The main objective of this investigation is to determine the effect of different physical and chemical parameters on the performance of biofilters, treating hydrophobic organic compounds. pinene was used as a model substance. Alpha-pinene is commonly found in wood, and therefore found at wood storage facilities and wood processing industries [1]. In this experiment two biofilter which were in equal size, were used. Both of them were filled with perlite for treating the alpha pinene contaminated air. One of the columns contained perlite partially coated with silicone oil to make the surface of perlite more hydrophobic. The filters were run at 5, 2.5 and 1.5 l min-1 air flow rate. The results showed that the silicone oil amended filter performed better at 2.5 l/min with a maximum removal rate of 20 g / (m3 h) in comparison with 15 g/ (m3 h) for the filter without oil. The efficiency was approximately the same for both filters at 1.5 and 5 l/min (40 compare to 35 g/m3 bed h). The flow rate was then set to 2.5 l/min once more. The results showed that the removal rate had increased to approximately 35 g/ (m3 h) and that the efficiency of both filters was approximately the same. The difference in results between the initial run and the later at 2.5 l/min is probably depending on that the microorganisms had become adapted to the α-pinene and that the microorganism communities developed differently in the two filters. / Syftet med denna studie var att undersöka om en ökning av biofilterytans hydrofobicitet kan förbättra effektiviteten med avseende på nedbrytning av en hydrofob förening såsom -pinen. En hydrofob yta skulle kunna medföra en ökning i adsorption av hydrofoba föroreningar vilket i sin tur skulle kunna öka tillgängligheten hos föroreningarna för mikroorganismerna. Försöken utfördes med hjälp av två biofilter fyllda med perlit. Ett filter fylldes med obehandlad perlit medan det andra filtret fylldes med perlit som blandats med silikonlja. Båda filtren ympades med mikroorganismer som växt på träflis. Dessa mikroorganismer är anpassade för att bryta ner -pinen då denna förening friges i stora mängder från trä. Resultaten visar att filtret innehållande perlit täckt med silikonolja var mer effektivt med avseende på nedbrytning avpinen under den första tiden av studien (de första 30 dagarna). Skillnaden i effektivitet mellan filtren minskade dock betydligt med tiden så att skillnaden inte var signifikant under resten av studien. Prover från vätskefasen från de båda filtren undersöktes i mikroskop. Dessa studier visade att olika mikroorganismer dominerade i de båda filtren. Filtret innehållande oljetäckt perlit dominerades av stavformiga bakterier medan filtret innehållande obehandlad perlit dominerades av kocker. Båda filtren innehöll en blandkultur av kocker och stavar. Dessutom växte svamp i båda filtren. Dessa resultat visar att en förändring av ytans hydrofobicitet inte bara kan leda till en ökad adsorption av förorening utan den kan också leda till att andra mikroorganismer får en dominerande roll i filtret. Den maximala nedbrytningshastigheten låg mellan 35 och 40 g pinen/(m3h) under hela studien förutom de 30 första dagarna oberoende av luftflödeshastighet (1,5 , 2,5 respektive 5 l/min). Den maximala nedbrytningshastigheten under inledningen av försöket var 15 g/(m3 h) för filtret innehållande obehandlad perlit och 20 g/(m3h) för filtret innehållande oljetäckt perlit. Luftflödet var 2,5 l/min under den inledande perioden. Ökningen i nedbrytningshastighet med tiden indikerar att mikroorganismerna anpassade sig till miljön. Den relativt konstanta nedbrytningshastigheten under resten av studien indikerar att det var de biokemiska reaktionerna som var hastighetsbegränsande och att masstransporten inte hade någon dominerande roll med avseende på att begränsa hastigheten.

In order to evaluate the effect of seaweeds in bio-filtration for removing nitrogen from marine aquaculture and in bioenergy production, Ulva sp. was used in this study. Experiments were triplicated and run in 3-day incubation at salinities with 30 psu, 10 psu and 5 psu in different initial ammonium nitrogen concentrations from 100 μM to 10,000 μM, equivalently to marine aquaculture conditions. The highest concentrations of ammonium removed were about 690 μmol (12.42 mg) NH4+ at 30 psu, 410 μmol (7.38 mg) NH4+ at 10 psu and 350 μmol NH4+(6.3 mg NH4+) at 5 psu in three days of incubation, while highest growth rates of Ulva sp. were 49% and 150% per day at 500 μM of initial ammonium concentration, similarly to the growth rate reported in microalgae. Moreover, after these experiments, biomass of Ulva sp. has been tested for bioenergy producing goals, because the carbohydrate concentration of this alga was very high, reaching 60-70% of DW. Thus, Ulva sp. can be cultured to remove nitrogen concentration in eutrophication conditions at aquaculture systems in combination with the purpose of bioenergy production after harvesting. / Để đánh giá hiệu quả của tảo biển trong việc lọc sinh học loại bỏ hợp chất ni tơ từ việc nuôi trồng thủy sản và trong việc sản xuất năng lượng sinh học, Ulva sp. đã được sử dụng trong nghiên cứu này. Các thí nghiệm được lặp lại 3 lần và chạy trong 3 ngày trong tủ ổn nhiệt tại các điều kiện độ mặn 30psu, 10psu, 5psu ở các nồng độ NH4+-N từ 100μM đến 10.000μM, tương đương với điều kiện nuôi trồng thủy sản nước mặn. Nồng độ cao nhất của NH4+-N được loại bỏ khoảng 690 μmol NH4+(12,42mg NH4 +) tại 30psu, 410μmol NH4+(7,38mg NH4+) tại 10psu và 350 μmol NH4+(6.3mg NH4+) tại 5psu, trong đó tỉ lệ sinh trưởng của Ulva sp. là rất cao, sinh trưởng từ 49 đến 150% mỗi ngày tại nồng độ ammonium ban đầu 500 μM tương đương với sinh trưởng của vi tảo. Hơn nữa, sau các thí nghiệm trên, sinh khối của Ulva sp. được thử nghiệm sản xuất năng lượng sinh học vì hàm lượng carbohydrate trong tảo rất cao, chiếm khoảng 60-70% trọng lượng khô của tảo. Như vậy, Ulva sp. có thể được nuôi trồng để loại bỏ hợp chất ni tơ trong điều kiện phú dưỡng của các hệ thống nuôi trồng thủy sản, kết hợp với mục tiêu sản xuất năng lượng sinh học sau thu hoạch.

<p>The main objective of this investigation is to determine the effect of different physical and chemical parameters on the performance of biofilters, treating hydrophobic organic compounds. pinene was used as a model substance. Alpha-pinene is commonly found in wood, and therefore found at wood storage facilities and wood processing industries [1].</p><p>In this experiment two biofilter which were in equal size, were used. Both of them were filled with perlite for treating the alpha pinene contaminated air. One of the columns contained perlite partially coated with silicone oil to make the surface of perlite more hydrophobic. The filters were run at 5, 2.5 and 1.5 l min-1 air flow rate. The results showed that the silicone oil amended filter performed better at 2.5 l/min with a maximum removal rate of 20 g / (m3 h) in comparison with 15 g/ (m3 h) for the filter without oil. The efficiency was approximately the same for both filters at 1.5 and 5 l/min (40 compare to 35 g/m3 bed h). The flow rate was then set to 2.5 l/min once more. The results showed that the removal rate had increased to approximately 35 g/ (m3 h) and that the efficiency of both filters was approximately the same. The difference in results between the initial run and the later at 2.5 l/min is probably depending on that the microorganisms had become adapted to the α-pinene and that the microorganism communities developed differently in the two filters.</p> / <p>Syftet med denna studie var att undersöka om en ökning av biofilterytans hydrofobicitet kan förbättra effektiviteten med avseende på nedbrytning av en hydrofob förening såsom -pinen. En hydrofob yta skulle kunna medföra en ökning i adsorption av hydrofoba föroreningar vilket i sin tur skulle kunna öka tillgängligheten hos föroreningarna för mikroorganismerna. Försöken utfördes med hjälp av två biofilter fyllda med perlit. Ett filter fylldes med obehandlad perlit medan det andra filtret fylldes med perlit som blandats med silikonlja. Båda filtren ympades med mikroorganismer som växt på träflis. Dessa mikroorganismer är anpassade för att bryta ner -pinen då denna förening friges i stora mängder från trä. Resultaten visar att filtret innehållande perlit täckt med silikonolja var mer effektivt med avseende på nedbrytning avpinen under den första tiden av studien (de första 30 dagarna). Skillnaden i effektivitet mellan filtren minskade dock betydligt med tiden så att skillnaden inte var signifikant under resten av studien. Prover från vätskefasen från de båda filtren undersöktes i mikroskop. Dessa studier visade att olika mikroorganismer dominerade i de båda filtren. Filtret innehållande oljetäckt perlit dominerades av stavformiga bakterier medan filtret innehållande obehandlad perlit dominerades av kocker. Båda filtren innehöll en blandkultur av kocker och stavar. Dessutom växte svamp i båda filtren. Dessa resultat visar att en förändring av ytans hydrofobicitet inte bara kan leda till en ökad adsorption av förorening utan den kan också leda till att andra mikroorganismer får en dominerande roll i filtret. Den maximala nedbrytningshastigheten låg mellan 35 och 40 g pinen/(m3h) under hela studien förutom de 30 första dagarna oberoende av luftflödeshastighet (1,5 , 2,5 respektive 5 l/min). Den maximala nedbrytningshastigheten under inledningen av försöket var 15 g/(m3 h) för filtret innehållande obehandlad perlit och 20 g/(m3h) för filtret innehållande oljetäckt perlit. Luftflödet var 2,5 l/min under den inledande perioden. Ökningen i nedbrytningshastighet med tiden indikerar att mikroorganismerna anpassade sig till miljön. Den relativt konstanta nedbrytningshastigheten under resten av studien indikerar att det var de biokemiska reaktionerna som var hastighetsbegränsande och att masstransporten inte hade någon dominerande roll med avseende på att begränsa hastigheten.</p>

Résumé: L'émission de méthane par les activités anthropiques est un problème majeur en relation caractérisé par le changement climatique. Les sites d'enfouissement sanitaire sont responsables de près d'un quart des émissions de méthane au Canada, deuxième gaz à effet de serre après le dioxyde de carbone. Les solutions de récupération du biogaz, issu de la décomposition des déchets déposés dans des sites d'enfouissement, majoritairement composé de méthane et de dioxyde de carbone, existent. La valorisation énergétique par combustion, le brûlage par torchère, se développent dans plusieurs sites. Cependant, les critères de faisabilité technique et de rentabilité économique de ces procédés ne permettent pas de couvrir l'ensemble des sources et des types d'émissions de biogaz. Dans cette configuration de non respect de ces critères, la biofiltration est un procédé d'élimination du biogaz attractif en particulier pour les sites d'enfouissement de petites tailles et ceux «âgés», ainsi qu'en complément des solutions de valorisation énergétique. Les paramètres essentiels de la biofiltration du méthane sont expliqués dans une revue de littérature. De plus, une présentation de la composition complexe du biogaz est réalisée dans cette revue de littérature, permettant l'introduction d'un nouveau paramètre à prendre en considération lors de l'élimination du méthane : la présence de composés à l'état de traces. Ainsi, après l'étude approfondie de trois paramètres sur la biofiltration du méthane, la température, la quantité de solution nutritive et la concentration de dioxyde de carbone, l'étude s'est portée sur l'analyse de deux mélanges binaires avec l'introduction soit d'un composé aromatique, (mélange méthane/toluène), soit d'un composé aromatique halogéné, (mélange méthane/chlorobenzène). Les effets de la charge d'entrée du méthane et de la variation de la concentration des composés traces ont été étudiés. Enfin, la recherche s'est finalement concentrée sur l'influence du toluène sur l'élimination du méthane en effectuant des expériences micro-cinétique et macro-cinétique sur ce mélange spécifique. La présence de ces deux composés traces s'avère .avoir un impact négatif sur l'élimination du méthane, en particulier aux charges d'entrée de méthane testées les plus élevées||Abstract: Anthropic methane emissions are of major concern since it contributes to climate change. Landfills are responsible for about one quarter of methane emissions in Canada, second most important greenhouse gas after carbon dioxide. Energetic valorization is an adapted solution to capture the biogas, produced from the decomposition of organic matter buried in sanitary landfills, and to convert this mixture of methane and carbon dioxide into heat and electricity. Many sites develop the valorization by combustion or by flaring. However, biogas emissions are not entirely treated, as some technical and economical criterion may be encountered. Biofiltration will be more appropriate for old and small landfills, and will be an efficient complementary treatment to the energetic valorization. The most important parameters of biofiltration had been reviewed. Moreover, the complexity of the biogas mixture is presented, which underline a new parameter to take into account in methane elimination: the presence of trace gas compounds. First, three important parameters, the temperature, the amount of nutrient solution and the concentration of carbon dioxide, were studied to be optimized in the configuration of biofiltration of methane alone. Then, two binary mixtures were analyzed, with the introduction of either an aromatic compound for the mixture methane/toluene, or a halogenated aromatic compound for the mixture of methane/chlorobenzene. The effect of the inlet load of methane was studied, in addition to the concentration of trace gas compounds. Finally, the study focused on the influence of toluene on methane biofiltration in regards to the micro-kinetic or macrokinetic parameters. Both toluene and chlorobenzene, the two trace gas compounds evaluated, had a negative impact on methane biofiltration at high inlet loads of methane, while negligible effects were observed at lower methane inlet load.

Membrane filtration is growing in popularity as a viable technology for drinking water treatment to meet high demand and regulatory requirements. While many improvements have been made to the technology in the past decade, fouling continues to be one of the major operational challenges associated with membranes as it increases operating costs and reduces membrane life. Fouling control typically requires some form of pre-treatment. Biofiltration is a ???green??? technique that can minimize chemical usage and waste during water treatment and is a relatively new application as a pre-treatment for membranes. Proteins and polysaccharides (biopolymers) have been found to contribute most to fouling of low pressure polymeric membranes. Biofiltration has recently been demonstrated as an effective pre-treatment method for reducing biopolymer-associated fouling of this type of membrane (Hall?? et al., 2009). Given that the concentration and composition of organic matter in water is variable, there is an opportunity to explore the applicability of this robust technology for different water types. The primary goals of this research were to assess the effectiveness of direct biofiltration in minimizing ultrafiltration polymeric (PVDF) membrane fouling and at the same time evaluate the biofilter development, biofilter performance based on organics removal potential, and the effect of phosphorus addition (as a nutrient) to the biofilter influent. A pilot-scale treatment train was constructed at the Technology Demonstration Facility at the Walkerton Clean Water Centre. It included two parallel dual media (sand/anthracite) biological filters (preceded by roughing filters), followed by an ultrafiltration membrane unit. Experiments were conducted using water from the Saugeen River (Ontario, Canada) whose primary form of carbon is humic material. The biofilters were allowed to acclimate and biofilter performance and organics removal were tested over a fourteen month period, the last four months of which were dedicated to phosphorus enhancement experiments. The membrane fouling experiments started seven months following the start-up of the biofilters, after confirmation of steady-state operation. Biofilter water samples were analyzed for natural organic matter constituents along with other water quality parameters, and biomass quantity and activity in the media were measured. Biomass activity in the biofilter media and biopolymer removal through the biofilter indicated a rapid acclimation period, and also demonstrated similar performance of the parallel biofilters during start-up and steady-state operation. The biofilters achieved 21% removal of the biopolymers on average following acclimation, while reduction of the humic fractions was not observed. A linear relationship between biopolymer removal and its concentration in the river water was observed (first-order process). Membrane fouling experiments were conducted using both untreated and biofiltered river water. The fouling rates were computed by monitoring changes in transmembrane pressure over time. Analysis of the samples with liquid chromatography-organic carbon detection confirmed the significant contribution of biopolymers to irreversible and reversible membrane fouling rates even when only present at low concentrations. During the phosphorus enhancement phase, two different phosphorus doses were fed into the influent of one of the parallel biofilters in order to achieve a target C:N:P ratio of roughly 100:10:1. Although initially (first month of the dosing period) an increase in the removal of dissolved organic carbon and ultraviolet-absorbance was observed in the phosphorus-enhanced biofilter, this was not sustained. Phosphorus addition did not affect biopolymer removal or biomass quantity and activity in the biofilter, and the membrane fouling experiments during this period did not show any significant effect of phosphorus addition.

Orientador: Denise Bevilaqua / Orientador: Oswaldo Garcia Júnior (in memorian) / Banca: Luis Gonzaga Santos Sobral / Banca: Domingo Cantero Moreno / Resumo: Neste trabalho foram realizados ensaios para o estudo da viabilidade da conversão de lavadores químicos (tecnologia química muito utilizada para a remoção de H2S) em biofiltros percoladores para a remoção de H2S. Foi investigado o efeito inibitório da concentração de sulfato no meio de recirculação de nutrientes, o efeito do pH, da vazão de recirculação de nutrientes, da concentração de alimentação de H2S na corrente gasosa e do tempo de residência na eficiência de remoção de H2S em dois biofiltros percoladores, um recheado com espuma de poro aberto de poliuretano e o outro com anéis de Pall de polipropileno. Durante a etapa de imobilização dos micro-organismos foi observado, experimentalmente, que o anel de Pall de polipropileno não é um bom suporte para a imobilização de Thiobacillus denitrificans e, portanto, no caso da conversão de um lavador químico constituído por um leito de recheio de anéis de Pall em um biofiltro percolador, seria apropriada a substituição deste suporte por espuma de poro aberto de poliuretano, por exemplo, que demonstrou ser um bom suporte para a formação do biofilme. Durante o estudo do efeito do pH observou-se que o aumento de pH aumenta a porcentagem de remoção de H2S, sendo que nas condições utilizadas, o intervalo de pH ótimo ficou entre 7,6 - 8,5. O efeito inibitório da concentração de sulfato foi observado a partir de 16,5 g L-1 no biofiltro de espuma de poro aberto de poliuretano e de 13,0 g L-1 no biofiltro de anéis de Pall de polipropileno. Os efeitos da vazão de recirculação de nutrientes e do tempo de residência do gás foram mais evidentes no biofitro de anéis de Pall comparado a espuma de poro aberto, devido, provavelmente, às características do suporte. No biofiltro de espuma de poro aberto, a diminuição do tempo de residência afetou a... (Resumo completo, clicar acesso eletrônico baixo) / Abstract: In this work experiments were carried out in order to study the viability of conversion of chemical scrubbers (current technology) to biotrickling filter for removing H2S. Many parameters were investigated, such as, the inhibitory effect of sulfate concentration in the nutrient recirculation, the effect of the pH, the flow rate of recirculating nutrient, the inlet H2S concentration and the gas stream residence time in the H2S removal capacity in two biotrickling filter. One of them was packaged with open pore polyurethane foam and other with polypropylene Pall rings. During and after the immobilization stage it was observed, experimentally, that polypropylene Pall rings is not a good support for immobilizing Thiobacillus denitrificans. Thus, in the case of a chemical packaged scrubber conversion using such support in a biotrickling filter, it would be appropriate to replace it by open pore polyurethane foam, for instance, which demonstrated to be a better support to the biofilm to establish. It was shown that increasing the pH an increase in the H2S removal was detected. In this experimental work conditions, the optimum pH range was from 7.6 to 8.5. The inhibitory effect of the sulfate concentration was observed from 16.5 g L-1 in the open pore polyurethane foam biofilter and 13.0 g L-1 in the polypropylene Pall rings biofilter. The effects of the flow rate of the recirculating nutrient and the gas residence time were more evident in the Pall ring biofilter when compared with the open pore foam, probably due to the support characteristics. In the open pore foam biofilter, decreasing the residence time the H2S removal percentage was affected only for less than 9 s, whereas in the Pall rings biofilter, before 33 s. In both biofilters as lower the residence time, lower the H2S removal percentage. In the open pore polyurethane foam... (Complete abstract click electronic access below) / Mestre

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La présente étude visait à établir la capacité d’enlèvement de l’azote des effluents domestiques par le procédé à culture fixée immergée BIO-FOSSEMD, conçu pour les petites localités. Des essais ont été effectués avec une unité pilote comprenant un réacteur de 15 litres. Aéré en continu et soumis à des charges de 35 g N-NH4+ m-2 d-1 et 323 g DBO5 m-2 d-1, ce procédé a atteint 96% de nitrification, atteignant régulièrement des valeurs inférieures à 2 mg N-NH4+/L. Sous aération intermittente du réacteur, l’efficacité de l’enlèvement de NH4+ et de NO3- dépend de la durée des périodes aérobie et anoxie. Avec un cycle de 24 h comptant 75% d’aération, les concentrations en azote à l’effluent ont varié de 0,4 à 7,4 mg N-NH4+ /L et de 10 à 21 mg N-NO3-/L. Les taux maximaux de nitrification et de dénitrification s’élèvent à 58 g N-NH4+ m-2 d-1 et 52 g N-NO3- m-2 d-1, respectivement. / The present study was conducted to establish the nitrogen removal capacity for a domestic effluent of the submerged fixed-film process BIO-FOSSEMD. This process has been especially designed for small communities and is based on the use of textile as bacterial support. When aerated continuously and subjected to loads of 35 g N-NH4+ m-2 d-1 and 323 g DBO5 m-2 d-1, this process reached 96% of nitrification, while providing 98% biological oxygen demand removal and 91% suspended solids removal. Under these conditions, values lower than 2 mg N-NH4+/L were measured on a regular basis in the effluent. When the reactor is operated under intermittent aeration, NH4+ and NO3- removal efficiencies depend on the duration of aerobic and anoxic periods. With a 24 h cycle, including 75% of aeration, the effluent nitrogen concentrations varied from 0,4 to 7,4 mg N-NH4+/L and from 10 to 21 mg N-NO3-/L. Under continuous aeration, total nitrogen removal average was around 49%, reaching over 70% at some point. Similar nitrogen removal was reached under intermittent aeration. Kinetic tests conducted ex situ gave a maximal nitrification rate of 58 g N-NH4+ m-2 d-1 and a maximal denitrification rate of 52 g N-NO3- m-2 d-1.

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