L'objectif principal de ce travail de thèse concerne l'étude de l' élimination de la DCO et de la nitrification dans une nouveau lit bactérien Multi-Section ( MSB ) . Après une caractérisation de l’hydrodynamique et du transfert d’oxygène de ce lit bactérien, les expériences biologiques menées sous des conditions opératoires contrastées (fortes et faibles charges organiques eteaux usées contenant ou pas des matières particulairs) ont été menées. En parallèle, des simulations avec le logiciel Biowin® ont été réalisées. Les principaux résultats sont résumés en suivant :- La rétention de liquide statique est majoritaire par rapport à la rétention dynamique que ce soit en présence ou en absence de biofilm. Le biofilm joue le rôle d’une "éponge" permettant un maintien de l’humidité du lit même à faible débit. Les expériences de DTS ont montré que le biofilm accroit le temps de séjour du liquide et conduit à une diminution de l’épaisseur du film liquide permettant ainsi de promouvoir le transfert de l'oxygène.- Le réacteur MSB montre une élimination efficace de la DCO (> 95 % ) et de la nitrification ( > 60 % de l’azote entrant), mais une accumulation de DCO particulaire a lieu dans le filtre ce qui conduira à un colmatage à terme. La nitrification cohabite avecl’élimination de la DCO même dans la première section et pour une charge organique élevée ce qui implique une bonne capacité d’oxygénation du MSB par l’aération naturelle.- Un modèle dynamique de MSB a été utilisé implémenté sur le simulateur - BioWin , afin d'obtenir la répartition des biomasses au sein du réacteur et d'évaluer le processus limitant dans chaque section. Le modèle partiellement calibré peut aider à estimer les besoins minimum d'oxygène pour la nitrification et peut rendre compte de la compétition entre la croissance hétérotrophe et la nitrification. / The main objective of this PhD work focused on the study of the COD removal and nitrification in a new designed Multi-Section Bioreactor (MSB). Hydrodynamic characterization of the reactor, biological experiments under contrasted conditions and simulations by Biowin® software were carried out:- Firstly, it was found that static liquid retention is the predominant part both without and with the presence of biofilm. Biofilm acts like a "sponge". RTD experiments showed that biofilm can promote liquid residence time, decrease the liquid film andpromote the oxygen transfer consequently.- Secondly, the MSB operated at contrasted organic loading rate (OLRs) and nitrogen loading rate (NLRs) showed that COD can be effectively removed (removal efficiency > 95%) and nitrification (> 60% of the N removal) occurred in this biofilter.Nitrification is efficient even in the first section implying no drastic oxygen limitation though only natural aeration is occurring.- Thirdly, a TF dynamic model has been used from a simulator - BioWin, in order to get more insights on the biomass distribution in the pilot and to assess the limiting process in each section of the bioreactor. Calibration of the model can help us to estimate theminimum oxygen requirement for nitrification for each zone inside the pilot and it can well represent the competition between heterotrophic growth and nitrification.

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

Esta pesquisa enfoca a avaliação do desempenho de nova configuração de unidade para tratamento biológico de esgoto sanitário por processo combinado, visando à remoção de nutrientes, especialmente nitrogênio. O sistema construído em escala piloto tem volume útil igual a 71,48 litros. Nesta nova configuração de reatores para tratamento terciário de esgoto sanitário, utilizaram-se três reatores sobrepostos, sendo: um reator UASB - “Upflow Anaerobic Sludge Blanket”; um reator de leito móvel e filme fixo aeróbio (com aplicação de oxigênio puro); e, um reator de leito móvel e filme fixo com ambiente anóxico. O material suporte utilizado nos reatores de leito móvel e filme fixo constituiu alternativa inédita no tratamento de efluentes líquidos. Foram utilizadas cavilhas “ranhuradas” de madeira, de dimensões aproximadas de 8,0 mm de diâmetro por 8,0 mm de comprimento. O desempenho geral do sistema quanto à remoção de matéria carbonácea e compostos nitrogenados, e as associações microbianas formadas nos três reatores são objetos principais de estudo deste trabalho. Foram obtidos resultados de remoção de DQO e de nitrogênio bastante satisfatórios, sobretudo quando o tempo de detenção hidráulica total esteve próximo a 20 horas, incluindo o compartimento de decantação (94,6 % para DQO; e 96,7 % para N-NTK, com formação de nitrato em concentrações inferiores a 10,0 mgN-NO3-/l). O TDH estudado variou entre 5 e 24 horas para os sistema completo. O estudo dos consórcios de microrganismos forneceu excelentes resultados quanto à quantidade, diversidade, e atividade das populações desenvolvidas nos diferentes ambientes, confirmando o bom desempenho do sistema e o fornecimento de ambiente adequado para o desenvolvimento das diferentes populações nos três reatores. A idealização desta configuração tem como finalidade realização de tratamento de esgoto sanitário até nível terciário em planta compacta, podendo ser utilizada por pequenas e grandes comunidades, devido à possibilidade de se construir diversos módulos do sistema proposto. / This research is focused on the performance evaluation of a new system configuration of combined biological reactors, treating domestic wastewater till tertiary level. The pilot scale proposed system had a total useful volume of 71,48 liters. This new configuration involves three types of superposed reactors: an Upflow Anaerobic Sludge Blanket reactor; an aerobic fixed film mobile bed reactor (fed with pure oxygen); and a fixed film mobile bed reactor at anoxic environment. The support material used inside the fixed film mobile bed reactors was wood made grooved dowels. The main purposes of this work are to evaluate the systems general performance regarding COD and nitrogen removal, and the microbial associations inside the reactors. It reached quite satisfactory results regarding COD and nitrogen removal when the total hydraulic retention time (HRT) was around 20 hours, including the clarification zone volume (94,6 % for the COD; and 96,7 % for the TKN-N, whit nitrate formation below 10,0 mgN-NO3-/l). HRTs from 5 to 20 hours were studied. The microbial associations were present in large number, with a great diversity and high specific activities at the different environments, confirming the good results obtained and the suitable environment provided for the growth of the different populations inside the three reactors. The idealization of this treatment system has the goal to treat domestic wastewater from small to large communities till tertiary level, in compact treatment plants, due to the possibility of constructing several modules of the system.

Eutrophication is an expanding issue due to the increase of human-induced nitrogen leakage from agriculture. Eutrophication can lead to severe environmental problems such as exaggerated algal bloom and oxygen deprivation in water courses. One approach to clear away nitrogen is to use constructed wetlands. Wetlands have the ability to clean the water that flows through it by biological, chemical and physical reactions. The aim of this study is to determine if a deep or shallow wetland is more advantageous in removing nitrogen and how phosphor addition affects nitrogen removal. The method used was analysis of concentrations of nitrate, nitrite (NO3- + NO2-) and phosphorous from the years 2018 and 2019 from an experimental wetland in Halmstad, Sweden, and carrying out a quantitative experimental study. The results showed that NO3- + NO2- removal was higher in deeper wetlands for both years and for the removal rate coefficients in 2019. Ponds with phosphorus addition had an increase in NO3- + NO2- removal. The research conclusion was that the deeper wetlands are more efficient at removing nitrogen than shallow. Phosphorous addition increases the nitrogen removal in both shallow and deep ponds. Shallow wetlands might have potential to become superior compared to deep wetlands when the vegetation and bacteria establish. This statement however requires further research. / 42 % av människorelaterade kväveutsläpp kommer från jordbruket av bland annat gödsling och plöjning av mark. Dessa emissioner kan leda till ett flertal miljöproblem som övergödning och syrebrist i närliggande vattenområden. Ett sätt att minska kväveutsläppet från jordbruken kan vara att använda sig av konstruerade våtmarker. Syftet med denna studie är att undersöka om en våtmark med högre eller lägre djup är mest effektiv på att avskilja kväve. Det ska också granskas om fosfortillsats påverkar kväveborttagningen i både grunda och djupa dammar. Frågeställningarna i studien är: Är djupa eller grunda dammar mest effektiva på att avskilja kväve? Hur påverkar fosfortillsats dammarnas förmåga att avskilja kväve? Vilken typ av damm är mest kostnadseffektiv? För att besvara de tre frågeställningarna utfördes en kvantitativ studie. Metoden delades in i 4 delar: fältarbete, laboratorium, databearbetning och datainsamling. Av dessa 4 var databearbetning den huvudsakliga beståndsdelen i resultatet där NO3 -+ NO2 - koncentrationer behandlades i flera formler för att få fram koncentrationsskillnaden, procentuella borttagningen och areella borttagningskoefficienten. Resultatet som genererades visade att för 2018 och 2019 var de effektivaste dammarna de djupa med fosfortillsats. Fosfortillsats minskade upptaget av kväve för grunda dammar i 2018, men ökade upptaget för både djupa och grunda dammar för 2019. När kväveavskiljningen relaterades till yta och temperatur för 2019 blev skillnaden mellan djupa och grunda avsevärt mindre. Sammanfattningsvis blev slutsatsen i arbetet att djupa dammar med fosfortillsats är effektivast. Från beräkningarna av den areella borttagningskoefficienten kan man se en möjlighet för grunda dammar att bli ännu effektivare än djupa när deras överlägsna vegetation och bakterietillväxt väl etablerat sig. På grund av att skillnaden är minimal mellan djupa och grunda dammar är det möjligt att den mest kostnadseffektiva dammen är en grund sådan.

Thesis (PhD (Chemical Engineering))--Cape Peninsula University of Technology, 2019 / Simultaneous nitrification and aerobic denitrification (SNaD) is a preferred method for single stage total nitrogen (TN) removal, which was recently proposed to improve wastewater treatment plant design. However, SNaD processes are prone to inhibition by toxicant loading with free cyanide (CN-) possessing the highest inhibitory effect on such processes, rendering these processes ineffective. Despite the best efforts of regulators to limit toxicant disposal into municipal wastewater sewage systems (MWSSs), free cyanide (CN-) still enters MWSSs through various pathways; hence, it has been suggested that CN- resistant or tolerant microorganisms be utilized for processes such as SNaD. To mitigate toxicant loading, organisms in SNaD have been observed to adopt a multiphase growth strategy to sequentially degrade CN- during primary growth and subsequently degrade TN during the secondary growth phase. However, CN- degrading microorganisms are not widely used for SNaD in MWSSs due to the inadequate application of suitable microorganisms (Chromobacterium violaceum, Pseudomonas aeruginosa, Thiobacillus denitrificans, Rhodospirillum palustris, Klebsiella pneumoniae, and Alcaligenes faecalis) commonly used in single-stage SNaD. The use of CN- degrading or resistant microorganisms for SNaD is a cost-effective method compared to the use of other methods of CN- removal prior to TN removal, as they involve multi-stage systems (as currently observed in MWSSs). The use of CN- degrading microorganisms, particularly when used as a consortium, presents a promising and sustainable resolution to mitigate inhibitory effects of CN- in SNaD. However, SNaD is known to be completely inhibited by CN- thus it is imperative to also study some thermodynamic parameters of SNaD under high CN- conditions to see the feasibility of the process. The Gibbs free energy is significant to understand the feasibility of SNaD, it is also vital to study Gibbs free energy to determine whether or not the biological reaction is plausible. The relationship between the rate of nitrification and Gibbs free energy was also investigated. The attained results showed that up to 37.55 mg CN-/L did not have an effect on SNaD. The consortia degraded CN- and achieved SNaD, with degradation efficiency of 92.9 and 97.7% while the degradation rate of 0.0234 and 0.139 mg/L/hr for ammonium-nitrogen (NH4-N) and CN- respectively. Moreover, all the free Gibbs energy was describing the individual processes were found to be negative, with the lowest Gibbs free energy being -756.4 and -1830.9 Kcal/mol for nitritation and nitratation in the first 48 h of the biological, reaction respectively. Additionally, a linear relationship between the rate of NH4-N and nitrite-nitrogen (NO2-N) degradation with their respective Gibbs free energy was observed. Linear model was also used to predict the relationship between NH4-N, NO2-N degradation and Gibbs free energy. These results obtained showed a good correlation between the models and the experimental data with correlation efficiency being 0.94 and 0.93 for nitritation, and nitratation, respectively. From the results found it can be deduced that SNaD is plausible under high cyanide conditions when cyanide degrading or tolerant microorganisms are employed. This can be a sustainable solution to SNaD inhibition by CN- compounds during wastewater treatment. Furthermore, a single strain was purified from the consortium and identified as Acinetobacter courvalinii. This bacterial strain was found to be able to perform sequential CN- degradation, and SNaD; an ability associated with multiphase growth strategy of the microorganism when provided with multiple nitrogenous sources, i.e. CN- and TN. The effect of CN- on nitrification and aerobic denitrification including enzyme expression, activity and protein functionality of Acinetobacter courvalinii was investigated. It was found that CN- concentration of up to 5.8 mg CN-/L did not affect the growth of Acinetobacter courvalinii. In cultures whereby the A. courvalinii isolate was used, degradation rates of CN- and NH4-N were found to be 2.2 mg CN-/L/h and 0.40 mg NH4-N/L/h, respectively. Moreover, the effect of CN- on NH4-N, nitrate-nitrogen (NO3-N) and NO2-N oxidizing enzymes was investigated, with findings indicating CN- did not affect the expression and activity of ammonia monooxygenase (AMO), but affected the activity of nitrate reductase (NaR) and nitrite reductase (NiR). Nevertheless, a slow decrease in NO2-N was observed after the addition of CN- thus confirming the activity of NaR and the activation of the denitrification pathway by the CN-. Moreover, five models’ (Monod, Moser, Rate law, Haldane, and Andrew’s model) ability to predict SNaD under CN- conditions, indicated that only Rate law, Haldane and Andrew’s models, were suited to predict both SNaD and CN- degradation. Due to low degradation rates of NH4-N and CN-, optimization of SNaD was essential. Therefore, response surface methodology was used to optimize the SNaD under CN- conditions. The physiological parameters that were considered for optimization were temperature and pH; with the result showing that the optimum for pH and temperature was 6.5 and 36.5oC respectively, with NH4-N and CN- degradation efficiency of 50 and 80.2%, respectively. Furthermore, the degradation kinetics of NH4-N and CN- were also studied under the optimum conditions in batch culture reactors, and the results showed that up to 70.6% and 97.3% of NH4-N and CN- were simultaneously degraded with degradation rates of 0.66 and 0.41 mg/L/h, respectively. The predictive ability of RSM was further compared with cybernetic models, and cybernetic models were found to better predict SNaD under CN- conditions. These results exhibited a promising solution in the management of inhibition effected of CN- towards SNaD at an industrial scale.

En aquesta tesi es presenten dues propostes de Sistemes de Control basats en Lògica Difusa (SCLD), des del seu disseny fins a la seva implementació i validació en dues instal·lacions: l'EDAR Granollers i l'EDAR Taradell.El capítol 1 explica els conceptes bàsics per comprendre el desenvolupament dels dos SCLD i el resum d'una revisió d'articles que relacionen la lògica difusa amb aigües residuals. A continuació, s'estableixen els objectius. En el capítol 3 es presenten els materials i mètodes. Els capítols 4 i 5 exposen el treball realitzat per arribar a la implementació dels dos SCLD. Ambdós capítols presenten la mateixa estructura: presentació, definició dels objectius del SCLD, descripció de l'EDAR on s'implementa el SCLD, desenvolupament d'índexs d'avaluació, explicació del disseny del SCLD i la seva avaluació mitjançant estudis de simulació, implementació i validació del SCLD a l'EDAR i, finalment discussió del treball realitzat. En el capítol 6 s'enumeren les conclusions obtingudes. / This thesis presents two proposals of Fuzzy Logic Control Systems (FLCS's), from their design to their implementation and validation in two facilities: Granollers and Taradell WWTP. The fundamental concepts to understand the FLCS's development are explained in the first chapter with a summary of scientific papers related to fuzzy logic applications in the wastewater treatment. The objectives are established in Chapter 2 and the materials and methods are described in Chapter 3.In Chapters 4 and 5, the work to design, implement and validate the FLCS's is presented. Both chapters have the same structure: a presentation, a goal definition of FLCS, a description of the WWTP, the evaluation index development, a detailed explanation about designing the FLCS process and its evaluation by simulation studies, the implementation of FLCS to WWTPs and their validation and, finally, a discussion of the work carried out is presented. The main conclusions are enumerated in Chapter 6.