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Rydhagen, Birgitta. "Feminist sanitary engineering in rural South Africa : a theoretical framework." Licentiate thesis, Luleå tekniska universitet, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18021.
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This licentiate thesis is a compilation of three papers with an introductory chapter. The papers cover the theory used in the doctoral research project 'Gender and technology. A Comparative study of Water Supply and Sanitation Technologies in India and South Africa'. The introductory chapter describes the motives for the study; a need to connect feminist theory and practical development work within the water and sanitation sector in the Third World. In the introduction, different views on knowledge, and science in relation to other knowledges, are discussed. The first and second paper discuss feminist theory and ecofeminism developed in the Third World or with relevance to Third World contexts. The need to address multiple hierarchies, including gender, class, race and human/nature is evident from this discussion. The third paper describes how participatory methods and the principles behind PRA (participatory rural appraisal) can be used together with feminist theory in research.Godkänd; 1999; 20070320 (ysko)
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Lee, Yuk-yin. "Landscape re-engineering rethinking SENT landfill in sustainable landscape architectural approach /." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38480232.
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Thesis (M. L. A.)--University of Hong Kong, 2007.Title proper from title frame. Includes special report study entitled: Restoration with native species in Hong Kong hillside. Also available in printed format.
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Riccò, Federico. "Design and engineering of 100% polyurethane sandwich structure for sanitary application." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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This work is based on a team research project developed at DUNA-Corradini SpA. The project consists in design and characterization of innovative composite structure, used principally for the production of shower trays for sanitary application.
Starting from a set of existing PUR materials trademark of DUNA-Corradini SpA, DUNAPOL® T products, we worked to combine them to obtain a new composite sandwich structure for 100% PU based shower trays manufacturing, avoiding the use of glass fibres and styrene-based materials in the final product.
The final prototype must be able to satisfy costumer’s requirements in terms of mechanical properties, weight, and production cost.
A brief literature review is presented, regarding polyurethane chemistry, studied materials and sandwich structures. Mechanical tests were performed to study mechanical behaviour and to classify DUNAPOL® T products for sandwich production.
Impact tests were performed on different sandwich structures to identify best materials for both “skin” and “core”, studying the main parameters that affect impact resistance of polyurethanes. Optimization procedure was applied working on PU formulation, core density and skin thickness principally.
Materials for sandwich structures production able to withstand requirements in terms of impact resistance, were identified. Final sandwich structure obtained is characterized by high weight saving (up to 60%), good dimensional stability and low cost related to raw materials used.
Finally, production of shower tray prototypes with different coatings was performed. Production process suitable for 100% PU-based shower trays was defined, exploiting DUNA-Corradini know-how in PU industry. Production process steps are then validated at DUNA-Corradini laboratories, to obtain shower tray prototypes. Then, a FMEA, failure mode and effect analysis, is applied on the production process considered, based on sandwich and shower tray production carried out in laboratory.
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Rydhagen, Birgitta. "Feminist Sanitary Engineering as a Participatory Alternative in South Africa and Sweden." Doctoral thesis, Karlskrona : Blekinge Institute of Technology, 2002. http://www.bth.se/fou/forskinfo.nsf/allfirst2/0ecaa05e81bfec0ec1256fbd0057a98b?OpenDocument.
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Van, Heerden George Adrian. "Evaluation of alternatives for hydraulic analysis of sanitary sewer systems." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86534.
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Thesis (MScEng)--Stellenbosch University, 2014.ENGLISH ABSTRACT: This research project focuses on sanitary sewer systems. When performing an analysis of a sewer drainage system with known constraints, an appropriate model needs to be chosen depending on the objectives of the analysis. Uncertainties are also present in the analysis of sewer drainage systems. The uncertainties and the errors in hydraulic models need to be understood and considered. The required level of accuracy and the type of hydraulic problem that needs to be solved may alter the complexity of the hydraulic model used to solve a drainage system. The wide variety of available simulation models further complicates model selection. With various models available, selecting the most appropriate model for a particular drainage system simulation is important. The various models for sewer drainage system analysis can be categorised in different ways. For example, it is possible to categorise models according to their purpose, which could be evaluation, design or planning. Evaluation models are mainly used to test whether existing systems or planned systems are adequate and require the highest hydraulic detail. Design models are used to determine the size of conduits within a drainage system and require moderate levels of hydraulic detail. Planning models are primarily used for strategic planning and decision making for urban or regional drainage systems and require the least amount of hydraulic detail. An understanding of the available models is required in order to choose the most suitable simulation model for the desired purpose. Some models are derived from the Saint-Venant equations of flow. The most detailed models are typically referred to as fully dynamic wave models and utilise all the components of the Saint-Venant flow equations. By removing terms from the Saint-Venant equations a kinematic wave model can be created. Some less complex models ignore basic principles of hydraulics in order to make assumptions that simplify the process of simulating flows. In this thesis three different models were compared: a detailed model using fully dynamic flow equations, a simplified model using kinematic wave equations and a basic model using contributor hydrograph routing equations. For the drainage system analysis SWMM-EXTRAN was used as the fully dynamic wave model, SWMM-TRANSPORT was used as the kinematic wave model and SEWSAN was used as the contributor hydrograph model. Two drainage systems situated in South Africa were used as case studies and are referred to as Drainage System A and Drainage System B in this thesis. The actual flow rate was recorded at two points with flow loggers, one in each of the two systems. The flow rate was continually recorded at 1 hour intervals for the period 1 July 2010 to 9 July 2010 in Drainage System A as well as in Drainage System B. The same input parameters were used for each model allowing the modelled flow rates to be compared to the measured flow rates. The models provided peak flow results that were within 2% of the measured peak flow rates and the modelled mean flows were within 8.5% of the measured mean flows in most situations. However, when rapidly varied flows occurred the kinematic wave and contributor hydrograph models returned conservative results as they were unable to account for hydraulic effects such as acceleration. The effect of acceleration became most pronounced up and downstream of drop structures and sections where the slope changed considerably. The kinematic wave and contributor hydrograph models were therefore unable to accurately simulate surcharge conditions. The results suggest that the fully dynamic wave model can be used in all scenarios. The kinematic wave model can be used for a design analysis if no hydraulic structures occur in the system. The contributor hydrograph model should not be used for an evaluation analysis, but can be used for a design analysis if a relatively high level of confidence in the parameter set exists and no areas of rapidly varying flow or hydraulic structures exist within the system.
AFRIKAANSE OPSOMMING: Hierdie navorsing projek is gefokus op riool dreineringsisteme. Wanneer ʼn analise van ʼn riool dreineringsisteem met bekende beperkinge onderneem word, moet ʼn geskikte model gekies word afhangende van die doelwitte van die analise. Onbekendes is ook teenwoordig in die analise van riool dreineringsisteme. Dit word belangrik dat die onsekerhede en die foute in hidroliese modelle moet verstaan en oorweeg word. Die verwagte vlak van akkuraatheid en die tipe hidroliese probleem wat opgelos moet word mag die ingewikkeldheid van die hidroliese probleem, wat gebruik word om ʼn rioolsisteem op te los, verander. Die wye verskeidenheid van beskikbare simulasie modelle bemoeilik verder die keuse van ʼn model. Met etlike modelle beskikbaar vir seleksie, is die mees geskikte model vir ʼn spesifieke dreineringsisteem simulasie belangrik. Die verskeie modelle vir riool dreineringsisteem analise kan op verskillende wyses gekategoriseer word. Byvoorbeeld, dit is moontlik om modelle te kategoriseer volgens hulle doel, wat evaluasie, ontwerp en beplanning kan wees. Evaluasiemodelle word hoofsaaklik gebruik om te toets of huidige of beplande sisteme voldoende is en of hulle die hoogs moontlike hidroliese besonderhede benodig. Ontwerpmodelle word gebruik om die grootte van ʼn leipyp binne ʼn rioolsisteem te bepaal en benodig matige vlakke van hidroliese besonderhede. Beplanningsmodelle word hoofsaaklik gebruik vir strategiese beplanning en besluitneming vir stedelike en landelike rioolsisteme en benodig die laagste vlak van hidroliese data. ʼn Begrip van die beskikbare modelle is nodig om ʼn keuse te maak rakende die mees geskikte simulasie model vir die verlangde doelwit. Sommige modelle is afkomstig van die Saint-Venant vergelykings van vloei. Die mees gedetailleerde modelle word tipies na verwys as die volledige dinamiese golf modelle en benut alle komponente van die Saint-Venant vloei vergelykings. Deur die verwydering van terme van die Saint-Venant vergelykings kan ʼn kinematiese golf model daargestel word. Sommige minder gekompliseerde modelle ignoreer die basiese beginsels van hidrologie om aannames te maak wat die proses van golf simulering vereenvoudig. In hierdie tesis is drie verskillende modelle vergelyk; ʼn gedetailleerde model wat volledige dinamiese vloeivergelykings gebruik; ʼn vereenvoudigde model wat kinematiese golfvergelykings gebruik en ʼn basiese model wat bydraende hidroliese versending vergelykings. Vir die dreineringsisteem analise was SWMM-EXTRAN gebruik as die volledige dinamiese golfmodel, SWMM-TRANSPORT was gebruik as die kinetiese golfmodel en SEWSAN was gebruik as die bydraende hidroliese model. Twee dreineringsisteme in Suid-Afrika was gebruik as gevallestudies en word na verwys as Dreineringsisteem A en Dreineringsisteem B. Die werklike vloeikoers was aangeteken by twee punte met vloeimeters, een in elk van die sisteme. Die vloeikoers was deurlopend opgeteken met 1 uur tussenposes vir die periode 1 Julie 2010 tot 9 Julie 2010 in Dreinering Sisteem A sowel as Dreinering Sisteem B. Dieselfde inset parameters was gebruik vir elke model wat dit moontlik gemaak het dat die gemoduleerde vloeikoerse met die gemete vloeikoerse vergelyk kon word. Die modelle het spits vloeiresultate voorsien wat binne 2% van die gemete spits vloeikoerse was en, in die meeste situasies, dat die gemoduleerde gemiddelde vloei binne 8.5% van die gemete gemiddelde vloei was. Wanneer vinnig varierende vloei voorgekom het, die kinetiese golf and bydraende hidrograaf modelle konserwatiewe resultate gelewer het, aangesien hulle nie in staat was om hidroliese effekte soos versnelling te verklaar nie. Die effek van versnelling was op sy duidelikste stroomopwaarts en stroomafwaarts onder valstrukture en by gedeeltes waar die helling aansienlik verander het. Die kinetiese golf en bydraer hidrograaf modelle was gevolglik nie in staat om oorladingsomstandighede akkuraat te simuleer nie. Die resultate wys dat die volledige dinamiese vloeimiddel gebruik kan word in alle omstandighede. Die kinematiese vloeimiddel kan gebruik word vir ʼn ontwerp analise indien geen hidroliese struktuur in die sisteem voorkom nie. Die bydraer hidrograaf model behoort nie gebruik te word vir ʼn evaluerings analise nie, maar kan gebruik word vir ʼn ontwerp analise indien ʼn relatiewe hoë vlak van vertroue in die parameter stel bestaan en geen area van vinnig veranderende vloei of hidroliese strukture binne die sisteem bestaan nie.
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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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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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Tao, Jing. "Treatment of sanitary sewer overflow using fixed media bioreactors." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1228071779.
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Gupta, Anika. "Design of an absorbent and comfortable sanitary napkin for applications in developing countries." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/89967.
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Thesis: S.B., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2014.Cataloged from PDF version of thesis. "June 2014."
Includes bibliographical references (pages 38-39).
Menstrual hygiene is an often-ignored problem in international development: lack of access to sanitation keeps women out of schools and the labor force. Sanitary napkin solutions to this issue normally focus on supply chain and manufacturing. This study aims to look at solutions from a materials perspective, assessing available materials for the properties needed for a good napkin, and reviewing the literature for comparison between these and other materials. Tests for absorption, comfort, durability, and drying time are measured on materials ranging from foam to traditional cottons both individually and in combination. These tests include microscopy observations, retention and wicking rate, tensile resistance, stiffness, and roughness. Though no single design emerges as the most effective for this application, clear differences emerge across materials that narrow down the options for optimal design. This information, in conjunction with user testing, can be used to inform local designs for sanitary napkins across borders.
by Anika Gupta.
S.B.
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Rimpelainen, Satu Julia. "Assessing the cause of irreversible permeate flux decline of reverse osmosis membranes during the treatment of wastewater." Thesis, University of Ottawa (Canada), 1997. http://hdl.handle.net/10393/4064.
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This study was conducted to determine causes of irreversible permeate flux declines observed during the treatment of waste water. The resistance of reverse osmosis membranes to fouling during the processing of waste water at various crossflow velocities is evaluated. Tests were performed with a three weight percent NaCl solution and with batches of a waste stream that is treated at AECL's Chalk River Laboratories. With the NaCl tests, the mass transfer coefficient of NaCl was determined for crossflows ranging from 30 L/min to 60 L/min. Using the mass transfer coefficients calculated with the NaCl tests, the permeate flux was predicted for the waste stream based strictly on osmotic pressure considerations. A three-step cleaning procedure was developed to restore the permeate flux of the fouled reverse osmosis membranes to an acceptable level of 1 L/min. This level is required in order to prevent accumulation within the process. Tests were also conducted to determine if the three-step cleaning procedure had degraded the integrity of the membrane. (Abstract shortened by UMI.)
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Pham, Vu Anh. "Design and implementation of an integrated training and decision support system for the activated sludge process." Thesis, University of Ottawa (Canada), 1998. http://hdl.handle.net/10393/4065.
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In North America, the activated sludge process is commonly used in wastewater treatment. However, there are many aspects of the process that elude researchers, in particular, those that will ensure a successful control and optimization of the process. Because of the biological nature of the activated sludge process, its characteristics are highly dependent on environmental factors and hence can be very difficult to control and manage successfully. A very important factor contributing to an optimized activated sludge plant is the experience of its operators with the activated sludge process. This is achieved through the use of a variety of tools including traditional classroom training, computer based training, expert systems and simulation tools. Some of the tools aim to help the new operators acquire this experience quicker while others aim to enhance the experience of seasoned operators. This project presents a premise that an integration of these tools will be an effective and innovative way to help the operators achieve their goals. Hence, a design of an Integrated Training and Decision Support System (IT-DSS) has been proposed, and parts of the prototype system have been built. Preliminary results showed that such an integrated solution is feasible and realisable although a fully functional system has yet to be realised due to the scope limit. The results of this project provided solid and valuable starting points for the completion of such a step, and they also further support the value of the integration approach that has been put forth.
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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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La, Forge François. "Attenuation of landfill leachate by a natural marshland system." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/6764.
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Since the early 1980's, leachate originating form the Alice and Fraser municipal landfill has been discharging in a natural marshland system located some 300 meters downgradient form the waste disposal site. However, monitoring of the water quality within the marshland indicates that the contaminant level has not yet surpassed background concentration downstream from the main impact area. A mathematical model was developed in an attempt to predict the mobility of several contaminant species within the marshland environment. Parameters needed for the predictive model were gathered based on the physical configuration of the landfill and marshland associated with laboratory derived data on the attenuation capacity of the marshland soil matrix. The behavior, transport and ultimate fate of contaminants in organic soil is greatly affected by their participation in sorption reactions. The adsorption potential of lead, zinc, calcium, sodium and pentachlorophenol (PCP) by marshland soil was evaluated in laboratory through both, batch and column experiments. A multidimensional finite-difference model based on the Advection-Dispersion Equation was used to predict the migration of the above mentioned contaminants. (Abstract shortened by UMI.)
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Duguay, Louise S. "Bench-scale treatability study of a dilute synthetic dairy wastewater, by combined anaerobic-aerobic systems, at ambient temperature conditions." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26369.
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This research project consisted of studying the feasibility of a combined UASB-activated sludge process configuration for treating a dilute synthetic substrate, simulating a dairy wastewater, at a laboratory temperature averaging 23.5 +/- 0.8°C. The bench-scale experimental work was carried-out in two parallel biotreatment systems fed in series. They consisted of relatively small-scale Upflow Anaerobic Sludge Blanket (UASB) reactors of 3.85 and 3.75 L, respectively, followed by 2 L-activated sludge polishing processes. The feed concentration applied to one of the systems consisted of the minimum influent strength recommended for successful anaerobic treatment (∼1 000 mg CODt/L) while the second system was of the domestic sewage-strength range (∼500 mg CODt/L), achieved by dilution.
The mainly soluble complex feedstock used consisted of tap water and Iron Fortified Enfalac(TM) Infant Formula. It was supplemented chemically to ensure that proper (N and P) nutrient requirements were met as well as to increase its buffering capacity and to adjust pH.
Three experimental runs were carried out by applying increasing UASB influent flow rates of 2, 4 and 8 L/d, in both systems. (Abstract shortened by UMI.)
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Zheng, Jian. "Effect of mild microwave pretreatment on characteristics and mesophilic digestion of primary sludge." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27314.
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Wastewater treatment produces a large amount of contaminant-containing sewage sludge, disposal of which is of great concern and is tightly regulated. Anaerobic digestion of sewage sludge is used in most large-scale wastewater treatment plants prior to sludge end use or ultimate disposal mainly due to its advantages of low energy consumption and potential energy recovery. Thermal pretreatment has been studied and successfully applied to improve the quality of the digestion product. Microwave (MW) irradiation has become of interest with some advantages over conventional thermal pretreatment. The objective of this research is to investigate whether MW pretreatment can enhance the anaerobic digestion of primary sludge (PS).
The influence of MW irradiation on the characteristics of pretreated primary sludge was studied in terms of MW intensity, sludge solid concentration, and temperature achieved. The experimental range of sludge of sludge characteristics was sludge solid concentration of 1-4% (w/v) total solids (TS), temperature 35-90°C, and MW intensity of 40 and 80%. MW irradiation was found to increase the concentration of soluble COD (SCOD) in the sludge. The ratio of SCOD/TCOD increased from 2.5% to around 6-7% for 4% TS sludge and MW pretreatment temperature of 90°C. Both sludge solid concentration and MW irradiation temperature were shown to be the most important MW pretreatment parameters in solubulizing primary sludge. MW intensity in the range of temperatures studied had no impact on primary sludge solubilization.
Mesophilic biochemical methane potential (BMP) assays were applied to primary sludge pretreated at MW scenarios of 1-4% TS, temperatures 35-90°C, and MW intensity of 40 and 80%. Again, the BMP assay indicated no obvious difference in samples with the same TS concentration and pretreated to similar temperatures but at different MW intensities. Both higher MW pretreatment temperatures and higher TS concentrations significantly improved biogas production rate and reduced required digestion time to achieve 85% of ultimate digestion. For 4% TS primary sludge samples pretreated to 90°C, biogas production rate increased 37% or resulted in a 28% reduction in digestion time to achieve 85% of the ultimate biogas production. There was some indication that MW pretreatment may have caused some very mild inhibition of the whole (soluble and suspended) sludge sample based on the existence of a 2-3 day lag phase for pretreated sludge samples. While MW pretreatment increased the rate of digestion of primary sludge it resulted in no significant increase in the ultimate biogas production and biodegradation of organic matter in terms of VS and TCOD removal. Analysis of biogas production results from the BMP assays indicated that they could be described by a first order reaction. The reaction rate constant increased with increase of TS concentration and MW pretreatment temperature, but was not affected by MW intensity.
BMP assay of the soluble fraction of pretreated primary sludge was carried out on 4% TS primary sludge pretreated at MW intensity of 80% and temperatures of 65°C and 90°C. The soluble fraction was shown to exhibit no methanogenic inhibitory effects.
In general MW pretreatment at the conditions tested did not result in any significant microbial inhibition and resulted in increased rate of primary sludge digestion without increase of the ultimate degradability of the sludge.
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Hamzawi, Nancy. "Anaerobic co-digestion of municipal solid waste and sewage sludge." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq21990.pdf.
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Ning, Zuojun. "Modeling of simultaneous removal of easily degradable substrates and chlorinated phenols in UASB reactors." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq26137.pdf.
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Savoie, Andrée J. "Eliminating scour and excessive volumes in settling tanks using inclined plates." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ36740.pdf.
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Nguyen, Khanh. "Evaluation of respirometry-based control strategies for the activated sludge process by computer simulation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0002/MQ46599.pdf.
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Hurd, Sarah M. "Low-pressure reverse osmosis membrane treatment of landfill leachate." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0025/MQ52299.pdf.
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Hart, John 1969. "Mass balance model and field calibration for phosphorus removal from municipal wastewaters." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23368.
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Of the wastewater treatment plants (WTPs) in the province of Quebec that are effecting a phosphorus (P) removal program, chemical addition and precipitation is the primary form of P-removal, with biograss growth and/or enhanced biological P-removal (EBPR) providing secondary removals. An overall P-removal of approximately 66% was achieved at these WTPs in 1994.Dessau Inc. of Laval, McGill University and Ecole Polytechnique were contracted by the Ministry of the Environment and Fauna of Quebec to perform an evaluation of chemical P-removal from Quebec municipal wastewaters and the optimization of existing processes. Part of this evaluation and optimization involved clarifying the mechanisms and interactions during chemical P-removal. Many key models from literature were reviewed, but were not entirely adequate.
A static steady-state P-removal model was therefore developed, accounting for the reactions and removals of soluble and particulate forms of orthophosphate and polyphosphate/organic phosphorus. The model traces the path of each P-fraction throughout the chemical removal process, accounting for P-precipitation and adsorption, as well as reductions of TSS and BOD$ sb5.$ Computer programs were constructed for the model, with specific programs written for primary treatment, activated sludge, biofiltration and facultative aerated lagoons.
Samples were gathered at 11 WTPs during June-July 1994; these field data were used to calibrate the computer programs. Computer program output generally agreed with the field data to within 10%. Several of the WTPs sampled obtained a total-P removal of approximately 90% with metal dosed:P molar ratios often below 1.
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Giroux, Emile 1952. "Effect of incinerator ash addition on the efficiency of UV disinfection." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30387.
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The efficiency of UV disinfection of wastewater is limited by particles that shield embedded pathogens. The objective of the experimental work presented herein was to investigate if the addition of microorganism-free, inert, solid, incinerator ashes would create more readily disinfectable particles by concentrating pathogens at the surface of particles. The ensuing reduction of embedded pathogens would increase the efficiency of UV disinfection.Wastewater from the Montreal Urban Community wastewater treatment plant (MUCWTP) was used for the study. The wastewater contained domestic and industrial influents, as well as urban runoff. The physicochemical treatment of the MUCWTP was simulated using a modified jar test. Ash particles (200 mg/L; <75 mum) were added at the same time as either the addition of the coagulant or the coagulant-aid. Furthermore, some tests were done by coating ash particles with a coagulant or coagulant-aid. UV disinfection was carried out on the jar test supernatant at doses of 25, 32, and 40 mW.s.cm-2.
Results showed that the addition of ash particles improved the efficiency of UV disinfection by as much as one log reduction, but the improvement was not statistically significant at the 0.05 level when tested with the one-way ANOVA parametric test and the Friedman non-parametric test.
An analysis of the mechanisms of agglomeration with and without the addition of ash indicated that the efficiency of the UV disinfection process appeared to be enhanced through the production of numerous small flocs, which, however, lowered the overall quality of the physicochemically-treated effluent.
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Choueiri, Najla F. "Fluoride concentrations in the Montreal urban community wastewater : seasonal variations and mass balances." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69788.
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Fluoride concentrations in the Montreal Urban Community's untreated wastewater were analyzed in an attempt to evaluate their levels and seasonal variations. Continual hourly monitoring of the raw sewage, between June 1992 and May 1993. yielded average monthly fluoride concentrations between 0.072 mg/L and 1.984 mg/L, with an annual mean of 0.45 mg/L. Daily variations and frequency distributions showed a wider range of fluoride levels, with the maximum values possibly reaching as high as 4-fold the mean and well over 2 orders of magnitude higher than the minimum values. This suggests that significant massive point discharges occur in the sewer network. Daily monitoring of the precipitation showed that the mean fluoride concentration in liquid precipitation generally fluctuates between 0.030 mg/L and 0.741 mg/L, whereas the average fluoride specific mass in dry precipitation ranges between 0.096 kg/km$ sp2$ and 2.775 kg/km$ sp2$. Seasonal trends have been depicted for fluoride levels in both the raw wastewater and the precipitation. Groundwater sampling yielded an average fluoride concentration of 0.13 mg/L, and analysis of the melting salts used by the City revealed that these do not contain any fluoride. Data from the City's water treatment plants showed that the average fluoride concentration in their raw water is 0.20 mg/L. This is in contrast to the value of 0.13 mg/L used in the literature. Mass balance analyses have shown that the mass of fluoride resulting from infiltration and non-fluoridated waters, as well as that due to the domestic habits of the population constitute, among the identified sources, the major input of fluoride mass into the wastewater. Nevertheless, unidentified sources of fluoride, consisting essentially of industrial discharges, still account for the largest portion (${ approx50 %}$ of the total) and contribute, as an annual average, 375 kg/day.
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Tremblay, Catherine V. M. "Biological and physico-chemical removal of iron from potable waters : redox potential as an indicator of treatment effectiveness." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20523.
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The first objective of this research was to evaluate oxidation-reduction potential (ORP) as an indicator of effective iron removal in a biological process and to determine its relationship to dissolved oxygen (DO) and residual iron in the filtered water. Biological removal of iron to produce drinking water was established on one full-scale and two pilot-scale plants at two sites in France. Results show that below a minimum DO concentration of approximately 0.3 mg/L, residual iron concentration was related to ORP in the filtered water. Above the minimum DO requirement, ORP on the order of approximately 500 mV consistently reflected effective iron treatment and residual iron concentrations less than the French norm for potable water of 0.2 mg/L.Secondly, two catalytic materials of filtration known as Ferrolite MC2 and Purolite were investigated on pilot-scale for their capacity to oxidize iron and manganese. Results showed that both materials eliminated dissolved iron to below detection levels regardless of DO or filtration rates up to 15 m/h (Ferrolite MC2) and 20 m/h (Purolite). During the trial period where no filter regeneration was carried out, the elimination of dissolved iron and dissolved manganese, respectively, were 100% and 77% for Purolite and 100% and 65% for Ferrolite MC2 for a raw water with 3.47 mg/L of dissolved iron and 0.317 of dissolved manganese. Purolite filtered a total volume of 1127 L or 137 L/kg of catalytic material and Ferrolite MC2 filtered a total of 1457 L or 217 L/kg.
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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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Younes, Serge. "Improved quality control procedures and models for solar radiation using a world-wide database." Thesis, Edinburgh Napier University, 2006. http://researchrepository.napier.ac.uk/Output/4282.
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This thesis deals with- various aspects of broadband horizontal solar irradiance. Quality control of measured datasets are identified and analysed. It was found that solar irradiance datasets may contain significant errors. These sources of errors were divided in two categories, the inherent instrument errors and operation related errors. Methods of assessing the quality of the datasets were evaluated and found to be unsatisfactory. A new method was hence developed to quality control the solar irradiance data. The quality control procedure consists of two tiers of tests. The first tests are physical tests that identify and remove data points that are physical impossibilities. The second tier tests consist of the creation of a mathematical envelope of acceptance in a sky clarity index domain. This envelope of acceptance is based on multiples of standard deviations of the weighted mean of clearness index to diffuse ratio. The available datasets in this study were thus quality controlled to remove any obvious outliers. Modelling the solar resource is an important tool for engineers and scientists. Such models have been developed since the second half of the 20th century. Some models rely on one or two meteorological parameters to estimate the solar irradiance, while other models are more complex and require a far greater number of points. Two of these models have been analysed and evaluated. The two models are all-sky, broadband solar irradiance models. The first model analysed is the Meteorological Radiation Model, or MRM. This model is in fact a sunshine based model, with atmospheric turbidity taken into account as well. The beam irradiance component was found to be acceptable given the number of inputs required by the model. Any extra parameters would increase the complexity of the model, without noticeable improvements. The regressions were modified to take into account sunshine fraction banding. However the diffuse irradiance was identified as one which had the potential III for improvement. Thus, in the present work an attempt has been made to develop improved models. The new model was found to be far superior to the older, original model, thus the name Improved Meteorological Radiation Model, IMRM. The second type of model investigated is the cloud based radiation model. This type of model is simple to use and rely on regressions between irradiation, solar altitude angle and the cloud cover. Careful analysis of the cloud distribution reveals certain flaws in the current regressions. New regressions were formulated and the result was a model superior to all its predecessors. Clear-sky modelling is important for maximum load calculations; however, there is no method of extracting with accuracy clear-sky broadband data. Clear-sky identification techniques were evaluated and a new method was devised. These new datasets were used on four clear-sky models, MRM, Page's Radiation Model, PRM, Yang's radiation model and Gueymard's REST2 model. It was found that using this new method of extracting extremeclear- sky data, the models performed better than when using quasi-clear-sky data. Solar radiation modelling is not an end by-itself, it must serve a purpose for engineers in their applications. Napier University has installed a 160m2 photovoltaic facility in 2003. A 27 -year solar radiation dataset was available for Edinburgh, to do feasibility calculations for the project; however this dataset contained gaps in the data. The cloud radiation model developed in this study was utilised to this end. In addition a complete life cycle analysis was performed on the project, and it was found that with an average efficiency at around 12%, the facility will payback its embodied energy in eight years, and based on a relatively conservative forecast of energy prices, the financial payback is set at under 100 years.
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Shahriari, Zavareh Haleh. "Evaluation and modeling of a membrane activated sludge system." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26395.
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A membrane activated sludge bench-scale system was used to treat a complex synthetic wastewater over a wide range of operating conditions ranging 1 to 15 day(s) solids retention time (SRT) and 4 to 12 hours hydraulic retention time (HRT). Although the membrane reactor was able to provide good to excellent separation of particulates from the liquid in the mixed liquor over these operating conditions, the membrane failed, primarily due to clogging at operating conditions outside of these ranges. Various techniques, such as coagulant addition, were attempted to further expand the operating range but they failed. All runs were conducted until steady state conditions existed at which time data for modelling were collected. Performance of the system primarily for carbon and nitrogen removal is described for conditions where solids loss or clogging was nonproblematic. Different mathematical models to predict the behaviour of an activated sludge system and to estimate stoichiometric and kinetics parameters are presented. (Abstract shortened by UMI.)
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Gabr, Tarek Zeiad. "Hydraulic overload of upflow anaerobic sludge bed reactor treating landfill leachate." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26482.
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The impact of hydraulic shockloads on UASB reactors operating at mesophilic conditions (T = 35°C) was studied. The wastewater, landfill leachate, was pretreated by filtering it through peat moss. The reactor was 1/2 filled with sludge previously acclimated from a pulp mill wastewater treatment facility.
The shockloads imposed on the reactor were hydraulic where the flowrate of the influent wastewater was increased by 2--3 times the initial flow rate at quasi steady-state (corresponding to a change of HRT from 2.5--3 to 1--1.5 d) where the influent concentration was maintained around 10 g COD/L. Two modes of shock-loading were compared: continuous versus intermittent for a total duration of 3 hours, where the intermittent operation distributed the flowrate increase over 9 hours to make a total of 3 hours.
The results showed that a UASB reactor can endure a single shockload of OLR close to 9.6 +/- 1.8 g COD/L.d and recover to pre-shock conditions in a period not exceeding 30 hours. Intermittent shock feeding resulted in better effluent quality; nonetheless, it took a longer time to recover, and was more prone to solids washout. (Abstract shortened by UMI.)
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Seaman, Laura. "Advanced aerobic digestion to optimize pathogen reduction: Staged pre-treatment in aerobic digestion." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27293.
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Land application of biosolids is a desirable solution for smaller communities that utilize aerobic digestion. However, traditional aerobic digestion produces Class B biosolids at best which raises public concern regarding the fate of pathogens following land application. The main goal of this work was to determine a plan to help an aerobic digestion WWTP achieve improved pathogen destruction. An approach of studying the effect of a pre-treatment step prior to digestion was developed following site visits to eight aerobic digestion facilities in Ontario. The experimental phases of this work evaluated the effect of aeration rate, temperature and retention time on pathogen reduction in 12 setups. The four best conditions were carried out with digestion to evaluate the ultimate impact of pre-treatment on digestion. The results indicated that a micro-aerobic, highly reducing environment produces adverse conditions within the pre-treatment column which also impact subsequent digestion and resulted in decreased pathogens.
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Sherif, Ranya. "Microaerobic pretreatment of extended air sewage sludge for the enhanced destruction of pathogenic bacteria in aerobic digestion." Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27919.
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The inactivation of pathogens in sewage sludge reduces the risks of infection through contaminant pathways associated with handling and disposal. Domestic sludge sourced from a rural treatment plant was found to contain high levels of the indicator microoganisms E. coli and fecal coliforms and pathogenic bacteria Salmonella spp., Shigella spp., and C. perfringens. An effective and simple approach to enhance pathogen removal in a rural treatment setting was desired. Existing literature suggested that draw/fill staged configurations tended to yield better inactivation rates. Other literature suggested that the build-up of inhibitory compounds such as VFAs were detrimental to pathogens and that VFAs could be accumulated in higher temperature microaerobic conditions. The investigation of microaerobic pretreatment was trialed as a novel approach to staged digestion for improved pathogen removal. Microaerobic pretreatment of aerobically digested sludge improved inactivation of aerobic bacteria but the inactivation of persistent spores of C. perfringens were inconclusive.
Microaerobic pretreatment alone was investigated in three phases of the experiments and did not result in inactivation greater than one log reduction for any bacteria monitored. In Phase I where feed solids concentration was varied across four reactors, the lowest solids loading of 1.1% TS showed the best removal rates of pathogens. In Phase II, contact time was evaluated in terms of feeding frequency and residence time. It was found that less frequent feeding and longer residence times were more effective in removing pathogens as expected from the reactor kinetics and suggested by the literature. The impact after digestion was found to be significant in Phase III for fecal coliforms, E. coli, Salmonella spp. and Shigella spp. It appeared that changes to the sludge matrix in microaerobic pretreatment improved digester performance in terms of pathogen removal.
Operating variables were monitored to gain an understanding of the factors impacting performance. Statistical analyses were performed at the 90% confidence interval to determine which if any factors differed significantly between systems and stages. The major findings were that mesophilic pretreatment (35°C) with air supplied at 0.06vvm yielded significantly higher ammonia levels after pretreatment than did pretreatment at ambient temperatures. This was hypothesized to account for the significantly greater extent of nitrification observed in downstream aerobic digestion over the effluents from digestion without pretreatment and those that were pretreated under ambient microaerobic conditions. Accordingly, the pH in those digesters was significantly lower than after digestion without pretreatment and after digestion with ambient microaerobic pretreatment. This enhanced depression in pH was hypothesized to account for the significantly enhanced inactivation in pathogens.
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Zhang, Qiuzi. "Kinetic formulations for growth and substrate uptake in biological wastewater treatment." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28361.
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The Monod or hyperbolic kinetic formulation became the de facto kinetic descriptor in activated sludge models in the '80s-'90s. It still plays a prominent role in activated sludge models; however, a dual hyperbolic formulation (with respect to both substrate and active biomass) that implicitly accommodates storage as well as more rationally describes metabolic kinetics is more prominent in governing metabolic functions in activated sludge models (ASMs) promulgated by working groups under the aegis of the International Water Association (IWA). There are other kinetic formulations used in the models of this group as well as models of the activated sludge process formulated by others. There is lack of consistency in the choice of kinetic formulations for various processes even within the IWA family of models.
This thesis examined the basis for the common Monod and dual-hyperbolic formulations and puts forward theoretical justifications of them based on various considerations of mass transfer, storage and metabolic rate formulation. Other models were developed based on major governing principles.
Models used in biological wastewater treatment are Eulerian gross descriptors of a process involving mass transfer, many substrates, and metabolic pathways and their enzymes, contained within many microorganisms. Any model at this level is merely a fit of mathematical formulations to data. As number of processes in biotreatment models increases along with mathematical descriptors and their associated coefficients, fitting an overall model improves to a point. But beyond this there has been little justification of the Monod or other kinetic expressions. Since a variety of formulations have been proposed for two of the primary metabolic processes which are hydrolysis of complex substrates and then metabolism of resulting readily degradable (or simple) substrates, the primary objective of this study was to examine these processes by experiment and determine the most appropriate models for each step.
A chemostat was used in this study to culture active biomass acclimatized to a feed containing starch, a complex substrate requiring hydrolysis, and glucose which is readily biodegradable and also a product of starch hydrolysis.
Active mass samples were taken from the chemostat and placed in batch reactors where varying concentrations of active mass were exposed to varying concentrations of either glucose or starch. Before adding any substrate to the batch reactors the active mass was aerated for a period of time until DO change was not observed to ensure that any stored or extraneous substrate was metabolized. After addition of one or the other substrate, the rate of dissolved oxygen (DO) uptake was monitored over the initial 15 minutes in the batch culture. Rapidly changing conditions dictated the necessity of using DO as a surrogate for either starch or glucose. Over 249 models were examined for their ability to describe glucose metabolism for 16 different batch experiments. The Monod model gave a good fit to the data. Other models that were equally applicable were too complex or made no scientific sense.
Another series of batch tests were conducted using only starch as a substrate. Again substrate concentration and active mass concentration were varied in the batch tests in six different batch runs. The results from these experiments were again used to determine the adequacy of 249 starch hydrolysis models. The Monod type relationship and a dual hyperbolic relation again proved to be the most reasonable choices. Also a first-order model based on starch concentration was applicable. However no general set of coefficients that applied to all experiments was found for any model; it is necessary to calibrate either model to environmental conditions. All of these models are fairly simple in terms of concept as well as determination of parameters and have scientific sensibility in describing hydrolysis of SBCOD.
Keywords: wastewater, activated sludge, dissolved oxygen, modeling
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Bordeleau, Etienne Louis. "Analysis of sludge pretreatments for conventional anaerobic digestion wastewater treatment plants." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28631.
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Pretreatment of primary sludge, waste activated sludge, and comingled sludges has become of substantial interest for the improvement of the rate limiting hydrolysis step during anaerobic digestion. As primary sludges are already easily degraded, waste activated sludges provide the most noticeable improvements in anaerobic digestion (AD) as a result of sludge pretreatment (SPT). A vast literature and theory review was conducted to establish high-potential treatment and result ranges. The average wastewater compositions for total chemical oxygen demand (COD) and total solids (TS) were 16-43 and 13-40 g/L, respectively. Sludge pretreatment percent solids solubilisation ranges for all common SPT technologies were 13-42% for both particulate COD and total suspended solids (TSS). Subsequent anaerobic digestion enhancement ranges were percent reductions in total COD and TS of 24-55 and 22-46%, respectively, as well as biogas production increases of 9-43%. The ranges shown here were fairly representative of those observed for all SPTs. Additional SPT technology information for full-scale design was also gathered.
A MS Excel spreadsheet wastewater treatment plant model (referred to herein as PretrAD) capable of comparing control and SPT incorporation scenarios was created. The PretrAD output was verified against a third party commercial model. PretrAD allows the user to input data on performance of all unit processes found in a typical biotreatment wastewater treatment plant (WWTP). Various return flow paths and other attributes of a WWTP can be specified and provide versatility and comprehensiveness. A database of typical performance data for all unit processes was compiled and used in PretrAD and for comparing performance of WWTPs with and without SPT.
The stirred ball mill, high pressure homogenizer, and ultrasound technologies were mechanical processes with sufficient comparable data for inclusion in PretrAD. Conventional heating and microwave heating technologies were included as thermal processes. Alkaline and ozone technologies were included as chemical processes. Finally, the common conventional heating + alkaline (thermochemical) technology was also included alongside a purely financial assessment of a proposed microwave heating + alkaline technology incorporation scenarios.
PretrAD was then used to evaluate treatment benefits by varying a number of performance parameters with and without SPT. Operating parameters that were changed were normal and low heat recoveries at the anaerobic digester, normal and doubled sludge disposal distances, low-peak influent flow regimes, and low to high SPT energy demands (evaluated with identical solubilisation results). Control and SPT scenarios were performed for all variables and both mesophilic and thermophilic AD.
Overall net WWTP treatment costs based on energy inputs and recoveries along with chemical inputs were compared for the various scenarios. It was found that an all average influent flow regime represented (within 5%) all annual flow regime combinations of low, average, and high flows and their associated quality variations. Following the basic comparisons of control and SPT scenarios, additional runs were conducted with increases of 25 and 50% for the energy demands of each SPT.
Mesophilic AD scenarios always had lower final costs than thermophilic AD scenarios under identical treatment parameters. Practical (cost-effective) and impractical (higher than control costs) scenarios were found for all SPTs except thermal and thermochemical processes. Thermal and thermochemical processes were always practic31 and always impractical, respectively, when compared to control scenarios using identical conditions. When different scenario conditions were compared, both thermal SPTs were deemed impractical when high cost results were compared to low cost results.
Solids loadings and heat recoveries were the most cost-influential variables of PretrAD. Other important qualitative results were not incorporated into the evaluation. They include but are not limited to dewatering improvements, pathogen reduction, anaerobic digester vessel size reduction, and hydraulic residence time reductions for the anaerobic digester. Inclusion of these parameters could render some SPTs practical for scenarios where they were deemed impractical on a pure cost of treatment basis. Furthermore, full-scale incorporation drawbacks such as additional unit costs, operation and maintenance demands, and actual throughput capacities could render some practical scenarios impractical.
The constructed PretrAD model has been proven effective for the rapid determination of treatment plant costs related to SPT incorporation. A tool such as this is vital for the site-specific analysis of SPT technologies.
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Mosqueda-Jimenez, Daniella Berenisse. "Impact of manufacturing conditions of polyethersulfone membranes on final characteristics and fouling reduction." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/29034.
Full textAbstract:
The use of membrane processes in drinking water treatment has increased exponentially in the last few years. However, one of the shortcomings that hinders their wider application is the propensity of membranes to become fouled, causing the permeate flux to decrease with time. One of the main membrane foulants is the natural organic matter (NOM) present in water sources. Membrane characteristics and performance are affected by membrane preparation conditions. The objective of this thesis was to investigate the impact of hydrophobic surface modifying macromolecule (SMM) addition and other manufacturing conditions on the membrane characteristics and performance of polyethersulfone (PES) membranes. As it was necessary to test numerous membrane coupons prepared under many different conditions, during the first stage of this study a membrane test protocol was established. Small test cells gave very similar results to those produced by a larger test cell, which is recommended by USEPA for membrane testing. The test protocol was relatively short in duration and required a small amount of test solution. Moreover, as membrane compaction rate depends on the material, it was important to incorporate a precompaction step into the test protocol in order to quantify the contribution of membrane compaction when fouling was studied.
The second stage of the study evaluated the impact of different membrane preparation conditions (i.e., solvent evaporation time and PES concentration) and the impact of three different SMM formulations. The three SMMs differed only in the polyol used in their synthesis. SMM41, the most miscible SMM, proved to be the most promising SMM. In general, the increase of PES concentration and/or evaporation time, together with the surface modification, produced tighter membranes with improved TOC removals, decreased NOM deposition on top of the membranes and decreased flux reduction, but also resulted in a reduced permeation rate. The best SMM41-modified membranes performed as well as their unmodified counterparts in terms of pure water permeation rate, TOC removal, and final flux. SMM41 modification significantly reduced the amount of NOM deposited on the membrane surface, and in general reduced the percentage of flux reduction. Thus, the effect of surface modification on the membrane performance was positive but marginal.
Membranes prepared with PVP had higher porosities and consequently, larger permeation rates than the membranes prepared without PVP, and similar TOC removals. In this case the effect of the SMM41-modification was statistically insignificant.
When different fractions of NOM were used as feed solutions a significant effect was observed for all the response variables. Low-molecular-weight NOM, as that present in most groundwaters and coagulated surface waters, caused less fouling, having a higher permeate flux at the end of the experiment; however, smaller TOC removals were observed. In general, there is a compromise between the TOC removal that the membrane can achieve and the permeation rate. Higher TOC removal is achieved by membranes with smaller permeation rate.
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Tauvette, Geoffrey Yvon. "Operating strategies for a nitrogen deficient waste using a continuously fed cyclically aerated sequencing batch reactor." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0022/MQ50666.pdf.
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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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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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Villarreal, Rodriguez Marco Antonio. "Assessment of nonlinear least-squares estimation of monod kinetic parameters from batch reactor experiments." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59832.
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It is known that the use of batch experiments for the estimation of kinetic coefficients is a better alternative than continuous flow reactors, in terms of the time needed to perform the experiments.In this study a new methodology to estimate the four Monod-kinetic parameters from batch reactor data set is presented. This method fits biomass and substrate plots simultaneously via nonlinear least-squares analysis. The nonlinear equations are solved via the secant method.
The methodology performed satisfactorily with two synthetic data sets. It was also applied to seven batch reactor data sets available in the literature and to ten data sets from batch experiments using wastewater and sludge from the municipality wastewater treatment plant in Granby, Quebec. The constants estimated vary considerable among themselves, and some were not within the range of values commonly found in the literature. The methodology proposed yields parameter estimates which produce the minimum sum of squares residuals.
It is believed that further studies are needed if one is to attempt estimating the four Monod-kinetics constants using batch reactors experiments.
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Peng, Ji 1974. "Characterization of permanent fouling on the surfaces of UV lamps used for disinfection." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79254.
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This research investigated the origins and formations of permanent fouling. Four instrumental analyses were employed. They were Sleeve UV Transmittance (SUVT), Atomic Force Microscope (AFM), X-Ray Fluorescence (XRF), and Scanning Electron Microscope (SEM) combined with Energy Dispersive X-ray Microanalysis (EDX).It was verified that permanent foulants were trapped initially by the inherent holes and peaks on sleeve surfaces. After long term periodical chemical/mechanical cleaning, the wipers of cleaning systems would damage sleeve surfaces severely, causing scratches or holes with wide surface areas, which may be termed mechanical deterioration of the sleeves. Thus, foulants would be trapped more easily by these scratches, and would be attached tightly to the surfaces of these scratches or to each other. Using instrumental analyses, the compositions of permanent foulants were found to be site specific. In general, iron, aluminum, calcium, magnesium and phosphorus composed the majority of the components of the permanent foulants.
This research attempted to correlate permanent fouling to the site-specific wastewater quality. However, although it seemed that wastewater quality could affect permanent fouling to some extent, there was no robust relationship between them. Thus, wastewater quality parameters cannot be used at this stage to predict the future influence of that wastewater on permanent fouling.
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Cailas, Michael D. "Development, analysis and comparison of models for respirometric biodegradation data." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74648.
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When continuous monitoring devices such as the electrolytic respirometer are used for performing biodegradation experiments, cumulative data are acquired. The structure of these observations limits the reliable application of existing methodologies for analyzing cumulative respirometric biodegradation trends, because the resulting error terms are likely to be highly autocorrelated. To overcome these limitations it is proposed that the Oxygen Uptake Rate (OUR) should be used as the data source for further analysis, because the dependence of the error terms is then removed. To model uniform reaction rate respirometric biodegradation OUR data trends, 1st and 2nd-order OUR models are proposed. Theoretical and practical assessment of these models in comparison with their cumulative counterparts indicates that (a) they are likely to have improved nonlinear behaviour, (b) their parameters will have more reliable confidence interval estimates, and (c) the optimal duration of an experiment performed to estimate the OUR model parameters is shorter compared to that required for estimating similar parameters in the case of cumulative biodegradation data. During respirometric biodegradation studies, data trends with distinct microbial growth periods often appear as well. In order to describe such observations a new diphasic OUR model is proposed, which provides valuable information for each phase in the form of 1st-order reaction rate coefficients and the duration of the first phase. Application of this model to a number of data cases indicates that this model can be regarded as a practical alternative for modelling diphasic respirometric data trends. A similar conclusion was drawn for a proposed two-stage respirometric biodegradation model. In the present study an approach is also suggested for performing statistical comparisons between biodegradation curves which have been obtained under different experimental conditions. This approach is based on the proposed OUR models, t
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Gopalakrishnan, Sridhar. "Electroosmotic and combined field dewatering of sludges." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23367.
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Four type of suspensions were dewatered by electroosmosis alone or by electroosmosis combined with other methods: (1) Clay (Bentonite or hydrocol)--electroosmosis with constant voltage continuous DC or square wave interrupted power. In the interrupted mode, a constant voltage was applied for t$ sb1$ seconds (the on-time) followed by a short circuit for t$ sb2$ seconds (the off-time). (2) Food waste--electroosmosis (continuous DC only) alone or in combination with expression (pressure of 207 kPa). (3) Titanium oxohydrate slurry--electroosmosis (similar to (1)) alone or in combination with a vacuum (absolute pressure of 89 kPa). (4) Pyrite slurry--electroosmosis (similar to (1)) in combination with vacuum (similar to (3)). The major independent variables were applied voltage, t$ sb1$ and t$ sb2,$ and initial bed height. The dependent variables were the amount of water removed and the electric current.For clay and titanium oxohydrate there was an optimum off-time for a fixed on-time. For $ rm t sb1=30$ s, the most water was removed from clay with $ rm t sb2=0.1$ s while for titanium oxohydrate the most water was removed for $ rm t sb2=3.5$ s. For suspensions (2), (3) and (4), the combination of electroosmotic dewatering with vacuum or expression increased the amount of water removed. In general, interrupted power removed more water than continuous power electroosmosis. For suspensions (3) and (4), only the combined modes were able to achieve dewatering targets set by industry.
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Sehnaoui, Karim. "Fouling of UV lamp sleeves : exploring inconsistencies in the role of iron." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31068.
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This paper investigates the effects of water quality parameters on fouling rates of UV lamp sleeves, through the results of various published studies performed by different groups as well as by the author.As part of this study, a pilot UV system was installed at the effluent line of two different biological wastewater treatment plants. The first plant included biofilters supplemented by alum addition during the summer for phosphorus removal. The second plant used an oxidation ditch and no coagulants were added. Iron was added to the UV pilot system influent in both cases to simulate post-coagulation of phosphorus. The Trojan UV System 3000 pilot consisted of three separate channels each containing 2 lamps. Two channels were used as controls by having just the sleeves (without UV lamps) in one of them and non-UV lamps (i.e. lamps with visible light output only) in the other. The third channel contained sleeves with two low-pressure UV lamps. The flow in each channel was maintained around 1--1.5 L/s and the ferric chloride concentration was varied from 0 to 6 mg/L. (Abstract shortened by UMI.)
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Lu, Dapei. "The performance and dynamics of fixed-film pressurized tubular bioreactors." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40183.
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A Fixed-Film Pressurized Tubular Bioreactor (FFPTB), which used the inner surface of a tube as the support surface, was evaluated under laboratory conditions to treat synthetic wastewater where glucose was used as the carbon source. Dissolved oxygen (DO) at the entrance of the tube was supplied in proportion to the influent chemical oxygen demand (COD) or total organic carbon (TOC) through a pressurized dissolution tank where compressed air or oxygen from a liquid oxygen cylinder was applied. Key variables included tube length and diameter, liquid flow rate, initial organic strength and gas pressure.The bioreactor was a coiled tube, 15 to 30 m long and 6.4 or 8 mm in diameter. It was a closed system operated under pressure at constant temperature (20$ sp circ$C) and pH (7.0). The hydraulic retention time (HRT) in the gas dissolution tank was 13 minutes, and the pressure applied was 210 to 350 kPa. The tube HRTs ranged from 16 to 38 minutes, and organic loadings from 2.29 to 11.46 g COD/m$ sp2$-d (the area being the inside surface area of the tube), depending on the liquid flows and initial waste concentrations.
The FFPTB performed well (80-85% organic removal) under COD loadings of up to 7.64 g/m$ sp2$-d at relatively short HRTs (40-45 minutes) using the compressed air supply. When pure oxygen was used, the raw wastewater with an initial COD varying between 80-120 mg/L could be treated with even higher efficiency (90-95% organic removal).
It was observed that the COD, TOC and DO decreased dramatically over the initial portion of the tube, then decreased more slowly. Biofilm thickness along the tube varied in similar fashion, with the greatest thickness (350-750 $ mu$m when the compressed air was used, and 1,900 $ mu$m with the pure oxygen supply) registered at the beginning of the tube and decreasing to 90 to 345 $ mu$m at the end. The biofilm thickness at the beginning of the tube was found to be proportional to the initial strength of the wastewater used. Furthermore, as the influent substrate concentration increased, the pressure had to increase appropriately to maintain a sufficient DO level for aerobic respiration in the system. The application of elevated pressures appeared to reduce the thickness of the liquid diffusion layer, thereby increasing the mass transfer rate, and consequently increasing the substrate utilization rate in the biofilm.
Besides the experimental investigations, a mathematical model based on Monod-type kinetics, molecular diffusion, liquid layer mass transport, bacterial growth and decay as well as shear stress under steady-state conditions was developed and verified for the FFPTB. Based upon numerical simulations, for a given bulk substrate concentration, the model would give a solution for substrate flux into the biofilm and predict the TOC concentration along the tube. The model was also able to predict the biofilm thickness along the tube with reasonable accuracy.
The system appears to be particularly suitable for high rate treatment of wastewaters, especially at low initial concentrations and for small systems. The high level of efficiency of the system could be achieved with short detention times and confined gaseous emissions as well as a low production of sludge.
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Dettmer, James William 1957. "Total organic halide and color removal from a kraft mill wastewater." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277839.
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Aerated stabilization basins (ASB) were modeled to examine the effects of operational modifications on their abilities to remove organic chlorinated compounds and color from Kraft mill bleaching wastewater. Color was measured spectrophotometrically and organic chlorinated compounds were measured as total organic halide (TOX). Kraft mill bleaching wastes were treated in bench-scale bioreactors containing acclimated sludge from operating full-scale ASB's. Modifications were made to traditional ASB operations to determine the effects of mixing, anaerobic conditions, sequential anaerobic/aerobic conditions, and forced co-mingling of wastewater and sludge on TOX and color removal. Results were compared to traditional facultative aerobic conditions experienced in an ASB. Performance was determined in terms of percent removal, total removal, and specific removal based on biomass present.
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Padival, Navnit Ajit 1966. "Mitigation of sewer crown corrosion via competitive inhibition of thiobacilli." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/278007.
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Inhibition of biogenic acid production by thiobacilli was investigated by encouraging the growth of potential competitors. Two-organism competition experiments (Thiobacillus sp. vs. heterotrophic competitor) were conducted in a bench-scale, continuous-flow reactor. Results were sensitive to the influent ammonia/glucose ratio. Under nitrogen-limiting conditions, the cell concentration of T. thiooxidans or T. neapolitanus and acid production rates were reduced by about two orders of magnitude. Under carbon-limiting conditions, only modest reductions in the thiobacilli cell density and effluent sulfate were observed. In general, encouragement of microbial competition can interrupt acid production by thiobacilli and may inhibit crown corrosion in concrete sewers.
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Paode, Rajendra 1961. "Ozone and peroxone induced particle destabilization, microflocculation and coagulant savings." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/278116.
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This research addressed the role of ozone and peroxone (ozone plus hydrogen peroxide) in particle destabilization, microflocculation, and as a coagulation aid at a pilot scale water treatment facility for Colorado River Water and State Project Water. Different treatment scenarios included: (i) alum, (ii) ozone/peroxone with alum, and (iii) ozone/peroxone with ferrous sulfate. While particle destabilization was observed at all dosages of ozone and peroxone, microflocculation was observed only at lower ozone dosages and the peroxone treatments. Ozone/peroxone plus alum treatments gave improved flocculation and overall filtered water quality. Pre-oxidation with 2.5 mg/L of ozone reduces alum requirements by 50 percent. Overall, in terms of particle destabilization and microflocculation and as a coagulation aid, peroxone performed better than ozone. FeSO4 appeared to be a more effective flocculant that alum.
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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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Fritz, Wolfgang U. "The effect of gas on general stability in wet landfills." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/290003.
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Due to regulatory legislation enacted over the past few decades, the design of municipal sanitary landfills has evolved from simple open dumps to relatively sophisticated storage and treatment facilities. Bioreactor landfills, which were first introduced in the mid 1990s became a popular landfill management technique and. A bioreactor landfill uses leachate recirculation to enhance the degradation processes thus degrading the waste constituents much faster than would be experienced with arid landfills. However, the well-accepted set of design criteria and methods of analysis for stability, settlement, degradation, gas generation, and water infiltration that had been developed for the arid landfills were not necessarily appropriate for the bioreactor landfills. Whether due to leachate recirculation or extreme precipitation, the waste in a landfill may tend to become saturated. The high saturation levels then reduce the permeability of the waste to landfill gas thus leading to pore pressures that are greater than what would be predicted by fluid statics. In this case, the factor of safety for global stability within the landfill will be lowered, potentially creating failure. A theoretical model predicting the time and depth dependent development pore pressures due to the formation of landfill gas in a wet landfill is presented. The model is then quantitatively approximated with a finite difference scheme. It was found that below the level of saturation, the steady state pressure distribution appears to be hydrostatic except that the unit weight of the fluid is significantly heavier (14.0 kN/m³) compared to water (9.81 kN/m³). In the ten days preceding July 10, 2000, approximately 0.75 m (30 inches) of rain fell onto the Payatas Landfill near Manila, Philippines. Results of HELP modeling indicate that this precipitation caused a 10-m deep zone of saturated waste at the bottom of the waste mass. Through a back-analysis of the failure, a factor of safety of 1.0 for stability was calculated by using an increased unit weight of pore fluid of 20.9 kN/m³, which is similar to that predicted by the finite difference scheme of 14.0 kN/m³. Hence, this research shows that the build-up of landfill gas can play a significant role in the stability of wet landfills.
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Hoffman, Daniel Eugene. "Predicting and Preventing Hydraulic Blow-Outs during High Velocity Jet Cleaning of Sanitary Sewer Lines." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1236010806.
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Lütkenhaus, Davidson. "Engineering understanding of cleaning : effect of chemistry and mechanical forces on soil removal." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7929/.
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The cleaning of food-based soils is highly relevant in domestic and industrial environments due to the costs associated with these operations as well as the significant consumption of time, water, and energy. Understanding the relationship between chemical and mechanical forces required to clean a surface is a critical step towards optimizing these processes. A complex twophase polymerized grease was developed and characterized with respect to its morphology, component distribution, and chemical composition. A thorough evaluation and physicochemical characterization of the cleaning process of this complex soil from a hard substrate was performed at two different length scales. Results showed that surfactants are more effective at weakening the cohesive interactions within the soil matrix and less effective in removing the adhesive bonds at the soil-substrate interface. A statistical model for cleaning efficiency was developed which described cleaning as a function of chemical and mechanical contributions. The effect of the chemistry on hydration and final cleaning performance was investigated through a definitive model screening and correlated to the tribological forces involved in the process. The model was shown to be applicable to several industrially relevant surfactant systems and revealed that hydration is the main factor driving cleaning of this two-phase soil.
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Avelino, Maria Clara Godinho Somer [UNESP]. "Construção de um sistema de alagados construídos e o comportamento dos parâmetros físico-químicos e biológicos da fase de maturação dos leitos de fluxo vertical." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/98307.
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avelino_mcgs_me_bauru.pdf: 1310267 bytes, checksum: 3759dbcf2bb00c77b6d84614fa3d81fd (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Esta dissertação de mestrado consistiu em elaborar e construir uma Estação de Tratamento de Esgoto (ETE) que utilizasse o sistema de Alagados Construídos (wetlands) para tratar o esgoto gerado no Departamento de Educação Física e da Moradia Estudantil, ambos ligados a Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP de Bauru. Para isso foi criado um sistema híbrido de fluxo subsuperficial horizontal seguido por outro de fluxo vertical, com recirculação. O projeto foi desenvolvido no campo da universidade para atender 91 habitantes equivalentes. Nesse trabalho, foram explorados as etapas construtivas da ETE e realizado análises físico-químicos e biológicos dos alagados construídos de fluxo vertical na fase de maturação do sistema. A elaboração deste estudo é uma ferramenta importante para o desenvolvimento do sistema de alagados construídos no Brasil, uma vez que, possibilita o conhecimento das técnicas de construção, manutenção e gastos para implantação de um sistema desse tipo
The realization of this research project is to develop and build a sewage treatment plant using the system of Constructed Wetlands to treat sewage generated in the Department of Physical Education and Student Housing, both linked to Universidade Estadual Paulista Julio de Mesquita Filho - UNESP in Bauru. For it was created a hybrid system of horizontal subsurface flow followed by another vertical flow, with recirculation. The project was developed at the university campus to meet 91 equivalent inhabitants. In this work were explored constructive steps ETE and testing of physico-chemical and biological of vertical flow constructed wetlands in the maturation phase of the system. The preparation of this study is an important tool for the development of constructed wetlands system in Brazil, since it enables the knowledge of construction techniques, maintenance and expenses fopr deploying such a system