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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.
361

Influencia da ultrafiltração intra-operatoria na retirada de interleucinas, fator de necrose tumoral-alfa e na função pulmonar em pacientes submetidos a revascularização do miocardio com circulação extracorporea / Influence of intra-operative ultrafiltration on the seric interleukins, tumor necrosis factor alpha and pulmonary function in patients submitted myocardial revascularization with cardiopulmonary by pass

Kosour, Carolina 15 August 2018 (has links)
Orientadores: Desanka Dragosavac, Luis Alberto Magna / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-15T12:28:06Z (GMT). No. of bitstreams: 1 Kosour_Carolina_D.pdf: 5835134 bytes, checksum: f6d1efdf0f5f0705f3ba5432ea02cab5 (MD5) Previous issue date: 2010 / Resumo: Introdução: A operação cardíaca com utilização da circulação extracorpórea (CEC) está associada ao desenvolvimento da resposta inflamatória sistêmica e, como conseqüência, à disfunção pulmonar. O uso de ultrafiltração no intra-operatório tem sido proposto para remoção dos mediadores inflamatórios liberados durante a CEC, na tentativa de minimizar a resposta inflamatória. Objetivo: Avaliar o efeito da ultrafiltração nos níveis séricos de interleucinas, fator de necrose tumoral-alfa e na função pulmonar de pacientes submetidos à revascularização do miocárdio. Método: Foi realizado um estudo clínico, prospectivo, randomizado, com 40 pacientes, divididos em dois grupos, em um hospital terciário. Um grupo foi submetido à ultrafiltração (UF) durante a CEC e outro grupo (controle), não. Foram mensurados interleucinas (IL-ip, IL-6, IL-8), fator de necrose tumoral alfa (TNF-a), índices de troca gasosa pulmonar [PaO2/FiO2, D(A-a)O2 e VD/VT] e mecânica ventilatória (Cst e Raw) nos períodos pré-operatório, intra-operatório e dois dias de pós-operatório. As interleucinas e TNF-a foram analisadas também no perfusato, no grupo teste. Resultados: Houve aumento de IL-ip (30 minutos após a CEC e 12 horas após a operação) e IL-6 (24 e 36 horas após a operação) no grupo UF comparado ao grupo controle. Houve aumento de IL-6 em todos os tempos comparados ao tempo inicial, em ambos os grupos. Foi observada diminuição da IL-8 cinco minutos antes da CEC e aumento seis, i2, 24, e 36 horas após operação, além de aumento de TNF-a nos tempos 30 minutos após CEC, 24, 36 e 48 horas após operação. Na análise do líquido ultrafiltrado foi identificada a presença de TNF-a e das demais IL-ip, IL-6, IL-8, somente em traços. Na função pulmonar, houve piora da PaO2/FiO2, D(A-a)O2, VD/VT, cinco minutos antes da CEC, além da diminuição da D(A-a)O2 30 minutos após CEC, seis,i2, 24 e 36 horas após operação. Houve aumento da complacência estática pulmonar (Cst) e queda da resistência de vias aéreas (Raw) cinco minutos antes da CEC, além da queda da Raw seis horas após a operação nos dois grupos. Conclusão: A utilização de ultrafiltração aumentou o nível sérico das IL-i e IL-6, não interferindo na troca gasosa e na mecânica pulmonar de pacientes submetidos à revascularização do miocárdio / Abstract: Introduction: Cardiac surgery with cardiopulmonary bypass (CPB) is associated with the development of systemic inflammatory response and, in consequence, pulmonary dysfunction. The use of ultrafiltration intraoperatively has been proposed to remove inflammatory mediators released during CPB in an attempt to minimize the inflammatory response. Objective: Evaluating the effect of ultrafiltration on the serum levels of interleukin, tumor necrosis factor alpha and pulmonary function in patients undergoing myocardial revascularization. Methods: It was carried out a prospective randomized clinical trial on 40 patients divided into two groups, in a tertiary hospital. One group was submitted to ultrafiltration (UF) during CPB whereas the other group (control), was not. It were mensured interleukins (IL-ip, IL-6, IL-8), tumor necrosis factor alpha (TNF-a), pulmonary gas exchange indexes [PaO2/FiO2, D(A-a)O2 and VD/VT] as well as respiratory mechanics (Cst e Raw) in the preoperative and intraoperative periods and postoperatively. The interleukins and TNF-a were also analyzed in the perfusate in the test group. Results: There was an increase in IL-ip (30 minutes after CPB and 12 hours after surgery) and in IL-6 (24 and 36 hours after surgery) in the UF group by comparison with the control one. There was also an increase in IL-6 at all schedulled times compared to the initial period in both groups. It was noticed a decrease in IL-8 five minutes before CPB and an increase six, i2, 24 and 36 hours after surgery in addition to an increase in TNF- a at the times 30 minutes after CPB, 24, 36 and 48 hours after surgery. On analyzing the ultrafiltrated fluid it was identified the presence of TNF-a and the other IL-ip, IL-6, IL-8 only in traces. Regarding pulmonary function, there was a worsening of PaO2/FiO2, D(A-a)O2, and VD/VT five minutes prior to CPB in addition to a decrease in D(A-a)O2 30 minutes after CPB, six, 12, 24 and 36 hours after surgery. There was an increase in the pulmonary static compliance, and a fall of the airway resistance five minutes before CPB. Also, there was a fall of the airway resistance six hours after surgery in both groups. Conclusion: The use of ultrafiltration has increased the serum levels of IL-1 and IL-6 without interfering with the pulmonary gas exchange and respiratory mechanics in patients undergoing myocardial revascularization / Doutorado / Pesquisa Experimental / Doutor em Cirurgia
362

Aproveitamento de diferentes tipos de soro de leite na elaboração de bebidas lácteas acidificadas carbonatadas

Boccia, Juliana Nogueira 25 May 2018 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-07-04T13:35:00Z No. of bitstreams: 0 / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-07-04T14:22:18Z (GMT) No. of bitstreams: 0 / Made available in DSpace on 2018-07-04T14:22:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-05-25 / A proposta deste estudo foi oferecer novas alternativas para o aproveitamento sustentável do soro desproteinado através do desenvolvimento e disponibilização de tecnologias simples de fabricação de bebidas lácteas acidificadas carbonatadas, com vida útil estendida, sem a utilização de tratamentos térmicos extremos. Foram utilizados três diferentes tipos de soros desproteinados (permeado de ultrafiltração, soro de ricota e soro ácido obtido da fabricação de queijos coagulados por acidificação direta), que normalmente são descartados pelas indústrias de laticínios. Para cada tipo de soro foram produzidas bebidas acidificadas carbonatadas em 3 repetições que foram analisadas ao longo do período de 60 dias. Verificou-se diferenças significativas entre as bebidas em relação á acidez, pH e viscosidade. Porém, para cada bebida, não houveram diferenças significativas em relação ao tempo, o que significa que permaneceram estáveis sob esses aspectos durante os 60 dias de armazenamento. Entretanto, pôde - se observar a deposição de proteínas que iniciou entre 20 e 30 dias de estocagem , em razão do pH baixo, e à perda de capacidade do estabilizante de manter essas proteínas dispersas. Os produtos apresentaram estabilidade microbiológica durante todo o tempo de estocagem sob refrigeração, não apresentando contagem de microrganismos patogênicos, confirmando assim a eficácia das barreiras microbiológicas aplicadas (pH, tratamento térmico e dióxido de carbono). As análises sensoriais demonstraram que as bebidas apresentaram boa aceitação. No entanto, a bebida produzida com soro permeado de ultrafiltração obteve maior aceitação e foi preferida em relação às demais. Ao longo do tempo de estocagem as bebidas apresentaram a mesma aceitabilidade sensorial. A bebida láctea desenvolvida pode agregar valor ao soro desproteinado permitindo o seu uso adequado e sustentável por parte das indústrias de laticínios. / The purpose of this study was to offer new alternatives for the sustainable use of unprocessed whey through the development and availability of simple technologies for the production of acidified carbonated dairy drinks with an extended shelf life without the use of extreme heat treatments. Three different types of deproteinated sera (ultrafiltration permeate, ricotta whey and acid whey obtained from the manufacture of cheeses coagulated by direct acidification) were used, which are normally discarded by the dairy industry. For each type of serum, acidified carbonated beverages were produced in 3 replicates that were analyzed over the 60 day period. There were significant differences between the beverages in relation to acidity, pH and viscosity. However, for each beverage, there were no significant differences in time, which means that they remained stable under these aspects during the 60 days of storage. However, protein deposition occurred between 20 and 30 days of storage due to the low pH and the loss of capacity of the stabilizer to keep these proteins in solution. The products presented microbiological stability during the whole storage time under refrigeration, not counting pathogenic microorganisms, thus confirming the effectiveness of the applied microbiological barriers (pH, heat treatment and carbon dioxide). Sensory analysis showed that the drinks were well accepted. However, the beverage produced with permeated ultrafiltration serum obtained greater acceptance and was preferred over the others. Throughout the time of storage the drinks presented the same sensorial acceptability. The developed dairy beverage can add value to the unprotected whey allowing its proper and sustainable use by the dairy industries.
363

Micellar-enhanced ultrafiltration for the removal of heavy metals from phosphorous-rich wastewaters:from end-of-pipe to clean technology

Landaburu-Aguirre, J. (Junkal) 25 September 2012 (has links)
Abstract Fertilizer industry often generates phosphorous rich wastewaters containing heavy metals. While phosphorous is a valuable compound for the industry, heavy metals hinder the recovery of phosphorous due to their detrimental effects on human health and the environment. Consequently, heavy metals must be removed from the wastewaters. In this study the use of micellar-enhanced ultrafiltration (MEUF) was evaluated for the removal of cadmium, copper, zinc and nickel from phosphorous rich wastewaters. This study has been conducted following a systematic methodology from single metal synthetic wastewaters to more complex synthetic and real wastewaters. The experimental work was conducted in a laboratory scale stirred cell using 3, 5 and 10 kDa regenerated cellulose membranes and in a cross flow semi-pilot scale equipment using a 10 kDa spiral wound polyethersulphone membrane. Statistical design of experiments was used as the research methodology to evaluate the effect of factors on the MEUF process performance as well as for finding optimal conditions. The factors studied were heavy metal, phosphorous and surfactant feed concentrations, pH, membrane nominal molecular weight limits, transmembrane pressure and cross flow velocity. The membrane performance was characterized by the heavy metal retention/rejection coefficients and the permeate flux. The experimental results showed that the removal of heavy metals from single synthetic wastewaters by MEUF is more efficient for more diluted systems. In complex systems containing phosphorous, simultaneous removal of heavy metals was successfully achieved obtaining rejection coefficients up to 80%. Phosphorous was not retained by the membrane showing the potential applicability of MEUF to purify phosphorous rich wastewaters. The study of metal complex formation and heavy metal competition has been shown to be very important in order to predict the MEUF results. Concentration polarization phenomenon was insignificant in the synthetic wastewaters but it was more severe when applying MEUF to real wastewaters. In addition, with real wastewaters SDS leakage was insignificant. This study has provided new and valuable knowledge regarding the applicability of MEUF to industrial wastewater treatment. / Tiivistelmä Lannoiteteollisuus tuottaa usein jätevesiä, jotka sisältävät huomattavia määriä fosforia, sekä pieniä määriä raskasmetalleja. Vaikka fosfori on tärkeä raaka-aine lannoiteteollisuudelle, jätevesissä olevat raskasmetallit kuitenkin estävät sen hyötykäyttöä fosforin lähteenä. Raskasmetallit ovat haitallisia sekä luonnolle että ihmisten terveydelle, joten niiden erottaminen jätevesistä on tärkeää. Tässä työssä tutkittiin miselliavusteisen ultrasuodatuksen (MEUF) käyttöä kadmiumin, kuparin, sinkin ja nikkelin poistamiseen fosforipitoisista jätevesistä. Väitöskirjatyössä tutkittiin systemaattisesti synteettisiä jätevesiä, jotka sisälsivät joko yhtä tai useita raskasmetalleja, sekä lannoitetehtaalta kerättyjä jätevesiä. Kokeet tehtiin laboratoriomittakaavan sekoituskennolla, jossa käytettiin 3, 5 ja 10 kDa:n regeneroituja selluloosakalvoja, sekä semi-pilot -mittakaavan spiraalielementillä, jonka materiaalina oli 10 kDa:n polyeetterisulfonikalvo. Väitöskirjatyössä hyödynnettiin tilastollista koesuunnittelua, jonka avulla arvioitiin muuttujien vaikutuksia MEUF-prosessin käyttäytymiseen. Koesuunnittelua hyödynnettiin myös optimiolosuhteiden määrittelemisessä. Koesuunnitelmien muuttujina olivat raskasmetallien, fosforin ja pinta-aktiivisen aineen pitoisuudet, pH, suodatuskalvojen katkaisukoot, paine sekä ristikkäisvirtauksen nopeus. Kalvon käyttäytymistä arvioitiin raskasmetallien erotustehokkuuden ja permeaattivuon avulla. Koetulokset osoittivat raskasmetallien erotuksen olevan tehokkainta synteettisistä, yhtä metallia sisältävistä jätevesistä, joiden raskasmetallipitoisuus oli pieni. Fosforia sisältävistä monimetalliliuoksista saavutettiin 80 %:inen raskametallien poistotehokkuus. Kalvoerotuksessa fosforipitoisuus ei muuttunut merkittävästi, mikä osoittaa MEUF:n olevan potentiaalinen menetelmä raskasmetallien poistamiseen fosforipitoisista jätevesistä. Metallikompleksien muodostumisen ja raskasmetallien välisen kilpailun ymmärtäminen osoittautuivat erittäin tärkeiksi MEUF-tuloksien ennustamisessa. Konsentraatiopolarisaatioilmiö ei ollut merkittävä käsiteltäessä synteettisiä jätevesiä, mutta teollisten jätevesien käsittelyssä ilmiöllä oli huomattava vaikutus permeaattivuohon. Kuitenkin teollisen jätevesien käsittelyssä SDS:n vuotaminen kalvon läpi oli merkityksetöntä. Tämä tutkimus on antanut uutta ja merkittävää tietoa MEUF:n soveltuvuudesta teollisten jätevesien käsittelyn.
364

Hybrid membrane processes in industrial water treatment:separation and recovery of inorganic compounds

Juholin, P. (Piia) 29 November 2016 (has links)
Abstract Industrial wastewaters are complex waters, which can contain a large variety of compounds such as heavy metals and salts as well as nutrients, e.g. nitrogen compounds and phosphorous. Prevention of wastewater formation is not always possible and therefore new more efficient water treatment techniques are needed. Legislation also supports the use of more efficient water treatment techniques, which can lead to better purification results and the recovery of valuable compounds from wastewaters. One technique, which has been of interest, is membrane technology. Membrane technology can separate heavy metals, salts and nutrients effectively, also at low concentrations, which is not always possible with conventional water treatment methods. The main disadvantage of membrane technologies is membrane fouling, which reduces the membrane permeate flux and separation efficiency. In this thesis membrane techniques were combined into hybrid processes to increase the efficiency of water treatment to reduce fouling and to widen the application areas of membrane technologies, as well as to increase the awareness of the benefits gained when using hybrid membrane processes in wastewater treatment. Three different hybrid membrane processes were applied. Catalytically active nanofiltration membranes were used to purify real mine wastewaters from harmful compounds, including sulphate. A catalytic layer reduced the membrane fouling tendency. Micellar-enhanced ultrafiltration was applied successfully to the separation of heavy metals from phosphorous-rich wastewater of a fertilizer company to achieve selective separation. In addition, reverse osmosis and membrane distillation were applied to the concentration of heavy metals, a metalloid and nitrogen compounds containing synthetic wastewater efficiently. High volume concentration factor was achieved with the RO-MD process. In this thesis high heavy metal, metalloid, and salt removal efficiencies were achieved with all hybrid membrane techniques. Hybrid membrane techniques were also categorized based on their properties. The study provides new knowledge on hybrid membrane techniques in the removal of inorganic compounds from industrial waters. / Tiivistelmä Teollisuuden jätevedet voivat sisältää kohonneita haitta-ainepitoisuuksia, kuten raskasmetalleja ja suoloja. Teollisuuden jätevedet voivat sisältää myös ravinteita, esimerkiksi typen yhdisteitä ja fosforia. Jätevesien syntymistä ei aina voida ennaltaehkäistä, ja siksi uusille entistä tehokkaammille vedenkäsittelymenetelmille on tarvetta. Lisäksi myös lainsäädäntö vaatii entistä tehokkaampaa vesien puhdistusta, mikä osaltaan edistää entistä tehokkaampien puhdistustekniikoiden kehitystä sekä erotettujen aineiden talteenottoa. Yksi aktiivisen tutkimuksen kohteena oleva vesienkäsittelyssä käytetty menetelmä on kalvoerotustekniikka. Kalvoerotustekniikoilla voidaan erottaa tehokkaasti raskasmetalli-ioneja, sulfaattia ja ravinteita, kuten typpiyhdisteitä teollisuuden jätevesistä myös alhaisissa pitoisuuksissa, missä yleisesti käytettävät menetelmät voivat olla tehottomia. Yksi kalvoerotusmenetelmien ongelma on kalvojen likaantuminen, mikä alentaa kalvojen erotustehokkuutta ja vähentää tuottavuutta. Tässä tutkimuksessa kalvojen likaantumistaipumista on vähennetty yhdistämällä kalvoerotustekniikoita muihin erotusmenetelmiin hybriditekniikoiksi. Tässä työssä on tutkittu kolmea eri hybridimenetelmää. Sinkkioksidilla pinnoitettuja nanosuodatuskalvoja tutkittiin ja verrattiin kaupallisiin nanosuodatuskalvoihin kaivosteollisuuden vesien puhdistuksessa mm. sulfaatista. Katalyyttipinnoite muutti kalvoja vähemmän likaantuviksi, ja näin menetelmän tehokkuus parani. Miselliavusteisella ultrasuodatuksella erotettiin fosforipitoisesta lannoitetehtaan jätevedestä raskasmetalleja selektiivisesti, ja näin mahdollistettiin fosforin uudelleenkäyttö. Kolmannessa tutkimuskohteessa konsentroitiin kalvotislauksen ja käänteisosmoosin yhdistelmällä raskasmetalli- ja typpiyhdisteitä sisältävää synteettistä jätevettä pieneen tilavuuteen. Työssä saavutettiin korkeita raskasmetallien ja suolojen erotustehokkuuksia kaikilla käytetyillä tekniikoilla. Työssä arvioitiin myös yhteenvetona erilaisten hybridimembraanitekniikoiden eroja ja ominaisuuksia ja tekniikoita jaoteltiin menetelmien ominaisuuksien mukaan. Työ antoi uutta tietoa hybridimembraanitekniikoista epäorgaanisten aineiden erotuksessa teollisuuden vesistä.
365

Treatment and characterisation of oily wastewaters

Karhu, M. (Mirjam) 18 August 2015 (has links)
Abstract Oily wastewaters are heterogeneous, containing various types of oils, surfactants from detergents, metals etc. Oily wastewaters are produced from a wide range of industries such as metalworking, petroleum refineries, the petrochemical industry, transportation as well as the textile and food industries. Oily wastewaters, especially those containing stable oil-in-water emulsions, require advanced treatment as conventional treatment methods have their limitations to meet ever-stricter environmental regulations. Ultrafiltration is a widely accepted and commonly used treatment method for oily wastewaters. The first aim of this thesis was to increase knowledge concerning the performance of an industrial-scaled ultrafiltration-based process treating concentrated real oily wastewaters. The demand for a more effective pre-treatment method for ultrafiltration to enhance performance and decrease fouling of membrane was observed. The second aim of the thesis was to investigate the suitability and efficiency of different methods for treating concentrated model oil-in-water emulsions and real oily wastewaters. The treatment methods studied were electrocoagulation (electrolytic dissolution of anodic metal), conventional coagulation-flocculation followed by either sedimentation or dissolved air flotation, and dissolved air flotation utilising cationic air bubbles. Electrocoagulation was discovered to be a promising treatment method for various types of oil-in-water emulsions. Dissolved air flotation with cationic modified air bubbles was proven to be an efficient method with even higher treatment results with smaller chemical doses when compared to conventional coagulation-flocculation followed by dissolved air flotation. The biodegradation of various components is an important measure of their impact on the environment in case of spillage. The third aim of the thesis was to explore the biodegradability of different types of oils and surfactants in solution conditions and soils. It was discovered that the biodegradation of light fuel oil continued during a three-month time period, reaching a biodegradation degree of over 60% in mineral-rich soil. For surfactants, their distinct effect on the biodegradation of organic material in soil was observed, and it masked the biodegradation of the surfactants themselves. / Tiivistelmä Öljyiset jätevedet ovat heterogeenisiä, sisältäen mm. erityyppisiä öljyjä, metalleja ja pesuaineiden pinta-aktiivisia aineita. Öljyisiä jätevesiä muodostuu laajalti eri teollisuuksista, kuten metallintyöstöstä, öljyn jalostuksesta, petrokemian teollisuudesta, ruoka- ja tekstiiliteollisuudesta sekä liikenteestä. Öljyiset jätevedet, varsinkin stabiileja öljyemulsioita sisältävät, vaativat tehokkaan käsittelymenetelmän, jotta ympäristölainsäädännön ja luvituksen ehdot täyttyvät. Ultrasuodatus on yleisesti käytössä oleva öljyisten jätevesien käsittelymenetelmä. Tämän väitöstyön ensimmäinen tavoite oli lisätä tietoutta teollisen mittakaavan konsentroituneiden öljyisten jätevesien ultrasuodatusprosessien tehokkuudesta. Prosessien strategisista kohdista kerättyjen öljyisten jätevesien karakterisointitulosten perusteella havaittiin, että ennen ultrasuodatusta tarvitaan tehokas esikäsittelyvaihe prosessin tehostamiseksi ja ultrasuodattimen tukkeutumisen vähentämiseksi. Täten toinen väitöstyön tavoite oli selvittää eri menetelmien soveltuvuutta ja tehokkuutta konsentroituneiden malliaineina käytettyjen öljyemulsioiden ja öljyisten jätevesien käsittelyssä. Tutkitut käsittelymenetelmät olivat elektrokoagulaatio (sähkökemiallinen flokkaavien metalli-ionien liuottaminen anodilta), koagulaatio-flokkulaatio ja laskeutus/korkeapaineflotaatio sekä korkeapaineflotaatiomenetelmä, joka hyödyntää kationisia ilmakuplia. Elektrokoagulaation todettiin olevan erittäin tehokas käsittelymenetelmä, jolla saavutettiin korkeat puhdistustulokset erityyppisille öljyemulsioille. Korkeapaineflotaatiolla, joka hyödyntää kationisia ilmakuplia, saavutettiin hyvät puhdistustulokset jopa pienemmillä kemikaalimäärillä verrattuna perinteiseen koagulaatio-flokkulaatioon ja korkepaineflotaation. Erilaisten komponenttien biohajoavuus on tärkeä suure arvioitaessa niiden ympäristövaikutuksia. Väitöstyön kolmas tavoite oli selvittää erilaisten öljyjen ja pinta-aktiivisten aineiden biohajoavuutta erilaisissa liuosolosuhteissa ja maa-aineksissa. Tärkeimmät biohajoavuustutkimustulokset olivat, että kevyt polttoöljy saavutti kolmen kuukauden mittauksen aikana yli 60 % biohajoavuusasteen mineraalirikkaassa maa-aineksessa. Pinta-aktiivisten aineiden havaittiin lisäävän huomattavasti maan orgaanisen aineksen biohajoamista, ja tämä vaikeutti itse pinta-aktiivisten aineiden biohajoamisen arviointia.
366

The effect of natural organic matter on ultrafiltration and reverse osmosis membrane performance at Komati Power Station

Dladla, Zanele January 2013 (has links)
Komati Power Station has installed a membrane plant consisting of ultrafiltration, double pass reverse osmosis and continuous electro-deionisation to treat cooling tower blowdowns in order to produce demineralised water and to conduct sidestream chemistry control of the cooling water circuit. This plant has replaced the existing ion-exchange plant that was used for the production of demineralised water and thus serves to reduce the loading of mobile salts in the ash dam (90% reduction) by eliminating regeneration effluent from the ion-exchange plant. Due to oil contamination in the cooling water circuit (when oil from oil coolers leaks into the cooling water), the membrane plant was also designed to operate on raw water from either the Nooigdedacht or the Vygeboom Dam or a blend of both dams. This is considered to be an emergency intervention under abnormal conditions to prevent possible irreversible fouling of the membranes due to oil in the cooling water. The Nooigtedach Dam water contains high concentrations of organic matter and is also enriched with nutrients due to raw sewage influent into the Dam water. This poses a challenge with regard to treatment of the high fouling feed water on the membrane plant. Natural organic matter in water has the ability to foul reverse osmosis membranes. This adversely affects the operation of the reverse osmosis process. However, very little information is available regarding the fouling characteristics of natural organic material in the raw and cooling water at Komati Power Station for the reverse osmosis membranes. Therefore, a pilot study was undertaken to determine the influence of natural organic matter on membrane fouling, to optimise the process for the removal of natural organic matter and to assess the ability of two different reverse osmosis membranes to effectively treat the high fouling feed water at Komati Power Station. The ability of a polyethersulphone hollow-fibre ultrafiltration membrane system was first evaluated to remove natural organic matter in the feedwater, by conducting pilot tests, initially without coagulation of the raw water and thereafter with in-line coagulation for organics removal. Jar tests were conducted in the laboratory to determine the most suitable coagulant and dosage for turbidity and natural organic matter removal. Various coagulants were tested and, based on the results of the jar tests, a coagulant (U3000) was identified based on optimal removal of both total organic carbon and turbidity at a dosing level of 20 mg/L. During the operation of the ultrafiltration pilot plant, permeate flow; feed pressure and feed temperature were monitored. Performance of the ultrafiltration membrane was monitored in terms of flux versus time for operation with and without a coagulation process. The results indicated that there was very little total organic carbon removal (maximum removal of 4%) without coagulation and a slight decrease in flux. The flux declined as a result of fouling but could be recovered by performing hydraulic backwashes and CEB procedures. Permeate flux, however, could be maintained at about 90 Lmh (from 642 hours of operation). Since most of the organics passed through the ultrafiltration membrane, it was concluded that the loss in flux was due to colloidal fouling of the membrane. This was observed when the operation was carried out using raw water as feed as well as when cooling water was used. The total organic carbon removal increased to 30% when the plant was operated with inline coagulation. The flux remained relatively stable during the first 600 hours of operation and only decreased significantly during the last 200 hours of operation as a result of fouling. The reduction in flux prior to cleaning was less than the 15% (maximum flux decline of 9.9% during the test period) which is acceptable according to the industry norm of 15%. It appeared that flux could be maintained at around 90 Lmh which was about the same as when no coagulant was applied. The 30% total organic carbon reduction that was obtained was not sufficient to reduce the organics to the level of 6mg/L dissolved organic carbon that was specified by the membrane manufacturer for the standard brackish water reverse osmosis membrane. Two reverse osmosis membranes – the standard brackish water reverse osmosis membrane (BW30-2540) and the extra-low-fouling membrane (BW30XFR-2540) – were assessed in terms of their ability to remove dissolved organic carbon, ease of cleaning of the membrane and the ability to recover flux after cleaning. This was done to establish which membrane is more suited to Komati’s high-fouling feedwater. The evaluation of the performance of the two reverse osmosis membranes was conducted using pre-treated water (filtered water after in-line coagulation, anti-scalant and biocide dosing) as well as using water that was not pre-treated. During operation (under both conditions), the normalised permeate flux, conductivity, dissolved organic carbon and organics absorbing at UV254 were monitored. It was established that in terms of flux decline that the extra low-fouling membrane gave slightly superior performance to that of the standard membrane, achieving longer production runs (up to 5 days compared with 3 days achieved by the standard brackish water membrane) without requiring chemical cleaning. The low fouling membrane achieved better CWF recovery after the cleaning cycles (81.26% Lmh of the virgin membrane on the occasions when there was flux loss) compared to the standard membrane (restored to 77.35% of CWF of the virgin membrane) when using untreated feed water. This performance improved when pre-treated feed water was used and the low fouling membrane’s CWF regained after the CIP was 95.89% which was within the industry norm of a flux recovery of 95%, indicating that the CIP had been effective. It was determined that the TOC rejection of the low-fouling membrane was higher (average TOC rejection of 97%, maximum TOC rejection of 99%) than that of the standard membrane (average TOC rejection of 95.3%, maximum TOC rejection of 97%). Preliminary efforts to optimize the pre-treatment for organics removal in order to reduce organic loading for the RO membranes confirmed that the use of granular activated carbon and use of an organic scavenger resin might not be economically feasible due to the relatively quick TOC breakthrough (8910BV, approximately 18000BV and less than 18000BV for the Filtrasorb 300, Filtrasorb 400 and organic scavenger resin, respectively). Although further investigations should still be conducted, the preliminary results indicate that it would be beneficial to also identify other options that can be further investigated for optimization of organics removal at Komati Power Station. Decline in the normalised flux as well as the evidence of biofouling were witnessed during the pilot operation suggesting that the membranes were fouled. Autopsies were performed on both membranes to identify foulants responsible for the decline in flux that was observed during the pilot study. The results did not indicate an organic foulant on the membrane surface. Biofouling should however, be monitored in the main plant as this was suspected to have resulted in the flux decline during the pilot study. The low fouling membrane demonstrated a better capability to treat the Komati raw and cooling water and would be expected to achieve lower operating costs for the plant (CIP costs and membrane replacement costs) while achieving better organics removal and it is therefore recommended that the low-fouling membranes be used at Komati Power Station as they are superior to the standard membrane and the cost of the low-fouling membranes is comparable to that of the standard membrane. While this would provide somewhat better performance than that obtained with the standard brackish water membranes, it is proposed that further investigation into pre-treatment optimization for organics removal as well as more efficient cleaning solutions be investigated to improve the performance and economics of the main water treatment plant at Komati power Station. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Chemical Engineering / unrestricted
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Métodos alternativos de purificação do polissacarídeo capsular de Haemophilus influenzae tipo b. / Alternative methods for purification of capsular polysaccharide produced by Haemophilus influenzae type b.

Silvia Maria Ferreira Albani 02 February 2009 (has links)
Haemophilus influenzae tipo b é uma bactéria Gram-negativa, patogênica causadora de meningites em crianças. A cápsula polissacarídica (PSb) é o principal fator de virulência e é usado como antígeno vacinal. O método clássico de purificação do PSb envolve várias etapas de precipitação com etanol, fenol e detergente catiônico (inflamável, corrosivo e tóxico), e etapas de ultracentrifugação. O objetivo deste estudo foi substituir total ou parcial as precipitações e/ou uso das centrífugas por cromatografia, digestão enzimática, microfiltração e ultrafiltração tangencial. As cromatografias de troca iônica e de filtração em gel não apresentaram boas purificações, entretanto a hidrofóbica pode eliminar as proteínas contaminantes. As precipitações com etanol foram necessárias para obter a pureza requerida. O etanol de alguma forma favoreceu a ação enzimática e facilitou a posterior ultrafiltração. A separação com etanol em fibra-oca de microfiltração tangencial mostrou melhores purificações do que a centrifugação, mas com uso repetido verificou-se redução na eficiência. / Haemophilus influenzae type b is Gram-negative pathogenic bacterium cause meningitis in children. The capsular polysaccharide (PSb) is the main virulence factor and it is used as vaccine antigen. The classical PSb purification process includes ethanol, phenol and cationic detergent precipitations (explosion prone, corrosive, toxic) and ultracentrifugation steps. The aim of this work was to replace total or partial ethanol precipitations steps and/or elimination of centrifugation by chromatography methods, enzymatic digestion and ultrafiltration (UF) or microfiltration. The results have showed that ion exchange chromatography and gel filtration did not result in good purification, however the hydrophobic can be used for proteins elimination. The ethanol precipitation steps are necessary to achieve the required purity of PSb. In some way ethanol contributed for enzymes action and further improvements in the UF. The ethanol separation with hollow fiber microfiltration exhibited better purification than centrifugation, but after some uses the efficiency has reduced.
368

Posouzení základních ukazatelů odpadní vody firmy Dermacol / Assesment of basic characteristics of waste water from the Dermacol Company

Fribertová, Marcela January 2010 (has links)
This master thesis is focused on waste waters from cosmetics industry and basic indicators of these waters. The pollution of the environment caused by increase industrial development has a negative effect on ecosystem. Waste waters are part of the pollution. In theoretical part a basic indicators of waters (its definition and way of determination) have been described. Membrane processes for water purification have been mentioned as well – particularly the ultrafiltration. The experimental part of thesis deals with practical determination of indicators mentioned in methods described in the theoretical part. Results are discussed at the close. The discussion is focused on evaluation of efficiency of the device for waste waters adjustment, which is in use in the Dermacol company, which produces cosmetics products.
369

Primena ultrafiltracije genetski modifikovanog himozina i proteolitičkih enzima u tehnološkom procesu proizvodnje kačkavalja / APPLICATION OF ULTRAFILTRATION, GENETICALLYMODIFIED CHYMOSIN AND PROTEOLYTIC ENZYMES IN KASHKAVAL CHEESE MANUFACTURE

Milanović Spasenija 12 November 1993 (has links)
<p><strong>Apstrakt je obrađen tehnologijama za optičko prepoznavanje teksta (OCR).</strong></p><p>Imajući u vidu naučni i praktičan značaj i nedostatak podataka o aplikaciji ultrafiltracije (UF), alternativnih koaguli&scaron;ućih enzima, posebno genetskog himozina, kao i enzima za akceleraciju zrenja u tehnologiji tvrdih sireva, za predmetna istraživanja je odabran Kačkavalj, popularni sir mediteranskog porekla.<br />U okviru istraživanja je u industrijskim uslovima izvr&scaron;ena proizvodnja KačkavaIja iz retentata dobijenog nakon ultrafiltracije mleka po LCR (Low Concentrated Retentate) postupku (UF Kačkavalj). Ispitan je uticaj koagulanasa mikrobiolo&scaron;kog porekla (M. miehei proteaza, Rennilase) i genetski modifikovanog himozina (Maxiren) na kvalitet finalnog sira i upoređen sa klasičnim analozima (kontrolni Kačkavalj). Istražena je mogućnost skraćenja perioda zrenja obe varijante Kačkavalja (klasični i UF) dodatkom &bdquo;koktela&quot; enzima za ubrzanje zrenja proteolitičkog (Accelase) i lipolitičkog (Paletase) dejstva.<br />Na osnovu rezultata dobijenih ispitivanjem fizičko-hemijskog sastava, mikro-strukture i senzornog kvaliteta varijanti konvencionalnog Kačkavalja i UF analoga tokom jednogodi&scaron;njeg zrenja, utvrđeno je da se dejstvo rekombinovanog himozina (Maxiren-a) i standardnog himozina signifikantno ne razlikuje, potvrđujući dosada&scaron;nja saznanja da je genetski modifikovani himozin potpuno kompetentan proteolitički agens za koagulaciju mleka u procesu proizvodnje sira. Kod konvencionalnog i UF Kačkavalja proizvedenog primenom mikrobiolo&scaron;ke M. miehei proteaze (Rennilase) ustanovljena je najniža koncentracija mlečne masti u suvoj materiji tokom celokupnog ispitivanog perioda, &scaron;to se sa ekonomskog aspekta negativno odražava na kvalitet sira. Sve varijante UF Kačkavalja se tokom zrenja razlikuju od klasičnih analoga po hemijskom sastavu (sadržaj mlečne masti, ukupnog N, NPN, RN itd.), profilu proteolitičke degradacije as- i p-kazeina, modelu distribucije identifikovanih is- parljivih komponenata arome, reolo&scaron;kim i senzornim karakteristikama i mikrostrukturi usled<br />usporenog intenziteta promena proteinske i lipidne faze UF sireva tokom zrenja. Efekat ubrzanja zrenja Kačkavalja tretiranog &bdquo;koktelom&quot; enzima lipolitičkog i proteolitičkog dejstva je izraženiji kod konvencionalnog nego UF uzorka.</p> / <p><strong>Abstract was processed by technology for Optical character recognition (OCR).</strong></p><p>The scientific and practical significance and the lack of literature data on the<br />application of ultrafiltration (UF), as well as the alternative coagulating enzymes, particularly genetic chymosin, and enzymes for accelerated ripening in hard cheese technology were essential reasons for choosing this field for research. The object of presented investigations was Kashkaval, the popular mediterranean hard variety cheese.<br />In the scope of these investigations, Kashkaval was industrially produced using retentate obtained by UF of milk according to LCR (Low Concentrated Retentate) procedure (UF Kashkaval). Effects of clotting enzymes of microbiological origine (M. miehei protease, Rennilase) and of genetically modified chymosin (Maxiren) on the quality of final cheese product was also investigated and compared to conventional analogues (control Kashkaval). The possibility for reduced ripening period of both Kashkaval types (traditional and UF) was investigated by the addition of &bdquo;coctail&quot; of enzymes which accelerate the cheese ripening, involving the proteolytic (Accelase) and lypolytic (Palatase) activity.<br />According to the results obtained by the investigations of physico-chemical composition, microstructure and sensory quality of conventional Kashkaval and UF analogues in the course of one-year ripening period, it was possible to derive the conclusion that the effects of recombined chymosin (Maxiren) and the standard one are insignificantly different, confirming thus the former knowledge that the genetically modified chymosin is an adequate proteolytic agent for milk coagulation in cheese production. The lowest level of milk fat in dry matter over the whole investigated period was established both for conventional and UF Kashkaval samples produced by the application of M. miehei protease (Rennilase), whereas from the economic standpoint this indicated negative effects on cheese quality. All UF Kashkaval varieties differ during the period of ripening from conventional analogues concerning chemical composition (content of milk fat, total N, NPN, RN etc.), profile of proteolytic degradation of as- and p-casein, distribution of identified volatile aroma<br />components, rheological and sensory characteristics as well as the microstructure due to the slower intensity of changes in protein and lipid phases of UF cheese samples during ripening. The &bdquo;cocktail&quot; of proteolytic and lipolytic enzymes showed more pronounced effects on the Kashkaval ripening in the case of conventionally produced cheese sample.</p>
370

Aplikace membránových technologií pro výrobu pitné vody z odtoku z ČOV / Application of membrane technologies for the production of drinking water from the effluent from the WWTP

Minich, Marek January 2021 (has links)
The Master’s Thesis deals with the application of membrane technologies in the production of drinking water from the effluent of a municipal wastewater treatment plant (WWTP). There were two types of pressure-driven membrane processes selected – ultrafiltration and reverse osmosis, to achieve water production of the required quality. For the needs of the diploma thesis, an already existing pilot-scale membrane unit of the ASIO TECH Company l.t.d. was used. There were 44 physical, chemical and microbiological parameters observed to assess the quality of the produced water and also the input water (effluent from the WWTP). None of the afore mentioned parameters exceeded the limit values, more specifically the highest limit values issued by the Decree 70/2018 Coll. However, the produced water cannot be considered as drinking water because of its low mineralisation. Before its potential application in practise, it is therefore necessary to choose an appropriate method of remineralisation as well as to follow all the other legislative requirements for the drinking water, which have already been out of the scope within the Master’s Thesis.

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