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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

Numerisk förstudie av industriell symbios mellan fiskodling och pappers och massaindustrin : Med fokus på möjligheter och begränsningar / Numerical feasibility study of industrial symbiosis between fish farming and the paper and pulp industry : With a focus on opportunities and limitations

Meldgaard, Susanna January 2022 (has links)
I många år har linjär ekonomi tillämpats i samhället men det börjar ske en förändring. Nu börjar det bli intressant att skapa ett ekonomiskt värde i restprodukter genom att bilda cirkulära ekonomier, som dessutom minskar utarmningen av jordens resurser och skapar hållbarhet. En kritisk ändlig naturresurs för alla levande organismer är mackronäringsämnet fosfor. Den bryts i stora dagbrott men börjar bli mer svåråtkomlig och utspädd vilket kan leda till att det blir en resursbrist i framtiden. De skogsindustriella reningsverken behöver näringsämnen för att kunna rena avloppsvatten från organiskt material. Där tillsätts bland annat kväve och fosfor vars utvinning är energikrävande och bidrar till miljöföroreningar. Inne i reningsverket sker många biologiska processer som är beroende av flera faktorer för att uppnå en hög reningsgrad. En faktor är temperatur. Pappers och massabruken har ofta varma flöden som behöver kylas ner innan de går till reningsverket, därav fås ett stort överskott av lågvärdig energi som ej används (spillvärme). Under de senaste åren har både ett politiskt och privat driv uppstått att utöka det svenska vattenbruket med akvatiska produkter, exempelvis fisk. Fiskar kan odlas i öppna kassar i sjöar/hav men det finns risker så som övergödning och spridning av sjukdomar. Därav är intresset stort för landbaserade fiskodlingar med Recirculating Aquaculture Systems. En landbaserad fiskodling har dock ett stort värmebehov för att bibehålla rätt vattentemperatur för fisken. Avloppsvattnet har även ett högt innehåll av kväve och fosfor som behöver renas innan det släpps ut. Med hjälp av programmet Simulink byggdes en simuleringsmodell över ett skogsindustriellt reningsverk i symbios med en fiskodling. Syftet var att undersöka möjligheter och begränsningar för symbiosen med ett extra fokus på reningsverket. Målen var att ta reda på hur mycket mindre kväve och fosfor som behövs i reningsverket, utföra en miljöanalys av symbiosen, identifiera begränsande faktorer och hitta lösningar samt ta reda på om spillvärmen räcker för att värma fiskodlingen De erhållna resultaten var att reningsverket kan spara 82 ton fosforsyra och upp till 817 ton ammoniak per år. Reningsverket klarar belastningen från en fiskodling med en årlig produktion på 2200 ton fisk utan överskrida sin dåvarande utsläpp år 2021, vilket motsvarar 2,9 kg odlad fisk per ton producerad massa. Det kan reducera reningsverkets och fiskodlingen koldioxidutsläpp med 471,1 ton respektive 485,7 ton per år. Under året infaller ett processtop i pappers och massaindustrin. Det leder till strypt värmetillförsel för fiskodlingen som resulterar i för kall fiskvattentemperatur samt för höga utsläpp närsalter vid uppstart av reningsverket. En lösning är att lägga på fem centimeters isolering på fiskpoolerna. För att minimera närsaltsutsläppen kan fasta närsalter ur fiskavloppsvattnet filtreras bort och en kolkälla tillsättas. För att maximera användningen av spillvärme kan en icke isolerad 3000 ton fiskodling byggas. Värmningsbehovet per år blir då runt 16000 MWh vilket motsvarar cirka 4,7 % av spillvärmen. / For many years, linear economics has been applied in society, but it is changing. Instead, it is now interesting to create an economic value in residual products by forming circular economies, which also reduces the depletion of the earth's resources and promote sustainability. A critical finite natural resources for all living organisms is the macronutrient phosphorus. It is mined in large open pits but is becoming diluted and difficult to access, which may lead to a lack of resource in the future. The forest industry wastewater treatment plants need nutrients to be able to treat wastewater from organic material. Among other things, nitrogen and phosphorus are added, the extraction of which is energy-intensive and contributes to environmental pollution. Inside the treatment plant, many biological processes take place that depend on several factors to achieve a high degree of treatment. One factor is temperature. Paper and pulp mills often have warm streams of water that needs to be cooled down before being sent to the treatment plant, which results in a large surplus of waste heat that is not used. In recent years, both a political and private drive has arisen to expand Swedish aquaculture with aquatic products such as fish. Fish can be grown in open net pens in lakes / seas, but there are risks such as eutrophication and the spread of diseases. As a result, there is great interest in land-based fish farms with Recirculating Aquaculture Systems. However, a land-based fish farm has a great need for heat to maintain the right water temperature for the fish. The wastewater also has a high content of nitrogen and phosphorus that needs to be treated before it is discharged. With the help of the program Simulink, a simulation model was built describing a forest industry treatment plant in symbiosis with a fish farm. The purpose was to investigate possibilities and limitations for the symbiosis with an extra focus on the treatment plant. The goals were to investigate how much less nitrogen and phosphorus is needed in the treatment plant, perform an environmental analysis of the symbiosis, identify limiting factors, find solutions and find out if there is enough waste heat to heat the fish farm The results obtained were that the treatment plant can save 82 tonnes of phosphoric acid and up to 817 tonnes of ammonia per year. The treatment plant manages the load from a fish farm with an annual production of 2200 tonnes of fish without exceeding its equivalent discharge pollution levels of 2021, which is equal to 2,9 kg farmed fish per tonne produced pulp. It can reduce the treatment plant's and fish farm's carbon dioxide emissions by 471.1 tonnes and 485.7 tonnes per year, respectively During the year, a process stop occurs in the paper and pulp industry. This leads to a restricted heat supply for the fish farm, which results in a too cold water temperature for the fish and too high discharges of nutrients in to receiving lake at the start-up of the treatment plant. One solution to this issue is to put five centimetres of insulation on the fish pools. To minimize nutrient discharges, the solid nutrients from the fish wastewater can be filtered out and a carbon source added. To maximize the use of waste heat, a non-insulated 3000 ton fish farm can be built. The heating demand per year will then be around 16,000 MWh, which corresponds to approximately 4.7% of the waste heat.
92

Urban Rain Water Harvesting and Water Management in Sri Lanka

Strand, Anders January 2013 (has links)
Denna fältstudie kommer att undersöka betydelsen av regnvattenanvändning som vattenförsörjnings alternativ. Hur kan hållbara innovativa lösningar tas fram för att lösa vattenförsörjningen på Sri Lanka? Efter lidandet av mer än 30 års inbördeskrig och efter de omfattande skadorna från tsunamin 2004, står nu Sri Lanka inför många utmaningar rörande landets återuppbyggnad. Tillgången till vatten är den viktigaste grundläggande förutsättningen för ett fungerande samhälle. I landets torra zon är det långa perioder av torka då vattenkällor sinar och inget naturligt vatten finns att tillgå. Detta trots att det under monsunen kommer tillräckligt med regn för att täcka vattenbehovet om det skulle samlas på ett optimalt sätt. Avrinningskoefficienten är här mer än 60% outnyttjat regnvatten. I ett flertal lyckade projekt har man samlat regnvatten i RWH system för senare användning. Människor i dessa områden saknar kranvatten eftersom detta område ej är täckt av vattenförsörjningsnätet. Detta gör att dessa människor har en positiv inställning till att ha RWH system..I den våta zonen, och då speciellt i Colombos stadsmiljö som denna studie handlar om, är situationen annorlunda. Här har de flesta invånare kranvatten. Det kommunala kranvattnet är högt subventionerat av regeringen vilket gör att kostnaden är låg för användarna samt ökar vattenkonsumtionen. Invånarna känner inget ansvar för vattenresurserna eftersom den gemena uppfattningen är att det är en evig källa. Majoriteten av hushållen ser inget skäl till att installera RWH på grund av den låga lönsamheten. Trots att det finns ett förordnande att det ska ingå ett RWH system, så följs inte detta. Saknande av uppföljningsplikt anges som orsak av vatten styrelsen. Kostnaden för att behandla och leverera vatten till invånarna är väldigt hög och är mycket energi krävande. Det finns ett behov av enorma investeringar för att rusta upp och bygga ut både vattenverken och vattennätet för att klara av att möta det växande invånarantalet i Colombo området. Ett annat problem är att 40% av hushållen i Colombo saknar avloppsanslutning. De leder sitt avloppsvatten direkt eller efter en septi-tank ut i jorden eller havet.Om medvetenheten kring dessa frågor ökar, samt att förhållandet mellan kranvattnets kostnad och RWH justeras med ändringar i subventionerna, kunde en hållbar lösning på vattensituationen med såväl ekonomiska som miljövinster ske.Resultatet av denna studie är att RWH får ses som ett komplement när det gäller vattenförsörjningen för hushållens del. Fokus bör istället ligga på industrier, sjukhus, skolor, kommunala byggnader och andra byggnader med stora vattenbehov och med de största möjligheterna att uppnå optimalt resultat.Studien visar också på en hållbar lösning på avloppshanteringen. Den visar DWWT och dess fördelar. / The field study will investigate the importance of Rain Water Harvesting (RWH) as a water supply option. How can sustainable innovative solutions be developed to solve the water problem of Sri Lanka? Suffering from more than 30 years of civil war and damages after being struck by the tsunami 2004, Sri Lanka faces many challenges to recover and rebuilt the country. The access to water is the most important need for a civilization´s existence. In the dry zones of the island people suffer from long drought periods with dried up wells and no natural sources for water. However the rainfall during the monsoon, even in these areas, is more than enough to provide the water needs if properly collected, thus the run-off coefficient is more than 60%. Several projects with rain water harvesting in so called RWH systems have been implemented with success. Because these areas are not covered by the water supply net and therefore have no tap water, the people are very positive to having the RWH system. In the wet zones and especially in the urban environment of Colombo the situation is different. Here most of the people have treated pipe-borne tap water. The metered tap water is highly subsidized by the government which makes the cost low for the users and increases the water consumption. The citizens do not feel a responsibility to be careful with resources since the common opinion is that water is a never ending source. The majority of the households find no reasons for installing a RWH system because it´s low economic profits. Even if there is a legislation that demands all new buildings should have a RWH system not many households have installed these systems. However the cost to deliver and treat this water is very expensive for the government and demands a lot of energy. Huge investments need to be done in both the treatment plants and the pipe-line net to meet the growing population in Colombo area. Another problem is that 40% of the households today in Colombo have no sewage connection but lead their wastewater directly or after a septic tank into the ground or the sea. If the awareness regarding these concerns could be improved and the conditions between tap water costs and RWH be adjusted with changes in the subsidized system, a sustainable solution to the water situation in Colombo with both economic and environmental benefits could be found. The result from the case study is a recommendation about installing RWH as a complimentary source of water for the households. And investments in RWH systems should be focused to industries, hospitals, schools, municipal buildings and other public buildings with a high water demand and with the best possibilities for optimal results. Further the case study treats a sustainable solution to the sewage situation. It shows the Decentralized waste water treatment plant (DWWT) and its advantages.
93

Drinking water treatment sludge production and dewaterabilityф

Verrelli, D. I. January 2008 (has links)
The provision of clean drinking water typically involves treatment processes to remove contaminants. The conventional process involves coagulation with hydrolysing metal salts, typically of aluminium (‘alum’) or trivalent iron (‘ferric’). Along with the product water this also produces a waste by-product, or sludge. The fact of increasing sludge production — due to higher levels of treatment and greater volume of water supply — conflicts with modern demands for environmental best practice, leading to higher financial costs. A further issue is the significant quantity of water that is held up in the sludge, and wasted. / One means of dealing with these problems is to dewater the sludge further. This reduces the volume of waste to be disposed of. The consistency is also improved (e.g. for the purpose of landfilling). And a significant amount of water can be recovered. The efficiency, and efficacy, of this process depends on the dewaterability of the sludge.In fact, good dewaterability is vital to the operation of conventional drinking water treatment plants (WTP’s). The usual process of separating the particulates, formed from a blend of contaminants and coagulated precipitate, relies on ‘clarification’ and ‘thickening’, which are essentially settling operations of solid–liquid separation.WTP operators — and researchers — do attempt to measure sludge dewaterability, but usually rely on empirical characterisation techniques that do not tell the full story and can even mislead. Understanding of the physical and chemical nature of the sludge is also surprisingly rudimentary, considering the long history of these processes. / The present work begins by reviewing the current state of knowledge on raw water and sludge composition, with special focus on solid aluminium and iron phases and on fractal aggregate structure. Next the theory of dewatering is examined, with the adopted phenomenological theory contrasted with empirical techniques and other theories.The foundation for subsequent analyses is laid by experimental work which establishes the solid phase density of WTP sludges. Additionally, alum sludges are found to contain pseudoböhmite, while 2-line ferrihydrite and goethite are identified in ferric sludges. / A key hypothesis is that dewaterability is partly determined by the treatment conditions. To investigate this, numerous WTP sludges were studied that had been generated under diverse conditions: some plant samples were obtained, and the remainder were generated in the laboratory (results were consistent). Dewaterability was characterised for each sludge in concentration ranges relevant to settling, centrifugation and filtration using models developed by LANDMAN and WHITE inter alia; it is expressed in terms of both equilibrium and kinetic parameters, py(φ) and R(φ) respectively.This work confirmed that dewaterability is significantly influenced by treatment conditions.The strongest correlations were observed when varying coagulation pH and coagulant dose. At high doses precipitated coagulant controls the sludge behaviour, and dewaterability is poor. Dewaterability deteriorates as pH is increased for high-dose alum sludges; other sludges are less sensitive to pH. These findings can be linked to the faster coagulation dynamics prevailing at high coagulant and alkali dose.Alum and ferric sludges in general had comparable dewaterabilities, and the characteristics of a magnesium sludge were similar too.Small effects on dewaterability were observed in response to variations in raw water organic content and shearing. Polymer flocculation and conditioning appeared mainly to affect dewaterability at low sludge concentrations. Ageing did not produce clear changes in dewaterability.Dense, compact particles are known to dewater better than ‘fluffy’ aggregates or flocs usually encountered in drinking water treatment. This explains the superior dewaterability of a sludge containing powdered activated carbon (PAC). Even greater improvements were observed following a cycle of sludge freezing and thawing for a wide range of WTP sludges. / Further aspects considered in the present work include deviations from simplifying assumptions that are usually made. Specifically: investigation of long-time dewatering behaviour, wall effects, non-isotropic stresses, and reversibility of dewatering (or ‘elasticity’).Several other results and conclusions, of both theoretical and experimental nature, are presented on topics of subsidiary or peripheral interest that are nonetheless important for establishing a reliable basis for research in this area. / This work has proposed links between industrial drinking water coagulation conditions, sludge dewaterability from settling to filtration, and the microstructure of the aggregates making up that sludge. This information can be used when considering the operation or design of a WTP in order to optimise sludge dewaterability, within the constraints of producing drinking water of acceptable quality.
94

Variabilidade Climática, Disponibilidade Hídrica e ETA Guandu: Uma Análise Qualitativa de Vulnerabilidade. / Climate variability, water availability and Guandus water treatment plant: a quantitative analysis of vulnerability.

Maria Augusta Roberto Braga Nogueira 05 April 2012 (has links)
A ETA Guandu é de vital importância para o estado do Rio de Janeiro por ser responsável pelo abastecimento de 8,5 milhões de pessoas na Região Metropolitana. Este trabalho tem como objetivo efetuar uma análise qualitativa de sua vulnerabilidade, em relação à qualidade e quantidade de água captada, perante diversos fatores de estresse, visando dimensionar a importância da variabilidade climática na composição de sua vulnerabilidade. Adotou-se o conceito de vulnerabilidade como função da exposição (grau em que um sistema experimenta estresses), da sensibilidade (grau em que um sistema é afetado pelo estresse) e capacidade adaptativa (capacidade de um sistema de se ajustar, moderar ou lidar com as conseqüências de um estresse). Dessa forma, foi possível desenvolver uma metodologia de análise qualitativa de vulnerabilidade, específica ao caso da ETA Guandu, perante quatro fatores de estresse considerados como os mais determinantes para a vulnerabilidade atual: i) variabilidade climática; ii) transposição; iii) condições ambientais e qualidade da água e iv) acidentes ambientais. Os resultados evidenciaram que o maior grau de vulnerabilidade da ETA Guandu se relaciona à transposição, já que diversas partes de sua infraestrutura não dispõem de ações de manutenção preventiva. A vulnerabilidade devido às condições ambientais é também intensa, principalmente a turbidez no período chuvoso; entre 2000 e 2010, a ETA Guandu foi parcialmente paralisada 22 vezes em função do grande aporte de sedimentos. Não identificamos nenhum registro de paralisação total da ETA Guandu em função de acidentes ambientais, embora algumas vezes estes tenham imposto a paralisação da transposição. O componente variabilidade climática (intensificação de eventos hidrológicos extremos) revelou-se como o estressor menos determinante da vulnerabilidade atual.
95

Variabilidade Climática, Disponibilidade Hídrica e ETA Guandu: Uma Análise Qualitativa de Vulnerabilidade. / Climate variability, water availability and Guandus water treatment plant: a quantitative analysis of vulnerability.

Maria Augusta Roberto Braga Nogueira 05 April 2012 (has links)
A ETA Guandu é de vital importância para o estado do Rio de Janeiro por ser responsável pelo abastecimento de 8,5 milhões de pessoas na Região Metropolitana. Este trabalho tem como objetivo efetuar uma análise qualitativa de sua vulnerabilidade, em relação à qualidade e quantidade de água captada, perante diversos fatores de estresse, visando dimensionar a importância da variabilidade climática na composição de sua vulnerabilidade. Adotou-se o conceito de vulnerabilidade como função da exposição (grau em que um sistema experimenta estresses), da sensibilidade (grau em que um sistema é afetado pelo estresse) e capacidade adaptativa (capacidade de um sistema de se ajustar, moderar ou lidar com as conseqüências de um estresse). Dessa forma, foi possível desenvolver uma metodologia de análise qualitativa de vulnerabilidade, específica ao caso da ETA Guandu, perante quatro fatores de estresse considerados como os mais determinantes para a vulnerabilidade atual: i) variabilidade climática; ii) transposição; iii) condições ambientais e qualidade da água e iv) acidentes ambientais. Os resultados evidenciaram que o maior grau de vulnerabilidade da ETA Guandu se relaciona à transposição, já que diversas partes de sua infraestrutura não dispõem de ações de manutenção preventiva. A vulnerabilidade devido às condições ambientais é também intensa, principalmente a turbidez no período chuvoso; entre 2000 e 2010, a ETA Guandu foi parcialmente paralisada 22 vezes em função do grande aporte de sedimentos. Não identificamos nenhum registro de paralisação total da ETA Guandu em função de acidentes ambientais, embora algumas vezes estes tenham imposto a paralisação da transposição. O componente variabilidade climática (intensificação de eventos hidrológicos extremos) revelou-se como o estressor menos determinante da vulnerabilidade atual.
96

Estudo de influência de cobertura plástica na remoção de água de lodos de estações de tratamento de água em leitos de drenagem

Reis, Renan Felicio dos 23 March 2011 (has links)
Made available in DSpace on 2016-06-02T20:00:37Z (GMT). No. of bitstreams: 1 3585.pdf: 4834479 bytes, checksum: 5a0924e0311d45a52820620dbafa4f6a (MD5) Previous issue date: 2011-03-23 / Universidade Federal de Minas Gerais / Most of Water Treatment Plant (WTP) for public supply in Brazil use surface water as source and conventional complete cycle as treatment system. In this type of treatment wastewater are restrained/generated which vary mainly according to the type and amount of chemical added and the characteristics of the water resource. This wastewater is found mainly in clarifiers (sludge) and backwash water filter (BWF) from WTP. Unfortunately, most of Brazilian WTP launches its waste directly into water resources, violating Brazilian Law 9605 published in 1998. There are mechanical and natural technologies for water removal from wastewater restrained during the treatment. Once known that wastewater from WTP has fluid characteristic, some technologies to remove its water have been developed. A natural one is the drainage bed, developed and proposed by Cordeiro (2001). The drainage bed has basically two stages: drainage and evaporation. This dissertation presents results of a study, whose centre objective was to achieve improvements in water sludge removal restrained in clarifiers by the use of plastic cover (evaporation stage). Results of effective tests in prototypes located in Sao Carlos WTP (Sao Paulo State) with plastic cover have showed that this roof (commercial reference PVC 0.30 milimeters) uses has accelerated the evaporation process, and has protected sludge from rain. The height of the roof that presented the best result was 0.20 meters in relation to the board of prototype, realizing to obtain a sludge 56% dryer than in tests without the roof. Preliminary tests in laboratory scale generated a promising scenario for the use of cationic polymer in large scale doubling the efficiency of the initial drainage of sludge. However, other laboratory tests with different characteristics of geotextile blanket only confirmed the superiority of using woven blanket type with surface density of 600 g/m² (which had already been used in other studies), compared to the others, in reference to obtain better efficiency at the initial drainage of water present in raw sludge. / A maior parte das Estações de Tratamento de Água (ETAs) para abastecimento existente no Brasil se utiliza de captação de águas superficiais e sistema de tratamento de ciclo completo convencional. Neste tratamento são retidos/gerados resíduos que variam principalmente segundo o tipo e quantidade de produto químico adicionado e as características do manancial de captação. Estes resíduos são encontrados principalmente nos decantadores (lodo) e na água de lavagem dos filtros (ALF) das ETAs. Infelizmente, a maioria das ETAs brasileiras lança seus resíduos diretamente em corpos d água, infringindo disposições da Lei 9.605/98. Existem tecnologias mecanizadas e naturais para remoção de água dos resíduos retidos no tratamento. Uma vez que possuem característica fluida, foram desenvolvidas algumas tecnologias para remoção de suas águas. Uma tecnologia natural para remoção de águas de resíduos de ETAs é o leito de drenagem, desenvolvido e proposto por Cordeiro (2001). O leito de drenagem possui basicamente duas etapas envolvidas: drenagem e evaporação. Esta pesquisa apresenta resultados de um estudo, cujo objetivo central foi alcançar melhorias na remoção da água de lodo retido nos decantadores através da utilização de cobertura plástica no leito de drenagem (etapa de evaporação). Resultados obtidos nesta pesquisa para ensaios realizados em protótipos de leitos de drenagem instalados na ETA de São Carlos-SP demonstraram que, quando se utiliza cobertura plástica (referência comercial PVC 0,30 mm), o processo de evaporação da água presente no lodo é acelerado e a ocorrência de precipitação não interfere em momento algum na remoção de água do lodo. A altura da cobertura em relação ao protótipo que apresentou os melhores resultados foi de 0,20 m, permitindo-se obter um lodo final até 56% mais seco que na ausência de cobertura. Ensaios realizados em escala laboratorial para condicionamento prévio do lodo bruto com polímero catiônico apresentaram resultados promissores para sua utilização em maior escala, duplicando a eficiência da drenagem inicial do lodo. Entretanto, outros ensaios laboratoriais com mantas geotêxteis de características distintas apenas confirmaram a superioridade da utilização de manta do tipo tecida de densidade superficial 600g/m² (que já havia sido utilizada em outras pesquisas) em relação às demais, no que se refere à obtenção de melhor eficiência na drenagem inicial da água presente no lodo bruto.
97

Efici?ncia de uma ETE em escala real composta por reator UASB seguido de lodo ativado / Efficiency of a full-scale WWTP consists of UASB reactor followed by activated sludge

Ferraz, Danillo Luiz de Magalh?es 07 March 2014 (has links)
Made available in DSpace on 2014-12-17T15:03:34Z (GMT). No. of bitstreams: 1 DanilloLMF_DISSERT.pdf: 2643693 bytes, checksum: e8aa0f4d4535d4002a68928f7529ab75 (MD5) Previous issue date: 2014-03-07 / In the state of Rio Grande do Norte (RN), Brazil, there are about 80 sewage treatment systems being the predominant technology waste stabilization ponds. The Baldo s WWTP , due to its location and low availability of area, was designed as a hybrid conventional system (UASB reactor followed by activated sludge with biodiscs) at a tertiary level, being the most advanced WWTP in the State and also with the larger treatment capacity (1620 m3/h) .The paper presents the results of its performance based on samples collections from May to December 2012. Composite samples of the effluent of the grit chamber, UASB reactors, anoxic chambers, aeration tanks and treated effluent were collected weekly, every 4 hours for 24 hours. The results showed that the WWTP effluent presented adequate ranges of temperatures, pH and DO, however removal efficiencies of BOD and TSS were below the predicted by design. The UASB reactors also showed removals of BOD and TSS less than expected, due to the accumulation of sludge in the reactors, which eventually, was washed out in the effluent. The nitrification process was not satisfactory mainly due to problems in the oxygen distribution in the aeration tanks. The removal of ammonia and TKN were high, probably by the assimilation process / No Rio Grande do Norte (RN), Brasil existe cerca de 80 sistemas de tratamento de esgotos sendo a tecnologia das lagoas de estabiliza??o a predominantemente utilizada. A ETE do Baldo, devido a sua localiza??o e disponibilidade de ?rea foi concebida como um sistema convencional h?brido (UASB lodos ativados com biodiscos) em n?vel terci?rio, sendo a ETE mais avan?ada do Estado e com maior capacidade de tratamento (1620 m 3 /h). O trabalho apresenta os resultados do seu monitoramento, atrav?s de coletas realizadas semanalmente no per?odo de junho a dezembro de 2012, com base em amostras compostas coletadas a cada 4 horas, durante 24 horas, do efluente da caixa de areia, reatores UASB, c?maras an?xicas, tanques de aera??o e efluente tratado. Os resultados mostraram que a ETE apresentou efluentes com temperaturas, pH e OD adequados, entretanto efici?ncias abaixo do projetado para os par?metros DBO e SST. Os reatores UASB tamb?m apresentaram remo??es de DBO e SST abaixo do esperado, devido ao ac?mulo de lodo nos reatores, uma vez que, este era expelido no efluente. O processo de nitrifica??o n?o foi satisfat?rio, pelas baixas concentra??es de nitrato encontradas nos efluentes dos tanques de aera??o, provavelmente por problemas no sistema de aera??o. As remo??es de am?nia e NTK foram altas, provavelmente pelo processo de assimila??o
98

Incorporação de lodo gerado na Estação de Tratamento de Água Tamanduá, como ativo em massas para cerâmica vermelha / Incorporation of sludge generated in the Tamanduá Water Treatment Plant Incorporated, with addition of a red ceramic mass

Tartari, Rodrigo 05 December 2008 (has links)
Made available in DSpace on 2017-07-10T18:08:09Z (GMT). No. of bitstreams: 1 Rodrigo Tartari.pdf: 9550409 bytes, checksum: 139b195eb1b11dbe7bfc7a238de6d98b (MD5) Previous issue date: 2008-12-05 / The objective of this work is to research the development of methods for utilizing the sludge generated in the Tamanduá water treatment plant, located in the city of Foz do Iguaçu - PR, as a prime material for the production of red ceramic. For this purpose, it was used beyond the mud, four clays originating geological region of western Paraná, called: Plastic (OP) and Sand (AO) from Santa Rita Ceramic and Plastic (AP) and Sand (AA) from de Artisans Cooperative of Foz do Iguaçu PR (COOAFOZ), used for production of red ceramic. The methodology is divided into: characterization of the 5 materials for determination of humidity, organic matter, loss by fire, limits of sil consistency, residues, grain fineness, chemical and mineralogy, in the second phase of the investigation, seven binary mistures were made among the clays from Santa Rira Cermics and from COOAFOZ, varying the weight of both in proportion of 0, 30, 40, 50, 60, 70 and 100%. Were up 336 bodies of evidence by uniaxial pressing, tested dry and after sintering at temperatures of 950 o and 1050 °C, measured before the following tests: total linear contraction, water absorption, apparent porosity, loss by fire, apparent specific mass, strength the bending, scanning electron microscopy and microanalysis. It was found that the clay AP and OP showed characteristics of high plasticity with major composition of SiO2, Al2O3 and Fe2O3 and grains < 2&#956; equivalent to 19.4 and 21.6, respectively. When these clays the AP and OP in greater weight percentages in the mixtures, the intensities of interaction between clay processing were positively evaluate the physical-mechanical properties of bodies of evidence. Mixtures A1 (100% AP), A2 (70% AP + 30% AA), B1 (100% AP) and A2 (70% AP + 30% AA), showed better results on water absorption of less than 25% and resistance to bending than 60 kgf/cm2 at a temperature of 950 °C and more than 80 kgf/cm2 to 1050 oC. In these compositions, is incorporated 4, 8, 12 and 16% of dry sludge to determine the maximum permissible load without causing cracks and deformations. It was found that the sludge presented characteristics of silty clay of low plasticity, can replace clay similar to 8% in the production of red ceramic. According to analysis of results, have been building blocks of 6 holes for the method of extrusion incorporating 8% of wet mud is found that the physical mechanical properties evaluated were: linear contraction of 8.6%, 24% water absorption and 46 kgf /cm2 of resistance to compression, and within the rules for production of red ceramic coating for (bricks). It appears that the sludge was incorporated as the mass of wet clay, about 75% of initial water when received from the water treatment plant Tamanduá, contributing to process of maturation. It was concluded that based on the results obtained in the laboratory that the sludge generated in the water treatment plant of the unit Tamanduá in Foz do Iguaçu - PR can be used as an additive in the manufacture of bodies for red ceramic. / Este trabalho tem por objetivo pesquisar o desenvolvimento de métodos para utilizar o lodo gerado na Estação de Tratamento de Água Tamanduá, localizada na cidade de Foz do Iguaçu/PR, como matéria-prima para produção de cerâmica vermelha. Para atingir a finalidade proposta, utilizaram-se além do lodo, quatro argilas de formação geológica da região oeste do Paraná, denominadas por: Plástica (OP) e Areia (OA) da Cerâmica Santa Rita e Plástica (AP) e Areia (AA) da Cooperativa de Artesões de Foz do Iguaçu PR (COOAFOZ), empregadas para produção de cerâmica vermelha. A metodologia subdividiu-se em: caracterização das 5 matérias-primas pela determinação da umidade, matéria orgânica, perda ao fogo, limites de consistência de solos, resíduos, granulometria, composição química e mineralógica. Na segunda fase da investigação, fez-se sete misturas binárias entre as argilas da Cerâmica Santa Rita e da COOAFOZ, variando o peso de ambas em 0, 30, 40, 50, 60, 70 e 100%. Foram confeccionados 336 corpos de prova por prensagem uniaxial, analisados a seco e após sinterização nas temperaturas de 950 e 1050 oC, avaliados perante os seguintes ensaios: contração linear total, absorção de água, porosidade aparente, perda ao fogo, massa específica aparente, resistência à flexão, microscopia eletrônica de varredura e microanálise. Verificouse que as argilas AP e OP apresentaram características de alta plasticidade com presença majoritária de SiO2, Al2O3, e Fe2O3 e grãos < 2&#956;, iguais a 19,4 e 21,6 respectivamente. As argilas AP e OP em maiores porcentagens peso nas misturas intensificaram as interações entre os argilominerais, isto é, no processamento obtiveram-se resultados positivos diante a avaliação das propriedades físico mecânicas dos corpos de prova. As misturas A1 (100% AP), A2 (70% AP + 30% AA), B1 (100% OP) e B2 (70% OP + 30% OA), apresentaram melhores resultados com relação à absorção de água menor que 25% e resistência à flexão superior a 60 kgf/cm2 na temperatura de sinterização a 950 oC e superior a 80 kgf/cm2 à 1050 oC. Nestas composições, incorporaram-se 4, 8, 12 e 16% de lodo seco para determinar a carga máxima admissível sem causar trincas e deformações. Verificou-se que o lodo apresentou características de argilas siltosas de baixa plasticidade, podendo substituir argilas similares em até 8% na produção de cerâmica vermelha. De acordo com análise dos resultados obtidos, fizeram-se blocos estruturais de 6 furos pelo método de extrusão incorporando 8% de lodo úmido, e verificou-se que as propriedades físico-mecânicas avaliadas foram as seguintes: 8,6% de contração linear, 24% de absorção de água e 46 kgf/cm2 de resistência à compressão, estando dentro das normas de produção de cerâmica vermelha para revestimento (tijolos). Destacou-se que o lodo incorporado na forma úmida à massa de argila, com cerca de 75% de água inicial quando recebido da Estação de Tratamento de Água Tamanduá, contribuiu no processamento de maturação da mesma. Portanto, conclui-se com base nos resultados que o lodo gerado na Estação de Tratamento de Água da unidade Tamanduá em Foz do Iguaçu PR pode ser utilizado como aditivo na fabricação de massas para cerâmica vermelha.
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Kapacitetsminskning hos långsamfiltren vid Lovö och Norsborgs vattenverk : Studie av påverkande faktorer samt åtgärdsförslag / Reduced slow sand filtration capacity at the water treatment plants at Lovö and Norsborg : Reasons and ways on increasing the capacity

Mellander, Mattis January 2015 (has links)
Invånarantalet i Stockholm ökar och därmed också efterfrågan på dricksvatten. Stockholm Vatten VA AB fastslog i sin senaste prognos att kapaciteten hos deras vattenverk i Norsborg och på Lovö kommer att vara otillräcklig inom femton år och därmed måste ökas. Båda vattenverken tar vatten från Mälaren och renar detta genom flockning, sedimentering, snabbfiltrering, långsamfiltrering, UV-bestrålning samt tillsats av kloramin. Baserat på de senaste årens drifterfarenheter har långsamfiltrens kapacitet skrivits ned och är ett begränsande produktionssteg på båda verken. Detta examensarbete syftade till att fastställa orsakerna till kapacitetsminskningen och föreslå åtgärder. Undersökningen begränsades till Lovö vattenverk, men resultaten anses relevanta även för Norsborgs vattenverk.   De senaste åren har långsamsandfiltrens drifttid mellan rensningar minskat och tryckfallet i genomsnitt ökat. Här sågs att tryckfallet direkt efter rensning var högre i den undersökta periodens slut än under periodens början. Då filtrens belastning undersöktes konstaterades att filtreringshastigheten inte ökat och vattenkvaliteten inte försämrats. Utifrån detta drogs slutsatsen att kapacitetsminskningen inte berodde på ökad belastning.    Med hjälp av rör satta i filtersanden kunde tryckfallets fördelning över filterbäddens djup undersökas. I två av de undersökta filtren sågs ett kraftigt tryckfall i filtrens undre del. Då provgropar grävdes i filtren sågs ett tydligt gråaktigt lager vid den nivå där tryckfallet skett. Analyser av sandprover från filtren tydde på att en ackumulering av finkorniga sandpartiklar och organiskt material samt en lågporositet, gav det gråa lagret en låg mättad hydraulisk konduktivitet. Ackumuleringen av finkorniga sandpartiklar skulle kunna bero på att finkornigt material lyfts från filtrens hörn, där sandlagret är tunnare, och fördelas över resterande delar av filtret vid återfyllnad efter rensning.   Mätningar av porositet visade att filterbädden kompakteras då det belastas av de fordon som används vid rensning. Resultaten tyder dock på att packningens utbredning och omfattning är sådan att den inte har någon större effekt på tryckfallet i filtret. / Stockholm is growing and with it the demand for drinking water. To meet the demand the capacity of the two water treatment plants in Norsborg and at Lovö must be increased. Both plants use water from the lake Mälaren which is treated using flocculation, sedimentation, rapid filtration, slow sand filtration, UV-light and the addition of chloramine. The estimated capacity of the slow sand filters has decreased at both plants during the last few years and is limiting the total production capacity. This study aims to find the cause of the capacity decrease and make suggestions for how the capacity could be increased. Only the water treatment plant at Lovö was examined in this study, but the results are considered to be relevant for the water treatment plant in Norsborg as well.   During recent years the runtime of the filters has been decreasing and the overall loss of hydraulic head has increased. In several filters it was noted that the hydraulic head loss after filter cleaning had increased over time. Filter load was examined during the period in which the loss in capacity took place. Neither had the filtration rate increased nor had the water quality decreased. A higher load could therefore be ruled out as the source of the capacity loss.   Hydraulic head loss distribution over the depth of the filter beds was examined using steel pipes placed in the filter bed at different depths. In two filters a large hydraulic head loss was found at a narrow section in the bottom of the filters. Holes were dug in the filter beds, from which a distinct grey layer could be observed. Sand analyses showed that an accumulation of fine sand particles and organic matter combined with a low porosity could have been what caused the large hydraulic head loss in the layer. This material could have originated from the corners of the filters. During filter refill, fine material was observed being suspended from the corners and spread across the filter.   Measurements of sand porosity suggested that the filter bed is compacted by the machines used to clean the filters. This however seemed to have a negligible effect on the hydraulic head loss in the filters.
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Nakládání s odpadními vodami v obci Sudice / Wastewater management in the village Sudice

Hoferková, Lenka January 2018 (has links)
This thesis is written due to the poor quality of the stream Sudický potok and the fish kills in nearby ponds supplied by the stream. The goal is evaluating the results of the water samples obtained from the four local spots. Polluted quality in the stream in the Sudice town then proceed to design three various solutions of the sewage collection systems. The first option is designing the municipal wastewater treatment plant and the draining wastewater by single sewerage or sanitary sewerage. The second choice designs the domestic waste water treatment plants. The third solution is designing the sanitary sewerage and effluent sewerage to the nearby waste water treatment plant in Šebetov town. All variants are economically evaluated. In conclusion the first solution, municipal waste water treatment plant with the single sewerage, is recommended.

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