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Artiola, Janick. "Water Facts: Home Water Treatment Options." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2011. http://hdl.handle.net/10150/146297.
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4 pp.Arizona Know Your Water.
Today, homeowners have access to several water treatment systems to help control minerals and contaminants and to disinfect their water. Nearly half of the homes in the U.S. have some type of water treatment device. Mistrust of public water utilities, uncertainty over water quality standards, concerns about general health issues and limited understanding about home water treatment systems have all played a role in this increasing demand for home water treatment systems. Private well owners also need to provide safe drinking water for their families and have to make decisions as to how to treat their own water sources to meet this need. However, choosing a water treatment system is no easy task. Depending of the volume of water and degree of contamination, the homeowner should consider professional assistance in selecting and installing well water treatment systems. The process of selection is often confounded by incomplete or misleading information about water quality, treatment options, and costs. The following paragraphs outline the major well water treatment options. Further details on types, uses (point of use) and costs of these home water treatment systems are provided in the Arizona Know Your Water booklet. Additional information about Arizonas water sources that can help private well owners make decisions about home water treatment options, can be found in Arizona Well Owners Guide to Water Supply booklet (see references section).
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Skibinski, Bertram. "Swimming pool water treatment with conventional and alternative water treatment technologies." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-233929.
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To mitigate microbial activity in swimming pools and to assure hygienic safety for bathers, pool systems have a re-circulating water system ensuring continuous water treatment and disinfection by chlorination. A major drawback associated with the use of chlorine as disinfectant is its potential to react with organic matter (OM) present in pool water to form potentially harmful disinfection by-products (DBP).
In this thesis, the treatment performance of different combinations of conventional and novel treatment processes was compared using a pilot scale swimming pool model that was operated under reproducible and fully controlled conditions. The quality of the pool water was determined in means of volatile DBPs and the concentration and composition of dissolved organic carbon (DOC).
Further, overall apparent reaction rates for the removal of monochloramine (MCA), a DBP found in pool water, in granular activated carbon (GAC) beds were determined using a fixed-bed reactor system operated under conditions typical for swimming pool water treatment. The reaction rates as well as the type of reaction products formed were correlated with physico-chemical properties of the tested GACs.
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Рой, Ігор Олександрович, Игорь Александрович Рой, and Ihor Oleksandrovych Roi. "The magnetic water treatment." Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/33564.
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There are many intensification destinations for water purification. The most common is the use of effective technological schemes, modernization and development of new methods. Their implementation in practice is not always possible due to technical, economic and other reasons.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/33564
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Morrison, Wilke. "Water treatment analysis guide." Master's thesis, Faculty of Engineering and the Built Environment, 2019. http://hdl.handle.net/11427/30896.
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The treatment of water up to potable/drinkable standards is a complex process, with many variables and parameters impacting on each other. In South Africa drinking water delivered to consumers must meet the requirements as recorded in the South African National Standards (SANS). Today, more so than ever, there are a number water sources that can be exploited and treated to provide safe drinking water, namely; surface water (dams and rivers), sea water, ground water and treated wastewater. The focus of this dissertation is on surface water; however, reference is made in the first sections with regards to sea water and ground water. The first step in designing a treatment process begins with analysis of the raw water source. Unfortunately, there is not a one size fits all approach and it is left up to the process engineer to find the correct method of investigation. This can be a daunting task, especially if lacking in experience and available information. The first part of this dissertation focusses on just that. It prescribes the method of sampling and aims to provide the reader with context on when to and what to test for. It goes further to suggest how the results may influence the process design and how certain contaminants can be removed. It also draws the attention to the sampling timeframe required, to obtain representative information, encompassing fluctuations in water quality. The second part of this dissertation describe the methods for designing a conventional water treatment system, comprising; aeration, coagulation, flocculation, dissolved air floatation, sedimentation, filtration and disinfection. It also comments on the water quality that warrants certain process steps to assist the process engineer in choosing the correct configuration. For most steps the design approach of two or more technologies are presented. This allows the process engineer to consider which technology best suits the application at hand. The design procedures are programmed into an, excel based, software model, which permits quick and easy design. A brief description of how the software model can be used is also covered. The results given by the software model is validated through a set of examples, appended to this document. Ultimately it is concluded that although this dissertation provides a guide for designing a treatment process it is not an encompassing tool that considers all the intricacies involved. That is, there are too many factors involved and considerations required, and cannot all be captured in one dissertation such as this. As such, it is finally recommended that any design attempts should be conducted by a suitably qualified and experienced process engineer that may use this dissertation to augment their design development.
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Keränen, A. (Anni). "Water treatment by quaternized lignocellulose." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526215143.
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Abstract Water-related problems are increasing globally, and new, low-cost technologies are needed to resolve them. Lignocellulosic waste materials contain reactive functional groups that can be used to provide a bio-based platform for the production of water treatment chemicals. Research on bio-based ion exchange materials in the treatment of real wastewaters is needed. In this thesis, anion exchange materials were prepared through chemical modification (epichlorohydrin, ethylenediamine and triethylamine) using five Finnish lignocellulosic materials as bio-based platforms. Scots pine sawdust and bark (Pinus sylvestris), Norway spruce bark (Picea abies), birch bark (Betula pendula/pubescens) and peat were chosen due to their local availability and abundance. The focus was placed on NO3- removal, but uptake of heavy metals, such as nickel, was also observed and studied. Studies on maximum sorption capacity, mechanism, kinetics, and the effects of temperature, pH and co-existing anions were used to elucidate the sorption behaviour of the prepared materials in batch and column tests. All five materials removed over 70% of NO3- at pH 3–10 (initial conc. 30 mg N/l). Quaternized pine sawdust worked best (max. capacity 32.8 mg NO3-N/g), and also in a wide temperature range (5–70°C). Column studies on quaternized pine sawdust using mining wastewater and industrial wastewater from a chemical plant provided information about the regeneration of exhausted material and its suitability for industrial applications. Uptake of Ni, V, Co and U was observed. Column studies proved the easy regeneration and reusability of the material. For comparison, pine sawdust was also modified using N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride and utilized to remove NO3- from groundwater and industrial wastewater. A maximum sorption capacity of 15.3 mg NO3-N/g was achieved for the synthetic solution. Overall, this thesis provides valuable information about bio-based anion exchange materials and their use in real waters and industrial applicationsTiivistelmä Edullisia ja kestäviä vedenkäsittelytekniikoita tarvitaan kasvavien vesiongelmien ratkaisemiseen. Lignoselluloosaa, kuten sahanpurua, syntyy suuria määriä teollisuuden sivutuotteena. Sen reaktiivisia funktionaalisia ryhmiä voidaan modifioida kemiallisesti ja valmistaa siten biopohjaisia vedenkäsittelykemikaaleja. Tutkimustietoa oikeiden jätevesien puhdistuksesta biopohjaisilla ioninvaihtomateriaaleilla tarvitaan lisää, jotta materiaalien käyttöä voidaan kehittää ja edistää. Tässä väitöstyössä valmistettiin anioninvaihtomateriaaleja modifioimalla kemiallisesti viittä suomalaista lignoselluloosamateriaalia: männyn sahanpurua ja kuorta (Pinus sylvestris), kuusen kuorta (Picea abies), koivun kuorta (Betula pendula/pubescens) ja turvetta. Menetelmässä käytettiin epikloorihydriiniä, etyleenidiamiinia ja trietyyliamiinia orgaanisessa liuotinfaasissa. Työssä keskityttiin erityisesti nitraatin poistoon sekä synteettisistä että oikeista jätevesistä. Materiaalien soveltuvuutta teollisiin sovelluksiin arvioitiin maksimisorptiokapasiteetin, sorptioisotermien, kinetiikka- ja kolonnikokeiden sekä pH:n, lämpötilan ja muiden anionien vaikutusta tutkivien kokeiden avulla. Kaikki viisi kationisoitua tuotetta poistivat yli 70 % nitraatista laajalla pH-alueella (3–10). Kationisoitu männyn sahanpuru osoittautui parhaaksi materiaaliksi (32,8 mg NO3-N/g), ja se toimi laajalla lämpötila-alueella (5–70°C). Kolonnikokeet osoittivat sen olevan helposti regeneroitavissa ja uudelleenkäytettävissä. Tuotetta testattiin myös kaivos- ja kemiantehtaan jäteveden käsittelyyn, ja kokeissa havaittiin hyviä nikkeli-, uraani-, vanadiini- ja kobolttireduktioita. Männyn sahanpurua modifioitiin vertailun vuoksi myös kationisella monomeerilla, N-(3-kloro-2-hydroksipropyyli)trimetyyliammoniumkloridilla. Tuotteen maksimisorptiokapasiteetiksi saatiin 15,3 mg NO3-N/g ja se poisti nitraattia saastuneesta pohjavedestä. Kokonaisuudessaan väitöskirjatyö tarjoaa uutta tietoa biopohjaisten ioninvaihtomateriaalien valmistamisesta ja niiden soveltuvuudesta oikeiden teollisuusjätevesien käsittelyyn
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Kazi, Noor Mohammed. "Pneumatic flocculation in water treatment." Thesis, Nottingham Trent University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283273.
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Välikangas, T. (Taru). "Secondary materials in water treatment." Master's thesis, University of Oulu, 2017. http://urn.fi/URN:NBN:fi:oulu-201702071114.
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In the World the availability of the clean drinking water is a serious problem. The appearance of this problem is different in developed and developing countries. Even though water treatment technologies are widely studied and improved, the developing countries do not have the same economic capacities to utilize the sufficient treatment methods. This thesis concentrates on the utilization of secondary materials in water treatment as adsorbents. These materials are potential for the low-cost treatment of water. For the testing of the secondary materials, two pollutants were chosen as model compounds: organic pharmaceutical diclofenac and inorganic arsenic As(V), since they have been recognized to be problematic in water treatment. Two industrial by-products were chosen as secondary materials to be tested as adsorbents. Sachtofer is a by-product from titanium dioxide TiO2 production and Red mud is a waste material originating from aluminium oxide Al2O3 production. Third material tested was sand from Brazil obtained via cooperation with the Federal Institute of Goias in Goiania, Brazil. In this thesis a commercial adsorbent CFH-12 (Kemira) was chosen as a reference material. The literature part of the thesis contains theoretical considerations on the utilization of adsorption in water treatment. In addition the effect of organic and inorganic impurities in water bodies are discussed in a general level. The experimental part of the thesis presents first the characterization results of the secondary materials. The specific surface areas (BET) were measured for all the secondary materials. The surface structures were studied with scanning electron microscopy (SEM). For some of the adsorbents, the pH of the point of zero charge was determined as well as the elemental composition with XRF. One part of this thesis concentrated on studying the effect of pre-treatment on the adsorption efficiency of the materials. In this case, the adsorption materials were washed with distilled water and treated with hydrochloric acid. The adsorption experiments were carried out as batch experiments. Diclofenac concentration during the experiments was analyzed with spectrophotometry and HPLC. The best removal, i.e. 16% of diclofenac was achieved with HCl-activated Brazilian sand. With Red mud the HCl-activated sample was the most effective with 8% removal. The HCl-activated Sachtofer removed only 4% of diclofenac. The change in the arsenic concentration during the experiments was analyzed by ICP-MS. With Sachtofer, all three pre-treated samples removed 100% of arsenic. All Red mud and Brazilian sand samples were able to remove arsenic in significant amount. Though, after HCl-activation, the removal of arsenic was higher giving 98% for Red mud and 100% for the Brazilian sand. The diclofenac removal was assumed to be difficult and the 16% removal was a quite good result. The problem seems to be too high pH. By adjusting pH to a lower level, the higher removal efficiency might be achievable. All arsenic removal results were promising, and with all the material samples the removal was higher than 90%. These results confirm that the secondary materials are potential adsorbents for in water treatment. With certain adsorbents, the removal was high even without any pre-treatment. This is economically interesting possibility that should be studied more, especially due to the possibility of improving the water treatment in developing countriesPuhtaan juomaveden puute on todellinen ongelma maailmassa. Se on ongelma jossa erityisesi kehittyvät ja kehittyneet maat ovat eriarvoisessa asemassa. Vaikka vedenpuhdistusprosesseja tutkitaan paljon ja ne ovat pitkälle kehittyneitä, ei kehittyvillä mailla ole välttämättä taloudellisia resursseja hyödyntää riittävää vedenpohditus tekniikkaa. Tässä työssä on tutkittu kierrätysmateriaalien hyötykäyttöä adsorbentteinä vedenpuhdistuksessa. Puhdistettaviksi malliaineeksi valittiin orgaaninen lääkeaine diklofenakki sekä epäorgaaninen arseeni As(V), koska niiden on havaittu aiheuttavan ongelmia nykyisissä vedenpuhdistusprosesseissa. Adsorptiomateriaaleina tässä työssä käytettiin teollisuuden sivutuotteina syntyneitä Sachtoferia joka on titaanidioksidin valmistuksen sivutuote, sekä punaliejua, joka alumiinioksidin valmistuksessa syntynyttä jätemateriaalia. Kolmantena materiaalina testattiin Brasilialaista -hiekkaa, jota saatiin tutkimustarkoituksiin yhteistyön kautta, Federal Institute of Goias, Goiania, Brasilia toimittamana. Työhön haluttiin valita myös yksi kaupallinen adsorptiomateriaali joka toimisi referenssimateriaalina, ja tämän vuoksi valitsimme adsorptiomateriaaliksi Kemiran CFH-12 -tuotteen. Työn kirjallisuus osiossa selvitetään adsorption teoriaa sekä sen hyödyntämistä vesienpuhdistuksessa. Myös orgaanisen ja epäorgaanisten haitta-aineiden vaikutuksia veden laatuun tarkastellaan yleisellä tasolla. Kokeellisen osan alussa työssä käytettyjen adsorbenttien ominaisuuksia tutkittiin erilaisilla menetelmillä, joilla arvioitiin materiaalien kykyä adsorboida malliaineita. Materiaaleille määritettiin mm. pH jossa materiaalin pintavaraus on nolla (point of zero charge). Lisäksi materiaaleille tehtiin BET-analyysi ominaispinta-alan selvittämiseksi ja niiden pintaa ja rakennetta tutkittiin elektronimikroskoopilla. Osalle aineista tehtiin myös alkuaineanalyysi. Työssä haluttiin myös tutkia vaikuttaisiko materiaalien esikäsittely adsorptiotehokkuuteen. Tämän vuoksi adsorptiomateriaaleja pestiin tislatulla vedellä sekä käsiteltiin suolahapolla. Adsorptiokokeet toteutettiin laboratoriomittakaavassa panoskokeina. Diklofenakin pitoisuutta seurattiin kokeen aikana spektrofotometrillä sekä HPLC analyysi menetelmällä. Paras tulos diklofenakin poistossa saatiin HCl -aktivoidulla Brasilialaisella hiekalla, jolloin poistuma oli 16 %. Punaliejulla käsitellyistä näytteistä paras poistuma, 8 %, saatiin myös HCl -aktivoidulla näytteellä. HCl -aktivoidulla Sachtoferilla poistuma oli vain 4 %. Arseenin pitoisuuden muutosta kokeen aikana analysoitiin ICP-MS menetelmällä. Kaikkilla kolmella Sachtofer -näytteellä arseenin poistuma oli 100 %. Kaikki punalieju ja Brasilialainen hiekka näytteet adsorboivat arseenia merkittävästi. Kuitenkin HCl -käsitellyillä näytteillä poistuma oli paras, punaliejulle 98 % ja Brasilialaiselle hiekalle 100 %. Diklofenakin poistamisen vedestä oletettiin olevan haastavaa, ja saavutettu 16 % poistuma oli hyvä tulos. Ongelmana diklofenakin poistossa oli todennäköisesti liian korkea pH ja mikäli pH:ta onnistutaan säätämään enemmän happamaksi, poistuma voisi olla korkeampi. Arseenin adsorptio kokeiden tulokset olivat todella lupaavia, ja kaikilla materiaaleilla poistuma oli vähintään 90 %. Näiden tulosten perusteella voidaan todeta että kierrätysmateriaalit ovat hyvin potentiaalinen vaihtoehto vedenkäsittelyadsorbenteiksi. Osa materiaaleista toimi arseenin poistossa tehokkaasti myös ilman esikäsittelyä. Tämä on taloudelliselta kannalta mielenkiintoinen tulos, jota tulisi tutkia lisää, erityisesti kehittyvien maiden vedenpuhdistuksen tehokkuuden parantamiseksi
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Hassinger, Elaine, Thomas A. Doerge, and Paul B. Baker. "Choosing Home Water Treatment Devices." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 1994. http://hdl.handle.net/10150/156940.
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1 pp.Water Facts: Number 7
There are many home water treatment manufacturers, dealers, and products in today's market. Choosing the best water treatment device for your home can be difficult. This article offers advice in choosing your home water treatment by discussing, the reliability, product performance, dealer reputation, and cost of installation.
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Hubler, David K. "Modeling Electrochemical Water Treatment Processes." Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/265367.
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Several electrochemical processes are modeled at process levels and atomic scales. Processes are presented for acid generation and ion exchange media regeneration, along with corresponding process models. Transport and reaction processes in individual ion exchange beads are also modeled. Acids of mild strength (pH = ~1-2) are generated from electrolyte solutions and their strength is effectively modeled as a function of time. The regeneration of ion exchange media is also modeled, to close agreement with measurements, and the process model is reconciled with a model for solute flux from an individual ion exchange bead. Together, the models show that the "gentle" regeneration process is controlled by the plating rate. Processes interior to the particle are controlled by diffusion, but all processes are faster than the characteristic time for plating. In a separate process, an electrochemical method is used to produce hypochlorite for disinfection. The process generates perchlorate as a toxic byproduct. Density function theory is used to construct an atomic-scale model of the mechanism for producing perchlorate, as well as the aging of the boron-doped diamond anode used in the process. The mechanism shows that the boron-doped diamond surface plays an important role in chemisorbing and stabilizing radicals of oxychlorine anions, allowing the radicals to live long enough to react and form higher ions like perchlorate. Wear mechanisms that occur on the anode are shown to oxidize and etch the surface, changing its chemical functionality over time. As the surface ages, the overpotential for water oxidation is decreased, decreasing the efficiency of the electrode.
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Esposto, Stefano. "Sustainable water treatment in emergency." Doctoral thesis, La Sapienza, 2006. http://hdl.handle.net/11573/916907.
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Chan, May Kwan Syuen. "Development of pillared clays for water and waste water treatment." Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/7757.
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Guerra, Garlito Rebeca. "The water treatment system at Djupdalen." Thesis, Karlstad University, Faculty of Technology and Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-1235.
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This is a project about The Water Treatment System at Djupdalen. The leakage water comes to the Water Treatment System from a deposition plant through the land. The leakage water is characterized by a high concentration of nitrogen and the system is based on biological removing of the nitrogen in the water, by nitrifying and denitrifying bacteria. Four different problems are found in the system: 1. High level of nitrogen concentration in the outgoing water of the system. It should be due to the lack of phosphate in the water, that do not let the bacteria to grow. 2. Low temperature during the most part of the year. Nitrifying and denitrifying bacteria are temperature-dependent, that are very slow at low temperatures. 3. High oxygen concentration in one of the anoxic pond, where the denitrification process take place. This oxygen concentration is too high for denitrifying bacteria to work. 4. The nitrification and denitrification bacteria need to be “old” to work efficiently. They need a surface to attach, because if not they flow with the water and they leave the system. And four possible solutions for the system are presented: 1. Phosphate should be added to the system to let bacteria growth. 2. Store the water at a store pond during the winter months and transport it to the system when the temperature is optimum for the bacteria to work. 3. Add carbon matter to improve the carbon oxidation and to low down the oxygen levels at the anoxic ponds. 4. Two options are presented to improve the system, the first one is based on the construction of a dark wavy bottom in the channel system, which will give a surface for bacteria to attaché, it will produce oxygenation in the water, and it will also improve the water temperature; and the second one is based on the addition of panels made of black material, which will give to bacteria a surface to attach, and improve the water temperature.
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Faccini, Johanna. "Sustainable treatment of perchlorate contaminated water." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37677.
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Perchlorate is a stable and soluble substance that can last for decades in the
environment. Studies have shown that it can reduce iodine uptake into the thyroid gland
which is of concern for people with decreased iodine intake, pregnant women and small
children. Perchlorate is removed from drinking water using highly selective ion exchange
(IX) resins that are replaced after exhaustion and incinerated or disposed in a landfill
since there are no viable methods for regenerating them. One of the major limitations in
regeneration of these single use resins is achieving complete desorption of perchlorate.
The sustainability of treatment processes for perchlorate contaminated water can be
achieved by regenerating the exhausted resin. A study on the adsorption and desorption
equilibrium, kinetics and biological regeneration of perchlorate from a trybutylamine
strong base anion (SBA) exchange resin was conducted. Adsorption and desorption
equilibrium could be described using the Freundlich model with estimated parameters
KF = 50 (mg/g)(L/mg)1/n and n = 2.36. The calculated average perchlorate-chloride
separation factor was 4700 ± 1700 and the resin capacity was 1.4 meq/mg. The kinetics
of adsorption and desorption of perchlorate from the resin were found to be controlled by
chemisorption since a pseudo-second order rate model fit the data the best.
The results from the physical/chemical studies were then applied to model the
biological regeneration of the resin using the culture NP30. Experiments conducted with
the exhausted resin inside a membrane to avoid direct contact with the culture,
demonstrated the biological regeneration of the resin by degradation of the desorbed
perchlorate. The model was able to describe the desorption and biodegradation of
perchlorate from the exhausted resin and the results were comparable to the experimental
data. The model was found to be sensitive to the Freundlich adsorption intensity
parameter n.
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PERES, FERNANDO ANTONIO SERRAPIO. "COOLING WATER TREATMENT USING HYDROGEN PEROXIDE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2006. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=8889@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOPERÓXIDOS DO BRASIL
O tratamento de águas de resfriamento normalmente é feito com a adição de cloro, porém este produto apresenta algumas desvantagens em sua aplicação. Como alternativa ao cloro, algumas indústrias no Brasil e no exterior estão começando a utilizar outros biocidas, dentre estes o peróxido de hidrogênio, um poderoso oxidante que apresenta forte ação biocida. O objetivo deste trabalho foi comparar a eficiência do cloro e do peróxido de hidrogênio como biocidas em diferentes condições, através de testes em água da torre de resfriamento de uma indústria siderúrgica localizada no Rio de Janeiro. A contaminação microbiológica desta água foi medida sem a adição dos biocidas e com a adição de cloro e peróxido de hidrogênio, permitindo assim comparar o desempenho destas substâncias no combate aos grupos bacterianos presentes na amostra. Foi realizado também um estudo sobre o efeito corrosivo destas substâncias através de testes de corrosão em aço carbono 1020, que permitiram avaliar a taxa de corrosão por perda de massa provocada pela aplicação destes produtos na água. Os resultados mostraram que o peróxido de hidrogênio possui uma ação biocida satisfatória para aplicações em águas de resfriamento. Foi constatado que o efeito biocida do peróxido de hidrogênio é mais limitado do que o cloro e que sua eficiência depende do tempo de contato e pode ser afetada pela presença de impurezas dissolvidas na água. Os ensaios de corrosão revelaram que o peróxido de hidrogênio provoca um efeito corrosivo comparável ao do cloro no material testado.
Cooling water treatment generally is made with the addition of chlorine, although it´s application has some disadvantages. There is an active development in Brazil and other countries to use alternative chemical disinfectants in place of chlorine, such as hydrogen peroxide, a powerful oxidant which is known for its high biocidal efficiency. The aim of this research is to study the effectiveness of hydrogen peroxide as a disinfectant compared to chlorine in different operational conditions. The experiments were carried out using an water sample from a cooling water system of a steelmaking plant in the city of Rio de Janeiro. The microbial contamination of this water sample was measured without adding any kind of disinfectant. After that, water sample was treated by adding hydrogen peroxide and chlorine, in order to compare and evaluate the efficiency of the two biocides to control bacterial growth in water. Besides microbiological tests, experiments were conducted to compare the degree of corrosion caused by the addition of hydrogen peroxide and chlorine in water. The experimental methodology employed 1020 carbon steel specimens and corrosion rates were measured by weight loss determination after the period of exposure. The results showed that the application of hydrogen peroxide leads to satisfactory bacterial control. However, compared to chlorine, hydrogen peroxide is a rather poor disinfectant. The efficiency of hydrogen peroxide depends on reaction time and it is affected by dissolved polluants in water. Evaluation of corrosion rates showed that hydrogen peroxide causes basically the same corrosion rates than chlorine.
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Zhao, Yiyi. "Non-thermal plasma for water treatment." Thesis, University of Strathclyde, 2017. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=28647.
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Plasma generated in contact with water has been extensively investigated in various electrode geometries and various discharge types for water treatment, of which the applications have been employed industrially on different scales. The reactive species such as OH radicals, O3, H2O2 and HO2 can be generated from the reactions that occur at the plasma-water interface. For discharges above water, the effect of positive gas ions, which lead to the formation of positive water ions, is considered the main pathway for OH radical formation; while for the discharge under water, the water dissociation by electron collisions is considered as the main pathway. However, the reaction zone for the production of reactive species (gas or liquid phase) is still controversial. This thesis presents a study of the plasma generated in the gas phase in contact with water by various discharge types for water treatment. The discharge characteristics, OH radical and H2O2 production, and solution conductivity and pH variation were investigated and compared under different experimental conditions. The degradation of methylene blue dye was investigated under DBD. The transition of impulsive current discharges into impulsive-diffuse discharges was recorded by increasing the solution conductivity; a further transition of the discharge type into a spark was recorded when the solution conductivity was increased to >2.4 mS/cm. The H2O2 energy efficiency of 1.1 g/kWh was recorded under positive impulsive current discharges in N2 and helium. The highest charge/H2O2 ratio of 1:1.26 was recorded under positive impulsive current discharges in O2 and N2. Under positive DC glow discharges, the H2O2 energy efficiency of 1.9 g/kWh was recorded in air discharges, and was slightly increased to 1.95 g/kWh when using a flow liquid electrode. Increased solution acidity and basicity from neutral solution have negative effects on H2O2 production. A significant amount of water vapour was observed under DC glow discharges, resulting in a negative effect on H2O2 production. Under negative discharges, no H2O2 production was detected in water after O2, N2, air and helium discharge treatments. In DBD, a threshold voltage is required to initiate electrical discharges between the glass plate and the water, through the micro-pores. The H2O2 production yield of 1.1 g/kWh was recorded in O2 discharge treatment. The degradation yield of methylene blue dye of 310 g/kWh was achieved within the first minute of O2 discharge treatment.
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Mouele, Emile Salomon Massima. "Water treatment using electrohydraulic discharge system." University of the Western Cape, 2014. http://hdl.handle.net/11394/4330.
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>Magister Scientiae - MScIn South Africa, water pollution problems have continued to increase due to increasing anthropogenic activities. The increasing number of organic contaminants in various water sources can be attributed to industrial development, population growth and agricultural run- off. These activities have impacted negatively on the availability and accessibility to sustainable clean water resources, exposing citizens to water borne diseases such as cholera, diarrhoea and typhoid fever; commonly reported among children. Advanced oxidation technologies such as dielectric barrier electrohydraulic discharge (EHD), also referred to as dielectric barrier discharge (DBD), have the ability to decompose persistent organics and eliminate microbes. DBD offers advantages such as efficiency, energy saving, rapid processing, use of few or no chemicals, and non-destructive impact on the ecosystem. The system is also capable of generating ozone, hydrogen peroxide, singlet oxygen, superoxide radicals, hydroxyl radicals and other active species. The combination of these reactive species has been reported to degrade biological and chemical pollutants rapidly and efficiently. In this study, the DBD system was optimized by investigating the effect of physico-chemical, electrical parameters and reactor configurations on Methylene Blue (MB) decolouration efficiency. The physico-chemical parameters included MB concentration, solution pH and conductivity, solution volume, NaCl electrolyte concentration in the electrode compartment and air flow rate. As for electrical parameters, the effects of voltage, electrode type and size on MB decolouration efficiency were studied. The effect of the aforementioned parameters on MB decolouration efficiency was assessed by varying one parameter at a time. The following physico-chemical parameters: time (from 0 - 60 minutes), pH (2.5 - 10.5), solution conductivity (5 - 20 mS/cm), MB concentration (0.5 – 10 mg/L), solution volume (500 – 2000 mL), NaCl electrode electrolyte concentration (10 – 50 g/L) and air flow rate (2– 4 L/min) were varied in their respective ranges under the applied experimental conditions: reactor air gap 2 mm, solution volume 1500 mL, NaCl electrolyte concentration of 50 g/L in the electrode compartment, voltage 25 V (7.8 kV), airflow rate 3 L/min, 0.5 mm silver electrode and a running time of 60 minutes. As for electrical parameters, voltage (from 20 - 25 V), electrode type (copper, silver and stainless steel) and electrode diameter (0.5 – 1.5 mm) were also altered individually at the applied experimental conditions. The reactor air gap was varied from 2 to 6 mm. At the same experimental conditions, the free reactive species generated mainly H2O2 and O3, were detected and quantified using the Eisenberg and indigo methods, respectively. The optimum physico-chemical parameters were found to be MB concentration 5 mg/L, concentration of NaCl electrolyte used in the central compartment of the DBD reactor 50 g/L, solution pH 2.5, solution conductivity 10 mS/cm, air flow rate 3 L/min, solution volume 1500 mL and an optimum contact time of 30 minutes. The optimum electrical parameters were found to be: applied voltage 25 and 1.5 mm silver electrode. The following parameters MB concentration, solution conductivity and pH, applied voltage and reactor configuration significantly affected MB decolouration efficiency compared to parameters such as solution volume, the inlet air flow rate, electrode type and size and NaCl electrolyte concentration in the electrode compartment, which were less effective in enhancing MB decolouration. Moreover, for all DBD experiments performed at the applied experimental conditions, complete decolouration of MB was achieved in the first 30 minutes. However, trends between the optimized parameters and MB decolouration efficiency were mostly observed after 10 minutes. The optimized DBD system reduced the treatment time from 30 to 20 minutes without any chemical additives. Moreover, at 5 mg/L MB under the applied optimum conditions, it was proved that besides 99% of MB decolouration reached after 60 minutes, 53% of total organic carbon (TOC) removal was also achieved. The chemical oxygen demand (COD) characterizing MB toxicity was less than 5 mg/L before as well as after the DBD experiment. After 10 minutes of experiment under the following conditions: Applied voltage 25 V, MB concentration 5 mg/L, solution pH (in between 6.04 and 6.64), solution volume 1500 mL, air flow rate 3 L/min, 0.5 mm silver electrode and a contact time of 60 minutes, about 3.73 x 10-5 mol/L H2O2 was produced which decreased to 2.93 x 10-5 mol/L 10 minutes later, while O3 concentration was initially very low and could not be detected. However, 0.5 mol/L of O3 was detected after 20 minutes of operating time, thereafter, H2O2 concentration decreased continuously with time while that of O3 fluctuated as the treatment time increased. Likewise, the energy density for the production of free reactive species reached 0.87 g/ kWh in the first 10 minutes due to the presence of chromophoric functional groups such as =N+(CH3)2 in MB structure that had to be destroyed. Thereafter, the energy consumption decreased progressively to zero with an increase in treatment time due to the destruction of =N+(CH3)2 groups in MB structure with time. The correlation between the rise in the of H2O2 concentration and energy density after 10 minutes was probably due to dissociation of OH- OH bonds in H2O2 by UV light to yield OH radicals which unselectively may have attacked MB dye. Thus, MB decomposition in the current DBD reactor was mostly initiated by H2O2 and O3. The irradiation of H2O2 by UV light generated in the DBD system was found to accelerate dye decomposition in the first 30 minutes of the experiment. The UV-vis analysis of treated MB samples confirmed that the complete decolouration of MB achieved in the first 30 minutes was due to the destruction of the chromophoric [=N+(CH3)2] group in Methylene blue structure, while the FT-IR confirmed the presence of traces of various functional groups such as C=C, C=O, C=N, NH, NH3, NO2, etc. characteristics of carboxylic acids, amines, amides, nitrogen based compounds (salts), aliphatic and unsaturated by-products remaining in the bulk solution after treatment. The salts analysis after treatment showed that 16 mg/L of nitrates and nitrites and 1.1mg/L of sulphates mainly originating from air and MB decomposition were present in the treated samples. The EHD/DBD system used in this study offers an approach to partially treat water/wastewaters and its optimization was able to significantly enhance the decomposition of the target MB dye as indicated by the reduction of total organic carbon (TOC) from 8.3 mg/L to 3.9 mg/L. Compared to previous research, this study successfully optimised a complete double cylindrical dielectric barrier discharge (DBD) reactor at ambient condition without any chemical additives.
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Srinivasan, Rangesh. "Treatment of Microcontaminants in Drinking Water." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1242775351.
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Londeree, Danielle Julia. "Silica-titania composites for water treatment." [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000564.
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Siddiqui, Mohamed Shakeel. "Ozone-bromide interactions in water treatment." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185847.
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Ozonation of drinking waters, particularly as a preoxidant, is becoming a widespread practice. Ozone is a powerful oxidant and reacts with many of the natural constituents present in water. The presence of bromide ion in water can lead to the formation of brominated disinfection by-products upon ozonation. The existence of brominated by-products in a public water supply could be of public health concern since some of them have been shown to be mutagenic. Production of both organic and inorganic by-products upon ozonation of waters containing bromide ion was investigated. Organic by-products identified include bromoform, dibromoacetonitrile (DBAN), and 1,1(DBAA); inorganic by-products identified include bromate, hypobromous acid and hypobromite ion. Formation of by-products is a function of bromide ion concentration, the source and concentration of humic substances, pH, ozone dose, temperature, alkalinity and reaction time. Bromoform concentration ranged from 5 to 60 $\mu$g/L and total organic bromine (TOBr) concentration varied from 15 to 150 $\mu$g/L for a bromide concentration ranging from 0.5 to 1.5 mg/L. TOBr concentrations were much higher than bromoform indicating that bromoform constitutes only a fraction of the pool of brominated DBP material. Bromate threshold levels were shown to vary according to precursor source and pH level. At pH 7.5 bromide threshold concentrations for bromate were higher than at pH 8.5; the exact opposite case was observed for bromoform. Ionic strength had no significant effect on the formation of by-products whereas an increase in alkalinity resulted in decreased amounts of by-products. Temperature effects are manifested in two different ways: (i) the water temperature at which ozonation was carried out versus (ii) the subsequent incubation temperature. While enhanced precursor oxidation was observed at higher ozonation temperatures, the partial oxidation by-products varied in their reactivity in forming brominated by-products upon incubation. An increase in incubation temperature from 20 to 30$\sp\circ$C produced about a 30% increase in bromoform where as an increase in ozonation temperature resulted in a 20% increase in bromoform. Results of this research indicate that control of by-products can be effected by using PEROXONE (hydrogen peroxide plus ozone) or ammonia. PEROXONE produced 55% less organic by-products at the cost of a 25% increase in bromate. Ammonia addition resulted in a 30% decrease of both organic and inorganic by-products.
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Gerlach, Kyle T. "Assessment of Ferrate for Pre-Oxidation Treatment of Harmful Algal Blooms in Drinking Water Treatment." Digital WPI, 2019. https://digitalcommons.wpi.edu/etd-theses/1332.
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Harmful algal blooms in surface water supply systems pose a threat to public health and are increasing in both frequency and geographical distribution. Cyanobacteria can contribute to taste and odor issues and potentially release harmful cyanotoxins into the water. Several treatment methods are currently employed to control these blooms, including physical separation and chemical pre-oxidation. However, existing oxidation options can be costly; increase the release of intracellular material causing the formation of disinfection byproducts; or disrupt coagulation and filtration processes. This study investigated ferrate (Fe(VI)) as an alternative to other oxidants by measuring its effect on algae cells. Fe(VI) has several advantages as an oxidant, including a high oxidation potential, a low potential for harmful disinfection byproduct production, and formation of Fe(III) - which can potentially be beneficial for downstream treatment processes. Bench scale studies were conducted with laboratory prepared waters containing the common cyanobacteria Microcystis aeruginosa to examine the interactions between Fe(VI) and algae. The effects of ferrate oxidation on algae were characterized by particle counts, UV254 absorbance, total organic carbon (TOC) and dissolved organic carbon (DOC), and total nitrogen. Ferrate decomposition was also monitored. Results showed that Fe(VI) lysed algal cells under some conditions, but further oxidation of released organic matter is possible at some doses. Additionally, some coagulation benefits were observed through an overall decrease in total particle counts and an increase in particle sizes. In general, the results indicate that Fe(VI) could be a possible alternative to other oxidants for water utilities during harmful algal blooms; however, the final fate of resulting organic matter and the potential for disinfection byproduct formation should be further studied.
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Rose, Joan Bray. "Virus removal during conventional drinking water treatment." Diss., The University of Arizona, 1985. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1985_473_sip1_w.pdf&type=application/pdf.
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Mehta, Sahib, and Sahib Mehta. "Thermal Driven Water Treatment Systems for Full Separation of Solute-Water." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/621124.
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This work encompasses the study of a novel thermal driven desalination system to accomplish full separation of water and solute. This process advantageous over other process because it involves zero recirculation and zero liquid discharge, thus having minimum environmental impact. Since this system provides full separation, salts and other valuable products can be obtained in addition to pure water. This system can operate at high energy efficiencies using medium temperature heat source like industrial reject or solar cells. This plant consists of two technologies, the full separation and multi effect distillation which when integrated together 8ive us water and salt separately. Three different configuration of the FS-MED system have been presented, naming concurrent feed, variable feed, and counter current feed. They vary depending on their flow and feed distribution. Numerical procedure has been developed to solve the energy and mass balance equation for steady state condition has been presented.
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Bergman, Lauren E. "Predicting Water Treatment Challenges From Source Water Natural Organic Matter Characterization." Research Showcase @ CMU, 2016. http://repository.cmu.edu/dissertations/781.
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Natural Organic Matter (NOM), a pervasive component of natural waters, presents many challenges for water treatment systems. Its complex and heterogeneous nature makes NOM difficult to characterize and highly variable in its effect in water treatment. Two specific water treatment challenges caused by NOM and dependent on its character are disinfection by-product (DBP) formation and organic fouling in pressure-driven membranes. Many NOM characterization methods exist and have shown success in highly controlled laboratory settings; however, evaluating their effectiveness in full-scale systems to predict DBP formation and membrane fouling remains an ongoing challenge. Fluorescence NOM Excitation Emission Matrices (EEM) are hypothesized to be effective in NOM characterization because they capture the complexity and heterogeneity of the NOM in data-rich measurements that are unique to each individual sample. The objective of this work was to assess the utility of fluorescence EEM and other NOM characterization techniques for predicting DBP formation and membrane fouling in full-scale treatment systems. The review of current literature on NOM characterization and use in predicting water treatment challenges revealed patterns among NOM characterizations and water treatment outcomes – namely, high molecular weight, hydrophobic, aromatic NOM leads to increased DBP formation, while hydrophilic NOM with low aromaticity leads to increased organic fouling. Multiple reports from laboratory studies indicating the success of fluorescence measurements in characterizing DBP formation and membrane fouling suggest evaluation at full-scale treatment plants is warranted. The two field studies presented in this dissertation each address one of the major treatment challenges outlined – DBP formation and membrane fouling. The DBP formation field study incorporated source water and finished water samples from six treatment plants along the Monongahela River in southwestern Pennsylvania to create a regional watershed model. Fluorescence measurements of the source water were used successfully to classify finished water DBPs according to various targets using classification trees. The membrane fouling study incorporated samples of the raw source water and treated water at various treatment stages within a full-scale two-pass (two-stage) reverse osmosis membrane treatment plant. Fluorescence measurements were successful in distinguishing between high fouling and low fouling periods within the plant, however, they were not capable of tracking treatability of source water throughout the pre-treatment steps. The results of the two field studies indicate that fluorescence measurements have utility in NOM characterization for full-scale treatment plant operations, but more research is needed in determining which specific signals are useful in online fluorescence detection and in assessing the broader applicability of these techniques to other geographical regions with different water qualities.
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Johansson, Per-Erik. "Solar powered water treatment : Examining solar evaporation as a sustainable water treatment method in rural areas in Ghana." Thesis, Karlstads universitet, Avdelningen för energi-, miljö- och byggteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-30012.
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Since the currently used method of supplying clean drinking water to the Ghanaian population consists of selling water sachets of 0.5 liter, there is a major ecological problem due to plastic contamination of the environment. The relatively high water price of buying these sachets also causes economic problems for a large portion of the population.To reduce the consumption of plastic as well as the resulting environmental contamination and the financial burden on low-income citizens, which represents a greater portion of the population, a new method for solar-powered water was evaluated as a sustainable water treatment method in rural areas in Ghana.To test this method a prototype was constructed, based on a combination of the principles of solar desalination plants and common solar collectors, and was tested on site in Ghana.This thesis consists of a field study and a computer simulation. The field study in turn consists of an investigative and experimental study in which the investigative portion sought to find the possibilities and costs of constructing more plants in on site. This is of great importance for getting a clear picture of what economic impact the plant has on the sustainable development.In the experimental study the prototypes treatment capacity was examined, regarding Coliform bacteria, arsenic, iron, and chloride as well as its effect on the pH level of the water. The study also examined how much water the prototype can produce in a day and, in conjunction with the investigative study, to what extent this could reduce the use of plastic bags.The simulation part of the thesis examined possible improvement of the prototype and evaluated the influence of various factors on its overall effectiveness.The study showed that the prototype, which measures 92x68x18cm, where able to produce about 3 liters of drinking water per day (equivalent to 6 sachets of water) and managed to remove all measured contaminants from the treated water, without any change in the pH value.Då den i nuläget vanligaste metoden att distribuera rent dricksvatten i Ghana består av försäljningen av vattenpåsar á 0,5 liter, finns det stora ekologiska problem till följd av plastkontaminering av miljön. Det relativt höga vattenpriset som tillkommer av att köpa vatten på påse orsakar även ekonomiska problem för en stor del av befolkningen.För att minska konsumtionen av plast såväl som den resulterande föroreningen av miljön och den ekonomiska belastningen på befolkningen, undersöktes en ny solvärmedriven metod för vattenrening som en möjlig hållbar vattenreningsmetod i landsbygdsområden i Ghana.För att utvärdera denna metod konstruerades en prototyp, baserad på en kombination av principerna bakom soldrivna avsaltningsanläggningar och vanliga solfångare, som testades på plats i Ghana.Examensarbetet består av en fältstudie och simuleringsdel. Fältstudien består i sin tur av en undersökande och en experimentell studie, där den undersökande delen såg över möjligheterna och kostnaderna av att konstruera fler anläggningar på plats. Detta är av stor vikt för att få en klar bild över vilka ekonomiska effekter anläggningen har på den hållbara utvecklingen.I den experimentella studien testades prototypens reningsförmåga med avseende på koliforma bakterier, arsenik, klorid och järn samt dess effekt på vattnets pH värde. Det undersöktes även hur mycket vatten prototypen kan producera under en dag, och i samband med den undersökande studien, hur mycket detta skulle kunna minska användandet av plastpåsar.Simuleringsdelen av arbetet genomfördes för att undersöka möjliga förbättringsåtgärder av prototypen samt utvärderat olika faktorers inverkan på prototypens effektivitet.Studien visade att prototypen, som mäter 92x68x18cm, kunde producera ca 3 liter dricksvatten per dag (motsvarande förbrukningen av 6 påsar vatten) och klarade att rena vattnet från alla undersökta föroreningar, utan någon förändring av vattnets pH värde.
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Kong, Kong Hang. "Chemical aspects of coagulation in water treatment." Thesis, University of Macau, 2000. http://umaclib3.umac.mo/record=b1445036.
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Franklin, Guy Sinclair. "Novel iron precipitates for drinking water treatment." Thesis, Imperial College London, 1999. http://hdl.handle.net/10044/1/8351.
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Brookes, Adam. "Immersed membrane bioreactors for produced water treatment." Thesis, Cranfield University, 2005. http://dspace.lib.cranfield.ac.uk/handle/1826/4508.
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The performance of a submerged membrane bioreactor for the duty of gas field produced water treatment was appraised. The system was operated under steady state conditions at a range of mixed liquor suspended solids (MLSS) concentrations and treatment and membrane performance examined. Organics removal (COD and TOC) display removal rates between 90 and 97%. Removal of specific target compounds Benzene, Toulene, Ethylbenzene and Xylene were removed to above 99% in liquid phase with loss to atmosphere between 0.3 and 1%. Comparison of fouling rates at a number of imposed fluxes has been made between long term filtration trials and short term tests using the flux step method. Produced water fed biomass displays a greater fouling propensity than municipal wastewater fed biomass from previous studies. Results indicate an exponential relationship between fouling rate and flux for both long and short term trials, although the value was an order of magnitude lower during long term tests. Moreover, operation during long term trials is characterised by a period of pseudo stable operation followed by a catastrophic rise in TMP at a given critical filtration time (tfi, ) during trials at 6 g. L"1. This time of stable operation, tfit, is characterised by a linear relationship between fouling rate and flux. Results have been compared with the literature. Data for membrane fouling prior to the end of t fit yielded a poor fit with a recently proposed model. Trends recorded at t> trlt revealed the fouling rate to follow no definable trend with flux. The system showed resilience to free oil shocking up to an oil concentration of 200ppmv. Following an increase in oil concentration to 500 ppmv, rapid and exponential fouling ensued.
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Verrelli, D. I. "Drinking water treatment sludge production and dewaterabilityф." D. I. Verrelli, 2008. http://repository.unimelb.edu.au/10187/3521.
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The provision of clean drinking water typically involves treatment processes to remove contaminants. The conventional process involves coagulation with hydrolysing metal salts, typically of aluminium (‘alum’) or trivalent iron (‘ferric’). Along with the product water this also produces a waste by-product, or sludge. The fact of increasing sludge production — due to higher levels of treatment and greater volume of water supply — conflicts with modern demands for environmental best practice, leading to higher financial costs. A further issue is the significant quantity of water that is held up in the sludge, and wasted.One means of dealing with these problems is to dewater the sludge further. This reduces the volume of waste to be disposed of. The consistency is also improved (e.g. for the purpose of landfilling). And a significant amount of water can be recovered. The efficiency, and efficacy, of this process depends on the dewaterability of the sludge.In fact, good dewaterability is vital to the operation of conventional drinking water treatment plants (WTP’s). The usual process of separating the particulates, formed from a blend of contaminants and coagulated precipitate, relies on ‘clarification’ and ‘thickening’, which are essentially settling operations of solid–liquid separation.WTP operators — and researchers — do attempt to measure sludge dewaterability, but usually rely on empirical characterisation techniques that do not tell the full story and can even mislead. Understanding of the physical and chemical nature of the sludge is also surprisingly rudimentary, considering the long history of these processes.
The present work begins by reviewing the current state of knowledge on raw water and sludge composition, with special focus on solid aluminium and iron phases and on fractal aggregate structure. Next the theory of dewatering is examined, with the adopted phenomenological theory contrasted with empirical techniques and other theories.The foundation for subsequent analyses is laid by experimental work which establishes the solid phase density of WTP sludges. Additionally, alum sludges are found to contain pseudoböhmite, while 2-line ferrihydrite and goethite are identified in ferric sludges.
A key hypothesis is that dewaterability is partly determined by the treatment conditions. To investigate this, numerous WTP sludges were studied that had been generated under diverse conditions: some plant samples were obtained, and the remainder were generated in the laboratory (results were consistent). Dewaterability was characterised for each sludge in concentration ranges relevant to settling, centrifugation and filtration using models developed by LANDMAN and WHITE inter alia; it is expressed in terms of both equilibrium and kinetic parameters, py(φ) and R(φ) respectively.This work confirmed that dewaterability is significantly influenced by treatment conditions.The strongest correlations were observed when varying coagulation pH and coagulant dose. At high doses precipitated coagulant controls the sludge behaviour, and dewaterability is poor. Dewaterability deteriorates as pH is increased for high-dose alum sludges; other sludges are less sensitive to pH. These findings can be linked to the faster coagulation dynamics prevailing at high coagulant and alkali dose.Alum and ferric sludges in general had comparable dewaterabilities, and the characteristics of a magnesium sludge were similar too.Small effects on dewaterability were observed in response to variations in raw water organic content and shearing. Polymer flocculation and conditioning appeared mainly to affect dewaterability at low sludge concentrations. Ageing did not produce clear changes in dewaterability.Dense, compact particles are known to dewater better than ‘fluffy’ aggregates or flocs usually encountered in drinking water treatment. This explains the superior dewaterability of a sludge containing powdered activated carbon (PAC). Even greater improvements were observed following a cycle of sludge freezing and thawing for a wide range of WTP sludges.
Further aspects considered in the present work include deviations from simplifying assumptions that are usually made. Specifically: investigation of long-time dewatering behaviour, wall effects, non-isotropic stresses, and reversibility of dewatering (or ‘elasticity’).Several other results and conclusions, of both theoretical and experimental nature, are presented on topics of subsidiary or peripheral interest that are nonetheless important for establishing a reliable basis for research in this area.
This work has proposed links between industrial drinking water coagulation conditions, sludge dewaterability from settling to filtration, and the microstructure of the aggregates making up that sludge. This information can be used when considering the operation or design of a WTP in order to optimise sludge dewaterability, within the constraints of producing drinking water of acceptable quality.
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Chowdhury, Zaid Kabir. "Coagulation of submicron colloids in water treatment." Diss., The University of Arizona, 1988. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1988_35_sip1_w.pdf&type=application/pdf.
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Engin, Guleda. "Development of anionic clays for water treatment." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342253.
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Byman, Lina. "Treatment of wash water from road tunnels." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171816.
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Tunnels have become increasingly important in the development of road networks to meet rising transportation demands. Washing of road tunnels must be performed regularly to ensure traffic safety. The washing procedure generates significant amount of polluted wash water. Before discharge to a receiving water body, treatment is necessary to avoid potential degradation of the water quality. In this study, 12 in situ sedimentation experiments were conducted to evaluate treatment efficiency of sedimentation, with and without the addition of chemical flocculent. The findings showed that untreated tunnel wash water was highly polluted with total suspended solids (804-9690 mg/l), PAHs (0.4–29 μg/l) and heavy metals. Most pollutants were associated with the particulate material. Significant correlations (r2 > 0.95) were found between suspended solids and metals. Efficient removal of pollutants was possible by sedimentation with addition of flocculent. Within 20 hours of sedimentation low concentrations were reached of suspended solids (<15mg/l), PAHs (<0.1 μg/l), Cd (<0.05 μg/l), Cr (< 8 μg/l), Hg (<0.02 μg/l), Pb (<0.5 μg/l) and Zn (< 60 μg/l). The results confirm the possibility to treat tunnel wash water with sedimentation and flocculation and to discharge treated wash water to a recipient, provided particular attention is given to very sensitive water bodies.
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Young, Candice. "Biosand filtration in household drinking water treatment." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121334.
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Household water treatment technologies provide an interim solution to drinking water provision in areas which are not yet serviced by a continuous piped connection to a communal treated source. This is a critical problem in Amerindian communities in the Guyanese hinterland region, where remote location and low population density make improving environmental health infrastructure challenging. Biosand filtration is one promising household water treatment technology available for this purpose. The overall goal of this research was to better understand, and thus improve, the biosand filter for field operation. A field study was performed in the Amerindian community of St. Cuthbert's, Guyana. A questionnaire was implemented to determine risk factors for diarrhoeal disease, and water samples were taken from creeks and standpipes in the village and from stored drinking water in households. Serving drinking water by scooping from a bucket as opposed to pouring or using a tap or spigot was found to be a risk factor for illness, while having water piped to the household was associated with lower diarrhoeal disease rates. Post-collection water contamination was found to cause a significant decline in drinking water quality. Adoption and sustained use of biosand filters were compared to two other prominent household water treatment methods, that being the addition of hypochlorite solution and use of a safe water storage container, and ceramic candle filtration. It was found that in St. Cuthbert's bios and filters had moderate adoption (36%) but usage was not sustained (4%). Closing interviews revealed that people found the filters too large and heavy, did not trust them, and found them too difficult to use. The issue of the biosand filter's size and ease of use could be partially mitigated if it were possible to reduce the height of the sand column in the filter. The filter would also be easier to use if it was not necessary to add water every day. Experiments on laboratory columns representing biosand filters determined that although the sand layer in the filters was 55 cm deep, there is little additional benefit to each centimeter over 30 cm of filter depth, making a significant height reduction possible without compromising filter performance. Further column experiments determined that the common field practice of extending residence periods of biosand filters from the recommended one day to two or three days did not lead to a statistically significant reduction in the filter's ability to remove E. coli, but did lead to anaerobic conditions within the filter and a modified nitrogen profile in filter effluent. This may impact the taste of the filtered water. In cases where influent water has high initial nitrogen content this could lead to an exceedance of World Health Organization guidelines for nitrate and nitrite in drinking water. Although the design of biosand filters was based on the theory that a low standing head would cause intermittent operation of slow sand filters to match that of continuous operation, this research found that continuous operation of the biosand filter led to significantly improved removal of bacterial and viral indicators (3.7 log10 versus 1.7 log10 for E. coli, and 2.3 log10 versus 0.9 log10 for bacteriophage MS2).Les technologies de traitement de l'eau à domicile offrent une solution temporaire pour alimenter en eau potable les zones non encore reliées à un réseau d'apport et de traitement de l'eau communautaire. C'est un problème critique pour les communautés de l'arrière-pays montagneux de la Guyane, où l'isolation géographique et la faible densité démographique rendent l'amélioration des infrastructures hydriques et sanitaires difficile. Le filtre à biosable est une technologie prometteuse pour le traitement de l'eau à domicile qui serait disponible pour pallier ces contraintes. L'objectif de cette recherche a été de mieux comprendre et d'améliorer le filtre à biosable pour son opération sur le terrain. Une étude sur le terrain, incluant la distribution des questionnaires dans la communauté et la prise d'échantillons d'eau, a été réalisée dans la communauté de St Cuthbert's en Guyane. Puiser de l'eau potable directement d'un sceau avec un récipient improvisé par opposition à avoir accès à de l'eau à partir d'un robinet s'est avéré comme étant un facteur à risque pour tomber malade. En revanche, l'accès à l'eau courante au domicile amenée par un réseau de tuyaux a été associé à des taux de maladies diarrhéiques plus faibles. La contamination de l'eau après sa collecte initiale s'est avérée comme étant un facteur causant une baisse significative de la qualité de l'eau potable. L'adoption et l'utilisation à long terme des filtres à biosable ont été comparées à celles de deux autres technologies répandues: l'ajout dans l'eau d'une solution hypochlorique combiné à l'utilisation de récipients sécuritaires d'entreposage de l'eau et la filtration à base de bougies céramiques. L'étude a montré que les filtres à biosable ont connu un taux d'adoption modéré (36%) mais que leur utilisation n'a pas été à long terme (4%). Des entrevues de fin d'étude ont indiqué que les habitants de ont trouvé les filtres à biosable larges et lourds, qu'ils ne leur ont pas fait confiance et, qu'ils ont trouvé leur utilisation difficile. Le problème des dimensions du filtre à biosable et de sa facilité d'utilisation pourrait être atténué s'il était possible de réduire la hauteur de la colonne de sable dans le filtre. Il serait aussi plus facile d'utiliser le filtre s'il n'était pas nécessaire d'y ajouter de l'eau chaque jour. Des essais en laboratoire ont déterminé que, même si la couche de sable dans le filtre a une profondeur de 55 cm, les bénéfices pour chaque centimètre additionnel de sable au-dessus de 30 cm sont minimes. Cela permettrait une réduction significative de la hauteur du filtre sans compromettre sa performance. D'autres essais ont déterminé que la pratique usuelle sur le terrain de prolonger le temps de résidence de l'eau dans les filtres à biosable, de la période recommandée d'un jour à deux ou trois jours, ne conduit pas à une diminution significative de la capacité du filtre à enlever les E. coli. Toutefois, cette pratique conduit à des conditions anaérobiques à l'intérieur du filtre et à un profil d'azote modifié dans l'effluent du filtre à cause de la nitrification. Cela pourrait avoir un impact sur le goût de l'eau filtrée. Dans les cas, où l'eau utilisée a un contenu initial d'azote élevé, les conditions anaérobiques pourraient conduire à un dépassement des recommandations de l'Organisation mondiale de la santé concernant le nitrate et le nitrite dans l'eau potable. La conception initiale des filtres à biosable a été basée sur la théorie que le maintien d'une charge hydraulique minimale permettrait aux filtres à sable lent opérant par intermittence de performer aussi bien que ceux opérant en continue. Toutefois, cette recherche a montré que l'opération continue des filtres à biosable a permis d'améliorer significativement la diminution des indicateurs bactériens et viraux (3.7 log10 versus 1.7 log10 pour E. coli, et 2.3 log10 versus 0.9 log10 pour MS2 bactériophage) par rapport aux filtres à sable lent à opération intermittente.
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Douglas, Susaye. "Post Treatment Alternatives for Stabilizing Desalinated Water." Master's thesis, University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4215.
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The use of brackish water and seawater desalination for augmenting potable water supplies has focused primarily on pre-treatment, process optimization, energy efficiency, and concentrate management. Much less has been documented regarding the impact of post-treatment requirements with respect to distribution system. The goals of this study were to review current literature on post-treatment of permeate water, use survey questionnaires to gather information on post-treatment water quality characteristics, gather operation information, review general capital and maintenance cost, and identify appropriate "lessons learned" with regards to post-treatment from water purveyors participating in the Project. A workshop was organized where experts from across the United States, Europe and the Caribbean active in brackish and seawater desalination, gathered to share technical knowledge regarding post-treatment stabilization, identify solutions for utilities experiencing problems with post-treatment, note lessons learned, and develop desalination water post-treatment guidelines. In addition, based on initial workshop discussions, the iodide content of reverse osmosis and nanofiltration permeate from two seawater desalination facilities was determined. The literature review identified that stabilization and disinfection are required desalination post-treatment processes, and typically are considerations when considering 1) blending, 2) re-mineralization, 3) disinfection, and 4) materials used for storage and transport of product water. Addition of chemicals can effectively achieve post-treatment goals although considerations relating to the quality of the chemical, dosage rates, and possible chemical reactions, such as possible formation of disinfection by-products, should be monitored and studied. The survey gathered information on brackish water and seawater desalination facilities with specific regards to their post-treatment operations. The information obtained was divided into seven sections 1) general desalination facility information, 2) plant characteristics with schematics, 3) post-treatment water quality, 4) permeate, blend, and point of entry quality, 5) post-treatment operation, 6) operation and maintenance costs, 7) and lessons learned. A major consideration obtained from the survey was that facilities should conduct post-treatment pilot studies in order to identify operational problems that may impact distributions systems prior to designing the plant. Effective design and regulation considerations will limit issues with permitting for the facility. The expert workshop identified fourteen priority issues pertaining to post-treatment. Priority issues were relating to post-treatment stabilization of permeate water, corrosion control, disinfection and the challenges relating to disinfection by-product (DBP) formation, water quality goals, blending, and the importance of informing the general public. For each priority issues guidelines/recommendations were developed for how facilities can effectively manage such issues if they arise. One of the key priorities identified in the workshop was related to blending of permeate and formation of DBPs. However, it was identified in the workshop that the impact of iodide on iodinated-DBP formation was unknown. Consequently, screening evaluations using a laboratory catalytic reduction method to determine iodide concentrations in the permeate of two of the workshop participants: Tampa Bay and Long Beach seawater desalination facilities. It was found that the permeate did contain iodide, although at levels near the detection limit of the analytical method (8 [micro]g/L).M.S.Env.E.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Environmental Engr MSEnvE
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Boucher, Alan Raymond. "Management strategies for a water treatment plant." Thesis, University of Sunderland, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292247.
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Bailey, Lucinda. "Microbial resistance to advanced water treatment processes." Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403584.
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Evans, Helen L. "Particle removal within biological water treatment filters." Thesis, University of Surrey, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298089.
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MITSUYA, RENATA TOMOE. "COOLING WATER BIOCIDAL TREATMENT USING PERACETIC ACID." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36171@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
O objetivo deste estudo foi avaliar o efeito biocida do ácido peracético (APA) em águas de sistemas de resfriamento, de forma a buscar alternativas ao uso do cloro, que é corrosivo e reage com a matéria orgânica natural ou sintética presentes na água, formando subprodutos tóxicos. Para atingir este objetivo, experimentos utilizando amostras de água retiradas da bacia de uma torre de resfriamento de uma indústria química foram realizados. Ensaios foram executados utilizando-se uma solução comercial de APA, mantendo-se concentrações do biocida em 1,0 mgL-1 e 2,0 mgL-1 em pH 8,0 e 8,8. Cada condição de estudo foi monitorada ao longo de 5 dias, e contagens de bactérias heterotróficas mesófilas totais foram realizadas tanto antes da aplicação do biocida como em diferentes tempos de contato do biocida com a microbiota natural da água. Os tempos de contato monitorados foram de 5 min, além de 1, 2 e 4 h por dia considerando a aplicação do biocida em períodos totais de 4 h por dia. Com esta metodologia foi possível concluir que as duas dosagens aplicadas foram eficientes no combate aos microrganismos presentes naturalmente nas amostras de água, nos dois valores de pH estudados. A partir de uma carga microbiana natural da água de 106 a 107 UFC/mL, após o tratamento houve uma redução para contagens de no máximo de 104 UFC/mL em todos os experimentos, limite máximo esse adotado pelas indústrias para carga microbiana em águas de sistemas de resfriamento, entretanto, houve maior eficiência, cerca de 10 vezes maior, quando 2,0 mgL-1 de APA foi aplicado. Além disso, em pH 8,0 a ação do biocida também foi superior em 10 vezes em detrimento ao pH 8,8 para a mesma concentração de APA.
The purpose of this study was to evaluate the biocidal effect of peracetic acid (PAA) in cooling water, in order to find alternatives to the use of chlorine, which is corrosive and reacts with natural and synthetic organic matter present in water, forming toxic byproducts. To achieve this goal, experiments using water samples taken from a basin of a chemical industry cooling tower were conducted. Experiments were performed using a commercial PAA solution, with concentrations of 1,0 mgL-1 and 2,0 mgL-1 and pH 8,0 and 8,8. Each study condition was monitored for 5 days and total mesophilic heterotrophic bacteria counts were made without biocide and after different contact times of the biocide and microorganisms present in water. The contact times were 5 min, and 1, 2 and 4 h per day, considering the application of the biocide in total periods of 4 h per day. This methodology has allowed concluding that two dosages applied were efficient in controlling microorganisms at the two pH values. From a water natural microbial count of 106 to 107 UFC/mL, after treatment there was a reduction to maximum counts to 104 UFC/mL in all experiments, that being the upper limit adopted by industries for microorganisms in cooling water systems. However, the results were 10 times more efficient when 2,0 mgL-1 of PAA were applied. In addition, at pH 8,0 the biocidal action was 10 times higher in comparison to pH 8,8 for the same PAA concentration.
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Akinmolayan, F. "Mathematical modelling of clean water treatment works." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1553176/.
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One of the biggest operational risks to water companies arises from their ability to control the day-to-day management of their water treatment plants. With increasing pressures to remain competitive, companies are looking for solutions to be able to make predictions on how their treatment processes can be improved. This work focuses on mathematical modelling and optimisation of clean water treatment processes. The main motivation is to provide tools which water companies can use to predict the performance of their plants to enable better control of risks and uncertainties. Most modelling work within water operations has so far been based on empirical observations rather than on mathematically describable relationships of the process as will be considered in this work. Mathematical models are essential to describe, predict and control the complicated interactions between the different parts of the treatment process, a concept which is well understood within the process industry but not yet established within the water treatment industry. This work will also consider the level of modelling detail actually required to accurately represent a water treatment plant. This thesis develops the conceptual understanding of clean water treatment processes utilising first principles modelling techniques. The main objective of this work is the consideration of a complete mathematical model of an entire water treatment plant, which enables a wider view on how changes in one processing unit will affect the treatment process as a whole. The performance of the process models are first verified individually and are then combined to enable the simulation of a complete water treatment work. By using detailed modelling (especially gPROMS utilised in this work) requires specialist software knowledge. Without knowledge of advanced simulation tools or having a background in process modelling, the detailed models developed in this work would not be fully utilised if implemented in the water industry, if utilised at all. A systematic framework is presented for the development of simpler surrogate models that can be used to predict the effluent suspended solids concentration, for a given number of independent variables. This approach can provide valuable guidance in clean water treatment process design and operation, thus providing a tool to achieve better day-to-day performance management.
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Cameli, Fabio. "Microbial Fuel Cell for Waste Water Treatment." Thesis, KTH, Skolan för kemivetenskap (CHE), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183074.
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Microbial Fuel Cell is a novel technology that can be used for a waste water treatment in order to simultaneously remove carbonaceous matter and nitrogen while producing electrical power. Even if it is not an established technology so far, MFC could be a cost effective option for waste water treatment and the major challenge of this process will be the device scale-up. Exoelectrogenic bacteria are capable of converting the chemical energy of organic matter into electrical energy by transferring the electrons produced in the oxidation to the anode electrode. This project focused on developing a single device for nitrification, denitrification and carbon removal. Two double air-cathode single chamber MFCs are used to test the feasibility of this process that could replace the biological unit in a waste water treatment train. The cells tested in this study were manufactured with the purpose of achieving a high surface area on both the anode electrode (vitreous carbon foam) and the air-cathode electrodes (metallic mesh with diffusion layer and active layer) with different catalysts for the reduction reaction (cobalt and platinum). The bacterial biofilm growth is a fundamental step and the cells Open Circuit Potential was monitored during all the start-up period to determine the microorganism acclimation: a three days lag period was observed in both cells before the potential rise. The second cell was forced to reach higher voltage through an anode polarization and that seems to positively affect the biofilm stability at lower voltages transferring a greater amount of electrons and hence obtaining a higher current and power generation. For this reason after three weeks of inoculation the second cell reached an open circuit potential of 0.76 V which is a promising value for such a system. Electrochemical and biological tests were conduced in order to test the power production of the cell and the substrate removal from the waste water. Polarization curves were used to evaluate power generation (and the maximum production under a specific external load) and the cell voltage trend which is characterized by activation and ohmic losses: 32 mW/ and 41 mW/ are the power density normalized by cathode surface (72 ) reached by respectively first and second cell. The experimental conditions were varied from low to high temperature and from low to high inlet flow rate but the most affecting phenomenon seems to be the biofilm formation since significant voltage drops were noticed after long closed circuit operation. Higher cell voltage characterized the second cell thanks to more active cathode (platinum catalyst used) and more negative bacterial biofilm but a bigger drop in current generation over time affects the system performance and the most reliable reason is the shorter acclimation time compared to the first cell. Cyclic voltammetry tests were carried out on both electrodes to study the potential range of activity and determine an optimal operational voltage despite of mass transport or kinetic limitations. Substrate removal tests at different retention times in power generation conditions (external load 100 Ω) showed a relatively high total nitrogen consumption (maximum 72.2 %) for the first cell while lower values were achieved by the second system meaning that a longer acclimation period is beneficial for nitrifying and denitrifying bacteria to thrive on the cathode biofilm. Effluent pH level are almost similar to the initial values probably because of nitrification and denitrification protons offset.
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Hung, Isaac, and Isaac Hung. "Ultrafine Bubble-Enhanced Ozonation For Water Treatment." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/621853.
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Ultrafine bubbles, often referred to as nanobubbles, have been used in various applications from environmental remediation to medicine. Even though the technology to generate ultrafine bubbles has been around for many years, the full potential of its applications has not been completely studied. This project seeks to study the use of ultrafine bubble technology for water treatment in combination with ozone gas. A factorial design experiment was chosen to test the effects of ultrafine bubbles on the concentration of an indicator organism, E. coli, in water as well as their effects on ozone gas being injected into water. Ozone gas or nitrogen gas was injected into water contaminated with E. coli as either ultrafine bubbles or fine bubbles as treatments for up to 60 minutes. Ultrafine bubbles were found to not have any significant effect on the concentration of E. coli in water. However, ultrafine bubbles did provide benefits when used in conjunction with ozone gas that regular, fine bubbles did not provide. The benefits included allowing the concentration of dissolved ozone in the water to decrease at a slower rate as well as allowing more ozone to dissolve into water at a higher rate than conventional methods of bubbling in ozone. While in this particular set of experiments the concentration of dissolved ozone in water didn't surpass 2 mg/L, which didn't allow for rapid disinfection and treatment of water, it is believed that with a more powerful ozone generator better results can be achieved. This project demonstrates the benefits and potential of injecting ozone gas as ultrafine bubbles into water as a way to effectively and efficiently disinfect and treat water.
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Kadhim, Mohammed Salman. "Characterisation of nanoporous polymers for water treatment." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/4011.
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Materials which have structural dimensions between 1 nm and 100 nm are called nanomaterials. These materials have unique geometric, physicochemical and mechanical properties. As a result of their properties, nanomaterials can be tailored for specific applications. Polymers Synthesized from High Internal Phase Emulsions (PolyHIPEs) are a type of porous material with high specific surface area due to their nanoscale structure which have the ability to function as ion exchange media that can remove contaminants from water. PolyHIPEs can therefore be used in ion exchange modules to remove metals from wastewater. The advantage of using PolyHIPEs is that fewer steps are necessary compared with traditional filtration methods, and they are more economic and more selective than the traditional materials. A high internal-phase emulsion (HIPE) contains both oil and aqueous or dispersed phases. The oil phase has monomers such as styrene, a cross-linker such as Divinylbenzene (DVB), and non-ionic surfactants while the aqueous phase consists of deionized water and polymerisation initiators such as potassium pyrosulphate. The emulsion is subjected to the polymerization process, usually at 60 ̊C and pores are produced within the polymer due to the presence of the aqueous phase. The polyHIPE is then washed with propanol to release the residual surfactant and unreacted monomer. In this work, we used different HIPE mixing times (10, 15, 20, 25, and 30 minutes, respectively) in order to change the pore size distribution. After synthesis the PolyHIPEs are subjected to a sulphonation process which changes the PolyHIPE character from hydrophobic to hydrophilic. Finally, ion exchange experiments have been conducted by using sulphonated PolyHIPE beads as is and coated with iron oxide. As simulated contaminated water nickel and copper solutions were used during this process. The results show the removal efficiency of the metal ion from solution was much higher with sulphonated beads at range of pH (6, 7, 8 and 9). Changing the pH allowed the metals to be removed from the PolyHIPE for recovery and filter regeneration but the amount of metals after the regeneration process is low compared with initial concentration.
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See, Hwee J. "Optimisation of water and wastewater treatment processes." Thesis, University of Cambridge, 2002. https://www.repository.cam.ac.uk/handle/1810/272064.
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Gunukula, Sampath Reddy. "ELECTROCOAGULATION/FLOTATION TREATMENT OF SYNTHETIC SURFACE WATER." Cleveland State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=csu1304363574.
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Arnette, Verna J. "Cyanotoxin Removal in Drinking Water Treatment Processes." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1258475751.
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Zhu, Yan, Chao Zhang, Xiaolong Shen, and Micah Kneeshaw. "Waste Water Treatment on a Naval Ship." Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/145127.
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Billings, Shasta Le'ja. "Cloth Filter for Disaster Relief Water Treatment." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/919.
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Relief organizations and governments strive to provide safe drinking water to natural disaster survivors as quickly as possible. However, drinking water is typically provided either as bottled water or via mobile water treatment equipment, both of which can be difficult or expensive to transport rapidly into disaster zones. An alternative is the waterbag point-of-use treatment device developed at Cal Poly that allows survivors to produce safe drinking water from contaminated local sources. The waterbag is a 10-L bladder designed for use with Procter & Gamble Purifier of Water (PŪR®) sachets, which contain coagulant and chlorine compounds. Following treatment with PŪR®, treated water in the waterbag is flowed through an outlet port to a filter, primarily for parasitic cyst removal. Currently, the commercial version of the waterbag uses an effective but expensive hollow-fiber membrane microfilter (>$10 each). This cost will likely decrease the use of the waterbag by relief organizations responding to large disasters. The goal of the present thesis research was to develop a novel, low cost (~$5), effective, low-profile filter to be used with the waterbag in large-scale disaster relief. This new filter is referred to as an envelope filter due to its geometry and size.
Various prototype envelope filters were constructed using layers of nonwoven polypropylene filter cloth. Two types of cloth were used: a nominally-rated 1-µm pore size cloth and an absolute-rated 1-µm cloth. The filters tested were both internal and external to the waterbag and of various geometries. Filters were attached to the waterbag and used to filter defined test water after it had been treated with a PŪR® sachet. Test water for design experiments consisted of tap water with addition of standard dust (to increase turbidity) and seasalts (to increase salinity). In addition to this basic test water, mock U.S. EPA Challenge Water #2 with added bacteria and cyst surrogates (fluorescent microspheres) was used to evaluate the filter prototype designs prior to testing according to U.S. EPA Guide Standard and Protocol for Testing Microbiological Water Purifiers in a commercial laboratory.
The filter design and mock challenge experiment results indicated that a 2-ply filter with one nominal and one absolute layer was the optimal filter design. In the mock U.S. EPA challenge tests, a flowrate of 20 mL/min allowed this filter met the turbidity, bacteria, and microsphere removal requirements determined by the WHO and The Sphere Project for emergency drinking water treatment as well as the U.S. EPA Guide Standard and Protocol for Testing Microbiological Water Purifiers.. This filter design was further tested using the U.S. EPA Challenge Water #2 with triplicate waterbags at the U.S. EPA-certified BioVir Laboratories in Benicia, Calif. All three waterbags with envelope filters met the recommendations for turbidity (<5 >NTU) and for virus removal (>4-log removal). Two of the three waterbags met the bacteria and microsphere removal requirements (>6- and >3-log removal, respectively). The failure of one of the prototypes to meet the requirements could have been due to improper setting of valve that throttled the flowrate through the filter or due to a slightly leaking hose pinch valve. Future work should include incorporating more reliable valves and improving the envelope filter design and materials to achieve higher allowable flowrates.
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Gang, Dianchen. "Modeling of THM and HAA formation in Missouri waters upon chlorination /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3025619.
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Delgado, Guillermo Guadalupe. "Treatment of RO concentrate using VSEP technology." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Toll, Nils. "Considerations and Novel Technologies in Industrial Water Treatment - Treatment of challenging wastewater." Thesis, KTH, Kemiteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297642.
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Industriell vattenrening är ett extremt viktigt område inom Miljöskyddsteknik då 60% av allt sötvatten inom Sverige används av industrier. Substanser som PFAS, aromatiska textilfärger, fenol och läkemedelsrester är extra utmanande då dessa kan vara gifta för biologisk rening. Syftet med denna rapport var att först redogöra några av de viktigaste avvägningarna som behöver göras när ett industriellt vattenreningsverk designas. I del två av arbetet har en kartläggning av teknologier som kan användas för att assistera eller ersätta biologisk rening. Det existerar flera olika typer av tekniker för att ersätta biologisk rening, men majoriteten av dessa konsumerar stora mängder värme eller elektricitet, vilket kan leda till stora rörliga kostnader. En trend inom industriell vattenrening är elektrifiering. Elektrifiering ger möjlighet att återvinna kemikalier, selektiv separation av joner, automatisk justering av pH via tekniker som elektrodialys och elektrokoagulering. Kall plasmaoxidation och kavitation kan även användas för destruktion av organiska ämnen. I takt med att förnyelsebar energi blir billigare att producera och om regeringen inför el-subventioner för industrin så kommer användbarheten av dessa tekniker att öka. Membranprocesser kan användas för att intensifiera processer som extraktion och indunstning. Med hjälp av membran kan separationshastigheten och energianvändningen minskas. Enzym kan användas för att skräddarsy rening för att bryta ner specifika ämnen vid låga tryck och temperaturer. Skumseparation är en mycket lovande process som kan användas för separation av ytaktiva ämnen som PFAS och har en mycket enkel design och låga energikostnader.Industrial water treatment is an important field of study as industries in Sweden consumes over 60% of the available freshwater. Furthermore, only 60% of the industrial wastewater in Europe receive treatment before its discharged. Hard to oxidize compounds such as dyes, phenol, and PFAS are a major problem within the field as they often exhibit toxic or inhibiting qualities towards biological treatment methods. Therefore, the purpose of this thesis is twofold; firstly, some of the most important considerations when designing an industrial wastewater treatment plant is discussed to aid someone new to the field. Secondly, novel technologies that could be used to support or replace biological treatment methods are discussed. There exist several different novel technologies that can be used to treat organic pollutants. However, many of these techniques are very energy intensive, leading to high operational costs. A major trend within wastewater treatment is the electrification of treatment techniques. These enables the recycling of chemicals, selective removal of ions and automatic neutralization of pH by means of electrodialysis and electrocoagulation. They can also be used for destruction of organics using cavitation or cold plasma oxidation. The usefulness of these techniques is likely to increase in the future as the electrification of industry picks up speed and subsidies on industrial electricity prices are put in place. Membrane processes can intensify already existing unit operations such as evaporation and extraction. By employing a membrane, the speed of separation and the energy use can be lowered. Enzymatic treatment can be used to degrade several different compounds at low temperatures and pressures by tailoring the mix of enzymes to perfectly fit the wastewater in question. Foam separation is also interesting technology in the removal of surface-active chemicals and compounds due to its simplistic design and low operational cost. The use of this technology is likely to increase in the future if the legislation regarding persistent organics is tightened further.
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Hassinger, Elaine, and Jack Watson. "Mound Systems: Alternative On-site Wastewater Treatment." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 1998. http://hdl.handle.net/10150/146416.
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2 pp.The conventional on-site household wastewater treatment system is known as the septic tank and absorption (leach) field. Local soil conditions; type, depth, texture and permeability all contribute to how well wastewater is treated as it moves toward groundwater. Soil conditions in parts of Arizona are not suitable for absorption fields, so alternative disposal systems are necessary. This article provides information on alternative disposal systems, the septic tank-mound system, and includes the description of the system, its background, where it should be used, and the cost and time consideration.