Dissertations / Theses on the topic 'Water recycling'
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1
Rock, Channah, Jean E. McLain, and Daniel Gerrity. "Water Recycling FAQs." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2012. http://hdl.handle.net/10150/225869.
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Al-rifai, Jawad Hilmi. "Performance of water recycling technologies." Access electronically, 2008. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080918.125513/index.html.
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Rock, Channah, Jean E. McLain, and Daniel Gerrity. "Common Terminology of Water Recycling." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2012. http://hdl.handle.net/10150/225868.
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Kambanellas, Chrysostomos Andreou. "Water consumption and recycling of grey water in Cyprus." Thesis, University of South Wales, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333926.
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Lodge, B. N. "Membrane fouling during domestic water recycling." Thesis, Cranfield University, 2003. http://dspace.lib.cranfield.ac.uk/handle/1826/11067.
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The performance of a combined biological aerated filter (BAF) and an ultrafiltration
(UF) system for the treatment of real and synthetic greywater, settled sewage,
rainwater and borehole water has been assessed at both full-scale (at the Millennium
Dome Water Recycling plant) and bench-scale.
Irreversible membrane fouling was explained at bench-scale in terms of a simple but
novel model whereby a proportion of the membrane area is progressively blocked, in
proportion to the square root of the transmembrane pressure. This model provides a
link between irreversible fouling and reversible cake filtration theory, as the predicted
reduction in effective filtration area leads to increased solids loading on the unblocked
area. In addition, the bulk properties (specific cake resistance and compressibility) of
the filter cakes formed from biologically-treated real grey water and sewage were
found to be indistinguishable.
A statistical analysis of the results of longer term irreversible fouling trials at bench-
scale led to numerical relationships between fouling rate and process conditions.
These relationships facilitated the development of a process optimisation model, with
the dual-aim of maximising output and minimising chemical consumption.
At full-scale, a statistical technique was developed for calculating the relative fouling
propensity of three water sources (real grey water, rainwater and borehole water) that
were combined in the feed to a UP membrane. The technique was based on the
relative volumes of the three sources and the mean operating trans membrane pressure.
In addition, the impact of mechanical reliability on the financial viability of the full-
scale plant was investigated. A Net Present Value analysis revealed that the break-
even price (BEP) of the recycled water was reduced from £ 1.611m3 to £ 1.40/m
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through increasing availability from 73.8% to 91.2%, and this can be achieved by
investing in a targeted critical spares facility.
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Lodge, Benjamin Nicholas. "Membrane fouling during domestic water recycling." Thesis, Cranfield University, 2003. http://dspace.lib.cranfield.ac.uk/handle/1826/11067.
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The performance of a combined biological aerated filter (BAF) and an ultrafiltration (UF) system for the treatment of real and synthetic greywater, settled sewage, rainwater and borehole water has been assessed at both full-scale (at the Millennium Dome Water Recycling plant) and bench-scale. Irreversible membrane fouling was explained at bench-scale in terms of a simple but novel model whereby a proportion of the membrane area is progressively blocked, in proportion to the square root of the transmembrane pressure. This model provides a link between irreversible fouling and reversible cake filtration theory, as the predicted reduction in effective filtration area leads to increased solids loading on the unblocked area. In addition, the bulk properties (specific cake resistance and compressibility) of the filter cakes formed from biologically-treated real grey water and sewage were found to be indistinguishable. A statistical analysis of the results of longer term irreversible fouling trials at bench- scale led to numerical relationships between fouling rate and process conditions. These relationships facilitated the development of a process optimisation model, with the dual-aim of maximising output and minimising chemical consumption. At full-scale, a statistical technique was developed for calculating the relative fouling propensity of three water sources (real grey water, rainwater and borehole water) that were combined in the feed to a UP membrane. The technique was based on the relative volumes of the three sources and the mean operating trans membrane pressure. In addition, the impact of mechanical reliability on the financial viability of the full- scale plant was investigated. A Net Present Value analysis revealed that the break- even price (BEP) of the recycled water was reduced from £ 1.611m3 to £ 1.40/m 3 through increasing availability from 73.8% to 91.2%, and this can be achieved by investing in a targeted critical spares facility.
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Ng, Kwok-hung Wilson. "Environmental sustainability of grey water recycling in Hong Kong housing /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37117191.
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Stenekes, Nyree Civil & Environmental Engineering Faculty of Engineering UNSW. "Sustainability and participation in the governing of water use: the case of water recycling." Awarded by:University of New South Wales. School of Civil and Environmental Engineering, 2006. http://handle.unsw.edu.au/1959.4/28292.
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Urban water recycling has been promoted as one of several ways that water use efficiency could be improved in Australia???s cities, but few such schemes have been introduced. Many urban water-recycling schemes have been proposed, but often, these projects have been rejected because of community opposition. These difficulties suggest that recycling water is not just about having the right answer to any problem, but about the way in which the question is addressed. It is concerned with how practice is institutionalised; not just the rule making, but also the understandings and values that make the rule-making possible. In this thesis, the question of how the system of water governance could be strengthened to encourage sustainable water use through water recycling is examined. An analysis of experiences in three Australian case studies is conducted, in which recycled water was proposed for sustainability, to illuminate the way in which water use is institutionalised. Particular attention is given to the construction of meaning in relation to water use, by considering how water problems are framed and negotiated by different stakeholders and groups and the significance of the multiplicity of interpretive frameworks in use for the institutionalisation of practice. The analysis draws on institutional organisational theory and interpretive methods, which regard interpretation as one element (cognitive) in the stabilisation of social practice and closely linked to organisation (regulative) and values (normative). The study findings suggest meaning was a very important part of institutional change. Participants tended to construct policy issues as they became involved by drawing on different interpretive frameworks embodying different values and expectations. These interpretations reflected the organisational structuring of practice, such that the position/role in the organisational field reflected an actor???s interpretation of problems and/or solutions. Outcomes of the study suggest that institutionalising change in water management is problematic and depends on changes in the regulative, normative and cognitive dimensions of practice, as part of a continuous feedback loop between interpretation and practice. This view of change contrasts with existing research, which tends to see the problem in terms of influencing attitudes of specific groups and assumes preferences precede the action.
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Ng, Kwok-hung Wilson, and 吳國雄. "Environmental sustainability of grey water recycling in Hong Kong housing." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B4501355X.
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Cheruvu, Sarasija. "Novel membrane structure design for biomass harvesting and water recycling." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53885.
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Sustainable algae biofuel production is rising in demand, and the need to establish an efficient and proper algae harvesting method is extremely essential. Membrane filtration technology seems to be the most promising as a solid-liquid separation process. However, fouling seems to be the major problem for membranes. There is limited research on how to solve the problem of fouling, and cake buildup inside the membranes. A novel membrane design is required to solve the problem of fouling and cake buildup inside the membranes. The objective of this research is to construct a novel two way membrane design for algae biomass harvesting and water recycling. The methods used include culturing algae species, filtering them through the membrane module, and sample analysis for determining the water quality. The results show that the present filtration model had no fouling, or cake buildup as opposed to the previous filtration model. The present model permeate has a very low optical density of 0.007 absorbance at 750 nanometers. This result shows that permeate is completely devoid of algae.
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Marks, June Sylvia, and june marks@flinders edu au. "The experience of urban water recycling and the development of trust." Flinders University. Sociology, 2003. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20060123.214133.
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Water scarcity and water pollution are ongoing problems that require a rethinking of water use in the community. This calls for cooperation between the expert systems of water supply and sewerage as well as some level of public involvement. It is the interaction between the experts or providers, and the public as users or customers, that is the focus of this study on the experience of recycling water sourced from sewage effluent. This cross-national research explores the drivers behind water reuse; the way water reuse is presented to the public for consideration; the public response to water reuse; the influence of environmental and public health risk concerns; and the function of trust in the acceptance of potable water reuse and the sustainability of non potable reuse.
The absence of social science published literature relating to the experience of recycled water guided a grounded theory approach to this research, using a triangulation of methods for data collection and case study analysis. The social-psychological studies of Bruvold (1972-1988), located in water industry literature, were consulted to organise an audit of secondary, survey data obtained through industry contacts and fieldwork. In this way, acceptance of potable and non potable water reuse in the USA, UK and Australia is mapped to provide background data for a set of minor case studies that explore the experience of potable reuse.
Residential water reuse experience is investigated through embedded case study research. Primary data were collected at two residential sites in Adelaide and two in Florida. Recycled water is used for garden watering and toilet flushing at New Haven, and is planned for Mawson Lakes in Adelaide. Altamonte Springs and Brevard County in Florida recycle water for garden watering and outdoor uses only. Twenty residents were interviewed at each site involving semi-structured interviews: in-depth, face-to-face interviews in Adelaide and telephone interviews on site in Florida. Individual managers of the recycled water systems were also interviewed and, at New Haven, additional key stakeholders were consulted. Qualitative data analysis, employing a grounded theory approach, discovered the value of Sztompka�s (1999) framework for the �social becoming of trust�.
This research illustrates that the positive historical culture of trust at the Florida sites, coupled with robust structural support for residential water reuse that encourages positive provider-customer interactions, develops trust in non potable reuse and uses involving a higher level of contact. In the Adelaide sites, weak structural support induces reliance on informal structure that increases the public health risk, jeopardising the sustainability of residential reuse. In relation to potable reuse experience that centres on the Californian experience, a social dilemma is created through a strategic, marketing approach to public consultation and the lack of public communication on current water sources. Sztompka�s (1999) framework for trust as an ongoing process is expanded to include principles of public participation that will further consolidate trust in water reuse to achieve sustainable outcomes.
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Kadewa, Wilfred William. "Small-scale constructed wetland for onsite light grey water treatment and recycling." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/4572.
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This study focused on the investigation of the impact of household cleaning and personal care products on the quality of grey water and the assessment and optimisation of grey water treatment by a novel constructed wetland design. The prototype wetland design which comprised three-stage cascading beds (0.27 m 2 by 0.20 m deep) with sand media, (d10: 1.0 mm and d90: 4.0 mm) was tested for treatment performance to meet non-potable reuse standards in three versions, unplanted open beds, unplanted covered beds, and planted beds (comprising mixtures of Iris pseudacorus, Iris chrysographes, Carex elata Aurea and Mentha aquatica). The prototypes were benchmarked against a standard single-pass wetland (6 m 2 by 0.7 m) planted with Phragmites australis. Performance was measured in terms of removal of conventional water quality determinant parameters, as well as Total coliforms and E coli, and surfactants. Microbial dynamics were also monitored during the study by looking at variations in microbial compositions with time for the different wetlands. All the wetland versions effectively removed more than 98 % turbidity and organics meeting the most stringent reuse wastewater reuse standards of < 2.0 NTU and < 10 mg BOD5/L respectively. The influent grey water had low BOD:COD ratio ranging from 0.27 – 0.45, which is indicative of low biodegradability. The comparison of the cascade wetland performances showed the following: open beds > planted = covered, with the open beds version meeting reuse standards virtually throughout the monitoring period, despite recurrence of schmutsdecke in the top bed. All wetland technologies supported viable populations of microorganisms. Only phospholipid fatty acids (PLFAs) of lower carbon chain length (< C20) had concentrations greater than 1 mol %, in all the wetlands beds, confirming that the majority of the PLFAs in the media were from contribution of microbial organisms and not plant organic matter. Characterisation of microbial organisms was carried out to understand the constructed wetlands functioning and thus the treatment processes. The household products showed nutrient deficiency signifying low treatability. Product branding did not show correlation with any water quality parameters. In terms of toxicity, laundry and cleaning products were more inhibiting to soil microorganisms than were personal care products.
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Ko, Chi-ho. "A study of industrial waste water treatment and the feasibility of recycling /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17457749.
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Wanjiru, Evan. "Optimal energy-water nexus management in residential buildings incorporating renewable energy, efficient devices and water recycling." Thesis, University of Pretoria, 2017. http://hdl.handle.net/2263/61465.
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Developing nations face insurmountable challenges to reliably and sustainably provide energy and water to the population. These resources are intricately entwined such that decisions on the use of one affects the other (energy-water nexus). Inadequate and ageing infrastructure, increased population and connectivity, urbanization, improved standards of living and spatially uneven rainfall are some of the reasons causing this insecurity. Expanding and developing new supply infrastructure is not sustainable due to sky high costs and negative environmental impact such as increased greenhouse gas emissions and over extraction of surface water. The exponentially increasing demand, way above the capacity of supply infrastructure in most developing countries, requires urgent mitigation strategies through demand side management (DSM). The DSM strategies seek to increase efficiency of use of available resources and reducing demand from utilities in the short, medium and long term.
Renewable energy, rooftop rain water harvesting, pump-storage scheme and grey water recycling are some alternatives being used to curb the insecurity. However, renewable energy and rooftop water harvesting are spasmodic in nature hampering their adoption as the sole supply options for energy and water respectively.
The built environment is one of the largest energy and water consuming sectors in the world presenting a huge potential towards conserving and increasing efficiency of these resources. For this reason, coupled with the 1970s energy challenges, the concept of green buildings seeking to, among other factors, reduce the consumption of energy and water sprung up. Conventionally, policy makers, industry players and researchers have made decisions on either resource independently, with little knowledge on the effect it would have on the other. It is therefore imperative that optimal integration of alternative sources and resource efficient technologies are implemented and analysed jointly in order to achieve maximum benefits. This is a step closer to achieving green buildings while also improving energy and water security.
A multifaceted approach to save energy and water should integrate appropriate resource efficient technology, alternative source and an advanced and reliable control system to coordinate their operation.
In a typical South African urban residential house, water heating is one of the most energy and water intensive end uses while lawn irrigation is the highest water intensive end use occasioned by low rainfall and high evaporation. Therefore, seamless integration of these alternative supply and most resource intensive end uses provides the highest potential towards resource conservation. This thesis introduces the first practical and economical attempt to integrate various alternative energy and water supply options with efficient devices. The multifaceted approach used in this research has proven that optimal control strategy can significantly reduce the cost of these resources, bring in revenue through renewable energy sales, reuse waste water and reduce the demand for grid energy, water and waste water services.
This thesis is generally divided into cold and hot water categories; both of which energy-water nexus DSM is carried out. Open-loop optimal and closed-loop model predictive (MPC) control strategies that minimize the objective while meeting present technical and operational constraints are designed. In cold water systems, open-loop optimal and MPC strategies are designed to improve water reliability through a pump storage system. Energy efficiency (EE) of the pump is achieved through optimally shifting the load to off-peak period of the time-of-use (TOU) tariff in South Africa. Thereafter, an open-loop optimal control strategy is developed for rooftop rain water harvesting for lawn irrigation. The controller ensures water is conserved by using the stored rain water and ensuring only the required amount of water is used for irrigation. Further, EE is achieved through load shifting of the pump subject to the TOU tariff. The two control strategies are then developed to operate a grey water recycling system that is useful in meeting non-potable water demand such as toilet flushing and lawn irrigation and EE is achieved through shifting of pump's load. Finally, the two control strategies are designed for an integrated rain and grey water recycling for a residential house, whose life cycle cost (LCC) analysis is carried out. The hot water category is more energy intensive, and therefore, the open-loop optimal control strategy is developed to control a heat pump water heater (HPWH) and an instantaneous shower, both powered by grid-tied renewable energy systems. Solar and wind energy are used due to their abundance in South Africa. Thereafter, the MPC strategy is developed to power same devices with renewable energy systems. In both strategies, energy is saved through the use of renewable energy sources, that also bring in revenue through sale of excess power back to the grid. In addition, water is conserved through heating the cold water in the pipes using the instantaneous shower rather than running it down the drain while waiting for hot water to arrive. LCC analysis is also carried out for this strategy.
Each of the two control strategies has its strengths. The open loop optimal control is easier and cheaper to implement but is only suitable in cases where uncertainties and disturbances affecting the system do not alter the demand pattern for water in a major way. Conversely, the closed-loop MPC strategy is more complicated and costly to implement due to additional components like sensors, but comes with great robustness against uncertainties and disturbances. Both strategies are beneficial in ensuring security and reliability of energy and water is achieved. Importantly, technology alone cannot have sustainable DSM impact. Public education and awareness on importance of energy and water savings, improved efficiency and effect on supply infrastructure and greenhouse gas emissions are essential. Awareness is also important in enabling the acceptance of these technological advancements by the society.Thesis (PhD)--University of Pretoria, 2017.
National Hub for Energy Efficiency and Demand Side Management (EEDSM)
University of Pretoria
Electrical, Electronic and Computer Engineering
PhD
Unrestricted
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Rahman, Mokhlasur. "Health hazards associated with dissemination of bacterial strains in waste water recycling /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-468-6/.
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Graham, Taylor B. "Nitrate recycling versus removal in the Cape Fear River estuary." View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-3/grahamt/taylorgraham.pdf.
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Ko, Chi-ho, and 高志浩. "A study of industrial waste water treatment and the feasibility of recycling." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B31253398.
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Dzingai, Mathew. "The effect of ion accumulation owing to water recycling on flotation performance." Master's thesis, Faculty of Engineering and the Built Environment, 2019. http://hdl.handle.net/11427/31601.
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With the drive to reduce water usage globally, the mining sector must reassess its water usage as it has in the past contributed greatly to environmental degradation due to effluent discharge, tailing disposal and process water seepage into the water-table. Mineral beneficiation entails different unit operations; amongst them is froth flotation. Froth flotation is a multifaceted complex process which is water intensive and to manage water usage, the global mining industries are now recycling water. The recycled water may contain deleterious ions that affect the mineral surface, pulp chemistry and reagent action, hence the need to establish whether threshold concentrations exist beyond which the flotation performance will be adversely affected. This is of paramount importance in informing appropriate recycle streams and allowing simple, cost-effective water treatment methods to be applied. To better understand the influence of water recycling in flotation, a low-grade Cu-Ni-PGM sulphide ore was used. This study investigated the effects of increasing ionic strength as well as increases in specific ion concentrations to determine whether these selected ions had beneficial or deleterious effects on the flotation process. Copper and nickel were the target metals, floated as chalcopyrite and pentlandite, respectively. Their recovery and grade under different conditions was used as a measure to quantify whether a threshold ion concentration existed. The key performance indicators used were: (a) water recovery, (b) solids recovery, (c) valuable metal recovery, (d) grade of the recovered concentrates and (e) electrical conductivity. While a complex background water chemistry of 3 SPW was maintained for the spiking tests, ion spiking was intended to mimic the recycling of water and the most prevalent ions which would likely be recycled and therefore accumulated, such ions as: Ca2+, Mg2+, NO3 - , SO4 2- and S2O3 2-. These ions were chosen based on speculation from relevant literature that they might impact the flotation performance due to their influence on pulp chemistry and reagent interaction. This was achieved by conducting sequential batch flotation and electrical conductivity (EC) tests. Batch flotation tests were performed to investigate the effect of different ionic strength conditions on the overall flotation performance. The same ionic strengths and spiking concentrations were used for froth (or foam) column studies with a focus on tracking the ion concentration distribution between the froth and the slurry (or solution) by means of measuring the EC of each of the froth and the pulp (solution) phases. The differences implied whether the ions were selectively concentrated at the air-water or solids-water interphases in a 3-phase system or likewise at the v bubble surface or within the solution for a 2-phase system. This distribution of ions was linked to the other key performance indicators. Increasing ionic strength; 3, 5 and 10 SPW respectively, resulted in an increase in water recovery in the order 3 SPW < 5 SPW < 10 SPW, indicating an increase in froth stability due to inhibition of bubble coalescence at high ionic strength. There was, however, no significant effect on the valuable metal recovery. Most of the nickel was recovered in the copper circuit which was expected as on-site conditions were not maintained at the laboratory scale, no lime was added to adjust the pH in the copper circuit and an EDTA chelating agent was not included in the nickel circuit. Spiking 3 SPW with 800 ppm Ca2+ results in considerably higher water recovery per unit solids recovered compared to 3 SPW, 5 SPW, 400 ppm Ca2+, 350 ppm Mg2+, 700 ppm Mg2+. 400 ppm Ca2+ resulted in the highest copper and nickel grade and was deemed the threshold for this study while for Mg2+ threshold lies outside of the range considered for this study. 10 SPW shows a decrease in the copper and nickel grade while the copper and nickel recoveries were not significantly impacted. The presence of the Ca2+ and Mg2+ at high concentrations leads to gangue activation which as a consequence will result in decreased grade. 880 ppm NO3 - gave the highest copper and nickel grade compared to 3 SPW while increasing the S2O3 2- from 60 to 78 ppm resulted in an increase in nickel grade. 1200 ppm SO4 2- and 880 ppm NO3 - were deemed the threshold concentration for these anions, above which the flotation performance declines, while for S2O3 2- the threshold lay outside the range considered for this study. This study has shown that the accumulation of ions within plant water, owing to recycling, is, in general, beneficial to flotation. This study has also shown that there is a concentration for each ion beyond which it is no longer beneficial to flotation. While this finding is clearly ore and ion dependent, it gives an indication as to the need for water treatment and considering the threshold concentrations found, may direct operations to suitable treatment methods for their systems.
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Shipps, Hillary P. "Water Reuse as Part of San Diego's Water Portfolio." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/scripps_theses/144.
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San Diego imports 80 to 90 percent of its water supply, depending on conditions during any particular year. This high level of imports and low diversity of water supply have combined with climate change to generate an urgent need for increased conservation and diversification of San Diego's water supply. Water reuse is one option to mitigate this problem. An attempt was made in the early 1990s to recycle wastewater but the public reacted badly due to a combination of bad public relations, perceived environmental justice issues, and a psychological phenomenon called the yuck factor. With improved public relations and education, the project might go through this year.
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Surendran, Sundaralingam S. "The development of an in house greywater and roof water reclamation system for large institutions during 1994 to 1998." Thesis, Loughborough University, 2001. https://dspace.lboro.ac.uk/2134/6894.
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For sustainable water management, here is a necessity to consider alternatives, in addition to conventional systems. The aim of this research is to develop and demonstrate a sustainables, from and greywater reclamation system for WC flushing and it was started in 1994. In the UK there are no water quality standards for WC flushing water use. There were no design guidelines for greywater water reclamation and no published study on the supply-dernandb alance, in detail, for water recycling in institutions such as universities. The research has shown the feasibility of planned direct grey and storm water reclamation and recycling system to manage growing water and wastewater problems. This thesis is based on the information gathered from 4 universities, 3 hotels and 3 recreational centres, and experiences gained at Loughborough University during the development and demonstration of the full scale "in-house grey and roof water" reclamation and recycling systems. The water use, greywater quality and roof water characteristics were studied in detail and this information was used for the development of the reclamation and recycling system. The studies showed that the water usage at the university halls were not similar to usage in households. Unlike large water supply schemes, small in-house systems generate a large peak factor for water use. To avoid deficit, in addition to personal washing waters, a top-up of laundry wastewater or roof water, and a well-designed balancing tank is necessary. The demonstration study shows that there was no standby mains' water used, which means that the water reclaimed was sufficient for reuse. The quality characterisation study shows that the greywater and first flush storm water roof runoff were polluted. The characteristics of combined grey and roof water are suitable for biological treatment. Based on the infomation, a lab-scale unit was developed; the reactor characteristics and performance such as head losses and removal efficiency were monitored; and the unit was refined. Two novel multi-barrier reclamation systems were developed to achieve sufficient quantity and near potable quality of water with minimum maintenance and cost. During 1997 the grey and roof water recycling system with laboratory tested physical and biological reclamation processes without the use of coagulants and disinfection were installed. The performance of the treatment system was closely monitored until 1998. This provided benefits in near potable quality of reclaimed water, low head loss, reliability, failure free operation and simple maintenance. The reclaimed effluent from Project I and 2 met the UK/EU bathing water standards and was also able to meet the US EPA standards for WC flushing. The microbial (using coliform as an indicators) quality of reclaimed water without disinfection is acceptable for controlled recycling systems (carefully monitored and fully informed). There were no odour problems in the treated water or sludge blockages. Comparatively, Project I was more efficient at removing coliform, turbidity, solids (suspended, dissolved, volatile), and Project 2 better at removing carbon (organic and inorganic). A simple cost benefit analysis done for the recycling system at Royce Hall of Residence showed 10 years pay back. More detailed cost-benefit analysis including comparisons of new built and retrofit recycling system and fife cycle analysis are recommended. This study shows that most of the people questioned were accepted and were willing to consider using the recycling system for toilet flushing, if the water was clear, colourless, odour free, carried no risk and gave cost-benefits. During the demonstration stage the users willingly accepted non-potable grey water reuse.
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Pokorny, Alana O. "San Diego’s Options for Alternate Sources of Water: A comparative analysis of water recycling and desalination as alternative methods to importing water." Scholarship @ Claremont, 2015. http://scholarship.claremont.edu/scripps_theses/514.
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This paper describes the processes, methods, backgrounds, and economic challenges, of Desalination and Water Recycling and provide current examples of both. To create a baseline with which to compare the two methods, I will also delve into the history of California water policy. This complicated past is the reason water importation into Southern California remains the main method of obtaining water. Yet, as the current drought continues and technology advances, the need for imported water will become obsolete as the methods for recycling and desalinating water become less expensive, more convenient and more equitable. In the conclusion, all the methods will be compared and I will give suggestions on potential solutions for solving San Diego’s water dependence.
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Chang, Michael Field. "Water and Nutrient Recycling in High Rate Algae Ponds Fed in Primary Treated Municipal Wastewater." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1270.
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Algal biofuels present a promising future alternative to petroleum based fuels. Water nutrient recycling is a key step to increase the sustainability of algae biofuel production facilities. This thesis discusses the process of nutrient and water recycling in high rate algae raceway ponds (HRAP) fed primary treated municipal wastewater. Research was conducted primarily at the San Luis Obispo Water Resource Reclamation Facility (SLOWRRF). Nine 30 m2, 0.3 m deep HRAP’s were operated continuously from June 1, 2013 to April 17, 2014. The ponds were arranged in three sets of triplicate ponds, with two pond sets run on 3-day hydraulic residence time (HRT), and the third on a 2-day HRT. The biomass productivity of the 2-day HRT and 3-day HRT were compared. The two sets of 3-day HRT ponds were run in series to determine the effect on productivity associated with recycling growth media without supplemental nutrient addition. The first pond in series was referred to as round 1 and the second as round 2. Due to solids accumulation in the 2-day HRT ponds in summer proper biomass productivity values could not be determined. 4-inch standpipes were determined to cause the solids accumulation when large flocs were present in ponds. As a possible solution to the solids accumulation issue, a ramped standpipe was designed and installed in one pond per triplicate set. In winter the 2-day HRT pond was roughly 37% more productive than the 3-day HRT. In summer the round 1 (3-day HRT) ponds were roughly 33% more productive than the round 2 (3-day HRT) ponds. In winter the round 1 (3-day HRT) ponds were roughly 19% more productive than the round 2 (3-day HRT) ponds. The type of standpipe (ramped or 4-inch) did not cause a significant amount of solids accumulation in either of the 3-day HRT ponds. The type of standpipe did make a difference in the 2-day HRT ponds. On average the 4-inch standpipe pond had 35% higher TSS than the ramped standpipe ponds. In addition to these field experiments, laboratory aerobic degradation experiments were conducted to determine the nutrient release of previously digested sludge in aerobic ponds. Pretreatment of algae sludge did not have a significant effect on nutrient release of previously anaerobically digested algae sludge in aerobic conditions. The maximum soluble nitrogen generated in the aeration reactors was between 56% for the treated sludge, and 66% for the untreated sludge.
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Ikumapayi, Fatai Kolawole. "Flotation chemistry of complex sulphide ores : recycling of process water and flotation selectivity." Licentiate thesis, Luleå tekniska universitet, Industriell miljö- och processteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26634.
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Recycling of flotation effluents through the ore processing plant is one of the ways of reducing both plant-operating costs and industrial impact onto the local ecosystem. Such waters named acid mine drainage (AMD), if discharged from sulphide flotation are gypsum (CaSO4.H2O) saturated and have a high salinity (on the order of 1000 ppm). As minor species, they commonly contain reduced sulphur compounds (RSC) (sulfoxyanions with sulphur in the oxidation state below (VI) such as SO32-, S2O32-, S2O52-, and S4O62-), cations of ferrous and non-ferrous metals, frothing molecules, residual chemical reagents and products of their degradation. Tailing ponds also host communities of chemolithotrophic and heterotrophic microorganisms which play an important role in dictating their aqueous and solid phase chemical speciation. Consequently, the key step towards developing scientific approaches of recycling of the tailing waters is elucidation of how, in what extent, and why the tailing water components, taken singly or jointly influence flotation of sulphides. In this work, the influence of main process water components of calcium and sulphate on chalcopyrite, galena, sphalerite and pyrite flotation has been investigated through Hallimond flotation, zeta-potential and diffuse reflectance FTIR spectroscopy measurements using pure mineral samples as well as bench scale flotation tests using complex sulphide ore. The significance of process water species in flotation has been assessed using deionised water, process water and simulated water containing calcium and sulphate ions in experiments. In addition, the effect of temperature in bench scale flotation tests has also been examined. Hallimond flotation indicated depression of chalcopyrite, galena and sphalerite and activation of pyrite in the presence of calcium and sulphate ions with potassium amyl xanthate as collector. Calcium ions have significant influence on zeta-potential characteristics and xanthate adsorption behaviour of chalcopyrite, galena, sphalerite and pyrite compared to sulphate ions. FTIR studies revealed the presence of surface oxidised sulfoxy species and surface iron and calcium carbonates on chalcopyrite in the presence of process water and water containing calcium ions, surface oxidised sulfoxy and carbonate species on galena in the presence of deionised water, process water and water containing calcium and sulphate ions, hydrated surface oxidised species and surface iron and calcium carbonates on pyrite in the presence of process water and water containing calcium ions all at pH 10.5 in which the surface species influenced xanthate adsorption. The presence of surface oxidised sulfoxy and carbonate species on sphalerite were also revealed at pH 11.5 in the presence of deionised water, process water and water containing calcium and sulphate ions in which surface species does not influence xanthate adsorption. Bench scale flotation using two different complex sulphide ores showed that chalcopyrite recovery is better in process water than tap water and general depression of chalcopyrite at temperatures lower than 22oC in either tap water or process water, activation of chalcopyrite at all temperatures in process water and depression of chalcopyrite when tap water containing calcium and sulphate ions was used at 22oC. It also showed that galena recovery is better in tap water than process water and depression of galena at temperatures lower than 22oC in either tap water or process water. It also showed that sphalerite recovery is better in process water than in tap water better recovery of sphalerite at temperatures lower than 22oC in either tap water or process water.Godkänd; 2010; 20101114 (fatiku); LICENTIATSEMINARIUM Ämnesområde: Mineralteknik/Mineral Processing Examinator: Professor Kota Hanumantha Rao, Luleå tekniska universitet Diskutant: PhD Jaakko Leppinen, Outotec, Non-Ferrous Solutions, Espoo, Finland Tid: Fredag den 10 december 2010 kl 10.00 Plats: F531 Bergrum, Luleå tekniska universitet
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Bowen, Christian A. "Effects of Raceway Pond Water and Nutrient Recycling on Microalgae Production and Harvesting." DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1896.
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To be environmentally sustainable, algae biofuel production requires extensive recycling of water and nutrients during algae cultivation. Such recycling can be in the form of reuse of external wastewaters, such as from municipal sewers, but, to achieve significant biofuels production, internal recycling at the algae farms is also needed. A potential difficulty with internal recycling is the accumulation of auto-inhibitory compounds in recycled algae pond water. An additional concern is that nutrients in the residuals from algae biofuel manufacturing will be only partly bioavailable. Both these factors can limit the extent of internal recycling. Ultimately, combining external and internal recycling might be the most sustainable as long as these limiting factors are not excessive. Another important consideration in algae biofuel feedstock production is harvesting, which can be energy intensive and expensive. Bioflocculation of algae cells followed by sedimentation is a low input harvesting method, but one that might be affected by resource recycling. In the present 7-month study, algae productivity and settleability were measured for several types of water and nutrient recycling, using pilot raceways and tubes settler tanks fed municipal wastewater.
Two control raceway sets and two types of water and nutrient recycling raceway sets were operated concurrently. Each set was comprised of duplicate raceways (33-m2 surface area each, 0.3-m deep, 4-day hydraulic residence time with CO2 supplementation). One control set was fed primary clarifier effluent while the other control set was fed nitrified, filtered reclaimed wastewater. The two experimental raceway sets were fed different nutrients. One set received anaerobically-digested algal biomass (algae digestate) and the other set chemical fertilizer. Both recycling raceway sets were monitored to determine if water and nutrient recycling had any detrimental impacts on algal biomass growth.
Productivity was reported as gross and net in terms of volatile suspended solids (VSS). Gross productivity was based on raceway effluent biomass flow, which could be harvested for biofuel production. Net productivity was based on influent minus effluent biomass flows, which better represents algae growth. As a complement to the productivity data, measurements were made of indictors (salt, soluble chemical oxygen demand, and soluble UV absorbance) of potentially inhibitory substances and of nitrogen and phosphorus concentrations, which would have limited growth if they were too low.
After 7 months of continuous operation and 50 cycles of water reuse, the algae productivities of the water and nutrient recycling raceways matched or exceeded the productivities of the control raceways. Net productivities of the primary effluent-fed and reclaimed water-fed control ponds averaged 15.4 and 18.0 g-VSS/m2-day, respectively, while the digestate-fed and fertilizer-fed recycling ponds net productivities averaged 19.6 and 18.8 g-VSS/m2-day, respectively. The average standard deviation of the various duplicate sets ranged from 0.3 – 4.0 g-VSS/m2-day. These results do not indicate that algae were inhibited during the 7 months of continuous water recycling and digestate fertilization. In fact, the results suggest that recycling enhances productivity, although the statistical power of this experiment was low.
Indicators of potentially inhibitory substances were monitored during the experiment (salinity, soluble chemical oxygen demand, and UV absorbance). Only salt concentrations showed significant accumulation in the ponds, but not to concentrations expected to be inhibitory. A greater number of replicates and a longer experimental period are recommended in future experiments.
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Cultice, Alyssa Kristine. "Horticultural Producers' Willingness to Adopt Water Recycling Technology in the Mid-Atlantic Region." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/49455.
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Water-recycling technologies have been developed to reduce water consumption and surface runoff in horticultural operations. However, WRT may increase risk of disease from water-borne pathogens such as Pythium and Phytophthora. More information is needed about producers' management practices and attitudes regarding irrigation runoff containment and recycling. A mail survey was administered in February 2013 to horticultural nursery growers in Virginia, Maryland, and Pennsylvania. Collected were respondents' demographic characteristics plus irrigation and disease management practices. The survey incorporated a choice experiment quantifying willingness to adopt water recycling given hypothetical disease outbreak, water shortage probabilities, and percentage cost increases via a conditional logit model. Two hundred and sixty respondents provide valuable insight into horticultural production in the Mid-Atlantic region. We were unable to calculate the implicit price of water or disease for adoption because the sample of 91 respondents for the choice experiment yielded a flat distribution of operations ranging in $100 to $7 million in nursery cost. However, findings did support the hypothesis that producers will be more likely to adopt selected WRT when cost decreases, probability of disease decreases. Only 33% chose to adopt. Cost is the biggest factor as the majority of producers are not equipped to handle water recycling or capture and would go out of business due to the expense. Disease is also significant factor inhibiting growers from adopting. Until mandatory environmental regulations in place to force producers to contain runoff, or until incentivized cost sharing programs are implemented, wide spread adoption of water recycling technologies is unlikely to occur.Master of Science
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Tse, Pak-wing, and 謝柏榮. "A study of the applications of recycling rainwater in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31256004.
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Ormerod, Kerri Jean. "Governing Risk, Reuse, and Reclamation: Water Pollution Control and New Water Resources in the Southwestern United States." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/556485.
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The potential to supplement the potable water supply with highly treated municipal wastewater, or sewage, is of increasing interest to water managers and planners in many parts of the world. Seen as an option of last resort as recently as the late 1990s, today engineers commonly consider potable water reuse projects to be as safe as, if not safer than, conventionally sourced drinking water supplies. Nevertheless, only a few cities across the world intentionally augment drinking water supplies with highly treated wastewater. The objective of my dissertation is to examine the governance of potable recycled water planning to better understand how potable recycling projects emerge as a water management strategy. Political aspects of planned potable reuse are often recognized, and even lamented by water planners and industry experts. However, there is a paucity of research that empirically analyzes the political aspects that influence public decisions on potable water projects. This study asks: how are potable water projects made, shaped, and frustrated? To examine the governance arrangements of this emerging water management strategy this research project considers three critical issues: (1) public values and social pressure, (2) the political, legal, and institutional contexts, and (3) the role of subjectivity in defining facts, themes, and solutions. As part of this study I use Q Methodology to explore shared attitudes regarding the principles that should govern the future of planned potable reuse. The overall analyses support the notion that there is more than one way to understand and approach potable water recycling, and that socially-held viewpoints are informed by social-spatial practices. The results reveal two distinct "common sense" shared ways of thinking that pivot on ideas about the appropriate technology and reflect contested visions of ideal society. My dissertation is the first to apply Q Methodology to water recycling in the United States, and I use it to examine the subjective preferences of people who participate in water recycling operations or planning. Results indicate that there are at least two commonly held viewpoints concerning the future of planned potable water recycling, which I have labeled "neosanitarian" and "ecosanitarian." Drawing upon tenets established in the Progressive Era, neosanitarians strongly believe that potable water recycling is a safe, feasible, and appropriate way to expand urban water supplies. Drawing upon tenets established in ecology, ecosanitarians are not opposed to potable water recycling, however they are also interested in radical alternatives to the sanitary status quo. Both neosanitarians and ecosanitarians want to see a more sustainable approach to water planning, yet they disagree on what a more sustainable approach actually looks like in practice. For example, neosanitarians favor microfiltration and advanced wastewater treatment, while ecosanitarians prefer composting toilets and preventative actions. Both neosanitarians and ecosanitarians accept potable reuse as a workable solution, yet there are deep divisions between the two regarding the appropriate scale of technology, the proper level of public participation, and the root cause of water scarcity. While there is wide-spread agreement on certain ends (e.g., sustainability, potable reuse), there is serious disagreement about the appropriate the means to getting there (e.g., appropriate technology, level of public participation). The results illustrate how different "ways of seeing the world" contribute to the technological choices that define appropriate behavior, which, in turn, produces different kinds of communities and environments, and conditions the range of political possibilities.
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Bertrand, Nathalie Marie-Ange. "Impacts of scaling up water recycling and rainwater harvesting technologies on hydraulic and hydrological flows." Thesis, Cranfield University, 2008. http://dspace.lib.cranfield.ac.uk/handle/1826/4003.
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In recent years, the increasing awareness of scarcity of water resources, indications of likely climate variability, and the increasing pressure to use available fresh water resources more efficiently have together reinforced the need to look at infrastructure solutions with due regard to environmental considerations and social impacts, present and future. There is a vital need to apply an integrated approach to catchment management to implement sustainable solutions to resolve issues such as water supply and sewerage, drainage and river flooding. Many potentials solutions are available to control water demand and manage flood problems. Greywater recycling and rainwater harvesting are novel technologies. However, their catchment scale impacts on hydraulic and hydrological flows are poorly understood. The research aim is to identify the hydrologic and hydraulic impacts of scaling up such technologies at catchment scale. For this particular study, a computer simulation model will be used to evaluate how increasing urbanisation, climate change and the implementation of greywater recycling and rainwater harvesting may alter the water balance within a representative catchment. To achieve these aims data from the Carrickmines catchment in Ireland have been collected; a simulation model has been adapted to carry out the study, the model has been calibrated and validated, results have been analysed, and finally, a sensitivity analysis has been carried out. The results show that rainwater harvesting systems are comparatively more effective than greywater recycling techniques in reducing flood frequency and intensity. Under five year return period rainfall events, the implementation of rainwater harvesting at any scale and number of units is a useful technique to control river flow and floods. However, the study also shows that under extreme conditions the efficiency of rainwater harvesting systems decreases. The study concludes that implementing the two technologies within a single catchment is not a solution to several forms of hydrological problem. The study shows that implementing rainwater harvesting or re-use technologies are a very useful way to protect local freshwater reserves and therefore conserve our environment.
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Ayache, Chrystelle. "Impact of biological pre-treatment on membrane fouling and micropollutant rejection in water recycling." Thesis, Poitiers, 2013. http://www.theses.fr/2013POIT2256.
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Une des solutions alternatives les plus fiables contre la raréfaction des ressources en eau et la dégradation de leur qualité est la réutilisation des eaux usées. Aujourd'hui la technologie membranaire basse et haute pression s'impose comme la technologie de choix pour la production directe et indirecte d'eau potable du fait de la très haute qualité de l'eau produite. Néanmoins, le colmatage des membranes, affectant techniquement et économiquement les filières de traitement, reste aujourd'hui l'un des principaux défis. Les objectifs de cette thèse sont d'améliorer la compréhension du colmatage membranaire dans le recyclage des eaux usées en étudiant le rôle de la qualité de l'effluent secondaire sur le développement du colmatage et l'impact du colmatage sur la qualité de l'eau produite. Afin d'atteindre ces objectifs, une meilleure connaissance de la qualité des effluents secondaires et de leur impact sur les procédés membranaires s'avère indispensable. Les différentes fractions organiques des effluents ont été caractérisées à l'aide de techniques innovantes telles que la spectroscopie de fluorescence à 3 dimensions (EEM) et la chromatographie liquide couplée à une détection carbone (LC-OCD). Une unité à échelle pilote, composée d'ultrafiltration suivie d'une osmose inverse à deux étages, a été mise en place sur deux sites distincts. Plusieurs doses de monochloramine ont été testées (0 à 2 mg/L NH2Cl) afin de donner des recommandations d'optimisation de traitementOne of the most reliable alternative solutions to water shortage and scarcity in urban areas is potable reuse of what would otherwise be considered "waste" water. The combination of low and high-pressure membrane processes is the favoured technology for direct and indirect potable water recycling due to the very high water quality produced. Despite the fact that membrane technology is well established, membrane fouling remains a major challenge affecting plant operation technically and economically. This thesis aims to contribute to the understanding of membrane fouling in water reuse by investigating the importance of the feed water quality on fouling development and the impact of the fouling on the treated water quality. In order to achieve these objectives, it was important to develop better knowledge of the impact of feed water quality on the membrane process. The organic composition of the effluents was successfully differentiated with the use of advanced analytical tools such as fluorescence excitation emission matrix (EEM) and liquid chromatography-organic carbon detection (LC-OCD). To evaluate water quality impact on membrane fouling, a membrane pilot unit consisting of ultrafiltration and a two stage reverse osmosis train was operated on two different sites. Different monochloramine dosages (0 to 2 mg/L NH2Cl) were applied and their impact on RO membrane performance was studied in order to provide recommendations for plant design
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Humeníková, Juliana. "Aplikace membránových metod pro recyklaci pracích vod z pískových filtrů bazénové technologie." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-442870.
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The diploma thesis deals with the application of membrane processes for the treatment of washing water from sand filters of pool technology to parameters suitable for its reuse, not only on a theoretical level, but also on a real example. The experimental part deals with the monitoring of relevant parameters given by Decree no. 568/2000 Sb. and other technologically significant water quality indicators. All monitored parameters in the reverse osmosis permeate reached satisfactory values and thus it was concluded that the effluent water is suitable for reuse. Instead of being discharged into the sewer, it is possible to recycle 70 to 80 % of the washed water per day thanks to the applied technology, which saves approximately 20 m3 of water per day.
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Kieffer, Daniel W. "Feasibility of recycling air conditioner condensate for use as process water for a manufacturing facility." Oklahoma City : [s.n.], 2008.
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Cucarella, Cabañas Victor. "Phosphorus recycling from wastewater to agriculture using reactive filter media." Licentiate thesis, KTH, Land and Water Resources Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4449.
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This thesis focused on testing the suitability of reactive filter media used for phosphorus (P) removal from wastewater as fertilizers, thus recycling P to agriculture. The work compared the P sorption capacity of several materials in order to assess their suitability as a source of P for plants. The selected materials (Filtra P, Polonite and wollastonite) were saturated with P and used as soil amendments in a pot experiment. The amendments tended to improve the yield of barley and ryegrass compared with no P addition. The amendments also increased soil pH, P availability and cation exchange capacity in the studied soils. The substrates studied here can be of particular interest for acid soils. Of the materials studied, Polonite appears to be the most suitable substrate for the recycling of P from wastewater to agriculture
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de, Abreu Thomaka Carlos Fellipe. "Recycling of the water-phase from hydrothermal conversion of biomass : Comparative study of water composition using lignin and microalgae as feedstocks." Thesis, Umeå universitet, Kemiska institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184232.
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Conklin, Lorraine C. "Recycling and reusing a restaurant's waste : creating a sustainable small-scale urban farm." Virtual Press, 2006. http://liblink.bsu.edu/uhtbin/catkey/1355593.
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Urban sprawl, global warming and overused landfills are conditions around the world today, and while people are concerned about these issues they have few practical solutions to them. This creative project seeks to devise a way for a specific sector of business (restaurants), to have a practical way to help reduce global warming and waste while utilizing unused or under-used land in urban areas. While life cycle models are available that address such issues as these, very few case examples are actually in use in this country. Based on existing life cycle models, this project will seek to reuse the wastes from a restaurant and recycle them into a garden/greenhouse (called an urban farm throughout this paper) which will produce food for the restaurant. The three main waste categories from the restaurant to be looked at are the organic kitchen food wastes, water and the heat that is always being expelled from the kitchen while it is operation. Additional ways to make a restaurant more sustainable will also be given. This project will show what the benefits are when a sustainable system is in operation.Department of Landscape Architecture
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Brahmakulam, jacob Dany Paul, and Gustaf Johannesson. "Analyse and Improve Internal Water Treatment System at STENA Recycling : Master's Programme in Mechanical Engineering." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-37052.
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The thesis work is done at STENA Recycling Halmstad. The recycling facility has a yearly capacity to process 110.000 tonnes of material. There is an internal water system that circulates water to each of the separation processes and cleans before recirculation. Due to environmental concerns and government regulations the internal water cannot be let out of the facility. In addition, the internal water treatment system at STENA was not efficiently cleaning the internal water causing frequent plant maintenance issues. The aim of the thesis is to improve the quality of the cleaned water from the internal water system. Qualitative data such as interviews and observations were combined with quantitative data that is measurements to reach the results, using a method called triangulation. Six Sigma (DMAIC) model was followed for the work execution. The internal water treatment has five process steps. Five improvements are identified, implemented and evaluated. The thesis work goal of less than 2% dirt in the clean water is achieved by improving the overall performance of the cleaning system by 48.5% after implementing improvements. As a part of the last phase of six sigma approach which is control phase, an operation manual is developed to maintain the internal water treatment system.
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Östlund, Erik. "Impact of Water on Recycling Lithium Ion Battery Cathode Material in a Deep Eutectic Solvent." Thesis, Uppsala universitet, Strukturkemi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-417814.
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Nair, Divya Sreelatha. "Recycling Aquacultural Waste through Horticultural Greenhouse Production as a Resource Recovery Approach." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/31302.
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For intensive production systems like the Blue Ridge Aquaculture (BRA), based in Martinsville, VA, there are significant economic incentives to reuse the waste by diverting it into a cropping system that would increase the total productivity and total resource-reuse efficiency, and decrease the environmental, ecological, and financial costs of aquacultural waste disposal. In order to facilitate the reuse of effluent from the tilapia production at the BRA, a green house was developed. On this site, sludge waste from recirculating aquaculture was separated and composted using a vermicomposting technique and the resulting compost was utilized as an amendment to conventional greenhouse potting mixes. These aquacultural waste products were compared to conventional greenhouse culture of a common ornamental annual plant.
It was hypothesized that (1) vermicomposted aquaculture sludge would increase the growth of plants over conventional greenhouse potting mixes, and (2) recycled aquacultural wastewater can serve as a quality source of irrigation water, and plant response would differ with irrigation method. Plant growth and 11 out of 12 plant tissue nutrients were greater when compost was increased in the substrate. Plant root growth and 3 out of 12 tissue nutrients were increased when irrigated with wastewater. Plant shoot mass and total mass was greater when irrigated by ebb and flow irrigation compared to overhead mist irrigation, and 4 out of 12 tissue nutrients were greater when irrigated with mist irrigation. Overall plant performance was greatest with 15% vermicomposted sludge in the substrate and watered with wastewater by ebb and flow irrigation.
Master of Science
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Enongene, Godlove Nkwelle. "The enzymology of enhanced hydrolysis within the biosulphidogenic recycling sludge bed reactor (RSBR)." Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1015744.
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The hydrolysis of complex organic heteropolymers contained in municipal wastewater to simpler monomers by extracellular hydrolytic enzymes is generally considered the rate-limiting step of the biodegradation process. Previous studies of the Recycling Sludge Bed Reactor (RSBR) revealed that the hydrolysis of complex particulate organics, such as those contained in primary sludge (PS), was enhanced under anaerobic biosulphidogenic conditions. Although the mechanism was not fully understood, it appeared to involve the interaction of sulfide and sludge flocs. The current study was conducted using a 3500 ml laboratory-scale RSBR fed sieved PS at a loading rate of 0.5 kg COD/m³.day and an initial chemical oxygen demand (COD) to sulfate ratio (COD:SO₄) of 1:1. There was no significant accumulation of undigested sludge in the reactor over the 60-day experimental period and the quantity of SO₄ reduced indicated that the yield of soluble products from PS was at least as high as those reported previously for this system (> 50%). In the current study, the specific activities of a range of extracellular hydrolytic enzymes (L-alanine aminopeptidase, L-leucine aminopeptidase, arylsulphatase, α-glucosidase, β- glucosidase, protease and lipase) were monitored in a sulfide gradient within a biosulphidogenic RSBR. Data obtained indicated that the specific enzymatic activities increased with the depth of the RSBR and also correlated with a number of the physicochemical parameters including sulfide, alkalinity and sulfate. The activities of α- glucosidase and β-glucosidase were higher than that of the other enzymes studied. Lipase activity was relatively low and studies conducted on the enzyme-enzyme interaction using specific enzyme inhibitors indicated that lipases were probably being digested by the proteases. Further studies to determine the impact of sulfide on the enzymes, showed an increase in the enzyme activity with increasing sulfide concentration. Possible direct affects were investigated by looking for changes in the Michaelis constant (Km) and the maximal velocity (Vmax) of the crude enzymes with varying sulfide concentrations (250, 400 and 500 mg/l) using natural and synthetic substrates. The results showed no significant difference in both the Km and the Vmax for any of the hydrolytic enzymes except for the protease. The latter showed a statistically significant increase in the Km with increasing sulfide concentration. Although this indicated a direct interaction, this difference was not large enough to be of biochemical significance and was consequently not solely responsible for the enhanced hydrolysis observed in the RSBR. Investigation into the floc characteristics indicated that the biosulphidogenic RSBR flocs were generally small in size and became more dendritic with the depth of the RSBR. Based on the above data, the previously proposed descriptive models of enhanced hydrolysis of particulate organic matter in a biosulphidogenic RSBR has been revised. It is thought that the effect of sulfide on the hydrolysis step is primarily indirect and that the reduction in floc size and alteration of the floc shape to a more dendritic form is central to the success of the process.
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Smith, Matthew J. "The function of a green wall system when integrated with greywater treatment, recycling, and irrigation : exploration of water quality, water resources and planting media." Thesis, University of Reading, 2017. http://centaur.reading.ac.uk/77639/.
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Greywater of both treated (TGW) and untreated (GW) types are significant alternatives to mains water (MW) for sustaining the growth and expansion of green infrastructure. The aims of this thesis were first to evaluate GW and TGW as alternatives to MW for the purpose of irrigation of green walls and green roofs. Second, to determine whether irrigation water that has percolated through a green walls soil matrix can be further recycled and reused. GW was treated by a membrane bioreactor (MBR) and produced a high quality TGW, which met British Standards GW reuse requirements. A number of significant water quality improvements were achieved including the complete removal of bacterial species. Notably, GW turbidity was reduced from S.B±4.7 NTU to 0.6±0.2 NTU. Reduction in sodium (Na) concentrations were negligible or below limits of detection with inflow GW having 19.74±S.33 mg/l and outflow TGW 19.67±4.93 mg/1. Sodium was a constituent of particular interest since it is a key constituent of bathroom products as well as causing detrimental effects on soil and plant health in significant concentrations. Green wall irrigation trials showed that when comparing soils irrigated with synthetic GW and MW that no elevation ofsodium concentrations in the filtrate and soil samples was observed. The nutrient content and microbiological quality of green wall filtrate were influenced to a greater extent by its interaction with the soil matrix than the irrigation water type (synthetic GW, MW and TGW). Literary research has shown that GW irrigation ofsoils significantly reduced the SWHC (soil water holding capacity). The green walls irrigation trial results showed that the SWHC decreased by 24%, 23% and 20% when irrigated with synthetic GW, MWand TGW respectively. This demonstrates that the MW irrigation caused a SWHC decrease and that the additional decrease due to GW irrigation was only 1 %. Lightly loaded GW irrigation would not only allow for the replacement of MW but also provide filtered water, which can be collected and utilised. This project highlights a sustainable irrigation alternative to further integrated green walls into the urban environment. Results show that there was minimal effect of GW irrigation on soil, filtrate and leaf tissue in comparison to MW and TGW irrigation.
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Bair, Robert Alonso. "Development of a Decentralized and Off-grid Anaerobic Membrane Bioreactor (AnMBR) for Urban Sanitation in Developing Countries." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6174.
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Urbanization has led to rapid and uncontrolled growth of informal housing settlements in many developing countries. As most slum growth is unplanned, these areas tend to lack basic infrastructure including sanitation. The high user rates, lack of water and electricity infrastructure, space limitations, and scant financial resources make sanitation provision a major challenge in slums. As most decentralized sanitation technologies fail when applied in these environments, better technologies need to be developed that cater to the specific needs of slum dwellers. One promising technology, the membrane bioreactor (MBR) is routinely used in developed countries when a compact and resilient treatment system is required. However, the energy requirement of existing MBRs is high, as most are aerobic systems which require aeration. Anaerobic MBRs (AnMBR), which do not require aeration, have led to an improvement of the energy profile of MBRs. As research into the technology is still in its infancy, little is known regarding its applicability in high-density urban environments. This body of research is aimed at understanding the AnMBR’s treatment performance and overall reliability in challenging circumstances similar to those encountered in slums.
The appropriateness of an AnMBR was investigated with pilot and full-scale systems treating real wastewater in field conditions. The first investigation, discussed in Chapter 3, was used to determine the resilience of AnMBR treatment when subjected to periods of disuse and high fluctuations in incoming feed strengths. Decentralized systems often see much higher variations in feed composition than centralized systems as they lack large collection systems which homogenize the influent wastewater. Depending on the application, periods of low and no flow are also possible. During this long-term study it was observed that the membrane served an important role in controlling the effluent quality, especially when environmental conditions and feed characteristics varied so significantly as to upset biological stability. The system achieved an average COD removal efficiency of 88.2% throughout the study. It was also observed during this study that the system had higher removal efficiencies when treating higher COD concentrations. Higher strength wastewaters can routinely be found in decentralized applications where dilution water is minimal. These locations include water-efficient buildings, direct coupling to public toilets, and fecal sludge treatment plants. It was also found that the AnMBR was capable of rapidly recovering from extended periods of disuse. This ensures that the AnMBR can be applied to areas, such as schools and hotels that experience large seasonal variations and periods of disuse.
The second investigation, described in Chapter 4, examined how fluctuations in ambient temperatures affect fouling resistance. In small decentralized applications, operating the reactor at ambient temperatures is the most likely scenario, as controlling the reactor temperature would incur a high energy demand. Operating at ambient temperatures means that variations can be high, and that temperatures can drop below ideal ranges. Temperature is known to affect biological treatment and to a lesser extent membrane filtration, but the interactions between the two are not fully understood. To determine the effect of temperature on operation, a pilot scale AnMBR was used to treat wastewater with fluctuating ambient temperatures. Three trials were conducted during summer and winter conditions, as well an artificially heated period. It was found that membrane permeability can be greatly affected by operating temperature but its effect varied depending on the fouling state of the membrane. Virgin, or recently cleaned membranes were not affected by low temperatures, while the permeability of slightly fouled membranes was negatively correlated to changes in temperature. When slightly fouled, a membrane TMP could increase by 2.4 times with a 10oC drop in temperature. The magnitude of the TMP increase could not be explained by changes in water viscosity alone. The effect of temperature on TMP decreased when fouling became severe and normal operating pressures were high. These results suggest that seasonal adjustments to AnMBR operation would be necessary to prevent sharp and excessive increases in operational TMP during cold spells.
Chapter 5 investigated the feasibility of recovering water, nutrients, and energy in an off-grid and decentralized AnMBR. This investigation performed an energy, nutrient, and mass balance for a theoretical AnMBR treating water from a public toilet in a high density setting. What was concluded from this study is that complete water recycling can be accomplished in such an environment. Onsite water recycling would allow the system to be applied in arid urban areas as well as places lacking regular water provision. The study also concluded that the energy content of wastewater in a high density area would be sufficient to power an AnMBR and electronic toilet. For areas where low wastewater strengths would be expected, food waste addition to the wastewater would improve the energy profile of the system. As many urban areas of developing countries struggle with solid waste management, there is the opportunity to link food waste management with wastewater treatment. This study also highlighted the potential problems that ammonia and salinity buildup could have on a system that achieves complete water recycling.
Once the system specifically designed for urban areas was deemed theoretically feasible, a full-scale, solar-powered, prototypical system was constructed in Florida and tested in India (Chapter 6). This system, which was applied in Kerala, India, was investigated for its treatment and membrane performance as well as energy consumption. During the first four months of operation, the system was able to produce high quality product water that could be used for toilet flushing. This was achieved despite the low strength of the incoming feed water and higher than anticipated wastewater production rates. The wastewater strength was low due to the system’s application in a school setting and high levels of dilution water. The reliance on multiple anti-fouling mechanisms allowed the system to operate for 4 months without a significant change in TMP. The average energy consumption per unit of produced water depended on the amount of water treated per day. On average the energy consumption was 1.52 kWh/m3, but that value dropped to 0.83 kWh/m3 when volumes greater than 200 liters were treated per day. The lowest value measured during this trial was 0.16 kWh/m3 when 1,394 liters were produced. All of the energy used by the system was produced by onsite photovoltaics, with minimal carbon footprint. While the system was capable of meeting the water demand of the toilet system, further improvements in the energy demand of the system will be necessary to make the system more cost-effective, robust and reliable.
These results suggest that AnMBRs can be applied in high density urban areas for the dual objectives of wastewater treatment and resource recovery. Their reliable treatment in the face of large fluctuations in feed concentration, volume, and temperature suggests they are appropriate for decentralized applications. Membrane filtration allows water to be reliably recycled onsite with minimal operator oversight. The low energy requirements of the system allow for onsite renewable energy sourced, such as photovoltaics to be used to power the system. AnMBRs are able to address many of the challenges that traditional sanitation technologies cannot, which makes them a promising technology to address the problems encountered in slum sanitation.
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Joustra, Caryssa. "An Integrated Building Water Management Model for Green Building." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3654.
Full textAbstract:
The U.S. Green Building Council (USGBC) is the developer of the Leadership in Energy and Environmental Design (LEED™) green building scoring system. On first inspection of LEED points, few address water efficiency. However, water management encompasses other points beyond the Water Efficiency (WE) category. In general, the industry is apt to take a somewhat compartmentalized approach to water management. The use of alternative water sources or the reuse of wastewater significantly complicates the water budget picture. A total water management systems approach, taking into consideration water from various sources, both inside and outside the building, should be implemented in order to devise a strategy for optimal reduction of potable water consumption and wastewater generation. Using the STELLA software to create an integrated building water management (IBWM) model provides stakeholders with a tool to evaluate potential water savings under dynamic conditions for a specific project site. Data collection for IBWM model calibration also shows that water consumption trends are unique to each project, and using LEED assumptions about water usage can overestimate or underestimate potential water savings.
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Bloch, Jonathan Max. "Perspectives on reclaimed water among urban residents in Tampa, Florida." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0002839.
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Piovani, Laura. "Study of low environmental coating products: bio-based water products and solvent based products deriving from PET recycling." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Find full textAbstract:
In this study three different projects are presented.The first consist in the analysis of two different bio resins with which a white and a transparent water-based base coat, a transparent water-based top coat and a water-based hydro-oil are formulated, applied and characterized, replacing the fossil based resins. First, the two bio resins are analyzed in terms of compatibility with other resins, additives and solvents and then the products formulated are characterized in terms of viscosity and chemical resistances. After the application, the products are analyzed in terms of filming capacity. The second project consists in formulating a coating system using the bio resin, suitable for use on bamboo toothbrushes in order to avoid the formation of mold. In particular two different formulations with two different viscosities are tested after having subjected the toothbrush to different pre-treatments based on H2O2 30 volumes, saturated solution of AgNO3. The third project consists in the formulation of two solvent-based clear coating systems: a base coat with a matte top coat and a base coat with a glossy top coat. For both systems an alkyd resin is used, whose fatty acid part consists of olive fatty acids, containing 12-14% recycled PET. The two system are formulated, applied and characterized in terms of viscosity, specific weight, transparency, elasticity, sand ability and chemical resistances. A comparison is made with the same products produced using the fossil based resins.The results show that the products formulated using the bio resins have similar characteristics of the standard resins therefore the bio products can replace the fossil based one. The toothbrushes coated with the coating system using the two new formulations are more resistant to the formation of mold. Finally, the two solvent-based coating system formulated using a resin containing PET can replace a coating system formulated with fossil based resin as they present similar characteristics.
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Nnadi, E. O. "An evaluation of modified pervious pavements for water harvesting for irrigation purposes." Thesis, Coventry University, 2009. http://curve.coventry.ac.uk/open/items/f62c282d-4db2-21f3-4c30-7a77fe4d3def/1.
Full textAbstract:
The pervious pavement system has been identified as an effective source control device capable of removing urban stormwater pollution by trapping pollutants within the system and biodegradation. Recent studies have further demonstrated that the pervious pavement system could be used as a source of renewable energy capable of reducing household energy bill by about 80%. In view of ever increasing demand for water and the continued reduction in available fresh water resources in the world, stormwater has been recognized as a potential valuable source of water which could be harnessed. The overall aim of this multi disciplinary research was to evaluate the suitability of a modified pervious pavement system (PPS) for water harvesting and re-use, particularly focussing on potential third world applications and taking advantage of the latest developments in materials that are available for such applications. The aim was a holistic one in which water re-use was examined in terms of both the potential advantages from an irrigation point of view without ignoring the very important public health concerns that are often of concern when water is stored in circumstances which do not fit the normally used criteria for potable supplies. The results of this study confirmed the pollution control capability of the porous pavement system as earlier determined by previous studies. Also, a novel experimental rig was designed to reproducibly create very high and realistic rainfall events over model pavement structures. Furthermore, the performance of a new geotextile, Inbitex Composite® in the pervious pavement system was determined for the first time. Furthermore, this study also tested for the first time, the performance of a pervious pavement system modified by the incorporation of Inbitex Composite® geotextile with slits and made prescriptions as to how this new geotextile could be best installed in a modified pervious pavement system in order to achieve high infiltration without compromising pollution control. This study tested the practical use of the pervious pavement system for water harvesting and storage for reuse in irrigation. In order to achieve this, the author took what could be considered as a holistic approach to water quality issues and determined the chemical, electrochemical and microbiological quality of water stored in the system as well as investigated the public health concern of the potential of pathogenic organisms in waters stored in unconventional water storage system as the pervious pavement system. It also determined that the pervious pavement system have the capability to recycle water with physical, chemical and microbiological qualities that will meet international standards for irrigation and that the system does not offer a conducive environment for potential pathogenic organisms if contamination incident occurs from adjoining areas. This study also became the first to practically relate Sustainable Urban Drainage System (SUDS) to agricultural benefit by demonstrating how a SUDS device (pervious pavement system) could be used in addition to its urban drainage control role, as a source of supply of high quality irrigation water to cultivate crops fit for human and animal consumption despite high application of pollutants. This study determined contrary to the observation of earlier studies that the use of slow-release iv fertilizer could lead to eutrophication problems in cases where the water is channeled to natural water courses. Furthermore, active response of potential pathogenic bacteria to the presence of slow-release fertilizer was observed in this study. This raises a huge question on the need to add fertilizer to the pervious pavement system. Coupe, (2004) had demonstrated that oil degrading microbes would respond positively to food sources in the system and hence, there was no significant need for simulation by nutrient addition, the author concluded in the study presented here that fertilizer addition should only be conducted if the waters are to be used for irrigation where the nutrients would be beneficial to the plants and that even in this case, the microbiological water quality should be constantly monitored and the addition suspended if the risk of contamination from adjoining areas is high.
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Kleinschmidt, Ross Ivan. "Radioactive residues associated with water treatment, use and disposal in Australia." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/48058/1/Ross_Kleinschmidt_Thesis.pdf.
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Water resources are known to contain radioactive materials, either from natural or anthropogenic sources. Treatment, including wastewater treatment, of water for drinking, domestic, agricultural and industrial purposes has the potential to concentrate radioactive materials. Inevitably concentrated radioactive material is discharged to the environment as a waste product, reused for soil conditioning, or perhaps recycled as a new potable water supply. This thesis, presented as a collection of peer reviewed scientific papers, explores a number of water / wastewater treatment applications, and the subsequent nature and potential impact of radioactive residues associated with water exploitation processes. The thesis draws together research outcomes for sites predominantly throughout Queensland, Australia, where it is recognised that there is a paucity of published data on the subject. This thesis contributes to current knowledge on the monitoring, assessment and potential for radiation exposure from radioactive residues associated with the water industry.
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Bolondi, Elisa. "Circular water resource management in water-scarce regions. The case of the TANQIA Wastewater Treatment Plant in Fujairah (United Arabian Emirates)." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17823/.
Full textAbstract:
In the last decade, the importance of water for life and its sustainable management have become a central source of interest for governments and institutions. Water, like all the elements on planet Earth, is changing. The emerging global picture is that nearly a quarter of humanity already reside in water-scarce countries and water scarcity may proliferate to more regions.
In this scenery, one sustainable strategy is represented by the so-called circular water resources management or water recycling: an integrated management of the resources for implementing administration plans that consider the water reuse as an integrated step of the design process.
In the present work, the pilot project carried out at the TANQIA Wastewater Treatment Plant in Fujairah (U.A.E.) has been analysed. The project consists of a trial of two containerized pilot plants of about 15000 m3/year treatment capacity, that have been connected to the existing treatment line. This installation offers the possibility of testing, under real conditions, the capability of the units to produce clean water stripped of any contaminants that can be reused in unrestricted irrigation practices. The containers are equipped with ultrafiltration or nanofiltration membranes combined with an electrocoagulation unit, GAC filters and UV disinfection units. The combination of these multiple devices negates the need for any water treatment chemicals to be utilized.
Water safety and functional parameters have been monitored during the trial period of January 2019 and February 2019. The resultant effluent met the stringent standards of the World Health Organization (WHO) for unrestricted irrigation.
In the next two years, once that reliable water quality has been verified, the units will be manufactured pursuing an economical sustainable approach, in the UAE alongside other possible locations in the target markets of water-scarce, low-income countries across the MENA region.
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Cucarella, Cabañas Victor. "Recycling Filter Substrates used for Phosphorus Removal from Wastewater as Soil Amendments." Doctoral thesis, KTH, Mark- och vattenteknik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10204.
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This thesis studied the viability of recycling filter substrates as soil amendments after being used in on-site systems for phosphorus (P) removal from wastewater. Focus was put on the materials Filtra P and Polonite, which are commercial products used in compact filters in Sweden. A prerequisite for this choice was to review filter materials and P sorption capacity. The filter substrates (Filtra P, Polonite and wollastonite tailings) were recycled from laboratory infiltration columns as soil amendments to a neutral agricultural soil and to an acid meadow soil to study their impacts on soil properties and yield of barley and ryegrass. The amendments tended to improve the yield and showed a liming effect, significantly increasing soil pH and the availability of P. In another experiment, samples of Filtra P and Polonite were equilibrated in batch experiments with the two soils in order to study the P dynamics in the soil-substrate system. Batch equilibrations confirmed the liming potential of Filtra P and Polonite and showed that improved P availability in soils was strongly dependent on substrate P concentration, phase of sorbed P, and soil type. Finally, samples of Polonite used for household wastewater treatment were recycled as soil amendments to a mountain meadow and to an agricultural field for wheat cropping. The liming effect of Polonite was confirmed under field conditions and the results were similar to those of lime for the mountain meadow soil. However, the results were quite different for the agricultural field, where Polonite did not affect soil pH or any other chemical and physical soil properties investigated and had no impact on wheat yield and quality. The results from field experiments suggested that Polonite can be safely recycled to meadows and cropping fields at rates of 5-10 ton ha-1 but long-term studies are needed to forecast the effects of accumulation.QC 20100708
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Dowling, T. J. ""Sustainable development in water and sanitation" : a case study of the water and sanitation system at the Lynedoch Ecovillage Development." Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/1041.
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Thesis (M.Phil. (School of Public Management and Planning))--University of Stellenbosch, 2007.ENGLISH ABSTRACT: Water and sanitation is one of the key factors in the socio-economic development of a nation and people. Billions of people worldwide do not have access to clean water or basic sanitation leading to many health problems and developmental issues. This article discusses the challenges facing the world, South Africa and in particular the Western Cape and Cape Town in the provision of water and sanitation. For most people the desire is to have access to their own private portable water supply and their own private flush toilet connected via costly bulk water services to sewage treatment plants far away. The question posed is whether this model is sustainable into the future, given the water demands in many parts of the world affected by droughts and more violent weather cycles as a result of climate change and global warming. These factors will affect water supplies in South Africa and in particular the Western Cape and Cape Town. To answer some of the questions raised the Lynedoch EcoVillage development is discussed in detail in terms of sustainable neighbourhood planning and implementation. Sustainable Development is discussed, also various options in terms of applying ecological sanitation. The on-site water and sanitation system of the Lynedoch EcoVillage is discussed as a case study. The results of influent and effluent tests conducted by the CSIR are analysed to see whether the system is conforming to the Department of Water Affairs and Forestry standards for the use of effluent water in irrigation and re-use of water in toilets. Localised models of water and sanitation provision might thus be a way forward to satisfy the increasing demand for such services made on national and local authorities as urban areas increase in size and population.
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Liu, Chao-Yen, and 劉昭巖. "Water Recycling System for Floor Scrubber." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/67815138638367074196.
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碩士正修科技大學
電子工程研究所
102
This paper is focus on developing a wastewater recycling system that allows a single floor scrubber machine greatly enhance cleaning area, it not only can improve efficiency and save more power and operating time but also achieve environmental protection and water conservation purposes. Floor scrubber according to their system functions can be broadly divided into four parts, which are cleaning equipment, mechanical structure, electronic control systems and filtration circulatory system. Cleaning Equipment subsystems use scouring disk pads, round brush with cleaner, and the rear end of the blade with the suction device as a whole cleaning cycle. Electronic control subsystem uses programmable logic controller to drive the machine over a large area of cleaning, and control water filtration system to do the loop filtration, a filtration subsystem is added between the clean sink and sewage sinks. Let the filtered effluent flows back into the clear water tank to be reused. Can be combined with the completion of a regeneration program logic control sewage washing machine, a program logic control wastewater recycling for floor scrubber is completed. Optimal designs of each of the above systems are discussed in detail in the papers.
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Wu, Shiungming, and 伍祥銘. "The Synthesis And Recycling Of Water Cutting Fluid For Cutting Wafer." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/55027463052413491933.
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碩士義守大學
生物技術與化學工程研究所
100
The main purpose of this research is to study whether polyethylene glycol remains after cutting wafer in order to recycle and reduce the cost and raise its utility rate. We also explore polymerization of ethylene glycol and sulfuric acid to find the optimum synthetic conditions. We use Gel Permeation Chromatography (GPC), Fourier-Transform Infrared Spectrometer (FT-IR), Gas Chromatography-Mass Spectrometer (GC-MS) and Nuclear Magnetic Resonance Spectrophotometer (NMR) to characterize the commercial waterborne cutting fluid getting its components. Then, the commercial waterborne cutting fluid is used to compare with recycled waterborne cutting fluid. This results show that diethylene glycol is still rich in recycling the used cutting fluid. It reveals that the used cutting fluid can be reclaimed and reduce the cost. The used cutting waste fluid recycled from different solar wafer manufacturers are analyzed by GC-MS. It shows that the compositions of waterborne cutting fluid, alcohol and ether, are almost the same for different solar wafer manufacturers. The compound is composed of carbon-carbon backbone and hydroxyl end-group whose molecular weight is from 102 to 264. The analysis of GC-MS in cutting waste fluid recycled from different processes shows that centrifugation and filtration is better recycled method than flash distillation. Diethylene glycol can be got by cracking higher molecular weight of polyethylene glycol but the temperature should be controlled moderately. This cracking method can renew diethylene glycol efficiently and make it recycle again. The analysis of GC-MS for polymerization of ethylene glycol and sulfuric acid shows that ethylene glycol can be completely reacted in seven hours. However, the polymerization of ethylene glycol will cause violent reaction and get unwanted products if adding too much amount of catalysts. The optimum molar ratio of ethylene glycol and catalyst is 1:0.06. Most diethylene glycol and pentaethylene glycol can be synthesized if the reaction temperature is set 134℃. The yield will increase with raising reaction temperature because the ethylene glycol can be completely reacted.