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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Development and mathematical modelling of affinity system based on novel matrix

Onwuasoanya, Daniel I. January 1987 (has links)
No description available.
2

Protein Recovery from Secondary Paper Sludge and Its Potential Use as Wood Adhesive

Pervaiz, Muhammad 19 December 2012 (has links)
Secondary sludge is an essential part of biosolids produced through the waste treatment plant of paper mills. Globally paper mills generate around 3.0 million ton of biosolids and in the absence of beneficial applications, the handling and disposal of this residual biomass poses a serious environmental and economic proposition. Secondary paper sludges were investigated in this work for recovery of proteins and their use as wood adhesive. After identifying extracellular polymeric substances as adhesion pre-cursors through analytical techniques, studies were carried out to optimize protein recovery from SS and its comprehensive characterization. A modified physicochemical protocol was developed to recover protein from secondary sludge in substantial quantities. The combined effect of French press and sonication techniques followed by alkali treatment resulted in significant improvement of 44% in the yield of solubilized protein compared to chemical methods. The characterization studies confirmed the presence of common amino acids in recovered sludge protein in significant quantities and heavy metal concentration was reduced after recovery process. The sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed the presence of both low and high molecular weight protein fractions in recovered sludge protein. After establishing the proof-of-concept in the use of recovered sludge protein as wood adhesive, the bonding mechanism of protein adhesives with cellulose substrate was further elucidated in a complementary protein-modification study involving soy protein isolate and its glycinin fractions. The results of this study validated the prevailing bonding theories by proving that surface wetting, protein structure, and type of wood play important role in determining final adhesive strength. Recovered sludge protein was also investigated for its compatibility to formulate hybrid adhesive blends with formaldehyde and bio-based polymers. Apart from chemical cross-linking, the synergy of adhesive blends was evaluated through classical rule-of-mixture. The findings of this study warrants further investigation concerning other potential uses of recovered sludge protein, especially as food supplements and economic implications.
3

Protein Recovery from Secondary Paper Sludge and Its Potential Use as Wood Adhesive

Pervaiz, Muhammad 19 December 2012 (has links)
Secondary sludge is an essential part of biosolids produced through the waste treatment plant of paper mills. Globally paper mills generate around 3.0 million ton of biosolids and in the absence of beneficial applications, the handling and disposal of this residual biomass poses a serious environmental and economic proposition. Secondary paper sludges were investigated in this work for recovery of proteins and their use as wood adhesive. After identifying extracellular polymeric substances as adhesion pre-cursors through analytical techniques, studies were carried out to optimize protein recovery from SS and its comprehensive characterization. A modified physicochemical protocol was developed to recover protein from secondary sludge in substantial quantities. The combined effect of French press and sonication techniques followed by alkali treatment resulted in significant improvement of 44% in the yield of solubilized protein compared to chemical methods. The characterization studies confirmed the presence of common amino acids in recovered sludge protein in significant quantities and heavy metal concentration was reduced after recovery process. The sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed the presence of both low and high molecular weight protein fractions in recovered sludge protein. After establishing the proof-of-concept in the use of recovered sludge protein as wood adhesive, the bonding mechanism of protein adhesives with cellulose substrate was further elucidated in a complementary protein-modification study involving soy protein isolate and its glycinin fractions. The results of this study validated the prevailing bonding theories by proving that surface wetting, protein structure, and type of wood play important role in determining final adhesive strength. Recovered sludge protein was also investigated for its compatibility to formulate hybrid adhesive blends with formaldehyde and bio-based polymers. Apart from chemical cross-linking, the synergy of adhesive blends was evaluated through classical rule-of-mixture. The findings of this study warrants further investigation concerning other potential uses of recovered sludge protein, especially as food supplements and economic implications.
4

Eficiência do processo de ultrafiltração seguido de biodigestão anaeróbia no tratamento de efluente de frigorífico de tilápia

Souza, Milena Alves de [UNESP] 05 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-05Bitstream added on 2014-06-13T21:01:14Z : No. of bitstreams: 1 souza_ma_dr_jabo.pdf: 534415 bytes, checksum: b5ee5194dc95e8eab1f6290e4a93d680 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O presente estudo objetivou a avaliação da eficiência do processo de ultrafiltração seguida da biodigestão anaeróbia no tratamento de efluentes de frigorífico de tilápia. Para tanto, realizada ultrafiltração dos diferentes resíduos gerados no processamento de tilápia (sangria - SG, filetagem - FL e processo contínuo - PC) com membrana de ultrafiltração modelo KOCH, HF1.0-45-XM50 visando avaliar a eficiência da mesma na redução de matéria orgânica, desempenho hidráulico e recuperação proteica. A partir do concentrado obtido na ultrafiltração foi possível avaliar a biodigestão anaeróbia dos diferentes resíduos utilizando estrume bovino como inóculo, estabelecendo quatro tratamentos sendo: sangria, processo contínuo, filetagem e controle, sendo este último composto somente de estrume bovino e água. No processo de ultrafiltração foi possível obter alta remoção de matéria orgânica em todos os efluentes gerados, principalmente em demanda química de oxigênio, nitrogênio total, sólidos suspensos totais e proteína bruta, tendo médias de redução de DQO de 95,21%, 96,21%, 76,26%, NT de 94,74%, 92,49%, 66,54%, SST 96,25%, 94,33%, 83,73% e PB 94,74%, 92,48%, 66,54% para sangria, processo contínuo e filetagem, respectivamente. O desempenho da membrana, medido pelo fluxo de permeado, e a retenção proteica não apresentam diferença significativa entre os tratamentos, sendo a recuperação proteica de 99,99% para todos os tratamentos. Já o concentrado do resíduo de sangria apresentou maior concentração protéica, com média de 70,43%, enquanto os demais tratamentos apresentaram médias de 60,42% e 41,44% para os tratamentos de processo contínuo e filetagem, respectivamente. Para a biodigestão anaeróbia ocorre diferença estatística (P<0,01) entre os tratamentos a partir do 37º dia, tendo o PC com maior produção acumulada, assim como para produção... / This study aimed to evaluate the efficiency of ultrafiltration followed by anaerobic digestion to effluent from tilapia’s frigorific. Therefore, ultrafiltration made of different wastes generated in the processing of tilapia (bleeding - BL, filleting - FL and continuous process - PC) by ultrafiltration membrane model KOCH, HF1.0-45-XM50 to evaluate the efficiency in organic matter redution, hydraulic performance and protein recovery. From the concentrate obtained in the ultrafiltration was possible to evaluate the anaerobic digestion using cattle manure as inoculum, establishing four treatments: bleeding, continuous process control and filleting, the latter being composed only manure and water. In the ultrafiltration process was possible to obtain high removal of organic matter in all effluents generated mainly in chemical oxygen demand, total nitrogen, total suspended solids and crude protein, with average reductions of COD 95.21%, 96.21 %, 76.26%, TN 94.74%, 92.49%, 66.54%, TSS 96.25%, 94.33%, 83.73% and CP 94.74%, 92.48% , 66.54% for bleeding, continuous process and filleting, respectively. The membrane performance, measured by the permeate flux and protein retention were not significantly different between the treatments, and the protein recovery was 99.99% for all treatments. The concentrated residue of bleeding had a higher protein concentration, with an average of 70.43%, while the other treatments had means of 60.42% and 41.44% for the continuous process and filleting, respectively. For the anaerobic digestion could be obtained statistical difference (P <0.01) between the treatments over the 37th day, and the PC with the highest cumulative production, as well as daily production (0,003 m3. biogas.day-1) and production by m3.kg-1 influent (0.0297). For gases composition does not occur difference among treatments, but FL has a higher methane average, with 78.05%, while... (Complete abstract click electronic access below)
5

Eficiência do processo de ultrafiltração seguido de biodigestão anaeróbia no tratamento de efluente de frigorífico de tilápia /

Souza, Milena Alves de. January 2010 (has links)
Resumo: O presente estudo objetivou a avaliação da eficiência do processo de ultrafiltração seguida da biodigestão anaeróbia no tratamento de efluentes de frigorífico de tilápia. Para tanto, realizada ultrafiltração dos diferentes resíduos gerados no processamento de tilápia (sangria - SG, filetagem - FL e processo contínuo - PC) com membrana de ultrafiltração modelo KOCH, HF1.0-45-XM50 visando avaliar a eficiência da mesma na redução de matéria orgânica, desempenho hidráulico e recuperação proteica. A partir do concentrado obtido na ultrafiltração foi possível avaliar a biodigestão anaeróbia dos diferentes resíduos utilizando estrume bovino como inóculo, estabelecendo quatro tratamentos sendo: sangria, processo contínuo, filetagem e controle, sendo este último composto somente de estrume bovino e água. No processo de ultrafiltração foi possível obter alta remoção de matéria orgânica em todos os efluentes gerados, principalmente em demanda química de oxigênio, nitrogênio total, sólidos suspensos totais e proteína bruta, tendo médias de redução de DQO de 95,21%, 96,21%, 76,26%, NT de 94,74%, 92,49%, 66,54%, SST 96,25%, 94,33%, 83,73% e PB 94,74%, 92,48%, 66,54% para sangria, processo contínuo e filetagem, respectivamente. O desempenho da membrana, medido pelo fluxo de permeado, e a retenção proteica não apresentam diferença significativa entre os tratamentos, sendo a recuperação proteica de 99,99% para todos os tratamentos. Já o concentrado do resíduo de sangria apresentou maior concentração protéica, com média de 70,43%, enquanto os demais tratamentos apresentaram médias de 60,42% e 41,44% para os tratamentos de processo contínuo e filetagem, respectivamente. Para a biodigestão anaeróbia ocorre diferença estatística (P<0,01) entre os tratamentos a partir do 37º dia, tendo o PC com maior produção acumulada, assim como para produção... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed to evaluate the efficiency of ultrafiltration followed by anaerobic digestion to effluent from tilapia's frigorific. Therefore, ultrafiltration made of different wastes generated in the processing of tilapia (bleeding - BL, filleting - FL and continuous process - PC) by ultrafiltration membrane model KOCH, HF1.0-45-XM50 to evaluate the efficiency in organic matter redution, hydraulic performance and protein recovery. From the concentrate obtained in the ultrafiltration was possible to evaluate the anaerobic digestion using cattle manure as inoculum, establishing four treatments: bleeding, continuous process control and filleting, the latter being composed only manure and water. In the ultrafiltration process was possible to obtain high removal of organic matter in all effluents generated mainly in chemical oxygen demand, total nitrogen, total suspended solids and crude protein, with average reductions of COD 95.21%, 96.21 %, 76.26%, TN 94.74%, 92.49%, 66.54%, TSS 96.25%, 94.33%, 83.73% and CP 94.74%, 92.48% , 66.54% for bleeding, continuous process and filleting, respectively. The membrane performance, measured by the permeate flux and protein retention were not significantly different between the treatments, and the protein recovery was 99.99% for all treatments. The concentrated residue of bleeding had a higher protein concentration, with an average of 70.43%, while the other treatments had means of 60.42% and 41.44% for the continuous process and filleting, respectively. For the anaerobic digestion could be obtained statistical difference (P <0.01) between the treatments over the 37th day, and the PC with the highest cumulative production, as well as daily production (0,003 m3. biogas.day-1) and production by m3.kg-1 influent (0.0297). For gases composition does not occur difference among treatments, but FL has a higher methane average, with 78.05%, while... (Complete abstract click electronic access below) / Orientador: Rose Meire Vidotti / Coorientador: Jorge de Lucas Júnior / Banca: Aldi Feiden / Banca: Claudinei da Cruz / Banca: Jairo Augusto Campos de Araújo / Banca: Lúcia Helena Sipaúba Tavares / Doutor
6

Optimization of protein concentration from alfalfa juice by high shear rate dynamic filtration / Optimisation de la concentration des protéines à partir du jus de luzerne par filtration dynamique à fort cisaillement

Zhang, Wenxiang 30 June 2016 (has links)
Les protéines extraites des feuilles de luzerne sont une source importante de protéines. La filtration membranaire, technologie de séparation respectueuse de l’environnement avec une productivité élevée et de faible coût a été utilisée pour séparer et concentrer les protéines des feuilles de luzerne à partir de leur jus. Cependant le phénomène du colmatage de la membrane qui réduit sérieusement le flux et la séparation des protéines est un facteur limitant important dans l'application de la filtration membranaire. Pour améliorer la récupération des protéines et amenuiser le phénomène du colmatage, la filtration membranaire associée à fort cisaillement a été utilisée pour la filtration du jus de luzerne. Toujours dans l’objectif d'optimiser le processus de la filtration, "le mode de la filtration" et "les paramètres de fonctionnement" ont été étudiés pour réduire le colmatage de la membrane et améliorer le rendement de la filtration. Puis, l’effluent du jus de luzerne a été filtré par des membranes dans des conditions de fort cisaillement afin de recycler les protéines. En outre, le mécanisme du colmatage a été étudié et a permis d’évaluer les stratégies de contrôle du colmatage. L'optimisation du procédé membranaire, via l’étude du "mode de filtration" et des "paramètres de fonctionnement" a été conduit dans le but d’améliorer la séparation et la concentration des protéines et de réduire le colmatage. Trois types de « mode de filtration » ont été testés : la filtration frontale sur le module de la cellule amicon (DA), la filtration tangentielle dynamique sur le module à disque rotatif (CRDM) et la filtration frontale sur le module à disque rotatif (DRDM)). Les « paramètres de fonctionnement » qui ont été étudiés sont les suivants : le type de membranes (ultrafiltration (UF) et microfiltration (MF)), la vitesse de rotation, la température et la pression transmembranaire (TMP). Le comportement du débit (évolution du flux du perméat au cours de la filtration), les performances de la séparation (taux de clarification et de concentration), l’efficacité du nettoyage de la membrane (récupération de la perméabilité membranaire) et la productivité lors des tests de recyclage et de concentration ont été étudiés dans le but de définir des stratégies dans le contrôle du colmatage. Puis, l’effluent de luzerne a été filtré par UF afin de séparer et purifier les protéines. Le mécanisme du phénomène du colmatage des membranes lors de la filtration du jus de luzerne a été étudié. Le processus du colmatage de la membrane a montré une tendance d’un colmatage multi-site progressif. Le modèle du colmatage multisite progressif selon la loi de Darcy (SMDM) a été proposé afin de mieux décrire et comprendre le processus du colmatage. Les effets de la composition du fluide d’alimentation, du choix de la membrane et des conditions hydraulique ont joué un rôle important dans le processus progressif du colmatage. De plus, les coefficients de résistance et de compressibilité dans les différentes étapes et sites ont été calculés afin d’expliquer le processus complexe du colmatage et d’évaluer l'efficacité des stratégies du contrôle du colmatage. Une série d'essais avec de longues durées de filtration a été réalisée pour étudier le déclin du flux et le colmatage de la membrane à diverses étapes du processus. Ces résultats présentent une utilité pour améliorer la récupération des protéines et contrôler le colmatage dans le processus de la filtration membranaire à fort cisaillement du jus de luzerne. Ces résultats sont aussi utiles pour la conception et la mise en place des technologies membranaires dans les processus industriels. / Alfalfa leaf proteins extracted from plants are an important protein source. As an environmentally friendly separation technology with high productivity and low cost, membrane filtration was used to separate and concentrate leaf protein from alfalfa juice. However membrane fouling seriously reduces flux and protein separation and is an important limitation in the application of membrane filtration. To improve protein recovery and fouling control, dynamic shear-enhanced membrane filtration with high shear rate on membrane surface and excellent anti-fouling capacity was used for alfalfa juice filtration in this work. In order to optimize filtration process, filtration mode and operation parameters were investigated to reduce membrane fouling and improve separation performance. Then, alfalfa wastewater was also treated by dynamic shear-enhanced membrane filtration to recycle proteins. Furthermore, the fouling mechanism was studied and served as a valuable evaluation for fouling strategies. In this study, process optimization including “Filtration mode” and “Operation parameters” was studied to improve protein recovery and fouling control. In “Filtration mode”, three types of filtration modules (dead end filtration using laboratory Amicon cell (DA), dynamic cross filtration using rotating disk module (CRDM) and dead end filtration using rotating disk module (DRDM)) were used to investigate the filtration performance. As for “Operation parameters”, the operation parameters including membranes (ultrafiltration (UF) and microfiltration (MF)), rotating speed, temperature and transmembrane pressure (TMP) were studied to optimize the filtration process. Flux behavior (permeate flux and flux decline), separation performance (clarification and concentration capacity), membrane cleaning efficiency (permeability recovery) and productivity in full recycling tests and concentration tests were utilized to evaluate the various operation strategies. In addition, alfalfa wastewater was treated by UF membrane, while waste proteins were recycled. Fouling mechanism for alfalfa juice filtration was investigated. The fouling process showed significantly stepwise multisite patterns. Based on Darcy’s law, the stepwise multisite Darcy’s law model (SMDM) was proposed to better describe and understand the fouling process. The effects of feed composition, membrane and hydraulic conditions played an important role in stepwise fouling process. Moreover, the resistance coefficient and compressibility for different steps and sites were calculated to explain the complex fouling process and estimate the efficiency of flux decline control strategies. Besides, a series of long tests were utilized to study flux decline and membrane fouling at various fouling step process. These results can be used to understand the protein recovery and fouling control during shear-enhanced membrane filtration process of alfalfa juice. They have important implications for process design of membrane technology in industrial scale.

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