Abstract Studies of phase speciation of trace metals were conducted in Kaohsiung harbor and coastal areas in April and May 2002. Water samples were collected from three different sampling stations to study the spatial distribution of metal species. Colloidal and truly dissolved subsamples were observed by cross-flow filtration treatment. The results show that TOC of seawater samples ranged from 4.17 mg/L to 7.17 mg/L. For trace metals, zinc had the highest concentration(7.21 £gg/L ¡ã14.14 £gg/L), followed by manganese(3.31 £gg/L ¡ã 11.73 £gg/L), copper(0.28 £gg/L ¡ã 7.57 £gg/L), lead(2.41 £gg/L ¡ã 4.41 £gg/L), nickel(1.78 £gg/L ¡ã 2.97 £gg/L). Highest concentrations of TOC and metals were observed in Kaohsiung harbor(S1), and the values decreased in the order of S1 ¡Ö S2 ¡Ö S3. Distribution of phase speciation of trace metals varied with location. Nickel existed in truly dissolved phase predominately(66 ¢Mat S1, 79.7 ¢Mat S2 and 84.6 ¢Mat S3). For the other metals, either particle or truly dissolved phase was the major species at each sampling station. For zinc, 56.1 ¢Mat S1 was in truly dissolved phase, 68.1 ¢Mat S2 and 59.6 ¢M at S3 were in particulate phase. For copper, 67.5 ¢Mat S1 was in particulate phase, 56.7 ¢Mat S2 and 89.9 ¢Mat S3 were in truly dissolved phase. For manganese, 56.3 ¢Mat S1 was in truly dissolved phase, 79.8 ¢Mat S2 and 72.1 ¢Mat S3 were in particulate phase. For lead, 51.7 ¢Mat S1 and 66.0 ¢Mat S3 were in truly dissolved phase, 63.5 ¢Mat S2 was in particulate phase. The percentages of TOC and metals in colloidal phase of the filter-passing pool were low at all sampling stations and decreased in the order of S1 ¡Ö S2 ¡Ö S3. They were found predominately in truly dissolved fraction. The results also show that Kaohsiung harbor (S1) had the highest percentage of colloidal fraction, followed by coastal water (S2), open sea (S3). Values of partition coefficient between colloids and true solution(Kc ) in the Kaohsiung harbor and nearby coastal areas were lower than the Kc values observed in Galveston Bay during July 1995.

The tap-water treated by water treatment plants in southern Taiwan is coming from surface water of the rivers, subsurface stream and underground water of deep wells. The original raw water possesses were high level of hardness and ammonia- nitrogen solute due to affection by terrain, geology and human activities within water origin area. And considering the water quality from Kao-ping river origin is hard to control during in rain fall and dry season, we were to construction efficiency procedure of water treatment to obtain a high quality of drink water. There were high hardness and TDS from strata limestone of groundwater to increase treatment difficulty in southern Taiwan water treatment plant. Therefore, recommended that the influent water standards were limited hardness and silicate (SiO2) less than 300 mg/L and 15 mg/L, respectively. On the other hand, the metal substances Ca, Mg, Si and Al in influent water were 74.3 mg/L, 18.7 mg/L, 12.9 mg/L and 0.1 mg/L, respectively. Results show high inorganic substances that could increase the treatment loading. This project of the study, were make sure the problem of membrane clogging and fouling happened to the finest water treatment plants who use LPRO membrane system to remove the impurity in the influent water. Moreover, by accumulation of processes operation experience on site were according to water quality statistics data and membrane autopsy of single LPRO membrane by processes. In the same time, we prepared three single tube of RO membrane to experiment on site and collected data from before and after antifouling additive, that could find the membrane fouling and clogging results of the influent raw water. Obviously, the influent raw water quality into LPRO membrane is closely connected to the efficiency of treatment plant. The results show when the temperature decreased of influent raw water that could decrease the effluent volume from LPRO, because the water temperature affected by increase viscosity of raw water. The first part clogging substances of membrane were aluminum (Al), that could be use aluminate coagulant to make increase more aluminum. And the TOC value of the effluent were from 0.2 to 1.4 mg/L, that shows the effluent water was kept stably but UV254 value were have more than 75% efficiency. Results of organic analysis on LPRO effluent indicates the pretreatment process could leave annular structure organic. In other hand, when using EEFM to analysis the spectra sampling of organic of LPRO, there finding a lot low emission wavelength fluoresces of influent on EX/EM 230/340 and decrease the wavelength fluoresces value on EX/EM 280/330 and 240/340 by RO membrane system of LPRO. To be worth mentioning, when organism of sampling fluoresces value during high emission wavelength on EX/EM 240/400 nm was disappeared, that indicates RO membrane has good performance to separation organism of water. And results of elements analysis on RO membrane surface were using SEM and EDX have a lot aluminum and silicate on segment RO membrane module. Therefore, results show pretreatment process of coagulation and sedimentation could not treatment metal substances and organic efficiency, that was to effect directly cause to make the problems of membrane fouling and clogging.

No description available.

This research is a follow up to preliminary studies reported by Beier and Sego (2008) and the objective is to investigate laboratory scale dewatering of oil sands total tailings using cross flow filtration technology. A laboratory experiment was setup in Oil Sands Tailings Research Facility and tests were carried out under different operational conditions using different tailings. The experiments showed clean filtrate water generated under all test conditions. Coarser tailings and higher filter pipe porosity resulted in greater filtrate flux rate. The effect of slurry velocity, residual bitumen, and transmembrane pressure on cross flow filtration performance was also evaluated. A dimensional analysis was developed using the laboratory tests to establish the relationships between measured parameters and to assist and guide future experimental programs. / Geotechnical Engineering

Studies of phase speciation of trace metals were conducted in Kao-ping river estuary in September 2001 and May 2002. Influence of seasonal variation, salinity and organic carbon content on the trace metal¡¦s phase speciation were of special interest. Water samples collected from four different sampling stations were analyzed for their contents which include salinity, pH value, dissolved oxygen, turbidity, total organic carbon and trace metals. Subsamples observed by cross-flow filtration treatment were further analyzed for the contents of total organic carbon and trace metals. The results showed that manganese has the highest concentration( 8.23 ~ 291.24 £gg/L ), followed by zinc( 2.83 ~ 5.89 £gg/L), nickel( 1.69 ~ 5.82 £gg/L ), copper( 1.75 ~ 4.71 £gg/L ), lead( 0.27 ~ 0.89 £gg/L ) and cadmium( 0.01 ~ 0.27 £gg/L ). Cadmium existed in particulate phase predominately. Copper existed in truly dissolved phase predominately. Particle and truly dissolved phase were the major species of zinc, nickel, manganese and lead. Percentage of all metals in colloidal fraction of the filter-passing pool were low( 9 ~ 16 % for Cu, 5 ~ 21 % for Zn, 4 ~ 30 % for Ni, 2 ~ 38 % for Mn, 5 ~ 30 % for Pb and 8 ~ 34 % for Cd ), they were found predominately in truly dissolved fraction. Effect of seasonal variation was not significant on the distribution of trace metals. Percentage of all truly dissolved metals increased with increasing salinity, however, percentage of particulate metals decreased with increasing salinity ( except for Zn ). Values of partition coefficients between colloids and true solution( Kc ) were considerably higher than those between particles and true solution( Kp ) for all trace metals indicate a high complexation capacity and binding intensity of colloidal organic matter.

Mikrosiebe stellen auf Grund ihrer Geometrie einen geringeren Strömungswiderstand im System dar und ermöglichen somit eine höhere Filtrationsgeschwindigkeit. Der Einsatz solcher Mikrosiebe anstelle herkömmlicher Membranen in Filtrationsprozessen kann deren Effizienz enorm steigern. Im Rahmen der Diplomarbeit wurden mittels partikelassistierter Benetzung hergestellte Mikrosiebe charakterisiert. Hierfür wurde zunächst ein Filtermodul für Kreuzstromfiltrationen entwickelt, welches anschließend in einen Versuchsaufbau integriert und charakterisiert wurde. Neben den Strömungswiderständen der rechteckigen Kanäle des Moduls wurde außerdem der Strömungswiderstand für Mikrosiebe einer Porengröße bestimmt und mit der Theorie verglichen. Es zeigt sich, dass Theorie und Praxis gut übereinstimmen und es sich bei dem entwickelten Versuchsaufbau um eine gute Methode handelt Strömungswiderstände von Mikrosieben zu bestimmen.

O processo de microfiltração tangencial com membranas tubulares inorgânicas e tubos microporosos, respectivamente de origem importada e nacional, foi investigado tendo-se como objeto de separação as misturas macromoleculares preparadas com os agentes polissacarídeos gomas Xantana e Guar em suspensão aquosa. São evidenciados neste processo os efeitos de sinergia compreendidos nas misturas elaboradas puras e em diferentes proporções, na concentração final de 1000 ppm. A investigação experimental acompanha o comportamento reológico de cada mistura ao longo do processo e os resultados foram investigados a partir de propriedades físico-químicas relevantes como: concentração de carbono orgânico total (Total Organic Carbon - TOC) e análise de absorbância no espectômetro de infravermelho. Resultados de TOC indicaram que em apenas um meio filtrante tubular microporoso (C1T+), o desempenho do processo na retenção dos polissacarídeos foi acima de 90%, em relação ao processo com a membrana comercial importada cuja retenção de TOC foi da ordem de 80%. De acordo com as análises de absorbância, conclui-se que as membranas com tamanho do poro nominal de 0,2 \'mü\'m e 0,4 \'mü\'m tiveram uma retenção mais eficiente do que os tubos microporosos em estudo. A temperatura foi um parâmetro significativo, pois a retenção, na maioria dos casos, foi maior na temperatura de 25ºC, independente da pressão e da velocidade média. Na análise dos procedimentos envolvendo cada mistura, foi constatada a boa sinergia entre as gomas, sem modificação de estrutura (formação de gel) ou fenômenos de superfície que impedissem o processo de microfiltração. A vazão transmembrana das misturas ficou limitada entre os máximos valores para mistura pura de Xantana e mínimos para Guar. Todas as misturas apresentaram comportamento pseudoplástico, sem mudanças na reologia, reforçando a adequada sinergia quanto a este aspecto. / The present dissertation reports cross-flow microfiltration with national and imported inorganic tubular membranes and microporous tubes. The object of separation is the macromolecular mixtures prepared with polysaccharide agents Xanthan and Guar gum in aqueous solution. The process shows the synergism effects in pure and different mixture proportions, with 1000 ppm final concentration. The experiments established the rheologic behaviour of each mixture along the process and significant physical and chemical properties, such as Total Organic Carbon concentration (TOC) and absorbency analysis in infrared spectrometer were analyzed. TOC retention shows that only one microporous tubular filtering medium (C1T+) had better performance (retention 90%) than the imported commercial membrane (retention about 80%). Absorbency analysis show a better retention efficiency of membranes with pore size of 0,2 \'mü\'m and 0,4 \'mü\'m than microporous tube. The temperature was a significant parameter, as the better retention was obtained at 25ºC, independently of pressure and mean velocity. There is good synergism between Xanthan and Guar gums without structure modifications or surface phenomena that would impede the microfiltration process. The transmembrane flux of proportional mixtures has been limited between maximum values of pure Xanthan and minimum values of pure Guar mixtures. All mixtures have pseudoplastic behaviour, without changes in rheology, intensifying the good synergism.

O processo de microfiltração tangencial com membranas tubulares inorgânicas e tubos microporosos, respectivamente de origem importada e nacional, foi investigado tendo-se como objeto de separação as misturas macromoleculares preparadas com os agentes polissacarídeos gomas Xantana e Guar em suspensão aquosa. São evidenciados neste processo os efeitos de sinergia compreendidos nas misturas elaboradas puras e em diferentes proporções, na concentração final de 1000 ppm. A investigação experimental acompanha o comportamento reológico de cada mistura ao longo do processo e os resultados foram investigados a partir de propriedades físico-químicas relevantes como: concentração de carbono orgânico total (Total Organic Carbon - TOC) e análise de absorbância no espectômetro de infravermelho. Resultados de TOC indicaram que em apenas um meio filtrante tubular microporoso (C1T+), o desempenho do processo na retenção dos polissacarídeos foi acima de 90%, em relação ao processo com a membrana comercial importada cuja retenção de TOC foi da ordem de 80%. De acordo com as análises de absorbância, conclui-se que as membranas com tamanho do poro nominal de 0,2 \'mü\'m e 0,4 \'mü\'m tiveram uma retenção mais eficiente do que os tubos microporosos em estudo. A temperatura foi um parâmetro significativo, pois a retenção, na maioria dos casos, foi maior na temperatura de 25ºC, independente da pressão e da velocidade média. Na análise dos procedimentos envolvendo cada mistura, foi constatada a boa sinergia entre as gomas, sem modificação de estrutura (formação de gel) ou fenômenos de superfície que impedissem o processo de microfiltração. A vazão transmembrana das misturas ficou limitada entre os máximos valores para mistura pura de Xantana e mínimos para Guar. Todas as misturas apresentaram comportamento pseudoplástico, sem mudanças na reologia, reforçando a adequada sinergia quanto a este aspecto. / The present dissertation reports cross-flow microfiltration with national and imported inorganic tubular membranes and microporous tubes. The object of separation is the macromolecular mixtures prepared with polysaccharide agents Xanthan and Guar gum in aqueous solution. The process shows the synergism effects in pure and different mixture proportions, with 1000 ppm final concentration. The experiments established the rheologic behaviour of each mixture along the process and significant physical and chemical properties, such as Total Organic Carbon concentration (TOC) and absorbency analysis in infrared spectrometer were analyzed. TOC retention shows that only one microporous tubular filtering medium (C1T+) had better performance (retention 90%) than the imported commercial membrane (retention about 80%). Absorbency analysis show a better retention efficiency of membranes with pore size of 0,2 \'mü\'m and 0,4 \'mü\'m than microporous tube. The temperature was a significant parameter, as the better retention was obtained at 25ºC, independently of pressure and mean velocity. There is good synergism between Xanthan and Guar gums without structure modifications or surface phenomena that would impede the microfiltration process. The transmembrane flux of proportional mixtures has been limited between maximum values of pure Xanthan and minimum values of pure Guar mixtures. All mixtures have pseudoplastic behaviour, without changes in rheology, intensifying the good synergism.

Dans un contexte d’augmentation des volumes de boues résiduaires produits, comprendre et optimiser les processus de déshydratation mécanique est crucial. Leurs performances conditionnent tant le fonctionnement global de la station que son bilan environnemental et économique. En effet, la siccité des boues déshydratées impacte fortement les procédés ou filières permettant leur valorisation à l’échelle des territoires (compostage, valorisation agronomique directe, incinération, …) ainsi que leur bilan environnemental direct et indirect (tonnages à transporter, ...). De plus, les filtrats devront être traités par la station, et leur composition influence significativement le fonctionnement de la filière de traitement des eaux. Les filtres-presses font partie des procédés de déshydratation mécanique les plus utilisés dans les filières boues des stations d’épuration des eaux usées. Leurs performances sont fonction à la fois de leurs paramètres de fonctionnement et des propriétés de la boue à déshydrater. Les connaissances actuelles sont cependant insuffisantes pour permettre (1) d’expliquer pourquoi certaines boues se déshydratent mieux que d’autres et (2) de relier ces phénomènes aux processus mis en oeuvre lors de la déshydratation mécanique. Le poste de déshydratation fonctionne ainsi comme une boîte noire à partir de laquelle il est difficile de prédire les performances d’un outil de déshydratation appliqué à une boue particulière et d’anticiper des dysfonctionnements. Dans ce contexte, l’objectif de ce travail de thèse était de comprendre quels sont les facteurs de contrôle des performances de la déshydratation mécanique des boues d’épuration en filtre-presse et comment ces derniers impactent le fonctionnement du procédé. Dans un premier temps, l’impact des paramètres de fonctionnement des filtres-presses sur leurs performances a été étudié en cellule de filtration tangentielle (cellule de laboratoire reproduisant les processus d’un filtre presse industriel). Ce travail a permis de hiérarchiser les paramètres opératoires selon leur impact sur les performances de déshydratation. Cette étude a permis de mettre en évidence que le paramètre le plus sensible est l’épaisseur de gâteau suivi de la pression. L’impact de ces paramètres est en partie lié à celui du gradient de pression sur les équations de la filtration même si ce dernier doit être considéré en 3D pour expliquer les résultats observés. Dans un second temps l’étude de l’impact des propriétés des boues sur les performances de déshydratation a été réalisée. Pour ce faire, ce travail s’est focalisé sur l’impact d’un des procédés qui modifie le plus les propriétés des boues : la digestion anaérobie. L’objectif de ce travail était d’identifier comment le temps de séjour hydraulique (TSH) appliqué dans le digesteur influence les propriétés physicochimiques des boues et les performances de déshydratation évaluées au travers d’essais de déshydratation en cellule de filtration tangentielle. Cette phase a permis de montrer que quand le TSH augmente de 0 à un TSHcritique, la déshydratabilité de la boue diminue. Au-delà de ce TSHcritique, cette dernière s’améliore sans pour autant atteindre celle de la boue brute. Ces phénomènes ont pu être reliés à une modification des équilibres osmotiques entre les flocs et le milieu interstitiel couplée à une modification de la matrice d’exopolymères solubles des flocs. Enfin, un modèle numérique permettant de simuler la déshydratation des boues résiduaires a été implémenté sous COMSOL multiphysics®. Au travers des processus modélisés, il prend en compte les principaux facteurs de contrôle des performances identifiés auparavant. Après ajustement des paramètres sur un unique essai de déshydratation à une pression donnée, le modèle permet de prédire la siccité du gâteau pour une pression comprise entre 3 et 15 bars. / As more and more sewage sludge are generated, understanding and optimization of mechanical dewatering processes is crucial. Their performances affect both plant management and its environmental and economic impacts. Indeed, dryness of dewatered sludge strongly impacts processes for agronomic and energetic recovery (composting, direct agricultural recycling, incineration ...) and their direct and indirect environmental impacts (volumes to transport...). In addition, the filtrates have to be treated by the wastewater treatment plant, and their composition significantly affects its operating. Filter presses are one of the most common mechanical dewatering processes operated for sludge treatment in wastewater treatment plant. Their performance depends on their operating parameters and sludge properties. However, current knowledge is insufficient (1) to explain why some sludges are easier or harder to dewater than others, and (2) to link these phenomena to processes that carry out during the mechanical dewatering. Hence, dewatering works like a black box from which it is difficult to predict the efficiency of a dewatering tool performed with a particular sludge and to anticipate operating problems. In this context, the objective of this thesis was to understand witch factors drive the efficiency of mechanical dewatering of sewage sludge in the filter press and how they impact the process. First, the impact of operating parameters of filter presses on their efficiency was investigated in cross-flow filtration cell (lab-scale cross-flow filtration cell reproducing processes that occur in an industrial filter press). This work allowed the classification of the operating parameters according to their impact on the dewatering performances. This study highlighted that the most sensitive parameter is the cake thickness followed by pressure. The impact of these parameters is partially linked with their influence on the pressure gradient even if it should be considered in 3D to explain the results. Secondly, the study of the impact of sludge properties on dewatering performances was carried out. In this thesis, this work focuses on the impact of one of the processes which modifies most significantly sludge properties: anaerobic digestion. The objective of this work was to identify how hydraulic retention time (HRT) in the digester affects physicochemical properties of sludge and dewatering performance. Results demonstrated that when the HRT increases from 0 to a critical HRT (HRTcritical), sludge dewaterability decreases. Beyond this HRTcritical, it increases without reaching cake dryness of the raw sludge. These phenomena could be linked to a change in osmotic balance between the flocs and the bulk solution, combined with a modification of the soluble exopolymer matrix of flocs. Finally, a numerical model, allowing the simulation of sludge dewatering was implemented with COMSOL multiphysics®. Equation system takes into account the main factors that affect performances previously identified. After parameter calibration on a single dewatering experiment at 8 bars, the model allows the prediction of cake dryness for any pressure between 3 and 15 bars.

<p>U radu je ispitivana mogucnost unapređenja membranske filtracije mleka primenom promotora turbulencije razlicitog geometrijskog oblika i dimenzije. Eksperimentalna istraživanja su izvedena na keramickoj membrani velicine 100 nm koja se najce&scaron;ce koristi u procesu mikrofiltracije mleka. Istraživanja su obuhvatila ispitivanje uticaja<br />promotora helikoidne geometrije (uvrnuta traka i Keniks mikser) i geometrije u obliku seciva (Koflo mikser) razlicitih karakteristicnih dimenzija na fluks permeata, prljanje i selektivnost membrane. Efikasnost primene razlicitih promotora analizirana<br />je kako sa aspekta povecanja fluksa tako i sa aspekta smanjenja potro&scaron;nje energije.<br />Istraživanje uticaja tipa promotora turbulencije na mikrofiltraciju proteina mleka<br />pokazalo je da se izborom geometrije, karakteristicne dimenzije i radnih uslova mogu<br />postici znacajna i energetski isplativa povecanja fluksa permeata.<br />Primenom uvrnute trake kao promotora Uticaj tipa promotora turbulencije na unapređenjemembranskefiltracije tubulencije ostvarena su povecanja fluksa i od 200<br />do 600% u zavisnosti od karakteristicne dimenzije uvrnute trake, i rad pri dva ili tri puta manjim protocima u odnosu na rad bez promotora. Najvece povecanje fluksa od oko 600% ostvareno je primenom najgu&scaron;ce uvrnute trake karakteristicne dimenzije 1,0 (UT1,0). UT1,0 kao promotor turbulencije uzrokuje najvece ubrzanje fluida tj. nivo turbulencije i najdužu helikoidnu putanju strujnica &scaron;to doprinosi intenzivnom odno&scaron;enju cestica sa povr&scaron;ine membrane. Ispitivanje primene Keniks miksera kao<br />promotora turbulencije je pokazalo da se znacajna i isplativa povecanja fluksa postižu vec pri veoma malim protocima. Keniks mikser je takođe helikoidne geometrije kao i uvrnute trake, ali se razlikuje po tome &scaron;to su helikoidni elementi<br />postavljeni pod uglom od 90o i levo desno jedan u odnosu na drugi. Ovakva orjentacija elemenata uzrokuje preraspodelu i promenu smera stujnica posle svakog elementa zbog cega je pad pritiska za Keniks mikser i do cetiri puta veci u odnosu na<br />uvrnutu traku iste karakteristicne dimenzije, ali uz veci utro&scaron;ak energije. Promotori geometrije u obliku seciva (Koflomikseri) takođe obezbeđuju povecanje fluksa od<br />200 do 650% pri nižem protoku u odnosu na rad bez promotora. Vece povecanje fluksa od 500 do 600% postignuta su primenom Koflo miksera manje karakteristicne dimenzije 1,3. Koflo mikseriobezbeđuju promenu slike strujanja u membrani koja se manifestuje takođe raspodelom toka fluida i pojavom helikoidnih strujnica, ali i sudaranjem i me&scaron;anjem struja usled udara o seciva pod određenim uglom. Po sudaranju struja se ovaj tip miksera razlikuje u odnosu na uvrnute trake i Keniks mikser. Ipak pad pritiska ovog miksera je veci u odnosu na pad pritiska uvrnute trake, a manji u odnosu na pad pritiska Keniks miksera. Ispitivanje smanjenja prljanja membrane pokazalo je da se primenom promotora smanjuje otpor prljanja membrane kao i otpori usled povratnog i nepovratnog prljanja. Naročito je zapaženo smanjenje otpora usled povratnog prljanja koje se javlja na povr&scaron;ini membrane. Na ovaj nacin potvrđeno je da svi tipovi miksera uzrokuju promenu nacina strujanja u membrani koja obezbeđuje pobolj&scaron;anje prenosa mase u graničnom sloju. U granicnom sloju najintenzivnije deluje Uticaj tipa promotora turbulencije na unapređenje membranske filtracije. Keniks mikser kod kog sem preraspodele stujanja dolazi i do promene smera strujnica nakon svakog elementa. Izvođenje procesa primenom promotora je energetski isplativije u odnosu na konvencionalan nacin rada i važi za sve ispitivane tipove promotora bez obzira na geometriju i karakterističnu dimenziju. Za vrednosti flukseva do 60 Lm-2h-1 uvrnute trake sve tri karakteristicne dimenzije zahtevaju istu potro&scaron;nju energije. Primena uvrnute trake UT1,0 je najisplativija za flukseve vece od 60 do 100 Lm-2h-1 iako uzrokuje veci pad pritiska u odnosu na UT1,5 i UT2,5, ali obezbeđuje i proporcionalno veci fluks pri protocima tri puta manjim u odnosu na rad bez promotora. Primenom UT1,0 moguće su u&scaron;tede energije u rasponu od 50 do 75 % u odnosu na rad bez promotora. Potro&scaron;nja energije kod primene Keniks miksera je veća u odnosu na uvrnutu traku iste karakterisitčne dimenzije, a opseg radnih protoka i TMP uslovljen velikim padom pritiska. U&scaron;tede energije u slučaju primene Keniks miksera su od 30 do 65% u odnosu na rad bez promotora. Međutim, primenom UT1,0 umesto Keniks miksera iste dimenzije obezbeđuju se od 10 do 35 % vece u&scaron;tede energije pri istom radnom fluksu. Sa aspekta potro&scaron;nje energije, Koflo mikseri su najmanje efikasni. KF1,3 mikser je manje efikasan u odnosu na KF2,5 zbog većeg pada pritiska i ne proporcionalno veceg fluksa. Primenom ovih promotora se postižu u&scaron;tede energije od 20 do 70% u odnosu na konvencionalan način rada, ali je ipak njihova efikasnost manja u odnosu na uvrnutu traku iste dimenzije zbog razlike u padu pritiska Pravilnim izborom geometrije promotora može postici povecanje fluksa uz nisku potro&scaron;nju energije odnosno niže padove pritiska. Slika strujanja koja zavisi od geometrije promotora najvi&scaron;e utice na povecanje fluksa pri čemu je najbitnije da se pored povećanja brzine obezbedi pojave strujnica helikoidnog oblika u graničnom sloju. Upravo ovakav nacin strujanja najvi&scaron;e doprinosi odno&scaron;enju cestica istaloženih na povr&scaron;ini membrane i povecanju prenosa mase. Pojave radijalnog me&scaron;anja ili sudaranja struja mogu se smatrati sporednim pojavama u odnosu na to koliko doprinose povecanju fluksa međutim, njihovo postojanje doprinosi povećanju pada pritiska i smanjuju energetsku efikasnost promotora. Uticaj tipa promotora turbulencije na unapređenje membranske filtracije. Rezultati istraživanja su potvrdili polaznu pretpostavku, definisanu ciljem istraživanja, da helikoidna putanja strujanja kod uvrnutih traka obezbeđuje najintenzivnije odno&scaron;enje istaloženog materijala sa povr&scaron;ine membrane uz najmanji pad pritiska odnosno gubitak energije. Sa druge strane, pojava me&scaron;anja koje je primarno kod Keniks i Koflo miksera izaziva, pored odno&scaron;enja istaloženih čestica i dodatno vrtloženje koje za posledicu ima veći pad pritiska i manju energetsku efikasnost.</p> / <p> This work investigates influence of tubulence promotor geometry and its characteristic dimension on the improvement of membrane filtration of milk proteins. The investigation was performed using a ceramic tubular membrane with 100 nm pore size which is commonly used in the dairy industry. As turbulence promoters two main geometry types were chosen: a helical (twisted tape and Kenics mixer) and a blade shaped (Koflo mixer). Except the geometry type, influence of an aspect ratio was studied, also. Efficiency of turbulence promoters was evaluated from the point of view of flux improvement and specific energy consumption. The experimental results clearly show that microfiltration process can be improved by proper choice of a turbulence promoter geometry, its aspect ratio and operating conditions. The process efficiency is increased by achievement of a significant flux increase and lowered energy consumption. Application of twisted tapes as turbulence promoters yields in the flux improvement of 200 to 600% depending on the aspect ratio of twisted tape but at two or three times lower cross-flow rates compared to conventional MF. The higher flux improvement of 600% was achieved by using twisted tape with aspect ratio 1.0, which induces the highest turbulence and the longest helical stream path so the scouring of particles from the membrane surface is the most intensive.<br /> By applying Kenics mixer as turbulence promoter significant flux improvement can be<br /> achieved at five fold lower cross-flow rates. Kenics mixer is also helical insert but its elements are right and left-hand orientated what causes the local resistances and much higher pressure drop compared to the twisted tape of the same aspect ratio. This resulted in higher energy consumption and in lower efficiency of the process fitted with Kenics mixer. Application of blade type insert, such is Koflo mixer, enables flux improvement of 200 to 650% and operation at lower cross-flow rates compared to conventional MF. The higher flux improvement, 500 to 600%, was yielded using the<br /> mixer of lower aspect ratio, 1.3. Blade mixers divide and redistribute streamlines after each element and also induce helical flow path near the membrane surface. Flow field defers from the flow field of twisted tape and Kenics mixer by the appearance of stream collision in the center of blade structure. This causes grater pressure gradient than for the twisted tape but lower than for the Kenics mixer. Investigation of membrane fouling confirmed that the membrane fitted with promoter is less fouled compared to the plane membrane. The reversible fouling resistance is reduced for<br /> order of magnitude especially for the case of Kenics mixer application. All types of promoters improve the mass transfer in the boundary layer at membrane surface inducing the helical path streamlines which take away deposited material. Energy consumption analysis has shown that the energy consumption can be significantly<br /> reduced by proper promoter geometry and aspect ratio. Operation with promoters proved to be more efficient from energy consumption point of view compared to the conventional operation. Using twisted tape of 1.0 aspect ratio energy can be saved for 50 to 75%. Blade type mixers are the less efficient, but still more efficient than the<br /> conventional filtration. In general, when the twisted tapes were used as promoters generated helical streamline path enables the most intensive fouling reduction with lowest pressure drop i.e. energy consumption. On the other hand, when the Kenics<br /> and blade mixers were used, except helical streamline path the secondary flows and mixing are induced what along with fouling reduction causes the higher pressure loss making these promoters energetically less efficient.</p>