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Processo de tratamento biológico e físico-químico combinados visando o reúso de esgoto sanitário / Biological treatment process and physical-chemical combinations aiming reuse sewageOliveira, Gabriela Laila de 01 June 2012 (has links)
Este trabalho teve por objetivo avaliar a combinação de processos de tratamento de esgoto e a partir dos efluentes produzidos com diferentes padrões de qualidade elencar as possibilidades para reúso de acordo com legislação internacional. Foi feito o monitoramento da estação piloto de tratamento de esgoto constituído reator UASB seguido de lodo ativado cujos efluentes foram utilizados neste estudo, não somente para análises físico-químicas e microbiológicas, mas também para posterior tratamento físico-químico em laboratório com equipamento jarteste utilizando dois coagulantes - cloreto férrico e sulfato de alumínio. Após os tratamentos combinados seis amostras diferentes foram analisadas, sendo elas: efluente do UASB, efluente do lodo ativado, tratamentos UASB-\'AL IND.2\'(\'SO IND.4\')IND.3\', UASB-\'FE\'CL IND.3\', lodo ativado-\'AL IND.2\'(\'SO IND.4\')IND.3\' e lodo ativado-\'FE\'CL IND.3\'. Os ensaios realizados com cloreto férrico foram os que melhor promoveram remoção dos microrganismos indicadores e de (oo)cistos, de DQO e SST. Porém, mesmo após o tratamento físico-químico não será possível reutilização agrícola, urbana e/ou industrial dos efluentes, conforme legislação internacional e diretrizes da OMS, uma vez que a concentração de microrganismos indicadores ainda é muito elevada. Os valores médios de E. coli, coliformes totais e Giardia spp., mesmo após o tratamento que forneceu melhor remoção microbiológica (lodo ativado \'FE\'CL IND.3\') foram de 4,31 x \'10 POT.2\', 7,68 x \'10 POT.3\' e 2,17 x \'10 POT.2\', respectivamente. / The present dissertation reports to evaluate the combination of process wastewater treatment and from the effluent produced with different standards quality list the possibilities for reuse in accordance with international Law. Was monitored from the wastewater treatment plant pilot consists of a UASB reactor followed by activated sludge whose effluents were used in this study not only physical-chemical and microbiological analyzes, but also for subsequent physical-chemical treatment in the laboratory with equipment jartest using two coagulants ferric chloride and aluminum sulfate. After the treatments combined six different samples were analyzed: UASB effluent, activated sludge effluent, treatments UASB-\'AL IND.2\'(\'SO IND.4\')IND.3\', UASB-\'FE\'CL IND.3\', activated sludge-activated sludge and activated sludge-\'FE\'CL IND.3\'. The tests with ferric chloride were better promoted removal of the microbiological indicators and (oo)cysts, COD and TSS. However, even after physical-chemical treatment will not be possible wastewater reuse in agriculture, urban and/or industrial, according international law and the WHO guidelines, since the concentration of indicator microorganisms is still very high. The average values of E. coli and total coliform and Giardia spp., even after the treatment which promoted better microbiological removal, were 4,31 x \'10 POT.2\', 7,68 x \'10 POT.3\' e 2,17 x \'10 POT.2\', respectively.
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Tratamento biológico termofílico de efluente sintético de polpa celulósica através do processo combinado anaeróbio-aeróbio / Thermophilic treatment biologic of synthetic effluent from unbleached cellulose pulp through combined system anaerobic-aerobicDirlane de Fátima do Carmo 25 June 2004 (has links)
A viabilidade técnica de um sistema termofílico combinado de reatores anaeróbio-aeróbio foi avaliada para tratamento de efluente sintético da indústria de pasta de celulose não branqueada. Estas indústrias apresentam efluente com temperatura superior a 40ºC e o tratamento termofílico pode eliminar a necessidade do resfriamento, necessário para a faixa mesofílica de tratamento, reduzindo custos. Os reatores foram inoculados com lodo mesofílico com gradual adaptação para a condição termofílica. Na faixa mesofílica (37,5 a 42,5ºC) a eficiência do sistema foi de (69±3)%, com maior eficiência do reator anaeróbio (56±7)%. Depois que os reatores apresentaram equilíbrio dinâmico aparente, a temperatura foi gradualmente aumentada de 45,0 para 52ºC. As eficiências de remoção de DQO do sistema variaram de 57% a 88%. A porcentagem de metano no biogás foi decrescendo com o aumento de temperatura, de 77% para valores abaixo do limite de detecção do método cromatográfico utilizado. A eficiência do reator anaeróbio foi baixa e houve acúmulo de ácidos, principalmente acético. O reator aeróbio apresentou maior eficiência de remoção de DQO porém a concentração no licor misto foi baixa. Após a alteração no tempo de detenção hidráulica dos reatores UASB e de lodos ativados para 24 horas e 8 horas, respectivamente, os reatores operaram em faixa de temperatura de 52 a 57ºC por 85 dias. As eficiências de remoção de DQO do sistema variaram de 54% a 70%. A eficiência do reator UASB continuou baixa enquanto o reator aeróbio apresentou bom desempenho, com eficiências variando de 3% a 35% e de 43% a 75%, respectivamente. As concentrações de SSV no licor misto aumentaram, variando de 122 mg/L a 2940 mg/L. Em faixa de temperatura termofílica houve predomínio de Methanosaetas sp e bacilos no reator anaeróbio, não havendo diferenciação significativa de morfologias comparando com a fase mesofílica. No reator aeróbio houve diferenciação a partir da temperatura de 42,5ºC e predominaram bacilos, cocos e filamentos em temperatura termofílica. Os resultados demonstram a viabilidade do tratamento termofílico, mas outros experimentos são necessários antes da aplicação industrial do processo. / The technical feasibility of a combined thermophilic anaerobic-aerobic biological reactors configuration was evaluated in this work using a synthetic unbleached pulp mill effluent. These industries introduce effluent with temperature greater 40ºC and the treatment would eliminate the need of cooling that is required for the mesophilic range, reducing the costs. The reactors were inoculated with mesophilic sludge with gradual adaptation to the termophilic condition. In the mesophilic range (37.5 to 42.5ºC) the efficiency of the combined system was (69±3)%, with the higher efficiency in the anaerobic reactor (56±7)%. After the reactors reached apparent steady state regime the temperature was gradually increased from 42.5 to 52ºC. The system efficiency ranged from 57% to 88%. The percentage of methane in the biogas decreased with the increase in temperature, from 77% to values below the detection limit of the chromatographic measurement used in this work. The anaerobic efficiency was low and the reactor accumulated fatty acid, mostly acetic. The aerobic reactor presented higher efficiency removal of COD but the mixed liquor concentration was lower. After adjustment in the hydraulic retention time of both reactors, with the UASB operating with 24 hours HRT and the aerobic with 8 hours HRT, the reactors operated in the temperature range of 52 to 57ºC during 85 days. The overall removal efficiency ranged from 54% to 70%. The efficiency of the UASB reactor remained lower while the aerobic reactor presented good performance, with COD removal efficiency in the range of 3% to 35%, respectively. The mixed liquor VSS concentration increased with the increase in temperature from 122 mg/L to 2940 mg/L. In thermophilic temperature there was predominance of Methanosaetas sp and baccilus in the anaerobic reactor, without significant differentiation of morphology in comparison with the mesophilic temperature. In the aerobic reactor there was differentiation in temperature of 42.5ºC and baccilus, cocus and filamentous predominated in the thermophilic temperature. These results indicated the feasibility of the thermophilic treatment but other experiments are needed before industrial application of this process.
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Comparison of Bacterial and Viral Reduction Across Different Wastewater Treatment ProcessesVagadia, Aayushi R. 01 November 2018 (has links)
Today billions of people live without access to basic sanitation facilities, and thousands die every week due to diseases caused by fecal contamination associated with improper sanitation. It has thus become crucial for decision makers to have access to relevant and sufficient data to implement appropriate solutions to these problems. The Global Water Pathogen Project http://www.waterpathogens.org/ is dedicated to providing an up-to-date source of data on pathogen reduction associated with different sanitation technologies that are important if the world is to achieve the Sustainable Development Goals (SDGs) related to health and sanitation provision. In this research, a subset of the Global Water Pathogen Project (GWPP) data is used to access the reduction of bacteria and viruses across different mechanical and natural sanitation technologies. The order of expected removal for bacteria during wastewater treatment was reported as highest for a membrane bioreactor (4.4 log10), waste stabilization pond (2.3 log10), conventional activated sludge (1.43 log10), anaerobic anoxic oxic activated sludge (1.9 log10), trickling filter (1.16 log10), and upflow anaerobic sludge blanket reactor (1.2 log10).
Furthermore, the order of expected removal for viruses was reported as highest for a membrane bioreactor (3.3 log10), conventional activated sludge (1.84 log10), anaerobic anoxic oxic activated sludge (1.67 log10), waste stabilization pond (1 log10), upflow anaerobic sludge blanket reactor (0.3 log10) and trickling filter (0.29 log10). It was found that hydraulic retention time (HRT) had a statistically significant relation to the reduction of bacteria in an anaerobic, anoxic oxic treatment system. Similarly, a significant relation was found between the number of waste stabilization ponds in series and the expected reduction of bacteria. HRT was also found to be a significant factor in virus reduction in waste stabilization ponds. Additionally, it was observed that waste stabilization ponds, trickling filters, and UASB reactors could obtain a greater reduction in bacteria (5-7 log10) when combined with additional treatment (e.g., chemical disinfection or use of maturation ponds). Also, mechanized systems, such as activated sludge systems and membrane bioreactors, obtained a greater reduction (2-3 log10) of viruses when compared to a natural system. It was concluded that the selection of the best suitable technology for pathogen reduction depends on environmental, design, and operational factors as well as considering the performance of specific wastewater treatment systems individually as well as when combined with other treatment technologies that may provide added removal of microbial constituents.
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Antibiotic Resistance in Wastewater : Methicillin-resistant Staphylococcus aureus (MRSA)and antibiotic resistance genes / Resistenta gula stafylokocker (MRSA) och antibiotikaresistensgener förekommer i svenskt kommunalt avloppsvattenBörjesson, Stefan January 2009 (has links)
A large part of the antibiotics consumed ends up in wastewater, and in the wastewater the antibiotics may exert selective pressure for or maintain resistance among microorganisms. Antibiotic resistant bacteria and genes encoding antibiotic resistance are commonly detected in wastewater, often at higher rates and concentrations compared to surface water. Wastewater can also provide favourable conditions for the growth of a diverse bacterial community, which constitutes a basis for the selection and spread of antibiotic resistance. Therefore, wastewater treatment plants have been suggested to play a role in the dissemination and development of antibiotic resistant bacteria. Methicillin-resistant Staphylococcus aureus (MRSA) is a large problem worldwide as a nosocomial pathogen, but knowledge is limited about occurrence in non-clinical environments, such as wastewater, and what role wastewater plays in dissemination and development of MRSA. In this thesis we investigated the occurrence of MRSA in a full-scale wastewater treatment plant (WWTP). We also investigated the concentration of genes encoding resistance to aminoglycosides (aac(6’)-Ie+aph(2’’)), β-lactam antibiotics (mecA) and tetracyclines (tetA and tetB) in three wastewater-associated environments: (1) soil from an overland flow area treating landfill leachates, (2) biofilm from a municipal wastewater treatment plant, and (3) sludge from a hospital wastewater pipeline. In addition, concentrations of mecA, tetA and tetB were investigated over the treatment process in the WWTP. These investigations were performed to determine how the prevalence and concentration of MRSA and the antibiotic resistence genes are affected in wastewater and wastewater treatment processes over time. The occurrence of MRSA was investigated by cultivation and a commercially available real-time PCR assay. In order to determine concentrations of the genes aac(6’)-Ie+aph(2’’), mecA, tetA and tetB in wastewater we developed a LUXTM real-time PCR assay for each gene. Using cultivation and real-time PCR we could for the first time describe the occurrence of MRSA in wastewater and show that it had a stable occurrence over time in a WWTP. MRSA could mainly be detected in the early treatment steps in the WWTP, and the wastewater treatment process reduced the number and diversity of cultivated MRSA. However, our results also indicate that the treatment process selects for strains with more extensive resistance and possibly higher virulence. The isolated wastewater MRSA strains were shown to have a close genetic relationship to clinical isolates, and no specific wastewater lineages could be detected, indicating that they are a reflection of carriage in the community. Taken together, these data indicate that wastewater may be a potential reservoir for MRSA and that MRSA are more prevalent in wastewater than was previously thought. The real-time PCR assays, for aac(6’)-Ie+aph(2’’), mecA, tetA, and tetB that we developed, were shown to be sensitive, fast, and reproducible methods for detection and quantification of these genes in wastewater environments. The highest concentrations of all genes were observed in the hospital pipeline, and the lowest in the overland flow system, with tetA and aac(6´)-Ie+aph(2´´) detected in all three environments. In the full-scale WWTP, we continuously detected mecA, tetA and tetB over the treatment process and over time. In addition, it was shown that the treatment process reduces concentrations of all three genes. The data presented in this thesis also indicate that the reduction for all three genes may be connected to the removal of biomass, and in the reduction of tetA and tetB, sedimentation and precipitation appear to play an important role.
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Kemisk karaktärisering samt nedbrytning av process- och avloppsvatten vid SCA Ortvikens pappersbruk / Chemical characterization and degradation of oxygen demanding compounds in process- and wastewater at SCA Ortviken's paper millBlixt, Ann January 2006 (has links)
During pulp and papermaking process a huge amount of water is used. The wastewater contains a large amount of pollutants and has to be treated before it reaches the recipient. In March 2004 a new bleaching plant was started up at SCA Graphic Sundsvall AB, Ortviken’s paper mill using peroxide. The production of bleached thermo mechanical pulp and thus the load to the wastewater plant increased. During bleaching substances dissolve from the pulp and the amount of COD in the wastewater increase. To keep the efficiency of chemical and biological oxygen demand (COD, BOD) removal, the aerated lagoon is supplied by liquid oxygen. In November the same year a new pre-step including a pre-aeration, carrier and selector step was added to the existing wastewater plant. The COD-loading to the lagoon decreased and the supply of liquid oxygen was reduced. This master thesis has been carried out at SCA Graphic Research AB, Sundsvall. The aim was to chemically characterize the wastewater with focus on the composition of carbohydrates, lignin and extractives and its influence on the biodegradability. Measurements have been carried out on total samples, suspended solids, colloidal and dissolved substances using GF/A and ultra filtration. Measurements were performed on process water from the bleaching plant and on water during the wastewater treatment process. The results show that the chemical composition of dissolved substances has a larger impact on the biodegradability than the total amount of COD. A large amount of lignin will make the wastewater harder to degrade. Suspended solids have lower biodegradability compared to the dissolved fraction. Analyzes of suspended material from the bleaching plant show a relative composition of around 41 % lignin. Analyzes done before on the dissolved fraction show a composition of 29 %. It seems that a larger amount of lignin is represented in suspended solids compared to the dissolved fraction. This can explain the low biodegradability, combined with the theory that the suspended solids are less accessible for the microorganisms. To reduce the outgoing COD the incoming flow of dissolved lignin and suspended solids to the active sludge plant has to decrease. COD in the outgoing wastewater to the recipient consists of around 90 % lignin. Extractives as saturated fatty acids, palmitic and stearic acid plus lignans (which is interpreted as a byproduct from lignin degradation) do not degrade remarkable during wastewater treatment. Flocculation of COD is one way to reduce the discharge to the recipient. Addition of 2,6 g/l PAX-18 (a high charged aluminum complex) to the wastewater from the bleaching plant gives a reduction of 40 % COD and 50 % lignin in laboratory scale and it is recommended to study further. Time related studies of BOD show that the microorganisms need five days to degrade organic material and the hydraulic retention time in the aerated lagoon has to be guaranteed. / Vid massa- och pappersframställning åtgår stora mängder vatten. Det processberörda avloppsvattnet innehåller mycket föroreningar varför det måste renas innan det släpps ut till recipienten. I mars 2004 startades ett nytt väteperoxidblekeri vid SCA Graphic Sundsvall AB, Ortvikens pappersbruk varvid produktionen av blekt termomekanisk massa ökade och den biologiska reningen belastades hårdare. Blekning löser ut vedämnen från massan och bidrar således till ökad mängd syreförbrukande ämnen i avloppet. För att upprätthålla reduktionen av syreförbrukande ämnen (COD, BOD) tillförs ren syrgas till den luftade dammen. I november samma år utökades den externa reningsanläggningen med ett biologiskt försteg, en s.k. multibioanläggning bestående av ett frisimmarsteg, ett bärarsteg samt ett selektorsteg. COD-belastningen in till den luftade dammen minskade och tillförseln av ren syrgas kunde reduceras. Examensarbetet har utförts vid SCA Graphic Research AB, Sundsvall med syftet att kemiskt karaktärisera avloppsvattnets sammansättning av kolhydrater, lignin och extraktivämnen och dess inverkan på vattnets grad av biologisk nedbrytbarhet. Analyser har gjorts på totalprov, suspenderande ämnen samt kolloidalt och löst material via fraktionering med hjälp av GF/A- och ultrafiltrering. Analyser gjordes dels på processvatten från blekerierna och dels på avloppsvatten under reningsprocessen. Resultaten visar att den kemiska sammansättningen hos löst material har större inverkan på avloppsvattnets grad av nedbrytbarhet än den absoluta halten av syreförbrukande ämnen. En hög andel lignin ger ett mer svårnedbrytbart vatten. Suspenderat material är vidare mer svårnedbrytbart än de lösta fraktionerna. Analys av suspenderande substans hos blekpressat visar att andelen lignin är omkring 41 % medan arkiverade analysresultat på den lösta fasen visar ett innehåll på omkring 29 %. Det tyder alltså på en betydligt högre andel lignin i den partikulära fasen jämfört med den lösta, vilket i kombination med att materialet inte är lika lättillgängligt för mikroorganismerna kan förklara den låga bionedbrytbarheten. Om COD-utsläppet ska minskas bör inkommande flöde av löst lignin och suspenderande substans till den biologiska reningen reduceras. COD-halten i utgående avloppsvatten till recipienten utgörs av omkring 90 % lignin. De extraktivämnen som inte bryts ned är mättade fettsyror, exempelvis palmitin- och stearinsyra samt lignan, vilket antas bildas som restprodukt vid degradering av lignin. Flockning av syreförbrukande ämnen är ett sätt att gå till väga för att minska utsläppet av dessa till recipienten. Genom tillsats av 2,6 g/l PAX-18 (ett högladdat aluminiumkomplex) till blekeriavloppet kunde 40 % COD och 50 % lignin reduceras. Flockningsförsöket är gjort i laboratorieskala vid rumstemperatur och ytterligare utvärdering rekommenderas. Tidsstudier av BOD visar att mikroorganismerna behöver fem dagars uppehållstid för att hinna bryta ned organiskt material i avloppsvattnet, varför omloppstiden i den luftade lagunen inte bör understiga denna tidsrymd.
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Närsaltsdosering till luftad damm : en åtgärd för ökad TOC-reduktion hos Skoghalls Bruk luftade damm / Dosage of nutrient to an aerated lagoon : a measure to a higher TOC-reducation to the aerated lagoon of Skoghall MillBonde, Carl January 2006 (has links)
In the process of making carton boards into Skoghall Mill, are great quantities of water being contaminated. This water has to be treated before it is possible to release into the recipient, Kattfjorden. One of the contaminations that is important to extract from the wastewater, is organic carbon (measured as TOC-total organic carbon) because microbiological breakdown can lead to the bottom becomig free of oxygen. The wastewater treatment at Skoghall Mill is done through an external wastewater treatment that is located at the factory. The biological treatment (aerated lagoon) is a 140 000 m3 water pool with surface aerator, which is give oxygen to the water. In the lagoon live microorganisms who performs the biggest part of the TOC-reduction. One problem with the lagoon is that the treatment of TOC is considerably worse during wintertime than during summertime. The reduction is during wintertime only 40 %, while during summertime it is about 70-80 %. This seasonal variation can to a large extent be explained by, that the water temperature in the lagoon decreases wintertime. The low water temperature does that the biological activity in the lagoon is reduced, which reduces the TOC-reduction. A second reason can also be that the microorganisms do not have enough bioavailable nutrients that is needed for growth of a new biomass. In this thesis the need of nutrient has been examined. In two test pools, addings of nutrient were being done, to come to the conclusion of a good dosage of nutrient which would lead to a larger reduction of TOC, without enlarged quantities of nitrogen/phosphorus in the outgoing water. One of the test pools hold a summer temperature (30°C), and the other test pool hold a winter temperature (10°C). The test was performed this way to see if there would be any difference in the need of nutrient between summertime and wintertime. The most important conclusion was that a nutrient dosage to the Skoghall aerated lagoon, rise the TOC-reduction wintertime. It was also concluded that it was foremost the nitrogen that contributed to the raised TOC-reduction, and nitrogen is thereby considered to be the growth restraining element wintertime. It seemed like phosphorus had been overdosed during the tests, while enlarged halts of the substance could be seen in the outgoing water, and an optimal dosage of phosphorus could not be done. The recommendation that came as a results from the tests, was that during wintertime add nitrogen and phosphorus according to TOC:N:P-quota 100:0,75:0,10. To the summer pool was no considerable improvement of the TOC-reduction seen, as a result of the nutrient addings. It is also no reason to dosage nutrients in summertime. / Vid tillverkning av kartong och pappersmassa på Skoghalls Bruk förorenas stora mängder vatten, som därmed måste renas före utsläpp till recipienten, Kattfjorden, en vik i Vänern. En av de föroreningar som är viktig att avlägsna ur avloppsvattnet är organiska kolföreningar (TOC-total organic carbon) eftersom det vid mikrobiologisk nedbrytning av TOC åtgår syre vilket kan leda till att sjöbotten blir syrefri. Rening av avloppsvatten på Skoghall Bruk sker genom en extern reningsanläggning som är placerad på bruket. Det biologiska reningssteget i reningsanläggningen är en s.k. luftad damm. Detta är en 140 000 m3 stor vattenbassäng med ytluftare som syresätter vattnet. I dammen lever mikroorganismer vilka utför den största delen av TOC-reduktionen i brukets reningsanläggning. Ett problem med dammen är att reningen av TOC är betydligt sämre vintertid än sommartid. Reduktionen av det till dammen inkommande TOC, är vintertid endast ca 40 % medan den sommartid ligger kring 70-80 %. Denna årstidsvariation kan till stor del förklaras av att vattentemperaturen i dammen sjunker vintertid. Den låga temperaturen medför att den biologiska aktiviteten i dammen sjunker, vilket hämmar TOC-reduktionen. En annan orsak till en låg TOC-reduktion kan vara att det för mikroorganismerna råder brist på biotillgängliga närsalter (kväve och fosfor) som behövs för tillväxt av ny biomassa. I detta examensarbete har det undersökts behovet av närsalter för att höja TOC-reduktionen. I två laborationsdammar (ca 20 l) skedde doseringar av närsalter i syfte att finna en bra doseringskvot som innebar en ökad reduktion av TOC, utan att det blev förhöjda kväve-/fosforhalter i utgående vatten. En av laborationsdammarna höll sommartemperatur (ca 30°C) och en höll vintertemperatur (ca 10°C) vilket gjordes för att undersöka om det var skillnad av närsaltsbehovet mellan sommar och vintertid. Den viktigaste slutsatsen av försöken var att en närsaltsdosering till Skoghalls luftade damm höjer TOC-reduktion vintertid. Det konstaterades att det var kvävet som främst bidrog till den ökade TOC-reduktionen och kväve anses därmed vara det tillväxtbegränsande ämnet vintertid. Fosfor tycktes ha överdoserats under försöken, då det sågs förhöjda halter i utgående vatten, och en optimal dosering av fosfor kunde inte avgöras. Den rekommendation som föll ut av de laborativa försöken var att vintertid dosera kväve och fosfor enligt TOC:N:P-kvot 100:0,75:0,10. Till sommardammen sågs inte någon förbättring av TOC-reduktionen till följd av närsaltstillsatserna, vilket innebär att närsaltsdoseringar sommartid är obefogat. Vidare sågs tendenser till att slammets sedimentationsegenskaper, hos framförallt vinterdammen, blev bättre till följd av närsaltsdosering, men brist på mätdata medför att det är svårt att dra slutsatser om det verkligen varit så.
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A General Investigation of Shanghai Sewerage Treatment SystemChang, Jiang January 2011 (has links)
As a modern metropolis, Shanghai has a registered population of 18.8 million in 2011, and the permanent population has been more than 20 million. As a result, Shanghai produces more than 6.3 million cubic meters of sewage per day which is considered as a massive test for Shanghai’s sewerage treatment system. Given the high proportion of time spent on the literature review, this study has investigated how the whole system works in Shanghai. To do this, Shanghai sewerage systems were divided into two parts – the drainage system and the sewage treatment system, and they were introduced respectively following the track of history development process. It was done by combining previously published theses, study reports, governmental documents, overt information by companies and news reports. It showed that, in 2009, Shanghai’s government established a basic formation of six centralized sewage treatment systems in co-existence with 52 sewage treatment plants. In the same year, the sewage treatment rate reached 78.9%, which can be considered a leap compared with the 62.8% figure in 2003. In spite of that, the gap between sewage treatment in Shanghai and that in developed countries still exists. By comparing Shanghai Bai Longgang sewage treatment plant with Halmstad Västra Stranden's waste water treatment plant, it can be concluded that the gap was embodied in differences of inflow condition, relative low discharge standards and poor treatment capability.
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Raseinių rajono savivaldybės antropogeninės taršos mažėjimo prognozės / Anthropogenic pollution reduction prognosis in Raseiniai district municipalityPečkaitis, Martynas 08 August 2007 (has links)
Darbo tikslas yra įvertinti Raseinių rajono savivaldybės nuotekų sukeliamą taršą ir priemones jai mažinti. Raseinių rajone gyvena 43,7 tūkst. gyventojų, iš kurių apie 79 % prisijungę prie geriamojo vandens tiekimo ir apie 64 % - prie nuotekų šalinimo sistemos. Kiti individualūs gyventojai turi įsirengę vietinius nuotekų sukauptuvus arba turi vietinius nuotekų valymo įrenginius. Dėl blogos sukauptuvų priežiūros dažnai įvyksta persiliejimai, ir nevalytos nuotekos patenka į aplinką. Prieš 30-40 metų įrengtos centralizuotos nuotekų šalinimo sistemos rajone yra susidėvėjusios, todėl jose neišvengiama avarijų. Siekiant sumažinti avarijų, taršos židinių skaičių, būtina rekonstruoti senus vamzdynus, išplėsti nuotekų surinkimo tinklą, prijungiant kuo daugiau gyventojų prie centrinės nuotekų šalinimo sistemos. Vandentvarkos ūkio renovacija ir plėtra Raseinių rajone vykdoma Europos Sąjungos (ES) fondų, Lietuvos ir savivaldybės biudžetų lėšomis. Darbe nagrinėjama vandentvarkos ūkio būklė, ES fondų, Lietuvos ir Raseinių savivaldybės biudžeto remiamų priemonių įtaka aplinkosaugos būklei. / The purpose of this work is to evaluate the wastewater pollution in Raseiniai district and to sugest means to reduce it. Raseiniai district has a population of 43,7 thousand people. 79% of them are connected to the centralized drinking water system, and 64% of them use wastewater disposal system. The remaining individual householders usually use their own wastewater tanks or their local wastewater treatment equipment. Because of the poor wastewater system condition there are the leaks of wastewater to the environment. Since the wastewater treatment systems are 20 – 30 years old, a lot of happening accidents are inevitable. The old pipeline must be renovated in order to decrease the number of accidents and the sources of waste. In addition, more householders should be connected to the centralized wastewater system. The renovation and expansion of the Water – treatment network is financed from the budget of Raseiniai local administration, the structural funds of European Union(EU), and the Cohesion fund. The work includes the inspection of the current state of water-treatment network in Raseiniai district also the influence of the EU structural funds and other means which are used to improve the state of the environment.
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Επίδραση ελαιουργικών αποβλήτων στην επεξεργασία αστικών αποβλήτων με συστήματα ενεργού ιλύος - biocarriersΘεοδωρακόπουλος, Μάριος 07 October 2011 (has links)
Οι Μεσογειακές χώρες ετησίως, κατά την παραγωγή του ελαιολάδου,
έρχονται αντιμέτωπες με τη διαχείριση των υγρών αποβλήτων των ελαιοτριβείων, τα
οποία περιέχουν μεγάλες ποσότητες οργανικών ουσιών και αιωρούμενων στερεών,
προερχόμενα από τον καρπό και το χρησιμοποιούμενο νερό κατά τη μεταποιητική
διαδικασία. Η απόρριψή τους στο περιβάλλον ρυπαίνει υδροφόρους ορίζοντες και
επιφανειακά ύδατα, υποβαθμίζει το έδαφος, προκαλεί τοξικότητα και δυσάρεστη
οσμή. Πλήθος φυσικοχημικών, αλλά και βιολογικών μεθόδων έχουν δοκιμασθεί στην
προσπάθεια εξάλειψης των δυσμενών τους χαρακτηριστικών, χωρίς να έχουν δώσει
σε ευρεία κλίμακα λύση, προσκρούοντας κυρίως σε προβλήματα κόστους
εγκατάστασης και λειτουργίας καθώς και στη διακύμανση της σύστασης τους. Στόχος
της παρούσας έρευνας είναι η μελέτη της συμπεριφοράς των υγρών ελαιουργικών
λυμάτων κατά τη διοχέτευση τους σε μονάδα επεξεργασίας αστικών λυμάτων, ώστε
να είναι δυνατή η συνεπεξεργασία των δύο αυτών διαφορετικών ειδών λυμάτων και
να διερευνηθεί η δυνατότητα χρήσης ενός αντιδραστήρα ενεργού ιλύος με
προσροφητικό υλικό, PVA-gels Biocarriers. Δημιουργήθηκαν 6 αντιδραστήρες με
συγκεκριμένες αραιώσεις κατσίγαρου προς αστικά λύματα, σε συγκεντρώσεις ½, 1/10
και 1/100. Στο υπερκείμενο των συνθετικών λυμάτων πραγματοποιούνταν μετρήσεις
των φυσικοχημικών χαρακτηριστικών του ανεπεξέργαστου και επεξεργασμένου
συνθετικού λύματος περιοδικά έως το τέλος της πειραματικής διαδικασίας
(16/1/2011). Επίσης εξετάστηκε η μικροβιακή χλωρίδα του επεξεργασμένου
συνθετικού λύματος και η αποκατάστασή της. Παρατηρήθηκε ότι όλα τα συστήματα
επεξεργάζονταν ικανοποιητικά απόβλητα που περιείχαν ελαιουργικά λύματα σε
αναλογία 1/100 κατ’ όγκο, ότι η μικροβιακή τους χλωρίδα αποκαθίσταται, και θα
μπορούσαν να διατεθούν σε φυσικό αποδέκτη, ικανοποιώντας τα περισσότερα
κριτήρια της οδηγίας 91/271/ΕΕC. Στα συστήματα με αναλογία ½ και 1/10 κατ’ όγκο,
παρατηρήθηκε αξιόλογη επεξεργασία σε κάποιες παραμέτρους αλλά και πάλι ήταν
υψηλότερη από τα όρια διάθεσης. Τέλος, δεν παρατηρήθηκε κάποια αξιόλογη
διαφοροποίηση μεταξύ των δύο συστημάτων ενεργού ιλύος με και χωρίς Biocarriers,
τουλάχιστον για αυτό το πρώτο στάδιο εισαγωγής των Biocarriers. / Every year Mediterranean countries face the same problem of the olive oil mill
wastewater management. This type of wastewater contains high concentration of
organic loads and particulate suspended matter originating from the olives and the
production water. Dumping this kind of wastewater untreated to the environment
pollutes both surface and groundwater, degrades the soil quality and creates toxic
environments and unpleasant odors. Several physicochemical as well as biological
methods have been tested unsuccessfully due to the construction and operational costs
as well as the variability of the wastewater characteristics. The goal of the present
research is to study the behavior of the olive oil mill wastewater while it is introduced
in a municipal wastewater treatment plant. The use of PVA-gels as Biocarriers in
such a system is also tested. Six bioreactors were used with constant ratios of olive oil
mill wastewater to municipal wastewater equal to ½, 1/10, and 1/100. The
physicochemical parameters of the supernatant were measured periodically till the end
of the experiment (16/1/2011). In addition the microbial communities of the different
reactors were monitored especially after the return to the normal operation with
municipal wastewater. Both systems treat the olive oil mill wastewater mixed with
municipal wastewater in a ratio of 1/100 satisfactorily with outflow that could be
discarded to natural receiver being close to the requirements set by the European
directive 91/271/ΕΕC. Also, after the return to the normal operation with municipal
wastewater the microbial community was easily restored. In systems with such ratios
equal to ½ and 1/10, the treatment is effective but the outflow is high over the limits
set for municipal wastewater treatment plants. Finally, no significant deviation was
observed for activated sludge systems with and without Biocarriers for this initial
stage of Biocarriers introduction.
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Värmeåtervinning ur spillvatten för flerbostadshus : Kornstigen 25 i BorlängeMazraeh, Hifa, Abdullahi, Abdiaziz January 2018 (has links)
Syftet med detta arbete är att sammanställa kunskap om värmeåtervinningssystem för spillvatten i flerbostadshus från litteratur, tidigare studier och relevanta aktörer för ämnesområdet. Syftet är också att göra temperaturmätningar i ett flerbostadshus i Borlänge för att beräkna och analysera energibesparingspotential för Ekoflow värmeväxlaren från Isaksson Rostfria AB. Ekoflow är en spillvattenvärmeväxlare som återvinner värmeenergi ur spillvattnet. Genom spillvattenvärmeväxlare strömmas spillvattnet från avloppet och kallt vattnet i motströmriktningen. Ekoflow har monterats i vissa badhus och hotell och visade bra återvinningsgrader i dessa byggnader. Det är lite svårt att hitta en temperaturmätare på marknaden som kan mäta och lagra mätvärden på en vertikal avloppsstam, därför tillverkades en egen avloppstemperaturmätare som användes för att samla in mätdata för analysering och beräkning av avloppsvärmeförluster. Tillämpningen av tekniken i referensbyggnaden tillför vissa problem. ett problem är att både grå och svartvatten går igenom samma rör vilket minskar temperaturen för spillvattnet. Ett annat problem är att flerbostadshuset inte har någon gemensam anslutningspunkt till den kommunala avloppsledningen, vilket innebär att det kommer att behövas en avloppsvärmeväxlaren för varje stamledning. Energianvändningen i flerbostadshus varierar beroende på boarean och antal boende i huset. Antal boende i referensbyggnaden är inte känt men vattenflödets-och spillvattnets temperaturmätningar visade att byggnaden har hög varmvattenförbrukning. Energibesparingen är beroende av flera parametrar som inkommande kall- och spillvattentemperatur till spillvattenvärmeväxlare samt längden av värmeväxlaren. Energibesparingen för tre olika längder på Ekoflow värmeväxlaren beräknades och en 48 meters värmeväxlare visade energibesparing som ligger på ca. 40 MWh/år vilket motsvarar 24% av varmvattenbehovet i fastigheten. Detta förutsätter att avloppsledningarna kan sammankopplas till en gemensam anslutningspunkt i källarplanet. / The purpose of this work is to compile knowledge of waste water recovery systems in multi-family houses from literature, previous studies and relevant actors on the subject area. The purpose is also to make temperature measurements in a multi-family house in Borlänge to calculate and analyze the energy saving potential of the Ekoflow heat exchanger from Isaksson Rostfria AB. Ekoflow is a waste water heat exchanger that recycles heat energy from wastewater. Through wastewater heat exchanger, the waste water flows from the drain and the cold water in the countercurrent direction. Ekoflow has been installed in some bath houses and hotels and showed good recovery rates in these areas. It is a little difficult to find a temperature meter on the market that can measure and store the measured values of a vertical drainage stream. Therefore, produced own temperature meter, which was used to collect measurement data for analysis and calculation of the results. Application of the technology in the reference building adds some problems. One problem is that both gray and black water pass through the same pipe which reduces the temperature of the waste water. The second problem is that the building does not have a common connection point to the municipal sewers, which means that a heat exchanger will be needed for each main line. Energy consumption in multi-family houses varies depending on the living space and number of residents in the house. The number of residents in the reference building is not known but the temperature and water flow and spill water temperature measurements showed that the building has high hot water consumption. Energy saving depends on several parameters such as incoming cold and waste water temperature to waste water heat exchanger and the length of heat exchanger. The energy savings for three different lengths of the Ekoflow heat exchanger were calculated and a 48-meter heat exchanger showed energy savings of approximately 40 MWh / year, which is profitable from the energy saving perspective.
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