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Microfiltração tangencial como alternativa de pós-tratamento de efluente de reator anaeróbio de leito expandido alimentado com esgoto sanitário / Crossflow microfiltration as an alternative for advanced treatment of effluent of anaerobic reactor expanded bed feed with sewageVidal, Carlos Magno de Sousa 01 March 2001 (has links)
A constante exploração dos recursos hídricos para os mais diferentes usos sem um planejamento adequado, tem levado ao comprometimento desses recursos, verificando-se cada vez mais aumento no número de pesquisas e investimentos, visando o estudo de alternativas que viabilizem o tratamento avançado de águas residuárias e sua reutilização. Entre essas alternativas, estão as técnicas de separação dos materiais contaminantes por membranas. Neste trabalho estudou-se a viabilidade da utilização da microfiltração tangencial como alternativa de pós-tratamento de efluente de Reator Anaeróbio de Leito Expandido alimentado com esgoto sanitário, analisando-se a influência da utilização de cloreto férrico como coagulante, bem como, membranas com diferentes tamanhos de poro (0,2 e 1,0 μm), no desempenho da microfiltração tangencial. Os ensaios no sistema de microfiltração tangencial foram realizados em batelada, com amostras de efluente do reator anaeróbio de leito expandido (RALEX). Verificou-se que para os ensaios realizados com a membrana de 0,2 μm, o aumento das dosagens de cloreto férrico, contribuiu para diminuição nos valores de luxo de permeado. Esta relação não ocorreu de forma direta com a membrana de 1,0 μm. Os processos de coagulação e floculação foram essenciais para ambas membranas no aumento na eficiência de remoção da demanda química total de oxigênio (mg/l), fosfato total (mg P/l) e turbidez, no entanto, em relação aos valores de fluxo do permeado,foi prejudicial, pois nos ensaios em que as amostras de efluente do RALEX não foram previamente coaguladas e floculadas, a permeabilidade das membranas foi bem maios. O sistema de microfiltração tangencial operando com a membrana de 0,2 μm apresentou melhor desempenho, com valores de fluxo do permeado, em geral superiores a 100 L/m2.h, eficiência de 100% na remoção de coliformes totais e fecais, e a dosagem de 40 mg/l de cloreto férrico, já foi suficiente para uma eficiência média de remoção de DQOt de 95%; P.PO4-3 (89,5%) e Turbidez (96,4%). Portanto, a microfiltração tangencial pode ser considerada uma alternativa eficaz como unidade de pós-tratamento de efluente de reator anaeróbio de leito expandido, produzindo efluente que atende os padrões de reuso na agricultura, para coliforme totais e fecais. / The constant exploration of water resources for the most different uses, without an appropriate planning, has lead to the exhaustion of this resources. This scenery has showed the need of increasing researches and investments on alternative forms of wastewater treatment. This work studied the viability of using crossflow microfiltration as an alternative form of advanced treatment of effluents of Anaerobic Reactor Expanded Bed feed with sewage, examining the effect of the use of ferric chloride as coagulam, as well as of different pore size membranes (0,2 and 1,0 μm) on the performance of crossflow microfiltration. The experiments on crossflow microfiltration system were carried out in batch, using effluent samples of anaerobic reactor expanded bed. The results obtained with the 0,2 μm membrane showed that the increase of ferric chloride dosages contributed for the reduction on flux values. The 1,0 μm membrane did not presented this relation. The flocculation and coagulation processes were essentials for increasing the removal efficiency of Total Chemical Oxygen Demand, Total Phosphorus and Turbidity for both membranes, however, for the flux values the effect was harmful, because when the samples of the Anaerobic Reactor Expanded Bed were not previously coagulated and flocculated, the membranes penneability were higher. The Crossflow Microfiltration System, operating with the 0,2 μm membrane, presented better performance, with flux values generally superior than 100 L/m2.h, efficiency around 100% on the removal of Total and Fecal Coliforms. For this membrane (0,2 μm) the dosage of 40 mg/l of FeCl3 (first stage) was enough for an average of removal efficiency of Total Chemical Oxygen Demand (95%); Turbidity (96.4%); and P.PO4-3 (89,5%). Therefore, crossflow mocrofiltration can be considered an effective alternative for advanced treatment of effluents of Anaerobic Reactor Expanded Bed, producing a final effluent with large potentiality to be used in agriculture.
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Microfiltração tangencial como alternativa de pós-tratamento de efluente de reator anaeróbio de leito expandido alimentado com esgoto sanitário / Crossflow microfiltration as an alternative for advanced treatment of effluent of anaerobic reactor expanded bed feed with sewageCarlos Magno de Sousa Vidal 01 March 2001 (has links)
A constante exploração dos recursos hídricos para os mais diferentes usos sem um planejamento adequado, tem levado ao comprometimento desses recursos, verificando-se cada vez mais aumento no número de pesquisas e investimentos, visando o estudo de alternativas que viabilizem o tratamento avançado de águas residuárias e sua reutilização. Entre essas alternativas, estão as técnicas de separação dos materiais contaminantes por membranas. Neste trabalho estudou-se a viabilidade da utilização da microfiltração tangencial como alternativa de pós-tratamento de efluente de Reator Anaeróbio de Leito Expandido alimentado com esgoto sanitário, analisando-se a influência da utilização de cloreto férrico como coagulante, bem como, membranas com diferentes tamanhos de poro (0,2 e 1,0 μm), no desempenho da microfiltração tangencial. Os ensaios no sistema de microfiltração tangencial foram realizados em batelada, com amostras de efluente do reator anaeróbio de leito expandido (RALEX). Verificou-se que para os ensaios realizados com a membrana de 0,2 μm, o aumento das dosagens de cloreto férrico, contribuiu para diminuição nos valores de luxo de permeado. Esta relação não ocorreu de forma direta com a membrana de 1,0 μm. Os processos de coagulação e floculação foram essenciais para ambas membranas no aumento na eficiência de remoção da demanda química total de oxigênio (mg/l), fosfato total (mg P/l) e turbidez, no entanto, em relação aos valores de fluxo do permeado,foi prejudicial, pois nos ensaios em que as amostras de efluente do RALEX não foram previamente coaguladas e floculadas, a permeabilidade das membranas foi bem maios. O sistema de microfiltração tangencial operando com a membrana de 0,2 μm apresentou melhor desempenho, com valores de fluxo do permeado, em geral superiores a 100 L/m2.h, eficiência de 100% na remoção de coliformes totais e fecais, e a dosagem de 40 mg/l de cloreto férrico, já foi suficiente para uma eficiência média de remoção de DQOt de 95%; P.PO4-3 (89,5%) e Turbidez (96,4%). Portanto, a microfiltração tangencial pode ser considerada uma alternativa eficaz como unidade de pós-tratamento de efluente de reator anaeróbio de leito expandido, produzindo efluente que atende os padrões de reuso na agricultura, para coliforme totais e fecais. / The constant exploration of water resources for the most different uses, without an appropriate planning, has lead to the exhaustion of this resources. This scenery has showed the need of increasing researches and investments on alternative forms of wastewater treatment. This work studied the viability of using crossflow microfiltration as an alternative form of advanced treatment of effluents of Anaerobic Reactor Expanded Bed feed with sewage, examining the effect of the use of ferric chloride as coagulam, as well as of different pore size membranes (0,2 and 1,0 μm) on the performance of crossflow microfiltration. The experiments on crossflow microfiltration system were carried out in batch, using effluent samples of anaerobic reactor expanded bed. The results obtained with the 0,2 μm membrane showed that the increase of ferric chloride dosages contributed for the reduction on flux values. The 1,0 μm membrane did not presented this relation. The flocculation and coagulation processes were essentials for increasing the removal efficiency of Total Chemical Oxygen Demand, Total Phosphorus and Turbidity for both membranes, however, for the flux values the effect was harmful, because when the samples of the Anaerobic Reactor Expanded Bed were not previously coagulated and flocculated, the membranes penneability were higher. The Crossflow Microfiltration System, operating with the 0,2 μm membrane, presented better performance, with flux values generally superior than 100 L/m2.h, efficiency around 100% on the removal of Total and Fecal Coliforms. For this membrane (0,2 μm) the dosage of 40 mg/l of FeCl3 (first stage) was enough for an average of removal efficiency of Total Chemical Oxygen Demand (95%); Turbidity (96.4%); and P.PO4-3 (89,5%). Therefore, crossflow mocrofiltration can be considered an effective alternative for advanced treatment of effluents of Anaerobic Reactor Expanded Bed, producing a final effluent with large potentiality to be used in agriculture.
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Optimisation of an ultrafiltration unit on a bench-scale pilot plant - A comparison between carbon and sand filtrate / Optimering av en UF-mikropilot – Jämförelse av kol- och sandfiltratWarman, Philip January 2022 (has links)
Kommunalförbundet Norrvatten är en av Sveriges största producenter av dricksvatten och förser över 50 miljoner vatten till över 700 000 invånare i norra Stockholm. Vattnet är renat i Görvälnverket som har sedan år 2016 planlagt en expansion av verkets kapacitet och kvalité. Ett fokusområde för att förbättra reningsprocessen är implementering av membranteknik. I det här projektet har experiment utförts som ett fortsatt arbete av att integrera ultrafiltration med koagulering på en mikropilot. Syftet med projektet är att optimera driftparameterar (koaguleringsdos, pH och alkalitet, uppehållstid och omblandning) för processen och jämföra pilotens effektivitet för två typer av matarvatten (kol- och sandfiltrat). En lägre koaguleringsdos på 2.5 mg Al/L resulterade i en 18.9 % avskiljning av TOC och 21.3% minskning i UV254. I jämförelse med en högre dos på 3.8 mg Al/L, var effektiviteten 2 % bättre för TOC och 3 % bättre för UV254. Till följd av en låg ökning i effektivitet för en högre koagulantdos påvisar en lägre dosering ett bättre alternativ. Dessutom är det rekommenderat att vid uppskalandet av piloten mer försök genomförs för att få mer pålitliga data och att automatisk dosering implementeras eftersom dosering av koagulant var en svårkontrollerad parameter.pH inom intervallet 6.8 till 7.2 visade vara mest optimal för att minimera mängden aluminiumrester i permeatet. Experimenten på pH konstaterar att flockning är pH beroende och optimalt vid pH 7. Effektiviteten var också beroende av alkaliteten. Där bäst alkalinitet anpassades till mellan 40 och 50 mg HCO3/L, med högre än 50 mg HCO3/L minskade effektiviteten av avskiljningen, vilket tyder på sämre flockning vid basiska förhållanden. Karbonatdosering av 5 mL 0.01 M Na2CO3 /L obehandlat vatten uppnådde önskad alkalinitet och minimerade aluminiumrester i permeatet. Uppehållstiden och konfigurationen av blandning indikerade ingen optimal justering. Emellertid, en jämförelse av försök med uppehållstiden och försök utan koaguleringdos visade dramatisk minskning i effektivitet till endast 2 % TOC avskiljning och 6 % UV254 minskning. Placering av ultrafiltrationsenheten efter kolfiltret jämfört med efter sandfiltret visade inga tecken på nedsatt effektivitet. Transmembrantrycket över membranet ökade över den experimenterade perioden från 0.02 till 0.06 bar och fluktuerade under drift mellan det första och sista försöket. Det var däremot ingen skillnad i trycket mellan kolfilter och sandfilter, vilket styrker beslutet att placera ultrafiltrationsenheten efter kolfiltret. / The municipal association Norrvatten is one of Sweden's largest drinking water producers and distributes over 50 million m3 of drinking water to around 700 000 inhabitants in northern Stockholm. The water is treated in the Görväln plant, which has since 2016 planned to expand its capacity and improve its water quality. One researched area for improving the treatment process is implementing membrane technology. In this project, experiments are performed as a continued work of integrating ultrafiltration with coagulation on a bench-scale plant. The purpose is to optimise the operating parameters (coagulant dosage, pH & alkalinity, retention time, and mixing) and compare the ultrafiltration removal efficiency for two types of feed water (carbon and sand filtrate). A lower coagulant dosage of 2.5 mg Al/L resulted in removal efficiencies on average of 18.9 % TOC removal and 21.3 % UV254 reduction. Compared to the higher dosage of 3.8 mg Al/L, the removal efficiency was only decreased with 2 % TOC and 3 % UV254. Therefore, a lower dosage is a more suitable option. Although, more data needs to be collected for a more reliable optimal dosage. In addition, for the up-scaling of the pilot, automatic dosage control needs to be implemented as the coagulant dosage is difficult to control as a parameter. pH showed the best removal efficiency in the range of 6.8 to 7.2 and minimised aluminium residue in the permeate. It verifies that flock formation is pH-dependent and optimal close to 7. The efficiency also depended on the alkalinity, with the optimal alkalinity between 40 to 50 mg HCO3/L. Higher alkalinity decreased the efficiency, which supports the theory that too basic water hinders flock formation. With minimum dosage of 5 mL 0.01 M Na2CO3/L untreated water, the required alkalinity could be achieved without affecting the amount of aluminium in the permeate residue. The retention time and mixing configuration did not result in an optimum adjustment. However, with no retention time at a coagulant dosage of 0 mg Al/mL, the efficiency was reduced drastically to 2 % TOC removal and 6 % UV254 reduction. The placement after the carbon filter showed no adverse signs on the removal efficiency compared with placing it after the sand filter. The TMP of the membrane increased over time from 0.02 to 0.06 bar, and higher fluctuations in TMP were noted in the last experiment compared to the first. The differences were identical for both carbon and sand filtrate, strengthening the decision to place the ultrafiltration unit after the carbon filter.
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Improving Wastewater Treatment and Management: A case study on a Combined Heat and Power Plant in Sweden / Förbättring av dag- och processvattenrening och hantering: En fallstudie på ett kraftvärmeverk i SverigeThunholm, Sara January 2024 (has links)
Vatten är en av de viktigaste resurserna för mänskligheten eftersom det är en nödvändighet för överlevnad men också en viktig faktor inom många industrier. Utöver detta är vattenförorening ett globalt problem som påverkar både miljön och människors hälsa. Många länder runt om i världen saknar fortfarande en hållbar vattenhantering inom många sektorer, varav en viktig är energiproduktionssektorn. Detta problem hotar inte bara mål 6: rent vatten och sanitet för alla, utan även fler av FNs globala mål. Händelöverket är ett stort kraftvärmeverk som har levererat fjärrvärme till Norrköping sedan 1982. Sedan dess har anläggningen utökats från två till fem pannor. För att säkerställa en kontinuerlig tillförsel av bränsle har bränslelagret utökats och är nu fyllt med bränslen som exempelvis träflis, gummi, återvunnet trä, kol och avfall. En ökad produktionskapacitet har även lett till en ökad mängd dag- och processvatten som måste behandlas. Ursprungligen byggdes en sedimenteringsbassäng för att behandla avloppsvatten från de två första pannorna. Idag används samma bassäng för att behandla allt dagvatten och processvatten från hela Händelöverkets område tillsammans med två efterföljande sandfilter. Syftet med denna studie var att undersöka möjliga förbättringar av vattenreningen av dagvatten och processvatten vid Händelöverket. Studien begränsades till att fokusera på två vattenströmmar, en som består av dagvatten från bränslelagret och en annan som är ansluten till den strömmen och samlar upp avrinningsvatten från avfallet i bunkern. Dessutom karakteriserades dessa avfallsströmmar med avseende på koncentration av metaller, kemisk syreförbrukning, biologisk syreförbrukning (7 dagar), suspenderade partiklar och pH. Baserat på resultaten presenterades tre olika förbättringsalternativ. Från Case 1 drogs slutsatsen att återcirkulering av avrinningsvatten från avfallet tillbaka in i bunkern var ett enkelt och ekonomiskt genomförbart alternativ. Dessutom skulle det resultera i en vattenhantering som är bättre anpassat till slutsatserna i Best Available Technology presenterat av Europeiska unionen. Dessutom skulle Case 1 inte heller påverka pannornas effektivitet väsentligt. Case 2 föreslog en förändring i hanteringsplanen för hanteringen av släckvatten om en brand skulle uppstå på bränsleytan eller i avfallet i bunkern. Från Case 2 drogs slutsatsen att denna plan bör förbättras genom att införa ytterligare bestämmelser om att leda släckvatten till den befintliga bergrumsvattenreningen som applicerar fällnings- och flockningsteknik. Slutligen fokuserade Case 3 på förbättringar som skulle kunna göras för att öka effektiviteten av behandling av zink, koppar, nickel och bly. Från dessa case drogs slutsatsen att implementering av en polymerblandare samt att flytta doseringsplatsen längre upp i sedimenteringssbassängen skulle vara det mest lämpliga första steget. Dessutom rekommenderades det också att installera ett fällningssteg före polymerdoseringen för att fälla ut metaller som fortfarande är i lösning och därmed öka renlighetsgraden ytterligare i processen. / Water is one of the most important resources for humanity as it is a necessity for survival but also an important factor within many industries. In addition to this, water pollution is a global concern affecting both the environment and human health. Many countries around the world still lack a sustainable water management within many sectors whereas one important one is energy production. This problem threatens not only goal 6: clean water and sanitation, but also many other of the sustainable development goals presented by the united nations development programme. Händelöverket is a large combined heat and power plant supplying the city of Norrköping with district heating since 1982. Since then the plant has expanded from two to five boilers in operation. Additionally, to have a continuous supply of fuel, the storage area has been increased and is now filled with fuels like wood chips, rubber tires, recycled wood, coal and waste. An expanding production site has naturally led to an increased amount of storm- and process water that has to be treated. Originally a sedimentation was built to only treat waste water from two boilers. Today the same basin is used to treat all storm and process water from the entire site of Händelöverket together with the following sand filters. The scope of this study was to investigate potential improvements of the waste water treatment of the storm- and process water treatment at Händelöverket. This study focused on two waste water streams: one consisting of storm water from the fuel yard, and stream another connected to it, which collects waste leachate water. Furthermore these waste flows were characterized in terms of metal concentration, chemical oxygen demand, biological oxygen demand, total suspended solids and pH. Based on the results, three different cases of improvements were presented. Case 1 concluded that recirculating of the waste leachate water back onto the waste material was a simple and economically feasible option. Furthermore it would result in a waste water management more aligned with Best available technology regulation presented by the European Union. Additionally it would not significantly effect the efficiency of the boilers. Case 2 proposed a change in the management plan for handling extinguishing water if a fire would occur on the fuel yard or within the waste material of the bunker. It was concluded that this plan should be improved to send water of similar quality to the other existing waste water treatment plant working with a coagulation and flocculation technique. Lastly Case 3 focused on improvements that could be made to the existing storm and process wastewater treatment process that could enhance the efficiency of treating zinc, copper, nickel and lead. It was concluded that implementing a polymer mixing tank and moving the dosing locationfurther up the sedimentation basin would be the most important first step. Furthermore it was also recommended to install a precipitation step before the polymer dosing to precipitate metals that are still in solution. By doing this the degree of purification will be increased further for the storm- and process water treatment.
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