Dissertations / Theses: 'Water and sanitary engineering'

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D'Costa, Laura. "Development of Source and Treated Water Quality Indicators for drinking water in Canada from conceptual design to methodological development." Thesis, University of Ottawa (Canada), 2008. http://hdl.handle.net/10393/27972.

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In September 2005, Health Canada took on the development of a Source Water Quality Indicator for Canada. The main objective was to develop a methodology by which source water quality could be linked to public health, the environment, society, and economy; and measured, tracked, and reported in the form of an indicator for decision making. A Treated Water Quality Indicator was also introduced to bridge the gap between source water quality and human health. With Federal/Provincial/Territorial and academic support, research into the approach and development of a conceptual design, parameter selection rationale, and two tools for the indicator calculations, along with recommendations for future work were completed. The tools developed included a modified Canadian Council of Ministers of the Environment water quality index calculator, and a Treatability Ranking tool (that determined the complexity of treatment required to achieve safe drinking water). The results of this project are described herein.

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Sipos, Cristian. "Inventory, condition assessment and diagnosis water supply and sewage systems." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99539.

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This project describes a methodology for developing a digitized GIS-based inventory of underground municipal utilities, and recommends an approach for developing a database, which will assist with considerably improved management of buried systems and effective use of limited available resources. The study also discusses the water and sewer infrastructure debt and the total infrastructure debt in Canada. Some other issues related to the Canadian water infrastructure, such as water pricing and consumption patterns, along with the deterioration mechanisms of the underground services, are also discussed. The study focuses on the main services of water supply and sewage systems in any Canadian municipality, which presently are in an advanced state of deterioration. The steps required to develop such an inventory are reviewed and suggestions are made for condition assessment of the system using non-destructive techniques, employing simple methods, as well as more sophisticated tests in critical sectors, where further investigation is required. These methods are also summarily revised.
The underground infrastructure of the McGill Downtown Campus is summarily described; it comprises the various underground features which exist in a small community, e.g. water-supply and sewage system, electrical lines, gas pipelines, telecommunication networks, etc., which are similar with Montreal's underground services, in terms of age, materials employed, workmanship and technologies available over the past 175 to 200 years. The framework for the underground infrastructure inventory is proposed for implementation in a small community such as the McGill Downtown Campus.
The long-term goal of the project is to extrapolate the McGill "model", and to enhance it such that the municipalities in Canada can implement it as a basis for development of GIS-based inventories and condition assessment, and prioritization for effective management of underground services, which include scheduling, financing and implementation of repair, rehabilitation and replacement of underground and other infrastructure.

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Do, Minh T. "Chlorination disinfection by-products in drinking water and risk of pancreatic cancer." Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6258.

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This thesis studied the effect of chlorination disinfection by-products (CDBPs) in drinking water on the risk of developing pancreatic cancer. The study was based on the case-control component of the National Enhanced Cancer Surveillance System. Incident cases and frequency-matched population controls recruited between 1994 and 1997 from six Canadian provinces were used to estimate pancreatic cancer risks associated with exposure to CDBPs. Residence history collected from subjects was linked to two sources of water quality data to estimate historical exposure. The first source provided a lifetime average estimate of known exposure to trihalomethane (THM), bromodichloromethane (BDCM), and chloroform (TCM), while the second provided residence-specific estimates of THM exposure. Adjusted risk estimates were based on the most recent 30 years of exposure with missing data imputed using Observed Control Mean Imputation. Overall, no consistent significant increase (or decrease) in pancreatic cancer risks was observed with 30-year exposure to THM, BDCM, and TCM after adjusting for potential confounders.

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Grosso, Laura Margaret. "Computing collaboration : a study of the potential of model building to facilitate urban water supply planning in selected cities of Zimbabwe, Estonia, and Sweden /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/10804.

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Goh, Jung Hean. "Real time water pipes leak detection using electromagnetic waves for the water industry." Thesis, Liverpool John Moores University, 2011. http://researchonline.ljmu.ac.uk/6013/.

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This project concerns the use of an electromagnetic sensor for the detection of leaks/cracks in water pipes. As old metal pipes corrode they start to become brittle, resulting in the potential for cracks to appear in the pipes. In addition corrosion can build up resulting in a restricted flow of water in the pipe. Using an electromagnetic (EM) wave sensor to monitor the signal reflected from the pipes in real time, provides the necessary information to determine where a leak in the pipe has occurred. Analysis of the reflected signal can provide the operator with information about the condition and position of a leak within the pipe. This is the first time research has been carried using EM waves for leak detection in water pipelines. This project involves the design and construction of an EM sensor operating at frequencies in the range of 240MHz to 560MHz, and at a power of OdBm. The sensor is launched into the water pipeline through any existing hydrant and is moved along the pipeline to check for leaks. The simulation software High Frequency Structure Simulator (HFSS) was used to model the pipe section as a circular waveguide cavity, and also for antenna simulation. The monopole and loop antenna were designed to determine the best antenna for this project. The printed circuit board (PCB) design package Eagle was used to provide the surface mount layout for the sensor, and the PCB board was fabricated by using a computer numerical control (CNC) routing machine. Finally the graphical interface package LabVIEW was used to control the frequency sweep for the sensor and to capture the data from the sensor. Based on the findings of this project, the EM wave sensor could be used to determine a leak up to a 0.9 correlation limit using low cost RF electronic devices.

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Banat, Fawzi Ahmed. "Membrane distillation for desalination and removal of volatile organic compounds from water." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28670.

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Membrane distillation, a process in which vapor from a liquid feed passes through the pores of a hydrophobic membrane, was investigated as a possible technique for desalination and for the removal of ethanol, acetone and benzene from water. Three different membrane modules were used in the experiments examining the impact of operating variables upon permeate flux and quality. A mathematical model was developed and validated for the membrane distillation process.
In the desalination study, two modules with built-in condensing surfaces were used for conducting experiments on flat membrane sheets. The quality of the permeate, quantified by conductivity measurements, and the permeate flux were monitored as feed concentration, feed temperature, feed flow rate, cooling temperature, and cooling water flow rate were varied. The effect of the distance between the membrane and condensing surface was investigated by adjusting the air gap within one of the modules. The feed streams tested included sodium chloride solutions and artificial seawater. The membrane materials used were PVDF and PTFE. At optimal conditions, fluxes as high as 26 kg/m$ sp2$hr were obtained. In all experiments, the rejection factor was above 95.5%.
A flat-sheet cross-flow module was used to study the separation of dilute solutions of ethanol and acetone. The same operating parameters tested in the desalination experiments were varied for ethanol and acetone feeds. The upper feed concentrations tested were limited by the risk of membrane wetting to 10 wt% ethanol and 6 wt% acetone. Within the feed temperature range of $40 sp circ$C to $70 sp circ$C, ethanol selectivities of 2 to 3.5 and acetone selectivities of 2 to 6 were achieved. The maximum fluxes obtained were 2.15 kg/m$ sp2$hr for ethanol permeate and 2 kg/m$ sp2$hr for acetone permeate.
A mathematical model, based on first principles of heat and mass transfer, was developed and validated on the desalination, ethanol, and acetone experimental data. Good agreement between experimental and predicted values was obtained with the model version incorporating temperature and concentration polarization.
The possibility of using vacuum membrane distillation for treating water contaminated with volatile organic compounds was investigated by using benzene as a model compound. An experimental unit with polypropylene membrane tubes fitted within a polypropylene shell was used in the tests. Dilute benzene solutions were pumped through the lumen of tubular membranes while vacuum was applied to the shell side. The data obtained by varying operating conditions was analyzed in terms of the overall mass transfer coefficient based on the film theory. A comparison between the effectiveness of membrane distillation and air-stripping was drawn based on a published case study. The experimental unit with tubular membranes failed to compete but extrapolations to higher membrane contact areas showed promise for hollow fiber modules.

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Kin, Kon-Tsu 1964. "Oxidation of trace organic impurities in ultrapure water by UV and ozone." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/282177.

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In this dissertation, the chemical oxidation of trace organic impurities by the treatment of UV light alone, ozone alone, and the combination of UV light and ozone in ultrapure water is discussed. Eighteen model compounds are chosen as the representative organic contaminants. Significant synergistic removal effect by the oxidation of the combination of UV light and ozone has been observed on all model compounds except for trichloroethylene, benzoic acid, and methionine. The removal efficiency by the oxidation of the combined treatment is observed to be greater than that by the oxidation of UV light alone or ozone alone for all model organics. Based on the same injected amount of contaminants over a given period of time, it is shown that the amount of leftover material after one cycle in the loop in a run with ozone injection is lower than that in a run without ozone injection for most compounds. The photolytic ozonation improves the TOC removal efficiency not only on the UV unit, but also on the loop removal performance. The chemistry, advantages and disadvantages of all those three oxidative methods are discussed. The mechanisms of oxidative reaction for the UV/ozone interactions and of ion exchange in the deionized tank are proposed. The rate coefficient of each reaction for model compound is determined by fitting the model prediction to the experimental data. The metrology for modeling the whole ultrapure water system has been established. The mathematical derivations for that metrology are given. For the purpose of paving the road for the reuse of rinsing wastewater, three cases simulating TOC dynamic responses are discussed, and the chemistry between HCl and organics under the treatment of UV light alone is studied. The combined UV/ozone reaction has been proven to be a better way in removing organic contaminants in terms of particles population number density. The mathematical equation of particle size reduction with its breakage rate and fragmentation distribution function is proposed and validated with the experimental data. It is concluded that the surface erosion is the pathway of size reduction when organic particles are oxidized.

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Glanvill, Sarah Jane Marie. "Atmospheric corrosion of AA2024 in ocean water environments." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8554/.

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Observations of atmospheric corrosion on aluminium alloy AA2024-T3 were made within droplets of NaCl solution and simulated ASTM ocean water. High speed in-situ synchrotron X-ray tomography has been used to observe the initiation and propagation of corrosion sites. Tomographic scans had a temporal resolution of 300s per full tomographic scan, providing a non-destructive visualisation of corrosion. Sites initiate at numerous surface morphologies, including at intermetallic inclusions, under surface deposits and salt crystals, and also at sites with no obvious micron-scale microstructural features. It was observed that corrosion sites grow discontinuously and inhomogeneously when conditions are constant, consistent with bursts of dissolution followed by some repassivation. The nature of corrosion products was investigated with Raman spectroscopy and EDX. The dominant corrosion product was Dawsonite for both droplet solutions, however the distribution of corrosion products differed between the two types of droplet. NaCl droplets spread more, resulting in fewer, larger corrosion sites. ASTM ocean water droplets showed multiple small corrosion sites within the droplet owing to the presence of Hydrotalcite around the droplet perimeter. Corrosion development under wet-dry cycling conditions was different for NaCl and ASTM ocean water droplets. Under NaCl droplets, no growth or initiation was observed during “dry” phases. However, ASTM ocean water remains partially wet in “dry” periods as some of the salt constituents in ASTM ocean water remain hydrated. As a consequence, corrosion site growth is able to continue.

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Junaidi, Haroon. "Optimized solar water heater for Scottish weather conditions." Thesis, Edinburgh Napier University, 2007. http://researchrepository.napier.ac.uk/Output/3799.

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The ICSSWH (Integrated Collector Storage Solar Water Heater), apart from being the oldest is also the most economical means of solar water heating. The effect of modifications in the collector geometry has frequently appeared in the literature, and over the time, has resulted in different designs. These designs differ mainly on the site of installation as well as the target application. A novel design created by Professor T Muneer at Napier University, utilizes fins inside the storage tank to improve the heat transfer. The reported field tests of the fin type ICSSWH have indicated a 10 % improvement in the solar fraction compared to unfinned. As ICSSWH is the lowest cost, it presented a possible solution for the Scottish market where Energy Saving Trust estimates that 50% of hot water demand of a household can be met through solar water heating. In the present research program, two prototype collectors (one with- and one without fins) were fabricated at Napier University by the author. The collectors were then tested in the laboratory on identical experimental schemes to determine their respective performance. Simulations based on analytical modelling were then undertaken, using numerous experimental data for validation that were obtained during the course of the present work. A high degree of conformance was noted between the two. Furthermore, for a deeper insight, Computational Fluid Dynamics (CFD) analysis was performed. This research focuses on the qualitative and quantitative assessment of the heat transfer due to the fins. The difference in the performance with respect to the change in tilt angle was also studied. This study can therefore be utilised for developing solar water heating systems for any given location. Note that there is an intrinsic link between the latitude and inclination angle of the collector plate. The nocturnal loss from the collector is the principal factor that has inhibited the wide spread use of the ICSSWH. The remedies to abate this problem have therefore been attempted. In addition to that, the collectors have to be integrated with the domestic hot water supply system and plumbing considerations have to be incorporated within the overall design. The supply circuits were worked out and the measures for freeze and boil protection were devised. The optimization of any system is an intrinsic task particularly when several variables are involved. On the basis of the obtained results from simulations and experiments, the influential design variables were identified. The values for these variables which lead to the optimal design in terms of thermal performance were assessed while keeping the overall manufacturing cost of the collector as low as possible. Recommendations for future work have also been presented.

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Xie, Mingyu. "Model predictive control of water quality in drinking water distribution systems considering disinfection by-products." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7207/.

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The shortage in water resources have been observed all over the world. However, the safety of drinking water has been given much attention by scientists because the disinfection will react with organic matters in drinking water to generate disinfection by-products (DBPs) which are considered as the cancerigenic matters. Although much research has been carried out on the water quality control problem in DWDS, the water quality model considered is linear with only chlorine dynamics. Compared to the linear water quality model, the nonlinear water quality model considers the interaction between chlorine and DBPs dynamics. The thesis proposes a nonlinear model predictive controller which utilises the newly derived nonlinear water quality model as a control alternative for controlling water quality. EPANET and EPANET-MSN are simulators utilised for modelling in the developed nonlinear MPC controller. Uncertainty is not considered in these simulators. This thesis proposes the bounded PPM in a form of multi-input multi-output to robustly bound parameters of chlorine and DBPs jointly and to robustly predict water quality control outputs for quality control purpose. The methodologies and algorithms developed in this thesis are verified by applying extended case studies to the example DWDS. The simulation results are presented and critically analysed.

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Tapah, Boris Fotso. "Processing of organic waste by catalytic supercritical water gasification." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/4752/.

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The results of the degradation of glycerol in supercritical water show that conversion of pure glycerol (58 % at 550 $^0$C) without a catalyst can be achieved, but complete conversion of pure glycerol over Fe$_2$O$_3$+Cr$_2$O$_3$ or Fe$_3$O$_4$ catalysts (at 550$^0$C, 250 barg, <15 wt% feed concentration, 10.1 g and 4 mm catalyst particles) can be reached. Crude glycerol conversion decreases from 100 to 67 mole% and 100 to 74 mole% over the same catalysts and conditions. Hydrogen yield was as high as 61 mole% and 49 mole % when crude glycerol was gasified over Fe$_3$O$_4$ and Fe$_2$O$_3$+Cr$_2$O$_3$, respectively. 64 mole% of syngas was obtained with minimum 4:1 mole ratio of H$_2$:CO. Hydrocarbon yields (69 mole% for ethylene and 22 mole% for methane) were obtained and this decreased with temperature as resulted of thermal cracking. Small amounts of char (<3.1 wt%) and carbon deposition on the catalyst surface and inside the reactor wall was observed. Prolonged exposure of Fe$_2$O$_3$+Cr$_2$O$_3$ to 172 h on-stream under supercritical conditions resulted in fragmentation of the surface from metal sintering, which reduced activity for H$_2$ production. 42 mole% of hydrogen was obtained from 2 wt% digestate gasification at the same conditions.

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Wood, Georgina Victoria. "Water literacy and citizenship : education for sustainable domestic water use in the East Midlands." Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14328/.

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In Britain, projected population rise and climate change threaten future water availability. UK water companies run education programmes to encourage more efficient usage, but these tend to focus on primary schools and adults, missing the opportunity to engage secondary school pupils as the next generation of homeowners and bill payers. Educational interventions also traditionally follow the theory of rational choice, envisaging learners as able to change their attitudes and behaviours in accordance with newly acquired information. Sociological research on social practices and ordinary consumption, however, sees water as playing an inconspicuous role in daily domestic activities. Technological infrastructure and prevalent social norms mould behaviour and limit the ability of water users to alter their consumption. This interdisciplinary thesis attempts to break the impasse between works from educational and sociological perspectives, using the theoretical lens of water citizenship. A review of current water education provision in the East Midlands region was undertaken, and a school-based study involving questionnaires, focus groups and exploratory lessons around water. The young people involved in the study tended to show ambivalence towards water conservation, despite general pro-environmental motivations. While some teenagers perceived they were ‘doing their bit’ for the environment, this tended to be limited to accepting and invoking ‘water saving tips’, and many teenagers eschewed water conservation altogether. These findings indicate that innovative educational programmes are needed to raise the standard of water literacy in the UK. This thesis argues firstly for making water use more ‘visible’ in daily activities, by deconstructing the routines and habits that use water, and by recognising the influences that social norms exert on water use. Secondly, it argues that educational initiatives for water literacy could develop young people’s sense of citizenship and responsibility towards water resources by connecting personal actions to impacts at local, national and global scales.

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Sutherland, Karen Ann. "Biological treatment of sulphide concentrator recycle water and effects on flotation." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61338.

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The objective of this study was to determine the effect of biological treatment, using a trickling filter, on recycle water from a sulphide concentrator. Activated carbon (AC) treatment was studied for comparative purposes.
Both biological AC treatment increased the recovery of chalcopyrite in a single mineral microflotation test, from approximately 5.5% to 14.4% and 7.2% respectively. However, major differences were observed between various samples when comparing the number and types of bubbles produced during frothing tests. As expected, the number of bubbles produced per given volume decreased following AC treatment, approaching that of tap water. However, after biological treatment, the number of bubbles was increased. It is suspected that the changes produced by biological treatment in the recycle water might produce organic matter more surface active than that initially found in the wastewater.

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Khawam, Walid. "Water demand management in the Caribbean : a case study of Barbados." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81544.

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Water demand management attempts to balance the supply of and demand for water by controlling the competing water demands. It realizes the change by influencing peoples' behavior with respect to water use. Water demand management (WDM) is necessary in water scarce regions like Barbados. The Government of Barbados has recognized the need for WDM as demonstrated by the implementation of measures such as universal metering and water pricing.
This research looks at the impact of water pricing and metering on residential water use in Barbados. Econometric demand models of residential water use are developed to assess the potential of pricing policies to conserve water. Price elasticities between -0.18 and -0.93 were obtained suggesting that pricing policies can be used to reduce and control residential water consumption in Barbados. The results of the models are then used to investigate the impact of different rate structures on water use and revenue generation. It is predicted that a 26% decrease in water demand and a 52% increase in revenue collected from water bills would be achieved if the 1997 proposed water rate increase is implemented. In addition, results indicate that water production decreased by 12% from 1997 to 2000, coinciding with the implementation of the Universal Metering Program. However, per-capita consumption has been on the rise in recent years suggesting that metering must be accompanied by a substantial increase in price to encourage water conservation.

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Price, Robert. "A study of hybrid clarification-filtration processes for potable water treatment." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/12410/.

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This research investigates the removal of natural organic matter (NOM) from low turbidity waters by optimising an integrated coagulation and membrane filtration process. In conjunction with a regional water utility, the feasibility and operability of pre-coagulation with ultrafiltration membrane units, is investigated at both the fundamental and applied levels. The pH of coagulation greatly affects the growth of flocs. Although flocs are produced over the range of pH values, there is a significant improvement in performance at the optimum pH. The results show that for ferric sulphate, the optimum pH value for coagulation was 4.8; for ferric chloride the optimum pH value was 5.0; and for alum the optimum pH value was 6. Manipulation of the mixing regime during orthokinetic flocculation allows control of the final floe size. A high shear rate (447 s-1) induces greater particle collision and micro-floc formation, allowing an increased rate of growth during slow mixing. A mixing regime of 60 seconds rapid mixing (shear rate G= 447 s-1) followed by 3 minutes slow mixing (shear rate G= 20 s-1) is required for flocculation of the NOM and adequate enmeshment and removal of excess iron. Experiments conducted with the optimised coagulation regime and a Norit hollow fibre ultrafiltration membrane, operated in dead-end mode, leads to significant fouling. The results for the submerged Zenon ultrafiltration membrane also indicated membrane fouling, when the coagulation regime was optimised for NOM reduction and iron removal. Changing the coagulation regime altered the level of membrane fouling. It can be concluded that the optimum coagulation conditions in conventional water treatment are not always the optimum conditions for coagulation with ultrafiltration treatment and the unconventional coagulation conditions can be much more effective, than the conventional ones, in the context of membrane filtration, depending on the raw water characteristics.

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Grassie, Tom. "Optimisation of fluid-flow in a flat plate solar water heater." Thesis, Edinburgh Napier University, 2001. http://researchrepository.napier.ac.uk/Output/3862.

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Di, Bonito Marcello. "Trace elements in soil pore water : a comparison of sampling methods." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/10123/.

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This thesis examined a range of methods for sampling soil pore water to investigate the chemistry of trace elements. In particular, the study assessed whether Rhizon samplers, centrifugation, high pressure squeezing and soil suspensions in simulated pore water can be viable approaches for obtaining representative samples of equilibrated soil pore water. Results for metal solubility and speciation were interpreted in terms of both soil morphological effects on trace metal dynamics and artefacts introduced at various stages during sample preparation and handling. The main soil used in the study was an organic-rich sandy silt from a site which has served as a sewage re-processing facility for almost a century. This soil was chosen because of its importance as a long-term repository for metal-enriched sludge applied to arable land, providing a suitable medium on which to study trace metal behaviour. Pore waters were extracted and analysed for major and trace cations and anions, pH, Dissolved Inorganic Carbon (DIC) and Dissolved Organic Carbon (DOC) at two different temperatures (5 degrees Celsius and 15 degrees Celsius), in order to evaluate the extent of bacterial activity, organic decomposition and their consequences on solute composition, during pore water extractions. Speciation was estimated from analysis of pore water chemistry using two software packages (PHREEQCi and WHAM-VI). Pore waters showed different ranges of concentration between the various methods. Different mechanisms and/or chemical reactions were involved during the different extractions; a range of processes was identified, mainly dominated by metal complexation by humus acids and redox reactions. Results revealed that the soil studied was able to partially buffer the free ion activities of the metal ions in pore water with increasing dilutions, but demonstrated virtually no ability to buffer DOC. Identification of the source (i.e. location of pore space) of water extracted was also investigated using water with different isotopic composition (18O/16O). Evidence showed that centrifugation was not able to differentiate between more and less mobile water at FC conditions, rather enhancing the mixing between the two pools of water (native and labelled) by and apparent process of 'infusion'. By contrast, Rhizon samplers appeared to sample water preferentially from the more accessible pool (extra-aggregate), which proved to have a composition showing incomplete mixing with the native water. The results also suggested that mixing of the two pools was rather fast and that was almost completely attained prior to pore water extraction. The study established that the most important factors affecting pore water chemistry during extraction are the conditions to which the samples are exposed during the extraction process. For these reasons Rhizon samplers should be used as a disposable device, and are only applicable for use in high soil moisture soil contents. In contrast, they present no 'side-effects' (providing enough equilibration time) if M2+ (free ion activity) were needed as opposed to Msol (total metal concentration in pore water), as often required in environmental studies. Centrifugation is optimal for bulk solution studies, or when homogenisation represents a key experimental point; targeted studies are also possible. Soil squeezing is subject to severe limitations in the case of prolonged extractions of biologically active soils, due to the effects of anaerobism. Squeezing should only be used for 'fast' extractions of soils. Finally, batch extractions are well suited to studies on M2+ equilibria, but more studies are needed to clarify the effect of soil: solution ratio on metal and DOC solubility.

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Skuce, Rebecca L. "Bacteria-mineral-nanoparticle interactions in water and wastewater." Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/6153/.

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With a rising demand for nanomaterials and their continual increase in production, the release of nanoparticles (NPs) into the environment is inevitable (Petosa et al., 2010). Problematically, NPs can have a wide range of toxic effects, which are exacerbated by their size (at least one dimension smaller than 100 nm)(Engineering., 2004). Detrimental effects include brain, intestinal and respiratory injury, delayed embryonic development, DNA damage which ultimately lead to increased mortality (Trouiller et al., 2009), (Handy et al., 2008). Natural and manufactured NPs also have the ability to bind and transport chemical pollutants, thus enhancing their toxicity (Moore, 2006). While an array of techniques are available for in situ remediation of numerous groundwater contaminants, there are currently none for in situ remediation of nanoparticles. This fundamental technology gap means we are poorly prepared to deal with nanoparticle pollution events. The aim of this PhD was to develop mechanisms to immobilise and remove nanoparticles from water and waste water in order to prevent the transport of nanoparticles to sites where they have the potential to cause harm. Experiments conducted demonstrate the potential of microbially mediated mineral formation to immobilise nanoparticles from water. The ureolytic bacteria Sporosarcina pasteurii was used to induce calcium carbonate precipitation in batch and column experiments. Nanoparticle immobilisation was tested as a function of nanoparticle size and surface charge. The results demonstrate the successful immobilisation of negatively charged nanoparticles (both large and small, 150 and 35 nm respectively), while failing to remove positively charged nanoparticles from solution. In order to capture positively charged nanoparticles a second mineral, struvite, was tested. The precipitation of struvite successfully immobilised positively charged nanoparticles. However, in comparison to the calcite precipitation experiments the removal of positively charged nanoparticles was found to be pH and ionic strength dependant. Finally, the ability of Bacillus subtilis, a common groundwater bacterium and wastewater treatment biofilm to adsorb and remove nanoparticles from solution was examined. Here both biosorbent materials were highly efficient at removing positively charged nanoparticles from solution whilst negatively charged nanoparticles remained in suspension. The research presented here demonstrates that microbially induced mineral precipitation may be used as a tool to immobilise nanoparticles from contaminated groundwater. In addition, bacteria and wastewater treatment biofilm were found to be highly efficient biosorbents of positively charged nanoparticles. These findings hold implications for the fate and transport of nanoparticles through environmental systems and wastewater treatment plants.

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Cappelluti, Mauro Davide. "Nanostructured materials for water purification : synthesis, insights and performance evaluation." Thesis, University of Glasgow, 2018. http://theses.gla.ac.uk/9100/.

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Membrane filtration and Advanced Oxidative Processes (AOPs) are among the most efficient and cost-effective methods employed in water purification. A system to integrate the two methods using photoactive colloidal particles was studied in this thesis, with the final purpose of overcoming membrane fouling, one of the main issues occurring in filtration processes. The production of nanostructured TiO2 microparticles through a simple and extremely rapid synthesis and an easy method to assemble a multifunctional coating, integrating inorganic particles on filtration membranes, were targeted as the most promising solutions from the technological and environmental point of view. The control of microwave-assisted heating applied to hydrothermal treatments, a relatively recent synthetic method, allowed the production of nanostructured mesoporous spherical TiO2 particles, bringing the synthesis to the minute scale, extremely rapid compared with conventional heating, and achieving products otherwise difficult to obtain without the help of surfactants or templating agent. The as-synthesised particles showed photoactivity under visible light, with rate of specific reactions (selective de-ethylation) 4 times higher compared with commercial photocatalysts. Furthermore, the particles were modified to extend the limited intrinsic absorbance of TiO2 in the visible light, with promising results given by formation of stoichiometric defects (in particular oxygen vacancies) through annealing under vacuum. This treatment allowed the achievement of comparable or even higher performance in photocatalytic degradation of rhodamine B with respect to commercial TiO2 photocatalysts, including Aeroxide P25, with degradation rate towards organic molecules (rhodamine B) of even 60-70% after 1 hours, compared to the 25% of P25. The production of a multifunctional coating for water treatment by integration of colloidal and nanometric TiO2 particles has been also studied. A simple technique to integrate TiO2 nanoparticles onto different substrate, in particular filtration membranes, was developed by simple electrostatic interactions involving the use of polyelectrolytes, water-soluble charged polymer forming organised layers when assembled in a macromolecular structure defined as polyelectrolyte multilayers (PEMs). Electrostatic assembly was applied as an environmentally friendly technique to anchor nanoparticles (P25) on different surfaces, transferring their properties to these. In particular, the application of TiO2 particles conferred hydrophilic and superhydrophilic to a relatively hydrophobic surface (Mylar) by controlling the multilayer assembly conditions, in particular the ionic strength of the polyelectrolyte solutions. The achievement of superhydrophilic behaviour on the treated surfaces, with contact angles below 15° on Mylar surfaces, and the possibility of removing fouled active layer from a membrane replacing it with a newly generated one can be both implemented as potential antifouling strategies in water treatment.

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Fendi, Karwan Ghazi. "Genetic algorithms and GIS data for decision making in planning water distribution networks." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/14103/.

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This thesis is concerned with the optimal design of Water Distribution Networks (WDNs). The design involves finding an acceptable trade-off between cost minimisation and the maximisation of numerous system benefits. The primary design problem involves cost-effective specification of a pipe network layout and pipe sizes in order to satisfy expected consumer water demands within required pressure limits. The design of a WDN has many variable parameters such as position and size of the water sources, position and the size of the pipes and position of the treatment plants. However, the layout is constrained by the location of existing facilities such as streets and buildings and other geographic features. The total costs may consist of the cost of network materials such as pipes, construction works and system operation and maintenance. The problem may be extended to consider the design of additional components, such as reservoirs, tanks, pumps and valves. Practical designs must also cater for the uncertainty of demand, the requirement of surplus capacity for future growth, and the hydraulic reliability of the system under different demand and potential failure conditions. The thesis reviews the literature related to water distribution networks, their design and optimisation. It then presents a Genetic Algorithm (GA) formulation to assist in developing the design of a water distribution network. The main aim of this research is to investigate the possibility of combining GAs and GIS in the design optimisation. A decision mechanism is developed which enables the model to reach a meaningful solution and provide a practical design technique for WDNs. The aim is also to provide an experimental analysis of the combined GA and decision mechanism to solve the problem in hand and to assess the robustness of these techniques when applied to different instances. An initial prototype model is presented for the design of a WDN which is used to determine the necessary features of the 'final' model. These features include the world in which the model will be built, the design of the fitness function, chromosome representation, and GA operators. The research mainly concluded that the initial model prototype was useful to determine the necessary features and to produce the final model which enables a variety of necessary factors to be explicitly included in the design of WDNs. This initial model suggested that the final model should include the decision mechanism, which is a matter of policy management and hydraulics, and hydraulic principles which allowed to compare the behaviour of different parameters and to simulate the functioning of the network under different scenarios. Water allocation and distribution policies can be applied according to the importance of the demand area and the ability of the system to deliver sufficient water amounts. These policies link essential hydraulic and institutional relationships as well as water uses and users and allocation decision-making process. It was also found that the representation of the world layout is important. The world is described in GIS in terms of models that define the concepts and procedures needed to translate real-world features into data. The important aspects in the chromosome representation are the node positions, the links. In this case, a chromosome must contain the three-dimensional node coordinates, the connection between nodes, the head required to pump the water. The best model parameters were extracted to be used in real-life situations. The result of tests on an example world demonstrated that the model was successful, and the potential exists for the use of this formulation in more complex and real-world scenarios.

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21

Russell, Sarah. "Mercury in water, porewaters, sediments and fish from the Medway Estuary, Southeast England." Thesis, University of Greenwich, 2006. http://gala.gre.ac.uk/6287/.

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This research aimed to investigate the distribution, mobility and potential bioavailability of mercury in the Medway Estuary, Kent, UK, and the impact of feeding regimes on mercury concentrations in the food web, as well as the importance of liver as a storage organ for mercury within fish. Surficial sediment mercury concentrations were typical of an industrialised estuary, ranging between 18-1302 µg kg-1 (dry weight). Three sediment hotspots contained mercury concentrations which are likely to cause adverse affects to organisms. Porewater mercury concentrations ranged between <0.01-1.75 µg L-1, and were not correlated with mercury in the solid phase. The lowest partition ratio between mercury concentrations in sediment and porewaters was observed at four locations in the mid-stream and towards the mouth of the estuary (log Kd = <2). At these locations a greater fraction of total sediment mercury (sediment plus porewater) is likely to remobilise and potentially become more bioavailable. Mercury porewater concentrations are elevated in comparison with overlying waters, suggesting a diffusive release of mercury from the bottom sediments to the water column. The calculated diffusive flux was 6 kg year-1, demonstrating that mercury is mobile in this system. Mercury in sediment core samples ranged between 382-1888 µg kg-1 (dry weight). Dredging the Medway would release mercury from these more contaminated deeper sediments into overlying water, thus having potentially ecotoxic consequences. Within the cores, methylmercury concentrations ranged between 0.3-0.8 µg kg-1 (dry weight) and organomercury ranged between 2-48 µg kg-1 (dry weight). Mercury concentrations in fish flesh ranged between 0.01-0.63 mg kg-1 (wet weight), with all specimens being within the EU limit for human consumption.

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22

Hakami, Othman. "Synthesis and use of magnetic nanoparticles for the adsorption of mercury from water." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/348890/.

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This study used magnetite (Fe3O4) nanoparticles (NPs), mesoporous silica coated magnetite NPs (SCMNPs) and thiol functionalised silica-coated magnetite nanoparticles (SH-SCMNPs) for Hg(II) removal and recovery from water. The Fe3O4 NPs were prepared via conventional co-precipitation methods. Mesoporous silica coating was created on dense liquid-silica coated magnetite NPs (DLSC-Fe3O4 NPs) using cetyltri-methyl-ammonium chloride (CTAC) as molecular templates and followed by a sol-gel reaction. SCMNPs were functionalised with 3-MPTMS using the co-condensation method. Functionalisation of SCMNPs with this specific organic group was performed to enhance the selectivity of the magnetic NPs towards Hg(II). The characteristics of these particles were assessed at different stages in the production process. The hydrodynamic particle size distribution increased from an average diameter of ~75 nm for Fe3O4 NPs to ~105 nm after silica coating, and was found to be ~111 nm after functionalisation with thiol. The particles were found to be almost spherical with a uniform mesoporous structure with a pore size of ~2.1 nm. The particles were strongly responsive to an external magnetic field making separation from solution possible in less than 1 minute using a permanent magnet. Batch tests were used to evaluate the feasibility of the prepared NPs for the adsorption and desorption of Hg (II) from synthetic wastewater. SH-SCMNPs displayed a high removal efficiency for Hg(II) uptake, with 90% of Hg(II) removed during the first 5 minutes and equilibrium in less than 15 minutes. The adsorption efficiency was highly pH dependant. Adsorption was not affected by the majority of coexisting cations and anions under the conditions tested. 3 M HCl and thiourea in a 3 M HCl solution was an effective eluent for the desorption of adsorbed-Hg on SCMNPs and SH-SCMNPs respectively. This did not result in the destruction of the nanoparticles and they could subsequently be reused, without loss of their activity, in further adsorption tests. The adsorption characteristics of the particles were quantified in a series of isotherm experiments using Hg(II) solution concentrations of between 40 and 1000 μg L−1 at adsorbent concentrations of 4 and 8 mg L-1. The adsorption capacity was higher than for other commonly used adsorbents. Both the Langmuir and Freundlich isotherm models were applied to the isotherm data and the maximum adsorption capacity was achieved when the ratio of adsorbent to adsorbate was low. A semi-continuous method for using the process at a lab scale was developed and was found to be successful in the removal and recovery of Hg(II) and confirmed the results of the batch experiments.

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23

Virjee, Kameel. "Willingness to pay for change : the use of contingent valuation and choice experiments in the Trinidad and Tobago water services sector." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102766.

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Financing water infrastructure has been increasingly identified as a constraint to reaching the Millennium Development Goals for developing countries' water sectors and a significant area in which potential exists to develop sustainable financing is through the design of appropriate tariff policies.
This thesis examines in detail the demand for water service improvements by analysing the willingness to pay for such improvements in Trinidad and Tobago. The basis for the work is a household sample survey conducted in 2003 which assessed the current quality of service and attitudes towards changing the status quo situation. The survey of 1419 households showed that services are poorer than officially stated, and that in response many households have opted for private coping solutions to mitigate the poor service levels of the utility.
Choice experiments, which have only limited previous application in the sector, are employed to develop attribute based utility models describing the welfare effects of service level changes, in addition to the more commonly used contingent valuation method. A rigorous comparison of the two methods is developed. It provides evidence that the choice experiment methodology has benefits for policy analysis around the willingness to pay for service changes in the water sector.
An analysis of proposed marginal cost based tariffs in Trinidad, as a part of wider sector reforms, is used as a case study for the policy applications of the choice experiment based willingness to pay data. Consumers are willing to pay for investments in water infrastructure, provided that they impact upon the actual service received. Marginal cost based tariffs might be socially unacceptable given that whilst significant, the willingness to pay, given likely service changes associated with planned investments by the Trinidadian water utility, for service changes is not sufficient to cover this economically efficient level of tariff.

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24

Jenidi, Youla. "Bioremediation of estrone from water matrices using the enzyme laccase combined with mathematical modelling." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/42868/.

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The presence and impact of steroid estrogens in natural water matrices has driven development and evaluation of wastewater treatment technologies that may reduce the steroid load entering water environments. This work was undertaken to assess and predict the ability of Trametes versicolor laccase to degrade estrone (E1) in water matrices under realistic conditions to wastewater treatment plants (WWTPs) and with consideration of the complex and variable nature of the wastewater matrix. A robust experimental procedure was developed to ensure the efficiency of the enzyme laccase to degrade E1 in water matrices was not overestimated due to errors arising from poor experimental design. These experiments demonstrated that commercially-obtained laccase in concentrations above > 1 mg/ml are inhomogeneous requiring centrifugation prior to use to reduce error and provide more accurate evaluation of laccase capability. Sample filtration, which is necessary for chromatographic analysis, identified regenerated cellulose (RC) membrane filters as the optimum filters for particulates removal from E1 solutions due to their low affinity toward E1 (3.2 ±1.72 %). An optimum enzyme inactivation procedure using hydrochloric acid was also developed to ensure that the enzyme laccase was instantly inactivated without affecting the target steroid E1 itself. Using the established experimental procedure, bench-scale studies evaluating the efficiency of laccase-based treatment in a ‘clean’ water matrix were investigated. Experiments in deionised water provided a proof of concept of laccase ability to degrade E1 in water under realistic ranges of temperature [6˚C - 25˚C] and contact time [0.5 hr – 8 hrs] to the WWTP and evaluate the use of models to fit experimental data and predict within that system. Box Behnken Design (BBD) was applied to determine the number and the conditions of the performed experiments. The experimental data was then utilised to build two different models to predict E1 removal efficiency under any set of conditions and optimise the performance of laccase-based treatment system. The goodness of the fit for each model was tested using statistical indices such as coefficient of determination (R2), mean squared error (MSE) and absolute average deviation (AAD). The artificial neural network (ANN) model showed a better fit to the experimental data than the response surface methodology (RSM) model (RSM and ANN of R2 = 0.9908 and R2 = 0.9992 respectively. In addition, the predictive capabilities of RSM and ANN were tested using a set of statistically designed unseen data that was not previously used in models’ training. Both models showed limited predictive capabilities. The ability of laccase-based treatment to remove E1 in real-world wastewater was studied at bench scale. To account for the complexity and variability of the wastewater matrix, effluent samples during the period December 2014 - June 2015 were characterised for standard water quality parameters, where the temporal variation in wastewater chemical oxygen demand (COD), total suspended solids (TSS) and pH, were observed. A new water quality parameter, “Benchmark” was also developed and applied to quantify the impact of wastewater variability on laccase performance for E1 removal. The average benchmark value in the period between December 2014 and June 2015 was 79.8±3.7%. In addition, the impact of laccase inhibitors, which are likely to be present within the wastewater matrix, such as chloride, copper, iron and zinc, on laccase activity was investigated. The inhibitory effect of chloride ions increased with increasing chloride concentration above 200 mg/l. Copper and zinc ions exhibited negative effects on the enzymatic degradation of E1 at concentrations equal or above 10 mg/l and 200 mg/l. The impact of water matrix temperature, contact time and laccase concentration were studied in wastewater effluent and the experimental data was used to build RSM and ANN models. The predictive capability of the generated RSM model was relatively poor (R2 = 0.863) and even lower than the achieved predictive capability in clean matrix when tested using unseen data, this was partially attributed to the variability of wastewater matrix that could have not been addressed in this type of models. Whilst the improved ANN model showed a better predictive capability than RSM (R2=0.991) An advantage of the ANN model compared to the RSM model and reported for the first time, was the ability to include the impact of matrix complexity and variability on laccase performance, assessed via the benchmark data added as a forth factor in the ANN model. The final ANN model incorporating the matrix variability observed temporally during the sampling period had extremely high predictive capabilities (R2 > 0.99). This model approach holds the potential to help researchers evaluate and optimise laccase-based treatment (as well as other treatment technologies) and predict the removal efficiency of various bioactive chemicals under a wide range of conditions. Performing laccase-based treatment in a continuous reactor, utilising actual wastewater effluent and under realistic conditions to WWTPs, is the next stage that should be investigated in detail.

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25

Wang, Fei. "Experimental and numerical analysis of river lake system and non-traditional water usage in a new Eco-City." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/53211/.

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In recent years, Eco-City, which is designed with consideration for environmental impact and is inhabited by people dedicated to minimisation of required inputs of energy, air pollution and water pollution, has emerged as a way to address sustainability issues by adapting it to their local needs and context. The sustainability of urban water resources, water recycling and more efficient use of water resources will be the key features of the Eco-City. The current study takes Sino-Singapore Tianjin Eco-City as an example to investigate the sustainable use of water resources which focus on non-traditional water usage and ecological water requirements assessment. Firstly, the potential non-traditional water supply was evaluated based on the data acquired from the gauging station and the Eco-City planning data. It was found that rainwater has a great potential for domestic use in the Eco-City from June to September. Differing from other water consumption, ecological demand of the river lake system in the Eco-City was analysed by minimum ecological water requirements determination. An improved wetted perimeter method was used in order to determine the minimum ecological water requirements in the river system. It was found that the current monthly flow rates, with the exception of January to March, are fairly satisfactory. Secondly, an idealised river-lake system was assessed by hydraulics laboratory experimentation and 2D numerical modelling. The experimental and numerical investigations described in this study were undertaken to improve understanding of the hydrdynamic and flushing process within such a river lake system. A water diversion scheme was implemented in order to study lake recharge by river water during dry periods and under augmented flows. Fluorescent tracer experiments and related computer simulations were conducted to assess the performance of different parts of the system before and after implementing the diversion scheme. The results showed that such measures improved flushing, as seen from the perspective of reducing the mean detention time. However, due to poor cross-sectional velocity distribution, recharge alone had little impact on the overall mixing level in the lake waters. The effect of inserting flow deflectors near the lake inlet combined with flow augmentation was then assessed and was found to positively affect the distribution of solutes, by mitigating the occurrence of dead zones. Finally, an eco-hydraulic model was used to determine the levels of fish habitat suitability in the fluvial and lacustrine regions of a new Eco-City. This model has been developed by combining a depth integrated hydrodynamic and water quality model with a Habitat Suitability Index model. Carps were selected as the target species as they represent the major fish population in the study area. Hydrologic data recorded during 2001-2010 were analysed to determine the base flow, average flow and high flow rates, which were used to represent the discharges in the river for the three stages of the carp life cycle: overwintering, spawning and growth, respectively. Numerical model simulations were undertaken to determine the levels of habitat suitability for carps to live at these three life stages. The model results indicated that under the current flow regime the habitat suitability level in the lacustrine region is too low for carps at the growth and overwintering stages. DO depletion, overriding the role of velocity and depth, was attributed to the poorly suited habitat conditions in the lacustrine region. To improve the suitability conditions in the lacustrine region, a DO enhancement scheme was used. Model results showed that the scheme has significantly enhanced the water quality in the lacustrine region. Due to the high flow requirement for carps to spawn in the fluvial region, further numerical model simulations were undertaken to investigate the effect of flow augmentation on the carp spawning habitat suitability.

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26

Hillman, Jesse T. "Prioritizing Rehabilitation of Sanitary Sewers in Pinellas County, FL." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7809.

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Following large rain events, extraneous freshwater contributions known as inflow and infiltration (I/I) bypass the storm sewer and enter the sanitary sewer system. In areas with a high water table, like Pinellas County and the surrounding Tampa Bay area, a majority of the wastewater infrastructure is submerged year round exacerbating the rate of groundwater infiltration. This excess flow overloads the existing wastewater infrastructure leading to sanitary sewer overflows (SSOs). These SSOs result in serious problems for municipalities and utilities across the country. This study was performed in order to assist Pinellas County Utilities in rehabilitating their southern sewer system. To do this, 59 sub-basins across 8 sewer zones were monitored through Pinellas County’s Phase 1 Flow Monitoring Program accounting for over 150 miles of gravity pipe. For each sub-basin, a flow meter was utilized to measure the flow from May to October, 2017. This data was analyzed to separately quantify the amount of infiltration and inflow in each sub-basin, respectively. Once quantified, a Severity Index (SI) was developed in order to give each sub-basin a score from 1-100 as it relates to the condition of the gravity mains in the sub-basin. The SI was a function of locational features available with the use of a Geographic Information System (GIS), such as the distance to water bodies and the soil hydrologic group (SHG), as well as intrinsic pipe properties including the type of pipe material and the age of pipe. Once validated with additional flow monitoring data, the developed SI framework can serve as an additional tool utilized by Pinellas County Utilities to identify areas in need of sanitary sewer rehabilitation. Being that the model only requires easily attainable information, this approach is less time consuming and is inexpensive as compared to traditional flow monitoring efforts. The study also examined the required monetary investment by Pinellas County Utilities in order to abate the 17 sub-basins observed in the study with an infiltration rate greater than the marginal threshold put forth by the Environmental Protection Agency (EPA). The study indicated that gravity pipe rehabilitation does not make a significant impact on groundwater infiltration until at least 30% of the gravity pipes in the sub-basin are lined. This is due to the groundwater table submerging a majority of the wastewater infrastructure. Once this threshold is met, lining was observed to abate groundwater infiltration linearly. The results found that $4.4 million will be required to rehabilitate the affected sub-basins to a marginal rate of infiltration and reduce the flow to South Cross Bayou Water Reclamation Facility (SCBWRF) by an average of 0.72 mgd (million gallons per day). On an annual basis, this reduction in flow will result in approximately $650,000 in treatment costs savings.

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27

Littler, James. "Removal of phosphorus from water using treated acid mine drainage solids and pellets made thereof." Thesis, Cardiff University, 2012. http://orca.cf.ac.uk/22605/.

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This thesis presents work carried out to further the understanding of the use of waste Acid Mine Drainage (AMD) solids to remove phosphorus from wastewaters. AMD can result in serious pollution and so is often treated by the Coal Authority in the UK the resultant solids being a costly disposal issue. Currently the Water Framework Directive (WFD) is putting increased strain on technology used to remove phosphorus at WasteWater Treatment Works (WWTWs). The work presented in this thesis therefore investigates the use of a problematic waste to provide a novel solution to the issue of phosphorus removal at WWTWs. There has been previous work carried out on the use of both AMD solids and AMD-cement pellets to remove phosphorus from wastewaters. This thesis builds upon this work, firstly the phosphorus removal achieved by unpelletised materials studied in this thesis are compared to those studied by others through the comparison of adsorption isotherms. Mirroring other studies, the principal material studied in this thesis was then pelletised using Portland cement as a binder. Phosphorus removal by these pellets in batch tests was determined and optimised. Phosphorus removal was found to increase with a reduction in pellet size and an increase in test length up to the maximum length studied of three weeks. This increase in performance was attributed to the introduction of a calcium phosphate precipitation removal mechanism as a result of the use of cement as a binder for the pellets. This was highlighted through the correlation of phosphorus removal with a drop in calcium concentrations and pH values. It was concluded that the end product of this precipitation was hydroxyapatite. Continuous column tests were performed on the pellets, it was found that the pellets not directly involved in phosphorus removal were still having their reactivity leached out by passing water and so when these pellets became involved in removal, the columns quickly failed.

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Elliott, James N. "An investigation of techniques to identify the causes of foaming in activated sludge waste water." Thesis, Edinburgh Napier University, 2001. http://researchrepository.napier.ac.uk/Output/4874.

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Wastewater activated sludge treatment plants are among the most common forms of biotechnological application. These plants breakdown influents of organic and non-organic matter using a complex bacterial consortia in an aerobic aqueous suspension. One of the most persistent and widespread problems associated with these plants is the formation of thick viscous chocolate coloured scums or foams on the surface of the aeration tanks of the plants. These foams can reach depths of 1.0-1.5 metres and can transfer to the secondary clarifiers and into open water sources. They not only reduce operational efficiency of the plants but they have also been associated with the transfer of pathogens such as Mycobacteria, nocardioform actinomycetes and the opportunistic pathogen Nocardia jarcinica. This investigation had two main aims: 1. To analyse two WWTP with very different characteristics to identify the causative organisms and factors of foaming in them both. 2. To design a sampling strategy for further investigations into foaming In this study the molecular techniques to permeabilise the actinomycetes (the probable foam causing organisms) and hybridise them with specific oligonucleotide probes for use in Fluorescent in situ hybridisations (FISH) were evaluated. In addition four novel 16S rRNA oligonucleotides were designed to detect Nocardia species in environmental samples. FISH using a nested set of probes covering Rhodococcus spp, Gordonia spp, Nocardia spp and the mycolata was evaluated for use in the detection and enumeration of target orgamsms in situ allowing the spatial make up of environmental filamentous flocs to be examined. The operational data from a large pharmaceutical waste water treatment plant was obtained which provided a comprehensive study of the day-to-day workings of the aeration basin over a three-month period, during which a foaming incidence occurred. This data was analysed statistically to find possible indicators of the causes of foaming. Several conclusions were made about the causes of foaming in this plant. An alternative PCR-ELISA methodology was devised to produce semIquantitative enumeration of actinomycetes within environmental samples. A sampling regime was devised for the further study of foaming in activated sludge systems. This regime incorporates the use of FISH; PCR-ELISA to identify and characterise the bacterial consortia within the mixed liquor suspended solids of activated sludge plants, and analysis of the physical characteristics of the plants. A combination of these techniques will eventually allow not only control of foaming but also prevention.

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Diallo, M. A. "Development of an electromagnetic sensor for in pipeline inspection and asset management for the water industry." Thesis, Liverpool John Moores University, 2015. http://researchonline.ljmu.ac.uk/4412/.

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In the UK, the Water Services Regulation Authority (OFWAT), estimates that for all the water and sewage companies there was over 3,365 Ml/d (megalitres per day) of water leakage in the reported period 2010 and 2011, which was still at 3094.21 Ml/day in the 2013 review. Leakage estimates do not include water siphoned illegally through unaccounted connections worsened as asset management of buried utility services has been overlooked for years. With the asset management programme framework (AMP6) due to come into effect in April 2015, water companies are expected to get more out of their existing infrastructure and making considerable investment while keeping bills reasonable for customers. Improving the management of these assets is therefore a priority, as effective asset management enables companies to reduce cost, through leakage management, to plan investments and repairs, and to evaluate operational risks by better fault prediction rather than the current reactive approach. This research focuses on the water distribution network as an asset that include leaks and pipe infrastructure with different materials and diameters. A novel method for leak detection and asset management using an electromagnetic sensor has been developed. Trials in the laboratory showed the sensor is capable of detecting pipe types and conditions thus improving leak detection and asset management in the water industry without extensive digs and modification to existing access valves within the network for system deployment. Furthermore, the sensor would potentially benefit the gas industry by modifying the frequency of operation to match gas filled cylindrical metal structures.

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30

Nabulsi, Y. A. "Control of the irrigation water resources of the Al-Hasa oasis." Thesis, Liverpool John Moores University, 1987. http://researchonline.ljmu.ac.uk/5592/.

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This thesis describes the present situation of the Al-Hasa oasis, which is critically dependent on a single over-used water resource. Evidence is presented to show that water usage is inefficient, and that real improvements are possible, but only if the local farmers are provided with the means of determining the soil moisture levels of their fields. Simple tensiometers and soil moisture cells are considered for this purpose and both would be effective. Soil moisture cells are likely to be the better choice, but more work is needed to evaluate their response to saline soil moisture conditions. The thesis shows that the widely used pressure plate (for laboratory evaluations) is less accurate than is the simpler filter paper system. Such laboratory determinations will be needed to ensure that the chosen field instruments are as accurate as is wanted. An interesting, and still incompletely understood, phenomenon is that the soil grain sizes do affect the accuracy of results from the chosen field instruments. More work is planned on this subject. A crucial factor also affecting the long term security of the oasis is to improve near surface drainage and evidence is presented that details the adverse effects of the present inadequate drainage system. In view of the vast financial investment already made into the drainage of the oasis, improvements that allow a better drainage of each individual field are seen as sensible. Evaluations of more modern soil moisture measuring equipment (transducer and psychrometer systems) reveal that these are inappropriate for use at Al-Hasa. The emphasis of the thesis is on the positive contribution to water use efficiency that can be achieved by the individual farmer. If the thesis conclusions are accepted then the continued prosperity of Al-Hasa can be assured at a very small cost.

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Jafaripour, Amir. "Utilisation of waste gas sludge for waste water treatment." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/4784/.

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This hypothesis driven research investigated the removal of Cu, Fe, Zn and Mn from synthetic metal solutions and real Acid Mine Drainage (AMD) from Wheal Jane mine in West Cornwall UK, employing waste gas sludge (BOS sludge) which is an end waste reside generated from steel production. Batch experiments showed the efficiency and adsorption rates increased with reduction in BOS sludge particle size, lower in initial metal concentration, increase in BOS sludge dosage, an increase in initial pH and increase in agitation speed. Fitting of the Langmuir isotherm model to experimental data gave a good fit with correlation coefficients R$^2$≥0.99 and the selectivity series of BOS sludge was: Cu$^2$$^+$>Fe$^3$$^+$>Zn$^2$$^+$>Mn$^2$$^+$. For single and multiadsorbate systems, a Pseudo second order model was the most appropriate theory to satisfactorily describe experimental data and the rate limiting step for this process was chemisorption. Adsorption was spontaneous and high pH promoted adsorption possibly by precipitation and/or ion exchange processes which had taken place between the exchangeable cations present in BOS and solutions. Results from the treatment of real and synthetic AMD solutions revealed that BOS sludge worked well and hence BOS sludge as a novel low cost material could be used as a sustainable sorbent in AMD treatment technologies.

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Harris, Christopher Nicholas. "Climate change-induced water shortages : improving decision-making in an uncertain future." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5164/.

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An innovative approach to translating probabilistic UKCP09 weather generator information into a usable and replicable risk-based climate change impacts assessment and a basis for robust adaptation planning in the England and Wales water sector is described. Applying metrics of risk in the form of crossing control curves at a reservoir, quantitative assessments of the extent to which a Water Resource Zone (WRZ) can be considered robust to climate change-induced water shortages given the application of adaptations options are made. It is shown in a case study of the North Staffordshire WRZ that in its current set-up, the system cannot be deemed robust to climate change from the 2030s onwards. Applying demand and supply-side adaptation options to the WRZ increases the robustness of the system to varying extents. The approach used shows that it is possible to make decisions on how the WRZ can be made robust to future conditions by identifying key metrics of risk, and applying an acceptable probability of not satisfying that risk in the future. Furthermore, a novel analysis of two sources of uncertainty involved in climate change assessments is produced in terms of water shortage probability for the first time, and two downscaling techniques are assessed.

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33

Shin, Hyun Woo. "A hybrid electronic nose system for monitoring the quality of potable water." Thesis, University of Warwick, 1999. http://wrap.warwick.ac.uk/111031/.

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This PhD thesis reports on the potential application of an electronic nose to analysing the quality of potable water. The enrichment of water by toxic cyanobacteria is fast becoming a severe problem in the quality of water and a common source of environmental odour pollution. Thus, of particular interest is the classification and early warning of toxic cyanobacteria in water. This research reports upon the first attempt to identify electronically cyanobacteria in water. The measurement system comprises a Cellfacts instrument and a Warwick e-nose specially constructed for the testing of the cyanobacteria in water. The Warwick e- nose employed an array of six commercial odour sensors and was set-up to monitor not only the different strains, but also the growth phases, of cyanobacteria. A series of experiments was carried out to analyse the nature of two closely related strains of cyanobacteria, Microcystis aeruginosa PCC 7806 which produces a toxin and PCC 7941 that does not. Several pre-processing techniques were explored in order to remove the noise factor associated with running the electronic nose in ambient air, and the normalised fractional difference method was found to give the best PCA plot. Three supervised neural networks, MLP, LVQ and Fuzzy ARTMAP, were used and compared for the classification of both two strains and four different growth phases of cyanobacteria (lag, growth, stationary and late stationary). The optimal MLP network was found to classify correctly 97.1 % of unknown non-toxic and 100 % of unknown toxic cyanobacteria. The optimal LVQ and Fuzzy ARTMAP algorithms were able to classify 100% of both strains of cyanobacteria. The accuracy of MLP, LVQ and Fuzzy ARTMAP algorithms with 4 different growth phases of toxic cyanobacteria was 92.3 %, 95.1 % and 92.3 %, respectively. A hybrid e-nose system based on 6 MOS, 6 CP, 2 temperature sensors, 1 humidity sensor and 2 flow sensors was finally developed. Using the hybrid system, data were gathered on six different cyanobacteria cultures for the classification of growth phase. The hybrid resistive nose showed high resolving power to discriminate six growth stages as well as three growth phases. Even though time did not permit many series of the continuous monitoring, because of the relatively long life span (30-40 days) of cyanobacteria, improved results indicate the use of a hybrid nose. The HP 4440 chemical sensor was also used for the discrimination of six different cyanobacteria samples and the comparison with the electronic nose. The hybrid resistive nose based on 6 MOS and 6 CP showed a better resolving power to discriminate six growth stages as well as three growth phases than the HP 4440 chemical sensor. Although the mass analyser detects individual volatile chemicals accurately, it proves no indication of whether the volatile is an odour. The results demonstrate that it is possible to apply the e-nose system for monitoring the quality of potable water. It would be expected that the hybrid e-nose could be applicable to a large number of applications in health and safety with a greater flexibility.

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Bannan, Mark. "The effects of powerboat emissions on the water quality of Loch Lomond." Thesis, University of Glasgow, 1999. http://theses.gla.ac.uk/5325/.

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Recently, there has been increased concern about the potential impact of powerboating on freshwater ecosystems. In the case of Loch Lomond, such concern led to the commencement of a programme of boat counting surveys in 1989. In these surveys, it was found that maximum boat numbers are increasing in Loch Lomond. As a logical progression from these surveys, the present study examined the impact of powerboat chemical pollution on the water quality of Loch Lomond. In the first stage of this study, the scale of powerboat pollution was assessed. This was achieved by constructing a simple mathematical model to estimate the total annual discharge of hydrocarbons (HCs) from powerboat emissions into Loch Lomond. By using boat census data and published information about the emission rates of different types of powerboat engines, the total annual input for Loch Lomond was estimated at 25.50 tonnes in 1989 and this input has greatly increased since then. This indicates that there is real potential for hydrocarbon (HC) pollution of Loch Lomond from powerboat operation. Most of the HC material discharged emanated from speedboats powered by outboard motors. To identify and quantify HC pollutant compounds entering water from outboard engines, Gas Chromatography-Mass Spectrometry (GC-MS) analysis was performed on water subject to a controlled pollution discharge from an outboard motor. Altogether, 47 compounds were detected in this exhaust-polluted water (EPW), with most of these being volatile aromatic HCs, such as benzene and alkylated benzenes. Water samples were also taken from three sites in Loch Lomond on two occasions: once in winter, during negligible boat activity and once in summer, at a time of high powerboat activity. No HCs were detected in winter, but some volatile aromatic HC compounds were clearly detectable in summer. These compounds were the same as those most abundant in EPW and found in similar relative proportions. Further experiments in this study involved the analysis of a large number of water samples. To enable this, it was necessary to develop an appropriate new method for the analysis of powerboat exhaust pollutants, which are mostly aromatic HC. All aromatic HCs fluoresce and the new method involved fluorescence spectroscopy analysis, following sample purification by normal-phase column chromatography. This technique is non-destructive allowing subsequent confirmatory analysis by GC-MS. It was found that the new method was fast, precise, highly sensitive and specific to volatile aromatic HCs. The capability of measuring HCs in a large number of samples allowed previously unfeasible experiments investigating: 1) The geographical distribution of powerboat exhaust HCs in Loch Lomond. 2) The depth profile of powerboat exhaust pollutants in the top 1.5 m of the water column. 3) Recovery of water quality, following peak weekend boat activity in summer. It was found that: 1) Volatile aromatic HCs from powerboat exhaust are detectable over much of Loch Lomond on days of heavy powerboat activity, with concentrations of up to 37 ug.l" occurring. 2) Pollutant HCs are found at depths of at least 1.5 m, and are not confined to the surface microlayer (100 urn), The HC distribution with depth was mostly uniform in the field and this was confirmed in controlled experiments in a tank. 3) Recovery of water quality was difficult to demonstrate in the field, possibly as pollution incidents occur continually during summer. 4) HC concentration declined in controlled experiments, in which water was subjected by a controlled pollution discharge from an outboard motor. The time taken for the HC concentration to reach 50 % of the initial HC loading varied but was approximately 7 - 9 days. The toxicity of EPW was investigated by performing 24 hour LC50 (Lethal Concentration for 50 % of test organisms) tests, using the water flea, Daphnia magna (an international standard test organism). The mean LC50 recorded in this study, expressed as the total concentrations ofHC compounds, was 3.72 mg.l". Previous studies suggest that multiplying the Le50 for D. magna by an application factor of 0.001 gives an approximate safe level of a pollutant. Using data collected in this study, a safe level of exhaust He compounds of 3.72 Jlg.r1 would result. In summer, during times of high powerboat activity, such levels are exceeded at many locations in Loch Lomond. The current study has shown that He pollution from a relatively small number of inefficient powered recreational craft using Loch Lomond poses a potential threat to the maintenance of water quality.

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35

Ali, Jafar. "Modelling of thermal plume discharge into shallow and still water." Thesis, University of Huddersfield, 2011. http://eprints.hud.ac.uk/id/eprint/11118/.

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The concerns of global warming are guiding most industries and commercial properties towards addressing their energy usage. In large buildings where air conditioning is required, there is often a need for “chillers” to control the temperature of the building. This process is not environmentally friendly and expensive in terms of energy used and maintenance issues. The alternative is to cool buildings using natural resources such as induced wind drafts and water extraction from rivers and canal. The latter has not been used with optimum effectiveness because the prediction procedures are not sufficiently developed to satisfy environmental legislation. The mathematical approaches are unrealistic and extremely conservative in their analysis and this causes many valid proposals to be rejected. This research is aimed at addressing that situation. It will provide a valid interactive 3-dimensional analysis procedure that will better evaluate the potential of using any British Waterways canal or similar water source for cooling purposes. After water has been used for cooling it is returned to the canal in a heated state as a thermal plume. It is the boundaries of the plume that must be predicted with reasonable accuracy so that environmental legislation is not infringed and livestock is not jeopardised. It is equally important to ensure the analysis is not over sensitive so as to result in rejection of valid proposals. Earlier work studied heat distribution but did not consider the thermal discharge into still and shallow water, as in a British Waterways canal. The studies below investigate several canal sites to evaluate a variety of situations where the discharge plume differs. Criteria including discharge direction, volume of water, temperature differences, speed of discharge and depth of discharge pipe all play a part in the formation of the plume. As such it is possible to develop an understanding of how the thermal plume merges into the still water and how the heat is diffused into the general body of water. In conjunction with site measurements a laboratory experimental scale model tank was built to replicate the real canal site. This allowed data to be varied and measured more readily. Two different types of discharge have been the subject of this research - the first being when the discharge pipe is located at the surface of the receiving water, the second being when it is submerged deeply below the surface. In all cases the temperature and velocity are measured at various points and at a variety of depths to provide a three dimensional plot across the mixing zone. In addition to the mathematical analysis, thermal imaging was used to predict the heat diffusion profiles on the surface of the receiving water in both the canal site and the model tank. CFD software is also used to evaluate the distribution of temperature and velocity within the mixing zone. The mathematical analysis produced an equation to predict the heat diffusion profile in surface discharge. And a number of equations were produced to model the plume path line in submerged discharge- relating to temperature and velocity dilution along and across the path lines. The relative effects of the bed and free surface proximity appeared significantly in the equations. A 3-dimensional model of the size of the plume is presented to demonstrate the results. The procedure followed in this study will enable the Environment Agency personnel to assess the waste heat utilization with greater thoroughness and within a shorter period.

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36

Wang, Zhangyuan. "Investigation of a novel façade-based solar loop heat pipe water heating system." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/12343/.

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Solar thermal is one of the most cost-effective renewable energy technologies, and solar water heating is one of the most popular solar thermal systems. Based on the considerations on the existing barriers of the solar water heating, this research will propose a novel façade-based solar water heating system employing a unique loop heat pipe (LHP) structure with top-level liquid feeder, which will lead to a façade-integrated, low cost, aesthetically appealing and highly efficient solar system and has considerable potential to provide energy savings and reduce carbon emissions to the environment. The research initially involved the conceptual design of the proposed system. The prefabricated external module could convert the solar energy to heat in the form of low-temperature vapour. The vapour will be transported to indoors through the transport line and condensed within the heat exchanger by releasing the heat to the service water. The heated water will then be stored in the tank for use. An analytical model was developed to investigate six limits to the loop heat pipe’s operation, i.e., capillary, entrainment, viscous, boiling, sonic and filled liquid mass. It was found that mesh-screen wick was able to obtain a higher capillary (governing) limit than sintered-powder. Higher fluid temperature, larger pipe diameter and larger exchanger-to-pipes height difference would lead to a higher capillary limit. Adequate system configuration and operating conditions were suggested as: pipe inner diameter of 16 mm, mesh-screen wick, heat transfer fluid temperature of 60oC and height difference of 1.5 m. This research further developed a computer model to investigate the dynamic performance of the system, taking into account heat balances occurring in different parts of the system, e.g., solar absorber, heat pipes loop, heat exchanger, and tank. Data extracted from two previously published papers were used to compare with the established model of the same setups, and an agreement could be achieved under a reasonable error limit. This research further constructed a prototype system and its associated testing rig at the SRB (Sustainable Research Building) Laboratory, University of Nottingham and conducted testing through measurement of various operational parameters, i.e., heat transfer fluid temperature, tank water temperature, solar efficiency and system COP (Coefficient of Performance). Two types of glass covers, i.e., evacuated tubes and single glazing, were applied to the prototype, and each type was tested on two different days of 8 hours from 09:00:00 to 17:00:00. By comparison of the measurement data with the modelling results, reasonable model accuracy could be achieved in predicting the LHP system performance. The water temperature remained a steady growth trend throughout the day with an increase of 13.5oC for the evacuated tube system and 10.0oC for the single glazing system. The average testing efficiencies of the evacuated tube system were 48.8% and 46.7% for the two cases with the testing COPs of 14.0 and 13.4, respectively. For the single glazing system, the average testing efficiencies were 36.0% and 30.9% for the two cases with the COPs of 10.5 and 8.9, respectively. Experimental results also indicated that the evacuated tube based system was the preferred system compared to the single glazing system. This research finally analysed the annual operational performance, economic and environmental impacts of the optimised evacuated tube system under real weather conditions in Beijing, China by running an approved computer model. It was concluded that the novel system had the potential to be highly-efficient, cost-effective and environmentally-friendly through comparison with a conventional flat-plate solar water heating system.

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37

Zubaidi, S. L. F. "Strategic environmental assessment for municipal water demand based on climate change." Thesis, Liverpool John Moores University, 2018. http://researchonline.ljmu.ac.uk/9582/.

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Accurate urban water demand forecasting plays a key role in the planning and design of municipal water supply infrastructure. The reliable prediction of water demand is challenging for water companies, specifically when considering the implications of climate change (Zubaidi et al., 2018). Several studies have documented that weather variables drive water consumption in the short-term, and it enhances the accuracy of the prediction model when it is combined with socio-economic factors. However, the impact of climate change on the municipal water demand has yet to be challenged. To surmount this challenge, more research work is needed to accurately estimate the required quantity of water with increasing water demands. Recently, Artificial Neural Networks (ANNs) have been found to be an innovative approach to predict water demand. This PhD study aims to develop a novel methodology to forecast the impact of climate change on municipal water demands for a long-term time series based on the baseline period 1980-2010. It should be highlighted that, based on our knowledge, this is the first study of substantial duration, based on data collected from 1980-2010, which focuses on the associations between monthly climate change and municipal water consumption. A new approach is therefore proposed to quantifying municipal water demands through the assessment of climatic factors, using a combination of a Singular Spectrum Analysis (SSA) technique, three hybrid computational intelligence algorithms and an ANN model. These hybrid algorithms include a Lightning Search Algorithm (LSA-ANN), a Gravitational Search Algorithm (GSA-ANN) and Particle Swarm Optimisation (PSO-ANN). The SSA technique is adopted to decompose the time series of water consumption and climate variables to detect the stochastic signal for each time series. In the same context, the hybrid algorithms are used to find the best value of learning rate coefficient and the number of neurons in both hidden layers of the ANN model. Based on the performance of each hybrid algorithm, the most accurate and reliable water demand forecast model will be selected and used for estimating future water consumption. The considered environments of this study are applied in Australia and the United States from America for mitigating the uncertainty associated with the geographic location (the data of the United States of America was used to support the reliability of developing the municipal water demands prediction model). Furthermore, the Long Ashton Research Station Weather Generator (LARS-WG) model is utilised to simulate future climate factors over three periods (2011-2030, 2046-2065 and 2080-2099) based on the B1, A1B and A2 emission scenarios and seven General Circulation Models (GCMs). The future projection of these climate factors is applied directly to the impact model of water consumption to obtain the projected municipal water demand for different future periods and different greenhouse emission scenarios. The principal findings of this research are the following: from the model perspective, 1) the SSA is a powerful technique when used to remove the effect of socio-economic factors and noise, and detect the stochastic signal time series for water consumption. 2) The ANN model has better performance in term of optimising the correlation between observed and predicted water consumption when using the (LSA-ANN) algorithm. 3) The evaluation of the ANN model (using a validation data set) for Melbourne and Columbia Cities gives a correlation coeﬃcient of 0.96 and 0.95, and the root mean square errors are 0.025 and 0.016 respectively. These findings indicate the capability of the proposed model to predict water demands with high accuracy in different continents. 4) The high performance of LARS-WG model results are found to be appropriate for the simulation of future climate variables. 5) The harmonisation between future monthly water demand (for the periods 2011-2030, 2046-2065 and 2080-2099) and stochastic signals of climate variables, relative to baseline period 1980-2010, emphasises the reliability of the present methodology. However, from the water demand perspective, the water percentage demand (WPD) are likely to rise in winter, drop in summer and fluctuate in both spring and autumn seasons for all periods and under all greenhouse emission scenarios. The results of WPD distribute between -3.5% and 3% for all periods and emission scenarios. The A2 scenario shows the highest and lowest values of WPDs compared to the A1B and B1 scenarios, in particular, in the 3rd period. The mean of seasonal WPD values shows that there is no dominant scenario as the best or the worst case of water demand over all future periods. The highest amount of seasonal demand happens in winter (A2 scenario, 3rd period), and the lowest amount of seasonal demand occurs in autumn (A1B scenario, 3rd period). In conclusion, this study facilitates the conception of the impact of climate change on municipal water demand from the baseline period 1980-2010.

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38

Paris, Veronique Sara. "Expected impacts of climate change on water and wastewater treatment in the Eastern Ontario region." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27403.

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Climate change impacts the hydrological cycle. The intensity of extreme precipitation events and droughts is expected to increase, creating stress on the water and wastewater infrastructure. The objective of this study is to assess the potential impacts of climate change on the existing water and wastewater treatment infrastructure in rural Eastern Ontario. In total, 13 municipal WTPs and 28 municipal wastewater treatment systems in the Eastern Ontario region were investigated. These facilities were characterized using existing data, questionnaires, and sites visits. On the basis of this information, potential impacts of climate change were identified. One conclusion of this analysis was the potential need to convert lagoon systems to mechanized WWTPs. Such a conversion would represent a significant financial burden for a small community. Therefore, a cost-estimation methodology was developed, based on the existing CAPDET software. Dry periods, heavy rain events, heavy spring runoff and increased temperatures are the critical climate change phenomena that are expected to have the greatest impact on the water infrastructure of the study area. It was found that WTPs on the Ottawa River and the St. Lawrence River are not likely to exhibit water shortages, but those using smaller surface water sources are more vulnerable to water scarcity. Furthermore, this vulnerability to water scarcity will be exacerbated by and increase in water demand resulting from higher temperatures and more severe droughts. Turbidity events typically occur during periods of heavy runoff, and it is expected that climate change will increase the intensity of heavy runoff events. Taste and odor problems due to algal growth during spring and summer are an existing concern for at least five facilities in the study area. It is expected that this phenomenon will increase as a consequence of increased temperatures, increased evaporation rates and longer dry periods during the spring, summer and fall. Inflow and infiltration into the sewer system during spring runoff and rain events are typical problems in the study area, resulting in high peak flows at wastewater treatment facilities. Currently, certain WWTPs in the study area use bypass as a method to cope with extreme peak flows. It is expected that climate change will increase the intensity of spring runoff, and the intensity and frequency of rain events. Consequently, it is likely that there will be an increase in the frequency of bypass events, and an increase in the volume of bypassed wastewater. In lagoon systems, intensified rain events will further swell the normal wastewater flow to several times the dry weather flow, likely causing incomplete treatment of the wastewater particularly at continuous discharge lagoons. During dry periods and warm weather, algal growth in lagoon systems will likely increase. The discharge of effluent containing high quantities of algae will degrade the receiving waters quality. An increased frequency and intensity of periods of low streamflows will reduce the dilution capacity of receiving waters, particularly in small streams. This increased vulnerability may eventually be reflected in more stringent discharge criteria. A reduction in streamflows could also lead to more extensive algal growth, resulting in more turbidity, more taste and odor problems and possibly algal toxins contaminations.

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39

Hashim, K. S. "The innovative use of electrocoagulation-microwave techniques for the removal of pollutants from water." Thesis, Liverpool John Moores University, 2017. http://researchonline.ljmu.ac.uk/7041/.

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Electrocoagulation (EC) is an effective water and wastewater treatment technology; where the coagulants are generated in-situ by electrolytic oxidation of a sacrificial anode. In this technique, pollutant removal is done without adding chemicals; therefore, it remarkably reduces the sludge produced, and consequently reduces the cost of sludge handling. This method has been efficiently used to remove, up to 99%, of a wide range of pollutants such as heavy metals, oil, dyes, and fluoride. However, the EC technology still has a deficiency in the variety of reactor design, and its performance is highly influenced by the chemistry of the water being treated, especially the presence of organic matter (OM), as this inhibits heavy metal removal due to the formation OM-heavy metals complexes. The presence of heavy metals and OM in water resources is one of the most problematic pollutants in Hilla River, Babylon city, Iraq, which inhibits the application of the EC method in that area. Thus, the current study has been devoted to develop a new hybrid EC rector that can be applied to treat water drawn from Hilla River especially, and to treat water containing OM-heavy metals complexes. The aims of this study are therefore; firstly to examine the removal of heavy metals from drinking water in the presence of OM-heavy metal complexes using a new hybrid treatment method that utilises a combination of microwave-electrocoagulation (MW assisted-EC method). Secondly, to present a new configuration for an electrocoagulation reactor (FCER) that employs perforated plate flow columns (which are widely used in the chemical industry) to achieve water mixing, aeration, and temperature control processes. Additionally, the development of statistical models for the EC performance, recovery of hydrogen gas, and the removal of biological pollutants are other targets in the present project. Initially, the performance of the new flow column EC reactor (FCER) was validated in terms of water mixing efficiency, water aeration, and temperature controllability. The results were compared to those of traditional EC reactors. Then, the ability of the FCER to work as an EC unit was validated by treating different pollutants such as fluoride, nitrate, iron, and reactive black 5 (RB-5) dye from drinking water. Then, the ability of the new MW assisted-EC method to remove OM-heavy metal complexes was experimentally proved by treating synthetic water samples contain iron (Fe2+) ions and ethylenediaminetetraacetic acid (EDTA) (C10H16N2O8) (as organic matter). The results obtained showed that FCER achieved a complete water mixing efficiency, and increased the dissolved oxygen (DO) concentration by 110.6% within 10 min, and kept the temperature of water being treated within the range of 22-28 oC for 30 min of electrolysing. While the traditional reactors achieved water-mixing efficiency of 96.5%, increased the DO by 52.2%, and the temperature increased to about 32 oC over the same treatment period. Additionally, FCER was able to reduce fluoride, iron, nitrate, and RB-5 dye concentrations by 98%, 99.6%, 95.2%, 98.6%, respectively. In terms of OM-heavy metal complex removal (the novelty of the present work), the results obtained demonstrated that this novel method removes 92% of this refractory complex within 35 min of treatment at a power of 100 W, temperature of 100 oC, initial pH of 6, ID of 5 mm, and CD of 1.5 mA/cm2. While, the traditional treatment (EC only) removed only 69.6% of this complex under the same operating conditions. It is noteworthy to mention, the new MW assisted-EC method achieved 100% removal of culture-able activated sludge microorganisms ASM from drinking water, which could eliminate the need for costly separated biological treatment units. Statistically, empirical models were developed to reproduce the performance of FCER in terms of fluoride, nitrate, RB-5 dye, iron, and iron-EDTA complex removal. The R2 value for the models of fluoride, nitrate, RB-5 dye, iron, and iron-EDTA complex removal were, respectively, 0.823, 0.848, 0.798, 0.868, and 0.923. Economically, it has been found that the preliminary operating cost of the MW assisted-EC method is 0.628 US $/m3. Additionally, it has been found that the generated hydrogen gas from this new method could be used to reproduce about 2.82 kW/m3 of power, which is a promising amount of power on field scale plants. In conclusion, according to the obtained results, the new MW assisted-EC method is a safe promising alternative to the complicated, expensive, and time consuming traditional treatment methods, as it removes heavy metals in the presence of OM in a relatively short time without the need for chemical additives. Economically, the MW assisted-EC method reduces the need for separated biological treatment unit that require space, money, equipment, and time, because drinking water will be sterilised as it passes through the microwave field. The latter merit makes this new method a cost-effective alternative. Additionally, FCER reduces the need for external mixing and aeration devices that require extra power to work, which makes FCER a cost-effective alternative for traditional lab-scale EC units.

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40

Abdul, Hamid Nor Hazren. "Development of new mathematical modelling for remediation process : case studies on remediation of copper from water matrices using cellulose nanowhisker adsorbents." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/43316/.

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Metal pollutants such as copper released into the aqueous environment have been increasing as a result of anthropogenic activities, a topic causing global concern. Adsorption-based treatment technologies offer opportunities to remediate metal pollutants from municipal and industrial wastewater effluent. The aim of this work was to evaluate the capability of modified cellulose nanowhisker (CNW) adsorbents for the remediation of copper from water matrices under realistic conditions using response surface methodology (RSM) and artificial neural network (ANN) models. The first part of the study explored the preparation and characterisation of modified CNW adsorbents. It also focused on the stability of the modified CNW adsorbents at different time intervals under dry conditions (up to 28 days) and in the water matrix (up to 7 days). The results showed that the modified CNW adsorbents were stable at different time intervals under dry conditions and in the water matrix and proved that the functional groups were permanent and did not degrade under the tested conditions. The stability of these modified CNW adsorbents under these conditions, which is relevant from both the manufacturing and application perspectives, is reported for the first time in this study. The second part of the work focused on using copper as a case study for heavy metal pollution in a clean water matrix, to evaluate removal by modified CNWs under several conditions and ranges appropriate to wastewater treatment plants (WWTPs), using factorial experimental design. RSM and ANN models were employed in order to optimise the system and to create a predictive model to evaluate the Cu(II) removal performance by the modified CNW adsorbents. Moreover, unseen experiments not belonging to the training data set, located both inside and outside the test parameter system, were performed to test the model suitability. This is also novel, as generally only one or two parameter variations have been tested, without checking the chosen model suitability for parameters lying between the tested parameters, and certainly not for parameters lying outside the tested parameter space, as has been done in this study. The results obtained showed that the ANN model outperformed the RSM model when predicting copper removal from a clean water matrix. The Langmuir andFreundlich isotherm models were applied to the equilibrium data, and the results revealed that the Langmuir isotherm (R2 = 0.9998) had better correlation than the Freundlich isotherm (R2 = 0.9461). Experimental data was also tested in terms of kinetics studies using pseudo-first order and pseudo-second order kinetic models. The results showed that the pseudo-second-order model accurately described the kinetics of adsorption. The third part of the work was aimed at gaining a deeper understanding of the complexity and variability of the wastewater matrix, including evaluating the impact of the wastewater matrix temporally on adsorbent performance to remediate copper pollutant from a real-world wastewater matrix. This study has demonstrated that the wastewater matrix composition, which is both complex and variable, has an impact on adsorbent capability and performance. A benchmark study was adopted as a ‘new’ water quality parameter to inform on the effects of the wastewater matrix (wastewater composition and its variability) on the modified CNW adsorbent’s capability to remediate copper from this matrix. Since the process of adsorption from wastewater is often complicated due to the variation in wastewater composition, results obtained from the benchmark experiments were included as one of the independent variables in ANN modelling, unlike in other optimisation studies. The performance of the ANN and RSM models was statistically evaluated in terms of coefficient of determination (R2), absolute average deviation (AAD), and root mean squared error (RMSE) on predicted experimental outcomes. The ANN model including the variability of wastewater composition fitted the experimental data with excellent accuracy and better prediction (R2 = 0.9963) than both the ANN model that did not include this variability (R2 = 0.9945), and the RSM model (R2 = 0.9409). The outcome of this study showed that by supplying the ANN model with the data obtained from the benchmark experiments as the fourth independent variable, it was possible to improve the predictability of the ANN model. Continuous flow experiments for remediation of spiked Cu(II) from the wastewater matrix were conducted. However, the physical structure of modified CNW adsorbents renders them unsuitable for use in column operation. Therefore, a more detailed study of the mechanical properties of CNW adsorbents would be necessary in order to improve the strength and stability of the adsorbents. This work has demonstrated that modified CNW are promising adsorbents to remediate copper from water matrices under realistic conditions including wastewater complexity and variability. The use of models to predict the test parameter system and account for matrix variability when evaluating CNW adsorbents for remediating Cu from a real-world wastewater matrix may also provide the foundation for assessing other treatment technologies in the future.

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41

Bautista, de los Santos Quyen Melina. "Towards a predictive framework for microbial management in drinking water systems." Thesis, University of Glasgow, 2017. http://theses.gla.ac.uk/8261/.

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The application of DNA sequencing-based approaches to drinking water microbial ecology has revealed the presence of an abundant and diverse microbiome; therefore, the possibility of harnessing drinking water (DW) microbial communities is an attractive prospect in order to address some of the current and emerging challenges in the sector. Moreover, these multiple challenges suggest that a shift in the DW sector, from a “reactive and sanctioning” paradigm to a “due diligence/proactive” based approach may be the key in identifying potentially adverse events. My research project has focused on the characterization of the microbial ecology of full-scale DW systems using DNA sequencing-based approaches, with the aim of exploring how the obtained insights could be applied into a predictive/proactive microbial management approach. To achieve this aim, I have focused my efforts on sampling multiple full-scale DW systems in order to elucidate the impacts of: (i) methodological variation and (ii) system properties on DW microbial communities, using a combination of bioinformatics, molecular biology, microbial ecology and multivariate statistical analyses. Regarding methodological variation, I have elucidated the impacts of sample replication, PCR replication, sample volume and sampling flow rate on the structure and membership of DW microbial communities. This was the first time that methodological variation was explored in the DW context, and the first time that multi-level replication has been tested and applied in DW molecular microbial ecology. Moreover, my findings have direct implications for the design of future sampling campaigns. Regarding system properties, I have shown that microbial communities in DW distribution systems (DWDSs) undergo diurnal variation, and therefore are linked to water use patters/hydraulics in the systems. I have also shown that sampling locations in the same distribution system are similar, with OTUs found across sampling locations at different relative abundance and detection frequency levels. An assessment of the impact of source water type and treatment processes showed that disinfection is a key treatment step for community composition and functional potential, and that several genes related to protection against chlorine/oxygen species are overabundant in chlorinated and chloraminated systems. Looking to the future, I believe that the application of a “toolbox” of techniques is key in shifting towards a proactive approach in DW management, that multidisciplinary synergies hold the possibility of changing the way in which DW systems have been studied and managed for over 100 years.

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42

Pattinson, Victoria A. "The transfer, storage and release of water colour in a reservoired catchment." Thesis, University of Huddersfield, 1994. http://eprints.hud.ac.uk/id/eprint/4679/.

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In recent years discoloured water has become a matter of growing concern to water resource managers. Discoloured water is a major source of consumer complaints and is expensive in capital and recurrent costs. The treatment of water discolouration is believed to be associated with a number of health issues, such as Alzheimer's disease. In particular, discoloured water, upon chlorination, is believed to produce carcinogens. The principal aim of this research has been to consider and manage water colour within an entire reservoir catchment system; Thornton Moor Reservoir, the study area, has experienced some of the highest values of colour in the Yorkshire Water Region, and has been an area of significant concern and cost to Yorkshire Water Services. Apparently homogenous subcatchments can produce marked differences in the colour of runoff data. This research has involved an investigation into the relationship between the subcatchment tributary water colour and catchment morphology. The relationships established were used to generate a predictive model for water colour such that areas of high water colour could be identified without intensive sampling. The initial phase of this study considered the transfer network involved in bringing the colour from the catchment to the reservoir. This has involved an analysis of the spatial and temporal variation of water discolouration within the catchment. The consistency of the spatial variation of water colour between the tributaries has been utilised to develop a management protocol which is presently being implemented at Thornton Moor in order to minimise the level of discolouration, whilst maintaining water supplies. Edwards (1987), describes the reservoir as the second line of defence in the protection of water supplies in direct supply reservoirs. No research to date has considered the role of the reservoir in the storage, transmission and release of discoloured water. Empirical evidence at Thornton Moor Reservoir suggests that for the majority of the year, the reservoir operates as a buffer to colour; however at certain times of the year it appears actively to increase the colour entering the treatment works. In considering the entire catchment system, it has been possible to develop a transferable staged approach to catchment management.

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Westgate, Amy. "Evaluation of novel polyethersulfone membranes incorporating charged surface modifying macromolecules for the removal of pharmaceuticals and endocrine disrupting compounds from drinking water." Thesis, University of Ottawa (Canada), 2008. http://hdl.handle.net/10393/27743.

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Recently, there has been an increased concern of the potential effects of pharmaceuticals, personal care products (PPCPs) and endocrine disrupting compounds (EDCs) in drinking water. Their presence in surface waters has resulted in the skewing of sex ratios in aquatic biota and the effect on humans, as yet, remains unknown. Investigation into the effective removal of these compounds by water treatment plants (WTPs) has shown that conventional treatment processes are not very effective in removing these trace compounds. Studies have shown PPCPs and EDCs have been successfully removed by commercial nanofiltration (NF) and reverse osmosis (RO) membranes, but have low flux and high cost. North American WTPs, using membrane separation processes, are typically equipped with microfiltration (MF) or loose ultrafiltration (UF) membranes which, thus far, have proven ineffective for the removal of these target compounds. This thesis focuses on the development of a tight charged UF membrane that effectively removes PPCPs and EDCs from drinking water while still maintaining a high flux and is cost effective. Novel membranes were developed by incorporating charged surface modifying macromolecules (CSMMs) in the manufacturing of polyether sulfone (PES) based membranes. The charged additives were expected to enhance the removal of PPCPs and EDCs by charge repulsion. Controls and three different CSMM (DEG-HBS, DEG-HBC and PPG-HBC) blended membranes were prepared at three different casting conditions and subsequently evaluated for various properties: flux, molecular weight cut-off (MWCO), porosity, charge and contact angle. Experimental membranes were further evaluated for the removal of four representative target compounds, sulfamethazine (SMZ), carbamazepine (Carb), bisphenol A (BPA) and ibuprofen (IB). Removal by a commercial nanofiltration membrane, NF270 (DOW/FilmTec) was compared to the experimental membranes. Removal results from the experimental membranes indicate membranes were unable to sustain effective removal of the target compounds. Typically, removal was initially high but decreased over the run. Membrane characteristics showed membranes had significantly larger pores than the target compounds indicating size exclusion was not the removal mechanism. Charge results indicated CSMM blended membranes were generally unchanged from the control membrane indicating, in addition to the unsustained removal, that charge repulsion was not the removal mechanism. From the shape of the removal curves, it is assumed the removal mechanism is the result of membrane adsorption. The CSMMs were found to have modified the membranes, though not sufficiently, to be considered significantly different than the controls in many respects. Membrane characteristics varied as a result of each CSMM incorporated and depending on each casting condition. Contact angle results for both PES-DEG-HBS and PES-PPG-HBC membranes at all three casting conditions increased in comparison to the controls, presumably because of changes in surface roughness. PES-DEG-HBC, on the other hand, decreased in contact angle at 18%, and increased in contact angle at 20% in comparison to the respective controls. Incorporation of migration time, particularly in the case of DEG-HBC, increased membrane flux without affecting MWCO. Increased PES concentration (from 18 to 20%) saw an increased target compound removal. With the success of the DEG-HBC CSMM, incorporation of migration time at higher PES concentrations appears promising for achieving the desired characteristics. It is recommended that further optimization using CSMM DEG-HBC at increased PES concentrations with migration time be investigated for this application.

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44

Ren, Bo. "Who was in charge of the water conservation? : investigation of water conservation and management in the upper reaches of the Huai, 1912-1949." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/41089/.

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This thesis examines water conservation in the upper valley of the Huai River in Anhui Province, close to the border between north and south China, during the Republic of China (ROC) era (1912-1949). Two main flood relief and water conservation projects are studied in detail. In order to gain a deeper and broader understanding of water conservation policies and practices in China during that period, additional comparative studies were undertaken of two water conservation projects in the lower areas of the Yangtze River in south and northwest China. The main question addressed in the thesis is: What are the key factors affecting the conservation and management of water in China during the ROC era? A further aim of the thesis is to reveal the inter-relationships between water conservation and ROC government policies, and the influence of grass roots actors and international powers in that period. This thesis includes a review of the literature on environmental history, in particular the history of water conservation. For the empirical investigation, a multi-disciplinary, mixed method was adopted, combining the study of historical documents and fieldwork in a series of detailed case studies. Firstly, this study investigates the relief work project in the upper area of the Huai River. The work and the lives of peasant labourers in a water conservation project, including their cooperation and conflicts with upper class engineers and officials are considered in order to provide a vivid and thorough exploration of the worksite. Secondly, the thesis describes and analyses the relationships between various groups (including engineers, the gentry, residents and officials of the Anfengtang Pond community), through a series of stories that highlight their activities, roles and priorities within water conservation and management initiatives. Thirdly, the thesis considers the history of the Lotus Polder and the story of the Jinghui Channel. Fourth, it explores the relationship between international politics and water conservation in the ROC to explain how modern culture and industry penetrated an old water conservation community. The interplay and influence of a wide variety of factors that affected water conservation in the ROC era, such as land policies, economic situation, national finance, wars, traditions and western factors, are addressed and analysed in this thesis.

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45

Ajibulu, Ayodeji Opeoluwa. "Robust adaptive model predictive control for intelligent drinking water distribution systems." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8193/.

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Large-scale complex systems have large numbers of variables, network structure of interconnected subsystems, nonlinearity, spatial distribution with several time scales in its dynamics, uncertainties and constrained. Decomposition of large-scale complex systems into smaller more manageable subsystems allowed for implementing distributed control and coordinations mechanisms. This thesis proposed the use of distributed softly switched robustly feasible model predictive controllers (DSSRFMPC) for the control of large-scale complex systems. Each DSSRFMPC is made up of reconfigurable robustly feasible model predictive controllers (RRFMPC) to adapt to different operational states or fault scenarios of the plant. RRFMPC reconfiguration to adapt to different operational states of the plant is achieved using the soft switching method between the RRFMPC controllers. The RRFMPC is designed by utilizing the off-line safety zones and the robustly feasible invariant sets in the state space which are established off-line using Karush Kuhn Tucker conditions. This is used to achieve robust feasibility and recursive feasibility for the RRFMPC under different operational states of the plant. The feasible adaptive cooperation among DSSRFMPC agents under different operational states are proposed. The proposed methodology is verified by applying it to a simulated benchmark drinking water distribution systems (DWDS) water quality control.

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46

Jones, Alfred Ndahi. "Investigating the potential of Hibiscus seed species as alternative water treatment material to the traditional chemicals." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7181/.

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Developing countries pay a high price for water treatment due to importation of water treatment chemicals. Today, more than 663 million people lack access to a clean water supply which results in many deaths. Hibiscus plant seeds, namely Okra, Sabdariffa and Kenaf were investigated to identify their suitability as alternative water treatment materials to provide clean water supply to people in developing countries. Coagulation and disinfection ability of the extracts were assessed using a jar tester and Collilert-18 Quanti-Tray methods whereas dissolved organic carbon (DOC) test was performed using Shimadzu TOC analyser. The results of this work revealed that all the seed samples possess an anionic coagulant protein with a low molecular weight of 39 kDa. The potential of the seeds in crude form was clearly demonstrated, albeit with some issues regarding organic nutrient addition to the clarified water. However, this challenge was overcome by purifying the seed proteins in an ion exchange column where the impact of DOC addition was significantly reduced in the treated water, as demonstrated via fluorescence excitation-emission matrices. Additionally, the coagulant proteins identified in the region of tryptophan-like fluorescence were found to be stable after heat treatment. Furthermore, sludge production using seed extracts was found to be 5 times lower than that of aluminium sulphate (AS) and the pH of the treated water remained largely unaffected after treatment. Floc strength tests, undertaken using a laser diffraction instrument Mastersizer 2000, showed that the use of seeds as coagulant aids in combination with AS improved floc properties, leading to faster floc growth and shorter coagulation time.

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47

Karabacak, Asli. "Sulphate Removal By Nanofiltration From Water." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612748/index.pdf.

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ABSTRACT SULPHATE REMOVAL BY NANOFILTRATION FROM WATER Karabacak, Asli M.Sc., Department of Environmental Engineering Supervisor: Prof. Dr. Ü
lkü
Yetis Co-advisor: Prof. Dr. Mehmet Kitis December 2010, 152 pages Excess sulphate in drinking water poses a problem due to adverse effects on human health and also due to aesthetic reasons. This study examines the nanofiltration (NF) of sulphate in surface water using a laboratory cross-flow device in total recycle mode. In the study, three NF membranes, namely DK-NF, DL-NF and NF-270, are used. The influence of the main operating conditions (transmembrane pressure, tangential velocity and membrane type) on the steady-state permeates fluxes and the retention of sulphate are evaluated. Kizilirmak River water is used as the raw water sample. During the experimental studies, the performance of NF is assessed in terms of the parameters of UVA254, sulphate, TOC and conductivity of the feed and permeates waters. Results indicated that NF could reduce sulphate levels in the surface water to a level below the guideline values, with a removal efficiency of around 98% with all three membranes. DK-NF and NF-270 membranes showed fouling when the surface water was fed directly to the system without any pre-treatment. MF was found to be an effective pretreatment option for the prevention of the membrane fouling, but no further removal of sulphate was achieved. Parametric study was also conducted. No change in flux values and in the removal of sulphate was observed when the crossflow velocity was lowered. The flux values were decreased as the transmembrane pressure was lowered
however there were not any decrease in the sulphate removal efficiency.

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48

Koebel, Carolyn Michelle. "Analysis of ground vibrations produced by an 80 in3 water gun in the Chicago Sanitary and Ship Canal, Lemont, Illinois." Thesis, Northern Illinois University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1599682.

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Since its completion in 1910, the Chicago Sanitary and Ship Canal (CSSC) has become a pathway for invasive species (and potentially Asian carp) to reach the Great Lakes. Currently, an electric barrier is used to prevent Asian carp migration through the canal, but the need for a secondary method is necessary, especially when the electric barrier undergoes maintenance. The underwater Asian carp “cannon” (water gun) provides such a method. Analysis of the ground movement produced by an 80 in³ water gun in the CSSC was performed in order to establish any potential for damage to the either the canal or structures built along the canal. Ground movement was collected using 3-component geophones on both the land surface and in boreholes. The peak particle velocities (PPVs) were analyzed to determine if damage would be caused to structures located along the canal. Vector sum velocity ground movement along the canal wall was as high as 0.28 in/s (7.11 mm/s), which is much lower than the United States Bureau of Mines (USBM) ground vibration damage threshold of 0.75 in/s (19.1 mm/s), causing no potential for damage to structures along the canal wall. The dominant frequency of ground motion produced by the water gun is primarily above 40 Hz, so the wave energy should attenuate fairly quickly away from the canal wall, with little disturbance to structures further from the wall.

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MOTTA, Breno Guerreiro da. "Determinação do limite de aplicação entre os métodos dinâmico e estacionário em medições de vazão utilizando ADCP." reponame:Repositório Institucional da CPRM, 2016. http://rigeoh.cprm.gov.br/xmlui/handle/doc/15684.

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Johnson, Dana Christine 1968. "The fate of Giardia and Cryptosporidium in marine water." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/290584.

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The fate and occurrence of Giardia and Cryptosporidium were studied in the marine environment to assess their potential for transmission since their transmission to swimmers in fresh waters has been previously documented. The first part of this study was designed to determine the occurrence of Giardia and Cryptosporidium at bathing beaches within the vicinity of an outfall discharging primary treated sewage into Mamala Bay, Hawaii. Sites were monitored monthly and quarterly for parasites by passing 400 liters of marine water through a spun polyproplyene fiber filter. Giardia and Cryptosporidium were detected in primary treated sewage from the Sand Island sewage treatment plant which discharges into Mamala Bay at concentrations of 2,560 cysts and 216 oocysts/liter, respectively. Ala Wai Canal as well as the bathing beaches within the vicinity of the outfall were also found to contain the parasites. The survival of Giardia in marine water was studied in direct sunlight and the dark in marine waters (33- to 35-ppt salinity), canal water (28-ppt salinity) and in phosphate-buffered saline (8-ppt) at 18 to 28°C. Giardia muris was inactivated by 3-logs in the presence of sunlight in marine and canal waters. In comparison, Giardia survive up to 6 hours in PBS under the same conditions. Overall, it appears that salinity and sunlight quickly inactivate Giardia cysts. Thus, Giardia would pose a threat only if the cysts reach the bathing beaches within a few hours. The last phase of this project was designed to develop a more efficient method of collection of cysts and oocysts from water. Methods for the concentration of enteric viruses, Giardia and Cryptosporidium from water requires the use of two different types of filters. This study compared the efficiency of their concentration from tap water and tertiary treated wastewater with a polypropylene fiber cartridge, and the Filterite electronegative and the 1MDS Virosorb electropositive microporous filters. Results indicated that the overall efficiency was greatest for the Filterite filter for both Giardia and Cryptosporidium (p = 0.000762 and p = 0.067069, respectively); and in addition they are easier and faster to process than the polypropylene-wound parasite filter.

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Dissertations / Theses on the topic 'Water and sanitary engineering'

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