Thèses : « Sewage Environmental aspects Vietnam »

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Vo, Le Phu. « Urban stormwater management in Vietnam ». Title page, table of contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09ENV/09envl595.pdf.

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Li, Bing, et 李炳. « Occurrence, transformation and fate of antibiotics in municipal wastewater treatment plants ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46591102.

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Tshivhunge, Azwiedziswi Sylvia. « Enzymology of activated sewage sludge during anaerobic treatment of wastewaters : identification, characterisation, isolation and partial purification of proteases ». Thesis, Rhodes University, 2001. http://hdl.handle.net/10962/d1004072.

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During anaerobic digestion bacteria inside the digester require a carbon source for their growth and metabolism, sewage sludge was used as a carbon source in this study. The COD content was used to measure the disappearance of the substrate. COD content was reduced by 48.3% and 49% in the methanogenic and sulphidogenic bioreactors, respectively, while sulphate concentration was reduced by 40%, producing 70mg/L of hydrogen sulphide as the end product over the first 5-7 days. Sulphate (which is used as a terminal electron acceptor of sulphur reducing bacteria) has little or no effect on the sulphidogenic and methanogenic proteases. Sulphite and sulphide (the intermediate and end product of sulphate reduction) increased protease activity by 20% and 40%-80%, respectively. Maximum protease activity occurred on day 21 in the methanogenic reactor and on day 9 in the sulphidogenic reactor. The absorbance, which indicates the level of amino acid increased to 2 and 9 for methanogenic and sulphidogenic bioreactors, respectively. Proteases that were active during anaerobic digestion were associated with the pellet (organic particulate matter) of the sewage. These enzymes have an optimum activity at pH 10 and at temperature of 50°C. The proteases that were active at pH 5 and 7, had optimum temperatures at 30°C and 60°C, respectively. Due to their association with organic particulate matter, these enzymes were stable at their optimum temperatures for at least five hours at their respective pH. Inhibition by PMSF, TPCK and 1.10-phenanthroline suggested that proteases inside the anaerobic digester are a mixture of cysteine, serine and metalloproteases. At pH 5, however, EDTA appeared to enhance protease activity by 368% (three-fold). Acetic acid decreased protease activity by 21%, while both propionic and butyric acid at 200 mg/L cause total inhibition of protease activity while these acids at higher pH (where they exist as their corresponding salts) exerted little effect. Copper, iron and zinc inhibited protease activity by 85% at pH 5 with concentrations ranging between 200 and 600 mg/L. On the other hand, nickel, showed an increase in protease activity of nearly 250%. At pH 7 and 10, copper had no effect on protease activity while iron, nickel and zinc inhibited these enzymes by 20-40%. Proteases at pH 7 were extracted from the pellet by sonication, releasing 50% of the total enzymes into the solution. The enzymes were precipitated by ammonium sulphate precipitation, and further purified by ion exchange chromatography and gel filtration. Ion exchange chromatography revealed that most of the enzymes that hydrolyse proteins are negatively charged while gel filtration showed that their molecular weight is approximately 500 kDa.

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MacNicol, Roger. « The forms of combination of Cu, Ni and Zn in anaerobic sewage sludge ». Thesis, University of Oxford, 1989. http://ora.ox.ac.uk/objects/uuid:ddd31ded-57f0-415d-9ab7-a390b9c8632a.

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As a first step in understanding the chemistry of toxic elements in sludged soil, this thesis presents a comprehensive model of their chemistry in the digester. A review of the literature had shown that heavy metals were likely to be held in 3 pools: as precipitated and detrital mineral phases 'Particulate'; as complexes with the flocculated biomass 'Biofloc'; and as complexes in solution 'Soluble'. A simple pragmatic fractionation procedure has been offered to separate these 3 pools based on their physical properties in water. A mass-balance between the pools showed that the 'Particulate' fraction held only 5-16% of the heavy metals but contained them in the highest concentration. The 'Biofloc' held 82-94% of the heavy metals. The 'Particulate' material was subdivided by density separation and examined by a combination of analytical SEM and XRD. Thirty-four minerals were identified by XRD, many of which were detrital. Secondary precipitates on the surface of detrital minerals were revealed by the SEM; of these only the sulphides were found to contain detectable levels of heavy metals. Eleven minerals were identified in the 'Biofloc', of which most were clays. The fractionation scheme defined 2 fractions that could hold heavy metals by complexation. The 'Soluble' had a CEC of 8.8 meq/gm and the 'Biofloc' 4 meq/gm. Complexation by the heavy metals and a few other important cations was measured. A thermodynamic model was built which describes the possible solution species, mineral phases and complexation by the biomass in terms of a set of 33 primary components. This model was solved by computer for an 'average' sludge based on published analyses, and considered 313 solution species, 42 exchange reactions and 129 possible minerals. The predicted speciation was broadly in line with observations and suggested that the majority of the heavy metals separating with the 'Biofloc' would have been held as fine enmeshed sulphide precipitates. The model may be used with existing programs such as MINEQL and GEOCHEM. Preliminary studies have shown that with a few additions the model may be used to describe the heavy metals in sludged soil.

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Chan, Sai Yen Victor, et 陳世欽. « Potential environmental hazards of wastewater from hospitals and theirmitigation ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B41016257.

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Anand, Archana. « The nitrogen isotope fingerprint of wastewater effluents in Hong Kong ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/207619.

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Nitrogen pollution in marine waters is directly tied to human development – including agricultural runoff, atmospheric deposition, and urban wastewater effluents. After more than a century of urbanization, Hong Kong faces a major challenge in mitigating marine pollution, particularly nitrogen. Indeed, nitrogen pollution may be one of the primary causes of benthic ecosystem decline as evidenced by a contraction in the historical distribution of corals and seagrasses. Such ecosystems provide vital ecosystem services, not limited to nursery grounds for economically important fisheries. While the Hong Kong Government (HK Environmental Protection Department) has established long-term monitoring of marine nitrogen concentrations, the data obtained on the size of the total nitrogen pool does not indicate the proportion of which is derived from human activities. Stable isotope analysis of nitrogen (δ15N) can provide more accurate information on the source of nitrogen not only in the receiving environment but also in the marine and benthic organisms present. This project critically examines Hong Kong’s nitrogen sources from sewage effluents using stable isotope analysis. Objectives were to investigate (1) the δ15N of sewage effluents sampled across Hong Kong, Kowloon, New Territories, Lantau and Outlying Islands (2) the differences in δ15N across sewage treatment type and (3) the differences in δ15N between the wet and dry seasons with the aim of developing a new approach for detecting and mapping sewage impacts in Hong Kong. Through a 6-month sampling effort across 18 sewage treatment facilities, this study shows that 70% of δ15N values obtained from the sewage effluents were characteristically enriched (δ15N values up to 205 ‰) when compared with naturally occurring nitrogen sources in the biosphere (I10‰ < δ15N < 10‰). Overall, δ15N was more variable in plants with preliminary treatment and chemically enhanced primary treatment (CEPT) than in plants with primary, secondary or tertiary treatment. The mean daily flow rate explained 75.7% of the observed variability in δ15N values of preliminary treatment plants and 85% of the variability in primary treatment plants. This was also the case in plants having CEPT with a negative correlation of 46% between mean daily flow rate and sewage effluent δ15N values. This suggests varying models for the quantity and retention time of wastewater versus δ15N signatures for different treatment types that require further study. Microbial activity by aerobic bacteria and protozoa, ammonia volatilization and the amount of nitrogen present in the effluents are possible causes for δ15N enrichment. Enterococcus counts of three sites sampled indicated that that the municipal sewer system and wastewater treatment plant in Stonecutters Island (56,100 CFU 100 mlI1) and preliminary treatment facilities (57,800 CFU 100 mlI1) in Hong Kong Island are insufficient in preventing bacterial contamination in comparison to US EPA standards for recreational use of coastal marine waters (35 CFU 100 mlI1). These findings indicate that enriched δ15N values directly translate to the presence of anthropogenic inputs and that monitoring δ15N of primary producers is a feasible and important tool for monitoring wastewater management in Hong Kong.
published_or_final_version
Environmental Management
Master
Master of Science in Environmental Management

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Visser, Gunnar Lieb. « Permeable reaction barrier system for the treatment of textile wastewater using cobalt oxide ». Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2631.

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Thesis (MEng (Chemical Engineering))--Cape Peninsula University of Technology, 2018.
Advanced oxidation processes (AOPs) have gained considerable interest in the wastewater treatment industry. Low selectivity to organic pollutants and the high oxidation potentials provided by the free radicals produced from these processes are the root of this interest. Hydroxyl radical based AOPs seemed to dominate the field but recently sulphate radical based AOPs started to become more popular due to their even higher oxidation potential. The textile industry is known to be a considerable contributor to wastewater production. Many pollutants in this wastewater are organic pollutants which are very persistent to the more traditional treatment processes such as biological treatment and membrane filtration. Numerous studies have shown the potential and success of catalytic AOPs for the degradation of organic pollutants in wastewater. One such process is the use of a cobalt oxide nano-catalyst in conjunction with a peroxymonosulfate (PMS) oxidizer (Co3O4/PMS). The shortcoming with nano-catalysts however are the difficulty of recovering the catalyst in a slurry system or the effective immobilization of the catalyst in a continuous system. To address the issue of nano-catalyst immobilization, two different methods were used in the study to effectively immobilize the catalyst in a substrate. The methods were compared by utilizing the permeable reaction barriers in a continuous flow reactor. A bench scale reactor of 2.4 L/hr was designed and used to study the effect of PMS, catalyst mass and flow rate on the degradation efficiency and to determine the residence time and catalyst per PRB cross-sectional area ratio. A scale up rationale was formulated based on a constant residence time and the catalyst mass per PRB cross-sectional area ratio. Two design correlations were developed to predict the size of the permeable barrier and the catalyst mass required for the scale up PRB system. These parameters were used to design a reactor 30 times that of the bench scale reactor. In both reactors the optimum degradation occurred within 2 minutes indicating the success for catalyst immobilization and the development of a continuous reactor utilizing the Co3O4/PMS advanced oxidation technology.

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Chiu, Chen. « Anaerobic digestion of baker's yeast wastewater using a UASB reactor and a hybrid UASB reactor ». Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29589.

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The start-up and step-up operation of two 16-liter, continuously operated, upflow anaerobic reactors receiving baker's yeast wastewater is presented in this thesis. The two reactors (A and B) were almost identical in construction. Reactor A was a conventional upflow anaerobic sludge blanket (UASB) reactor, and reactor B was a hybrid reactor. In addition to all the features of a UASB reactor, a fixed-film structure was installed in the mid section of the reactor B. Both reactors were operated at 35 °C and at a constant hydraulic retention time of 7 days. The waste strength, expressed in chemical oxygen demand (COD), was varied from 8 g COD liter⁻¹ (during the start-up) to 58 g COD liter⁻¹. The organic loading rate ranged from 1.1 to 9.4 g COD liter⁻¹ day⁻¹. The start-up lasted for the first 46 days. Towards the end of the start-up, methane production rates of 0.23 and 0.28 liter CH₄ liter⁻¹ day⁻¹ and COD reductions of 62.2% and 67.2% were achieved at organic loading rates of 1.1 and 1.3 g COD liter⁻¹ day⁻¹ for reactors A and B respectively. During the step-up operation, maximum methane production rates were, for reactors A and B respectively, 0.91 and 0.95 liter CH₄ liter⁻¹ day⁻¹ at organic loading rates of 5.8 and 6.4 g COD liter⁻¹ day⁻¹. In addition, reactor profiles for sludge concentration, pH, volatile fatty acids, and COD are also presented.
Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate

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DeBruyn, Adrian M. H. « Sewage and the ecology of the St. Lawrence River ». Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38176.

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This thesis examines the ecological consequences of sewage disposal in aquatic ecosystems. Sewage simultaneously represents a form of enrichment and a source of stress to a receiving system. Enrichment effects dominate when sewage loading does not exceed the capacity of the system to assimilate waste, as is presently the case in the St. Lawrence River. We developed a method to quantify the assimilation of sewage-derived organic matter by riverine biota, then used this method to examine the pathways by which sewage enhances secondary production in the St. Lawrence. We showed that the relative importance of dissolved nutrients and particulate organic matter to the river food web is to a large degree dictated by the physical and biological characteristics of the local environment. The effects of this enrichment on the receiving water community were also influenced by habitat characteristics. Analysis of body size distributions revealed that only the largest organisms had higher densities at enriched sites, and that the identity of these organisms depended on habitat structure. Densities of smaller organisms were controlled by a combination of habitat characteristics and feeding interactions. This pattern was consistent with food web models of top-down (consumer) control. At each trophic level, relatively invulnerable (large) prey achieved higher densities, whereas densities of more vulnerable (small) prey were controlled by their predators. Finally, we synthesized the ideas outlined above to predict how conditions in the St. Lawrence will change in the future as a result of lower water levels. More extensive macrophyte cover, slower current, and warmer temperatures in a shallower St. Lawrence will all enhance the ability of the system to physically retain and biologically process sewage nutrients, but will also increase the likelihood of negative effects such as anoxia.

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Pardieck, Daniel L. « Biodegradation of phenols in aquatic culture by soil-derived microorganisms, with reference to their fate in the subsurface ». Diss., The University of Arizona, 1988. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1988_226_sip1_w.pdf&type=application/pdf.

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Takwi, Colette Nchong. « An assessment of the management of odour at the Athlone wastewater treatment works, Cape Town ». Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2788.

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Thesis (MTech (Environmental Management))--Cape Peninsula University of Technology, 2017.
¹Odour nuisance is increasingly becoming one of the major environmental problems in various countries across the world, especially odour associated with wastewater (Alfonsin et al., 2015; Schlegelmilch et al., 2005; Gostelow et al., 2001). As a result, the management of odour from Wastewater Treatment Works (WWTW) has become one of the environmental challenges besetting these facilities in recent times. The dispersion of odour across the physical boundary of wastewater treatment facilities presents not only negative environmental impacts to the natural environment, but also constitute a nuisance to surrounding populations. The Athlone (WWTW) located in the urban City of Cape Town with high demographics and adjacent to sensitive communities is thus not immune to poor air quality associated with WWTW activities (Walton, 2005). The population growth due to rural-urban migration has further put severe pressure on the facility and thus worsening the odour problem in the area. As a result, complaints have been received by the City Council from the surrounding communities over the last 20 years. In response to these complaints, the management of the WWTW introduced an odour management system with a particular focus on the use of a biotrickling filter coupled with the use of odour masking sprays. This management intervention was adopted in order to control the odour emitted to the atmosphere from the facility (WWTW). While these measures are said to reduce the prevalence of odour to the surrounding environment, it was, however, not clear whether or not such management interventions have reduced odour emitted from the treatment plant. This research was premised on two postulations as an approach to analyse the effect of the odour management plan adopted by the Athlone WWTW’s management and these are: 1) the perceived experience of odour by the adjacent neighbouring communities and, 2) the understanding of the inherent atmospheric dynamics (such as wind velocity, atmospheric stability, inversion layer and ventilation) which influence odour dispersal in the area. The research project argues that these two factors should be taken into account to ensure that the management of odour is sustainable. It is within this background that the research aimed at assessing the management of odour at the Athlone WWTW and to find out, if at all, the inherent local atmospheric conditions in the area and views of the surrounding communities are incorporated into the management of odour from the plant. The methodological design adopted in the study was case study approach. However, the atmospheric data (wind speed and direction) was obtained from the South African Weather Service (SAWS). These variables were analysed qualitatively and experimentally by the use of wind diagrams to provide insight on 2atmospheric stability conditions, surface inversion and topographical properties, and how these phenomenon influences odour dispersion. The study also reviewed previous odour management reports produced by the Althone WWTW management. This type of data was finally supported by data collected from the community by means of a community survey, face-to-face in-depth interviews and qualitative observation. Some major findings from the study revealed that the local weather of Athlone influences the dispersion of odour – facilitating dispersion in the summer through high wind velocities, while impeding dispersion during winter due to the presence of atmospheric stability conditions. Prevailing odours in this community has led to a general feeling of displeasure amongst community members especially since the management of the treatment plan does not include the local community in the decision-making process. In spite of these, the facility’s management approach was found to be more of a response driven nature even though it is ranked as a high-risk facility.

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Keita, Abdoulaye. « The relative ecological effectiveness and economic efficiency of four wastewater treatment plants in East Central Indiana ». Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1177978.

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The study was conducted to investigate the ecological effectiveness and economicefficiency of four wastewater treatment plants in East Central Indiana (Muncie, Anderson, Alexandria, and Paws). Data were collected from the four plants, then analyzed descriptively and statistically, and compared in terms of ecological effectiveness and economic efficiency. The Muncie, Anderson, and Paws wastewater treatment facilities were not significantly different from one another in terms of biochemical oxygen demand (BOD5) reductions, but each reduced BOD5 more than the Alexandria facility over the three- year period (1996, 1997, and 1998). Plants were not statistically different regarding suspended solids (SS) reductions. The Muncie, Anderson, and Paws wastewater treatment plants were also not significantly different from one another on ammonia reduction, but each plant reduced ammonia significantly more than Alexandria. Muncie and Anderson were not different from each other on dissolved oxygen (DO) levels, but each had a statistically higher level of DO in the final effluent than Alexandria and Paws. The study showed a statistically significant difference in fecal coliform bacteria abatement between Anderson and Alexandria, Anderson and Paws, and Muncie and Alexandria. Furthermore, Muncie, Anderson and Alexandria were different in terms of cost per 1000 gallons of wastewater treated. Muncie has been treating wastewater at a lower cost than the other treatment plants, whereas Anderson had a higher cost over the three-year period.
Department of Natural Resources and Environmental Management

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Lucero, Daniel William. « Plant and soil effects from the surface application of poultry litter to unmanaged pasture ». Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06112009-063243/.

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Uggetti, Enrica. « Sewage sludge treatment in constructed wetlands : technical, economic and environmental aspects applied to small communities of the mediterranean region ». Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/51580.

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During the last years, the implementation of new Wastewater Treatment Plants has lead to a significant increase of sludge production. As a response, sludge valorisation in agriculture is the preferred option nowadays, ensuring the return of organic constituents, nutrients and microelements to crop fields. In practice, sludge treatments should provide a final product suitable for land application, with reasonable investment as well as operational and maintenance costs. In this sense, sludge treatment wetlands (STW) appear as a suitable technology for sludge management from an economic and environmental point of view. The main objective of this research work was to assess the suitability of STW for sludge management; with special focus on small communities of the Mediterranean Region. To this end, technical, environmental and economic aspects of the treatment were studied in 3 full-scale systems and in a pilot plant located in Catalonia. A comparison with conventional treatments for sludge management is presented in order to establish the most favourable solution for the Catalan context. As the final result from this work, design and operation criteria are proposed as a guide for STW implementation in small Mediterranean communities. The study of the performance of the full-scale STW suggests good treatment efficiency. Moisture content was reduced by 16-30%, reaching efficiencies similar to those of conventional dewatering technologies. On the other hand, VS were reduced up to 30-49%VS/TS, suggesting the progressive sludge stabilisation and mineralisation. Similar values were found at the end of the treatment in the pilot plant. In this case the sludge volume was reduced around 80% and TS increased up to 16-24%. However, the observed VS reduction (up to 50%VS/TS) after 2 months without feeding, indicates that longer resting periods should be applied in order to increase mineralisation of the sludge. A finite element model able to simulate sludge dewatering in STW was developed by combining the evapotranspiration (ET) and the Terzaghi¿s consolidation theory representing water percolation. The model allows for the determination of the most appropriate feeding frequency as a function of the sludge height stored on the wetland. Similarly, the sludge loading rate is determined as a function of ET, feeding frequency and sludge height. On the whole, the model implemented is a useful tool for the establishment of standardised criteria of STW operation. The characterisation of the final product from the pilot plant and from three full-scale systems demonstrated the suitability of biosolids as organic fertilisers. DRI values indicated the partial stabilisation of the product. Moreover, the absence of phytotoxicity and the heavy metals concentrations below the legal thresholds confirmed their viability to be reused in agriculture. However, in the pilot plant, pathogens were still present after 2 resting months, confirming the necessity of a longer resting period. Monitoring the stabilisation degree as phytotoxicity, heavy metals and pathogens' concentration during the final resting period would help optimising its duration. Looking at the environmental aspects, the static chamber method was successfully adapted to the determination of gas emissions from STW. Aerobic conditions before sludge feeding, characterised by low methane emissions and high nitrous oxide emissions, were strongly altered by fresh sludge feeding, which increases CH4 emissions and reduces N2O emissions. According to the measured emissions, the Global warming potential of STW corresponds to 17kgCO2eq/PE¿y, which is from 2 to 9 times lower than that of sludge centrifugation and transport. Besides,the economic and environmental assessment indicates STW with direct land application as the most cost-effective technique, which is also characterised by the lowest environmental impact.Thus STW are the best solution to manage waste sludge in decentralised small communities.

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Myburgh, Dirk Petrus. « The treatment of biodiesel wastewater using an integrated electrochemical and adsorption process ». Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2693.

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Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2018.
The production of biodiesel is an energy and water intensive process. The wastewater that is produced during this process is high in concentrations of COD, BOD, FOG and various other contaminants. Since it contains low levels of nutrients, it is difficult to degrade using natural processes such as conventional activated sludge wastewater treatment. The discharge of untreated biodiesel wastewater also raises serious environmental concern. It interferes when remediated with biological processes and results in additional costs during the production of biodiesel when penalties and fines are applied. Conventional treatment processes are not capable of treating contaminants and pollutants in biodiesel to satisfactory concentrations and hence advanced treatment processes are necessary. In this research, a lab scale integrated treatment process was used to investigate the successful reduction of contaminants, in particular COD, BOD and FOG. The integrated treatment process used in this study consisted of three consecutive steps; acidification, electrochemical oxidation and adsorption using chitosan as an adsorbent. The electrochemical oxidation process with IrO2-Ta2O5/Ti anodes was applied to treat biodiesel wastewater. Different operating conditions were tested to establish favourable conditions. The current density applied as well as the concentration of NaCl as the supporting electrolyte greatly affected the process. A NaCl concentration of 0.08M was deemed sufficient, whereas a current density of 1 mA/cm² showed superior performance compared to lower or higher current densities. Adsorption of pollutants in biodiesel wastewater was investigated using Chitosan as the adsorbent. Various chitosan concentrations, initial pH of the wastewater and repetitive adsorption stages were investigated. It was discovered that all three operating conditions greatly affect the performance of the process. The three consecutive adsorption stages using a chitosan concentration of 4.5 g/L at a pH of 2 resulted in the highest pollutant removal. It was observed that the integrated treatment process could reduce COD, BOD and FOG levels by 94%, 86% and 95% respectively. This concludes that the treated effluent complies with local industrial effluent discharge standards, which could be disposed safely without further treatment.

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Boshoff, Genevieve Ann. « Development of integrated biological processing for the biodesalination of sulphate- and metal-rich wastewaters ». Thesis, Rhodes University, 1999. http://hdl.handle.net/10962/d1003958.

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The substantial pollution threat to the South African environment from acid mine drainage (AMD) effluents has been well documented. Due to the juvenile nature of acidity in these flows, any remediation strategies implemented will need to function effectively and at low cost for long periods of time. The widespread use of sulphate reducing biological systems for the treatment of such effluents, and in particular large volume flows, has been limited. The supply of inexpensive electron donor and carbon sources, as well as appropriate reactor designs capable of handling large volume flows, have been identified as among the principal factors limiting development of this technology. The broad aim of the research programme reported here was to undertake an evaluation of the feasibility of an algal-bacterial integrated ponding system for the treatment of AMD, and the waste stabilisation pond (WSP) as an appropriate reactor design for this application. The study attempted to demonstrate the feasibility of individual unit operations in a proposed process train using complex organic carbon serving as the electron donor source for the sulphate reducing bacteria (SRB). Studies were undertaken as laboratory and pilot-scale investigations. Tannery effluent was shown to be a functional carbon source for biological sulphate reduction, with effective removal of sulphate and organics being recorded. In turn, the use of biological sulphate reduction for the treatment of tannery effluent was demonstrated. Algal biomass was shown in laboratory studies to function as an effective carbon source for biological sulphate reduction. It is known that micro-algae produce large quantities of photosynthate which is released to the growth medium under conditions of physiological stress. The potential for the use of photosynthate production in high rate algal ponding systems and its manipulation and use as a sustainable carbon source for sulphate reduction was investigated. Growth of a mixed culture of Dunaliella under conditions of light, temperature and salinity stress demonstrated production of large quantities of organic carbon. However, growth was inhibited at high temperatures. An elevation of salinity levels led to a decrease in growth of Dunaliella, but to increased organic carbon production. Spirulina spp., on the other hand, grew well at higher temperatures but showed the highest organic carbon production, and release to the medium, under low light conditions. These results led to a proposed process for the integration of algal ponding into an integrated system for the treatment of AMD. The algal biomass may be fed into the anaerobic digester as a carbon source, or it may be passed into a High Rate Algal Pond (HRAP) where it is stressed to enhance the organic carbon content. This can then be fed into the anaerobic digester as a carbon source. The impact of high levels of sulphide in the water feeding to the algal growth compartment was investigated. Spirulina spp. isolated from a tannery waste stabilisation pond was shown to be a sulphidophilic strain of cyanobacterium, capable of being adapted to high concentrations of sulphide. Dunaliella salina on the other hand was less tolerant. These results demonstrated the practical use of algal biomass providing an oxygen-rich cap for odour control on the surface of the facultative pond as well for the secondary treatment of sulphide-rich overflow to the High Rate Algal Pond. The ability of micro-algae to elevate the pH of their surrounding environment was evaluated as a functional precipitant and neutralisation reagent for acidic metal containing wastewater. Spirulina spp. was shown to perform effectively. D. salina was less functional in this environment. Anacystis spp. was effective in elevating the pH of a defined medium as well as a zinc-rich effluent. These results indicated the practicality of a neutralising function for algal ponds in the treatment of AMD. Metal removal in the system was found to be a combined function of sulphide precipitation, removal by binding to micro-algal biomass and extracellular polymeric substances. The feasibility of waste stabilisation ponding technology use for the treatment of large volume AMD effluents was provisionally demonstrated. It was shown that complex carbon sources would be used as efficient electron donors for sulphate reduction. The integration of algal ponding into the system provides for the generation of a sustainable carbon source, odour control with the recycling of oxygen-rich water onto the top of the facultative pond, secondary treatment of the anaerobic digester overflow, and the neutralisation of the incoming acidic effluents and removal of heavy metals. Integration of the individual unit operations, the feasibility of which has been provisionally demonstrated in this study, into a continuous process train is being investigated in follow-upstudies.

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Shrivastava, Vikram. « Creek water quality impacts : irrigation tailwaters and sewage discharges ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0006/MQ44277.pdf.

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Kan, Hon-shing, et 簡漢成. « EIA of sewerage projects : an overview of the Hong Kong situation ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31253155.

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Fortin, Nathalie. « Molecular characterization of dechlorination potential in kraft pulp mill effluent treatment systems ». Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27317.

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Many low molecular weight chlorinated organic compounds produced by the pulp and paper industry during kraft bleaching of the wood pulp are toxic. Mass balance studies suggest that mineralization of chlorinated organics is occurring in pulp and paper mill wastewater treatment systems. To understand the nature of dechlorination activity, molecular tools such as oligonucleotide primers and corresponding DNA probes were developed to monitor the presence of microorganisms possessing key genes (dehalogenases) responsible for the degradation of chloroaliphatic organics in kraft pulp mill effluent treatment systems. Oligonucleotide primers designed from the coding sequence of known dehalogenases and a methane monooxygenase gene, which is known to catalyze dehalogenation reactions, were used for polymerase chain reaction (PCR) analysis, using genomic DNA extracted from dehalogenating bacterial isolates and total community DNA extracted from water and sediments of lagoon treatment systems. PCR amplification with dhlB oligonucleotide primers, designed from the haloacid dehalogenase of Xanthobacter autotrophicus, revealed the presence of dehalogenase genes in both aerated lagoons and stabilization basins. Similar results were obtained with mmoX primers designed from the methane monooxygenase gene of Methylococcus capsulatus. DNA sequence analysis of several PCR fragments showed significant similarity to known dehalogenase genes. The molecular tools developed in this study revealed the presence of different types of microorganisms with dechlorination potential in the microbial community of pulp mill effluents.

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Bhathena, Jasmine. « The physical and physiological effects of nitrogen and phosphorus limitation on a pulp and paper mill effluent biotreatment microbial community / ». Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80228.

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The influence of nitrogen (N) and phosphorus (P) limitation on pulp and paper mill activated sludge (AS) floc properties was studied using a bioreactor fed with synthetic Kraft mill effluent. The bioreactor and synthetic effluent were designed and shown to perform like the real mill system providing the AS, establishing the in vivo relevance of the results. Limitation of either N or P produced inadequate effluent biotreatment, shown by poor BOD5 and suspended solids removal, and by decreased biomass health, performance, and floc settling. Greatly enhanced poly-beta-hydroxybutyrate (PHB) (but not carbohydrate or extracellular polymeric substances [EPS]) synthesis was the common response of the floc microbial community to N limitation over many days. In contrast, P-limitation increased total carbohydrate and EPS, but not PHB.
N limitation, but not P limitation, caused the net floc surface charge to be much more negative, while P-limitation, but not N-limitation, increased the floc bound water content and surface hydrophobicity. Thus, in real pulp and paper mill AS systems, careful manipulation of N or P additions may be useful to optimize the key process of charged polymer-assisted AS dewatering.

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Renew, Jay Earl. « Novel analytical method development and fate assessment for fluoroquinolone, sulfonamide and trimethoprim antibiotics in engineered water treatment systems ». Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/19910.

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Larsson, Josefine. « Genetic Aspects of Environmental Disturbances in Marine Ecosystems : Studies of the Blue Mussel in the Baltic Sea ». Doctoral thesis, Södertörns högskola, Miljövetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-33697.

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Anthropogenic environmental changes can serve as drivers for evolutionary responses in wild populations. To predict the long-term impact of anthropogenic changes on populations, it is crucial to understand the genetic effects caused by these disturbances. The Baltic Sea is considered to be one of the world’s most contaminated seas, and the increase of anthropogenic chemical pollution is a major threat to its ecosystems. This thesis assesses the impact of harbors and sewage treatment plants on physiological traits and genetic structure of resident populations of blue mussels at replicated sites in the Baltic Sea. The initial evaluation of the overall genetic pattern in blue mussel populations in the Swedish West Coast, the Baltic Proper and the Bothnian Sea found genetic differentiation between the three water basins and a low genetic differentiation within each basin, especially within the Baltic Proper. Despite the low genetic differentiation among blue mussels within the Baltic Proper, a parallel genetic differentiation associated with sewage treatment plant effluents was found in this basin. This included genomic regions with a high degree of differentiation between reference sites and sites affected by sewage plants effluent. This genetic differentiation is suggested to be due to post-dispersal selection acting in each generation. In contrast, no parallel genetic differentiation was associated with harbors. We identified five genomic regions in blue mussels, showing strong signs of selection, shared among three out of four replicated reference sites and sites affected by sewage effluents in the Baltic Proper i.e. Askö, Tvärminne and Karlskrona. An initial characterization of these genomic regions revealed functions related to immune and endocrine responses, oxidative stress and shell formation. Our results indicate that selection caused by sewage effluents involves multiple loci. The same genomic regions are found across different locations in the Baltic Proper but there are also unique genomic regions at each location. No genotoxic or histopathological effects were found among blue mussels from sewage effluent-affected areas but a higher frequency of histological abnormalities in the digestive gland were observed in mussels from harbors.
Evolutionära anpassningar till miljöstörningar i marina ekosystem: genetisk ekotoxikologi i Östersjön

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Fappi, Devanir André. « Micro e ultrafiltração como pós-tratamento para reúso de efluentes de abatedouro e frigorífico de suínos ». Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1273.

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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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Wilson, Cullen. « Biogeochemical Effects of Lime-Treated Biosolids Amendments on Soils in a Northeastern Forested Ecosystem ». Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/WilsonC2008.pdf.

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Williams, Margot Lluttrell. « Macroinvertebrate community and species responses to chlorinated sewage effluent in the Umsunduze and Umbilo rivers, Kwa Zulu-Natal, South Africa ». Thesis, Rhodes University, 1997. http://hdl.handle.net/10962/d1005413.

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Chlorine has a wide variety of applications in water treatment. Because of its disinfectant efficacy, it is used world wide for the treatment of potable water, sewage, swimming pools and for the control of nuisance organisms in cooling towers. A problem arises when such chlorinated water enters the natural environment, as chlorine's greatest advantage, i.e. its germicidal capacity, becomes its greatest disadvantage. In particular, the discharge of heated, chlorinated water from cooling towers and chlorinated, treated sewage into rivers have severe consequences for the riverine flora and fauna. This study focused on the effects of chlorinated, treated sewage effluent on the community structure of benthic macroinvertebrates in two rivers in KwaZulu-Natal viz. the Umsunduze River in the Pietermaritzburg area, and the Umbilo River in the Durban area. The study was conducted in three phases. The first two phases comprised a toxicological investigation of the effects of chlorine on a selected riverine macroinvertebrate, and the third phase comprised an ecotoxicological investigation of the effects of chlorinated treated sewage on benthic macroinvertebrate community structure. The first phase of the study involved the development of an artificial stream system which would be suitable for determining the response of a selected macroinvertebrate species to chlorine. Chlorine is both reactive and volatile, so this necessitated the development of a specialised flow-through system with apparatus which would allow continuous dosing of a sodium hypochlorite solution. The system was set up at the Process Evaluation Facility at Wiggins Waterworks, Durban, where raw water from lnanda Dam was used. The second phase involved the use of this artificial stream system to conduct acute 96 h toxicity tests. Baetid mayfly nymphs (Baetis harrisoni Barnard) were selected as the test organisms after a preliminary investigation found them to be suitable for survival under laboratory conditions. For comparative purposes, tests were run first on B. harrisoni from a relatively uncontaminated stream in a residential area of Westville, then on specimens from the severely impacted Umbilo River. The LC₅₀ of chlorine for organisms from both sources was found to be in the region of 0.004 mg/l (free chlorine). This value was well below the general effluent standard of 0.1 mg/l in effect at the time. The recommended acute environmental guideline is 0.001 mg/l. The third phase of the study involved field validation of the toxicity test results. It was hypothesised that since the LC₅₀ for free chlorine was 0.004 mg/l, B. harrisoni would not be found downstream from a point source of chlorinated effluent where the concentration of free chlorine ranged from 0.06 to 0.2 mg/l, and that the macroinvertebrate community structure would also be altered. In order to test these hypotheses, benthic macro invertebrate community structure was investigated at several sites up- and downstream from the outlets of the Darvill Wastewater Works in the Umsunduze River and the Umbilo Sewage Purification Works in the Umbilo River. In addition, in order to differentiate between the effects of chlorinated and unchlorinated treated sewage, a section of the Umbilo River (upstream from the chlorinated discharge) was exposed to unchlorinated, treated sewage. In this way, a limited "before and after" sewage and an "upstream and downstream" from sewage investigation could be carried out. Organisms were collected from riffles (and from pools in the Umbilo River) and the samples were then sorted and organisms were identified to species level, where possible, otherwise to genus or family. Changes in community composition were shown graphically as pie charts of relative proportions of organisms found at each site, graphs of the average number of taxa at each site; and graphs of the average number of individuals at each site; Data from the Umbilo River were also analysed using TWINSPAN (Two-way indicator species analysis). In both the Umsunduze and the Umbilo rivers, the deleterious effects of the chlorinated effluent were clearly evident. At Umsunduze Site 3 and Umbilo Site 5 (both immediately downstream from the chlorinated effluent) both the number of taxa and number of individuals were substantially reduced, sometimes to zero. Where organisms were found at the next sites downstream (Sites 4 and 6 respectively), the samples were dominated by Chironomus. In contrast, the unchlorinated effluent in the Umbilo River caused very little difference in community structure. As predicted, B. harrisoni was not found in downstream samples in which chlorine was present, yet appeared to be relatively unaffected by the unchlorinated effluent, suggesting that chlorine, rather than the effluent was responsible for its absence at downstream sites. In conclusion, it would appear that while treated sewage effluent certainly causes changes in macroinvertebrate community structure, chlorination of this effluent leads to large scale destruction of the riverine community. This in turn delays the recovery process of the river, rendering a longer stretch unfit for use. The consequences of this delayed recovery are that the failure to meet the water quality requirements of the natural environment results in those of the other water users (agriculture, industry, domestic and recreation) not being met. This reduces the natural capacity of the riverine community to process organic waste and recover from the discharge of sewage effluent. Chlorination increases the distance of impaired water quality and environmental integrity which result from organically enriched treated sewage effluent. The results of the study indicated that the draft water quality guidelines for aquatic ecosystems, derived from inadequate data, and calculated with a safety factor, were the correct order of magnitude. The approach followed in the study will be useful in the development and refinement of water quality guidelines for aquatic ecosystems.

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Jingxi, Estella Zandile. « Forward osmosis : a desalination technology for the textile industry ». Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2674.

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Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2017.
Similar to the energy crisis, the critical state of the water supply in South Africa (SA) is a combination of (i) resource exhaustion and pollution; (ii) increasing demand; and (iii) poor infrastructure. Despite its importance, water is the most poorly managed resource in the world. The disposal of industrial effluents contributes greatly to the poor quality of water. The textile industry consumes great quantities of water and produces enormous volumes of wastewater which requires appropriate treatment before being released into the environment. In an attempt to address the water issues, research globally has focused on advanced technologies such as desalination to increase limited pure water resources. The need for alternative desalination methods for the production of clean water from alternative water resources, such as seawater and brackish water, has gained worldwide attention. Reverse osmosis (RO) and Nanofiltration (NF) have been used as unswerving approaches to yield freshwater. Forward osmosis (FO) is a developing membrane technology that has increased substantial attention as a possible lower-energy desalination technology. However, challenges such as suitable FO membranes, membrane fouling, concentration polarisation, and the availability of effective draw solutions (DS), limit FO technology. FO is seeking more importance in novel areas where separation and recovery of the DS is not required. The aims of this study was to: i) identify alternative water resources and evaluate their potential as suitable feed solution (FS); ii) Identify dyes and evaluate their potential as suitable draw solutions (DS) at different concentrations; iii) assess the use of aquaporin biomimetic membrane and iv) assess a FO system for the production of dye solutions. Osmotic pressure (OP) is the pressure exerted by the flow of water through semi-permeable membrane, separating two solutions with different concentrations of solute. The DS should always have OP higher than the FS in order to achieve high water flux. Three basic dyes (i.e. Maxilon Turquoise, Red and Blue) and three reactive dyes (i.e. Carmine, Olive Green and Black) were selected, based on their common use in the SA textile industry. The respective dye samples were prepared at different concentrations and dye-to-salt mass ratios ranging from 1:10 to 1:60 and assessed for OP using a freezing point osmometer. A lab-scale FO unit was used for all the studies. Feed and draw channels were circulated in a counter-current flow at a volumetric flow rate of 600 mL/min. Feed solutions(FS) included deionised water (DI) as a control, brackish water (BW), synthetic seawater (SSW) and textile wastewater (TWW) collected from two textile factories. OP of the FS (DI, BW5, SSW and SW, Factory 1 and Factory 2) was 0, 414, 2761, 2579, 1505 and 3308 kPa, respectively. Basic Blue and Reactive Black generated a higher OP compared to other selected dyes in the study and were therefore selected to be used as DS at a 1:10 dye-to-salt ratio and 0.02 M concentration. An aquaporin biomimetic FO membrane (Aquaporin, Denmark) was used for all the experiments conducted in the FO mode.

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Norwood, Sasha Norien. « Characterization of Nano-scale Aluminum Oxide Transport Through Porous Media ». PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/981.

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Land application of biosolids has become common practice in the United States as an alternative to industrial fertilizers. Although nutrient rich, biosolids have been found to contain high concentrations of emerging contaminants (e.g. pharmaceuticals, personal care products) while containing a significant fraction of inorganic nano-scale colloidal materials such as oxides of iron, titanium, and aluminum. Given their reactivity and small size, there are many questions concerning the potential migration of these nano-sized colloidal materials through the soil column and into our surface and groundwater bodies. Transport of emerging pollutants of concern through the soil column, at minimum, is impacted by colloidal properties (e.g. chemical composition, shape, aggregation kinetics), solution chemistry (e.g. pH, ionic strength, natural organic matter), and water flow velocity. The purpose of this current research was to characterize the long-term transport behavior of aluminum oxide nanoparticles (Al2O3) through a natural porous media with changes in pH, aqueous-phase concentration, pore-water velocity and electrolyte valence. Additionally, deposition rates during the initial stages of deposition were compared to several models developed based on colloid filtration theory and DLVO stability theory. Benchtop column laboratory experiments showed that, under environmentally relevant groundwater conditions, Al2O3 nanoparticles are mobile through saturated porous media. Mobility increased under conditions in which the nanoparticles and porous media were of like charge (pH 9). Changes in linear pore water velocity, under these same high pH conditions, showed similar transport behavior with little mass retained in the system. Deposition is believed to be kinetically controlled at pH 9, as evidenced by the slightly earlier breakthrough as flow rate increased and was further supported by observed concentration effects on the arrival wave following several stop flows. While lower aqueous-phase concentrations resulted in significantly longer breakthrough times, the total mass retained in the system was found to be independent of concentration. Additionally, experimental deposition rate coefficients (kd), used to describe deposition kinetics under "clean bed" conditions, were similar across the aqueous-phase concentrations studied. The use of calcium chloride electrolyte solution in transport studies resulted in enhanced mobility relative to potassium chloride suggesting that changes in groundwater solution chemistry could impact mobility of contaminants associated with biosolids. Predicted deposition rate coefficients, using three different models, were found to under- or over-predict values relative to those experimentally determined values depending on the model. This current research has shown that nanocolloids associated with biosolids, specifically Al2O3, are mobile through saturated porous media. Given the ubiquity of nanocolloidal materials, particularly engineered nanomaterials, coupled with the expected increase in land-application of biosolids, a clear understanding of their transport and fate is prudent to understanding the potential impact these emerging pollutants may have on our surface and groundwater bodies.

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Geertsema, Wesley S. « Long-term effects of alum sludge application to land ». Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-12232009-020505/.

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Nelson, John D. « Toxicity characteristic leaching procedure analysis of dye containing sludges ». Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-10062009-020242/.

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Prinz, William Ernst. « The management and regulation of the beneficial use of sewage sludge as an agricultural soil amendment in Riverside County ». CSUSB ScholarWorks, 1996. https://scholarworks.lib.csusb.edu/etd-project/1190.

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Ma, Ruowei, et 馬若為. « Quantification and partition of perfluorochemicals in Hong Kong wastewater sludge ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43223862.

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Louis, Richard Joseph. « Utilization of a combined activated sludge fixed film media system for treatment of a high strength, high ammonia, industrial wastewater ». Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06112009-063901/.

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Ndobeni, Afika. « Effect of temperature and carbon to nitrogen ratio on the performance of an upflow anaerobic sludge blanket reactor treating sugarcane molasses ». Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2622.

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Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2018.
The sugar industry contributes to the development of the economy in many countries, including South Africa. The wastewater generated by this industry has a high pollution load, and therefore requires treatment before discharge to the environment. The primary aims of this study were to determine the performance of an upflow anaerobic sludge blanket (UASB) reactor treating sugarcane molasses and to develop an empirical model to predict the behaviour of the UASB in terms of chemical oxygen demand (COD) removal and biogas production. A UASB (46 L working volume) was inoculated with granular sludge from the brewery industry and was used to investigate the treatment of synthetic sugar industry wastewater with an average COD of 4101 mg/L. The experiments were designed using Design-Expert® Software Version 10. The analysis of variance for the models and the optimisation of reactor temperature and feed carbon to nitrogen (C/N ratio) were carried out using response surface methodology. The UASB was operated at constant hydraulic retention time and organic loading rate of 2.04 days and 2.01 kg/m3.d, respectively. A start-up period of 22 days was required to reach steady-state. The developed empirical models for total COD removal efficiency and biogas production rate were found to be statistically significant with Prob > F values of 0.0747 and 0.0495 and the determination coefficients (R2) were found to be 0.80 and 0.65, respectively. The optimal conditions were found to be at a temperature of 38oC and C/N ratio of 22 mgTOC/mgTN. The corresponding removal efficiencies in terms of total COD, five day biological oxygen demand, total nitrogen, total phosphorus, and sulphate was 77.7, 85.9, 99.2, 44.4 and 57.2%, respectively. Biogas was produced at a rate of 0.832 L/L.d with a methane, carbon dioxide and molecular oxygen content of 65.2, 32.8 and 0.6%. Results suggest that UASBs may offer a feasible option for reducing the organic strength of sugar industry wastewater, while simultaneously generating methane-rich biogas.

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Nzube, Silumko. « The accumulation of heavy metals in soil and vegetables irrigated with wastewater effluent in the Bauffalo City Region ». Thesis, Nelson Mandela Metropolitan University, 2014. http://hdl.handle.net/10948/d10207673.

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The present study was conducted to assess selected heavy metal levels (Cu, Fe, Zn, Ni and Pb) in soil and plants that are irrigated by mixed industrial and domestic wastewater in the Buffalo City region. Three types of samples were studied: soil, water and vegetables (spinach and beetroot). Soil analysis showed that most of the heavy metals were found to be acceptable within the SEPA limits. Most of the heavy metal concentrations found in the wastewater indicate that the water is not suitable for irrigation or for livestock use, according to guidelines from the Department of Water Affairs and Forestry of South Africa. The level of copper in the wastewater effluent exceeded the level specified by SEPA limits. In the wastewater the lead concentration averaged 3.24 and 1.98 ppm in Tshatshu (TS) and Mlakalaka (ML) respectively, which shows that both sites are not suitable for both irrigation and livestock usage. The heavy metal levels (Ni, Pb, and Cu) in both spinach and beetroot samples exceed the criteria specified by the WHO and SEPA standards. The study recommends terminating the usage of effluent for irrigation and further investigation or monitoring in these water sources.

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Halday, Ismail. « Study of the pathway of heavy metals in a sewerage system ». Thesis, Link to online version, 2007. http://hdl.handle.net/10019/389.

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Weggler-Beaton, Karin M. « The beneficial and detrimental effects of sewage sludge applications in South Australia ». Title page, contents and summary only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phw4113.pdf.

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Gauthier, Francis. « Study of coliform bacteria in Canadian pulp and paper mill water systems : their ecology and utility as health hazard indicators ». Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33401.

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Coliform bacteria have long been used to indicate fecal contamination of food, water, and solid surfaces, and thus the presence of a health hazard. In this study, the in-mill water and external effluent treatment systems of seven typical Canadian pulp and paper mills were shown to support the growth of numerous coliforms, especially Klebsiella spp, Escherichia coli, Enterobacter spp., and Citrobacter spp . Mill coliforms were shown to be not just simple transients from feedwater or furnish (wood), but to be continuously growing, especially in the primary clarifiers. Therefore, coliforms and fecal coliforms cannot be used as fecal contamination indicators in pulp and paper mill water and effluent treatment systems.
N2-fixing coliform populations were detected in mill water systems and were analyzed using N2-fixation assays and nitrogenase gene (nifH) probing. Both active in situ populations and cultured microbial isolates were tested. Active N2-fixation was demonstrated in six primary clarifiers. Measurement of the numbers and composition of the total culturable bacterial community in a primary clarifier revealed that approximately 50% of all aerobic cells contained nifH , of which >90% were Klebsiella. Coliforms growing on MacConkey agar plates from the primary clarifier were all identified as Klebsiella and 100% of these Klebsiella contained the nifH gene. Preliminary estimates indicate that the amount of N2 fixed per day is substantial in some clarifiers.

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Muller, Matthew Justin. « Linking institutional and ecological provisions for wastewater treatment discharge in a rural municipality, Eastern Cape, South Africa ». Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1013048.

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The Green Drop Certification Programme, launched in 2008 alongside the Blue Drop Certification Programme, aims to provide the Department of Water Affairs with a national overview of how municipalities and their individual wastewater treatment works (WWTW) are complying with licence conditions set by the National Water Act (NWA) (No. 36 of 1998; DWAF 1998) and the Water Services Act (No. 108 of 1997; DWAF 1998). By publishing the results of each municipality’s performance, the programme aims to ensure continuous improvement in the wastewater treatment sector through public pressure. The programme has been identified by this project as a necessary linking tool between the NWA and the Water Services Act to ensure protection and sustainable use of South Africa’s natural water resources. It does this through assisting municipalities to improve their wastewater treatment operations which in theory will lead to discharged effluent that is compliant with discharge licence conditions. These discharge licences form part of the NWA’s enforcement tool of Source Directed Controls (SDC) which help a water resource meet the ecological goals set for it as part of Resource Directed Measures (RDM). The link between meeting the required SDC and achieving the RDM goals has never been empirically tested. This project aimed to determine the present ecological condition of the Uie River, a tributary of the Sundays River which the Sundays River Valley Municipality (SRVM) discharges its domestic effluent into. It then determined whether the SRVM’s WWTW was complying with the General Standard licence conditions and what the impact of the effluent on the river was through the analysis of monthly biomonitoring, water chemistry and habitat data. Lastly, the project examined the effectiveness of the Green Drop Certification Programme in bringing about change in the SRVM’s wastewater treatment sector, which previously achieved a Green Drop score of 5.6 percent. It wanted to examine the underlying assumption that a WWTW which improves its Green Drop score will be discharging a better quality effluent that will help a water resource meets the RDM goals set for it. The Kirkwood WWTW did not have a discharge licence at the time of assessment and was thus assessed under the General Standard licence conditions. It was found that the Kirkwood WWTW was not complying with the General Standard discharge licence conditions in the Uie River. This was having a negative impact on the river health, mainly through high concentrations of Total Inorganic Nitrogen (TIN-N), orthophosphate and turbidity. The SRVM should see an improvement in its Green Drop score for the Kirkwood WWTW. However, the municipality showed no implementation of necessary programmes. Implementation of these programmes would help the SRVM meet the General Standard licence conditions (part of SDC) which would help the Uie River meet the RDM goals set for it.

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Lacher, Laurel Jane 1964. « Recharge characteristics of an effluent dominated stream near Tucson, Arizona ». Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/191199.

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Almost 90% of the treated sewage effluent processed by the two treatment plants serving the greater Tucson area is available for passive recharge through the Santa Cruz River streambed north of Tucson. In the absence of any major disturbance of the effluent channel, the recharge capacity of the streambed materials decreases over time as microbial activity, and possibly suspended sediments settling out of solution, act to clog the surficial sediments under the effluent stream. Effluent stream transmission-loss measurements made over the period from November 1994 to August 1995 provided data used to determine the average vertical hydraulic conductivity of the low-flow channel in the study reach through simulations using the computer model known as KINEROS2. Saturated hydraulic conductivity (KSAT) served as the calibration parameter in the model. The appropriate KSAT value was chosen for each set of field data by matching the observed and simulated downstream hydrographs for the study reach. KSAT values were corrected for viscosity changes resulting from changing average daily surface water temperatures over the study period. Saturated hydraulic conductivity values for the effluent stream channel ranged from a maximum of 37 mm/hr in January, 1995, following several major winter storms, to a minimum of 11 mm/hr in August, 1995, after a nearly six-month interstorm period. The saturated hydraulic conductivity values decay exponentially with time after the last major winter storm. The mathematical model describing this decay may be used to estimate effluent recharge rates under similar future meteorological and climatological conditions.

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Santos, Bruna Souza dos. « Sistema de tratamento híbrido utilizado na remoção do corante reativo 5g de um efluente têxtil sintético ». Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1274.

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CNPQ; Fundação Araucária; FPTI
Nos últimos anos observou-se um crescimento das atividades industriais que provocou impactos significativos aos recursos naturais, e as preocupações com o ambiente em geral adquirem especial importância. Neste contexto, a indústria têxtil considerada uma importante atividade responsável por parte desse desenvolvimento, se caracteriza como geradora de efluente líquido amplamente poluidor devido ao grande volume de água necessária nesse processo produtivo. Levando em consideração os métodos convencionais e também as dificuldades no tratamento dos efluentes têxteis, o processo eletrolítico conhecido como eletrofloculação se constitui em uma possibilidade importante. Este processo envolve a desestabilização de poluentes emulsificados, ou em suspensão, em meio aquoso. Desta forma o objetivo deste trabalho foi implantar um sistema de tratamento híbrido utilizado na remoção do corante reativo azul 5G de um efluente têxtil sintético, através da eletrofloculação associada a adição de coagulante natural a base de Moringa oleífera Lam, a fim de potencializar o nível de tratamento que seria alcançado com as técnicas utilizadas isoladamente Inicialmente trabalhou-se exclusivamente com a eletrofloculação para a remoção do corante. As variáveis analisadas foram: ddp (diferença de potencial aplicado), tempo e pH. Considerando o intervalo de confiança de 95% somente o termo quadrático da ddp e o termo linear do pH se mostraram significativos. Os valores de remoção da cor para os ensaios variaram de 64,38 a 90,87% e para a validação uma remoção média de 89,01%, valores muito próximos do predito pelo modelo. Na sequência foi realizada a otimização das condições para obtenção do extrato aquoso de Moringa oleífera. Avaliou-se as seguintes condições: salinidade e tempo de extração. A concentração do coagulante obtido, em água turva sintética também foi um dos fatores estudados. As melhores condições para o extrato aquoso de Moringa oleífera foram: 20 segundos de agitação em ultrassom, e solução de 20% em cloreto de sódio. Para potencializar o nível de tratamento as duas técnicas (eletrofloculação e coagulante natural a base de Moringa oleífera), foram testadas inicialmente em batelada e na sequência em fluxo contínuo. Os ensaios em batelada foram divididos em duas partes, o primeiro DCCR avaliou a intensidade de corrente elétrica (I), o tempo da eletrofloculação e a concentração do coagulante (MO), o qual obteve uma remoção de cor de 77,27% a 91,33%. Porém, nenhum termo foi significativo, mas o tempo apresentou menor efeito. Sendo assim, um novo planejamento foi realizado, o segundo DCCR, fixando o tempo na condição mínima, além das faixas de I e MO que também foram reduzidas. Obteve-se então uma remoção da cor para os ensaios de 13,45 a 80,8%, e para a validação uma remoção média de 86,56%. Para o módulo contínuo, as variáveis estudadas foram a intensidade de corrente elétrica (I), concentração do coagulante (MO) e tempo de retenção hidráulica (TRH). Dentre elas somente o TRH não se mostrou significativo. A remoção da cor variou de 8,46% a 90,25%. Nestes ensaios também foram realizados as análises das concentrações de Ferro Residual, e os valores obtidos variaram de 3,70 mg.L-1 a 9,03 mg.L-1, ficaram abaixo do valor máximo permissível pela Legislação (15 mg.L-1). Para maximizar a remoção da cor e minimizar a concentração de ferro residual, a função desejabilidade do software STATISTICA™ foi utilizada e nessas condições somente a I e a MO foram significativas. A partir da validação foi possível observar a tendência de remoção prevista pelo modelo. Obteve-se uma remoção da cor para a validação de 71,38% e uma concentração média de ferro residual de 5,2237 mg. L-1, porém, com um erro distante do esperado (32,85%).
In recent years there has been a growth of industrial activities that caused significant impacts to natural resources, and concerns about the environment in general are of particular importance. In this context, the textile industry considered an important activity responsible for part of that development is characterized as liquid effluent generating widely polluter due to the large volume of water needed in this production process. Taking into account the conventional methods and also the difficulties in treating textile effluents, the electrolytic process known as eletrofloculation constitutes an important possibility. This process involves the destabilization of the emulsified pollutants, or suspension in aqueous medium. Thus the aim of this study was to implement a hybrid treatment system used in removing the blue reactive dye 5G of a synthetic textile effluent by eletrofloculation associated with adding natural coagulant the basis of Moringa Oleifera Lam, in order to enhance the level treatment would be achieved with the techniques used alone initially worked up exclusively with eletrofloculation to remove the dye. The variables analyzed were: ddp (potential difference applied), time and pH. Whereas the 95% confidence interval only the quadratic term of the linear term DDP and pH were significant. The removal of color values for the tests ranged from 64.38 to 90.87% and validating an average removal of 89.01%, very close values predicted by the model. Following was carried out to optimize the conditions for obtaining the aqueous extract of Moringa oleifera. Salinity and extraction time: The following conditions were evaluated. The concentration of the coagulant obtained in synthetic turbid water was also one of the factors studied. The best conditions for the aqueous extract of Moringa oleifera were 20 seconds of ultrasound in agitation, and solution of 20% sodium chloride. To enhance the level of treatment the two techniques (eletrofloculation and natural coagulant Moringa oleifera the base), were initially tested in batch and following streaming. The batch tests were divided into two parts, the first CCRD evaluated the intensity of electric current (I), the time eletrofloculation and concentration of the coagulant (MO), which obtained a color removal of 91 to 77.27% 33%. But no term was significant, but time showed less effect. Thus, a new planning was done, the second CCRD, setting the time at a minimum, in addition to the R and MO tracks that were also reduced. There was thus obtained a removal color for testing 13.45 to 80.8%, and validating an average removal of 86.56%. For the continuous form, the variables studied were the intensity of electric current (I), the coagulant concentration (MO) and hydraulic retention time (HRT). Among them only HRT was not significant. The color removal ranged from 8.46 % to 90.25%. In these assays were also performed the analysis of the residual iron concentrations, and the values obtained ranged from 3.70 mg L- 1 to 9.03 mg.L-1, were below the maximum value allowable by law (15 mg.L-1). To maximize the removal of color and minimize the residual concentration of iron, the desirability function STATISTICA ™ software was used and under these conditions only I and MO were significant. From the validation was observed removing trend predicted by the model. Obtained was a color removal for the validation of 71.38 % and an average concentration of 5.2237 mg.L-1 of residual iron, but with a far from the expected error (32.85%).

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Lopes, Thiara Reis. « Caracterização do esgoto sanitário e lodo proveniente de reator anaeróbio e de lagoas de estabilização para avaliação da eficiência na remoção de contaminantes ». Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1285.

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CAPES
As Estações de Tratamento de Esgoto (ETEs), são utilizadas com o objetivo de simular os fenômenos naturais de degradação em condições controladas para promover o tratamento dos esgotos, durante este processo, ocorre à produção de um subproduto denominado lodo de esgoto, constituído basicamente por uma mistura de matéria orgânica e inorgânica, que durante o processo de tratamento do esgoto permanece acumulada no sistema. As características do esgoto e do lodo estão relacionadas com as atividades antrópicas, condições climáticas, avanços tecnológicos que também contribuem com a inserção de compostos de difícil degradação, raramente tratados e removidos por processos convencionais. O objetivo desta pesquisa foi avaliar as características do esgoto e do lodo gerado em dois sistemas convencionais aplicados no tratamento do esgoto, estimar a eficiência dos sistemas e indicar o melhor potencial uso agrícola do lodo produzido. Para isso, foram determinados no afluente e efluente dos sistemas de tratamento biológico os parâmetros físico-químicos (pH, temperatura, oxigênio dissolvido, sólidos totais, sólidos totais fixos, sólidos totais voláteis, sólidos sedimentáveis, Demanda Química de Oxigênio (DQO), nitrogênio amoniacal). No lodo foram determinados parâmetros físico-químicos (pH, fósforo, potássio, íons metálicos, sólidos totais, sólidos totais fixos, sólidos totais voláteis, umidade, matéria orgânica e carbono orgânico total) e biológicos (coliformes termotolerantes, E. coli, Salmonella sp.). Os isolados de E. coli e Salmonella sp. foram submetidos a testes de susceptibilidade a agentes antimicrobianos. Os resultados indicaram que os esgotos avaliados apresentaram pH próximos à neutralidade e temperaturas ótimas para as atividades bacterianas. Ao comparar os sistemas de tratamento, a ETE operada com lagoas foi mais eficiente na conversão de nitrogênio amoniacal, sólidos e menor eficiência na redução da DQO. Todos os parâmetros avaliados no esgoto, apresentaram concentrações inferiores aos limites estabelecidos na legislação, exceto o nitrogênio amoniacal, e em determinadas amostragens a DQO e o OD. Em relação ao lodo, este apresentou pH próximos à neutralidade, a concentração de fósforo, potássio e matéria orgânica no lodo do sistema operado com RALF foi superior a do sistema operado com lagoas. Às concentrações dos íons metálicos no lodo do RALF foram superiores às do lodo do leito de secagem, nas lagoas essas concentrações reduziram durante o processo de tratamento. Ao comparar as ETEs, às concentrações dos íons metálicos foram maiores no lodo do RALF, exceto Mn e Ni, e a concentração de Fe foi semelhante entre os sistemas. No lodo do RALF, do leito de secagem e das lagoas foram detectadas colônias de Salmonella sp. resistentes à amoxicilina (10µg), tetraciclina (30µg) e cefalotina (30µg). As colônias de E. coli, foram sensíveis apenas à gentamicina. Este estudo possibilitou avaliar a eficiência destes sistemas convencionais de tratamento de esgotos, os resultados evidenciam a necessidade de utilizar métodos adequados de tratamento que possibilitem a remoção desses antibióticos e inativação dos microrganismos patogênicos, pois indicam um potencial risco das ETEs na dispersão desses no ambiente.
The Wastewater Treatment Plants (WWTPs) are used in order to simulate the natural degradation phenomena using controlled conditions to promote sewage treatment, a byproduct called sewage sludge is produced during this process, this is one blend of organic and inorganic material, it was accumulated in the system during the sewage treatment process. The sewage and sludge characteristics are related to human activities, weather conditions. Technological advances can contribute to the insertion of some compounds that are difficult to degrade, rarely treated and removed by conventional methods. This research aims to evaluate the sewage and sludge characteristics, estimating the efficiency of two conventional treatment systems and verify the agricultural potential use of sludge produced. For this, were determined in the influent and effluent of the biological systems of wastewater treatment some physico-chemical parameters (pH, temperature, Dissolved Oxygen (DO), total solids, total fixed solids, total volatile solids, settleable solids, chemistry oxygen demand (COD), ammonia nitrogen). In the sludge were determined physico-chemical parameters (pH, total solids, total fixed solids, total volatile solids, total phosphorus, total K, metals, humidity, organic matter and total organic carbon) and biological (CTT, E. coli, Salmonella sp.). The isolates of E. coli and Salmonella sp. were tested to antimicrobial agents. The results indicated the pH in sewage was near to neutrality and optimum temperatures for bacterial activities. By comparing the treatment systems, the WWTP operated with ponds was more efficient in ammonia nitrogen conversion, removing solids and less efficient in reducing COD. All results were below the limits established by law, except ammonia nitrogen and in some samples the DO and COD. The pH in sludge was slightly acid and near neutrality. The concentration of phosphorus, potassium and organic material in the sludge collected in the system operated with RALF exceeded the system operated with ponds. The concentrations of metal ions in sludge of RALF were higher than those of the sludge drying bed, in ponds the concentrations decreased during the treatment process, to compare the WWTPs, the concentrations of metal ions were higher in RALF sludge, except Mn and Ni, and the Fe concentration was similar. In the sludge of RALF, in the drying bed and ponds were detected Salmonella sp. resistant to amoxicillin (10µg), tetracycline (30µg) and cephalothin (30µg). The E. coli were susceptible only to gentamicin. This study evaluated the efficiency of these conventional systems applied in sewage treatment, the results suggest the need to use appropriate methods of treatment to removal of these antibiotics and inactivation the pathogenic microorganisms, this indicate a potential hazard of these WWTPs in the dispersion of the environment.

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Coogan, Melinda Ann. « Bioaccumulation of Triclocarban, Triclosan, and Methyl-triclosan in a North Texas Wastewater Treatment Plant Receiving Stream and Effects of Triclosan on Algal Lipid Synthesis ». Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc3986/.

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Triclosan (TCS) and triclocarban (TCC), widely used antimicrobial agents found in numerous consumer products, are incompletely removed by wastewater treatment plant (WWTP) processing. Methyl-triclosan (M-TCS) is a more lipophilic metabolite of its parent compound, TCS. The focus of this study was to quantify bioaccumulation factors (BAFs) for TCS, M-TCS, and TCC in Pecan creek, the receiving stream for the City of Denton, Texas WWTP by using field samples mostly composed of the alga Cladophora sp. and the caged snail Helisoma trivolvis as test species. Additionally, TCS effects on E. coli and Arabidopsis have been shown to reduce fatty acid biosynthesis and total lipid content by inhibiting the trans-2 enoyl- ACP reductase. The lipid synthesis pathway effects of TCS on field samples of Cladophora spp. were also investigated in this study by using [2-14C]acetate radiolabeling procedures. Preliminary results indicate high TCS concentrations are toxic to lipid biosynthesis and reduce [2-14C]acetate incorporation into total lipids. These results have led to the concern that chronic exposure of algae in receiving streams to environmentally relevant TCS concentrations might affect their nutrient value. If consumer growth is limited, trophic cascade strength may be affected and serve to limit population growth and reproduction of herbivores in these riparian systems.

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Mtimkulu, Yandiswa. « Monitoring extracellular enzyme activities and microbial population numbers during composting of winery solid waste ». Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2344.

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Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2016.
Waste management in winery and distillery industries faces numerous disposal challenges as large volumes of both liquid and solid waste by-products are generated yearly during cellar practices. Composting has been suggested a feasible option to beneficiate solid organic waste. This incentivized the quest for efficient composting protocols to be put in place. The objective of this study was to experiment with different composting strategies for spent winery solid waste. Compost materials consisting of chopped pruning grape stalks, skins, seed and spent wine filter material consisting of a mixture of organic and inorganic expend ingredients were mixed in compost heaps. The filter material component varied (in percentage) among five treatments: T1 (40%) lined, T2 (20%) lined, T3 (0%) lined, T4 (40%) grinded material, lined and T5 (40%) unlined. Composting was allowed to proceed in open air over 12 months, from autumn to summer. Indicators such as temperature, moisture, enzyme activities, microbial counts, pH, and C/N ratio, were recorded. Generally, season (df =3, 16, P < 0.05) had significant effects (df =1, 3, P < 0.05) on heap temperature and moisture in all treatments. Similarly, microorganisms (actinobacteria and heterotrophs) varied significantly in all treatments in response to seasonal change (df = 3, 16; P < 0.05). Enzyme activities fluctuated in accordance with seasonal factors and compost maturity stages, with phosphatases, esterases, amino-peptidases, proteases and glycosyl-hydrolases being most prominent. Compared to treatments T2 and T3, compost treatments with higher percentage waste filter materials (T1, T4 and T5) had higher N (16100-21300 mg/kg), P (1500-2300 mg/kg), K (19800-28200 mg/kg), neutral pH, and lower C/N ratios (13:1-10:1), which were also comparable with commercially produced composts. Filter materials therefore, appears to be a vital ingredient for composting of winery solid waste.

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Rinquest, Zainab. « Poultry slaughterhouse wastewater treatment using a static granular bed reactor (Sgbr) coupled with a hybrid sidestream membrane bioreactor ». Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2638.

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Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2017.
An increase in the demand for poultry products coupled with the potable water shortages currently experienced in South Africa (SA), attributed to climate change among other factors, makes it crucial for SA to develop water conservation strategies to minimize potable water consumption by water-intensive industries, such as the poultry industry. The development of innovative wastewater treatment processes is therefore paramount in attempting to counteract the large quantity of wastewater generated as well as to manage the environmental health concerns arising from poultry slaughterhouse wastewater (PSW) discharge into the environment. Moreover, increasing wastewater treatment costs and the implementation of increasingly stringent government legislation to mitigate environmental pollution whilst minimizing fresh water source contamination, requires that wastewater such as PSW, be adequately treated prior to discharge. This study, investigated the feasibility of treating PSW from a poultry slaughterhouse to: 1) a water quality standard compliant with industrial wastewater discharge standards and 2) for possible re-use purposes. The performance of a lab-scale PSW treatment system consisting of an anaerobic static granular bed reactor (SGBR) followed by single stage nitrificationdenitrification (SSND) bioreactor and sidestream ultrafiltration membrane module (ufMM) post-treatment systems, were evaluated, with the objective being to: assess the treatment efficiency of the individual treatment systems namely; the SGBR, SSND bioreactor, and ufMM, under varying operational conditions, as well as to determine the performance of the overall designed PSW treatment system. The down-flow SGBR (2 L) was used to reduce the organic matter (COD, BOD5, and FOG) and total suspended solids (TSS) in the PSW. Anaerobic granules from a full-scale mesophilic anaerobic reactor treating brewery wastewater were used to inoculate the SGBR, and the PSW used as feed was obtained from a local poultry slaughterhouse (Western Cape, South Africa). The SGBR was operated continuously at mesophilic temperature (35-37 °C) without pH modification and under varying HRTs (24, 36, 48, 55, and 96 h) and OLRs (0.73 to 12.49 g COD/Lday), for a period of 138 days. The optimization of the SGBR, with regard to a suitable HRT and OLR, was determined using response surface methodology (RSM) and Design Expert® 10.0.3 statistical software. Periodic backwashing of the SGBR system was performed using stored effluent, i.e. treated PSW.

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Belini, Aldria Diana. « Otimização da remoção da matéria carbonácea e nitrogenada do esgoto sanitário por reator anaeróbio e aeróbio de leito fixo ». Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/1937.

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CAPES; CNPq; Sanepar; Fundação Araucária
O aumento da população agrava a qualidade dos corpos receptores existentes, devido a concentração dos despejos de esgotos sanitários com elevadas cargas carbonáceas e nitrogenadas. Existem inúmeras operações de tratamento, porém, a aplicação dos processos biológicos, na maioria dos casos é a alternativa mais econômica. Logo, este trabalho tem por objetivo, otimizar a remoção da matéria carbonácea e nitrogenada de esgotos sanitário por sistema combinado composto de reator anaeróbio e aeróbio de leito fixo. O sistema foi composto de reatores anaeróbio e aeróbio de leito fixo, com escoamento ascendente e fluxo continuo, base retangular e volume útil de 19,8 L e 19,3 L respectivamente, mais um dispositivo de separação de sólidos líquidos com volume útil de 7,3 L (TDH de 8h em cada reator) e 9,8 L (TDH de 6h em cada reator). O meio suporte para imobilização da biomassa era constituído de anéis corrugados de Policloreto de Polivinila (PVC). O Sistema foi operado em 6 etapas distintas em que foi variado a taxa de recirculação (etapa 1 50%, etapa 2 100% e etapa 3 150%) e vazão de aeração (etapa 4 10 L.min-1, etapa 5 5 L.min-1 e etapa 6 2,5 L.min-1). Para a avaliação do sistema, determinou-se os seguintes parâmetros físico-químicos: temperatura do líquido (TL), pH, alcalinidade total (AT), alcalinidade a bicarbonato (AB), ácidos voláteis (AV), oxigênio dissolvido (OD), demanda química de oxigênio (DQO) nitrogênio total kjeldahl (N-NTK), nitrogênio amoniacal (N-amoniacal), nitrito (N-NO2-), nitrato (N-NO3-) e fósforo total (P). A avaliação do comportamento hidrodinâmico foi realizada pela técnica de estímulo-resposta tipo pulso com injeção do corante Eosina Y. Os resultados obtidos nas três primeiras etapas com influência da variação da taxa de recirculação (50%, 100 % e 150 %), apresentaram remoções da concentração de matéria orgânica em termos de DQO(amostras brutas) superiores a 97 %, em relação a concentração de nitrogênio, a remoção de N-NTK ficou superior a 95 %; foi possível concluir que quanto maior a taxa de recirculação maior é a eficiência de remoção de nitrogênio e menores são os valores de nitrito e nitrato, entretanto cabe ressaltar que o aumento da taxa de recirculação provoca o aumento da concentração de OD no reator anaeróbio o que pode provocar o desequilíbrio do processo. Ao observar a influência da variação da vazão de aeração com taxa de recirculação constante de 100 %, as remoções de matéria orgânica apresentaram remoção de DQO (amostras brutas) superiores 98 a % enquanto a remoção de nitrogênio caiu conforme a diminuição da vazão de aeração (Qa) com eficiências de remoção de N-NTK superiores a 96% (Qa = 10 L.min-1), 90 % (Qa = 5 L.min-1) e 45 % (Qa = 2,5 L.min-1). E em relação a variação do TDH, na remoção de matéria orgânica, obteve valores de remoção superiores de DQOamostras brutas a 98 % (TDH de 8h em cada reator) e 99 % (TDH de 6h em cada reator) enquanto que para remoção de nitrogênio as eficiências foram superiores a 96% para ambos os TDH testados o que evidência que o sistema combinado apresentou boa capacidade de amortecer a variação de cargas hidráulicas como orgânicas.
The increase in population worsens the quality of existing receiving bodies, because the concentration of sewage dumps with high organic and nitrogen loads. There are numerous processing operations, however, the application of biological processes, in most cases is the most economical alternative. Thus, this study aims to optimize the removal of carbonaceous and nitrogenous matter sanitary sewer system consists of a combined anaerobic and aerobic fixed bed reactor. The system was composed of anaerobic and aerobic fixed-bed reactors, with upward flow and continuous flow, rectangular base and useful volume of 19.8 L and 19.3 L, respectively, plus a solid liquid separation device with a volume of 7 3 L (HDT 8 h in each reactor) and 9.8 L (HDT 6 h in each reactor). The medium support for biomass immobilization consisted of corrugated rings Polyvinyl Polyvinyl (PVC). The system was operated in six different stages in which was varied the recirculation rate (50% step 1, 100% step 2 and step 3 150%) and flow aeration (step 4 10 L.min-1, Step 5 5 L .min-1 and step 6 2.5 L.min-1). For the evaluation system, it was determined the following physicochemical parameters: liquid temperature (TL), pH, total alkalinity (AT), bicarbonate alkalinity (AB), volatile acids (AV), dissolved oxygen (DO), chemical oxygen demand (COD) Total kjeldahl nitrogen (N-TKN), ammonia (N-ammonia), nitrite (N-NO2-), nitrate (N-NO3-) and phosphorus (P). The hydrodynamic behavior evaluation was performed by pulse type stimulus-response technique of injection of the dye Eosin Y. The results obtained in the first three steps with recirculation rate influence of variation (50%, 100% and 150%) showed removal concentration of organic matter in terms of COD (raw samples) greater than 97%, for nitrogen concentrations, the removal of N-TKN was greater than 95%; it was concluded that the higher the recirculation rate is nitrogen removal efficiency and lower the nitrite values and nitrate, however it is worth noting that increasing the recirculation rate causes an increase of OD concentration in the anaerobic reactor which may cause the imbalance of the process. To observe the influence of variation in the flow aeration with constant recirculation rate of 100%, the removal of organic matter showed a COD(raw samples) removal higher than 98% while the nitrogen removal fell as the reduction of aeration flow ( Qa) with N-TKN removal efficiencies exceeding 96% (Qa = 10 L.min-1), 90% (Qa = 5 L.min-1) and 45% (Qa = 2.5 L.min-1). And regarding the variation of TDH, in the removal of organic matter, obtained higher removal values DQO(raw samples) 98% (HDT of 8 hours in each reactor) and 99% (HDT of 6 hours in each reactor) while for nitrogen removal efficiencies were higher than 96% for both tested HDT which shows that the combined system showed a good ability to cushion the variation of hydraulic and organic fillers.

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Holtman, Gareth Alistair. « Design, installation, and assessment of a biological winery wastewater treatment system ». Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2573.

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Thesis (MTech (Civil Engineering))--Cape Peninsula University of Technology, 2017.
Currently in South Africa, most wastewater from small cellars is pH-adjusted and disposed of via land irrigation. This practice can lead to environmental degradation. There is a need for low cost, low maintenance solutions for the treatment of cellar effluent. Constructed wetlands provide such an option. However, the use of plants is problematic because winery effluent can be phytotoxic. After successful initial laboratory-scale experiments, an in-situ pilot scale biological sand filter (unplanted constructed wetland) system was designed, installed, and used to treat effluent from a small winery in the Western Cape, South Africa. The system is off-grid, totally self-regulating, and uses a modular approach which allows for the addition and subtraction of filter modules within the system to alter treatment capacity, retention time and/or rest filter modules. The system can be easily integrated into existing settling basins and/or retention ponds at small wineries. The biological sand filter was operational for 610 days, and showed promising results. The average chemical oxygen demand removal efficiency was 81% (range: 44-98%) with an average effluent of 324 mg/L, and an average flow rate of 413 L/day after the acclimation (start-up) period. The average hydraulic loading rate after the initial start-up period was 143 L/m3 sand day-1 (range: 67-222/m3 sand day-1), with an organic loading rate of 205 gCOD/m3 of sand day-1 (range: 83-338 gCOD/m3 sand day-1) which resulted in an organic removal rate of 164 gCOD/m3 of sand day-1. There was an average of 67% removal of total phenolics, thereby reducing the potential phytotoxicity of the effluent. In addition, there was a 1.6 times increase in calcium concentration, a 29% decrease in the average sodium adsorption ratio, and complete passive neutralisation of the acidic winery wastewater (final effluent pH range: 6.63 – 8.14. The findings of this study compare well with previous laboratory studies conducted with synthetic and authentic winery effluent. The system can potentially provide a low cost, energy efficient, low maintenance, sustainable means of treating cellar effluent at small wineries. Uptake of this technology may alleviate environmental degradation caused by irrigating land with inadequately treated effluent.

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Baerenklau, Amy L. (Amy Lyn). « Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX ». Thesis, University of North Texas, 1996. https://digital.library.unt.edu/ark:/67531/metadc279107/.

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The City of Denton Pecan Creek Wastewater Treatment Facility has periodically failed effluent toxicity testing. A Toxicity Identification Evaluation has determined that Diazinon in the effluent is contributing to the observed toxicity. Chlorpyrifos is also implicated as a factor. The City of Denton constructed a half acre experimental wetland to remove Diazinon related toxicity. Results from spiking and microcosm experiments indicate that the wetland can reduce the Diazinon.

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Xiong, Xianzhe, et mikewood@deakin edu au. « Heavy metal accumulation in soils at three field sites subject to effluent irrigation ». Deakin University. School of Ecology and Environment, 2003. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20050902.110403.

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Three field sites were chosen to study the environmental assimilative capacity of heavy metals in soil. These sites were the Werribee Farm and the Myome Farm in Australia and Shenyang Zhangshi Irrigation Area in China. The Werribee Farm and the Shenyang Zhangshi Irrigation Area received sewage treatment and application on land for a long time. The Myome farm is an experimental site in which investigations on land application of municipal wastewater on water repellent soils is currently being trailed. Heavy metal contamination, in particular Cr, Cu and Zn, in the Land Filtration soil of Werribee Farm was widespread. More than a century of sewage irrigation has occurred in the Werribee Farm. The temporal distribution pattern of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in the soil at this site follow an exponential trend with time and the spatial distribution pattern of accumulation of heavy metals in different paddocks correlates with the number of years of sewage irrigation at that site in the Farm. Extensive sewage irrigation at Shenyang Zhangshi Irrigation Area resulted in significant Cd pollution in soil-plant (rice) system and poses a significant threat to the health of local people. Even after eight years since cessation of sewage irrigation, the bioavailable fractions of Cd in the soil as analyzed by sequential extraction techniques were very high thus illustrating long-term persistence. The simultaneous competitive adsorption of metals in water repellent soils (at Myome Farm in South Australia) was studied. In the competitive situation, Cr, Pb and Cu are the heavy metal cations more strongly adsorbed by the soil, whereas Cd, Ni and Zn are the least adsorbed. The increase in Freundlich adsorption capacity by clay amendment suggested that clayed soils are capable sorption of higher heavy metal loadings compared to the non-clayed water repellent soil, which is more vulnerable to heavy metal inputs. A simple model of environmental assimilative capacity is proposed. The results of comparison of the three field sites shows that the Werribee Farm has a higher environmental assimilative capacity of heavy metals in soil than the soils at Shenyang Zhangshi Irrigation Area and Myome Farm, however heavy metal contamination at Werribee Farm is still a concern. The model of environmental assimilative capacity of heavy metals in soil is an effective tool to assist management of effluent applied land irrigation systems and can be used to better design environmental engineering systems.

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Maschmann, Gerald F. « Recovery of the Fish Population of a Municipal Wastewater Dominated, North Texas Creek After a Major Chlorine Disturbance ». Thesis, University of North Texas, 2002. https://digital.library.unt.edu/ark:/67531/metadc3230/.

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This study evaluated the effects of a major chlorine disturbance on fish communities in Pecan creek by the City of Denton's Pecan Creek Water Reclamation Plant. Fish communities in Pecan Creek were sampled using a depletion methodology during February, April, July, and November, 1999. February and April sampling events showed that the fish communities were severely impacted by the chlorine. Sampling during July and November showed fish communities recovered in Pecan Creek. The first-twenty minutes of shocking and seining data were analyzed to mirror an equal effort methodology. This methodology was compared to the depletion methodology to see if the equal effort methodology could adequately monitor the recovery of Pecan Creek after the chlorine disturbance. It was determined that the equal effort methodology was capable of monitoring the recovery of Pecan Creek, but could not accurately represent the fisheries community as well as the depletion method. These data using the twenty-minute study were compared to a previous study. Results of this study were similar to those found in a previous study, although fish communities were more severely impacted and took longer to recover.

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Hendricks, Nicolette Rebecca. « The application of high capacity ion exchange absorbent material, synthesized from fly ash and acid mine drainage, for the removal of heavy and trace metals from secondary co-disposed process waters ». Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&amp.

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The objective of this study was to investigate the feasibility of the application of low cost high capacity inorganic ion exchange material, synthesized form collected fly ash and acid mine drainage solid residues, for the decontamination of secondary co-disposal process waters, with emphasis on investigating the processes governing the solid/solution interface.

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