quilômetros e sua foz está situada em Salto, na confluência do Rio Jundiaí com o Rio Tietê. Está é menor bacia hidrográfica do estado de São Paulo e também uma das mais industrializadas. A cidade de Jundiaí conta com a Estação de Tratamento de Esgotos Novo Horizonte (ETE Jundiaí), que coleta 98% dos esgotos da cidade, trata 100% de todo esgoto coletado, com eficiência de remoção de 92% de carga orgânica, esgoto que depois do tratamento é lançado no Rio Jundiaí. O objetivo deste trabalho foi utilizar ensaios de toxicidade com organismos aquáticos para avaliar a carga tóxica que chega à ETE, bem como a eficiência do tratamento biológico e a influência da estação no seu entorno. Foram coletadas amostras em 6 pontos distintos; à montante da ETE (P1), na entrada da ETE (P2), na calha de distribuição das lagoas de aeração (P3), nas 2 saídas da ETE (P4 e P5) e à jusante da ETE (P6). As amostras de afluente da ETE foram mais tóxicas que os efluentes da ETE; já os resultados das amostras do rio não apresentaram diferença. Para Vibrio fischeri os valores de CE(i)50 variaram entre 2,23% e 9,39% para a calha de entrada das lagoas de aeração, enquanto que para Daphnia similis variaram entre 15,52% e 89,95%; para a entrada da ETE os valores variaram entre 4,63% e 8,31% para Vibrio fischeri , e 17,68% e não tóxico para Daphnia similis. Nas campanhas onde foram amostradas as saídas da ETE e águas do rio, os ensaios realizados com Vibrio fischeri apresentaram resultados entre 53,55% e não tóxico para águas do rio e 29,46% e não tóxico para o efluente da ETE, já para Daphnia similis, os resultados estão entre 55,92% e não tóxico para águas do rio e 70,97% e não tóxico para o efluente da ETE. Nos ensaios realizados com Ceriodaphnia dubia, a média de nascimentos para águas do rio esteve entre 4,60 e 15,00 enquanto que para o efluente da ETE esteve entre 4,50 e 10,35 para amostra bruta. Os resultados de toxicidade comprovam a eficiência da ETE na remoção de toxicidade porém outros parâmetros devem ser observados para se comprovar o impacto de seus efluentes sobre as águas do rio. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
23

Correlation of Fluorescence Spectroscopy and Biochemical Oxygen Demand (BOD5) Using Regression Analysis

Narteh, Alexander Tetteh 01 July 2015 (has links) (PDF)
This research uses Regression analysis of fluorescence spectroscopy results to correlate with Biochemical Oxygen Demand (BOD5). Fluorescence spectroscopy was applied to samples taken from seven sample sites in the Provo and Orem waste water treatment plants found in Utah County. A total of 161 samples were collected for this research. 23 samples each were taken from four sites in the Provo waste water treatment plant namely Provo head works, aeration basin, primary filter settlement basin and the Provo effluent basin. The Orem head works, the clarifier and the Orem effluent basin were the three sample sites in the Orem waste water treatment plant where 23 samples each were collected to carry out the analysis. The fluorescent characteristics of the samples were determined using fluorescence spectrometry. These intensities were correlated with standard five day Biochemical Oxygen Demand (BOD5) values which were used as a measure of the amount of biodegradable organic material present. Chemical oxygen demand (COD) data were also taken from these treatment plants for correlation purposes. Three different correlation analyses were made which were the correlation of fluorescence spectroscopy excitation-emission matrix (EEM) against (1) individual sites BOD and COD values (2) Provo only and Orem only BOD and COD values (3) combined Provo and Orem BOD and COD values. The correlation of Individual site EEMs against BOD and COD values produced the best results. There was a higher correlation of EEM with BOD data than COD data. The R-squared for the combined Provo and Orem BOD data was 0.756 and that for COD was 0.729. Very high R-squared was obtained for Provo Influent data and Orem Influent data which were 0.955 and 0.946 respectively. This method can be used by wastewater stakeholders in deriving quick results in determining potential pollution events within a shorter time frame. This research demonstrates that there is a correlation between EEM and BOD/COD.
24

Electrochemical and Electroflotation Processes for Milk Waste Water Treatment

Mohammed, Alahmad Suleiman 20 December 2017 (has links)
No description available.
25

Efficiency of soil aquifer treatment in the removal of wastewater contaminants and endocrine disruptors : a study on the removal of triclocarban and estrogens and the effect of chemical oxygen demand and hydraulic loading rates on the reduction of organics and nutrients in the unsaturated and saturated zones of the aquifer

Essandoh, Helen Michelle Korkor January 2011 (has links)
This study was carried out to evaluate the performance of Soil Aquifer Treatment (SAT) under different loading regimes, using wastewater of much higher strength than usually encountered in SAT systems, and also to investigate the removal of the endocrine disruptors triclocarban (TCC), estrone (E1), 17β-estradiol (E2) and 17α-ethinylestradiol (EE2). SAT was simulated in the laboratory using a series of soil columns under saturated and unsaturated conditions. Investigation of the removal of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Dissolved Organic Carbon (DOC), nitrogen and phosphate in a 2 meter long saturated soil column under a combination of constant hydraulic loading rates (HLRs) and variable COD concentrations as well as variable HLR under constant COD showed that at fixed HLR, a decrease in the influent concentrations of DOC, BOD, total nitrogen and phosphate improved their removal efficiencies. It was found that COD mass loading applied as low COD wastewater infiltrated over short residence times would provide better effluent quality than the same mass applied as a COD with higher concentration at long residence times. On the other hand relatively high concentrations coupled with long residence time gave better removal efficiency for organic nitrogen. Phosphate removal though poor under all experimental conditions, was better at low HLRs. In 1 meter saturated and unsaturated soil columns, E2 was the most easily removed estrogen, while EE2 was the least removed. Reducing the thickness of the unsaturated zone had a negative impact on removal efficiencies of the estrogens whereas increased DOC improved the removal in the saturated columns. Better removal efficiencies were also obtained at lower HLRs and in the presence of silt and clay. Sorption and biodegradation were found to be responsible for TCC removal in a 300 mm long saturated soil column, the latter mechanism however being unsustainable. TCC removal efficiency was dependent on the applied concentration and decreased over time and increased with column depth. Within the duration of the experimental run, TCC negatively impacted on treatment performance, possibly due to its antibacterial property, as evidenced by a reduction in COD removals in the column. COD in the 2 meter column under saturated conditions was modelled successfully with the advection dispersion equation with coupled Monod kinetics. Empirical models were also developed for the removal of TCC and EE2 under saturated and unsaturated conditions respectively. The empirical models predicted the TCC and EE2 removal profiles well. There is however the need for validation of the models developed
26

Optimizing Sample Dissolution Methods of Low Water Soluble Intermediate Organic Compounds to Support Environmental Risk Assessment during Active Pharmaceutical Ingredient Manufacturing.

Mohammed, Warda January 2021 (has links)
This project focus on investigating the dissolution of low water-soluble intermediate organic compounds called active pharmaceutical ingredients (API) and organic substances that are manufactured by a pharmaceutical company, Cambrex Karlskoga in Sweden. Several dissolution methods were used and evaluated using methods including total organic carbon (TOC), chemical oxygen demand (COD), biochemical oxygen demand (BOD) and Microtox toxicity test. The selection of solvents were based on previous studies and specifications from the Swedish Institute of Standards, SIS.The performance of eight solvents for different organic substances were evaluated using the above mentioned methods. Solvents that are highly volatile and have low solubility in water were excluded. Therefore, dimethyl sulfoxide (DMSO), dimethylformamide (DMF) and Pluronic F-68, that had highest water solubility, low acute toxicity and not degradable by microorganisms, were further used to dissolve four organic substances. Furthermore, DMSO and DMF were then also used to dissolve four censored chemicals with addition of physical treatment and solvent mixtures (DMF:DMSO with ratio 1:2).Results from each method were discussed and statistical tests were also performed in order to compare different dissolution methods. In addition, quality control and quality assurance were made in order to ensure the quality of measured values from analytical methods. Four organic substances were dissolve in DMSO, DMF and Pluronic F-68 with dissolution ≥79% using six ratios of DMSO and DMF and five ratios of Pluronic F-68 which were analyzed using TOC. Physical treatment increased dissolution of two APIs with 40%. Using BOD, para-aminobenzonic acid (PABA) and 5-nitroisophthalic acid (5-NIPA) had values higher than the guideline values, which indicate high biodegradability of these organic substances. PABA, 5-NIPA and bupivacaine base were acute toxic where PABA showed EC50 values of 27.9 mg/L using DMSO and 36.0 mg/L using DMF, and EC50 values of 5-NIPA were 102 mg/L using DMSO and 84.0 mg/L using DMF, and bupivacaine base had EC50 value of 174 mg/L using solvent mixture (DMF:DMSO with ratio 1:2). With increasing amount of Pluronic F-68, 5-NIPA had increased values of EC50, thereby Pluronic F-68 was not appropriate to use.In conclusion, DMSO and DMF were most appropriate solvents to use in order to dissolve APIs and organic substances with analyte: DMSO ratio of 1:0.5 and analyte: DMF ratio of 1:0.25. In addition, physical treatment could be used in order to increase dissolution of the APIs.
27

Efficiency of soil aquifer treatment in the removal of wastewater contaminants and endocrine disruptors. A study on the removal of triclocarban and estrogens and the effect of chemical oxygen demand and hydraulic loading rates on the reduction of organics and nutrients in the unsaturated and saturated zones of the aquifer.

Essandoh, Helen M.K. January 2011 (has links)
This study was carried out to evaluate the performance of Soil Aquifer Treatment (SAT) under different loading regimes, using wastewater of much higher strength than usually encountered in SAT systems, and also to investigate the removal of the endocrine disruptors triclocarban (TCC), estrone (E1), 17¿-estradiol (E2) and 17¿- ethinylestradiol (EE2). SAT was simulated in the laboratory using a series of soil columns under saturated and unsaturated conditions. Investigation of the removal of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Dissolved Organic Carbon (DOC), nitrogen and phosphate in a 2 meter long saturated soil column under a combination of constant hydraulic loading rates (HLRs) and variable COD concentrations as well as variable HLR under constant COD showed that at fixed HLR, a decrease in the influent concentrations of DOC, BOD, total nitrogen and phosphate improved their removal efficiencies. It was found that COD mass loading applied as low COD wastewater infiltrated over short residence times would provide better effluent quality than the same mass applied as a COD with higher concentration at long residence times. On the other hand relatively high concentrations coupled with long residence time gave better removal efficiency for organic nitrogen. Phosphate removal though poor under all experimental conditions, was better at low HLRs. In 1 meter saturated and unsaturated soil columns, E2 was the most easily removed estrogen, while EE2 was the least removed. Reducing the thickness of the unsaturated zone had a negative impact on removal efficiencies of the estrogens whereas increased DOC improved the removal in the saturated columns. Better removal efficiencies were also obtained at lower HLRs and in the presence of silt and clay. Sorption and biodegradation were found to be responsible for TCC removal in a 300 mm long saturated soil column, the latter mechanism however being unsustainable. TCC removal efficiency was dependent on the applied concentration and decreased over time and increased with column depth. Within the duration of the experimental run, TCC negatively impacted on treatment performance, possibly due to its antibacterial property, as evidenced by a reduction in COD removals in the column. COD in the 2 meter column under saturated conditions was modelled successfully with the advection dispersion equation with coupled Monod kinetics. Empirical models were also developed for the removal of TCC and EE2 under saturated and unsaturated conditions respectively. The empirical models predicted the TCC and EE2 removal profiles well. There is however the need for validation of the models developed / Netherlands Organisation for International Cooperation in Higher Education (Nuffic) / The Appendix files for this thesis are unavailable online via Bradford Scholars.
28

Sediment oxygen demand in coastal waters

Yung, Kam-shing., 翁錦誠. January 1994 (has links)
published_or_final_version / Civil and Structural Engineering / Doctoral / Doctor of Philosophy
29

Poly(γ-glutamic) acid (PGA) production from confectionery waste using Bacillus species

Rademeyer, Sharon January 2018 (has links)
Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2018. / Approximately 9 million tonnes of food waste is generated annually in South Africa. Its treatment, including treatment of confectionery waste, is costly because of the high chemical oxygen demand (COD) loads; as a result much of this waste is sent to landfill. South Africa’s confectionery industry contributes to a significant proportion of the country’s economy. Among the confectionery waste entering landfills are defective material, expired sweets and returns. This high COD waste can create breeding grounds for pathogenic microorganisms and anaerobic methanogens, causing negative environmental impacts. Part of the Department of Science and Technology (DST) Waste Research, Development and Innovation (RD&I) roadmap initiative is to minimise waste entering landfills by identifying waste sources from which to produce value that will contribute to social and economic growth. Confectionery waste has a high sugar content which can be used for feedstock to bioprocesses. By placing this bioproduction into a waste biorefinery framework, bio-based raw materials can be used to produce competitively priced products with low environmental impact, thereby optimising remediation and value generation simultaneously. Ongoing research at the Centre for Bioprocess Engineering Research (CeBER) at the University of Cape Town has shown that a wastewater biorefinery approach can use wastewater as feedstock for the generation of products of value. Previous studies have investigated potential products of value based on nutrient loads found in wastewater as well as the nature of the product. Among the organisms selected was the Bacillus species, producing the potential product poly-γ-glutamic acid (PGA), an extracellular poly-amino acid when there is an excess of nutrients. Similarly, this product could potentially be produced from sugar-rich waste candy. The aim of this study was to explore the use of hard candy waste as a feedstock for PGA, and Bacillus licheniformis JCM 2505 was selected as it was characterised in terms of the nutrients needed. The most attractive attribute of this strain was that it did not need L-glutamic acid to synthesise PGA but could do so from sugar. L-glutamic acid is costly. Using a cheaper nitrogen alternative would make the process more cost effective. To investigate this potential, the confectionery waste was characterised to identify the nutrients, namely, sugars, organic nitrogen and key trace elements needed for cell function and PGA production. Results showed that the nitrogen content and trace element concentrations were insignificant, as it was determined that the waste consisted mostly of sucrose. This therefore had to be supplemented with a basal medium containing the supplementation needed for cell function and PGA production. The growth of B. licheniformis was profiled in Erlenmeyer shake flasks using candy waste supplemented with the basal medium, with sucrose supplemented with basal medium as a control. The results showed similar trends on candy waste and sucrose.
30

Optimisation of sludge pretreatment by low frequency sonication under pressure

Le, Ngoc Tuan 09 December 2013 (has links) (PDF)
The objective of this work is to optimize high-power low-frequency sonication (US) pretreatment of sludge, and especially to investigate for the first time possible improvements by higher pressure and audible frequency. After a preliminary examination of regular process conditions (sludge conditioning, sludge type, prior alkalization, temperature control, etc), effects of US parameters (power -PUS, intensity -IUS, specific energy input -ES, frequency -FS, etc.) and of hydrostatic pressure (Ph) were specifically looked into, separately and in combination, first under cooling at constant temperature (28°C), then under the progressive temperature rise provoked by sonication. First, it was confirmed that specific energy input (ES) plays a key role in sludge US disintegration (i.e. solubilisation of organic matter) and that temperature rise during adiabatic-like sonication is beneficial through additional effects of thermal hydrolysis and cavitation. At a given ES value, low FS (12 kHz vs. 20 kHz) and high PUS enhance soluble chemical oxygen demand (SCOD) due to more violent cavitation, while hydrostatic pressure gives rise to an optimum value due to its opposite effects on cavitation threshold and intensity. One major result is that optimal pressure depends on IUS (P¬US) as well as temperature profile, but not on ES, FS, nor sludge type. Setting the other parameters at the most favorable conditions expected, i.e. 12 kHz, 360 W , 28 gTS/L, and adiabatic conditions, final optimization was achieved by searching for this pressure optimum and examining sequential procedure to avoid too high temperature dampening cavitation intensity and damaging the transducer. Such conditions with sequential mode and Ph of 3.25 bar being selected succeeded in achieving very high SCOD, but only marginally improved subsequent methanization yield.

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