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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.
221

Spatial distribution of heavy metals in Center Township, Delaware County surface soils

Liberti, Michael F. January 1998 (has links)
Numerous urban soils surrounding industrial and metallurgical facilities in the U.S. are contaminated with metals including lead (Pb), cadmium (Cd), copper (Cu), Zinc (Zn), chromium (Cr), and nickel (Ni). Simplified geochemical mapping requires soil sampling and analysis for the presence of heavy metals from a grid pattern within a geographic area. In this study, a contour map of metal concentrations at two depths was subsequently superimposed over a standard political map to indicate areas of elevated metal concentrations in the soil. Natural levels of Pb, Cd, Cu, Zn, Cr, and Ni in Delaware County soils were determined to be 114.2 mg/kg, 0.14 mg/kg, 29.3 mg/kg, 88.4 mg/kg, 9.0 mg/kg, and 39.8 mg/kg, respectively. The average concentrations of metals found throughout Muncie, 203.9 mg/kg Pb, 39.2 mg/kg Cu, 275.4 mg/kg Zn, 9.7 mg/kg Cr, and 25.0 mg/kg Ni, were compared with natural levels to determine the extent of heavy metal pollution from atmospheric deposition. From the geographic mapping of metal concentrations, the effect of past industrial processes on possible contamination of soils by metals in Muncie, Indiana, was determined. Metals were also be fractionated in order to assess the percentage which is potentially bioavailable. / Department of Natural Resources and Environmental Management
222

Responses of wild freshwater fish to anthropogenic stressors in the Waikato River of New Zealand

West, D. W. January 2007 (has links)
Thesis (Ph.D.)--University of Waikato, 2007. / Title from PDF cover (viewed March 19, 2008) Includes bibliographical references (p. 99-118)
223

Effect of copper and nickel on the performance of an activated sludge system treating cellulose acetate wastewater /

Sadagopan, Rishi S., January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 131-139). Also available via the Internet.
224

Management, disposal and recycling of waste organic solvents in Hong Kong /

Lau, Kin-wah. January 1998 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 106-111).
225

Optimisation of propionibacterial ECP production and the influence of propionibacteria on the UASB granulation process

Joubert, Hannarine 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: The "classical" propionibacteria are used in a variety of natural dairy fermentations where they produce natural preservatives (propionic and acetic acids and bacteriocins) and large amounts of vitamin B12. The extracellular polysaccharide (ECP) producing ability of these bacteria also make them of special interest to the food and waste water management industries as the ECP has been illustrated to playa role in the initial granule formation in upflow anaerobic bioreactor systems. There is little known on the ECP production by propionibacteria and in this study different environmental conditions that influence ECP production were studied. Nineteen different Propionibacterium strains were examined in terms of ECP production and Propionibacterium strain 278 was identified as the best ECP producer. Further studies were only done on this strain because of its high ECP production and because it was originally isolated from an anaerobic digester. The influence of temperature, pH and sucrose concentration was determined through the measurement of ECP production and medium viscosity. It was found that more ECP was produced at temperatures lower than the optimum for growth with the optimum being between 22° and 25°C. Lower initial pH conditions of the growth medium (below pH 7.0) were found to inhibit ECP production and the influence when the initial pH values were between 7.0 and 8.5, was not significant. A higher carbon: nitrogen ratio, when 8% sucrose was added, was also found to enhance the ECP production. The upflow anaerobic sludge bed (UASB) bioreactor process depends on the upward movement of soluble matter through a blanket of active methanogenic granular sludge. The long start-up times as a result of the slow granulation process, as well as the need for a speedy replacement of granules once they have been washed out of the system, are limitations that restrict the general application of this excellent waste water treatment technology. Full exploitation of this biomass immobilisation technique can thus not be realised until the granule formation conditions are defined and optimised. The precise nature of the mechanisms involved in the formation of granules and the reason for their stability, is still not fully understood. It was hypothised by Britz et al. in 1999 that, through the implementation of environmental 'stress' conditions, a shift in the population dynamics of the anaerobic community can be obtained. This results in a concurrent increase in ECP formation that appears to enhance aggregate formation. In the second study it was found that, when 'stress' conditions were applied to already formed granules, the Gram-positive lactate-utilising acidogenic population gained an advantage and more propionic acid producing bacteria were present. The propionic and acetic acid concentrations were also found to increase, and concurrently, a decrease in the growth medium pH occurred. This confirms part of the granulation hypothesis that, when granules are 'stressed', the acidogenic population dynamics change and the lactate-utilising population responds to the gradual decrease in pH and the more acid-tolerant propionic acid producing bacteria gain a competitive advantage resulting in the increase in the propionic acid concentration. When propionibacteria were added to raw sludge during the granule production process, the granules were found to be more active than when nopropionibacteria had been added. This was probably due to the ECP formation by the propionibacteria that enhances the aggregation of the granules. Enhanced granulation was thus found in the batch systems with the fatty acids formed in correlation with the model for granulation. A good correlation was evident between the hypothesis and the experimental data and the hypothesis was partially verified in this study. / AFRIKAANSE OPSOMMING: Die "klassieke" propionibakterieë word in 'n verskeidenheid van natuurlike suiwel fermantasies gebruik waarin hulle verantwoordelik in vir die produksie van natuurlike voedsel preserveermiddels (propioonsuur, asynsuur en bakteriosiene) en groot hoeveelhede vitamiene B12. Die Ekstra Sellulêre Pollisakkaried (ESP) produserende eienskap van hierdie groep bakterieë maak hulle ook van belang in die voedsel en afvoerwater beheer industrieë, aangesien gevind is dat ESP 'n rol speel in die aanvanklike granule formasie in anaerobiese bioreaktor sisteme. Daar is nog baie min bekend oor die ESP produksie van propionibakterieë en in hierdie studie is verskeie omgewings faktore wat die ESP produksie beïnvloed, bestudeer. Negentien verskillende Propionibakterium stamme was bestudeer in terme van ESP produksie en Propionibakterium stam 278 was geïdentifiseer as die stam wat die meeste ESP produseer. Verdere studies was op hierdie stam gedoen na aanleiding van sy hoë ESP produksie en omdat dit oorspronklik uit 'n anaerobiese verteerder geisoleer is. Die invloed van termperatuur, pH en sukrose konsentrasie was bepaal deur die meting van die ESP produksie en die medium viskositeit. Dit was gevind dat meer ESP geproduseer was by temperature laer as die optimum vir groei, met die optimum temperatuur tussen 22° en 25°C. Dit is ook gevind dat laer aanvangs groei-medium pH (laer as pH 7.0), ESP produksie inhibeer. Die invloed van die aanvangs groei-medium pH tussen 7.0 en 8.5 was egter nie betekenisvol nie. Dit is ook gevind dat 'n hoër koolstof tot stikstof verhouding, verkry deur die byvoeging van 8% sukrose, die ESP produksie verhoog. Die "upflow anaerobic sludge blanket" (UASB) proses vind plaas as gevolg van die opwaarste beweging van opgeloste organiese materiaal deur 'n granule bed van aktiewe metanogeniese granulêre slyk. Die lang 'start-up' tye as gevolg van die stadige granulasie proses, en die nodigheid om 'n vinnige verplasing van granules te hê nadat dit uit die sisteem gewas is, is beperkings wat die algemene toepassing van hierdie fantastiese afvoerwater tegnologie, strem. Volle implementering van hierdie biomassa immobilisereings tegniek kan dus nie plaasvind voordat die granule formasie gedefinieer en geoptimiseer is nie. Die presiese eienskappe van die meganismes betrokke en die formasie van die granules en die rede vir hul stabiliteit word egter nog nie ten volle verstaan nie. Volgens 'n hipotese deur Britz et al. (1999), vind 'n verskuiwing in die populasie dinamika van die anaerobiese gemeenskap plaas tydens die implementasie van omgewings 'stress' toestande. Die resultaat is 'n verhoging in ESP produksie en 'n gevolglike verbetering in die granulasie proses. In die tweede studie was dit gevind dat, wanneer 'stress' toestande op die reeds gevormde granulasie toegepas word, die Gram-positiewe laktaat-benuttende asetogeniese populasie voordeel geniet en meer propioonsuur produserende bakterieë was teenwoordig. Die propioonsuur en asynsuur konsentrasies het ook verhoog en met 'n gevolglike daling in die groei-medium se pH. Dit bevestig 'n gedeelte van die hipotese dat, wanneer die granules onder 'stress' geplaas word, die asetogeniese populasie dinamika verander en die laktaat-benuttende populasie reageer tot die gedeeltelike afname in pH. Die meer suur-tolerante propioonsuur produserende bakterieë verkry 'n kompeterende voordeel en gevolglik is daar 'n verhoging in propioonsuur konsentrasie. Propionibakterieë was gevoeg by die onbehandelde slyk gedurende die granule produksie proses, en daar is gevind dat meer aktiewe granules gevorm word as andersins. Dit is moontlik as gevolg van die die ESP produksie van propionibakterieë wat die granulasie versnel het. Verbeterde granulasie was dus verkry in die sisteme waar propionibakterieë bygevoeg is. Vetsuur analises het gedui dat die gevormde vetsure ook in korrelasie was met die model van granulasie. Goeie korrelasie was dus verkry tussen die hipotese en die eksperimentele data en die hipotese is gedeeltelik bewys in hierdie studie.
226

Preservation techniques and carbon and nitrogen growth enhancement of batch cultivated UASB granules

Cameron, Michelle 12 1900 (has links)
Thesis (MSc Food Sc )--Stellenbosch University, 2000. / ENGLISH ABSTRACT: The potential use of the upflow anaerobic sludge blanket (UASB) bioreactor is limited by the extended start-up periods due to the time-consuming granulation process and the fact that seeding inoculum is not freely available in most developing countries like South Africa. The mass cultivation of granules would provide the waste water treatment industry with suitable seeding inoculum and, therefore, an efficient waste water treatment option would be more easily available. By applying 'stress' conditions on a bioreactor system seeded with raw anaerobic sludge, the population dynamics of the anaerobic community change and the acidogens start to produce extracellular polymers, which in turn enhance the granulation process by providing a matrix for the bacterial cells to adhere to. These "environmental stress" conditions include changes in the C:P:N ratio's. The aim of this study was, therefore, to assess the impact of different carbon and nitrogen sources on the enhancement of granulation in a batch system, and to determine the best preservation technique in terms of retainment of activity. It was found that the carbon source and concentration had a significant influence on batch granule enhancement. Low concentrations (2.g.l ̄ ¹) of glucose gave the best granule enhancement over a 14 day incubation period. Fruit cocktail effluent was found to be a cheap and effective carbon source for batch granule cultivation. It was found that different nitrogen sources did not have the same impact on granule enhancement, however, urea, at all concentrations tested, gave the best granule enhancement. A major problem encountered during the study was the standardisation of the inoculum. Significant granule enhancement comparisons between the different carbon sources were impeded by the lack of a suitable and reliable form of sludge standardisation. Future research needs to address this problem of the standardisation of the sludge inoculum as this would lead to more kinetically comparable results. Mass granule culturing will require granule preservation without risking the loss of activity. In the second study, six different preservation techniques and storage periods were evaluated in terms of the retainment of activity. These involved freeze-drying, vacuum freeze-drying, vacuum-drying, freezing, cold storage and room temperature preservation. Activity testing was used for comparing the efficiency of the different preservation techniques in terms of the tempo of biogas and methane production. Freeze-drying the granules, with storage for up to 90 days was found to give the best retainment of activity, followed by vacuum freeze-drying. The room temperature preserved samples showed a sudden increase in activity by day 120, which could possibly be explained by cell hydrolysis of the granules after day 90. The highest activity was achieved after 10 h of incubation, and it was, therefore, suggested that activity testing for evaluation purposes should use an incubation time of only 10 h. Furthermore, only the basic test medium with added glucose should be used for activity testing as it was observed that the addition of lactate and acetic acid played no decisive role in determining the level of activity of the granules. This study recommends the use of low concentrations of glucose for optimum granule enhancement during the mass cultivation of granules, and the addition of low concentrations of lactate to ensure a stable system with no acidification. It is also advisable to use a standardised sludge inoculum, as this will allow more efficient comparisons. Freeze-drying is recommended as preservationtechnique as this technique showed the best retainment of activity. A storage period of 90 days is, however, too short to be of much use for the industry. This will have to be investigated, together with the phenomenon of increased activity after 90 days as shown by the room temperature preserved granules. / AFRIKAANSE OPSOMMING: Die potensiële gebruik van die "uptflow anaerobic sludge blanket" (UASB) bioreaktor word beperk deur verlengde aansitprosedure as gevolg van die tydsame granulasieproses en die feit dat geskikte inokulums nie vrylik beskikbaar is in die meeste ontwikkelende lande, bv. Suid-Afrika nie. Die massa-kweking van granules sal die afvalwater-industrie voorsien van 'n geskikte inokulum, en sodoende 'n effektiewe opsie vir die behandeling van afvalwater beskikbaar stel. Deur die aanwending van "stres" toestande op 'n reaktor, wat geinokuleer is met rou anaerobe slyk, vind daar 'n verandering in die samestelling van die anaerobe populasie plaas. Die laktaat-benuttende asidogene begin om ekstrasellulêre polisakkariede te produseer wat die granulasieproses versnel deur 'n matriks te voorsien waaraan die bakteriële selle kan heg. Hierdie "omgewings stres" toestande sluit veranderinge in die C:P:N verhoudings in. Die doel van hierdie studie was om die invloed van verskillende koolstof- en stikstofbronne op die vermeerdering van granules te bepaal, asook om die beste preserveringstegniek in terme van die behoud van aktiwiteit te bepaal. Daar is gevind dat die koolstofbron en konsentrasie 'n betekenisvolle invloed op granule-vermeerdering het. Lae konsentrasies glukose (2 g.I ̄ ¹) het tot die grootste vermeerdering in granules oor 'n 14 dae inkubasieperiode gelei. Vrugtekelkie-afvalwater is geidentifiseer as 'n goedkoop en effektiewe koolstofbron wat ook gebruik kan word vir die kweking van granules. Voorts is gevind dat die stikstofbron en konsentrasie nie so 'n groot invloed op granule-vermeerdering het nie. Urea het nietemin die beste granule-vermeerdering vir al die konsentrasies wat getoets is, gegee. Standaardisasie van die inokulum was 'n groot probleem gedurende die studie. Betekenisvolle vergelykings tussen die granule-vermeerderings verkry met die verskeie groeimedia is bemoeilik deur die afwesigheid van 'n geskikte en betroubare standaardisasie-metode. Toekomstige navorsing moet hierdie probleem aanspreek aangesien dit sal lei tot meer kineties vergelykbare resultate. Massa-kweking van granule sal 'n metode van granule-preservering vereis sonder enige verlies van aktiwiteit. In die tweede studie is ses verskillende preserverings-tegnieke en opbergings-periodes in terme van die behoud van aktiwiteit geëvalueer. Die tegnieke sluit in: vriesdroging; vakuum-vriesdroging; vakuumdroging; bevriesing; koelopberging en kamertemperatuur-preservering. Aktiwiteitstoetsing is gebruik vir die vergelyking van die effektiwiteit tussen die verskillende preserverings-tegnieke in terme van die tempo van biogas- en metaanproduksie. Die granules wat met behulp van die vriesdroogtegniek gepreserveer is, het die beste behoud van aktiwiteit getoon, gevolg deur die vakuum-gevriesdroogde granules. Die monsters wat by kamertemperatuur gepreserveer is, het 'n skielike toename in aktiwiteit na 120 dae van opberging getoon en 'n moontlike verklaring vir hierdie verskynsel kan sel-hidrolise van die granules na 90 dae van opberging wees. Die meeste aktiwiteit is behaal na 'n 10 h inkubasietyd, en dus word hierdie inkubasietyd aanbeveel indien aktiwiteitstoetse vir evaluerings-doeleindes gedoen word. Verder word aanbeveel dat slegs die glukose-verrykte basiese toetsmedia vir aktiwiteitstoetsing gebruik word aangesien die byvoeging van laktaat en asynsuur geen noemenswaardige rol speel in die bepaling van die vlak van aktiwiteit van die granules nie. Hierdie studie beveel die gebruik van lae glukosekonsentrasies aan vir optimale vermeerdering van granules tydens die massakweking daarvan, asook die byvoeging van lae konsentrasies laktaat om 'n stabiele sisteem met geen versuring te verseker. Die gebruik van 'n gestandaardiseerde slyk-inokulum word sterk aanbeveel aangesien dit meer vergelykbare resultate lewer. Vriesdroging (as preserveringstegniek) het die beste behoud van aktiwiteit in die granules getoon en word dus as preserveringstegniek aanbeveel. 'n Opbergingsperiode van 90 dae is egter te kort om van veel waarde vir die industrie te wees. Hierdie probleem, asook die verskynsel van 'n verhoging in aktiwiteit na 90 dae van die granules wat by kamertemperatuur gepreserveer is, moet verder ondersoek word.
227

Extracellular polymer extraction and analysis from UASB granules and batch produced anaerobic granular sludge

Van Eeden, Alida Elizabeth 03 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: The start-up period of Upflow Anaerobic Sludge Bed (UASB) reactors can significantly be reduced by enhancing the time-consuming granulation process through the batch cultivation of anaerobic granular sludge and thus seeding the reactor with this cultivated granular sludge, instead of raw anaerobic sludge. The precise mechanism for granule formation is not well known, but it is believed that extracellular polymers (ECP) play a critical role in the granulation process. Information on the precise role of ECP is also limited and no universal standardised method for ECP extraction is used at present. Therefore, comparison of results from different researchers has to be made with great caution. The objectives of this study were to evaluate an ECP extraction methód so as to optimise the extraction time, and then to correlate ECP composition of UASB granules with granule metabolic activity. The impact of changes in the environmental conditions, such as sludge sources (Paarl and Kraaifontein-sludge), carbon growth substrates (yeast extract lactate, glucose medium and fruit cocktail effluent) and batch cultivation techniques (roller-table and shake-waterbath), on batch cultivation studies was also evaluated in terms of granule activity, ECP composition and granule formation. A physical extraction method was used to quantify the ECP content of UASB granules from six different sources. The optimal extraction time was taken as the time needed before cell lysis took place, and before intracellular material started contributing to the ECP content of the granules. It was concluded that the ECP composition was affected by the wastewater composition fed to the original UASB reactors, It was also found that the activity test results could be used to indirectly predict the activity of the different trophic groups present in the UASB granules. A correlation was found between the activity test results and the total ECP content, and this showed that the granules with the higher ECP yields exhibited greater biogas (SB) and methanogenic (SM) activities. However, based on the activity data and total ECP content, it appeared that a protein:carbohydrate ratio < 1 affected the activity of the granules, The sludge source used as inoculum for batch cultivation of anaerobic granular sludge had a significant effect on granule formation. The use of a pre- granulated raw anaerobic sludge, such as the Paarl-sludge, resulted in a greater increase in granule numbers at the end of the cultivation period. The acetic acid activity profiles showed that the acetoclastic methanogens that are involved in initiation of granulation by nucleus formation, were inactive or absent in the different batch systems, with the exception of the roller-table glucose cultivated Kraaifontein-sludge (RKG) batch system. The addition of glucose as carbon growth substrate for batch cultivation not only enhanced the activity of the acidogenic population, but also led to the establishment to a greater variety of granule trophic groups within all the glucose cultivated batch systems. The addition of fruit cocktail effluent as carbon substrate enhanced ECP production in the Paarl-sludge cultivated batch systems. However, the addition of carbon substrates showed no discernible trend on granule formation itself. The roller-table cultivation technique resulted in the higher increase in granule numbers, and it was speculated that the more vigorous shake-waterbath technique probably shortened the contact time between biomass and substrate. Large variations in the ECP composition of the different batch systems were found, and these were ascribed to the composition heterogeneity of different sludges. For future studies, it is advisable to characterise sludge, both chemically and microbiologically before using as inoculum. The selection of an appropriate sludge inoculum should then lead to optimisation of the granulation process. / AFRIKAANSE OPSOMMING: Die aanvangsperiode van "Upflow Anaerobic Sludge Bed" (UASB) bioreaktors kan noemenswaardig verminder word deur die tydsame granulasie proses te versnel deur die vooraf lot-kweking van anaërobe granulêre slyk waarmee 'n reaktor dus geïnokuleer kan word in plaas van rou anaërobe slyk. Die presiese meganisme van granulevorming is nog nie welbekend nie, maar daar word beweer dat ekstrasellulêre polimere (ECP) wel 'n kritiese rol speel in die granulasie proses. Inligting; oor die presiese rol van ECP is ook nog beperk, en tans word daar nog , geen universele standaard metode vir ECP-ekstraksie gebruik nie. Gevolglik moet resultate vanaf verskeie navorsers met groot omsigtigheid vergelyk word. Die doelwitte van hierdie studie was om 'n ECP ekstraksiemetode te evalueer deur die ekstraksietyd te optimiseer, en dan te korreleer met die ECP samestelling en metaboliese aktiwiteit van die UASB granules. Die inwerking van veranderinge in omgewingskondisies, soos slykbronne (Paarl- en Kraaifontein-slyk), koolstofbronne (gisekstrak-Iaktaat-, glukose-medium en vrugtekelkie-uitvloeisel) en lot-kwekingstegnieke (rol-tafel en skud-waterbad) op lot-kweking studies in terme van granule aktiwiteit, ECP-samestelling en granulevorming is ook ondersoek. 'n Fisiese ekstraksie metode is gebruik om die ECP-inhoud van UASB granules vanaf ses verskillende bronne te bepaal. Die optimale ekstraksietyd is geneem as die tyd benodig voordat sellise sal plaasvind en die intrasellulêre materiaal 'n bydrae sal lewer tot die ECP-inhoud van granules. Dit is afgelei dat die ECP-samestelling beïnvloed word deur die samestelling van die afvalwater wat vir die oorspronklike UASB bioreaktors gevoer is. Voorts is gevind dat die aktiwiteitstoets resultate indirek gebruik kan word vir die voorspelling van aktiwiteit van die verskillende trofiese groepe wat in die UASB granules teenwoordig is. 'n Korrelasie is gevind tussen die aktiwiteitstoets resultate en die totale ECP-inhoud wat aangedui het dat granules met hoër ECP opbrengste, beter biogas (SB) en metanogeniese (SM) aktiwiteit getoon het. Volgens die aktiwiteitsdata en totale ECP-inhoud het dit egter geblyk dat 'n proteïen:koolhidraat verhouding < 1 die aktiwiteit van granules beïnvloed het. Die slykbron wat as inokulum gebruik is vir lot-kweking van' anaërobiese granulêre slyk het 'n noemenswaardige invloed gehad op granulevorming. Die gebruik van 'n rou anaërobe slyk wat reeds 'n mate van granulasie getoon het, soos die Paarl-slyk, het 'n hoër toename in granule getalle aan die einde van die kwekingsperiode teweeg gebring. Die asynsuur aktiwiteitsprofiele het aangedui dat die asetoklastiese metanogene, wat hoofsaaklik betrokke is by inisiëring van granulasie deur kernvorming, onaktief of afwesig was in al die verskillende lotsisteme, met die uitsondering van die roltafel glukose-gekultiveerde Kraaifonteinslyk (RKG) lot-sisteem. Die toevoeging van glukose as koolstofbron vir lot-kweking het nie alleenlik die aktiwiteit van die asidogene populasie verhoog nie, maar het ook bygedra tot die vestiging van 'n groter verskeidenheid van granule trofiese groepe. Die toevoeging van vrugtekelkie-uitvloeisel as koolstofbron het die produksie van ECP verhoog in die Paarl-slyk gekweekte lot-sisteme. Die toevoeging van koolstofsubstrate het egter geen merkbare verandering getoon in granulasie opsigself nie. Die rol-tafel kwekingstegniek het 'n hoër toename in granule getalle tot gevolg gehad, en dit is gespekuleer dat die meer kragtige skud-waterbad tegniek waarskynlik die kontaktyd tussen die substraat en biomassa verkort het. Groot variasies is gevind in die ECP-samestelling van die verskillende lotsisteme, en dit is toegeskryf aan die heterogene samestelling van die verskillende slyke. Vir toekomstige navorsing is dit raadsaam om slyk voor gebruik as inokulum beide chemies en mikrobiologies te karakteriseer. Die keuse van 'n geskikte slyk-inokulum sal bydra tot die optimisering van die granulasie proses.
228

Micro e ultrafiltração como pós-tratamento para reúso de efluentes de abatedouro e frigorífico de suínos

Fappi, Devanir André 26 March 2015 (has links)
Fundação Araucária; CAPES / As indústrias alimentícias utilizam considerável volume de água para suprir a demanda de processos. Devido a isso, observa-se um grande volume gerado de efluentes que necessitam ser tratados para garantir o destino final adequado. Tendo em vista a crescente escassez de água, procedimentos de racionalização do uso da água e o reúso de efluentes tratados surgem como soluções para estes problemas. A aplicação de processos de separação por membranas no tratamento de efluentes da indústria alimentícia para reúso apresenta-se como um processo de tratamento avançado apropriado. Deste modo, o objetivo deste estudo foi avaliar a utilização dos processos de separação por membranas como tratamento avançado de águas residuárias agroindustriais provindas de um abatedouro e frigorífico de suínos, da região oeste do Paraná, visando à possibilidade de reúso destes efluentes. Para isso, foi necessário: realizar a caracterização físico-química dos efluentes agroindustriais; avaliar o emprego de microfiltração, ultrafiltração, e microfiltração seguida de ultrafiltração em diferentes condições operacionais de pressão aplicada à membrana, e avaliar a qualidade do efluente obtido pelos processos de separação com membranas, considerando o atendimento das exigências técnicas, legais e sanitárias para diferentes usos industriais. Os resultados mostraram que os processos de separação por membranas apresentaram, de uma maneira geral, uma sensível melhora na qualidade do efluente final quando comparados com o atual sistema de pós-tratamento empregado pela indústria (flotador físico-químico), que promove eficiências de remoção nas faixas oscilantes de 3% a 29%, 44% a 70%, 40% a 46% e 50% a 58,5%, aproximadamente, para os parâmetros sólidos totais voláteis, turbidez, nitrogênio amoniacal e DQO, respectivamente. A microfiltração apresentou as seguintes faixas de eficiência de remoção, aproximadas: sólidos totais voláteis (51% - 64%), turbidez (83% - 99%), nitrogênio amoniacal (21% - 24%) e DQO (64% - 72%). A ultrafiltração apresentou as seguintes faixas de eficiência de remoção, aproximadas: sólidos totais voláteis (23% - 51%), turbidez (87% - 99%), nitrogênio amoniacal (54% - 69%) e DQO (77% - 85%). A realização do ensaio de microfiltração seguido de ultrafiltração nas melhores condições experimentais investigadas obteve resultados satisfatórios na remoção de aproximadamente 97% para a turbidez, 17% para os sólidos totais voláteis, 67% para a DQO, 38% para o nitrogênio amoniacal, 96% a 99,95% para os coliformes termotolerantes e 93 a 99,69% para os coliformes termorresistentes. Com o aumento da pressão para a microfiltração e ultrafiltração foi obtido maior fluxo permeado e melhor qualidade do efluente final. Embora os efluentes tenham proporcionado distintos valores de fluxo permeado, foram obtidas curvas de desempenho bastante semelhantes, caracterizando-se por uma queda do fluxo permeado nos primeiros minutos de filtração, seguido de um período onde ocorre declínio gradual, com uma tendência ao equilíbrio. De acordo com os requisitos físico-químicos e microbiológicos mínimos exigidos para o reúso de efluentes tratados, a microfiltração e a ultrafiltração atenderam alguns dos parâmetros monitorados, alcançando a qualidade exigida para o reúso em torres de resfriamento, lavagem de pisos, irrigação de áreas verdes, lavagem de veículos, proteção contra incêndio e descarga sanitária. / The food industry uses large volumes of water to meet the demand processes. Because of this, there is a large volume of generated waste that need to be addressed to ensure proper final destination. In view of the growing scarcity of water, the use rationalization of procedures of the water and the reuse of treated effluent arise as solutions to these problems. Application of separation processes by membranes in the treatment of wastewater for reuse food industry presents itself as an appropriate advanced treatment process. Thus, the aim of this study was to evaluate the use of membrane separation processes as advanced treatment of agroindustrial wastewater stemmed from a swine slaughterhouse, the western region of Paraná, aiming at the possibility of recycling these effluents. For this it was necessary: to define the physical-chemical characterization of the agro-industrial effluents; evaluate the use of microfiltration, ultrafiltration, microfiltration and ultrafiltration then under different conditions of pressure applied to the membrane, and evaluate the quality of the effluent obtained by separation processes with membranes, considering the care of the technical, legal and health requirements for different uses industrial. The results showed that membrane separation processes presented in a general way a considerable improvement in final effluent quality compared with the current tertiary treatment system used by the industry (physicochemical flotation) which promotes removal efficiencies in oscillating ranges from 3% to 29%, 44% to 70%, 40% to 46%, 50% to 58.5%, approximately, for the parameters: total volatile solids, turbidity, ammonia nitrogen and COD, respectively. Microfiltration had the following removal efficiency ranges, approximate: total volatile solids (51% - 64%), turbidity (83% - 99%), ammonia nitrogen (21% - 24%) and COD (64% - 72%). Ultrafiltration showed the following removal efficiency ranges, approximate: total volatile solids (23% - 51%), turbidity (87% - 99%), ammonia nitrogen (54% - 69%) and COD (77% - 85%). The completion of the test microfiltration followed by ultrafiltration under the best experimental conditions investigated achieved satisfactory results in the removal of approximately 97% for the turbidity, 17% total volatile solids, 67% for COD, 38% for ammonia nitrogen, 96% to 99.95% for thermotolerant and 93 to 99.69% for the heat-resistant coliforms coliforms. With increasing pressure to microfiltration and ultrafiltration permeate flux was increased and better quality of the final effluent. Although the effluents have provided separate permeate flow rates, very similar performance curves were obtained, characterized by a drop in permeate flux during the first minute filtration followed by a period where there is a gradual decline, with a tendency toward equilibrium. According to the physicochemical requirements and minimum microbiological required for the reuse of treated wastewater, microfiltration and ultrafiltration attended some of the monitored parameters, achieving the required quality for reuse in cooling towers, floor washing, irrigation of green areas , washing vehicles, fire protection and sanitary discharge.
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Educação pela ação ambiental: a coleta seletiva de resíduos sólidos em um departamento de instituição superior de ensino

Gonzalez, Carlos Eduardo Fortes 12 December 2006 (has links)
Este estudo tem o objetivo de discutir as inter-relações entre pressupostos da Educação Ambiental e a coleta seletiva de resíduos sólidos. Resgatando-se historiograficamente a Educação Ambiental e as concepções de coleta seletiva de resíduos sólidos, a partir de revisão das literaturas sobre a temática, obtêm-se dados sobre estas inter-relações. A constatação da inter-relação proposta também foi verificada por um experimento realizado em um dos Departamentos acadêmicos da Universidade Tecnológica Federal do Paraná. Assim, constituiu-se num estudo de caso, que também demonstrou empiricamente a relação direta entre a Educação Ambiental e a melhoria de funcionamento de sistemas de coleta seletiva. As conclusões oriundas destas investigações indicam que os processos educativos ambientais merecem atenção especial quando da implementação e do monitoramento de programas de coleta seletiva, pois são essenciais ao bom funcionamento destes programas. Relaciona-se a questão da coleta seletiva com a Tecnologia, pois a segregação de resíduos é realizada em função de processos tecnológicos existentes para a reciclagem, enquanto a diversidade de resíduos contemporâneos dá-se em função de novos processos tecnológicos. Assim, a Tecnologia é fator determinante na complexidade dos sistemas de coleta seletiva, e por esta razão é abordada neste Trabalho. / The present study has the goal of discussing the interrelations between the premises of environmental education and the better functioning of a selective collection of solid waste. From the posed question, reviewing the historiography of the environmental education and the conceptions of selective collection of solid waste, through the review of scientific literature about both subjects, it is obtained data of the referred interrelations. The confirmation of the proposed interrelation was verified by an experiment done in one of the academic departments of the Technological Federal University of Parana, too. Thus, it was constituted in a case study, which demonstrated empirically a direct relation between the applications of environmental education and the betterment of the functioning efficiency of a selective collection system. That is, as much better the environmental education applied, more efficient is the selective collection system. The conclusions of such investigations indicate that the environmental educative processes deserve special attention by occasions of implementation and monitoring of selective collection programs, because they are essential for the good functioning of such systems. Selective collection is related to Technology, because the segregation of waste is done by the fact that there are recycling technological processes, while the diversity of contemporary wastes occurs due to new technological processes. Thus, Technology is a determining factor in the complexity of selective collection systems, and that's why it is studied in this thesis.
230

Utilização de gordura animal e resíduo agroindustrial como substratos de baixo custo para a produção de biossurfactante com potencial de aplicação na área ambiental

Danyelle Khadydja Felix dos Santos 09 April 2013 (has links)
Breve / Breve

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