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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.
91

Nitrifikation i pulskärr : En studie av Forsmarks avloppsreningsverk med SBR och våtmarker / Nitrification in vertical flow intermittent loaded soil filter wetland : A study of Forsmark wastewater treatment plant with SBR and constructed wetlands

Halvarsson, Linus January 2017 (has links)
Avloppsreningsverket i Forsmark renar vattnet med aktivt slam i en satsvis biologisk rening (SBR) reaktor samt med våtmarker. Våtmarkerna består av fyra pulskärr och en damm. Pulskärren är utformade som bassänger fyllda med grus som filtermaterial där ytan är bevuxen. Pulskärren beskickas satsvis med 60 m^3 vatten när någon av SBR-reaktorerna töms, vattnet rinner då ut över ytan samtidigt som det perkolerar ner i bädden. När SBR-reaktorn har tömts är hela pulskärret mättat. Tömningen av pulskärret sker genom ett dränerande gruslager i botten och sedan flödar vattnet vidare ut genom ett ställbart dräneringsrör till slutdammen. Pulskärrens uppgift är att stoppa partiklar och att fungera som ett nitrifierande steg ifall verket i framtiden skulle få ökade reningskrav. I detta arbete har pulskärrens funktion som nitrifierare av ammonium undersökts. Detta genom att sammanställa befintliga driftdata från reningsverket, fältstudier samt en litteraturgenomgång. Målet med fältstudien var att mäta halten ammonium, nitrat och totalkväve i vattnet som gick in och ut ur pulskärret för att se hur halterna ändrades. Dessutom mättes temperatur, syrehalt, pH och konduktivitet. Provtagningen genomfördes på två pulskärr med tömningstiderna två respektive fyra timmar. Resultaten visade att ammoniumhalterna halveras i pulskärren. Inkommande ammonium till pulskärren var cirka 3 mg/l under studien men om ammoniumkoncentrationen skulle öka kommer nitrifikationen antagligen ske i liknande utsträckning. Detta då liknande system påvisat sådana resultat. Ökad tömningstid för pulskärren medför ökad nitrifikation, pulskärren bör därför ställas om så att tömning sker under cirka fyra timmar. För att hitta en optimal tömningstid bör vidare undersökningar göras. Forsmarks avloppsreningsverk möter de reningskrav som ställts med marginal. Trots att detta inte var syftet, avskiljs 80 % av inkommande kväve och det kunde konstateras att den största kväveavskiljningen sker i SBR-reaktorn. Kvävereduktionen har uppstått då verket haft låg belastning samtidigt som mycket syre tillsatts till processen. Då rening genom pulskärr sker efter att vattnet passerat genom SBR-reaktorerna borde luftningen kunna minskas för att istället utnyttja pulskärrens nitrifierande egenskaper. Svensk kärnbränslehantering AB har planer på att leda lakvatten till reningsverket för att avskilja kväverester, skulle detta ske kommer flödena över pulskärren att öka. Att den hydrauliska belastningen ökar borde inte utgöra några problem då flödena troligen inte kommer överstiga pulskärrens kapacitetsgränser. I extrema fall kan tömningstiden på pulskärren minskas. / Forsmark wastewater treatment plant treats wastewater using an active sludge process in sequencing batch reactors (SBR:s) and followed by constructed wetlands. The wetlands consist of four intermittent loaded soil filters (ILS:s) and a pond. The ILS:s is designed as pools filled with filter material and with a plant-grown surface. One of the ILS:s fills up with water when one of the SBR reactors is emptied. The water flows out over the surface as it percolates into the bed. When the SBR reactor is emptied, the entire ILS becomes saturated. The ILS then drains through a drainage gravel layer at the bottom and further through an adjustable drainage pipe into the dam. The purpose of the ILS:s is to work as extra filter for removal of the remaining particles and escaping sludge. They have also been thought to act as a nitrifying step if the plant would have tougher cleaning requirements in the future. In this report, the function of the ILS:s as nitrifying steps was investigated by compiling existing operating data from the treatment plant, with conducted field studies and through a literature review. The field study aimed at measuring ammonium, nitrate and total nitrogen in the water at the entering and the outlet in the ILS to see how the different nitrogen concentrations was affected. Temperature, oxygen, pH and electricalconductivity were also measured. The sampling was done on two ILS with different drainage time, two and four hours. The results showed that the ILS:s nitrifies the incoming water with an average efficiency of 50 % depending on the ammonium contentration in the incoming water. An increased drainage time for the ILS seamed to result in better nitrification. Therefore, the ILS:s should be changed to drain for at least four hours. Should the ammonium concentration increase above 3 mg/l the nitrification rate would probably be about the same. Similar systems such as have shown similar nitrification removal but with higher ammonia concentrations. Forsmarks wastewater treatment plant meets the purification requirements imposed on the plant with margin. It is remarkable that, without planning for any nitrogen removal, the removal is about 80 % of incoming nitrogen, most of which is removed in the SBR reactor. Svensk Kärnbränslehantering AB plans to lead leachate to the treatment plant for nitrogen removal. If this plan is fulfilled, the flows through the ILS will increase. This should not be a problem as the total flow trought the ILS will not exceed the capacity limits of the ILS. In case of high flows, the emptying time of the ILS:s can be reduced.
92

Valoração ambiental e analise de viabilidade economica : o caso da estação escola de tratamento de esgotos da Universidade Estadual de Campinas / Environmental valuation and analysis of economical viability : the case of school wastewater treatment plant of State University of Campinas

Machion, Ane Caroline Grisolio 17 July 2006 (has links)
Orientador: Jose Roberto Guimarães / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-07T16:39:23Z (GMT). No. of bitstreams: 1 Machion_AneCarolineGrisolio_M.pdf: 8431121 bytes, checksum: 6a5866ab77e4d74302c23bf3d221b93e (MD5) Previous issue date: 2006 / Resumo: Um dos problemas ambientais urbanos mais graves é a falta de tratamento do esgoto sanitário que, freqüentemente despejado in natura em corpos d¿água, causa danos, por vezes irreversíveis, às reservas de água potável comprometendo e restringindo seu uso. A presente pesquisa tem como objetivos caracterizar os investimentos necessários à construção da Estação Escola de Tratamento de Esgotos da Universidade Estadual de Campinas aplicando-se um método de valoração ambiental e analisar a viabilidade econômica destes investimentos considerando-se o reúso do efluente tratado. A metodologia consiste em caracterizar o objeto de estudo e o seu entorno, construir cenários referentes à qualidade ambiental do rio receptor do efluente da UNICAMP e simular o fluxo de caixa para o cálculo dos indicadores econômicos / Abstract: One of the most serious urban environmental problems is the lack of sanitary wastewater treatment which frequently is discharged in natura in water bodies causing damages, sometimes irreversible, to potable water reservations compromising and restricting their use. The present research has as objectives to characterize the necessary investments for the building of School Wastewater Treatment Plant at State University of Campinas applying a valuation method and to analyze the economical viability of these investments considering the treated effluent reuse. The methodology consists in characterizing the object of study and its surrounding, to build sceneries referring to environmental quality of the receiver river of UNICAMP¿s effluent and to simulate the cash flow for the economic indicators calculation / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
93

Utvärdering av effektivitet för aktivt kol och anjonbytare vid reduktion av per- och polyfluorerade alkylsubstanser (PFAS) samt läkemedelssubstanser i avloppsvatten

Kalecinska, Monika January 2021 (has links)
Avloppsreningsverk (ARV) utgör en viktig del som spridningsväg för utsläpp av organiska mikroföroreningar, som per- och polyfluorerade alkylsubstanser (PFAS) och läkemedelssubstanser, från samhället till den akvatiska miljön. Befintliga reningssteg vid ARV reducerar mikroföroreningar dåligt varav denna studie syftade till att jämföra reduktionseffektiviteten av 5 olika granulära aktiva kol (GAK) och en anjonbytare (AIX) för att välja ut det material som är mest lämpat för vidare undersökningar i pilotskala inför installation ett avancerat reningssteg i Kungsängsverkets ARV i Uppsala. GAK (Filtrasorb 400, Cyclecarb 401, Brennsorb 1240, Aquasorb 5000 och Aquasorb 2000) utvärderades för avskiljning av 13 PFAS-ämnen i ett inledande bägarförsök genom placering i avloppsvatten från Kungsängsverket i 8 h. Cyclecarb 401 var mest effektivt vid avskiljning av PFAS där reduktionsgraden för PFAS-11 (85 %) och PFOS (90 %) var 35 % och 40 % högre än för det minst effektiva GAK Brennsorb 1240. Cyclecarb 401, Brennsorb 1240 och AIX Purolite 694E undersöktes i ett andra bägarförsök enligt en liknande metod, men utvärderades med avseende på avskiljning av 12 PFAS och 18 läkemedelssubstanser över 48 h. Resultatet för PFAS var likvärdigt för GAK, men AIX visades nå samma reduktionsgrad av PFAS som Cyclecarb 401 och detta skedde snabbare. Efter 48 h var reduktionen med GAK högst för läkemedelssubstanser (91-99 %) och med AIX för PFAS (78 %). Samtliga adsorbenter tillfördes även till kolonner, där Purolite 694E även seriekopplades efter Cyclecarb 401, med ett kontinuerligt flöde av avloppsvatten motsvarande 5 min kontakttid (EBCT). Även om duplikatprover togs varje vecka genomfördes inom ramen för detta examensarbete analyser för de prover tagna en timme (12 bäddvolymer), 2 veckor (4000 bäddvolymer) och 7 veckor (14 000 bäddvolymer) efter start för 12 PFAS och 18 läkemedelssubstanser. Purolite 694E reducerade PFAS bäst, 40-50 % bättre än GAK, följt av negativt laddade läkemedelssubstanser och adsorptionen för dessa ämnen var bättre över tid än för GAK. Seriekoppling av AIX efter GAK förbättrade reduktionsgraden över tid för främst PFAS (30 % ökning vid 14 000 bäddvolymer). Även för läkemedelssubstanser med negativ laddning som adsorberades väl av AIX. Adsorptionen till AIX gynnades mest av substanser med negativa laddning. Adsorptionen till samtliga adsorbenter gynnades av PFAS med en sulfonatgrupp, en lägre syrakonstant, en högre fördelningskonstant mellan oktanol och vatten samt en längre kolkedja. En seriekoppling av AIX efter GAK är främst intressant för förbättrad avkiljning av diklofenak och PFOS vid Kungsängsverket, men även avskiljning av andra PFAS och negativt laddade läkemedelssubstanser kan förbättras. Andra ämnen adsorberades väl av GAK där Cyclecarb 401 i samtliga försök visats mest effektiv. De analyserade provpunkterna för kolonnförsöket var för få varav en kommande noggrannare undersökning över hela försökets genomförande kommer påvisa livslängderna för varje adsorbent vid EBCT 5 min. EBCT var kort varav efterföljande försök bör undersöka avskiljningens effektivitet för Kungsängsverket vid längre EBCT. / Waste water treatment plants (WWTPs) constitute an important role in releasing organic micropollutants, such as per- and polyfluoroalkyl substances (PFAS) and pharmaceuticals, from the society into the aquatic environment. Reduction of them in existing treatment methods in WWTPs is insufficient which is why the aim of this study was to examine the reduction efficiency for 5 granular activated carbons (GAC) and an anion exchange resin (AIX) and choose the adsorbent most suited for further studies in pilot scale before an advanced treatment step is built to Kungsängsverket WWTP in Uppsala.  GAC (Filtrasorb 400, Cyclecarb 401, Brennsorb 1240, Aquasorb 5000 and Aquasorb 2000) were evaluated for 13 PFAS compounds in an initial batch experiment using wastewater from Kungsängsverket during 8 h. Cyclecarb 401 had the highest removal efficiency for PFAS where the reduction grade for PFAS-11 (85 %) and PFOS (90 %) was 35 % and 40 % higher than for the least efficient GAC Brennsorb 1240. Cyclecarb 401, Brennsorb 1240 and the AIX Purolite 694E were evaluated in a second batch experiment through a similar method, analyzed for 12 PFAS and 18 pharmaceuticals over 48 h. The results for PFAS were similar for GAC, but AIX reached the same reduction grade for PFAS as Cyclecarb 401 which also happened faster. After 48 h reduction with GAC was best for pharmaceuticals (91-99 %) and with AIX for PFAS (78 %). Finally, these adsorbents were placed in individual columns, where Cyclecarb 401 was connected to an additional column with Purolite 694E, with a continuous flow of wastewater with an empty bed contact time (EBCT) of 5 min. Even though duplicate samples were taken each week analysis was performed for samples taken an hour (12 bed volumes), 2 weeks (4000 bed volumes) and 7 weeks after start (14 000 bed volumes) for 12 PFAS and 18 pharmaceuticals. Purolite 694E reduced PFAS the best, 40-50 % better than GAC, followed by negatively charged pharmaceuticals and adsorption for these compounds was better over time than with GAC. AIX after GAC increased reduction grade over time primarily for PFAS (30 % improvement after 14 000 bed volumes) but also for pharmaceuticals well adsorbed by AIX. Adsorption to AIX was mainly improved with a negative charge of the compound. Adsorption to adsorbents was favored for PFAS containing a sulfonate group, compounds with a lower acid dissociation constant, a higher octanol-water partition coefficient and a longer carbon chain. Implementation of AIX after GAC would be of interest for Kungsängsverket mainly due to the improved removal of diclofenac and PFOS, but also if removal of other PFAS and pharmaceuticals will become prioritized. Other compounds were removed by GAC well where Cyclecarb 401 was most effective in all experiments. The analyzed samples for the column experiment were too few which is why a more comprehensive study of all samples over the whole experiment period will be able to determine the life length of each adsorbent for EBCT 5 min. EBCT was short which is why further experiments need to examine the reduction efficiency for Kungsängsverket at a longer EBCT.
94

Studie variant odkanalizování obce Crhov / The study alternatives village sewer system Crhov

Sakáčová, Monika January 2018 (has links)
The theme of this diploma thesis is " The study alternatives village sewer system Crhov". The thesis focuses on the design of possible wastewater treatment options with design of the technology for waste water treatment. Four alternatives are proposed - catch up existing sewerage and build an aerobic pond, new sewerage system with a container sewage treatment plant, domestic sewage treatment plant and the existing drainage system and the construction of a sewage treatment plant. In addition to the proposal itself, financial valuation of these variants is an integral part of the work with its own recommendation.
95

Studie odkanalizování vybrané obce / Study of sewer network of selected municipality

Remešová, Terezie January 2019 (has links)
The main goal of this diploma thesis is the proposal of sewerage variants of local parts of village Pačlavice, which are villages Pornice and Lhota. For individual municipalities are proposed three partially different variants, which vary mainly in the way of wastewater draining and wastewater treatment. All three variants are evaluate from an economic and technical point of view and on the basis of evaluation is propose a variant, which is in my opinion, the most suitable for these municipalities. In the villages Pornice, Lhota and Pačlavice are proposed new delivery and gravity sections, associated objects of overflow chambers with pumping stations, independent overflow chambers or separate pumping stations that complement the existing combined sewer system to ensure the drainage of wastewater to wastewater treatment plant and following treatment of this water.
96

Intenzifikace stávající čistírny odpadních vod technologií MBR / Upgrading of wastewater treatment plant by means of MBR technology.

Spratková, Aneta January 2019 (has links)
This diploma thesis is focused on the topic of membrane technologies used in wastewater treatment. The research part of the thesis deals with membrane separation of activated sludge, and the focus is on the submerged membrane modules. The thesis contains basic principles of MBR systems, an overview of used membrane modules, modes of operation, advantages and disadvantages of using this process. The practical part of the thesis proposes the intensification of WWTP Perná with using MBR technology. This part includes the technical-economic assessment of the activation WWTP with the third stage of treatment and activation WWTP with MBR.
97

Optimalizace provozu čistíren odpadních vod / Optimizing the operation of wastewater treatment plants

Singrová, Veronika January 2019 (has links)
The aim of this diploma thesis is to evaluate two selected wastewater treatment plants and to propose appropriate measures related to optimization of operation. Wastewater treatment plants are from the Jihomoravský and Zlínský regions and both come under the category 2 001 - 10 000 equivalent inhabitants. In the diploma thesis there is an assessment of construction objects, machinery, cleaning efficiency and energy performance of both WWTPs. The calculations are based on the real measured values for the last three years and on the basic parameters of individual objects and equipment. The present state of the two wastewater treatment plants is summarized and optimization proposals are sorted by importance.
98

Studie variant odkanalizování obce do 2000 EO / The study alternatives village up to 2000 PE

Krupicová, Simona January 2020 (has links)
The diploma thesis deals with the design of variants of sewerage and wastewater disposal in the selected municipality. Solved area for this work is the village Rovečné with the local part of Malé Tresné. The aim of this work is to propose a suitable variant and to assess it from the economic point of view with regard to grant titles. The author deals with the selection of a suitable method of sewerage of the area of interest and subsequent waste water disposal, based on the relevant standards and related regulations. The proposed options are then assessed from an economic point of view and a suitable solution option is recommended.
99

Studie variant odkanalizování rekreačního střediska Vřesovice / Study of variants of sewerage of the recreational center Vřesovice

Krulová, Martina January 2021 (has links)
The diploma thesis deals with the possibilities of sewerage and wastewater disposal in the recreational centre near Vřesovice. The purpose of the diploma thesis is the elaboration of variant solutions of sewerage, including the proposal of possibilities of wastewater treatment, economic evaluation of variants, their subsequent comparison and recommendation of the most suitable variant. The diploma thesis deals with the design of variants of wastewater treatment with subsequent discharge into surface waters. Finally, the advantages and disadvantages of the individual variants of sewerage are summarized with a comparison of costs and subsequent recommendation of the variant.
100

Zdravotně technické instalace ubytovacích zařízení / Plumbing Systems for Accommodation Facilities

Možná, Pavlína January 2013 (has links)
Master’s thesis "Plumbing systems for accommodation facilities" is processed in the form of project documentation plumbing according to applicable regulations. Designed building has five floors, basement. The ground floor restaurant and relaxing part of the hotel, in the remaining floors are guest rooms with 75 beds. One room is completely wheelchair. The building is located outside urban areas without connection to public utilities. The work focuses on the design of plumbing hotel and presents two variants of the possible solutions for waste water from the building. Building water supply is secured from drilled wells and the proposed pumping equipment.

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