Dissertations / Theses on the topic 'Sewage pollution'
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1
Chan, Yvonne Yik Woon. "Ultraviolet treatments of sewage effluents." Thesis, London South Bank University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261143.
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Lafitte-Trouque, Sandrine. "Enhanced anaerobic digestion of sewage sludge." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369392.
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Lake, Donna L. "Fractionation and characterisation of heavy metals in sewage sludges." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/38078.
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Sweetman, Andrew J. "Organic contaminants in sewage sludges and their fate in agricultural soils." Thesis, Lancaster University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296973.
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Elhmmali, Mohamed Mimoun. "Complementary use of bile acids and sterols as sewage pollution indicators." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245524.
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Bruce, Lorna J. "The effects of heavy metal-rich sewage sludge on Collembola communities in grassland." Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266457.
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Ashworth, Robert Frederick. "The factors determining nitrogen removal from sewage using a gravel bed hydroponic treatment system." Thesis, University of Portsmouth, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305673.
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Hodkinson, Brenden James. "The sewage treatment capability of non-backwash biological aerated filter systems for small communities." Thesis, University of Portsmouth, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368839.
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Biological Aerated Filters (BAFs) are wastewater treatment systems which contain support media for biofilm development and provide oxygen at the base of the reactor to sustain aerobic microbial treatment processes. The aims of this study were to characterise and quantify the treatment capability of non-backwash BAFs used in small sewage treatment works, and therefore establish design recommendations. Three full scale trial BAFs, a field operational small sewage treatment plant, and a full scale aeration testing facility were studied. The trial BAFs, with simulated secondary settlement, provided carbonaceous stabilisation under various hydraulic loadings and airflow rates. Nitrification showed no relationship with airflow rate, but was inhibited at high hydraulic loadings. Sludge production in the BAFs was less at higher airflow rates, due to improved stabilisation of organic solids. Media specific surface area had little effect on treatment performance. Downflow operation generally provided better treatment than upflow operation, with high levels of suspended solids stabilisation, considered a function of longer residence times. The mean BAF residence times determined empirically were considerably shorter than the design residence times, and may have inhibited treatment potential. The oxygen transfer efficiency (OTE) of coarse bubble diffusers was enhanced in a simulated BAF, due to the effects of the support media. Fine bubble diffuser OTE was inhibited by the media. Coarse diffusers may be more appropriate than fine diffusers for small non-backwash BAFs, a function of performance and cost efficiency. A small packaged sewage treatment plant incorporating BAFs produced a well nitrified effluent with reasonable organic stabilisation, and showed little diurnal or seasonal variation in effluent quality. The plant compared well to other small sewage treatment systems, providing treatment in a small footprint. Design recommendations for non-backwash BAFs and small sewage treatment plants incorporating BAFs have been established, based on the knowledge gained during this study. It has been demonstrated that non-backwash BAFs are appropriate for use in small sewage treatment works.
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Wilson, Susan Caroline. "The fate and behaviour of volatile organic compounds and chlorophenols in sewage sludge amended soils." Thesis, Lancaster University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296974.
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Wang, Min-Jian. "The behaviour and fate of chlorobenzenes introduced into soil-plant systems by sewage sludge application." Thesis, Lancaster University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358905.
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Mills, Stephen William. "Sewage treatment in waste stabilisation ponds : physiological studies on the microalgal and faecal coliform populations." Thesis, University of Liverpool, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328437.
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12
Brown, Rachel. "The sub-surface distribution of some heavy metals following sewage sludge injection into grassland soils." Thesis, University of Plymouth, 1994. http://hdl.handle.net/10026.1/2079.
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The use of suitable sewage sludge in agriculture is currently its cheapest disposal option, both in terms of monetary cost, resource utilisation and environmental impact Monitoring of die heavy metal content of the soil after sludge application is required by European Council Du-ective 86/278/EEC, and whilst the behaviour of metals from surface-applied sludge is well documented, the behaviour following other methods of application has received litde attention. The most important alternative land application method cturentiy in use is the subsurface injection of sludge. In this project, field- and laboratory-based experiments were set up to describe the postinjection disttibution of Cd, Cu, Ni, Pb and Zn and the effect on this of: tine design (using die straight tine, side-inclined tine and winged tine), rate of injection (225 m^ ha'-^ and 300 m3 ha"-^), and soil factors ^ H , cation exchange capacity, organic carbon, percentage clay,. Fe and Mn concentration, and redox potential). An assessment of the variability of die injection operation was also important, as account needs to be made of metal distribution and variability in order to delimit an appropriate sampling regime. The results of these experiments indicated that Cu, Pb and Zn are basically immobile, remaining widiin 120 mm of die centte of die original slot location. Tine design was seen to have a significant influence on the pattern of subsurface metal distribution, but neither this,' rate of injection nor soil factors adequately predicted die extent of diis distiibution. Instead, metal identity and concentration widiin the sludge were identified as the most influential factors, in that appreciable quantities of Cd and Ni are leached out of the profile to distances exceeding 300 mm from die sludge, and greater metal concentirations (of the remaining metals) in the injected sludge create distinct gradients in the soil and saturates exchange sites, thus promoting mobility via diffusion, over-riding normal metal chemistry. Of those measured variables that had a secondary effect on distribution, pH, Fe oxide concentration and percentage clay were identified as the most important soil factors.The winged tine was seen to promote soil disturbance and hence metal distribution, and the paraplow to restrict both. In practical terms, these conclusions indicate that the current sampling protocol is inadequate. An alternative regime is suggested.
13
Boyd, David Miller. "FRNA Coliphages as a Viral Indicator of Sewage Pollution in an Estuary." W&M ScholarWorks, 1990. https://scholarworks.wm.edu/etd/1539617616.
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Tennakoon, Nihal Ananda. "Effect of heavy metal contaminated sewage sludge on biological and chemical properties of coniferous forest soils." Thesis, University of Aberdeen, 1993. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU549118.
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A field study was carried out at Ardross forest, northern Scotland where heavy metal contaminated sewage sludge had been applied to a peaty podzol at rates of 500 (low) and 1000 (high) kg N ha-1 before tree (Sitka spruce) planting. Nitrogen mineralisation rates determined by field incubation of sealed cores ranged from 3.7 to 4.5 and 7.3 to 9.4 kg N h-1 over the growing season (May to September, 1991) in soils amended with low and high rates of sludge respectively. For the control soil, to which no sludge had been added, mineralisation rates ranged from 2.4 to 2.9 kg N ha-1. Mineralisation of residual sludge was estimated to be 0.56&'37 and 1.14&'37 in 1991, 8 years after sludge application at the low and high rates, respectively. Soils brought back to the laboratory and repacked according to the field profile enabled microcosm studies to be carried out to further investigate possible changes caused to N-cycling processes in coniferous forest soil due to application of heavy metal contaminated sewage sludge, and to consider possible mechanisms of any such changes. In the microcosm study, the two rates of application of sewage sludge increased N mineralisation. A linear relationship was apparent between N mineralisation and the rate of sludge application. Increased N mineralisation was associated with an increase in active fungal mycelium, biomass N and soil animal population densities. The availability of Cd, Cu, Mn, Pb and Zn was found to be related to the time of the year, with highest availability in Spring and Summer, and lowest availability in Winter. There was no evidence of any adverse effects in terms of heavy metals on the studied biological parameters and mineralisation rates in the field and microcosm studies. Total N, pH and moisture also increased due to sludge application.
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Lucero-Ramirez, Baltazar. "The effects of time and temperature on the fate of pathogens and indicator bacteria during municipal wastewater sludge-mesophilic anaerobic digestion, air-drying, and composting /." Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004325.
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McLanaghan, Stuart Robert Buchanan. "The application and development of life-cycle assessment (LCA) methodologies to processes : a case study of sewage sludge management." Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/11829.
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Engelbrecht, Johannes Frederik Pieter. "Afsterwe van mikroorganismes teenwoordig in rioolwater in die mariene omgewing." Thesis, Cape Technikon, 1990. http://hdl.handle.net/20.500.11838/783.
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Thesis (M.Dip.)--Cape Technikon, 1990The die-off in the marine environment of micro-organisms that are present in sewage was investigated. A literature survey was carried out and studies were done in the laboratory, at an offshore outfall and at a surf-zone outfall. In the laboratory raw sewage was mixed with sea water at known dilutions and the die-off of faecal coliforms, faecal streptococci and coliphage was monitored. At the offshore sewage outfall a tracer, Rhodamine B.was released in the pump station and the distribution of the plume around the diffuser was determined by means of the Rhodamine B concentrations and faecal colifonns counts. At the factory surf-zone outlet the Rhodamine B was injected into the pipeline. Samples were taken at 50 and 100 meter distance from the outlet. Thedie-off of faecal colifonns, faecal streptococci and coliphage was monitored. The following results were obtained: Literature study: (i) Coliforms • Temperatures of 15 QC and lower are conducive to survival while nutrients, at a concentration as low as 2,5 mg/L organic carbon, stimulate growth. A rise in salinity has a negative effect on the organisms. • The T90 value in direct sunlight is <2 hours but vanes considerably in the dark (>35 days). Changes in weather• conditions, sunlight intensity, hours of sunlight, depth and turbidity of seawater and different seasons are the most important factors accounting for the variations in the T90 values. • It is, therefore, important for the initial dilution to be large enough. This will ensure that the bacterial counts conform to the water quality criteria, as the die-off rates in the marine environment are slow and not always adequate, except around mid day. • Faecal coliforms as a single parameter is not considered to be the best indicator of marine pollution. • The 1:4 ratio between faecal coliforms and faecal streptococci for human faeces and 1:0,7 ratio for animal waste are not applicable in the marine environment. The survival of faecal streptococci in seawater is better than that of faecal coliforms and the ratio therefore changes. (ii) Enterococci and pathogens • The T90 value for faecal streptococci is double that of coliforms and also varies in the dark. In direct sunlight any change in sunlight intensity, change the T90 values. • In general the numbers of faecal streptococci and pathogens occuring in sewage are smaller than those of coliforms, but their survival time is longer. This could lead to a situation where the water quality complies with the criteria according to the coliform counts, while a health risk may exist due to th survival of pathogens.
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Pais, Goyache Irene. "DEVELOPMENT OF A CHEMICAL FINGERPRINT FOR DETECTING UNTREATED HUMAN SEWAGE POLLUTION IN SURFACE WATER." Master's thesis, Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/360924.
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Civil EngineeringM.S.Env.E.
Untreated human sewage pollution in surface water is of concern because it contributes to the degradation of aquatic ecosystems and it could be a potential hazard to human health. Also, any pollution of surface water, which ultimately supplies drinking water, may affect the drinking water quality. Improper operation and maintenance of separate storm sewer systems are prominent contributors of untreated sewage to source waters, resulting from illicit connections, leakage of sewers, or cross-connections. This thesis studied anthropogenic markers to track untreated sewage in an urban watershed with separate storm sewer system, under dry weather conditions. The main feature of these chemical markers is their degradation behavior at municipal wastewater treatment plants: some markers are completely removed (labile markers), whereas others show only partial or no removal at all (conservative markers). A set of ubiquitous chemical markers with practical analytical detection limits was selected to exploit the labile vs conservative distinction, and determine if untreated human sewage was discharged from stormwater outfalls. The presence of labile markers alone was not enough to confirm the occurrence of untreated sewage in stormwater outfalls. The concentration ratios between labile and conservative markers from several chemical groups (pharmaceuticals and personal care products, over-the-counter medications, artificial sweeteners, and human metabolites) created a chemical fingerprint of untreated sewage, and it was statistically demonstrated to track untreated human sewage in local stormwater outfalls.
Temple University--Theses
19
Pratt, Catherine, and n/a. "Investigations into Faecal Sterols and E.Coli as Indicators of Sewage and Non-Sewage Inputs into a Subtropical Estuarine Embayment System in South Eastern QLD, Australia." Griffith University. School of Environmental and Applied Science, 2006. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070124.111827.
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Sewage pollution from humans, animal and domestic sources (land and agricultural run-off) are recognized as a major cause of deteriorating water quality along Australia's coastline. Management of water quality has primarily relied on the use of bacterial indicator methods. However the validity and source-specificity of these methods have been met with increasing reservations for several years now. A relatively recent methodology uses a different chemical biomarker approach using 'sterols', a group of compounds related to the common bio-membrane lipid cholesterol and its derivatives. Sterols can offer an additional diagnostic tool to distinguish and discriminate between sources of faecal contamination in marine, freshwater and estuarine environments in both sediments and the water column. This study investigates for the first time, the degradation of coprostanol and selected faecal sterols in 'natural' sediments from a highly mixed (marine and estuarine) sub-tropical environment following a simulated pollution event (primary effluent); the use of faecal sterols as an additional indicator for determining non-point source sewage discharges at popular anchorages in the Moreton Bay and Gold Coast Broadwater system; and the use of sterol ratios in the determination of the fate and transportation of nutrients from a Sewage Treatment Plant (STP) point-source outlet pipe during plant malfunction. The microcosm degradation experiment revealed that faecal and selected sterols are continually synthesised and degraded over time by auto- and hetero trophic organisms within the sediment matrix. Coprostanol was the only sterol to degrade continually, with only minor fluctuations over a time period of two months. Results from this degradation experiment further revealed a sharp decline of coprostanol within the first week. From this it could be concluded that, without any further addition, external inputs of coprostanol are reduced to background levels within this time period. Therefore, removal of coprostanol after six days was 94% and 73% in mud and sand, respectively. The removal of coprostanol was much higher in mud than sand, reflecting a higher level of microbial activity in muddy sediments for assimilation of sterols. The field study undertaken at popular anchorages in Moreton Bay and the Gold Coast Broadwater revealed extremely low levels of sterols and bacterial indicators over both a spatial and temporal scale consistent with a shallow, oligotrophic, highly dynamic sand dominated system. Even though sterols analysed were found at extremely low levels (mostly in the nano-gram range), they were found to be highly correlated and were successful in identifying an unexpected once off pollution event from a point source at Moreton Bay Island. Other than this one incident, both sterol and bacterial levels were consistently low even when anchorages were at full capacity. Thus, sewage from recreational vessels was found to have very little, if any, effect on the water quality at anchorages in Moreton Bay and Gold Coast Broadwater. The point-source study conducted during a local sewage treatment plant malfunction revealed that even though absolute concentrations of sterols did not change during this event, the distribution of sterols within the samples changed, hence changing the sterol ratios. Further, nutrients (mainly nitrogen) can be transported several kilometres by currents, flocculate out of the water column and settle out into the sediment in areas with low tidal and hydrological flushing. There, the nutrients can cause in situ production of sterols in sediments changing sterol ratios. Overall, this study revealed that analyses of sterol biomarkers have the potential to indicate nutrient inputs (such as nitrogen) as well as sewage, post-hoc pollution events at extremely low levels/high dilutions in coastal sediments.
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Pratt, Catherine. "Investigations into Faecal Sterols and E.Coli as Indicators of Sewage and Non-Sewage Inputs into a Subtropical Estuarine Embayment System in South Eastern QLD, Australia." Thesis, Griffith University, 2006. http://hdl.handle.net/10072/366621.
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Sewage pollution from humans, animal and domestic sources (land and agricultural run-off) are recognized as a major cause of deteriorating water quality along Australia's coastline. Management of water quality has primarily relied on the use of bacterial indicator methods. However the validity and source-specificity of these methods have been met with increasing reservations for several years now. A relatively recent methodology uses a different chemical biomarker approach using 'sterols', a group of compounds related to the common bio-membrane lipid cholesterol and its derivatives. Sterols can offer an additional diagnostic tool to distinguish and discriminate between sources of faecal contamination in marine, freshwater and estuarine environments in both sediments and the water column. This study investigates for the first time, the degradation of coprostanol and selected faecal sterols in 'natural' sediments from a highly mixed (marine and estuarine) sub-tropical environment following a simulated pollution event (primary effluent); the use of faecal sterols as an additional indicator for determining non-point source sewage discharges at popular anchorages in the Moreton Bay and Gold Coast Broadwater system; and the use of sterol ratios in the determination of the fate and transportation of nutrients from a Sewage Treatment Plant (STP) point-source outlet pipe during plant malfunction. The microcosm degradation experiment revealed that faecal and selected sterols are continually synthesised and degraded over time by auto- and hetero trophic organisms within the sediment matrix. Coprostanol was the only sterol to degrade continually, with only minor fluctuations over a time period of two months. Results from this degradation experiment further revealed a sharp decline of coprostanol within the first week. From this it could be concluded that, without any further addition, external inputs of coprostanol are reduced to background levels within this time period. Therefore, removal of coprostanol after six days was 94% and 73% in mud and sand, respectively. The removal of coprostanol was much higher in mud than sand, reflecting a higher level of microbial activity in muddy sediments for assimilation of sterols. The field study undertaken at popular anchorages in Moreton Bay and the Gold Coast Broadwater revealed extremely low levels of sterols and bacterial indicators over both a spatial and temporal scale consistent with a shallow, oligotrophic, highly dynamic sand dominated system. Even though sterols analysed were found at extremely low levels (mostly in the nano-gram range), they were found to be highly correlated and were successful in identifying an unexpected once off pollution event from a point source at Moreton Bay Island. Other than this one incident, both sterol and bacterial levels were consistently low even when anchorages were at full capacity. Thus, sewage from recreational vessels was found to have very little, if any, effect on the water quality at anchorages in Moreton Bay and Gold Coast Broadwater. The point-source study conducted during a local sewage treatment plant malfunction revealed that even though absolute concentrations of sterols did not change during this event, the distribution of sterols within the samples changed, hence changing the sterol ratios. Further, nutrients (mainly nitrogen) can be transported several kilometres by currents, flocculate out of the water column and settle out into the sediment in areas with low tidal and hydrological flushing. There, the nutrients can cause in situ production of sterols in sediments changing sterol ratios. Overall, this study revealed that analyses of sterol biomarkers have the potential to indicate nutrient inputs (such as nitrogen) as well as sewage, post-hoc pollution events at extremely low levels/high dilutions in coastal sediments.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental and Applied Science
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Benson, Richard Lynn. "On-line monitoring of water quality parameters." Thesis, University of Hull, 1991. http://hydra.hull.ac.uk/resources/hull:8391.
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Chapter one summarises the development of UK legislation for the protection of the aquatic environment, and highlights current EC legislative requirements for water quality. The need for on-line water quality monitoring and the alternative instrumental approaches to it are discussed, together with the philosophy of "easy care instrumentation" and water industry requirements for online analysers. A simple spectrophotometric FI system is proposed for the on-line determination of a range of water quality parameters. The following chapter details instrumentation used in the FI system, emphasising the solid-state photometric detector. Development of an FI manifold for the determination of aluminium in potable and treated waters is covered in the next chapter. The method, based on complexation of aluminium with pyrocatechol violet is compared with a standard Driscoll procedure. Details of the construction and testing of a fully automated FI instrument are also given. Chapter four describes the development of a modular automated FI monitor with a PC compatible STEbus based computer system. Successful operation of this monitor is illustrated by its application to the determination of residual coagulants (aluminium and iron). Full details of software routines for control, processing and validation are given together with results from a tap water trial for dissolved aluminium. The FI determination of residual iron by its complexation with ferene S, and the application of the optimised method in the STEbus based monitor is detailed in chapter five. In the final chapter the use of on-line FI oxidation procedures for the determination of dissolved organic carbon are examined. The oxidation of a wide range of organic species to carbon dioxide using a silver catalysed persulphate reaction, enhanced with UV irradiation and a stopped-flow procedure is described. The sequential determination of inorganic and organic carbon without separation of the fractions is also investigated.
22
Cravo, Alexandra. "The impact of sewage discharge in Valamoura, Portugal : (water quality and metal accumulation in the soft tissues and shell of Patella aspera)." Thesis, Bangor University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318507.
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Symonds, Erin M. "Viruses Found in Raw Sewage and Their Potential to Indicate Fecal Pollution in Coastal Environments." [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002528.
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Van, Niekerk Corrie Maria. "Nitrogen dynamics in sewage sludge and commercial fertilizer enriched soils." Diss., University of Pretoria, 2004. http://hdl.handle.net/2263/24180.
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This study indicated that sewage sludge could be used as an alternative to commercial inorganic fertilizers. It is common practice in South Africa to use agricultural land for disposal of sewage sludge. The disposal of sludge must however be done in a responsible manner to avoid environmental pollution such as nitrate (NO3-) leaching. In South Africa strict guidelines exist regarding sludge disposal, and a maximum of 8 ton ha-1 year-1 (dry mass basis) sludge may be applied. This value was based on possible NO3- leaching, but no equivalent legislation exists for commercial fertilizer that could result in the same harmful effects. In this study the possible pollution hazard in terms of NO3- leaching from sewage sludge was investigated and compared to commercial fertilizer. An incubation trial was done to determine the mineralization rate of sludge and fertilizer. The rate at which inorganic N, NO3- and NH4+ was produced from sewage sludge was measured during this experiment. Sludge was applied at three different loads: 5, 10 and 20 ton dry ha-1. Commercial fertilizer was also applied on three different levels and each level was equivalent to 30% of the N content of the corresponding sludge treatments. It was found that in the sludge treatments the NH4+ levels immediately increased possibly due to microbial activity. The NH4+ levels reached a maximum on day 7, with a production rate of 14, 26 and 60 mg kg-1 NH4+ for the 5, 10 and 20 tondry ha-1 treatment, respectively. After day 7, the production rate decreased while the NOPlant Production and Soil Science
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Nwabineli, Betty Ivie. "A macro and micro study of the impact of sewage discharges to aquatic environments close to human habitats." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311990.
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Volakos, Nikolaos Panagiotou. "Numerical modelling of wind-induced circulation and pollution transport in the Thermaikos Gulf using a curvilinear coordinate system." Thesis, University of Salford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249011.
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Gough, Mark Adrian. "Characterisation of unresolved complex mixtures of hydrocarbons." Thesis, University of Plymouth, 1989. http://hdl.handle.net/10026.1/461.
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The hydrocarbons of recent polluted sediments, in-reservoir and laboratory biodegraded crude oils, and certain petroleum products (e.g. lubricating oils) often display 'humps' or Unresolved Complex Mixtures (UCMs) when analysed by gas chromatography (GC). Although widespread and often abundant, to date little is known of their detailed molecular composition. Standard chromatographic methods of isolation of model aliphatic and aromatic hydrocarbon UCMs from lubricating oils followed by conventional methods of analysis provided little compositional detail. Thus GC and GC-electron impact mass spectrometry (GC-EIMS) was limited to an estimate of carbon number ranges and to the identification of certain series of 'biological marker' compounds. However, these were well resolved and were estimated to account for <10% of the total detector response. Further analyses were performed by chemical ionisation-MS (CI-MS), probe distillation EI-MS, field ionisation-MS (FIMS), and elemental analysis; yet the information provided by each was limited to a few 'average' molecular types. In view of the limitations of conventional methods of analysis, alternative methods were adopted. These utilised novel chemical and pyrolytic degradations of the UCM hydrocarbons. Chemical oxidation with Cr03 in glacial acetic acid produced reasonable yields of total recoverable material (40-80%). Furthermore, a high proportion were functionalised (>90%), and many resolved, which allowed their identification by EI and CI GC-MS. Surprisingly, the most abundant products of oxidation of hydrocarbon UCMs were straight chain monocarboxylic acids. This appeared to contradict literature consensus on UCM composition, namely a predominance of highly branched and/or cyclic hydrocarbons. However, from literature reported CrO oxidations of hydrocarbons, potential precursor compounds were proposed. These were monoalkyl substituted 'TO-branched acyclic and monocyclic alkanes for the aliphatic UCM and alkyl 'TO-branched monoaromatic hydrocarbons for the aromatic UCM. Proposed precursor UCM hydrocarbons were confirmed by synthesis and chemical oxidation under the same conditions. Thus each of the synthetic candidate UCM hydrocarbons [7-n-hexylnonadecane, 9-(2-phenylethyl)-heptadecane and 9-(2- cyc 1 ohexyl ethyl j--hep tade cane] produced n-acids on oxidation with Cr03- Further correlations were found for products of other synthetic alkanes and less abundant UCM oxidation products. For example, n-alkan-2-ones. iso alkan-2- ones, and 7-methyl--y-lactones could all be correlated with methyl substituted acyclic alkyl linkages on UCM hydrocarbons. The application of chemical oxidation to aliphatic UCMS of varied origin showed the technique has great potential for fingerprinting such samples. GC-MS analysis of a selected series of resolved product compounds (alkyl ketones, -y-methyl--y-lactones) showed good correlations for samples of the sane origin, yet distinct differences for UCHs from different sources. Biodegradation of the three candidate UCM hydrocarbons alongside acyclic isoprenoid alkanes and normal and monomethyl alkanea showed the UCM hydrocarbons were at least as resistant to microbial degradation as the isoprenoid alkanes. In this context it is therefore concluded that the candidate UCM compounds serve as good molecular models for hydrocarbon UCMs.
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Niven, Stewart James. "The origins and occurrence of estrogenic A-ring aromatic steroids in U.K. sewage treatment works effluents." Thesis, University of Plymouth, 1999. http://hdl.handle.net/10026.1/2157.
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There is worldwide concern over the possible estrogenic effects of organic chemicals on a variety of wildlife and indeed on humankind. In the U.K., estrogenic compounds in sewage treatment works (STW) effluents have been implicated in causing the increases in egg yolk protein production observed in caged male trout and other fish species. At the initiation of the present study, few of the estrogenic compounds in STW effiuents had been recognised, although circumstantial evidence suggested that steroidal hormones were primary candidates. Cholesterol is abundant in STW effluents and is the precursor of all steroidal hormones biosynthesised in mammalian systems. Thus, the aim of the present study was to examine the hypothesis that cholesterol might undergo A-ring aromatisation, during sewage treatment, producing estrone and 17β-estradiol via, intermediates such as l9-norcholest-l,3,5(10)-trien-3-ol (NCT). To study this hypothesis NCT was first synthesised via a known route and several of its chromatographic and mass spectral properties established for the first time. NCT itself was found to possess some estrogenic potential determined using an established assay but this was rather weak compared to 17β-estradiol - about 200,000 times less active at the minimum concentration needed to invoke a response. NCT also proved to be a much more hydrophobic compound than, for example, 17β-estradiol with a computed log octanol-water partition coefficient (Kow) of over 9 compared with a log Kow of about 4 for l7β-estradiol. The established analytical properties of NCT were then used to investigate possible NCT formation in sewage. Radiolabelled 14C-cholesterol was incubated aerobically and anaerobically in Semi-Continuous Aaivated Sludge (SCAS), Die Away (DA) or simple stand alone STW simulation vessels. The products of incubation in both aqueous and solid fractions were examined by radio-high performance liquid chromatography (r-HPLC), radio-thin layer chromatography (r-TLC) and radio-gas chromatography (r-GC). Aerobic studies showed that side chain cleavage and A-ring rupture of cholesterol occurred rapidly (~25 % of added activity within 24 hrs) as measured by 14C02 evolution. Gaseous evolution was not monitored from the anaerobic experiments. Most remaining activity was associated with the solids fractions in all experiments. In the aqueous experiments both SCAS and DA systems, r-HPLC revealed rapid production of polar products which were not identified further. r-HPLC also revealed non-polar components of which choIest-3,5-diene, an unknown cholestadiene, a cholestadienol (other than 5,7-dienol), cholest-4-en-3-one and possibly NCT were identified by r-GC in the products of DA experiments. Whilst r-HPLC and r-TLC also revealed several products of anaerobic digestion of cholesterol, no compounds were detected by r-GC. STW effluents from two wastewater plants in the North London area were monitored over 7 months for A-ring steroids and other suspected estrogenic chemicals. Both effluents had previously proved estrogenic to caged fish. Liquid and SPM samples were taken, extracted and analysed by GC-MS. The two main estrogens, l7β-estradiol and estrone were identified from all liquid samples but not in SPM extracts. Generally the concentration of estrone (maximum ca 3 ng Lˉ¹) was significantly higher than that for 17β-estradiol (maximum 1 ng fˉ¹). The third natural estrogen, l6a,l7β-estriol, was identified in all Harpenden effluent samples analysed up to a concentration ca 0.5 ng Lˉ¹. However, estriol was not found in Deephams effluent extracts. The phytoestrogen, daidzein, found in soya based products was intermittently found in aqueous effluents samples from both sites >1 ng Lˉ¹. SPM made up <0.001 % of the effluent. Extracts showed that there was a high percentage of steroidal based material with coprostanol>cholesterol=β-sitosterol>>stigmasterol. NCT was twice identified from SPM taken from Deephams with a concentration of 39 and 136 ng 1ˉ¹ but
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Burton, Timothy Paul. "Public participation : principles and practice : the legal regulation of water pollution." Thesis, University of Hull, 1990. http://hydra.hull.ac.uk/resources/hull:3897.
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The main body of the thesis is a detailed study of the practice of the legal regulation of water pollution, primarily between the period of 1 October 1983 and 31 August 1989, although reference is made to events preceding that period where necessary to provide a full assessment.
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Mahmoud, Huda Mahmoud Abdullah. "Structural and functional diversity of epilithic bacterial communities in streams : effects of pollution." Thesis, University of Hull, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271992.
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McQuaig, Shannon M. "Novel method for detecting human polyomaviruses in environmental waters as an indicator of human sewage pollution." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0012040.
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Farahazad, Maryam. "The problems with water quality standards in Oakland Bay associated with the Shelton sewage treatment plant." Online pdf file accessible through the World Wide Web, 2009. http://archives.evergreen.edu/masterstheses/Accession86-10MES/Farahzad_MTMESThesis2009.pdf.
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Gonçalves, Ana Raquel Calapez. "Multiple-stressor impacts on mediterranean stream communities: responses to water scarcity and water pollution." Doctoral thesis, ISA, 2020. http://hdl.handle.net/10400.5/21198.
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Doutoramento em Restauro e Gestão Fluviais - Instituto Superior de Agronomia / Faculdade de Arquitetura / Instituto Superior Técnico. Universidade de LisboaFreshwater ecosystems are influenced by diverse anthropogenic stressors and natural disturbances producing interacting effects (synergies and antagonisms) often unpredicted based on their independent effects, and thereby represent a major concern to predict ecological changes and develop effective management and restoration strategies. The aim of this Thesis was to assess different responses of key stream biological elements (i.e., biofilms and macroinvertebrates) to the impact of main stressors acting in concert in Mediterranean rivers related with water scarcity and pollution (i.e., flow velocity reduction/stagnation and sewage contamination/hypoxia), using mesocosm approaches and evidences of a case study. In a first part, the effects of flow reduction and oxygen depletion conditions in two seasons were evaluated in macroinvertebrates behavioural and functional responses, conducting to evidences of changes in drift patterns and loss of trait diversity with potential impacts on ecosystem functioning and services. In a second part was investigated how single and combined effects of water flow stagnation and sewage contamination affect primary producers and primary consumers, showing that while stagnant water had an overall inhibitory effect, sewage inputs increased biological responses. Also, stressors combined effect revealed to be unfavourable for some biofilm assemblages (decreasing bacteria and algae diversity) while advantageous to other (increasing fungi diversity). In the last part, flow and water quality variations were followed over time in a Mediterranean urban stream, leading to observations of an impoverished community with low diversity and high abundance of tolerant taxa and resistance traits, which was associated with multiple-stressors patterns of urban ecosystems. Overall it was showed that the effects of representative multiple-stressor scenarios on Mediterranean stream biota are dependent on water scarcity conditions and that reductions on sewage inputs needs to be given priority by stream managers to prevent further degradation of these aquatic ecosystems
N/A
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Renew, Jay Earl. "Novel analytical method development and fate assessment for fluoroquinolone, sulfonamide and trimethoprim antibiotics in engineered water treatment systems." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/19910.
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Wraige, Emma Jane. "Studies of the synthesis, environmental occurrence and toxicity of unresolved complex mixtures (UCMs) of hydrocarbons." Thesis, University of Plymouth, 1997. http://hdl.handle.net/10026.1/465.
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The occurrence of unresolved complex mixtures of hydrocarbons (UCMs) in the aliphatic fraction of marine sediments and organisms from areas impacted by petroleum hydrocarbons is well documented and widely accepted as an indication of fossil fuel contamination. In contrast, the presence of an aromatic UCM is often ignored and environmental concentrations of aromatic UCM hydrocarbons in marine biota and sediments are rarely reported. The aims of this study were to establish the quantitative significance of aromatic UCMs in environmental samples and to assess the toxicological significance of both aliphatic and aromatic UCMs. A reproducible method was developed and validated for the analysis and quantification of petroleum hydrocarbons in mussel (Mytilus edulis) tissue. Emphasis was placed upon development of a method which minimized losses of more volatile, lower molecular weight, toxicologically significant hydrocarbons, without compromising recovery of higher molecular weight compounds which are useful for source identification in environmental monitoring schemes. Analysis of mussels from a small number of U. K. coastal locations indicated that aromatic hydrocarbon UCMs may form a significant proportion (ca 20 %) of the total hydrocarbon body burden of mussels from areas contaminated with petroleum hydrocarbons. Aromatic UCM hydrocarbons were not observed in mussels from relatively uncontaminated areas but concentrations of 430 μg g'' (dry wt tissue) were measured in mussels from heavily impacted areas. Aliphatic UCM concentrations ranged from 7- 3445 μg gg' (dry wt tissue). For the purposes of toxicological studies, a low molecular weight model aliphatic UCM hydrocarbon, 4-propyloctane (4-PO) was synthesised. Two low molecular weight model aromatic hydrocarbons 7- cyclohexyltetralin and 7-cyclohexyl-l-propyltetralin were also synthesised using a modification of the Haworth synthesis. All three target compounds and synthetic intermediates were characterised by NMR, MSandIR. Exposure of M. edulis to 4-PO caused a significant reduction in mussel ciliary feeding activity indicating that 4-PO was indeed toxic as measured by this bioassay. The demonstrable narcotic activity of 4-PO is presumably related to the greater aqueous solubility of branched hydrocarbons compared with similar straight chain hydrocarbons. Further experiments investigating the effect of 4- PO over exposure periods up to 120h provided a unique and detailed insight into the relationship between concentration of toxicant in the gills of M. edulis and observed feeding rate. The established method of mussel feeding rate determination was modified in light of this relationship to produce an " improved rapid and reproducible screening technique. Both of the model aromatic UCM hydrocarbons were also found to be toxic to mussel ciliary feeding activity. This appears to be the first report of investigations into the toxicity of the aromatic UCM and suggests that previous studies have ignored an environmental burden of toxicological significance. Estimates of the tissue effective concentration (TEC50) for the model UCM hydrocarbons gave comparable values with those reported for the effect of other narcotic hydrocarbons upon mussel feeding rate, providing support for the theory that non-specific narcosis occurs at a relatively constant tissue concentration of toxicant. The demonstrated narcotic activity of each of the three model UCM hydrocarbons has extended the molecular weight range of narcotic hydrocarbons studied to date. The results presented herein suggest that a small proportion of low molecular weight aliphatic UCMs and perhaps a greater proportion of aromatic UCMs are of toxicological significance.
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Shrivastava, Vikram. "Creek water quality impacts : irrigation tailwaters and sewage discharges." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0006/MQ44277.pdf.
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Loke, Hing-wa. "Predicted achievement of strategic sewage disposal scheme in enhancement of marine water quality in Hong Kong /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18735423.
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Takwi, Colette Nchong. "An assessment of the management of odour at the Athlone wastewater treatment works, Cape Town." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2788.
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Thesis (MTech (Environmental Management))--Cape Peninsula University of Technology, 2017.¹Odour nuisance is increasingly becoming one of the major environmental problems in various countries across the world, especially odour associated with wastewater (Alfonsin et al., 2015; Schlegelmilch et al., 2005; Gostelow et al., 2001). As a result, the management of odour from Wastewater Treatment Works (WWTW) has become one of the environmental challenges besetting these facilities in recent times. The dispersion of odour across the physical boundary of wastewater treatment facilities presents not only negative environmental impacts to the natural environment, but also constitute a nuisance to surrounding populations. The Athlone (WWTW) located in the urban City of Cape Town with high demographics and adjacent to sensitive communities is thus not immune to poor air quality associated with WWTW activities (Walton, 2005). The population growth due to rural-urban migration has further put severe pressure on the facility and thus worsening the odour problem in the area. As a result, complaints have been received by the City Council from the surrounding communities over the last 20 years. In response to these complaints, the management of the WWTW introduced an odour management system with a particular focus on the use of a biotrickling filter coupled with the use of odour masking sprays. This management intervention was adopted in order to control the odour emitted to the atmosphere from the facility (WWTW). While these measures are said to reduce the prevalence of odour to the surrounding environment, it was, however, not clear whether or not such management interventions have reduced odour emitted from the treatment plant. This research was premised on two postulations as an approach to analyse the effect of the odour management plan adopted by the Athlone WWTW’s management and these are: 1) the perceived experience of odour by the adjacent neighbouring communities and, 2) the understanding of the inherent atmospheric dynamics (such as wind velocity, atmospheric stability, inversion layer and ventilation) which influence odour dispersal in the area. The research project argues that these two factors should be taken into account to ensure that the management of odour is sustainable. It is within this background that the research aimed at assessing the management of odour at the Athlone WWTW and to find out, if at all, the inherent local atmospheric conditions in the area and views of the surrounding communities are incorporated into the management of odour from the plant. The methodological design adopted in the study was case study approach. However, the atmospheric data (wind speed and direction) was obtained from the South African Weather Service (SAWS). These variables were analysed qualitatively and experimentally by the use of wind diagrams to provide insight on 2atmospheric stability conditions, surface inversion and topographical properties, and how these phenomenon influences odour dispersion. The study also reviewed previous odour management reports produced by the Althone WWTW management. This type of data was finally supported by data collected from the community by means of a community survey, face-to-face in-depth interviews and qualitative observation. Some major findings from the study revealed that the local weather of Athlone influences the dispersion of odour – facilitating dispersion in the summer through high wind velocities, while impeding dispersion during winter due to the presence of atmospheric stability conditions. Prevailing odours in this community has led to a general feeling of displeasure amongst community members especially since the management of the treatment plan does not include the local community in the decision-making process. In spite of these, the facility’s management approach was found to be more of a response driven nature even though it is ranked as a high-risk facility.
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Amisah, Stephen. "Impacts of anthropogenic activities on the fisheries of the Don, Rother and Dearne catchments." Thesis, University of Hull, 1998. http://hydra.hull.ac.uk/resources/hull:3797.
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Human uses and abuses of rivers have grown and diversified over the last few centuries with increasing urban development. With increasing population growth, there has been increasing demand for the use of rivers to satisfy a diverse range of human needs including solid waste disposal and the discharge of industrial, sewage and mining effluents. Rivers have been abstracted for agricultural and potable water supply and river channels have been modified for navigation, flood defences and hydro-electric power generation. These modifications to the river system disrupt the fabric of the aquatic ecosystem and diminish its integrity, affecting equally the capacity of fish and other organisms to survive. Fish depend on undamaged interactive pathways to enhance their survival, growth and recruitment.The Don, Rother and Dearne catchment in South Yorkshire and North East Derbyshire has suffered from a legacy of pollution and land contamination that dates back to the Industrial Revolution. These rivers have been grossly polluted from industrial, sewage, and mining effluents and from the disposal of solid wastes in the catchment. Much of the lengths of these rivers were fishless into the mid 1980s.Fish populations in the catchment remain low and species diversity is poor at most locations in the Don sub-catchment. Brown trout and coarse fish species are present in the Don catchment, with the salmonid populations confined to the upper reaches. Most tributaries of the River Don provide brown trout recruits to the main rivers but poor water quality and degraded habitats have prevented the successful colonisation of the waters by the species. Coarse fish, where present, were found at the middle and lower reaches of the river.Fish populations and species diversity in the River Dearne are generally poor due to serious water quality problems. Limited numbers of brown trout and coarse fish were found at few locations in the catchment, reflecting the widespread nature of poor water and habitat quality. The sub-catchment receives diverse discharges from sewage, industry and abandoned mines. This is exacerbated by various pollution incidents, the causes of some of which remain unidentified.The River Rother has low fish population densities, and many stretches of the river are fishless due mainly to poor water quality and lack of suitable habitats. Some tributaries of the River Rother, particularly the River Hipper, Redleadmill Brook and Brookside Beck hold considerable numbers of brown trout. The Rother sub-catchment also receives sewage, industrial and mine effluents which impact on the water quality.The benthic macroinvertebrate fauna of the sites studied were mainly pollution-tolerant taxa with low species diversity reflecting poor water quality. Heavy metal levels were generally low and declining which, possibly, relate to the decline in steel and coal industry in the catchment.A concerted programme to improve effluent discharges from major sewage treatment works and industries serving the catchment area coupled with a decline in the coal, steel and manufacturing industries has resulted in marked improvements in water quality of the rivers. Reductions in ammonia and BOD levels have been achieved since 1991 due mainly to improvements to sewage treatment works. As a consequence the fisheries of the rivers have shown some evidence of recovery. Unfortunately these improvements are localised and the fish populations suffer periodic setbacks because of isolated pollution incidents.Despite considerable efforts by the Environment Agency and its predecessors (the National Rivers Authority and Yorkshire Water), to improve the fish populations through stocking and some habitat improvement measures, the general status of the fisheries remains poor particularly in the Rivers Dearne and Rother. A strategic Aquatic Resources Management Plan (ARMP) targeting the bottlenecks to recovery and improvement in the water quality and fisheries habitat is proposed for the long-term sustainable improvement of the fisheries. Project Concept Notes and Logical Project Frameworks have been developed to address the water quality, habitat and fisheries rehabilitation problem. These constitute draft proposals for which additional information would be needed before projects can be progressed.
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Marshall, Shona. "The structure and functioning of the fish assemblage of the Humber Estuary, UK." Thesis, University of Hull, 1995. http://hydra.hull.ac.uk/resources/hull:3708.
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This study provides an assessment of the fish assemblage of the Humber estuary, using a quarterly sampling interval. Sampling 14 subtidal stations throughout the estuary, and two intertidal sites in the outer estuary, the principal aims of the study were to determine the structure and functioning of the assemblage and the environmental and biological factors influencing the fish distribution.
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Clinch, John Richard. "Remote spectrophotometric water quality monitoring." Thesis, University of Hull, 1988. http://hydra.hull.ac.uk/resources/hull:5897.
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The conventional approach to water quality monitoring is to combine periodic sampling with batch analysis in the laboratory. Such a procedure is both labour intensive and time consuming, there are likely to be sample stability and contamination problems, and the information provided is unlikely to be continuous or immediate. This research focussed on the design and construction of fully automated and portable monitors based on flow injection analysis and incorporating solid state photometric detectors. A novel solid state photometric detector was constructed, incorporating light emitting diodes as the light source, which could be used in conjunction with flow injection analysis. Manifolds were studied for a range of species of interest (phosphate, nitrate, ammonia and aluminium) in the field of water quality monitoring and were optimised for their suitability for continuous use. An automated monitor for nitrate was constructed and long term evaluation trials were carried out at several locations for water quality monitoring. Results are also presented for the use of a nitrate monitor in hydroponic cultivation. An automated monitor was also built for the monitoring of ammonia levels in natural waters, which was field tested on the River Avon (Wiltshire). A manifold was also evaluated for the monitoring of residual aluminium levels in drinking water and is currently being commissioned at a water treatment works in Somerset.
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Sinclair, Kevin J. "The co-disposal of sewage sludge with domestic refuse and potential importance of landfill nitrogen transformations." Thesis, University of Glasgow, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339020.
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Obbard, Jeffrey Philip. "The effect of heavy metals on microbial processes related to nutrient cycling in sewage sludged-amended soils." Thesis, Lancaster University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306430.
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Rivas-Urraca, Cristina. "Environmental speciation of tin and lead by HPLC-ICP-MS." Thesis, University of Plymouth, 1996. http://hdl.handle.net/10026.1/459.
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New methodologies have been developed for the determination of organotin and organolead compounds in environmental samples. Several high performance liquid chromatographic separations of organotin compounds have been tested and the best system (cation-exchange chromatography with methanol and a citrate buffer) employed for the determination of tributyltin (TBT), triphenyltin (TPhT), dibutyltin (DBT) and monobutyltin (MBT) in environmental samples. The coupling between high performance liquid chromatography (HPLQ and the inductively coupled plasma-mass spectrometer (ICP-MS) for this application has been modified to yield limits of detection of 0.44,0.26,1.4 and 0.23 ng. g-' as Sri for TBT, TPhT, DBT and MBT respectively. Different extraction procedures have been tested for the determination of organotin species in samples of environmental interest, such as sediments and biological materials. The values obtained for TBT, TPhT and DBT in the analysis of a mussel candidate reference material, CRM 477, have been incorporated in the certification campaign of this material. A liquid chromatographic separation for trimethyllead (TML) and triethyllead (TEL) has also been developed. Artificial rain water has been analysed for TML. The system proved to be valid for the determination of TML in this sample, even in the presence of high amounts of inorganic lead. Finally, isotope dilution analysis (IDA) was incorporated in the method. Tributyltin iodide (TBTI) and trimethyllead chloride (TMLCI), isotopically enriched in "Sn and "Pb, respectively, were synthesised. The mussel tissue CRM 477 was analysed with IDA-HPLC-ICPMS for TBT. As for the analysis without isotope dilution, the result obtained was incorporated in the certification campaign. The analysis with this methodology gave a better precision in the overall determination than external calibration analysis. Artificial rain water, at two different concentration levels, was analysed for TML with IDA-HPLC-ICP-MS. Better precision and accuracy was obtained for the analysis of this material with this method than when external calibration procedures were employed. IDA-HPLC-ICP-MS has proved to be a valid technique for the analysis of environmental samples. The technique simplifies the procedure, compensates for different sources of variability and, thus, the overall precision obtained in the analysis is improved compared to other calibration techniques.
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Manwaring, Howard Stephen. "The application of neural networks to anodic stripping voltammetry to improve trace metal analysis." Thesis, University of Hertfordshire, 1995. http://hdl.handle.net/2299/14150.
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This thesis describes a novel application of an artificial neural network and links together the two diverse disciplines of electroanalytical chemistry and information sciences. The artificial neural network is used to process data obtained from a Differential Pulse Anodic Stripping (DPAS) electroanalytical scan and produces as an output, predictions of lead concentration in samples where the concentration is less than 100 parts per billion. A comparative study of several post analysis processing techniques is presented, both traditional and neural. Through this it is demonstrated that by using a neural network, both the accuracy and the precision of the concentration predictions are increased by a factor of approximately two, over those obtained using a traditional, peak height calibration curve method. Statistical justification for these findings is provided Furthermore it is shown that, by post processing with a neural network, good quantitative predictions of heavy metal concentration may be made from instrument responses so poor that, if using tradition methods of calibration, the analytical scan would have had to be repeated. As part of the research the author has designed and built a complete computer controlled analytical instrument which provides output both to a graphical display and to the neural network. This instrument, which is fully described in the text, is operated via a mouse driven user interface written by the author.
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Maeng, Sung Kyu. "Effect of a silver-bearing photoprocessing wastewater and silver compounds on biological treatment processes." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/19024.
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Hateley, Jonathan Glyn. "An investigation of heavy metal tolerance and reproduction in Nereis diversicolor with reference to their use for biomonitoring." Thesis, University of Hull, 1989. http://hydra.hull.ac.uk/resources/hull:3577.
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Industrially-derived heavy metals are increasingly responsible for contamination of coastal and estuarine waters. All stages of metal production are sources of contamination, the main contributors being acidic mine drainage waters and smelting works. Other major sources are industrial water discharges, sewage sludge, the atmosphere, shipyard paints and electricity power stations (Bryan, 1984). The most contaminated sites are the rivers and estuaries that directly receive the industrial outfalls. It is a common misconception that metal wastes are simply washed out to sea and dispersed. Estuaries are in fact efficient traps of heavy metals. The scrubbing processes of precipitation, chelation and adsorption onto particulate materials ensure that only small amounts of metals escape to the open sea (Turekian, 1977). The accumulation of heavy metals in estuaries raises the question; at what levels do metals have a detrimental effect on the biota?
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BADAWY, AMIN SOLIMAN. "DEVELOPMENT OF A METHOD FOR THE RECOVERY OF ROTAVIRUSES FROM VEGETABLES AND ITS APPLICATION FOR ROTAVIRUS SURVIVAL ON CROPS." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183832.
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As the shortage of fresh water becomes more and more critical, alternative sources are being sought. The reuse of wastewater has become a viable option, particularly for agriculture and landscaping. However, the possible presence of the enteric pathogens, especially viruses, in wastewater has created concern about potential health risks associated with this practice. If wastewater is used for irrigation it may contaminate vegetable crops which are commonly eaten raw. Also, it may contaminate grass used for golf courses, school yards, and playgrounds where more people may be exposed. Rotaviruses may be of particular concern since they are a cause of infantile diarrhea and gastroenteritis in adults and have been a cause of waterborne disease outbreaks. No information, however, is available about the dissemination and survival of rotaviruses on uncooked food and landscaped areas. This information is necessary in developing criteria for determining safe uses of wastewater for crop irrigation. A method was developed for recovery of rotavirus from the surface of vegetables. The simian rotavirus SA-11, adsorbed onto the vegetable surfaces and effects of various eluents, pH, and exposure time, was evaluated to optimize recovery. The maximum recovery of rotavirus occurred with a solution of 3% beef extract at pH 8.0 after 5 minutes of exposure. Survival of rotavirus SA-11 on lettuce, radishes, and carrots stored at 4°C and room temperature was evaluated. Rotavirus SA-11 was able to survive up to 30 days at refrigeration temperatures and up to 25 days at room temperatures. Rotavirus survived longest on lettuce. The survival of coliphage and enteric viruses on grass was studied during winter and summer outdoors. Coliphage, poliovirus, and rotavirus SA-11 survived on two types of grass during winter and summer from 8 to 40 hours. Human rotavirus survived longer than the other enteric viruses, however, coliphage was more sensitive to inactivation. The occurrence of rotaviruses and enteroviruses in the secondarily treated sewage (activated sludge) was evaluated over a one year period. Total coliforms, pH, and turbidity were also determined. Rotavirus concentrations peaked during Spring and Winter while concentrations of enteroviruses peaked during May, September, and December. No correlation was found between the concentrations of total coliforms, rotaviruses and enteroviruses.
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Day, A. D., J. A. McFadyen, T. C. Tucker, and C. B. Cluff. "Potential of Wastewater for Commercial Barley Production." Water Resources Research Center. The University of Arizona, 2014. http://hdl.handle.net/10150/314419.
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No date on item; authors' manuscript.Experiments were conducted in southern Arizona to investigate the effects of irrigation with pump water and a pump water-wastewater mixture on barley (Hordium vulgare L.) growth, grain yield, and grain quality; soil properties; and irrigation water quality. In 1974 and 1975, on small plot research, barley irrigated with a 50:50 mixture of pump water and wastewater significantly exceeded barley irrigated with pump water alone in plant height, number of heads per unit area, number of seeds per head, seed weight, grain yield, and straw yield. In large field studies conducted from 1970 through 1977, barley irrigated with the mixture had taller plants, more lodging, lower grain volume-weights and higher grain yields than barley irrigated with pump water alone. Soils irrigated with both types of irrigation water had similar pH. Soluble salts (ECx103), exchangeable sodium percentage, nitrate-nitrogen, and extractable phosphorus were significantly higher in soils irrigated with the pump water-wastewater mixture than in soils irrigated with pump water. Water quality analyses showed that the pump water-wastewater mixture had lower total soluble salts, lower nitrate-nitrogen, and higher phosphorus levels than pump water alone.
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Yeomans, William Easton. "The effect of treated sewage effluent (urban wastewater) on the trichodinid (protozoa: ciliophora) communities ectozoic on three-spined sticklebacks, Gasterosteus aculeatus L." Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367184.
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