A indústria têxtil é caracterizada por seu grande consumo de água e descarte de efluentes. Nesse trabalho foram mapeadas as oportunidades de reúso de água dentro da indústria têxtil de estudo. A partir desse mapeamento e dos requisitos de cada uso, foi proposto o reúso de água para lavagem de pisos e equipamentos; irrigação de jardim; preparo de banhos de tingimento e banho químico; preparo de goma; uso nas caixas de lavagem do processo de tingimento; torre de resfriamento; e descarga em vasos sanitários. O maior consumo de água ocorre no tingimento dos fios. Atualmente todo efluente gerado por esse processo é encaminhado para a Estação de Tratamento de Águas Residuárias (ETAR) e tratado por flotação por ar dissolvido (FAD). O efluente da ETAR não apresenta características que possibilitem o reúso, para isso foi estudado o uso de filtração sob pressão por membranas. Foram testadas cinco combinações diferentes de membrana envolvendo membranas de microfiltração (MF), ultrafiltração (UF) e nanofiltração (NF). A melhor configuração foi usando membrana de MF (0,05 μm) seguida de membrana de NF (200 Da) . A membrana de NF foi capaz de remover em média 68% de cálcio, 45% de condutividade, 35% da DBO bruta, 40% da DQO bruta, 62% de dureza, 48% de magnésio, 42% dos SDT, 74% de sulfato e 36% de turbidez. No entanto, o permeado não apresentou qualidade adequada para reúso direto nos processos de tigimento da indústria, pois apresentou uma elevada concentração de matéria orgância (DBO bruta 1.266 mg O2.L-1) e sais (condutividade: 8.000 μS cm-1), sendo recomendável estudos adicionais com incorporação de etapa de tratamento biológico anterior à filtração em membranas de osmose reversa, ou até mesmo de nanofiltração com eventual posterior diluição, para se avaliar a possibilidade de reúso direto no processo de tingimento. Por outro lado, a água obtida após a filtração em membrana de MF apresenta qualidade compatível com reúso para lavagens de pisos e equipamentos e descargas em vasos sanitários. / The textile industry is characterized by high consumption of water and the disposal of effluents. In this work, it was mapped the opportunities for water reuse in a tipical textile industry placed in São Carlos City, Brazil. Using the mapping and the requirements of each use, it was proposed the reuse of water to wash floors and equipment; garden irrigation; preparation of dyeing baths and chemical bath; preparation of sizing; use in the washing of the dyeing process; cooling tower; and discharged into toilets. The highest water consumption occurs in dyeing process. Currently all effluent generated by this process is sent to the Wastewater treatment plant (WWTP) of the industry and treated by dissolved air flotation (DAF). The effluent of the WWTP does not have characteristics that make possible the reuse, for this it was studied the use of filtration under pressure by membranes. Five different membrane combinations involving microfiltration (MF), ultrafiltration (UF) and nanofiltration (NF) membranes were tested. The best configuration was using a MF membrane (0.05 μm) followed by NF membrane (200 Da). The NF membrane was able to remove on average 68% of calcium, 45% of conductivity, 35% of crude BOD, 40% of crude COD, 62% of hardness, 48% of magnesium, 42% of SDT, 74% of Sulfate and 36% turbidity, however, the permeate does not have sufficient quality for direct reuse in the dying process, because it presents a high concentration of organic matter (gross BOD 1,266 mg O2.L-1) and salts (conductivity: 8.000 μS cm-1), but it is recommended that additional studies incorporate a biological treatment step prior to filtration in reverse osmosis membranes, or even nanofiltration with eventual dilution, to evaluate the possibility of direct reuse in the dyeing process. On the other hand, the water obtained after MF membrane filtration presents quality compatible with reuse for floor washes and equipment and discharges in toilets.

Une étude a été menée sur la faisabilité technique du traitement de potabilisation des eaux de forage contaminées à l’arsenic par procédé membranaire. Pour ce faire, l’efficacité de deux membranes commerciales (NF270 et TW30) vis-à-vis de la rétention des espèces d’arsenic, arsénite [As (III)] et arséniate [As (V)], a été d’abord comparée sous différentes conditions expérimentales. Ensuite, la contribution des différents mécanismes intervenant dans l’élimination des espèces d’arsenic a été identifiée. Enfin, la membrane la plus performante a été utilisée pour le traitement d’une eau souterraine naturellement riche en arsenic. Il ressort de cette étude que la pression opératoire et le pH sont les paramètres importants sur lesquels il faut agir pour améliorer l’efficacité du système membranaire pour le traitement de l’arsenic. L’As(V) est facilement éliminé par rapport à l’As (III) aussi bien avec la membrane de nanofiltration que d’osmose inverse. Toutefois, la membrane d’osmose inverse (TW30) permet une meilleure élimination des différentes espèces d’arsenic que la membrane NF270. Cela est dû au fait que la membrane TW30 est une membrane dense. L’application de cette membrane pour la production d’eau potable à partir d’une eau de forage contenant 413,74µg/L d’arsenic total dont 405,63µg/L d’As (V) et 8,11 µg/L d’As (III) a donné une concentration d’arsenic total dans l’eau traitée de 9,99 µg/L soit un taux de rétention de 97,6% et un volume d’eau traité correspondant à 70% du volume d’eau brute. Il est donc possible de mettre en place un procédé de traitement de ces eaux de forage à partir de la membrane TW30 afin de produire de l’eau potable pour les populations du nord du Burkina Faso. La performance de ce procédé peut être encore améliorée en oxydant l’As (III) en As (V) avant filtration. / In order to produce potable water for human consumption, a study was carried out on the technical feasibility of arsenic-rich borehole water treatment by membrane process. Firstly the efficiency of two commercial membranes (NF2Une étude a été menée sur la faisabilité technique du traitement de potabilisation des eaux de forage contaminées à l’arsenic par procédé membranaire. Pour ce faire, l’efficacité de deux membranes commerciales (NF270 et TW30) vis-à-vis de la rétention des espèces d’arsenic, arsénite [As (III)] et arséniate [As (V)], a été d’abord comparée sous différentes conditions expérimentales. Ensuite, la contribution des différents mécanismes intervenant dans l’élimination des espèces d’arsenic a été identifiée. Enfin, la membrane la plus performante a été utilisée pour le traitement d’une eau souterraine naturellement riche en arsenic. Il ressort de cette étude que la pression opératoire et le pH sont les paramètres importants sur lesquels il faut agir pour améliorer l’efficacité du système membranaire pour le traitement de l’arsenic. L’As(V) est facilement éliminé par rapport à l’As (III) aussi bien avec la membrane de nanofiltration que d’osmose inverse. Toutefois, la membrane d’osmose inverse (TW30) permet une meilleure élimination des différentes espèces d’arsenic que la membrane NF270. Cela est dû au fait que la membrane TW30 est une membrane dense. L’application de cette membrane pour la production d’eau potable à partir d’une eau de forage contenant 413,74µg/L d’arsenic total dont 405,63µg/L d’As (V) et 8,11 µg/L d’As (III) a donné une concentration d’arsenic total dans l’eau traitée de 9,99 µg/L soit un taux de rétention de 97,6% et un volume d’eau traité correspondant à 70% du volume d’eau brute. Il est donc possible de mettre en place un procédé de traitement de ces eaux de forage à partir de la membrane TW30 afin de produire de l’eau potable pour les populations du nord du Burkina Faso. La performance de ce procédé peut être encore améliorée en oxydant l’As (III) en As (V) avant filtration.70 and TW30) for different arsenic species removal, arsenite [As (III)] and arsenate [As (V)], was compared under various experimental conditions. Afterward, the contribution of mechanisms in As species removal was determined. Finally, the most efficient membrane was used for As-rich groundwater treatment. Results show that, applied pressure and feed pH are the important parameters which must be considered if As removal wants to be improved. As (V) is much easily removed than As (III) both NF270 and TW30 membranes. Nevertheless, TW30 membrane has a better removal of As species than NF270 membrane. It is due to the fact that TW30 membrane is a compact membrane. The application of this membrane for potable water production from naturally contaminated groundwater containing 413.74 µg/L of total arsenic (405.63 µg/L of As (V) and 8.11 µg/L of As (III)) gave a treated water of 9.99 µg/L (97.6% of rejection) of total As concentration and water produced volume equivalent to 70% of raw water volume. Therefore, it is possible to implement a treatment process with TW30 membrane to remove arsenic from naturally contaminated groundwater coming from the northern part of Burkina Faso. The efficiency of this process can be improved again by oxidizing As (III) in As (V) before filtration.

O objetivo deste trabalho foi estudar a remoção de metais pesados de efluentes sintéticos aquosos através de nanofiltração, com utilização de membrana de poliamida. A membrana utilizada constituída de poliamida apresentou uma boa permeabilidade hidráulica, constatada pela linearidade de fluxo com a variação de pressão de trabalho. Os metais estudados foram cobre, cádmio, zinco, chumbo e níquel com especiação de nitrato e sulfato. O desempenho do sistema foi verificado pela variação dos parâmetros operacionais (pressão e fluxo), associados também com a variação da salinidade e da concentração do metal. Em uma etapa inicial estudou-se a remoção de metais (nitrato e sulfato) isoladamente em uma mesma concentração molar, na pressão de 10 bar, comparando-se as rejeições com e sem agente complexante (EDTA). Em uma segunda etapa, estudou-se o desempenho da membrana, com misturas dos metais (nitrato) e mistura de metais (sulfato), também com e sem agente complexante, os resultados mostraram que a presença de agente complexante melhorou a rejeição dos metais. Nestas misturas estudaram-se os efeitos das concentrações (0,001; 0,0005 e 0,0001mol/L) e das pressões (5; 7; 10 e 12,5 bar) no sistema de remoção, constatou-se que o aumento da concentração e diminuição da pressão afeta a remoção. Em uma terceira etapa, estudou-se a influência da salinidade pela mistura de dois metais de mesma especiação (sulfato), comparando a remoção na pressão de 10 bar. Os resultados atestaram uma rejeição maior que 94 % para todos metais, na pressão de 10 bar, indicando um excelente desempenho e fluxo adequado, daí viabilidade de processo para todas as concentrações testadas. A pertinência do teste se justifica pela adequação do permeado ao atendimento aos padrões ambientais de concentração de metais e confirmam a eficácia do sistema de nanofiltração na remoção de metais pesados / The objective of this work was to study the removal of heavy metals of aqueous synthetic efluentes through nanofiltração, with use of polyamide membrane. The membrane used constituted of polyamide it presented a good hydraulic permeabilidade, verified by the flow linearidade with the variation of work pressure. The studied metals were copper, cadmium, zinc, lead and nickel with speciation of nitrate and sulfate. The performance of the system was verified by the variation of the operational parameters (pressure and flow), also associated with the variation of the salinity and of the concentration of the metal. In an initial stage it was studied the removal of metals (nitrate and sulfate) separately in a same concentration molar, in the pressure of 10 bar, being compared the rejections with and without agent complexante (EDTA). In a second stage, it was studied the performance of the membrane, with mixtures of the metals (nitrate) and mixture of metals (sulfate), also with and without agent complexante, the results showed that the presence of agent complexante improved the rejection of the metals. In these mixtures they were studied the effects of the concentrations (0,001; 0,0005 and 0,0001mol/L) and of the pressures (5; 7; 10 and 12,5 bar) in the removal system, it was verified that the increase of the concentration and decrease of the pressure affects the removal. In a third stage, it was studied the influence of the salinity by the mixture of two metals of same speciation (sulfate), comparing the removal in the pressure of 10 bar. The results attested a larger rejection than 94% for all metals, in the pressure of 10 bar, indicating an excellent acting and appropriate flow, then process viability for all of the tested concentrations. The importance of the test is justified for the adaptation of the permeated to the service to the environmental patterns of concentration of metals and they confirm the effectiveness of the nanofiltração system in the removal of heavy metals

A indústria têxtil é caracterizada por seu grande consumo de água e descarte de efluentes. Nesse trabalho foram mapeadas as oportunidades de reúso de água dentro da indústria têxtil de estudo. A partir desse mapeamento e dos requisitos de cada uso, foi proposto o reúso de água para lavagem de pisos e equipamentos; irrigação de jardim; preparo de banhos de tingimento e banho químico; preparo de goma; uso nas caixas de lavagem do processo de tingimento; torre de resfriamento; e descarga em vasos sanitários. O maior consumo de água ocorre no tingimento dos fios. Atualmente todo efluente gerado por esse processo é encaminhado para a Estação de Tratamento de Águas Residuárias (ETAR) e tratado por flotação por ar dissolvido (FAD). O efluente da ETAR não apresenta características que possibilitem o reúso, para isso foi estudado o uso de filtração sob pressão por membranas. Foram testadas cinco combinações diferentes de membrana envolvendo membranas de microfiltração (MF), ultrafiltração (UF) e nanofiltração (NF). A melhor configuração foi usando membrana de MF (0,05 μm) seguida de membrana de NF (200 Da) . A membrana de NF foi capaz de remover em média 68% de cálcio, 45% de condutividade, 35% da DBO bruta, 40% da DQO bruta, 62% de dureza, 48% de magnésio, 42% dos SDT, 74% de sulfato e 36% de turbidez. No entanto, o permeado não apresentou qualidade adequada para reúso direto nos processos de tigimento da indústria, pois apresentou uma elevada concentração de matéria orgância (DBO bruta 1.266 mg O2.L-1) e sais (condutividade: 8.000 μS cm-1), sendo recomendável estudos adicionais com incorporação de etapa de tratamento biológico anterior à filtração em membranas de osmose reversa, ou até mesmo de nanofiltração com eventual posterior diluição, para se avaliar a possibilidade de reúso direto no processo de tingimento. Por outro lado, a água obtida após a filtração em membrana de MF apresenta qualidade compatível com reúso para lavagens de pisos e equipamentos e descargas em vasos sanitários. / The textile industry is characterized by high consumption of water and the disposal of effluents. In this work, it was mapped the opportunities for water reuse in a tipical textile industry placed in São Carlos City, Brazil. Using the mapping and the requirements of each use, it was proposed the reuse of water to wash floors and equipment; garden irrigation; preparation of dyeing baths and chemical bath; preparation of sizing; use in the washing of the dyeing process; cooling tower; and discharged into toilets. The highest water consumption occurs in dyeing process. Currently all effluent generated by this process is sent to the Wastewater treatment plant (WWTP) of the industry and treated by dissolved air flotation (DAF). The effluent of the WWTP does not have characteristics that make possible the reuse, for this it was studied the use of filtration under pressure by membranes. Five different membrane combinations involving microfiltration (MF), ultrafiltration (UF) and nanofiltration (NF) membranes were tested. The best configuration was using a MF membrane (0.05 μm) followed by NF membrane (200 Da). The NF membrane was able to remove on average 68% of calcium, 45% of conductivity, 35% of crude BOD, 40% of crude COD, 62% of hardness, 48% of magnesium, 42% of SDT, 74% of Sulfate and 36% turbidity, however, the permeate does not have sufficient quality for direct reuse in the dying process, because it presents a high concentration of organic matter (gross BOD 1,266 mg O2.L-1) and salts (conductivity: 8.000 μS cm-1), but it is recommended that additional studies incorporate a biological treatment step prior to filtration in reverse osmosis membranes, or even nanofiltration with eventual dilution, to evaluate the possibility of direct reuse in the dyeing process. On the other hand, the water obtained after MF membrane filtration presents quality compatible with reuse for floor washes and equipment and discharges in toilets.

Future nanofiltration (NF) membranes used for selective separations of ions and small organic molecules must maintain performance in environments where high concentrations of total dissolved solvents or foulants are present. These challenges can be addressed through the development of composite membranes, as well as the engineering of enhanced surface properties and operating conditions for existing commercial membranes. In this work, ion transport through commercial thin film composite (TFC) polyamide NF membranes were studied in both lab-prepared salt solutions and industrial wastewater. The dependence of several variables on ion rejection was investigated, including ion radius, ion charge, ionic strength, and temperature. The impact of scaling and increasing ionic concentration on membrane performance during recovery of industrial wastewater was investigated. Fouling of the membrane surface was reduced by enhancing commercial NF membrane surfaces via aqueous-phase esterification of lignin sulfonate. NF membranes were also created utilizing an ionic liquid solvent (1-ethyl-3-methylimidazolium acetate) to integrate composite materials into cellulose. Composite materials such as graphene oxide quantum dots, iron III particles, and lignin have been shown to be interact strongly with cellulose in solution with ionic liquid and bind together cellulose chains via hydrogen bonds following nonsolvent induced phase inversion. Studies suggest the composite materials modify membrane surface chemistry and improve selectivity of small organic molecules (~300 nm) while allowing for the complete passage of ions.

This dissertation investigates the importance of diffusional and convective fluxes for salts in reverse osmosis (RO) and nanofiltration (NF) membranes. Moreover, the physical and thermodynamic factors controlling the salt permeability are analyzed. The study utilizes direct osmosis (DO) experiments and RO experiments, the later using both flat sheet and spiral wound membrane configurations. The salts considered are chlorides and acetates of alkali metals and alkaline earth metals. The equation governing the salt transport in DO experiments is derived and a phenomenon inverse to concentration polarization in RO is observed. The salt permeability in DO is equal to the salt permeability calculated for the valid cases of the used RO models. DO is suggested as an alternative method in characterizing the salt transport in membranes. The method can be more advantageous than RO due to the lower costs and simplicity of the apparatus. The models used to calculate the salt transport parameters in RO experiments are Spiegler-Kedem model, which considers both diffusion and convection of salt, and Kimura-Sourirajan model, which considers only diffusion of salt. It is found that diffusion is the dominant mechanism of transport in both RO and NF membranes. The percentage of the salt diffusional flux of the total flux is highest for seawater membranes and it is approximately equal for brackish water and nanofiltration membranes. The salt diffusive flux contribute more to the total flux for the 1:2 salts than for 1:1 salts. The two RO models are found equivalent in determining the salt permeability for only the seawater membranes. The Kimura-Sourirajan model overestimates the salt permeability coefficient for salts with rejection coefficient lower than 86%. The permeation rates for studied salts follow the lyotropic series regardless the membrane type (RO or NF), the membrane configuration (flat sheet or spiral wound), the process (DO or RO), or the models used for the calculations. This order of salt permeability is explained by the hydration of the cations, which is quantified by the enthalpy and entropy of hydration. The relative free energy theory can also be used to predict the salt permeability in a membrane based on preliminary data.

This study aimed to obtain 15% total solids and reduced mineral content in milk UF permeate by nanofiltration, hydrolysing the lactose content of nano-concentrate enzymically, partially substituting sucrose in ice cream formulations with hydrolysed lactose nano-concentrate (HLNC), and investigating the effects of HLNC on the physio-chemical and sensory characteristics of ice cream. The desired 15% total solids in the nano-concentrate was achieved after three fold concentration of milk UF permeate. The colour of milk permeate changed, pH and mineral content decreased, and crude protein content, lactose content and titratable acidity increased. The lactose content was hydrolysed by enzyme lactase. HLNC was used to replace 25% and 50% of sucrose in ice cream formulations. Springiness, cohesiveness, chewiness, adhesiveness, hardness, iciness, Ph and colour were not significantly affected. Viscosity, freezing point, glass transition temperature, melting temperature, gumminess and sweetness were significantly decreased, whereas freezing time, saltiness and cooked flavour were significantly increased. The overall acceptability of ice cream significantly decreased at 50% but was insignificantly affected at the 25% level. These results indicate that about one quarter of sucrose could be replaced by HLNC. / Master of Science (Hons) (Food Technology)

In the Australian wine industry, cold stabilisation is a widely used industrial process to prevent tartrate instability in bottled wines. This process involves cooling the wine close to its freezing point for extended periods, thereby inducing tartrate precipitation. However, it has several important disadvantages. Consequently, alternative methods to cold stabilisation have been developed. This includes electrodialysis, nanofiltration and contact processes. In this study, current knowledge regarding performance and cost of cold stabilisation and alternative technologies for tartrate stabilisation is reviewed. Whilst there have been occasional cost comparisons between cold stabilisation and alternative technologies, existing data is not suitable for properly evaluating the relative economics of the different process options. Therefore, alternative technologies to cold stabilisation, including the Westfalia process, nanofiltration and electrodialysis were compared for both technical and economic performance. Berri Estates Winery was used as the basis for engineering calculations and conceptual cost estimates. This is the first time that such a comprehensive evaluation has been undertaken of a broad range of alternative technologies for tartrate stabilisation during wine production. Product loss was a key cost driver in differentiating tartrate stabilisation processes. Cold stabilisation was found to be the most economic treatment process irrespective of scale or winery size. The Westfalia process and nanofiltration were the next most cost effective options. Data for economic evaluation and environmental assessment were summarised in a survey form that was circulated to technical experts from Hardy Wine Company, the Australian Wine Research Institute (AWRI) and the University of Adelaide. The purpose of the survey was to obtain the experts’ opinions on the merits of the alternative technologies. The results of this survey were used for comparison between current cold stabilisation and alternative technologies, by performing multi-criteria decision analysis (MCDA). This represents an original application of MCDA techniques to decision making in the wine industry. The MCDA analysis identified a strong preference by experts for nanofiltration combined with centrifugation as an alternative to cold stabilisation. As a consequence, laboratory investigations and field testing of nanofiltration were conducted to obtain new and practical information which was not presently available and relevant to understanding and implementing this process for tartrate stabilisation of wine. The laboratory experiments were performed with a range of membranes and tartrate unstable wines (i.e. Semillon, Colombard and Shiraz) using a purpose-designed laboratory-scale continuously-stirred batch-test membrane cell. The results showed that a range of commercial nanofiltration membranes with a nominal molecular weight cut-off (MWCO) between 200 and 500 Daltons (Da) were able to achieve tartrate stabilisation of all wines tested. This was achieved at moderate pressures less than 20 bar with a recovery of at least 50 %. It was also observed that seeding of wine following nanofiltration might reduce the holding time required to achieve stability and also enable reductions in the recovery rate to values of less than 50 %. The field testing was performed at Berri Estates Winery in the Riverland region of South Australia. The testing was performed using an existing commercial membrane system. This membrane system was already used for juice/wine concentration. The nanofiltration membranes had a nominal MWCO of 300 Da. The testing was conducted on Colombard and Shiraz wines. The field tests confirmed that nanofiltration could successfully tartrate stabilise Colombard and Shiraz wines at recoveries of 50 %; without seeding; within relatively short holding periods of less than four hours; and at flux rates between 5 and 10 L/m²/h. Crystallisation kinetics were also studied. At low recovery, the crystallisation was initially controlled by diffusion step, then surface integration. However, at high recovery, the crystallisation was controlled solely by surface integration. Sensory testing (by duo-trio difference tests) produced adverse sensory outcomes when compared with treatment of the same wines by cold stabilisation. Unfortunately, it could not be established whether this problem was inherent to the process or arose from unrelated factors. Setting aside the adverse sensory result, this is the first time that technical feasibility of nanofiltration for tartrate stabilisation has been successfully demonstrated. Further field testing and sensory evaluation of nano-filtered wines should be carried out to verify the effect of nanofiltration on wines. If the process is successful and favourable, the process design for implementation of a production scale nanofiltration for tartrate stabilisation should then be optimised. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1292872 / Thesis (Ph.D.) -- University of Adelaide, School of Chemical Engineering, 2007.

In the Australian wine industry, cold stabilisation is a widely used industrial process to prevent tartrate instability in bottled wines. This process involves cooling the wine close to its freezing point for extended periods, thereby inducing tartrate precipitation. However, it has several important disadvantages. Consequently, alternative methods to cold stabilisation have been developed. This includes electrodialysis, nanofiltration and contact processes. In this study, current knowledge regarding performance and cost of cold stabilisation and alternative technologies for tartrate stabilisation is reviewed. Whilst there have been occasional cost comparisons between cold stabilisation and alternative technologies, existing data is not suitable for properly evaluating the relative economics of the different process options. Therefore, alternative technologies to cold stabilisation, including the Westfalia process, nanofiltration and electrodialysis were compared for both technical and economic performance. Berri Estates Winery was used as the basis for engineering calculations and conceptual cost estimates. This is the first time that such a comprehensive evaluation has been undertaken of a broad range of alternative technologies for tartrate stabilisation during wine production. Product loss was a key cost driver in differentiating tartrate stabilisation processes. Cold stabilisation was found to be the most economic treatment process irrespective of scale or winery size. The Westfalia process and nanofiltration were the next most cost effective options. Data for economic evaluation and environmental assessment were summarised in a survey form that was circulated to technical experts from Hardy Wine Company, the Australian Wine Research Institute (AWRI) and the University of Adelaide. The purpose of the survey was to obtain the experts’ opinions on the merits of the alternative technologies. The results of this survey were used for comparison between current cold stabilisation and alternative technologies, by performing multi-criteria decision analysis (MCDA). This represents an original application of MCDA techniques to decision making in the wine industry. The MCDA analysis identified a strong preference by experts for nanofiltration combined with centrifugation as an alternative to cold stabilisation. As a consequence, laboratory investigations and field testing of nanofiltration were conducted to obtain new and practical information which was not presently available and relevant to understanding and implementing this process for tartrate stabilisation of wine. The laboratory experiments were performed with a range of membranes and tartrate unstable wines (i.e. Semillon, Colombard and Shiraz) using a purpose-designed laboratory-scale continuously-stirred batch-test membrane cell. The results showed that a range of commercial nanofiltration membranes with a nominal molecular weight cut-off (MWCO) between 200 and 500 Daltons (Da) were able to achieve tartrate stabilisation of all wines tested. This was achieved at moderate pressures less than 20 bar with a recovery of at least 50 %. It was also observed that seeding of wine following nanofiltration might reduce the holding time required to achieve stability and also enable reductions in the recovery rate to values of less than 50 %. The field testing was performed at Berri Estates Winery in the Riverland region of South Australia. The testing was performed using an existing commercial membrane system. This membrane system was already used for juice/wine concentration. The nanofiltration membranes had a nominal MWCO of 300 Da. The testing was conducted on Colombard and Shiraz wines. The field tests confirmed that nanofiltration could successfully tartrate stabilise Colombard and Shiraz wines at recoveries of 50 %; without seeding; within relatively short holding periods of less than four hours; and at flux rates between 5 and 10 L/m²/h. Crystallisation kinetics were also studied. At low recovery, the crystallisation was initially controlled by diffusion step, then surface integration. However, at high recovery, the crystallisation was controlled solely by surface integration. Sensory testing (by duo-trio difference tests) produced adverse sensory outcomes when compared with treatment of the same wines by cold stabilisation. Unfortunately, it could not be established whether this problem was inherent to the process or arose from unrelated factors. Setting aside the adverse sensory result, this is the first time that technical feasibility of nanofiltration for tartrate stabilisation has been successfully demonstrated. Further field testing and sensory evaluation of nano-filtered wines should be carried out to verify the effect of nanofiltration on wines. If the process is successful and favourable, the process design for implementation of a production scale nanofiltration for tartrate stabilisation should then be optimised. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1292872 / Thesis (Ph.D.) -- University of Adelaide, School of Chemical Engineering, 2007.

Une voie possible pour la valorisation des liquéfiats de biomasse lignocellulosique comme carburants pourrait être l'hydrotraitement en mélange avec des coupes pétrolières. L'étude des réactions d'hydrodéoxygénation et d'hydrodésulfuration est alors essentielle.<br /><br />Tout d'abord, le travail de thèse a consisté à hydrotraiter un gazole additivé avec différents composés oxygénés modèles. L'influence de l'eau, du CO et du CO2 a aussi été étudiée ce qui a permis de distinguer l'impact des composés oxygénés de celui de leurs produits de réaction.<br /><br />Par la suite, une approche complémentaire a aussi été proposée en utilisant cette fois-ci les fractions d'une huile de pyrolyse mélangées avec le gazole. La mise au point d'une méthode de fractionnement par nanofiltration a été nécessaire et a permis, entre autres, de caractériser de manière plus détaillée cette huile. L'hydrotraitement d'un gazole additivé avec une des fractions obtenues a finalement permis de valider les résultats de la première approche.