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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Enhancement of the Mesophilic Anaerobic Co-digestion of Municipal Sewage and Scum

Young, Bradley 23 November 2012 (has links)
Scum is an integral component of solids management in MWWTP and is composed of fats, oils, grease and other entrained floatable materials that are collected during primary clarification. Lab scale BMP tests showed the addition of 14.5 g VS/L of scum exhibited the greatest increase in biogas production of 1.6 times per g VS added compared to the control, while a higher additional scum loading of 33.7 g VS/L reduced the biogas yield to 32% of the control reactor. Lab scale semi-continuous digestion measured the effects of scum loading and temperature of pretreatment in the scum concentrator. At 15 d and 20 d HRTs the greatest observed improvement in biogas was achieved by adding 3% scum by volume and pretreating the scum at 70°C in a scum concentrator with respective improvements of 24% and 16%.
12

Fate of perfluoroalkyl acids in the aquatic environment with a focus on mass balance studies

Filipovic, Marko January 2015 (has links)
Perfluoroalkyl substances (PFASs) are man-made chemicals. Their unique properties make them beneficial for a wide range of industrial and consumer product applications, such as in aqueous film forming foam (AFFF), durable water repellent clothing, hydraulic oils and food packaging materials. Perfluoroalkyl acids (PFAAs), a class of PFASs, are highly persistent in the environment, and long chain PFAAs are bioaccumulative and toxic. International regulation and voluntary actions by the industry have been implemented and led to a recent reduction of primary emissions of PFAAs to the environment. However, point sources such as AFFF training sites as well as diffuse sources continue to contaminate water bodies, soil and biota. Reducing environmental pollution with PFAAs has therefore become a regulatory priority. Designing successful measures to reduce the PFAA contamination requires an understanding of the sources, transport and fate of PFAAs in the environment. Four scientific publications are included in this PhD thesis, which aimed at increasing the holistic understanding of the fate of PFAAs in aquatic systems. This was achieved by chemical trace analysis combined with mass balance modeling. The following topics were covered: Dispersion and fate of PFAAs from an AFFF-impacted site (Paper I), recirculation of PFAAs in the aquatic environment with focus on waste water treatment plants (WWTPs, Paper II), mass balance of PFAAs in the Baltic Sea (Paper III) and transport and fate of PFAAs in two pristine boreal stream catchments (Paper IV). Results from Paper I showed that AFFF-impacted sites at a former military airfield, which was abandoned for more than 30 years, continue to be point sources of PFAAs to recipients. The sum of PFAAs in the ground water and surface waters ranged from 740 to 51000 ng L-1 and &lt;0.5 to 79 ng L-1, respectively. PFOS in muscle tissue of European perch from a nearby lake ranged from 77 to 370 ng g-1 wet weight, representing among the highest values reported worldwide for fish muscle. In Paper II the relative importance of environmental recirculation of PFAAs versus new releases from the technosphere was investigated for PFAAs in WWTP influents. It was shown that tap water can be an important source of PFAAs to WWTPs in areas with elevated environmental levels. This needs to be taken into account when calculating emissions via WWTP effluents. PFAA mass balances over the WWTPs suggested that PFHxA and PFOA were formed from precursor compounds within the plants. Assembled PFAA mass balances for the Baltic Sea (Paper III) showed that river inflow and atmospheric deposition were the dominant input pathways, while wastewater treatment plant (WWTP) effluents discharging directly into the Baltic Sea made a minor contribution. The inputs of PFAAs were estimated to be higher than the outputs, suggesting a current increase of the PFAA inventory in the Baltic Sea. Also the mass balance study of PFAAs in two remote stream catchments presented in Paper IV revealed that inputs dominated over outputs for both catchments, indicating that a considerable portion of the PFAAs deposited from the atmosphere is retained in soil or in deep ground water and may be released to surface and marine water environments in the future / Perfluoralkilne tvari (PFASs) su umjetne kemikalije. Zbog svojih jedinstvenih svojstava široko su primjenjive u industriji i izradi proizvoda krajnje potrošnje kao što su pjena za gašenje požara (AFFF), vodootporna odjeća, hidraulična ulja i pakiranja za hranu. Perfluoralkilna kiselina (PFAAs) iz skupine perfluoralkilnih tvari iznimno je dugotrajna u okolišu, a dugolančane PFAAs su bioakumulativne i otrovne. Poduzeta međunarodna regulativa i dobrovoljne akcije vodile su nedavno smanjenoj primarnoj emisiji PFAAs u okoliš. Unatoč tome, primarni izvori, kao što su mjesta na kojima se provode treninzi za gašenje požara i difuzni izvori i dalje zagađuju vode, tlo i biotu. Zbog toga, smanjenje onečišćenja okoliša izazvanog PFAAs predstavlja regulatorni prioritet. Stvaranje uspješnih mjera kojima bi se smanjilo onečišćenje izazvano PFAAs zahtjeva razumijevanje izvora, prijenosa i sudbine tih tvari u okolišu. U ovaj doktorat uključena su četiri znanstvena članka kojima je cilj povećati sveukupno razumijevanje sudbine PFAAs u vodenim sustavima. To je postignuto kemijskom analizom elemenata u tragovima u kombinaciji s modeliranjem masene ravnoteže. Obrađene su sljedeće teme: Širenje i sudbina PFAAs na područjima zahvaćenim AFFF (Članak I), ponovna cirkulacija PFAAs u vodenom okolišu s naglaskom na postrojenja za pročišćavanje otpadnih voda (Članak II), masena ravnoteža PFAAs u Baltičkom moru (Članak III) te prijenos i sudbina PFAAs u dva udaljena sjeverna vodena toka (Članak IV).   Rezultati iz Članka I pokazali su da su područja zahvaćena AFFF na bivšem vojnom aerodromu napuštenom prije 30 godina i dalje je glavni izvor PFAA zagadenja okolisa. Zbroj PFAAs u podzemnim i površinskim vodama kreće se u rasponu od 740 do 51000 ng L-1 i &lt;0.5 do 79 ng L-1. PFOS u mišićnom tkivu grgeča iz obližnjeg jezera kreće se od 77 do 370 ng g-1 mokre težine, predstavljajući jednu od najviših vrijednosti u svijetu za riblje mišiće. Članak II istražuje relativnu važnost ponovne cirkulacije PFAAs imajući na umu novu emisiju PFAAs iz tehnosfere u postrojenjima za pročišćavanje otpadnih voda. Cirkulacija/kruženje u okolišu može se pojaviti kada PFAAs iz sustava pitke voda (rijeka, bunara i jezera) odlaze u otpadne vode. Prikazano je kako voda iz slavine može biti važan izvor PFAAs sustavima za pročišćavanje otpadnih voda u područjima s povišenim razinama zaštite okoliša. To se treba uzeti u obzir pri računanju emisije putem strojeva koji se koriste za pročišćenje otpadnih voda. Masena ravnoteža PFAA u postrojenjima za pročišćavanje otpadnih voda upućuje na to da su PFHxA i PFOA stvoreni kao prethodni spojevi unutar postrojenja. Prikupljene masene ravnoteže PFAA za Baltičko more (Članak III) pokazale su da su pritoke rijeka i atmosfersko taloženje dominantni ulazni putovi, dok postrojenja za pročišćenje otpadnih voda pridonose tek u manjoj mjeri. Ulaz PFAAs je procijenjen višim od izlaza, što objašnjava trenutno povećanje sadržaja PFAA u Baltičkom moru. Masena ravnoteža PFAAs u dva udaljena riječna toka predstavljena u Članku IV otkriva da ulaz dominira nad izlazom za oba riječna toka, što upućuje na značajan udio PFAAs koji je iz atmosfere zadržan u tlu ili podzemnim vodama te može biti ispušten u područja površinskih voda i mora. / Perfluorerade alkylsyror (PFAA) är kemikalier som är producerade av människan. Deras unika egenskaper gör att de kan användas i många olika industriella applikationer. PFAAs används i brandsläckningsskum, vattenavvisande kläder, hydrauliska oljor och matförpackningar. PFAAs har visat sig vara persistenta i miljön, och långkedjiga PFAA-homologer har visat sig vara bioackumulerbara samt ha en toxisk verkan. Reglering på internationell nivå tillsammans med initiativ från industrin har lett till minskning av direkta utsläpp. Punktkällor som brandövningsplatser samt andra diffusa källor fortsätter att förorena omgivande vattendrag, jordlager och fauna. Den utbredda föroreningen av PFAAs har därför blivit prioriterad för reglering. För att förstå utsläppen av PFAAs i miljön, hur de transporteras samt deras öde i miljön, är det viktigt att utföra studier som belyser dessa områden.   Denna doktorsavhandling inkluderar fyra vetenskapliga publikationer. Syftet med de underliggande studierna var att öka den holistiska förståelsen av PFAAs rörelse i akvatiska system. Studierna gjordes genom att kombinera kemiska analysmetoder med modellering. Följande  studier genomfördes; Transport och spridning av PFAAs från en brandövningsplats (Paper I), recyklering av PFAAs i den akvatiska miljön med fokus på vattenreningsverk (Paper II), massbalans av PFAAs i Östersjön (Paper III), transport och öde av PFAAs i två pristina vattendrag (Paper IV).   Resultat från (Paper I) visade att brandövningsplatser vid en flygplats som inte har varit i bruk i mer än 30 år, fortfarande är punktkällor av PFAAs till omgivande vattendrag. Summan av PFAAs koncentrationer i grundvattnet och ytvattnet sträckte sig från 740 till 51000 ng L-1 och &lt;0.5 till 79 ng L-1 i respektive vattendrag. Koncentrationen av PFOS i muskelvävnad från  aborre i en av sjöarna var 77 till 370 ng g-1 våtvikt. Dessa värden representerar några av de högsta uppmätta koncentrationerna i världen. I Paper II testades betydelsen av PFAAs från recirkulering i miljön i jämförelse med nya utsläpp från teknosfären. Recirkulering av PFAAs i miljön kan förekomma då PFAAs i inkommande vatten till reningsverk kommer från dricksvatten. Denna studie visar att dricksvatten kan vara en påtaglig källa av PFAAs till vattenreningsverk i områden med förhöjda halter av PFAAs i miljön. Detta måste tas hänsyn till när man beräknar emissioner med utgående vatten från vattenreningsverk. Massbalanser av PFAAs i reningsverken visar att PFHxA och PFOA bildades av prekursorämnen i vattenreningsverken. I Paper III beräknades massbalanserna av PFAAs i Östersjön, beräkningarna visar att floder och atmosfärisk nedebörd var de viktigaste källorna medan utsläppen från vattenreningsverk var markant lägre. Importen av PFAAs estimerades vara högre än exporten, varför vi tror att PFAAs mängden I Östersjön kommer att öka över tid. Vidare gjordes en mass balans av PFAAs i två avlägsna avrinningsområden (Paper IV). Resultaten visar att importen av PFAAs dominerar över exporten från båda avrinningsområdena. Detta indikerar att en stor del av PFAAs som kommer ner via nederbörd kommer att ansamlas i jorden eller i grundvattnet. Dessa PFAAs kan vid senare tillfälle komma att släppas ut till floder som rinner ut i marina vatten. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.</p><p> </p>
13

Contribution of polyfluoroalkyl phosphate esters (PAPs) and other precursor compounds to perfluoroalkyl carboxylates (PFCAs) in humans and the environment

Eriksson, Ulrika January 2016 (has links)
Per-and polyfluoroalkyl substances (PFAS) are anthropogenic compounds that have been spread all over the world. The use of fluorotelomer compounds, short-chained homologues, and other PFASs with perfluorinated moieties has emerged recent years. One of these emerging compound classes is polyfluoroalkyl phosphate esters (PAPs), which have the ability to degrade into persistent PFCAs. The aim of this thesis was to assess the contribution of PAPs and other precursors to the exposure of PFCAs to humans and the environment. The main objective was to analyze a wide range of PFAS in human serum, wild bird eggs, indoor dust, waste water, and sludge. There was a significant contribution from selected precursors to the total amount of PFASs in the abiotic compartments indoor dust, waste water, and sludge. Levels of PAPs found in house dust exceeded those of PFCAs and perfluorosulfonic acids (PFSAs), revealing PAPs as a world-wide important exposure source. A net increase was during waste water treatment was observed for several PFASs in Swedish waste water treatment plants. Together with presence of precursor compounds and intermediates in the influent water and the sludge, this suggest that degradation of PFCA precursors contributed to the increase of PFCAs. Detection of precursors in human serum, together with slow declining trends of PFCAs, revealed an ongoing exposure of PFCAs to the general population of Australia. The diPAPs and the FTSAs were also detected in raptor bird eggs from Sweden from both the terrestrial and the freshwater environment. The precursors concentrations and patterns observed reveal that current regulatory measures are insufficient for the purpose of protecting humans and the environment from PFASs exposure.
14

First assessement of sources and fate of macro and micro plastics in urban hydrosystems : Case of Paris megacity / Premières investigation des sources et devenirs des macro et micro plastiques dans les hydrosystèmes urbains : cas de agglomération parisienne

Dris, Rachid 09 December 2016 (has links)
Le risque environnemental lié à la présence de plastiques dans les milieux aquatiques a été suggéré, pour le milieu marin, dès les années 1970. Même s’il reste incomplètement cerné (d’un point de vue écotoxicologique essentiellement), il ressort de la littérature qu’il est significatif. Même si certains travaux suggèrent qu’une grande partie de ces plastiques provient des eaux continentales, il n’existe aujourd’hui peu d’étude sur les niveaux d’imprégnation des milieux aquatiques en milieu continental et aucune à l’échelle des bassins versants urbains pour préciser l’importance des différentes sources urbaines.Dans cette étude, les macroplastiques (> 5 mm) ainsi que les microplastiques (<5 mm) sont considérés. Les flux de macroplastiques dans la Seine ont été estimés à l’aide d’une étude de terrain mais aussi à l’aide d’une approche théorique. En ce qui concerne les microplastics, les fibres (synthétiques et artificielles) ainsi que les fragments ont été étudiés dans différent compartiments du système urbain. L’air intérieur, les retombées atmosphériques, les eaux de ruissellement, les effluents et affluents de stations d’épuration ainsi que les rejets urbains en temps de pluie ont été étudiés.Les concentrations en microplastiques dans le milieu récepteur ont aussi été estimées. Le suivi de la contamination des eaux de surface a été abordé selon deux méthodes d’échantillonnage distinctes : échantillonnage par un filet avec une maille de 80 μm et par un filet de 330 µm. L’homogénéité des fibres le long de la section a aussi été estimée, tout comme la variabilité temporelle à court terme. Pour finir, un suivi mensuel sur 19 mois a été effectué en amont et en aval de Paris.Cette étude a permis de montrer que les flux de microplastiques dans la Seine représentent une masse négligeable par rapport aux flux de macroplastiques. Elle confirme aussi l’ubiquité des fibres dans tous les compartiments. Les fragments sont quant à eux particulièrement concentrés dans les rejets urbains en temps de pluie. Pour la première fois, il a été montré que le compartiment atmosphérique jouait un rôle potentiellement important, autant que source de microplastiques / Plastic pollution has been widely studied in marine environment since 1972 and mostly since 2004. Investigations on plastic pollution in freshwater and especially in urban catchments just started at the beginning of the decade, and urban plastic pollution sources and its related fluxes in rivers remains mainly unknown. Thus a specific attention should be paid to the plastic contamination in catchments exposed to severe anthropogenic pressure, especially within the urban areas. This PhD thesis focuses on the case of the Paris agglomeration and its impact on the Seine River. A double approach was carried out as both macro- (>5mm) and micro- (<5mm) plastics were considered.The amount of macroplastics conveyed by the Seine River was estimated with a field study and with a theoretical approach.Regarding microplastics, fibers (made with synthetic but also man-made polymers) and fragments were both investigated in different compartments of the urban system. The study focused on the air compartment (indoor and outdoor air as well as atmospheric fallout), the sewer system (from the washing machine disposals to the WWTP influents and effluents), and the inputs during wet weathers periods, i.e, runoff and combined sewer overflows. Fibers and fragments were also examined on the Seine River.This work aimed at providing relevant methodological keys to address sampling of microplastic in rivers. Two mesh size nets were tested (80 µm vs. 300 µm). The homogeneity of fibers distribution in rivers was also verified as the short term temporal and spatial variabilities were evaluated. In order to highlight the potential impact of the Paris agglomeration, a monthly monitoring on 5 sites upstream and downstream Paris was carried out as well.This thesis mainly highlighted the ubiquity of fibers in all compartments. Fibers were predominant in comparison to fragments in all compartments. Combined sewer overflows exhibited particularly high amounts of fragments. On the other hand, the flux of microplastics in the Seine River was proved be negligible in terms of mass in comparison to macroplastics. This study is also the first one showing that the atmospheric compartment needs to be considered as a potential significant source of microplastics
15

Enhancement of the Mesophilic Anaerobic Co-digestion of Municipal Sewage and Scum

Young, Bradley January 2012 (has links)
Scum is an integral component of solids management in MWWTP and is composed of fats, oils, grease and other entrained floatable materials that are collected during primary clarification. Lab scale BMP tests showed the addition of 14.5 g VS/L of scum exhibited the greatest increase in biogas production of 1.6 times per g VS added compared to the control, while a higher additional scum loading of 33.7 g VS/L reduced the biogas yield to 32% of the control reactor. Lab scale semi-continuous digestion measured the effects of scum loading and temperature of pretreatment in the scum concentrator. At 15 d and 20 d HRTs the greatest observed improvement in biogas was achieved by adding 3% scum by volume and pretreating the scum at 70°C in a scum concentrator with respective improvements of 24% and 16%.
16

Treatment of per- and polyfluoroalkylsubstance (PFAS)-contaminated waterusing aeration foam collection

Kjellgren, Ylva January 2020 (has links)
Landfills are potential sources for PFASs and treatment techniques for landfill leachate are urgently needed. Foam fractionation is an aeration technique which utilizes the tendency of PFASs to escape the liquid phase and build foam. The foam is harvested and with it the contamination. Landfill leachate from Hovgården, Uppsala Sweden contained PFASs of higher concentration than desired and investigations into whether foam fractionation could reduce PFASs amounts were initiated. Landfill leachate containing sum PFASs of 5500 ng/L on average were aerated in two different aeration foam collection pilot set-ups for the research. The pilot set-ups were divided into two models: a batch pilot and a continuous pilot. The batch pilot was run for 60 minutes testing parameters such as column volume, air flow rate, dilution and using additives as NaCl, FeCl3 and dish soap. The continuous pilot used contact times of 5, 10 and 20 minutes with constant air flow rate and column volume and no additives. All batch experiments showed reduced concentrations of PFASs, from 62 up to 91%, with an average sum PFASs removal efficiency of 77%. Air flow rates of 4 and 6 L/min were more effective than 2 L/min to reduce the amount of PFASs. Smaller volumes got higher removal efficiency. The dilution experiments showed mixed and somewhat contradictory results, where the nondiluted experiment had removal efficiency of sum PFASs of average 77% while the 50% diluted had an average sum PFASs removal efficiency of 84%. The experiment with the greatest dilution (75%) had the lowest average sum PFASs removal efficiency as suspected, at 68%. Regarding additives, the experiments with added 0.155 and 0.313% NaCl in the leachate were most effective at removing PFASs. The dish soap and FeCl3 additives also contributed to higher PFASs reduction. The experiment with the addition of dish soap had an average sum PFASs removal efficiency of 88% compared to 77% without additives, and the highest concentration of FeCl3 (0,09% of the leachate) had an average sum PFASs removal efficiency of 85%. All continuous experiments showed reduced reduced PFASs concentrations with sum PFASs removal efficiencies ranging from 72 up to 94%, with an average of 86%. The majority of the PFASs were reduced within the first time steps for all experiments, but for the last amount to be removed the contact time needed to be longer. The column contact time of 20 min had the highest average sum PFASs removal efficiency. The conclusion is that PFASs are reduced during the treatment in the pilots and that the reduction is dependent on the chain length and functional groups of the substances, and increased with additives and increased air flow rate. The volume treated and the concentration of raw water also influenced the removal efficiency.
17

Získání a opětovné využití celulózy z odpadní vody / Harvesting and reuse of cellulose from wastewater

Kobzová, Kamila January 2019 (has links)
The goal of this diploma thesis is to highlight the properties of cellulose fibers obtained from waste water and the importance of recycling of raw materials. The main objective is then to further explore the possibilities of using cellulose fibers as a valuable product on the market. The practical part of the thesis is focused on specific research of cellulose properties and design of equipment for sewage treatment plant according to its size.
18

Optimalizace energetických toků při provozu ČOV - Smart Area Net / Optimization of Energy Flow During WWTP Operation - Smart Area Net

Pěcha, Jiří January 2021 (has links)
The dissertation work deals with the issue of water treatment and possibilities of energy savings during the operation of sewage treatment plants. The aim of the work is to find the potential of alternative energy use, economical consumption, improvement of the facility system management and quality improvement of the wastewater treatment process. In the first part of the work, operating processes, energy flows and energy savings are discussed. To analyze the problematics, larger sewage treatment plants were chosen. Thanks to their size, it was easier to find critical points and test the usage of renewable sources in operation. After the energy audit, the individual processes were assessed and real operation pitfalls were determined. Further steps led to focusing on smaller facilities up to 2 000 PE. This step was carried out with the intention of preparing these plants for the planned legislative change and helping to create or modernize more energy-efficient solutions. Thanks to the establishment of consortium of Brno University of Technology, the Department of Electric Power Engineering and a company dealing with water treatment and automation control, a solution was created that modernize the electrical, automation and water treatment part of the plant operation. This innovative application was installed in the sewage treatment plant, where the issues were debugged, control algorithms were tested and the entire operation was launched in automatic mode. At the end of the wastewater treatment plant modernization, PV panels were installed on the roof, thus partially suppling the object with renewable energy.
19

Využití separačních metod pro stanovení vybraných léčiv ve vodách / Application of separation methods for the determination of selected pharmaceuticals in waters

Burešová, Jitka January 2008 (has links)
Antibiotics are widely used pharmaceuticals in human and veterinary medicine. These compounds are biologically active. They decrease efficiency of biological processes in wastewater treatment plants. Antibiotics are not eliminated from sewage water completely and they are discharged as contaminants into the receiving waters. Several methods exist for the determination of antibiotics in sewage water. In the first place liquid chromatography, gas chromatography and capillary electrophoresis are used. The aim of this thesis was to developed a suitable izolation technique and an optimal analytical method for identification and determination of penicillins in wastewater. For determination was selected amoxicillin, ampicillin and benzylpenicillin (penicillin G). These are very often used penicillins. An optimized method was used for determination of these penicilins in real samples from a wastewater treatment plant situated in Veterinary and pharmaceutical university in Brno and from the large-scale wastewater treatment plant in Brno-Modřice. Real samples were concentrated using SPE (solid phase extraction). For penicillins determination were used high performance liquid chromatography with diode array detection (HPLC/DAD).
20

STUDY ON TREATMENT TECHNOLOGIES FOR PERFLUOROCHEMICALS IN WASTEWATER / 下水中のペルフルオロ化合物の処理技術に関する研究 / ゲスイチュウ ノ ペルフルオロ カゴウブツ ノ ショリ ギジュツ ニ カンスル ケンキュウ

Qiu, Yong 23 July 2007 (has links)
学位授与年月日: 2007-07-23 ; 学位の種類: 新制・課程博士 ; 学位記番号: 工博第2837号 / Perfluorochemicals (PFCs) were produced by industries and consumed “safely” as surfactants, repellents, additives, fire-fighting foams, polymer emulsifiers and insecticides for almost fifty years. However they are now considered as persistent, bioaccumulated and toxic (PBT) chemicals, and ubiquitously distributed in waster, air, human body and biota. Although some efforts were contributed to reduce PFCs in environment, such as development of alternatives and recycling processes, huge amount of persisted PFCs have already been discharged in environment and accumulated in biota including humans. In some industrialized areas, such as Yodo river basin in Japan, water environment and human blood were polluted by some PFCs, and thus reduction and control of PFCs were urgently required for the purpose of environmental safety and human health in these areas. Unfortunately, some studies implied that current water and wastewater treatment processes seemed ineffective to remove PFCs in trace levels. Therefore, this study will try to develop some proper technologies to treat trace level of PFCs in wastewater. In order to achieve this main objective, several works have been accomplished as follows.  Current available literature has been reviewed to obtain a solid background for this study. Basic information of PFCs was summarized in physiochemical properties, PBT properties, productions and applications, regulations and etc.. Analytical methods for PFCs, especially of LC-ESI-MS/MS, were reviewed including pretreatment processes in diverse matrices, which derived objectives of chapter III. Distributions and behavior of PFCs were briefly discussed in water environments, biota sphere and human bloods. Available control strategies were shown in detail about alternatives, industrial recycling processes, and newly developed treatment processes. Current wastewater treatment processes showed inefficient removal for some PFCs, deriving objectives of chapter IV on the PFC behavior in treatment process. Newly developed treatment technologies seemed able to decompose PFCs completely but unsuitable for application in WWTP. Therefore, granular activated carbon (GAC) adsorption and ultra violet (UV) photolysis were developed in chapter V and VI as removal and degradation processes respectively.  Fifteen kinds of PFCs were included in this study, consisting of twelve kinds of perfluorocarboxylic acids (PFCAs) with 4~18 carbons and three kinds of perfluoroalkyl sulfonates (PFASs) with 4~8 carbons. An integral procedure was developed in chapter III to pretreat wastewater samples. LC-ESI-MS/MS was applied to quantify all PFCs in trace level. Pretreatment methods were optimized between C18 and WAX-SPE processes for aqueous samples, and between IPE, AD-WAX and ASE-WAX processes for particulate samples. Standard spiking experiments were regularly conducted for each wastewater sample to calculate recovery rate and control analytical quality. As the result, WAX-SPE showed better performance on samples with very high organics concentrations, and C18-SPE performed better for long-chained PFCs. ASE-WAX was proposed as the optimum method to pretreat particulate samples because of the simple and time saving operations. 9H-PFNA was used as internal standard to estimate matrix effect in wastewater.  Behavior of PFCs in a municipal WWTP has been studied in chapter IV by periodical surveys for six times in half a year. All PFCs used in this study were detected in WWTP influent and effluent. According to their carbon chain lengths, all PFCs can be classified into “Medium”, “Long” and “Short” patterns to simplify behavior analysis. PFCs in same pattern showed similar properties and behavior in wastewater treatment facilities. Very high concentrations of PFCs existed in WWTP influent, indicating some point sources of industrial discharge in this area. “Medium” PFCs, such as PFOA(8), PFNA(9) and PFOS(8), were primary contaminants in the WWTP and poorly removed by overall process. Performances of individual facilities were estimated for removal of each PFC. Primary clarification and secondary clarification were helpful to remove all PFCs in both aqueous phase and particulate phase. “Medium” PFCs in aqueous phase were increased after activated sludge process, but other PFCs can be effectively removed. Ozone seemed ineffective to decompose PFCs because of the strong stability of PFC molecules. Sand filtration and biological activated carbon (BAC) filtration in this WWTP can not remove PFCs effectively too, which required further studies. Performances of combined processes were estimated by integrating individual facilities along the wastewater flow. Activated sludge process coupled with clarifiers showed satisfied removal of most PFCs in the investigated WWTP except “Medium” PFCs.  Adsorption characteristics of PFCs onto GAC have been studied by batch experiments in chapter V. Freundlich equation and homogenous surface diffusion model (HSDM) were applied to interpret experimental data. Isothermal and kinetics experiments implied that PFC adsorption on GAC was directly related with their carbon chain lengths. By ascendant carbon chain length, adsorption capacity for specific PFC was increased, and diffusion coefficient (Ds) was decreased. Ds of GAC adsorption was also decreased gradually in smaller GAC diameters. Coexisted natural organic matters (NOMs) reduced adsorption capacities by mechanism of competition and carbon fouling. Carbon fouling was found reducing adsorption capacity much more intensively than competition by organics. Acidic bulk solution was slightly helpful for adsorption of PFCs. However adsorption velocity or kinetics was not affected by NOM and pH significantly. GAC from Wako Company showed the best performance among four kinds of GACs, and Filtra 400 from Calgon Company was considered more suitable to removal all PFCs among the commercial GACs. Preliminary RSSCT and SBA results implied that background organics broke through fixed GAC bed much earlier than trace level of PFCs. Medium-chained PFCs can be effectively removed by fixed bed filtration without concerning biological processes.  Direct photolysis process has been developed in chapter VI to decompose PFCAs in river water. Irradiation at UV254 nm and UV254+185 nm can both degrade PFCAs. Stepwise decomposition mechanism of PFCAs was confirmed by mass spectra analysis, and consecutive kinetics was proposed to simulate experimental data. PFASs can also be degraded by UV254+185 photolysis, although the products have not been identified yet. Coexisted NOMs reduced performance of UV photolysis for PFCAs by competition for UV photons. Sample volume or irradiation intensity showed significant influence on degradation of PFCAs. Local river water polluted by PFOA can be cleaned up by UV254+185 photolysis effectively. Ozone-related processes were also studied but ineffective to degrade PFC molecules. However, PFCs could be removed in aeration flow by another mechanism. / 京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第13340号 / 工博第2837号 / 新制||工||1417(附属図書館) / UT51-2007-M963 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 藤井 滋穂, 教授 伊藤 禎彦 / 学位規則第4条第1項該当 / Doctor of Engineering / Kyoto University / DFAM

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