The Integrated Film Activated Sludge Process (IFAS) was developed to reduce the cost of additional facilities required to complete year round nitrification in the design of new or retrofit wastewater treatment plants. The purpose of this project was to develop a computer-based mechanistic model, called IFAS, which can be used as a tool by scientists and engineers to optimize their designs and to troubleshoot a full-scale treatment plant. The program also can be employed to assist researchers conducting their studies of IFAS wastewater treatment processes. IFAS enables the steady-state simulation of nitrification-denitrification processes as well as carbonaceous removal in systems utilizing integrated media, but this current version supports only sponge type media. The IFAS program was developed by incorporating empirical equations for integrated biofilm carbonaceous uptake and nitrification developed by Sen and Randall (1995) into the general activated sludge model, developed by the International Association on Water Quality (IAWQ, previously known as IAWRC), plus the biological phosphorus removal model of Wentzel et al (1989). The calibration and evaluation of the IFAS model was performed using existing data from both an IFAS system and a conventional activated sludge bench-scale plant operated over a wide range of Aerobic Mean Cell Residence Times (Aerobic MCRT's). The model developed provides a good fit and a reasonable prediction of the experimental data for both the IFAS and the conventional pilot-scale systems. The phosphorus removal component of the model has not yet been calibrated because of insufficient data and the lack of adequately defined parameters. / Master of Science

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-15T11:55:55Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO LAÍSE ALVES CANDIDO.pdf: 1717138 bytes, checksum: 7884517a24d4674909faeecc260c672f (MD5) / Made available in DSpace on 2016-07-15T11:55:55Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO LAÍSE ALVES CANDIDO.pdf: 1717138 bytes, checksum: 7884517a24d4674909faeecc260c672f (MD5) Previous issue date: 2015-12-21 / O objetivo deste estudo foi avaliar a capacidade de previsão do algoritmo ASM2d modificado, utilizando o programa AQUASIM 2.0® após sua calibração para um reator de bateladas sequenciais com adição de fonte externa de carbono para tratamento de esgoto doméstico objetivando a remoção de matéria orgânica, fósforo e nitrogênio. O sistema piloto está instalado na área experimental da UFPE localizada na Estação de Tratamento de Esgotos da Mangueira que recebe os esgotos de uma comunidade de baixa renda da cidade de Recife-PE. O reator tem volume útil de 160 L (cento e sessenta litros) e opera em batelada com ciclos de 08h (oito horas) dividas em: enchimento e fase anaeróbia (120 min), fase aeróbia (260 min), fase anóxica (50 min), sedimentação (45 min) e esvaziamento (5 min). Os comportamentos previstos pelo modelo para as frações de matéria orgânica, de nitrogênio e de fósforo e do oxigênio dissolvido (OD) e taxa de consumo de oxigênio são coerentes com o descrito pela literatura e concordam com os dados medidos durante a fase de operação do reator. No entanto, faz-se necessária sua validação com maiores séries temporais de dados para maximizar sua confiabilidade, assim como é imprescindível que sejam instalados equipamentos para medição do volume de oxigênio adicionado, monitoramento online do OD e da alcalinidade e controle rigoroso do volume e características do lodo descartado e das frações de sólidos em todas as fases da operação do reator. Embora o modelo não tenha tido sua capacidade de previsão dos parâmetros validada, foi possível verificar a aplicabilidade do ASM2d para a configuração de fases escolhida e com temperatura próxima à real. / The objective of this study was to evaluate the modified ASM2d algorithm foresight capacity using the AQUASIM 2.0® program after its calibration for sequencing batch reactor with the addition of external carbon source for domestic sewage treatment aiming at removal of organic matter, phosphorus and nitrogen. The pilot plant is installed at UFPE’s experimental area at the Wastewater Treatment Plant of Mangueira which receives influent from a low-income community in the city of Recife-PE. The reactor has an effective volume of 160 L (one hundred sixty liters) and operates in batch with cycles of 08h (eight hours) divided into: filling and anaerobic stage (120 min), aerobic phase (260 min), anoxic phase (50 min), sedimentation (45 minutes) and emptying (5 min). The behavior predicted by the model for fractions of organic matter, nitrogen and phosphorus, dissolved oxygen (DO) and oxygen uptake rate are consistent with that described in the literature and agree with the measured data during reactor operation phase. However, a validation with larger data time series is necessary to maximize its reliability, as it is indispensable to have installed equipment for measuring oxygen input, online monitoring of DO and alkalinity and strict control of the volume and characteristics of the excess sludge and solid fractions for all phases of reactor operation. Although the model has not had its predictive power validated, it was possible to verify the applicability of ASM2d for the chosen stage setting and at a temperature close to the operational.

Thesis (Master of Environmental Management)--Cape Peninsula University of Technology, 2018. / Fresh water is a renewable resource, but it is also finite, especially given environmental impacts from anthropogenic activities. Globally, there are countless signs that untreated industrial discharge into fresh watercourses is one of the main causes of ecosystem degradation. Poultry slaughterhouse wastewater (PSW) amongst the main pollutants of fresh water sources. In recent years, the world’s pre-eminent researchers have developed innovative wastewater treatment processes to treat the large quantity of wastewater generated as well as to manage the environmental health concerns arising from PSW discharged into the environment. Furthermore, increasing wastewater treatment capital costs and the implementation of increasingly rigorous government legislation to mitigate environmental pollution whilst minimizing fresh water source contamination, requires that wastewater such as PSW, be adequately treated prior to discharge. In order to assist the small-scale poultry producers in South Africa (SA), process simulation for a small-scale poultry slaughterhouse wastewater treatment plant was proposed using Sumo Wastewater treatment plant (WWTP) simulation software. Sumo is an innovative and most versatile wastewater simulation package on the market. The simulator is capable of modelling treatment plants of unlimited complexity, focusing largely on Biochemical oxygen demand (BOD), Chemical oxygen demand (COD), nitrogen and phosphorus removal; with digester, and side streams design options, being available. Considering the possible advantages in modelling and ongoing studies of implementing wastewater treatment to increase water management, anaerobic digestion of high strength wastewater such as PSW, warranted this research study. Model development from the simulation included the evaluation of numerous design options to assist small scale poultry producers, to have a variety of designs to choose from in their PSW WWTP designs. With the aid of Sumo, two models were designed in this study, namely a single-stage and a two-stage anaerobic digestion without a recycle. The PSW used as feed was obtained from a local poultry slaughterhouse (Western Cape, South Africa). Both model designs predicted the reduction of the organic matter (COD, BOD5) total suspended solids (TSS), and volatile suspended solids (VSS) in the PSW. The digester for the single stage anaerobic digestion system modelled was set to operate at steady state for 150 days under mesophilic temperature (35 ˚C) with a solid retention time (SRT) of 25 days. The COD, TSS, VSS and BOD removal efficiencies reached a maximum of 64%, 77%, 84%, and 94%, respectively, at an organic load rate (OLR) of 143.6 mg COD/L/day. A minute increase in the ammonia (NH3) and phosphate (PO3- 4) concentration was observed once the simulation was completed. As for the two-stage anaerobic digestion system, both digesters were set to perform at mesophilic temperatures (35 ˚C) and a SRT of 13 days in the first digester and 25 days in the subsequent digester. The two-stage anaerobic digestion showed better performance in comparison to the single-stage anaerobic digestion system. The COD, TSS, VSS and BOD5 removal efficiencies reached a maximum of 69%, 79%, 85%, and 96%, respectively, at an at an OLR of 143.6 mg COD/L/day. A similar trend regarding phosphate and ammonia removal was noticed in the two-stage anaerobic digestion, suggesting a tertiary treatment system to be in place for further treatment. Although, the two-stage anaerobic digestion demonstrated adequate performance, for the purpose of this study, the single-stage was the process recommended for PSW treatment, as it is less costly and will be suitable for small scale poultry producers; albeit biogas production is much higher when digesters are connected in series. The PSW treatment modelling for this study was successfully employed with the resultant effluent being compliant with the City of Cape Town (CCT) wastewater and industrial effluent by-law discharge limits. Although, both the PO3- 4 and NH3 were suggested to require further monitoring. Therefore, the poultry slaughterhouse from which the PSW was obtained will be able to safely discharge the treated wastewater proposed in this research into local water bodies, i.e. rivers in the Western Cape, SA; however, the treated PSW will not be suitable for re-use as process water.

O presente trabalho avaliou a possibilidade de receber e tratar resíduo de tanques sépticos num sistema dimensionado para tratar esgoto doméstico. Neste sentido, o objetivo deste estudo foi avaliar o co-tratamento deste resíduo numa estação de tratamento de esgoto composta por processo de lodos ativados. Para a realização desta avaliação utilizou-se o modelo matemático ASM1 e o software WRc Stoat 5.0. O modelo ASM1 descreve a remoção de matéria orgânica carbonácea, a nitrificação e a desnitrificação. Para atender ao objetivo proposto, foram realizadas simulações de quatro grupo de cenários, sendo que em cada grupo a ETE operava com uma vazão fixa e foi alterada a parcela de resíduo de tanque séptico a ser tratada no sistema. Para a realização das simulações, previamente realizou-se a estruturação do modelo matemático ao sistema de tratamento selecionado, ajustes dos coeficientes estequiométricos e parâmetros cinéticos e determinaram-se as concentrações de entrada e o fracionamento da DQO e do nitrogênio para o esgoto bruto e para o resíduo de tanque séptico. As simulações geraram como resultado a possibilidade de, num sistema dimensionado para uma vazão média de 180 m3/h e operado com uma vazão de 45 m3/h de esgoto doméstico receber 4,3 m3/h de resíduo de tanque séptico sem comprometer os padrões de lançamento. Já, no caso da mesma ETE operando com 90 m3/h, 135 m3/h e 162 m3/h, as parcelas possíveis de serem recebidas de resíduo de tanque séptico e concomitantemente atendendo aos padrões de lançamento definidos na legislação foram 3,6 m3/h, 3,3 m3/h e 2,9 m3/h. Os resultados obtidos permitem concluir que é viável co-tratar resíduo de tanque séptico com o esgoto doméstico e ao mesmo tempo atender aos padrões de lançamento definidos na legislação, desde que respeitados os fatores limitantes e as cargas máximas. O recebimento e o tratamento do resíduo de tanque séptico em sistemas projetados para esgoto doméstico mostram-se como práticas que podem ser implantados na gestão dos sistemas de esgotamento sanitário. Esta aplicação poderia contribuir para ampliar a correta destinação dos esgotos e consequentemente com a melhoria dos índices de atendimento do esgotamento sanitário. / The present work evaluated the possibility of receiving and treating septic tank residue in a system designed to treat domestic sewage. Therefore, the objective of this study was to evaluate the co-treatment of this residue in a sewage treatment plant with an activated sludge process. The ASM1 model and software WRc Stoat 5.0 were used to perform this evaluation. The ASM1 model describes the removal of carbonaceous organic matter, nitrification and denitrification processes. To attend the proposed objective, simulations of four scenarios group were realized and in each group the system operated with a fixed flow and was changed the portion of septic tank residue. Before running the simulations, the mathematical model was structured to the selected treatment system, adjustments of the stoichiometric coefficients and kinetic parameters and were determined the inputs and fractionations concentration of the COD and nitrogen for the sewage and the septic tank residue. The simulation results show that is possible, in a system designed for an average flow of 180 m3/h and underloaded with a domestic sewage flow of 45 m3/h to receive 4.3 m3/h of septic tank residue without compromising the standards. For systems operating at 90 m3/h, 135 m3/h and 162 m3/h, the possible parcels to be received from septic tank residue without compromising standards defined in the legislation were, respectively, 3.6 m3/h, 3.3 m3/h and 2.9 m3/h. The results allow the conclusion that it is feasible to co-treat septic tank residue with domestic sewage and at the same time respect the standards defined in the legislation, once the limiting flowrates and maximum loads are respected. The acceptance and treatment of septic tank residue in systems designed for domestic sewage are practices that can be implemented in the management of sanitary sewage systems. That can be enplaned to improve the management of sewage systems, therefore, expanding the correct destination of wastewater and consequently contribute to the improvement of sanitary sewage index.

O presente trabalho avaliou a possibilidade de receber e tratar resíduo de tanques sépticos num sistema dimensionado para tratar esgoto doméstico. Neste sentido, o objetivo deste estudo foi avaliar o co-tratamento deste resíduo numa estação de tratamento de esgoto composta por processo de lodos ativados. Para a realização desta avaliação utilizou-se o modelo matemático ASM1 e o software WRc Stoat 5.0. O modelo ASM1 descreve a remoção de matéria orgânica carbonácea, a nitrificação e a desnitrificação. Para atender ao objetivo proposto, foram realizadas simulações de quatro grupo de cenários, sendo que em cada grupo a ETE operava com uma vazão fixa e foi alterada a parcela de resíduo de tanque séptico a ser tratada no sistema. Para a realização das simulações, previamente realizou-se a estruturação do modelo matemático ao sistema de tratamento selecionado, ajustes dos coeficientes estequiométricos e parâmetros cinéticos e determinaram-se as concentrações de entrada e o fracionamento da DQO e do nitrogênio para o esgoto bruto e para o resíduo de tanque séptico. As simulações geraram como resultado a possibilidade de, num sistema dimensionado para uma vazão média de 180 m3/h e operado com uma vazão de 45 m3/h de esgoto doméstico receber 4,3 m3/h de resíduo de tanque séptico sem comprometer os padrões de lançamento. Já, no caso da mesma ETE operando com 90 m3/h, 135 m3/h e 162 m3/h, as parcelas possíveis de serem recebidas de resíduo de tanque séptico e concomitantemente atendendo aos padrões de lançamento definidos na legislação foram 3,6 m3/h, 3,3 m3/h e 2,9 m3/h. Os resultados obtidos permitem concluir que é viável co-tratar resíduo de tanque séptico com o esgoto doméstico e ao mesmo tempo atender aos padrões de lançamento definidos na legislação, desde que respeitados os fatores limitantes e as cargas máximas. O recebimento e o tratamento do resíduo de tanque séptico em sistemas projetados para esgoto doméstico mostram-se como práticas que podem ser implantados na gestão dos sistemas de esgotamento sanitário. Esta aplicação poderia contribuir para ampliar a correta destinação dos esgotos e consequentemente com a melhoria dos índices de atendimento do esgotamento sanitário. / The present work evaluated the possibility of receiving and treating septic tank residue in a system designed to treat domestic sewage. Therefore, the objective of this study was to evaluate the co-treatment of this residue in a sewage treatment plant with an activated sludge process. The ASM1 model and software WRc Stoat 5.0 were used to perform this evaluation. The ASM1 model describes the removal of carbonaceous organic matter, nitrification and denitrification processes. To attend the proposed objective, simulations of four scenarios group were realized and in each group the system operated with a fixed flow and was changed the portion of septic tank residue. Before running the simulations, the mathematical model was structured to the selected treatment system, adjustments of the stoichiometric coefficients and kinetic parameters and were determined the inputs and fractionations concentration of the COD and nitrogen for the sewage and the septic tank residue. The simulation results show that is possible, in a system designed for an average flow of 180 m3/h and underloaded with a domestic sewage flow of 45 m3/h to receive 4.3 m3/h of septic tank residue without compromising the standards. For systems operating at 90 m3/h, 135 m3/h and 162 m3/h, the possible parcels to be received from septic tank residue without compromising standards defined in the legislation were, respectively, 3.6 m3/h, 3.3 m3/h and 2.9 m3/h. The results allow the conclusion that it is feasible to co-treat septic tank residue with domestic sewage and at the same time respect the standards defined in the legislation, once the limiting flowrates and maximum loads are respected. The acceptance and treatment of septic tank residue in systems designed for domestic sewage are practices that can be implemented in the management of sanitary sewage systems. That can be enplaned to improve the management of sewage systems, therefore, expanding the correct destination of wastewater and consequently contribute to the improvement of sanitary sewage index.

O presente trabalho avaliou a possibilidade de receber e tratar resíduo de tanques sépticos num sistema dimensionado para tratar esgoto doméstico. Neste sentido, o objetivo deste estudo foi avaliar o co-tratamento deste resíduo numa estação de tratamento de esgoto composta por processo de lodos ativados. Para a realização desta avaliação utilizou-se o modelo matemático ASM1 e o software WRc Stoat 5.0. O modelo ASM1 descreve a remoção de matéria orgânica carbonácea, a nitrificação e a desnitrificação. Para atender ao objetivo proposto, foram realizadas simulações de quatro grupo de cenários, sendo que em cada grupo a ETE operava com uma vazão fixa e foi alterada a parcela de resíduo de tanque séptico a ser tratada no sistema. Para a realização das simulações, previamente realizou-se a estruturação do modelo matemático ao sistema de tratamento selecionado, ajustes dos coeficientes estequiométricos e parâmetros cinéticos e determinaram-se as concentrações de entrada e o fracionamento da DQO e do nitrogênio para o esgoto bruto e para o resíduo de tanque séptico. As simulações geraram como resultado a possibilidade de, num sistema dimensionado para uma vazão média de 180 m3/h e operado com uma vazão de 45 m3/h de esgoto doméstico receber 4,3 m3/h de resíduo de tanque séptico sem comprometer os padrões de lançamento. Já, no caso da mesma ETE operando com 90 m3/h, 135 m3/h e 162 m3/h, as parcelas possíveis de serem recebidas de resíduo de tanque séptico e concomitantemente atendendo aos padrões de lançamento definidos na legislação foram 3,6 m3/h, 3,3 m3/h e 2,9 m3/h. Os resultados obtidos permitem concluir que é viável co-tratar resíduo de tanque séptico com o esgoto doméstico e ao mesmo tempo atender aos padrões de lançamento definidos na legislação, desde que respeitados os fatores limitantes e as cargas máximas. O recebimento e o tratamento do resíduo de tanque séptico em sistemas projetados para esgoto doméstico mostram-se como práticas que podem ser implantados na gestão dos sistemas de esgotamento sanitário. Esta aplicação poderia contribuir para ampliar a correta destinação dos esgotos e consequentemente com a melhoria dos índices de atendimento do esgotamento sanitário. / The present work evaluated the possibility of receiving and treating septic tank residue in a system designed to treat domestic sewage. Therefore, the objective of this study was to evaluate the co-treatment of this residue in a sewage treatment plant with an activated sludge process. The ASM1 model and software WRc Stoat 5.0 were used to perform this evaluation. The ASM1 model describes the removal of carbonaceous organic matter, nitrification and denitrification processes. To attend the proposed objective, simulations of four scenarios group were realized and in each group the system operated with a fixed flow and was changed the portion of septic tank residue. Before running the simulations, the mathematical model was structured to the selected treatment system, adjustments of the stoichiometric coefficients and kinetic parameters and were determined the inputs and fractionations concentration of the COD and nitrogen for the sewage and the septic tank residue. The simulation results show that is possible, in a system designed for an average flow of 180 m3/h and underloaded with a domestic sewage flow of 45 m3/h to receive 4.3 m3/h of septic tank residue without compromising the standards. For systems operating at 90 m3/h, 135 m3/h and 162 m3/h, the possible parcels to be received from septic tank residue without compromising standards defined in the legislation were, respectively, 3.6 m3/h, 3.3 m3/h and 2.9 m3/h. The results allow the conclusion that it is feasible to co-treat septic tank residue with domestic sewage and at the same time respect the standards defined in the legislation, once the limiting flowrates and maximum loads are respected. The acceptance and treatment of septic tank residue in systems designed for domestic sewage are practices that can be implemented in the management of sanitary sewage systems. That can be enplaned to improve the management of sewage systems, therefore, expanding the correct destination of wastewater and consequently contribute to the improvement of sanitary sewage index.

Les règlements plus stricts pour les rejets d'eaux usées présentent de nouveaux défis technologiques pour le traitement d'eaux usées urbaines et industrielles. Le besoin notamment d‘améliorer la qualité hygiénique de l'eau traitée se fait ressentir en cas de sites sensibles ou de réutilisation. Le bioréacteur à membranes (BRMs) représente une des approches les plus innovatrices pour éviter la présence d'agents pathogènes dans l‘eau en sortie de station. En utilisant des membranes avec un seuil de coupure dans la gamme 0.04~0.2 μm, les bactéries mais aussi les virus sont pratiquement complètement retenus. Si l'encrassement membranaire reste un problème déterminant pour le développement des BRMs, le manque d‘outils de caractérisation en ligne de la qualité et la quantité de biomasse active dans les réacteurs reste un point important pour favoriser le contrôle et l‘optimisation des BRMs. Dans cette étude une méthode originale a été développée pour évaluer la viabilité des boues activées présentes dans un réacteur biologique d‘épuration en complémentarité des informations données par la mesure d'activité respirométrique. Cette méthode permet la distinction entre cellule morte et vivante, la respirométrie pouvant alors distinguée la part active de la biomasse vivante. Le travail expérimental a été conduit dans deux réacteurs biologiques de type chenal d‘oxydation équipés de membranes immergées "airlift oxidation ditch membrane bioreactor" (AOXMBR). Les modules membranaires sont immergés dans un zone aérée où l‘apport d‘air permet à la fois la circulation d‘eau par air-lift, l‘aération du milieu et le nettoyage des membranes par aération. Les essais ont été conduits en mode fermé (batch reactor), alterné (fed batch reactor) et continu. La première partie de l‘étude concerne la caractérisation hydrodynamique du réacteur déterminante en terme de conformité du système pour la circulation des fluides, l‘intensité des transferts et des réactions d‘épuration. Les résultats mettent en avant le rôle de la géométrie de l‘airlift sur la circulation des fluides mais aussi la rétention gazeuse déterminante en terme de transfert d‘oxygène et capacité de nettoyage des membranes. La viabilité et l'activité respirométrique de boues activée ont alors été étudiées sous différentes conditions opératoires. Les résultats ont montré une évolution semblable des deux paramètres en fonction des conditions imposées. Ceci confirme l‘intérêt de la mesure de viabilité qui peut être conduite en ligne sur le système, à la différence de la mesure par respirométrie qui nécessite une procédure spécifique plus ou moins complexe. Toutefois, les essais ont montré aussi qu‘une concentration en biomasse importante était nécessaire dans le bioréacteur pour que la viabilité soit mesurable. Les résultats ont aussi montré que la viabilité et l'activité augmentent avec la charge organique (Cv). Cette variation était conforme à l'augmentation des matières volatiles en suspension MVS et de la vitesse de consommation d‘oxygène OUR. Lors de diminution de charge organique, la concentration de protéine dans le milieu a changé inversement avec la viabilité de la biomasse. De possibles améliorations de l'instrument de mesure en ligne de la viabilité et de l'activité de boues activées dans les bioréacteurs sont également discutées. Les performances épuratives mesurées ont confirmé la grande capacité épuratoire d‘un BRM, toutefois, travailler à très forte charge engendre une dynamique de colmatage intense qu‘il faut maîtriser. / In this study a novel method was developed to assess the viability of activated sludge present in a biological treatment process and signify its complementarity from respirometric activity. This method allows the distinction between viable vs. dead and inactive vs. active microbial cells in biomass population and can be used for a better and more efficient control of the biological activity especially in MBR systems.For this purposed two airlift oxidation ditch membrane bioreactors (AOXMBR), were designed and constructed. They were equipped with flat sheet, membranes directly immersed in the airlift section where the air injection induced sludge aeration, water circulation and continuous membrane cleaning.To evaluate the relevance of the batch, fed-batch and AOXMBR) were carried out in order to obtain a better understanding of biomass characteristic for MBR performance.Firstly, for determining the treatment capacity of the proposed AOXMBR is important to understanding of the hydrodynamic characteristics of the system. And impact of design parameter on hydrodynamic characterization of the system was investigated. The results showed the gas holdup and liquid velocity increased with increase in superficial gas velocity and decrease in distance from aeration zone. Furthermore, gas holdup and liquid velocity in downcomer section did not show any significant variations with change in the top to bottom clearance ratio. The riser gas holdup data was related to the superficial gas velocity and the top to bottom clearance ratio data. Also, the downcomer gas holdup was related to superficial gas velocity and distance from airlift section.Secondly, viability and respirometric activity of activated sludge under different activated sludge conditions (batch, fed-batch) at high cell density as the model of membrane bioreactors were investigated. The results showed the same downward trend for both these parameters (viability and respirometric activity) which was due to quantitative and qualitative changes in the microbial culture in the activated sludge. Based on different fed of substrate for each experimental run (batch, fed-batch), operational variables showed significant influence in viability and activity of activated sludge. Also, the effect of changing physicochemical condition.on viability and respirometric activity was investigated. The results showed that respirometric activity was affected more strongly by temperature than viability.Thirdly, biological performance of AOXMBR was carried out.Finally, base on data obtained in the last experiment, in this part the capacitance sensor used as the on-line monitoring of viability of activated sludge in AOXMBR. Results showed that viability and activity were increased with organic loading rate (OLR) increasing until 5 kg COD m-3 d-1. This variation was in accordance with increasing of MLSS, MLVSS and OUR. The results also showed that the viability of biomass decreased when reducing the organic loading rate from 5 to 4 kg COD m-3 d-1. Also, protein concentration in system changed inversely with activated sludge viability.The possible reasons are discussed for future improvements online instrument for measuring viability and activity of activated sludge in biological wastewater. Summary of the principal results and novelty of this thesis obtained in this study: The porposed system would reward improved efficiency across the oxidation ditch, airlift and membrane bioreactor. The AXOMBR is a suitable system for operating at high organic laoding rate. However, the suddenly reduction of OLR affects on viability of activated sludge. The specific characterization of the system is capable of working at three different zone: aerobic, anoxic and anaerobic zone. Also, the time of operating at each zone can be changed with superficial gas velocity top to bottom clearance.

Le surcoût de fonctionnement d'un BRM immergé a pour origine essentielle la dépense d'énergie liée à la maîtrise de la perméabilité membranaire par aération. La littérature montre les liens qui existent entre concentration en biomasse dans le réacteur et présence de produits microbiens solubles liés à l'activité bactérienne. Réduire la demande en énergie signifie réduire l'aération membrane, voire l'aération process liée aux besoins en oxygène des populations épuratrices. Pour ce faire, il est donc déterminant de réduire l'activité biologique au sein du réacteur sans pour autant dégrader la qualité de l'eau traitée. Pour répondre à ce défi, il a été proposé de développer un BRM en association avec un prétraitement physico-chimique dont le rôle est de retenir une grande part de la matière organique (mais aussi probablement les phosphates), le BRM n'a alors pour rôle que de traiter le résiduel de matière organique et d'éliminer les composés azotés peu retenus par précipitation physico-chimiques. Ainsi, la demande en oxygène sera réduite car il reste peu de DCO à dégrader et la croissance cellulaire limitée car les populations seraient essentiellement autotrophes. Ce travail de thèse a donc été centré sur les points suivants : (i) les performances d'un bioréacteur à membrane fonctionnant sous une charge essentiellement azotée, ces performances sont analysées en termes de réactions d'élimination des fractions polluantes et de filtrabilité des suspensions, (ii) suivi et modélisation des cinétiques de réactions, (iii) définition d'outils simples de dimensionnement. Des méthodologies expérimentales originales ont été mises en place, réacteur pilote et méthodes d'analyses spécifiques (suivi en ligne des composés azotés, méthodes respirométriques notamment). Les résultats obtenus ont permis d'évaluer (i) les capacités de nitrification en régime permanent, (ii) les grandeurs cinétiques propres aux populations autotrophes suivant le modèle ASM1 (XBA, YA, KSH, bA), (iii) la filtrabilité des suspensions sur membranes poreuses avec une contribution significative de la résistance hydraulique due à un biofilm qui se développe en surface de membrane (par rapport aux autres processus, notamment les phénomènes d'adsorption ou bouchage de pores). Ces résultats ont permis de définir des nouveaux outils simples d'extrapolation, notamment des grandeurs réactionnelles spécifiques propres aux espèces nitrifiantes comme le ratio rSNHmax/OURendaut exprimant un rapport de vitesse de nitrification par une grandeur proportionnelle à la concentration en biomasse nitrifiante. / Membrane bioréactor, coupling bioreactions and porous membrane separation in a same unit, allows working with high biomass concentrations what improves bioreaction rates but penalizes the separation step. This work had as objective to study the nitrifiers micro-organisms on the membrane fouling dynamic and on the nitrogen removal efficiency. According to precedent works of the laboratory and the analyses of references, the objective was axed on the modeling tools available for heterotrophe and autotrophe biomass caracterisation. Then, specific methodologies were carried out, lab scale pilots and analytical methods, notably for active biomass observations and identification. Theses tools underline the role of these dominant populations (i) the use of ASM to simulate the biomass performances in relation with working conditions and (ii) the respirometric methods to experimentally quantify the specific biomass activity. Then results clearly pointed out the role of the COD/N ratio on the biomass and MBR performances. Passing from the urban wastewater to synthetic substrate with a final COD/N ratio of 1.5, the proportion of autotrophic bacteria in active biomass increased from 16 to 72%. Specific criteria were defined to characterise the biomass activity as rnitrif/ OURAutoend or rDCO / OURHetend allowing universal parameters definition