L'industrie minière produit d'énormes quantités de déchet (millions de tonnes par an), souvent sous forme de boue à cause de la forte teneur en eau et en argile. Ces boues liquides sont problématiques car elles se consolident très lentement : elles limitent la réhabilitation des parcs à résidus où elles sont stockées et augmentent le risque de rupture des barrages entourant les parcs à résidus (coulée de boue). Améliorer l'assèchement des boues minières est nécessaire afin d'augmenter la stabilité des parcs à résidus et de recycler l'eau contenue dans la boue. La solution proposée dans cette thèse consiste à insérer des géocomposites de drainage (GCP) dans les parcs à résidus afin de permettre à l'eau contenue dans la boue de s'évacuer. Pour mobiliser l'eau dans ces boues à faible conductivité hydraulique, deux phénomènes ont été investigués : la consolidation des boues sous contrainte mécanique et la migration de l'eau par électro-osmose (EO). Afin d'attester de la faisabilité d'appliquer ces 2 phénomènes avec des GCP, chacune des fonctions des GCP a été évaluée : les fonctions de base (filtration et drainage) pour provoquer l'asséchement mécanique et une nouvelle fonction de conduction électrique pour appliquer l'EO.La filtration de boue par géotextile (GTX) a été investiguée car contrairement à la filtration de sol, elle demeurait peu décrite dans la littérature et semblait délicate à cause de l'argilosité de la boue. Des tests de filtration sous pression ont permis de tester 8 GTX avec une même boue argileuse, puis 8 boues de granularités différentes avec un même GTX. Les résultats indiquent que les GTX n'ont un impact qu'au début de la filtration : ils retiennent les particules les plus grossières ce qui induit la formation d'un gâteau de filtration qui devient rapidement l'élément filtrant, le GTX n'est alors plus qu'un support. Une même boue filtrée par 8 GTX différents conduit à un même assèchement alors que les 8 boues différentes filtrées avec un même GTX conduisent à 8 assèchements différents : l'assèchement final est contrôlé par la composition de la boue et est totalement indépendant du GTX utilisé. Ces essais de filtration ont permis d'évaluer l'assèchement mécanique des boues : la pression appliquée (50kPa) conduit à l'expulsion de l'eau libre, alors que l'eau liée reste dans la boue. Cela est dû aux différents niveaux de liaison de l'eau dans la boue : l'eau liée ne peut être extraite mécaniquement. Ainsi les fonctions de base des GCP provoquent un asséchement mécanique du à l'augmentation de la contrainte lors du remplissage des parcs à résidus. En revanche, l'asséchement mécanique est limité à l'extraction de l'eau libre ; il est apparu essentiel de proposer un nouveau moteur pour extraire l'eau liée.La principale innovation de ce travail est l'ajout d'une nouvelle fonction au GCP : l'ajout d'éléments conducteurs dans les GCP permet d'appliquer l'EO dans les boues. Ce phénomène permet de mobiliser une partie de l'eau liée en imposant un courant électrique. Des prototypes de GCP électrocinétique (eGCP) ont été développés et testés dans un dispositif expérimental dédié. Les résultats montrent que la filtration et la conduction électrique sont assurées efficacement par les eGCP disposés de part et d'autre de la boue. La boue testée est issue des sables bitumineux (FFT) et est très problématique car sa consolidation est extrêmement lente. Les résultats obtenus sont très encourageants : la phase mécanique porte la siccité de la boue de 45% à 61%, puis l'EO permet d'atteindre une siccité de 77% et une résistance au cisaillement de 77 kPa, alors que la réglementation exige d'atteindre 10 kPa.Pour conclure, les différentes expérimentations montrent que les boues minières peuvent être asséchées par des GCP en cumulant les effets de la compression mécanique, grâce aux fonctions classiques des GCP et de l'EO grâce à l'ajout d'une nouvelle fonction de conduction électrique. Cette solution a fait l'objet d'un brevet / A host of mining practices produces huge quantity of fine-grained mineral sludges whose disposal in ponds is often challenging. The key problem caused by these sludges is their very poor geotechnical properties, which are caused by their high water and clay content. These sludges are hard to dewater because of their low hydraulic conductivity. Dewatering sludges to increase its shear strength and reduce the volume of material to be contained thus represents a preferred path to reduce the risk of pond's failure, reduce the pond's footprint, and maximize water recycling. To dewater mining sludges, the solution foreseen in this PhD is to intercalate some geocomposites (GCPs) layers within the sludge-disposal area to create draining horizons to permit mechanical dewatering and to apply electro-osmosis (EO) across sludges layers to induce water migration. To evaluate the efficiency of GCPs at enhancing sludges dewatering by both of these phenomena, the different functions of GCPs (filtration, drainage, and electric conduction) were experimentally investigated during this PhD.To study sludge filtration by geotextile (GTX), pressure filtration tests were used to filter 8 different high-clay-content sludges with 8 different nonwoven GTXs. Only a few studies have considered the filtration of sludge by GTXs. The sludges were formulated by mixing kaolinite and silt to obtain 8 different grain-size distributions. The results indicate that sludges can be filtered with nonwoven GTXs selected on the basis of their pore-opening size. In addition, only during the early stage of filtration GTXs really influence filtering because it is at this stage that, by retaining coarser particles, they allow progressive formation of filter cake. Upon forming, the filter cake becomes the major contributor to particle retention. The sludge composition is found to be the most significant factor affecting the final state of dewatering. In other words, the GTX does not control the final dewatering; the sludge itself controls the final solid content. These filtration tests showed that mechanical dewatering is effective for removing free water, but bounded water remains in the sludge because of the high bonding forces between water and solid matter. Facing this limitation of mechanical dewatering, a new way to extract bounded water had to be proposed.The main innovation brought by this PhD concerns the addition of a new function to GCP, by adding conductive elements into the GCP to apply EO in the sludge. Electro-osmosis (EO) forces water to migrate from anode to cathode and is sufficient to remove a significant portion of bounded water that cannot be removed by mechanical dewatering. Some prototypes of electro-kinetics GCP (eGCP) were developed, and tested in a new laboratory setup. This experimental device was developed to evaluate simultaneously the different functions of eGCPs, namely, drainage or filtration and electrical conductivity. It has the particularity that it uses eGCPs as both a draining medium and electrode. The results show that fluid fine tailings (FFTs), a particularly hard to dewater sludge from oil-sand exploitation, are significantly dewatered by the combination of normal stress compression, and then EO treatment: the FFT solids content increased from 45% to 61% during the compression phase and to 77% during the EO phase. The applied treatment led to a significant consolidation of the FFT: shear strength increased from zero to about 77 kPa which is significantly greater than the 10 kPa required by government regulations.To conclude, eGCPs can drain water expulsed during sludge consolidation in response to the filling of the disposal area, thanks to the classical function of GCP, as well as impose a voltage across FFT to displace water by electro-osmosis from anode to cathode, thanks to conductive elements embedded in eGCP. This solution was patented at the end of the PhD.

Abstracts Cellulose nanopapers are the strongest polymeric material known to us, and in the near future, they are likely to be a backbone of numerous functional materials. Cellulose nanopapers have gained much attention due to qualities such as their environmentally friendly nature, renewable raw material source and biodegradability. Additionally, they offer an industrially adaptable, water-based processing route, which is similar to current paper production. Functionally, besides being tougher than any known plastic, cellulose nanopapers remain foldable like a paper. Despite their fascinating properties, cellulose nanopapers are still far from commercialisation – mainly due to two obstacles. Firstly, it can take up to hours to prepare a nanopaper due to poor draining of cellulosic nanofibres. Secondly, cellulose nanopapers have extremely poor water and humidity resistance, as up to 90% of their stiffness is lost in the presence of water. The purpose of this dissertation is to address both obstacles and suggest an eco-friendly yet industrially relevant solution. Two approaches are employed: increasing the hydrophobicity of cellulose nanofibres with lactic acid and ultrasonication (Paper I and II), and combining cellulose nanofibres with hydrophobic materials, such as polyurethane (Paper III) and lignin-rich entities (Paper IV). By using these methods, the preparation time was improved by 75% (Paper II) and by 70% (Paper IV) respectively. All reported nanopapers were significantly more tolerant of water and moisture than the reference nanopaper. The mechanical properties were also improved in Paper I and IV. Additionally, all reported nanopapers were thermally stable. This thesis also discusses the importance of quick draining in cellulose nanofibre-reinforced paper products. The results of this study are likely to aid the commercialisation of cellulose nanopapers in practical applications and the use of cellulose nanofibres in other materials, such as reinforcing paperboards. All methods used in this thesis are water-based. / Tiivistelmä Selluloosapohjaiset nanopaperit ovat lujimpia tunnettuja polymeerimateriaaleja ja lähitulevaisuudessa niiden voidaan odottaa luovan perustan useille funktionaalisille materiaaleille. Nanopaperit ovat saaneet paljon huomiota ympäristöystävällisyytensä, uusiutuvan raaka-aineensa ja biohajoavuutensa ansiosta. Lisäksi niiden valmistusprosessi on vesipohjainen ja samankaltainen kuin tavallisen paperin valmistukseen käytetty teollinen prosessi. Käyttöominaisuuksiltaan ne ovat erinomaisia, sillä vaikka niiden sitkeys on parempi kuin tunnetuilla muoveilla, ovat ne silti paperin tavoin taiteltavia. Kiehtovista ominaisuuksistaan huolimatta selluloosapohjaiset nanopaperit ovat kuitenkin vielä kaukana kaupallistamisesta ja tähän vaikuttavat pääosin kaksi tekijää. Tärkein syy on selluloosananokuitujen kuivattamisen ja näin ollen nanopaperin muodostamisen vaatima huomattavan pitkä aika. Nykyisillä menetelmillä nanopaperin valmistaminen kestää useita tunteja. Toinen syy on niiden erittäin huono veden- ja kosteudenkestävyys. Ne menettävät jopa 90 % jäykkyydestään veden vaikutuksesta, mikä rajoittaa niiden käyttöä kosteissa ja vesiroiskeille alttiissa kohteissa. Tämän väitöskirjatutkimuksen päätavoitteena on löytää ekologisesti kestävä ja teollisuudessa hyödynnettävissä oleva menetelmä molempien edellä mainittujen ongelmien ratkaisemiseksi. Työssä noudatetaan kahta eri lähestymistapaa: lisätään selluloosananokuitujen hydrofobisuutta maitohapon ja ultrasonikoinnin avulla (Artikkelit I ja II), ja yhdistetään selluloosananokuituihin hydrofobisia materiaaleja, kuten polyuretaania (PU) (Artikkeli III) ja ligniinipitoisia yhdisteitä (Artikkeli IV). Näitä menetelmiä käyttämällä valmistusaikaa saatiin lyhennettyä 75 % (Artikkeli II) ja 70 % (Artikkeli IV). Kaikki valmistetut nanopaperit olivat huomattavasti veden- ja kosteudenkestävämpiä kuin verrokkinäytteet sekä osoittivat lämpöstabiiliutta. Lisäksi mekaanisia ominaisuuksia saatiin parannettua Artikkeleissa I ja IV. Tässä työssä käsitellään myös nopean kuivattamisen tärkeyttä selluloosananokuitulujitteisten paperituotteiden valmistuksessa. Saadut tulokset todennäköisesti edistävät selluloosapohjaisten nanopaperien kaupallistamista ja selluloosananokuitujen hyödyntämistä esimerkiksi kartongin lujitemateriaalina. Kaikki työssä käytetyt menetelmät ovat vesipohjaisia.

Made available in DSpace on 2016-06-02T20:00:45Z (GMT). No. of bitstreams: 1 4632.pdf: 8984815 bytes, checksum: 8d68f51689a782923b2bcfbb5000f4a3 (MD5) Previous issue date: 2012-05-21 / Financiadora de Estudos e Projetos / Substances in Sewage Sanitary exert deleterious effects on bodies of water; the organic matter which is present may cause a decrease in concentration of dissolved oxygen, killing fish and other aquatic organisms, eutrophication by the presence of nutrients causing an accelerated growth of algae that give odor, taste and biotoxins to the water,darkening and siltation of the watercourse. In this scenario, it is of great importance the need for sewage treatment. However, in the treatment process, occurs the production of sludge rich in organic matter and nutrients, known as sewage sludge. This residue at the end of the treatment process should receive special attention, requiring proper disposal. Moreover, it is found that several sewage treatment projects do not include the final destination of the sludge that is produced, which results in the partial annulment of the benefits of collecting and treating collected wastewater. Therefore, this study presents results of analyzes performed on sludge from sewage treatment contained in BAG's of Geotextile Blanket of ETE-Limoeiro / SABESP, located in the city of Presidente Prudente, SP. The objective of this work was to characterize the physico-chemical and microbiological parameters in accordance with Resolution N° 375/06 of Conselho Nacional do Meio Ambiente CONAMA, and evaluate the efficiency of dewatering of sludge. Based on this, the analysis of identification and quantification of heavy metals showed values below the maximum allowed concentrations in sludge. Regarding the assessment of macro and micronutrients, analysis showed that the sludge has significant amounts of essential nutrients to the soil and plants and it can be used for this purpose after specific treatment. Regarding the biological tests for quantification of fecal coliforms, the obtained concentrations showed values that were established for the sludge Class B. The sludge was also evaluated for stability using the relation between volatile solids and total solids. This relation presented results for SV/ST below 0.70 which allowed defining the sludge as stable according to Resolution 375/06. However, the evaluation of the water removal process showed commitment of the dewatering efficiency according to the characteristics of the sludge generated in the Sewage Treatment Plant. Geotêxtil da ETE-Limoeiro / SABESP, localizada no Município de Presidente Prudente-SP. O objetivo central desta pesquisa foi à caracterização dos parâmetros físico-químicos e microbiológicos em conformidade com a Resolução Nº 375/06 do Conselho Nacional do Meio Ambiente CONAMA, e a avaliação da eficiência do processo de remoção de água dos lodos. Ante o exposto, as análises para identificação e quantificação de metais pesados apresentaram valores abaixo das concentrações máximas permitidas em lodos. Em relação à avaliação de macro e micronutrientes, as análises demonstraram que o lodo possui quantidades significativas de nutrientes essenciais aos solos e plantas, podendo ser utilizado para esta finalidade após tratamento específico. Referente às análises biológicas para quantificação de coliformes termotolerantes, as concentrações obtidas apresentaram valores estabelecidos para lodos Classe B. Os lodos também foram avaliados quanto à estabilidade através da relação entre sólidos voláteis e sólidos totais. Esta relação apresentou resultados para SV/ST inferiores a 0,70 permitindo definir os lodos como estáveis de acordo com a Resolução 375/06. Entretanto, avaliação do processo de remoção de água, demonstrou comprometimento da eficiência do desaguamento em função das características do lodo gerado na Estação de Tratamento de Esgotos. / As substâncias presentes nos esgotos sanitários exercem ação deletéria nos corpos de água, a matéria orgânica presente pode causar a diminuição da concentração de oxigênio dissolvido provocando a morte de peixes e outros organismos aquáticos, eutrofização pela presença de nutrientes provocando o crescimento acelerado de algas que conferem odor, gosto e biotoxinas á água, escurecimento e assoreamento do curso d água. Diante deste cenário, é de suma importância a necessidade do tratamento dos esgotos. Porem no processo de tratamento ocorre à produção de um lodo rico em matéria orgânica e nutriente, denominado lodo de esgoto. Este resíduo ao final do processo de tratamento deve receber uma atenção especial, necessitando de adequada disposição final. Contudo, constata-se que geralmente vários projetos de tratamento de esgotos não contemplam o destino final do lodo produzido, acarretando assim na anulação parcial dos benefícios da coleta e do tratamento dos efluentes coletados. Neste sentido, esta pesquisa apresenta resultados de análises realizadas em lodos de estação de tratamento de esgoto contidos em BAG´s de Manta Geotêxtil da ETE-Limoeiro / SABESP, localizada no Município de Presidente Prudente-SP. O objetivo central desta pesquisa foi à caracterização dos parâmetros físico-químicos e microbiológicos em conformidade com a Resolução Nº 375/06 do Conselho Nacional do Meio Ambiente CONAMA, e a avaliação da eficiência do processo de remoção de água dos lodos. Ante o exposto, as análises para identificação e quantificação de metais pesados apresentaram valores abaixo das concentrações máximas permitidas em lodos. Em relação à avaliação de macro e micronutrientes, as análises demonstraram que o lodo possui quantidades significativas de nutrientes essenciais aos solos e plantas, podendo ser utilizado para esta finalidade após tratamento específico. Referente às análises biológicas para quantificação de coliformes termotolerantes, as concentrações obtidas apresentaram valores estabelecidos para lodos Classe B. Os lodos também foram avaliados quanto à estabilidade através da relação entre sólidos voláteis e sólidos totais. Esta relação apresentou resultados para SV/ST inferiores a 0,70 permitindo definir os lodos como estáveis de acordo com a Resolução 375/06. Entretanto, avaliação do processo de remoção de água, demonstrou comprometimento da eficiência do desaguamento em função das características do lodo gerado na Estação de Tratamento de Esgotos.

I en värld med ökande koldioxidhalter i atmosfären och höjd medeltemperatur, råder det inga tvivel om att vi står inför en rad utmaningar för att minska användandet av bland annat fossila bränslen som generar skadliga utsläpp. Det finns många alternativ till oljebaserade bränslen, och ett som har ökat markant de senaste åren är bränslepellets. Bränslepellets är ett träbaserat biobränsle som i sitt kompakta tillstånd erbjuder ett bra värmevärde och är klimatneutralt. För att tillverka pellets måste råmaterialet först termiskt torkas, från en fukthalt på ca 55 % till ca 10 %, vilket i dagsläget kan motsvara upp till en fjärdedel av hela energiåtgången i pelleteringsprocessen. Med den ökade efterfrågan av bränslepellets finns också ökade förutsättningar för energieffektiviseringar i pelletsproduceringen, speciellt i torkningssteget.   Drinor AB har tagit fram en avvattningsmaskin av biomaterial som heter CDP, och med den är det möjligt att avvattna biomaterial till ca 30 %, vilket skulle reducera både tiden och energin det tar att termiskt torka materialet. Avvattningen sker under tryck på minst 40 ton, där vattnet mekaniskt pressas ut ur råmaterialet. Hur avvattningen påverkar råmaterialet, speciellt i en pelletframställning, är oklart och syftet med detta arbete var att ta reda på hur pelleteringsegenskaperna påverkas efter pressning med CDP, och om det finns möjligheter att spara energi i malningsdelen i pelleteringsprocessen.   Målet med arbetet var att ta reda på hur CDP påverkar pelletskvaliteter i form av hårdhet och densitet, samt om friktionsutvecklingen i pelleteringsmatrisen förändras, genom att framställa pellets ur 3 scenarion. I ett scenario ska en traditionell pelletsframställning liknas, med endast termisk torkning och i de resterande två scenarion implementeras CDP som försteg till den termiska torkningen. I ett av dessa två scenarion mals inte träflisen innan pelletering, för att se om energi kan sparas utan att offra pelletskvalitet. Ett annat mål var att, per scenario, ta reda på vid vilken fukthalts- och temperaturkombination de bästa pelletsen tillverkades med avseende på hög densitet och hårdhet samt låg friktionsutveckling.   Resultaten visade att scenariot med CDP som komplement till termisk torkning och utan malningprocess, producerade pellets med högst hårdhet, högst densitet och lägst friktionsutveckling under båda fukthalterna på pelleteringsmaterialet och nästintill samtliga matristemperaturer. Det scenario som hade endast termisk torkning producerade pellets med lägst densitet och hårdhet samt högst friktion under nästan alla temperaturer och fukthalter.   När den bästa fukthalts- och temperaturkombinationen togs fram per scenario, så var scenariot med CDP och utan malning bäst. Pellets producerade där hade ökad densitet, nästan tredubblad hårdhet samt mer än halverad friktionsutveckling i pelleteringsmatrisen, jämfört med scenariot som imiterade traditionell pelletsframställning med endast termisk torkning.   Skulle det scenariot med CDP och utan malningsprocess implementeras i en verklig industriell skala skulle det innebära stora förutsättningar för ökad produktion av pellets med bättre kvalitet, samt ett minskat energianvändande i form av reducerad termisk torkning och minskat användande av malningsprocessen. / In a world with growing carbon dioxide contents in the atmosphere and elevated average temperature, there is no doubt that we are faced with a number of challenges to reduce the use of, among other things, fossil fuels that generate harmful emissions. There are many alternatives to oil-based fuels, and one that has increased markedly in recent years is fuel pellets. Fuel pellets are a wood-based biofuel that, in its compact state, offers a good thermal value and is climate neutral. In order to produce pellets, the raw material must first be thermally dried, from a moisture content of about 55 % to about 10 %, which can currently account for up to at least a quarter of the total energy consumption in the pelleting process. With the increased demand for fuel pellets, there are also increased possibilities for energy efficiency in the pellet production, especially in the drying stage.   Drinor AB has developed a biomaterial dewatering machine called CDP, with which it is possible to drain the biomaterial to a moisture content of about 30%, which would reduce both the time and the energy it takes to thermally dry the material. The dewatering pressure is at least 40 tonnes, where the water is mechanically squeezed out of the raw material. How the dewatering affects the raw material, especially in a pellet production, is unclear and the purpose of this work was to find out how the pelleting properties are affected after pressing with CDP and if there is potential for saving energy in the grinding process in the pelleting process.   The aim of the work was to find out how CDP affects pellet qualities in terms of hardness and density, and if the friction development in the pelleting dye changes, by making pellets out of 3 scenarios. In one scenario, traditional pellets production should be resembled, with only thermal drying, and in the remaining two scenarios, CDP is implemented as a complement to thermal drying. In one of these two scenarios, the wood chips were not milled before pelleting, to see if energy can be saved without sacrificing pellet quality. Another goal was to determine, by each scenario, what moisture and temperature combination the best pellets were produced with respect to high density and hardness and low friction development.   The results showed that the CDP scenario, as a complement to thermal drying and without grinding process, produced the hardest pellets, highest density and lowest friction development during both moisture levels of the pelleting material and almost all die temperatures. The scenario that only had thermal drying produced pellets with the lowest density and hardness, as well as maximum friction under almost all temperatures and moisture levels.   When the best moisture and temperature combination was achieved by each scenario, the scenario with CDP and without grinding was the best. Pellets produced there had increased density, almost triple the hardness, and more than half the friction development in the pelleting die, compared to the scenario that imitated traditional pellets production with only thermal drying.   Should the scenario with CDP and without grinding process be implemented on a real industrial scale, it would provide great conditions for increased production of better quality pellets, as well as reduced energy use in the form of reduced thermal drying and reduced use of the grinding process.

O método de desaguamento por leitos de drenagem foi desenvolvido por Cordeiro a partir do ano de 1993 (CORDEIRO, 2001) para o desaguamento de lodos de Estações de Tratamento de Água. A sua aplicação para lodos de lagoas de estabilização de esgotos foi feita por Fontana et al. (2007). Este trabalho teve por objetivo avaliar a utilização de leitos de drenagem no desaguamento de lodos produzidos em reatores UASB. Para tanto foram realizados ensaios em laboratório, utilizando testes do tempo de drenagem, para avaliar a influência de diferentes doses e tipos de polímeros no desaguamento do lodo. Alguns geotêxteis foram utilizados como meio filtrante nos funis de Buchner e também avaliados pelo teste do tempo de drenagem. Após escolhidas a manta e o polímero que apresentaram os melhores resultados em laboratório, foram desenvolvidos ensaios em escala piloto, com a utilização de três unidades cobertas de leitos de drenagem, cada um com dimensões de 1,58 m x 1,09 m por 0,5 m de altura. Para a avaliação do efeito das diferentes doses de polímero em escala piloto, foram utilizadas doses de polímero de 0 a 8 g/kg de sólidos totais (peso seco) e mantida a taxa de aplicação de sólidos em 15 kgST/m².ciclo (a concentração de sólidos no lodo foi de aproximadamente 27 g/L). Os resultados indicaram que com doses de polímero =2 g/kgST (peso seco) obtinha-se teor de sólidos no lodo de cerca de 13% após 1 dia e 20% após 10 a 15 dias. Para se atingir teor de sólidos de 25 a 30% o período de secagem necessário foi de cerca de 30 dias. Embora que mesmo sem a aplicação de polímeros o comportamento do lodo fosse semelhante ao de lodos condicionados com polímero, em relação à evolução do teor de sólidos em função dos períodos de secagem, observou-se certa dificuldade na remoção do lodo desaguado e principalmente na limpeza das mantas geotêxteis. Para avaliar diferentes taxas de aplicação superficial de sólidos, foram ensaiadas taxas entre 9 e 22 kgST/m².ciclo. A evolução do teor de sólidos, ao longo do período de secagem dos 3 ensaios realizados, indicou que taxas mais altas de aplicação de sólidos não diminuem as velocidades de secagem, sugerindo que, inclusive, taxas mais altas poderiam ser ensaiadas. / The method of dewatering sludge through Drainage Beds was originally developed in 1993 by Cordeiro (CORDEIRO, 2001) with sludge from Water Treatment Plants. Fontana et al. (2007) used sludge from wastewater stabilization ponds with positive results. The purpose of this research is the evaluation of the drainage bed method to dewater sludge from UASB reactors. Several laboratory trials were performed, measuring drainage times to assess the influence of different polymer types and doses on sludge dewatering. Few geotextiles were used as filter on the drainage time test to evaluate their performance. Once the polymer and the geotextile that best performed in the laboratory were chosen, several pilot experiments were performed with the use of three covered units of drainage beds, each measuring 1.58m x 1.09m (width) x 0.5m (height). For the evaluation of different polymer conditioning doses on a pilot scale, doses from 0 to 8 g/kg of total solids (dry weight) were used and the applied rate of solids kept at 15 kgTS/m².cycle (the concentration of solids in the sludge was of approximately 27 g/L). Results indicated that with the use of polymer doses =2 g/kgTS (dry weight), approximately 13% of total solids in the sludge was observed after one day, which increased to approximately 20% after 15 days. To reach 25% to 30% of total solids in the sludge, the drying time required was circa 30 days. Even without the application of polymers, the behavior of sludge in terms of total solids during the drying period was similar to the sludge conditioned with polymers. Although, with the unconditioned sludge, some difficulty to remove the dewatered sludge cake was observed, mainly in cleaning of the geotextile sleeves. In order to evaluate different application rates of solids, the pilot experiments included rates between 9 and 22 kgTS/m².cycle. The behavior of the total solids in the cake during the drying period of the three experiments suggested that the higher rates of application of solids does not reduce the drying speed, indicating that higher rates can be targeted in future research projects.

Made available in DSpace on 2014-07-29T15:01:43Z (GMT). No. of bitstreams: 1 dissertacao daniela de s s bufaical 2010.pdf: 546520 bytes, checksum: 6c1b30b52d2b46ab060381d4e8c948d9 (MD5) Previous issue date: 2010-08-31 / This study aimed to evaluate the efficiency of a constructed wetlands planted with the vegetal species white ginger (Hedychium coronarium J. König), narrow leaf cattail (Typha angustifolia L.) and papyrus sedge (Cyperus gigantus) under three charges application of the sludge from the sewage treatment station of Goiânia, Goiás, Brazil, in the reduction of thermotolerant coliforms and viable helminths eggs and sludge dewatering. It also aimed to characterize the sludge and to evaluate the quality of the filtrate, and to investigate the occurrence of substances excreted by the macrophytes roots, which may help reduce pathogens. The experiment was conducted at the Goiânia sewage treatment station. To evaluate the reduction of pathogens, the sludge dewatering and the filtrate quality were used 12 plastic containers, each one with 1 m3 of volumetric capacity, filled with support media containing 5 cm of gravel number one, a geotextile blanket and 20 cm of sand. In the gravel was installed a drainage system of gases, consisting of a PVC tube with 25 mm in diameter, in an "L" format, whose horizontal portion was drilled with holes of 4 mm in diameter. The sludge was applied at application rates of 43, 140 and 248 kg TS m-2 year, bringing the rates of 20, 70 and 120 L m-2 week, respectively. The applications of sludge were divided into two times a week, half on Tuesdays and half on Fridays. After three months of application, samples were taken from the dewatered sludge every 14 days, and sent to the laboratory for solids, thermotolerant coliforms and viable helminths eggs determination. During three weeks the filtrate was collected in each container and submitted to analysis of solids and thermotolerant coliforms. To investigate the release of toxins by macrophytes roots were used four 20 L buckets containing sand as support medium. Three buckets were planted with the species of macrophytes and one wasn t planted. The buckets were irrigated with dechlorinated water for four months, keeping the water level inside the buckets at 5 cm from the substrate surface. After this period 2 L samples of effluent from each bucket were collected and sent to the laboratory to investigate the antimicrobial activity. The results were analyzed using the Statistical Analysis System (SAS), performing F and Tukey Kramer (5% probability) tests. About the filtrate there was no significant difference in the removal of solids and thermotolerant coliforms in the rates of 70 L m-2 week and 120 L m-2 week. At the rate of 20 L m-2 week there was no filtrated material. For the dewatered sludge there was no significant difference in the removal of thermotolerant coliforms, viable helminths eggs and solids concentration among the treatments. The total solids were lower at the application rate of 120 L m-2 week. Plant development was hampered by sludge application and at the application rate of 120 L m-2 week, the species narrow leaf cattail and papyrus sedge had died after three months of sludge aplication. The extracts found at the water in contact with the macrophytes roots didn t inhibit microbial activity. The dewatered sludge treated by the constructed wetlands attended the 375 Conama Resolution for type A sludge for viable helminthes eggs and for type B sludge for thermotolerant coliforms / Os objetivos deste estudo foram avaliar a eficiência do sistema de tratamento do tipo leito de macrófitas plantados com as espécies vegetais lírio do brejo (Hedychium coronarium J. König), taboa (Typha angustifolia L.) e papirus (Cyperus gigantus), em três taxas de aplicação de lodo da Estação de Tratamento de Esgoto de Goiânia, na redução de coliformes termotolerantes e de ovos viáveis de helmintos e no desaguamento do lodo. Realizar a caracterização do lodo e avaliar a qualidade do filtrado, bem como investigar a ocorrência de liberação de substâncias excretadas pelas raízes das macrófitas, que possam auxiliar na redução dos patógenos. O experimento foi conduzido na ETE Goiânia (GO). Para avaliação da redução dos patógenos, desaguamento do lodo e avaliação do filtrado foram utilizados 12 contenedores plásticos de 1 m3 cada, preenchidos com meio suporte contendo 5 cm de brita no 1, manta geotextil e 20 cm de areia. Na brita foi instalado um sistema de drenagem de gases, constituído por um tubo de PVC de 25 mm de diâmetro, em formato de ele , cuja parte horizontal foi perfurada com furos de 4 mm de diâmetro. Na areia foram plantadas mudas das espécies vegetais, oito mudas por contenedor. Três contenedores não foram plantados, servindo de tratamento testemunha. Nos contenedores o lodo foi aplicado em taxas de 43, 140 e 248 kg ST m-2 ano, perfazendo as taxas de 20, 70 e 120 L m-2 semana, respectivamente. As aplicações do lodo foram realizadas duas vezes por semana, metade na terça-feira e metade sexta-feira. Após três meses de aplicação, foram realizadas coletas do lodo desaguado a cada 14 dias, e enviadas ao laboratório para realização das análises de sólidos totais, coliformes termotolerantes e ovos viáveis de helmintos. Durante três semanas foi coletado o filtrado de cada contenedor para realização das análises de sólidos totais e coliformes termotolerantes. Para investigação da liberação de toxinas pelas macrófitas foram utilizados quatro baldes de 20 L contendo meio suporte de areia lavada. Os baldes foram plantados com cada espécie de macrófita e um não foi plantado. As macrófitas plantadas nos baldes foram irrigadas com água sem cloro durante quatro meses, mantendo-se o nível de água a 5 cm da superfície do substrato. Após esse período foram coletados 2 L de amostra de efluente de cada balde e enviadas para o laboratório de pesquisa de produtos naturais para a realização de ensaios de investigação de atividade antimicrobiana. Os resultados foram analisados pelo Statistical Analysis System (SAS), realizando-se os testes F e de Tukey Kramer, a 5% de probabilidade. No filtrado não houve diferença significativa na remoção de sólidos totais e coliformes termotolerantes nas taxas 70 L m-2 semana e 120 L m-2 semana e a taxa 20 L m-2 semana não apresentou filtrado. No lodo não houve diferença significativa na remoção de coliformes termotolerantes, ovos viáveis de helmintos e concentração de sólidos entre os tratamentos. A concentração de sólidos totais foi menor na taxa de aplicação de 120 L m-2 semana. O desenvolvimento das plantas foi prejudicado pela aplicação do lodo e na taxa 120 L m-2 semana, após 3 meses de aplicação, as espécies vegetais taboa e papirus morreram. Os extratos encontrados na água em contato com as raízes das macrófitas não inibiram a atividade microbiana. O lodo submetido ao tratamento do tipo leito de macrófitas atende à Resolução Conama 375 para o lodo tipo A para ovos viáveis de helmintos e lodo tipo B para coliformes termotolerantes.

Dans un contexte d’augmentation des volumes de boues résiduaires produits, comprendre et optimiser les processus de déshydratation mécanique est crucial. Leurs performances conditionnent tant le fonctionnement global de la station que son bilan environnemental et économique. En effet, la siccité des boues déshydratées impacte fortement les procédés ou filières permettant leur valorisation à l’échelle des territoires (compostage, valorisation agronomique directe, incinération, …) ainsi que leur bilan environnemental direct et indirect (tonnages à transporter, ...). De plus, les filtrats devront être traités par la station, et leur composition influence significativement le fonctionnement de la filière de traitement des eaux. Les filtres-presses font partie des procédés de déshydratation mécanique les plus utilisés dans les filières boues des stations d’épuration des eaux usées. Leurs performances sont fonction à la fois de leurs paramètres de fonctionnement et des propriétés de la boue à déshydrater. Les connaissances actuelles sont cependant insuffisantes pour permettre (1) d’expliquer pourquoi certaines boues se déshydratent mieux que d’autres et (2) de relier ces phénomènes aux processus mis en oeuvre lors de la déshydratation mécanique. Le poste de déshydratation fonctionne ainsi comme une boîte noire à partir de laquelle il est difficile de prédire les performances d’un outil de déshydratation appliqué à une boue particulière et d’anticiper des dysfonctionnements. Dans ce contexte, l’objectif de ce travail de thèse était de comprendre quels sont les facteurs de contrôle des performances de la déshydratation mécanique des boues d’épuration en filtre-presse et comment ces derniers impactent le fonctionnement du procédé. Dans un premier temps, l’impact des paramètres de fonctionnement des filtres-presses sur leurs performances a été étudié en cellule de filtration tangentielle (cellule de laboratoire reproduisant les processus d’un filtre presse industriel). Ce travail a permis de hiérarchiser les paramètres opératoires selon leur impact sur les performances de déshydratation. Cette étude a permis de mettre en évidence que le paramètre le plus sensible est l’épaisseur de gâteau suivi de la pression. L’impact de ces paramètres est en partie lié à celui du gradient de pression sur les équations de la filtration même si ce dernier doit être considéré en 3D pour expliquer les résultats observés. Dans un second temps l’étude de l’impact des propriétés des boues sur les performances de déshydratation a été réalisée. Pour ce faire, ce travail s’est focalisé sur l’impact d’un des procédés qui modifie le plus les propriétés des boues : la digestion anaérobie. L’objectif de ce travail était d’identifier comment le temps de séjour hydraulique (TSH) appliqué dans le digesteur influence les propriétés physicochimiques des boues et les performances de déshydratation évaluées au travers d’essais de déshydratation en cellule de filtration tangentielle. Cette phase a permis de montrer que quand le TSH augmente de 0 à un TSHcritique, la déshydratabilité de la boue diminue. Au-delà de ce TSHcritique, cette dernière s’améliore sans pour autant atteindre celle de la boue brute. Ces phénomènes ont pu être reliés à une modification des équilibres osmotiques entre les flocs et le milieu interstitiel couplée à une modification de la matrice d’exopolymères solubles des flocs. Enfin, un modèle numérique permettant de simuler la déshydratation des boues résiduaires a été implémenté sous COMSOL multiphysics®. Au travers des processus modélisés, il prend en compte les principaux facteurs de contrôle des performances identifiés auparavant. Après ajustement des paramètres sur un unique essai de déshydratation à une pression donnée, le modèle permet de prédire la siccité du gâteau pour une pression comprise entre 3 et 15 bars. / As more and more sewage sludge are generated, understanding and optimization of mechanical dewatering processes is crucial. Their performances affect both plant management and its environmental and economic impacts. Indeed, dryness of dewatered sludge strongly impacts processes for agronomic and energetic recovery (composting, direct agricultural recycling, incineration ...) and their direct and indirect environmental impacts (volumes to transport...). In addition, the filtrates have to be treated by the wastewater treatment plant, and their composition significantly affects its operating. Filter presses are one of the most common mechanical dewatering processes operated for sludge treatment in wastewater treatment plant. Their performance depends on their operating parameters and sludge properties. However, current knowledge is insufficient (1) to explain why some sludges are easier or harder to dewater than others, and (2) to link these phenomena to processes that carry out during the mechanical dewatering. Hence, dewatering works like a black box from which it is difficult to predict the efficiency of a dewatering tool performed with a particular sludge and to anticipate operating problems. In this context, the objective of this thesis was to understand witch factors drive the efficiency of mechanical dewatering of sewage sludge in the filter press and how they impact the process. First, the impact of operating parameters of filter presses on their efficiency was investigated in cross-flow filtration cell (lab-scale cross-flow filtration cell reproducing processes that occur in an industrial filter press). This work allowed the classification of the operating parameters according to their impact on the dewatering performances. This study highlighted that the most sensitive parameter is the cake thickness followed by pressure. The impact of these parameters is partially linked with their influence on the pressure gradient even if it should be considered in 3D to explain the results. Secondly, the study of the impact of sludge properties on dewatering performances was carried out. In this thesis, this work focuses on the impact of one of the processes which modifies most significantly sludge properties: anaerobic digestion. The objective of this work was to identify how hydraulic retention time (HRT) in the digester affects physicochemical properties of sludge and dewatering performance. Results demonstrated that when the HRT increases from 0 to a critical HRT (HRTcritical), sludge dewaterability decreases. Beyond this HRTcritical, it increases without reaching cake dryness of the raw sludge. These phenomena could be linked to a change in osmotic balance between the flocs and the bulk solution, combined with a modification of the soluble exopolymer matrix of flocs. Finally, a numerical model, allowing the simulation of sludge dewatering was implemented with COMSOL multiphysics®. Equation system takes into account the main factors that affect performances previously identified. After parameter calibration on a single dewatering experiment at 8 bars, the model allows the prediction of cake dryness for any pressure between 3 and 15 bars.

Mature fine tailings (MFT), as a mixture of residual bitumen, sand, silt, fine clay particles and water, are a byproduct of oil sands extraction. The large volume, and poor consolidation and water release ability of MFT have been causing significant economic and environmental concerns. Therefore, several studies have been implemented on finding innovative dewatering/disposal techniques. As a result, different methods have been introduced and tested at a laboratory or a field scale, yet very few of these are commercially used in the oil sands industries. Despite the extensive research, an optimal solution has not been found due to the lack of technical or economic feasibility. In the present study, a novel approach that consists of the rapid dewatering of MFT by using a super absorbent polymer (SAP) to produce dense MFT is proposed. A comprehensive laboratory investigation on the geotechnical characteristics and behavior before and after treatment of MFT is conducted. The effects of SAP based dewatering and freeze/thaw cycles on the undrained shear strength of dewatered MFT by using a vane shear apparatus are studied. Furthermore, the ability of recycled SAP to dewater and densify MFT is assessed. Finally, this study provides the results of consolidation and hydraulic conductivity testing to evaluate the void ratio versus effective stress and hydraulic conductivity of MFT. The effects on the behavior and characteristics of MFT after amendment with usage of recycled SAP are also investigated. The results indicate that SAP has the ability to significantly dewater, densify and increase the undrained shear strength of MFT. Furthermore, when subjected to freeze/thaw cycles, the MFT dewatered with SAP shows an additional increase in strength and solid content. It is also found to be possible to regenerate the polymer (still within sachets) through light thermal drying, and the regenerated SAP can still significantly dewater and thus increase the shear strength and solid content of the MFT. In addition, the obtained high solid content affects and improves the compressibility of the material, thus resulting in low initial void ratios. On the other hand, low hydraulic permeability that is derived from low initial void ratios and consolidation is improved by the freeze/thaw process due to the interconnected voids created during the freezing process.

Dewatering and desalination of building constructions is currently a discussed topic. At the present time, different techniques for dewatering and desalination can be used. The existing methods are efficient but it is necessary to improve these methods and to develop new ones. The moisture in the building constructions is directly connected with the salts, which can be dissolved in it and together with the moisture further to move. The salts can cause damage of constructions and change mechanical and physical properties of the buildings materials. The basic demands for dewatering and desalination are the speed, efficiency and economical factors. Presented dissertation focuses on dewatering and desalination with the use of electrokinetic methods together with the technique of the clay poultices. In the first part of the thesis, basic theoretical principles of moisture and salts are described. In the second part (experimental part), the series of experimental measurements were conducted both in the laboratory and in situ. In this part of dissertation, I was dewatering and desalinating bricks and sandstones under an applied electric field. The main focus was on the optimization of a laboratory setup in order to get the highest efficiency for dewatering and desalination. Other measurements were done in situ, where the same technique was used.

The thesis deals with the technical and economic comparison of technologies for wastewater treatment plants 50-2000 PE based on the processing of selected data ownership and operational records (VÚME, VÚPE) for the years 2013-2015 provided by the Ministry of Agriculture of the Czech Republic. The first section presents an overview of the most important laws and standards of the Czech Republic for water management, describes the characteristics of municipalities to 2,000 inhabitants and operation of wastewater treatment plants up to 2000 PE.The second part evaluates the influence of different types of drainage systems on the quality of wastewater and the efficiency of wastewater treatment. Furthermore, this section deals with the influence of technical and economic comparison of the influence of sludge management concept.In the last part I work with studies and generators for calculating the cost of sludge treatment in larger WWTP, possibly for sludge dewatering and storage.