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Enskilda avlopp : Ett kommunalt ansvar? / Individual sewage disposal system : A municipal responsibility?Eriksson, Gustav January 2013 (has links)
Vattnet är en livsviktig resurs för levande organismer och ekosystem. Idag används vatten i alla möjliga sammanhang vilket har lett tillatt vattnet har blivit övergött och förorenat. Utsläpp av näringsämnen i för stora mängder anses vara den största orsaken til lövergödning och detta gäller framför allt utsläpp av avloppsvatten. Syftet med denna uppsats var att undersöka Sveriges kommunerskartläggningsstrategier för enskilda avlopp och vilka åtgärder de vidtar, samt hur många enskilda avlopp det finns. För att ta reda pådetta skickades en enkät och ett följebrev ut till alla kommuner i Sverige och sedan sammanställdes dessa. Av Sveriges 290 kommunervar det 232 som deltog. De vanligaste strategierna för att kartlägga enskilda avlopp är att skicka ut enkäter eller göra inventeringar. I många fall används bådastrategierna med enkät som ett första steg och inventering som ett andra. Resultatet av enkäten visar att mellan 50-90 % av de enskildaavloppen är undermåliga eller bristfälliga och att åtgärder krävs. Kommunerna ställer krav på fastighetsägarna att åtgärda sina avloppinom en viss tidsram annars kan förbud att använda avloppen utfärdas. Undersökningen visade att det finns ungefär 813 000 enskilda avloppsanläggningar i Sverige, vilket är en ökning med cirka 71 000 sedan2006. Ökningen kan bero på att fler än hälften av Sveriges kommuner har gjort en kartläggning sedan 2006
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Gefährliche Stoffe in KläranlagenSchneider, Petra, Günther, Thomas, Gottschalk, Nicole, Zänder, Daniel 22 April 2010 (has links) (PDF)
Gefährliche Stoffe gelangen durch Abwässer aus Haushalten, Industrie und Landwirtschaft in Kläranlagen. Während der mechanisch-biologischen Abwasserbehandlung in konventionellen Kläranlagen werden nur wenige Stoffe mit toxischen, persistenten und bioakkumulierenden Eigenschaften eliminiert. Der Bericht beschreibt die Eigenschaften gefährlicher Stoffe - darunter Industriechemikalien, Pflanzenschutzmittel, Arzneistoffe, Hormone und Metalle, ermittelt Quellen des Stoffeintrages und leitet Möglichkeiten zur Verringerung der Stoffeinträge ab.
In Laborkläranlagen wurde eine Methodik entwickelt, mit der bei Anlagen mit biologischer Grundreinigung und weitergehender Reinigung (Stickstoffeliminierung) die Eliminierungsrate für ausgewählte gefährliche Stoffe ermittelt werden kann.
Die Eliminationsraten der untersuchten gefährlichen Stoffe sind sehr unterschiedlich. Während ausgewählte Pestizide nur in geringem Umfang eliminiert werden (Bentazon < 40 Prozent, Dichlorprop < 30 Prozent, Dibutylzinn < 50 Prozent), werden für Nonylphenolethoxylate, Phthalate und Trichlormethan hohe Eliminationsraten mit bis zu 99 Prozent ermittelt.
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Environmental risks, subjectivity, and political choices : the Korean case /You, Seungkwon, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 231-239). Also available on the Internet.
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Environmental risks, subjectivity, and political choices the Korean case /You, Seungkwon, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 231-239). Also available on the Internet.
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Odour control and management in Hong Kong sewage treatment infrastructuresWong, Ying-kin, 黃英健 January 2013 (has links)
Many complaints were received from the residential area around the Shatin Sewage Treatment Works (STSTW) about the presence of odour. The dominant odour marker H2S was selected to be studied. A review of the odour measurement and sampling methods, together with the specification of the standard limits and health effects were made. The formation process of H2S was investigated and the abatement and control measures in terms of physical, chemical and biological techniques were compared. The monthly rate of H2S emission in the atmosphere was calculated from the soluble sulfide and the measured wastewater flow at the inlet works, primary sedimentation tanks, aeration tanks, and sludge digestive and storage tanks, and the H2S mapping was carried out at the same places. Meteorological data including wind speed, wind direction, temperature and pressure were collected. The effect of temperature and pH on H2S generation is shown, and the effectiveness of odour control and deodourization processes was studied. A Gaussian dispersion model of Industrial Source Complex version 3 (ISC3) was applied in predicting the ground H2S level at various air sensitive receivers in the vicinity of STSTW. None of the places exceeded the recommended H2S concentration of World Health Organization (WHO) and the odour is a localized problem in STSTW of 35% area having H2S ranging in 0.01--‐0.023ppm. Recommendations are suggested in both short-term improvement in operation and maintenance practice and long-term design and construction of sewage treatment facilities. / published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
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Hydrogeochemistry of stream channel recharge of sewage effluent, northwest of Tucson, ArizonaEsposito, David M. January 1993 (has links)
This investigation has documented the water quality impacts of stream channel recharge of sewage effluent northwest of Tucson and has evaluated the hydrogeochemical mechanisms potentially responsible for observed water quality changes. The evaluation was accomplished partly through construction of twelve monitor wells and implementation of a quarterly water quality monitoring program for surface water and groundwater. Constituents monitored included major inorganic chemical constituents, trace inorganics, trace metals, priority pollutants/trace organics and microbiological contaminants. ¹⁵N also proved useful in the study. The significance of a reducing zone immediately beneath the bed of the Santa Cruz River with respect to denitrification was documented. Findings of this investigation indicate that while sewage effluent is of poor quality with respect to drinking water standards, groundwater recharged by sewage effluent is of improved quality. Other findings include: * Nitrate in shallow groundwater near the Santa Cruz River in the Cortaro area appears to be primarily from stream channel recharge of sewage effluent; * Nitrate-N contents of effluent recharged groundwater averaged about 5 mg/1, well below the maximum contaminant level for drinking water of 10 mg/1, representing a 75 percent loss in total nitrogen during stream channel recharge of sewage effluent (assuming no mixing); * Both stream channel recharge of sewage effluent and agricultural deep percolation contribute to nitrate in shallow groundwater near the Santa Cruz River in the Marana area; * The reducing zone beneath the Santa Cruz River may be responsible for denitrification losses of up to 5 mg/1 of nitrate-N. This would explain approximately 30 percent of nitrogen losses, on average, between effluent and recharged groundwater; * The mechanisms of cation exchange and mixing with groundwater from other sources can explain the major changes in water quality between effluent and groundwater with respect to major inorganic chemical constituents; * Renovation of effluent with respect to coliform bacteria and enteric viruses content during recharge is not complete.
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Decentralizing the Strategic Sewage Disposal Scheme of Hong Kong: the reasons and the potential modificationsLi, Mo-yee, Deanna., 李慕儀. January 2000 (has links)
published_or_final_version / abstract / toc / Applied Geosciences / Master / Master of Science
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Resistance of indicator organisms to chlorinationClinger, Robert Christopher, 1946- January 1970 (has links)
No description available.
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Development of a code of practice for co-disposal to obviate inimical environmental impacts of generated gases and leachates.Daneel, Richard A. January 1996 (has links)
Despite its phasing out in numerous countries, such as Germany and the U.S.A.,
co-disposal of hazardous waste with municipal solid waste continues to be widely practised
in South Africa. Co-disposal utilises properties and microbial activities in the refuse to
attenuate the hazardous waste and thus obviate its environmental impact potential. All
landfill operations require careful planning in not only site selection criteria but also the
type and amount of various wastes accepted for disposal. It is clear, however, that the
practice of co-disposal requires special precautions and management as the methods
employed in the landfill operation determine to a large extent the environmental effects
and, thus, the public acceptability of the operations.
Although co-disposal is not suitable for all industrial wastes the results of recent
research efforts, conducted mainly in the U.K., have indicated that, when properly
managed, co-disposal can be regarded as a safe and efficient disposal option for many
hazardous wastes. Environmental awareness in many European countries ensures that
numerous hazardous compounds are either recycled or recovered. Unfortunately, in South
Africa the lack of similar concern has resulted in increased concentrations of toxic
compounds being co-disposed on a regular basis. Since fundamental studies of this
technology, pertaining to South African conditions, have been lacking laboratory
models/microcosms were built to address this paucity.
Model. To effect the separation of species habitat domains of component species of
growth rate-dependent interacting microbial associations responsible for terminal catabolic
processes of the refuse fermentation, with retention of overlapping activity domains, and so
facilitate examination of species in isolation without violating the integrity of each
association, multi-stage models were constructed. The accidental overgassing of the culture
with liquid petroleum gas (LPG) effected interesting fermentation balance changes which
also emphasised the need for an Anaerobic Bioassay Test to assess the impacts of specific
perturbants. Evidence of differential susceptibility of the component species to phenol was
demonstrated in this study.
Microcosm. A total of 42 refuse packed single-stage glass column bioreactors were
commissioned and subjected to phenol and/or anaerobically digested sewage sludge codisposal.
The effects of four different operational modes: leachate discard (single elution);
leachate recycle; batch; and simulated rain on the co-disposals as well as refuse catabolism
per se were examined.
The results of these studies indicated that protracted periods of adaption to phenol (1000
and 2000 mg l -1) could have resulted from nutrient (elemental) limitation. Circumstantial
evidence was also gained which indicated that the nitrate- and sulphate-reducing bacteria
(SRB) were particularly sensitive to the added xenobiotic. Further, without the effective
participation of the nitrate- and SRB the active and total fermentation of both the phenol
and refuse components were depressed. It was also determined that the operating regime
employed was a key factor in refuse degradation although with time, and especially
following the phenol resupplementations, the operating conditions played a less significant
role. In general, the single elution operated columns demonstrated increased phenol
removal rates which were, unfortunately, coincident with low pH values and increased
leachate residual phenol concentrations. Leachate recycle, on the other hand, unlike the
batch operated columns, facilitated increased pH values and methane evolutions. The
simulated rain columns were characterised by rapid washout of the added phenol as well as
methanogenic precursors.
The sewage sludge co-disposal experiments, likewise, demonstrated that, depending on
the sludge:refuse ratio, the operating regime was extremely important in optimising the
refuse degradation processes although, in general, leachate recycle appeared to be the most
favoured method of operation. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1996.
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Microbiological investigations into granular sludge from two anaerobic digesters differing in design and industrial effluent purified.Howgrave-Graham, Alan R. January 1995 (has links)
Due to a combination of selection criteria, sludges from upflow anaerobic digesters
treating industrial waste waters consist primarily of well-settling, dense agglomerates
called granules. Quantification of the component mixed microbial populations of these
granules has been severely restricted by the inability of researchers to disrupt them
without concomitantly destroying numerous cells. In situ quantification using light and
electron microscopy is complicated by the high cell numbers and bacterial diversity; the
small cell size; and the destructive nature of electron microscopy preparative
techniques preventing the viewing of more than a small percentage of the population
at a time. For these reasons, in this investigation, standardization of qualitative electron
microscopic techniques was performed prior to their application to granules. Isolation
and electron and light microscopic techniques were applied to granules from a fullscale
clarigester treating effluent from a maize-processing factory. In addition, a
method using montaged transmission electron micrographs (TEMs) taken along a
granule radius, and image analysis, was developed for bacterial quantification within
granules. This method, together with antibody probe quantification, was applied to
granules from an upflow anaerobic sludge blanket (UASB) digester treating a brewery
effluent. The clarigester granules contained a metabolically and morphologically diverse
population of which many members were not isolated or identified. By contrast, the
UASB digester granules consisted primarily of morphotypes resembling Methanothrix,
Methanobacterium and Desulfobulbus, in order of predominance. However, only about
one-third of the population reacted with antibody probes specific to strains of bacterial
species expected to occur within these granules. According to the antibody probe
library used, the Methanobacterium-like cells observed in TEMs were probably
Methanobrevibacter arboriphilus. From this study it is apparent that different anaerobic
digester designs, operational parameters, and the chemical composition of the waste
water purified, are factors which influence the formation and maintenance of granules
differing with respect to their microbial populations. Until the difficulties associated with
quantification are overcome, the processes governing granule formation and/or
population selection will remain obscure. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1995.
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