Providing water and proper sanitation to poor communities by 2015 is one of the United Nations targets for this millennium. In South Africa many communities aspire to waterborne sanitation. However, there is a technology gap for decentralized and sustainable waterborne sanitation systems capable of treating domestic wastewater (Foxon et al., 2006). Although domestic wastewater is more commonly treated using aerobic processes, anaerobic processes may be more appropriate for decentralized applications since they do not require aeration. Research is currently being undertaken to understand the behavior of a combined ABR-MBR unit for treating domestic wastewater. In this study, the anaerobic baffled reactor (ABR) was investigated by analyzing physico-chemical and biochemical data from experiments on a laboratory-scale ABR. This anaerobic reactor was treating complex particulate wastewater made up of sludge from the ventilated improved pit latrine toilets (known as VIP sludge). The main focus of this study was to establish the relationship between the increasing organic loading rates and the effluent characteristics (such as chemical oxygen demand: COD and extrapolymeric substances: EPS). The present work was structured in two parts; in the first part the reactor was operated at constant hydraulic retention time (HRT) without controlling feed characteristics. In the second part, the ABR was operated with step increases in organic loading rates. It was logistically not possible to provide a feed of real domestic wastewater to the laboratory-scale equipment. Consequently, a pit latrine sludge diluted with tap water was used to feed the ABR. This feed was found to have different biodegradability characteristics compared to domestic wastewater. However, the results still give insight into the performance of the ABR and into the treatability of VIP sludge. COD removal ranged from 52 to 80 % depending on the inlet COD. Some COD removal was due to solids retention in compartments, while it was estimated that only 28% of COD removal was due to biological degradation. Soluble extrapolymeric substances (proteins and carbohydrates) which are usually a by -product of anaerobic degradation were higher in the feed than in the effluent despite the increasing organic loading rates. However, more than 50 % of soluble extrapolymeric substances from the influent remained in the effluent and were found (in a parallel project) to influence membrane fouling in the membrane section of the experimental set-up (ABR-MBR unit). Parameters such as pH, conductivity, alkalinity, total and volatile solids were also investigated in this study. The pH decreased slightly from the inlet to the outlet during all runs even though the loading rates were increased. Conductivity increased significantly from influent to effluent with the increasing organic loading rates. Large amounts of total solids were retained in the reactor during the treatment process. Low alkalinity production was recorded during the operation of the reactor. In most cases, the data recorded in this study showed a low biological activity taking place while the reactor was working at room temperatures. Overall, up to 80% of removal efficiencies in terms of total COD and solids were recorded with increasing organic loading rates at constant hydraulic retention time. While these results do not allow the prediction of ABR-MBR performance during the treatment of real wastewater, it was concluded that: Most solids retention occurred in the feed tank. Most COD removal occurred as a result of solids retention and digestion. Loading characteristics did not strongly influence effluent EPS, pH or alkalinity, but did influence COD and conductivity. The relatively low biodegradability of the feedstock indicates that anaerobic digestion is not the most appropriate treatment for VIP sludge. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2010.

A thesis submitted to the Faculty of Science, University of the Witwatersrand in fulfilment of the requirements for the degree of Doctor of Philosophy. November 2016. / This research was directed towards the environmental monitoring and assessment of the most used non-steroidal anti-inflammatory drugs (NSAIDs) which are naproxen, ibuprofen and diclofenac. The work involved the development and application of sensitive techniques for the quantification of naproxen, ibuprofen and diclofenac in the South African aquatic environment. Based on this information, a multi-templates molecularly imprinted polymer (MIP) was synthesized and applied alongside the commercial available sorbent (Oasis MAX) in the solid-phase extraction (SPE) of target compounds from water samples. The extracted compounds were then quantified using high performance liquid chromatography (HPLC). MIP was synthesized by applying a bulk polymerization approach at 70 ͦ C where all target compounds were used as multi-templates. Other reagents used in synthesis were 2-vinyl pyridine, 1,1’-azobis-(cyclohexanecarbonitrile), ethylene glycol dimethacrylate and toluene as functional monomer, initiator, cross-linker and porogenic solvent, respectively. Synthesis of a non-imprinted polymer (NIP) under similar reaction conditions as MIP was carried out with the omission of templates. Techniques employed in characterization of MIP and NIP were Fourier transform infrared spectroscopy (FTIR), Brunauer, Emmett and Teller (BET) method, CHNS analyzer, zeta potential, cross-polarization/magic angle spinning nuclear magnetic resonance spectroscopy, thermogravimetric analysis, differential scanning calorimetry and x-ray diffraction. Monomer-template interactions were investigated using molecular dynamics. The performance of the MIP was evaluated based on its ability to selectively extract target compounds in organic (acetonitrile, acetone, chloroform and toluene) and aqueous media. The extraction capacity of the MIP in organic solvents for naproxen, ibuprofen and diclofenac increased from high polarity to low polarity solvents. In a low polarity solvent (toluene), the extraction capacity achieved for naproxen, ibuprofen and diclofenac were 14.4, 11.0 and 14.0 mg/g, respectively. In this case, the selectivity of the MIP where gemfibrozil was employed as the competing species was evident. Selectivity of the MIP collapsed during the adsorption of naproxen, ibuprofen and diclofenac from water using gemfibrozil and fenoprofen as competitors. This resulted in high extraction efficiencies for target compounds and competitors, however, both gemfibrozil and fenoprofen were easily desorbed from the MIP using weak organic solvent due to lack of molecular recognition. During the binding sites characterization, the best fit of pseudo-second-order implied a chemisorption of all target compounds onto MIP sorbent. The data also fitted well in Langmuir isotherm which meant that the adsorption of target pharmaceuticals occurred on the homogeneous binding sites of the MIP. Optimized adsorption conditions in water such as MIP amount of 50 mg, extraction time of 10 min, sample pH of 2.5 and sample volume of 10 mL were applied for the selective adsorption of naproxen, ibuprofen and diclofenac in contaminated wastewater and river water. In WWTP influent, naproxen recovery was 38%, whereas ibuprofen and diclofenac were 69% and 87%, respectively. MIP was further used as a selective adsorbent in solid-phase extraction (SPE) of three drugs from environmental samples. The selectivity of the MIP in environmental samples was compared to that of the commercially available Oasis MAX sorbent. The application of molecularly imprinted solid-phase extraction (MISPE) reduced matrix effects and improved the sensitivity of the analytical method. In this case, the detection limits for naproxen, ibuprofen and diclofenac were 0.2, 1 and 0.6 μg/L, respectively. When deionized water was spiked with 5 and 50 μg/L of target compounds, recoveries greater than 80% were obtained. Thereafter, the developed MISPE was applied for selected acidic drugs from environmental samples. Environmental samples were collected from urban (Durban) and semi-urban/rural areas (Ladysmith) of KwaZulu-Natal Province in South Africa. The most abundant compound in the environment was ibuprofen. In river water samples from Durban, the maximum concentrations found for naproxen, ibuprofen and diclofenac were 6.8, 19 and 9.7 μg/L, respectively. The maximum amounts found for the same drugs in Ladysmith river samples were generally lower with naproxen, ibuprofen and diclofenac detected at 2.8, 6.7 and 2.6 μg/L, respectively. The same trend was observed in wastewater. Further work on the monitoring of acidic compounds in wastewater was conducted using Oasis MAX as the SPE sorbent prior to HPLC analysis. All target compounds were detected in Kingsburg and Umbilo WWTPs located in Durban surroundings. The influent and effluent concentrations detected were in the ranges of 6.4 to 69 μg/L and 0.6 to 4.2 μg/L, respectively. Further to this, the removal efficiency of the target compounds during the WWTP process in Kingsburg and Umbilo was in the range of 69 to 97%. The extent of pollution in the environment was further assessed by the monitoring of ketoprofen and triclosan in wastewater and river water using SPE with Oasis HLB sorbent and HPLC. Traces of both compounds ranging from 1.2 to 9.0 μg/L were detected in wastewater. The maximum concentrations found in river water were 2.0 and 0.9 μg/L for ketprofen and triclosan, respectively. Overall, the analytical methods implemented in this work were highly accurate, precise and sensitive. The synthesized MIP was highly selective and its application in environmental studies led to the development of a less expensive analytical method. This work also gives the overview of the extent of water pollution caused by acidic pharmaceuticals in various water matrices. / MT2017

Digitized by Kansas Correctional Industries

Thesis (Ph. D.)--University of Queensland, 2003. / Includes bibliographical references.

No description available.

Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on January 11, 2008) Includes bibliographical references.

Thesis (M.S.) in Plant, Soil and Environmental Sciences--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 72-83).

Thesis (Ph. D.)--University of North Texas, Aug., 2007. / Title from title page display. Includes bibliographical references.

Thesis equivalent (M.P.H.)--University of Michigan, 1947.

Thesis equivalent (M.P.H.)--University of Michigan, 1947.