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The efficiency of constructed wetlands for the removal of the antimicrobial agent triclosan from wastewaterZinn, Elizabeth R. 15 December 2012 (has links)
Access to abstract restricted until December 2014. / Review of relevant literature -- Efficiency of constructed wetlands to remove an antimicrobial agent triclosan from wastewater -- The removal of triclosan from laboratory scale constructed wetlands with four species of wetland plants -- Additional research : determination of the hydraulic retention time in an operational subsurface constructed wetland -- Additional research methods : the evaluation of the subsurface constructed wetland for the treatment of iron, phosphorus, ammonia, nitrite, nitrate, dissolved oxygen, pH and E. coli. / Access to thesis restricted until December 2014 / Department of Natural Resources and Environmental Management
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Residence time methods for modelling and assessing the performance of water treatment processes.Barnett, Jacqueline Lisa. 23 September 2014 (has links)
The objective of this study was to provide a technique, based on the residence time
distribution of a process, for modelling, assessing and improving flow in the processes
of water and waste water treatment works. The technique should be accessible to the
staff managing and operating the works.
From a review of the literature, a preference was given for the experimental method
used for determination of the tracer response, including choice of tracer and tracer
addition and monitoring. Data analysis techniques were reviewed, and the method of
time domain fitting was developed into a computer program, IMPULSE. IMPULSE
provided a tool for analysis of residence time data, and removed the constraint of
numerical complexity. Using the building blocks of IMPULSE, a realistic flow model
can be constructed from tracer data and evaluated. IMPULSE allows a quantitative
comparison of models proposed for a process, and provides the parameters of the models.
These parameters quantify the non-idealities in a process. A knowledge of the
non-idealities provides a basis for decision-making when modifying a process.
The results of tracer experiments performed on some water and waste water treatment
processes were analysed using IMPULSE. The results showed that collection of good
experimental data was critical to the success of the analysis.
It is proposed that a guide be produced which draws out the main points raised in the
study, including collection of tracer data and use of IMPULSE. The guide should be
accessible and easily understandable to the staff managing and operating water and
waste water treatment works. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 1995.
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Un système septique modifié pour gerer efficacement les eaux usées de ferme laitière /Morin, Sophie, 1978- January 2007 (has links)
In 2001, the Quebec Ministry of Environment modified its waste management regulation and obliged dairy farms to treat their milk house wastewaters to prevent contamination of water courses. For small dairy farms with fewer than 60 cows, conventional technologies implied an investment of at least $15 000 to comply with the new regulation. / The objective of this master's project was therefore to develop a low cost and sustainable technology for the treatment and disposal of milk house wastewaters that would permit on-farm recycling of nutrients and water. With the help of the research results of Urgel Delisle and Ass., the new system was done by modifying existing septic tank systems on two dairy farms with 40-50 cows by installing a sediment and milk fat trap before the septic tank, and building a drained 0.45ha seepage field in a pasture or cropped field, after the septic tank. / The modified septic tank system on each farm was monitored during a three year period, which involved checking the system for clogging by digging out sections of sewer pipes after two years of operation; measuring and sampling milk house wastewaters to establish the annual nutrient load, and comparing the water quality in drainage from the seepage field to that of a nearby control field. / The milk house wastewaters produced by the farms led to an average nutrient load of 60kg TN/ha/y, 50kg TP/ha/y and 80 kg TK/ha/y. The average volume of wastewater applied to the seepage field, between 16 and 19mm/month, did not saturate the soil as no sign of gleying (reduction of iron oxides) was observed when excavating the sewer pipes. In general, soil pH decreased when milk house wastewater entered the seepage field, while the NH4-N, K and Ca concentrations increased. However, soil salinity was low (<4 dS m -1) on these farms. The soil P concentration was unchanged on one farm, but there was rapid and significant accumulation of P in the 20-60 cm depth of the soil profile on the second farm. The accumulation of milk fat inside the sewer pipes on one farm resulted from the disposal of wasted milk into the septic system, the absence of a water softener and the fact that this fat was not regularly removed from the trap. The milk fat was then flowed into the septic tank harming the correct operation of the system. Drainage water quality was similar from the seepage field of the modified septic tank system as an adjacent control field. / The low cost of system modification, about $4 400 Can., and the treatment efficiency achieved meant that the concept is feasible and offers a suitable solution for small dairy farms.
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Design of the step-feed activated sludge processMoreno, Oswaldo January 1987 (has links)
No description available.
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Acetate and poly-b-hydroxybutyrate (PHB) metabolism by the activated sludge floc community of a hardwood Kraft pulp and paper millPouliot, Cédrick January 2005 (has links)
This research followed acetate carbon (C) uptake, metabolism, and fate through a typical modern Kraft pulp and paper mill AS system. Freshly collected mill biomass (AS floc suspensions) was placed under conditions representing four key phases of AS biotreatment: (1) initial acetate uptake by aerated starved AS; (2) ongoing acetate uptake; (3) aerobic metabolism of acetate-loaded AS in acetate-stripped effluent; and (4) anaerobic, settled biomass metabolism. Conditions mimicked the mill system as closely as possible. Acetate carbon uptake kinetics and conversion to CO2, growth products, PHB, and secreted metabolites in each of the four phases were measured. The role of PHB synthesis in the initial stripping of acetate from mill effluent and the PHB production potential of this mill AS were also investigated. / Results showed that acetate was rapidly taken up by high-affinity systems in the AS. During the initial exposure of mill-starved AS, acetate greatly stimulated AS-O2 uptake, and was quickly converted to PHB and CO 2. Upon depletion of available effluent acetate, as occurs in the downstream sections of the aeration tank, O2-uptake rates decreased and the acetate-C stored in AS-PHB was slowly released as CO2, and partly used for growth. Under secondary clarifier-like anaerobic conditions, the AS released virtually no CO2. However, substantial amounts of PHB were used for growth under anaerobic conditions and a small proportion of the original acetate C exited the cells as organic acids.
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Engineering and economic evaluation of innovative bioreactor for milk parlor wastewater treatment/reuseKongsil, Piyalerg January 2006 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 179-186). / xix, 215 leaves, bound ill. 29 cm
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Design and comparison of DIN removal rates between five 'low-tech' fixed film biological reactors treating aquaculture wastewater on Coconut IslandRoth, Lauren Carter January 2005 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 64-73). / xi, 73 leaves, bound ill. 29 cm
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Soil processes to remediate dairy effluent using MSL (Multi-Soil-Layer) systemsPattnaik, Rosalin January 2006 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 103-108). / xiv, 108 leaves, bound ill. 29 cm
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Characterization and engineering of Bacillus megaterium AS-35, for use in biodegradation of processed olive wastewaterVan Schalkwyk, Antoinette January 2005 (has links)
<font face="Times New Roman"><font face="Times New Roman">
<p align="left">The popularization and health benefits associated with the &ldquo / Mediterranean diet&rdquo / saw a world wide increase in the production and consumption of processed olives and olive oil. During the brining of table olives large quantities of processed olive waste water is seasonally generated. This blackish-brown, malodours liquid is rich in organic and phenolic compounds, which cause environmental problems upon discarding. Currently, processed wastewater is discarded into large evaporation ponds where it poses serious environmental risks. The biodegradation of organic substrates present in the olive wastewater is inhibited by the high concentrations of phenolic compounds. <font face="Times New Roman">In order to identify organisms which could potentially be used in the bioremediation of olive wastewater, 36 microbial strains were isolated from evaporation ponds in the Boland region of South Africa. Twenty five isolates were capable of growth on 50% olive wastewater and their bioremediation potential as well as their ability to produce valuable intermediate compounds were subsequently characterized. Based on the RPHPLC results, which showed that a number of chemical intermediates were produced in fermentation of olive wastewater, isolate AS-35 was selected for further analysis. Strain AS-35, identified as a </font><font face="Times New Roman"><em>Bacillus megaterium,</em> </font><font face="Times New Roman">was significantly influenced by the exposure to olive waste. The total cellular protein profile, generation time and cellular morphology of this isolate were dramatically affected by the introduction of olive waste. <font face="Times New Roman">This study investigated the differential gene display of </font><font face="Times New Roman"><font face="Times New Roman"><em>Bacillus megaterium</em></font> </font><font face="Times New Roman">following exposure to olive wastewater. Proteomic and transcriptomic differences of the organism cultured in nutrient rich LB and olive wastewater were compared. These results indicated that AS-35 expressed genes involved in glycolysis, tryptophan and nucleotide synthesis as well as the chaperones GroEL and DnaK during its growth in LB. In contrast, genes induced following the abolishment of glucose dependent catabolite repression, genes involved in biotin synthesis and ß / -oxidation of fatty or organic acids as well as a gene whose expression is regulated by stress induced s</font><font face="Times New Roman" size="1">B</font><font face="Times New Roman">-dependent regulon were expressed during olive waste growth.</font></font></p>
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Isolation and characterisation of lipolytic bacteria and investigation of their ability to degrade fats, oils and grease in grain distillery wastewaterHendricks, Ashley Alfred 04 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The large volumes of effluent water generated by distillery industries is an issue of
great concern as it contains pollutants that must be treated according to environmental
legislation. It has been reported that grain distillery wastewater (GDWW) is high in fats, oils
and greases (FOG) that can be reduced by treating with suitable microorganisms. The
objective of this study was to investigate the biodegradability of FOG in GDWW. This was
done by isolating lipolytic bacteria from soil, which was situated close to the GDWW
treatment plant at a distillery in Wellington, South Africa. These isolates were screened for
lipolytic activity on various fat substrates. Secondly, the most desirable isolates were
subjected to batch biodegradation trials using GDWW as substrate and tested for their
ability to biodegrade FOG. Each of the four isolates, Pseudomonas fluorescens (1),
Pseudomonas luteola (2), Stenotrophomonas maltophilia (3) and Bacillus licheniformis (4)
were screened on three types of media: DifcoTM Spirit Blue Agar with Tributyrin (SBA-Tri);
Victoria Blue B Agar with Cotton Seed Oil (VBB-CSO); and Victoria Blue B Agar with
GDWW (VBB-GDWW) at different temperatures (25°C, 30°C, 37°C and 50°C) to
determine optimal enzyme activity for lipolysis. Lipolysis was taken as positive when
growth of dark blue colonies was formed or by the formation of a clear zone around the
colony. Lipolysis was observed at all the aforementioned temperatures for P. fluorescens,
P. luteola and S. maltophilia. Bacillus licheniformis failed to show any lipolytic activity at
50°C on the SBA-Tri. A decrease in lipolytic (clear) zone was observed at an increase in
temperature from 25°C to 37°C for P. fluorescens. When VBB-GDWW was used as lipid
substrate, isolates failed to indicate any clear zone of lipolysis, however, growth was
present for all isolates in the form of a dark blue zone around colonies, which were also
positive for lipolytic activity.
Three lipolytic bacteria (P. luteola, S. maltophilia, and B. licheniformis)
isolated from the above study were subjected to GDWW of various FOG concentrations
(70 – 211 mg.L-1). These isolates were allowed to acclimatise to GDWW during a batch
biodegradation period (18 – 21 d) at 37°C. Bacillus licheniformis showed the highest FOG
reduction of 83% after 18 d exposure. All the strains showed that an initial acclimatisation
phase improved the biodegradation of the FOG. A fatty acid profile was obtained for each
batch biodegradation trial after the acclimatisation phase. It was found that these strains
either biodegraded the fatty acids (FAs) or, as in the case of P. luteola, formed myristic
and pentadecyclic acids from free FAs. The formation of FAs may have occurred through a process of inter-esterification. It was also found that certain precursors such as palmitoleic
acid might be formed under aerobic or anaerobic conditions.
In this study it was shown that biodegradation of FOG can be improved by an initial
acclimatisation period. Single cultures with the desirable properties can be used to lower
the FOG in GDWW and need not be used in mixed cultures that could produce inhibitory
components that would otherwise upset the biodegradation activity of isolates present.
Bacillus licheniformis could be used as a FOG-degrading isolate during the treatment of
wastewaters high in FOG. However, future studies should focus on bioaugmenting the
FOG degrading bacteria from this study with other strains to monitor its activity and ensure
survival and activity in larger scale studies. / AFRIKAANSE OPSOMMING: Die groot volumes afloopwater wat opgelewer word deur die distilleer-industrie is ‘n
kwessie wat groot kommer wek aangesien dit groot hoeveelhede besoedelende stowwe
bevat. Daarom moet dit, volgens omgewingsverwante wetgewing, behandel word. Daar is
voorheen gerapporteer dat graandistillerings-afloopwater (GDAW) hoog is in vette, olies
en ghries (VOG) en dat hierdie VOG verminder kan word deur die GDAW te behandel met
toepaslike mikroörganismes. Die oorhoofse doelstelling van hierdie studie was om die bioafbreekbaarheid
van die VOG in GDAW te ondersoek. Dit is eerstens gedoen deur
lipolitiese bakterieë uit grond wat naby ‘n graandistillerings-aanleg (Wellington, SuidAfrika)
geleë is, te isoleer. Verskeie vetsubstrate is gebruik om hierdie isolate vir lipolitiese
aktiwiteit te toets. Tweedens is die verkose isolate getoets vir lipolitiese aktiwiteit deur
gebruik te maak van lot-bio-afbreekbaarheidsmetode. Tydens hierdie metode is GDAW as
substraat gebruik en die verskillende bakterieë se vermoë om VOG af te breek is getoets.
Om die optimale ensiemaktiwiteit vir lipolise van elk van die vier isolate nl. Pseudomonas
fluorescens (1), Pseudomonas luteola (2), Stenotrophomonas maltophilia (3) en Bacillus
licheniformis (4), vas te stel, is elk getoets op drie verkillende media: “DifcoTM Spirit Blue
Agar” met Tributirien (SBA-Tri); “Victoria Blue B Agar” met Katoensaadolie (VBB-KSO); en
“Victoria Blue B Agar” met GDAW (VBB-GDAW) teen verskillende temperature (25°C,
30°C, 37°C en 50°C). Indien donker-blou kolonies gevorm is of ‘n deursigbare sone
rondom ‘n kolonie waargeneem is, is lipolise as “positief” beskou. Lipolise is waargeneem
teen alle voorafgenoemde temperature vir P. fluorescens, P. luteola en S. maltophilia.
Bacillus licheniformis het nie lipolitiese aktiwiteit getoon teen 50°C op SBA-Tri. ‘n Afname
in die deursigbare sone is waargeneem teenoor ‘n toename in temperatuur vanaf 25°C tot
37°C vir P. fluorescens. In die geval van VBB-GDAW as lipiedsubstraat, het isolate geen
deursigbare sone vir lipolise getoon nie. Daar was egter ‘n donker-blou sone rondom
kolonies teenwoordig, wat ook positief is vir lipolitiese aktiwiteit.
Drie lipolitiese bakterieë (P. luteola, S. maltophilia, and B. licheniformis) is geïsoleer
uit bogenoemde studie en is aan inkubasie in GDAW teen verksillende VOGkonsentrasies
(70 – 211 mg.L-1) blootgestel. Hierdie isolate is toegelaat om te
akklimatiseer tot die GDAW tydens ‘n lot-bio-afbreekbaarheidstydperk (18 – 21 d) teen
37°C. Bacillus licheniformis het die hoogste VOG-afname van 83% na 18 d blootstelling
getoon. Alle bakterieë het getoon dat ‘n aanvanklike akklimatiserings-tydperk die bioafbreekbaarheid
van die VOG verbeter. ‘n Vetsuur-profiel is verkry vir elk van die lot-bio afbreekbaarheidstoetse na die akklimatiserings-fase. Daar is bevind dat hierdie bakterieë
óf die vetsure afgebreek het óf, soos in die geval van P. luteola, miristiese en
pentadesikliese sure, vanaf vry-vetsure, gevorm het. Die vorming van vetsure is moontlik
as gevolg van die proses van inter-esterifikasie. Dit is verder bevind dat sekere
voorlopers, soos palmitoë-oleïensuur, gevorm kan word onder aërobies of anaërobiese
toestande.
In hierdie studie is getoon dan die bio-afbreekbaarheid van VOG verbeter kan word
deur ‘n aanvanklike akklimatiserings-tydperk toe te pas. Enkel-kulture met die verkose
eienskappe kan gebruik word om die VOG in GDAW te verminder. Gemengde kulture,
wat inhiberende komponente produseer wat moontlik die bio-afbreekbaarheids proses
negatief kan beïnvloed, hoef dus nie gebruik te word nie. Bacillus licheniformis kan
gebruik word as ‘n VOG-afbrekende isolaat tydens die behandeling van afloopwater wat
hoog in VOG is. Verdere studies moet egter fokus op die samevoeging van VOGafbrekende
bakterieë vanuit hierdie studie asook ander bakterieë om die aktiwiteit daarvan
te monitor en sodoende oorlewing en aktiwteit op ‘n groter skaal te verseker.
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