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Assessment of the prevalence of faecal coliforms and Escherichia coli o157:h7 in the final effluents of two wastewater treatment plants in Amahlathi Local Municipality of Eastern Cape Province, South AfricaAjibade, Adefisoye Martins January 2014 (has links)
The production of final effluents that meet discharged requirements and guidelines remain a major challenge particularly in the developing world with the resultant problem of surface water pollution. This study assessed the physicochemical and microbiological qualities of two wastewater treatment works in the Eastern Cape Province of South Africa in terms of the prevalence of faecal coliforms and Escherichia coli O157:H7 over a five month period. All physicochemical and microbiological analyses were carried out using standard methods. Data were collected in triplicates and analysed statistically using IBM SPSS version 20.0. The ranges of some of the physicochemical parameters that complied with set guidelines include pH (6.7 – 7.6), TDS (107 – 171 mg/L), EC (168 – 266 μS/cm), Temperature (15 – 24oC), NO3- (0 – 8.2 mg/L), NO2- (0.14 – 0.71 mg/L) and PO4 (1.05 – 4.50 mg/L). Others including Turbidity (2.64 – 58.00 NTU), Free Cl (0.13 – 0.65 mg/L), DO (2.20 – 8.48 mg/L), BOD (0.13 – 6.85 mg/L) and COD (40 – 482 mg/L) did not comply with set guidelines. The microbiological parameters ranged 0 – 2.7 × 104 CFU/100 ml for FC and 0 – 9.3 × 103 for EHEC CFU/100 ml, an indication of non-compliance with set guidelines. Preliminary identification of 40 randomly selected presumptive enterohemorrhagic E. coli isolates by Gram’s staining and oxidase test shows 100% (all 40 selected isolates) to be Gram positive while 90% (36 randomly selected isolates) were oxidase negative. Statistical correlation between the physicochemical and the microbiological parameters were generally weak except in the case of free chlorine and DO where they showed inverse correlation with the microbiological parameters. The recovery of EHEC showed the inefficiency of the treatment processes to effectively inactivate the bacteria, and possibly other pathogenic bacteria that may be present in the treated wastewater. The assessment suggested the need for proper monitoring and a review of the treatment procedures used at these treatment works.
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Assessment of the prevalence of virulent Eschericia coli strains in the final effluents of wastewater treatment plants in the Eastern Cape Province of South AfricaOsode, Augustina Nwabuje January 2010 (has links)
Escherichia coli (E. coli) is a common inhabitant of surface waters in the developed and developing worlds. The majority of E. coli cells present in water are not particularly pathogenic to humans; however, there are some present in small proportion that possess virulence genes that allow them to colonize the digestive tract. Pathogenic E. coli causes acute and chronic diarrheal diseases, especially among children in developing countries and in travelers in these locales. The present study, conducted between August 2007 and July 2008, investigated the prevalence and distribution of virulent E. coli strains as either free or attached cells in the final effluents of three wastewater treatment plants located in the Eastern Cape Province of South Africa and its impact on the physico-chemical quality of the receiving water body. The wastewater treatment plants are located in urban (East Bank Reclamation Works, East London), peri-urban (Dimbaza Sewage Treatment Works) and in rural area (Alice Sewage Treatment Works). The effluent quality of the treatment plants were acceptable with respect to pH (6.9-7.8), temperature (13.8-22.0 °C), dissolved oxygen (DO) (4.9-7.8 mg/L), salinity (0.12-0.17 psu), total dissolved solids (TDS) (119-162 mg/ L) and nitrite concentration (0.1-0.4 mg/l). The other xii physicochemical parameters that did not comply with regulated standards include the following: phosphate (0.1-4.0 mg/L); chemical oxygen demand (COD) (5-211 mg/L); electrical conductivity (EC) (237-325 μS/cm) and Turbidity (7.7-62.7 NTU). Results suggest that eutrophication is intensified in the vicinity of the effluent discharge points, where phosphate and nitrate were found in high concentrations. Presumptive E. coli was isolated from the effluent samples by culture-based methods and confirmed using Polymerase Chain Reaction (PCR) techniques. Antibiogram assay was also carried out using standard in vitro methods on Mueller Hinton agar. The viable counts of presumptive E. coli for the effluent samples associated with 180 μm plankton size ranged between 0 – 4.30 × 101 cfu/ml in Dimbaza, 0 – 3.88 × 101 cfu/ml in Alice and 0 – 8.00 × 101 cfu/ml in East London. In the 60 μm plankton size category E. coli densities ranged between 0 and 4.2 × 101 cfu/ml in Dimbaza, 0 and 2.13 × 101 cfu/ml in Alice and 0 and 8.75 × 101 cfu/ml in East London. Whereas in the 20 μm plankton size category presumptive E. coli density varied from 0 to 5.0 × 101 cfu/ml in Dimbaza, 0 to 3.75 × 101 cfu/ml in Alice and 0 to 9.0 × 101 cfu/ml in East London. The free-living presumptive E. coli density ranged between 0 and 3.13 × 101 cfu/ml in Dimbaza, between 0 and 8.0 × 101 cfu/ml in Alice and between 0 and 9.5 × 101 cfu/ml in East London. Molecular analysis successfully amplified target genes (fliCH7, rfbEO157, ial and aap) which are characteristic of pathogenic E. coli strains. The PCR assays using uidA-specific primer confirmed that a genetic region homologous in size to the E. coli uidA structural gene, including the regulatory region, was present in 3 of the E. coli isolates from Alice, 10 from Dimbaza and 8 from East London. Of the 3 E. coli isolates from Alice, 1 (33.3%) was positive for the fliCH7 genes and 3 was positive for rfbEO157 genes. Out of the 10 isolates from Dimbaza, 4 were xiii positive for fliCH7 genes, 6 were positive for the rfbEO157 genes and 1 was positive for the aap genes; and of the 8 isolates from East London, 1 was positive for fliCH7 genes, 2 were for the rfbEO157 genes, 6 were positive for the ial genes. Antimicrobial susceptibility profile revealed that all of the E. coli strains isolated from the effluent water samples were resistant (R) to linezolid, polymyxin B, penicillin G and sulfamethoxazole. The E. coli isolates from Dimbaza (9/10) and East London (8/8) respectively were resistant to erythromycin. All the isolates were found to be susceptible (S) to amikacin, ceftazidime, ciprofloxacin, colistin sulphate, ceftriaxone, cefotaxime, cefuroxime, ertapenem, gatifloxacin, gentamycin, imidazole, kanamycin, meropenem, moxifloxacin, neomycin, netilmicin, norfloxacin and tobramycin. The findings of this study revealed that the Alice wastewater treatment plant was the most efficient as it produced the final effluent with the least pathogenic E. coli followed by the Dimbaza wastewater treatment plant. In addition, the findings showed that the wastewater treatment plant effluents are a veritable source of pathogenic E. coli in the Eastern Cape Province watershed. We suggest that to maximize public health protection, treated wastewater effluent quality should be diligently monitored pursuant to ensuring high quality of final effluents.
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Dealing with Wastewater and Water Purification from the Age of Early Modernity to the Present: An Inquiry Into the Management of the Ottawa RiverMurray, Matthew January 2012 (has links)
This thesis examines the impact of urban water infrastructure on the Ottawa River through an exploration of the City of Ottawa's historical development from the early modern period to the present. The primary aim is to explain how the Ottawa River came to be removed or ignored from the City of Ottawa's urban development strategy. The thesis focuses on the periods of 1910-1920 (early modernity) and 1999-2012 (present). The theories applied are risk, risk management, normal accident theory and the politics of infrastructure. The data and information for this thesis were primarily retrieved from the City of Ottawa website as well as from the archives of the City of Ottawa. The thesis identifies several factors explaining why the Ottawa River has been mistreated over time, as well as the challenges involved in reforming present-day practices and infrastructure. Several recommendations to fix the situation are advanced.
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Synthesis of a model for optimising a potable water treatment plant and water usage analysis in the Ugu DistrictMagombo, James January 2017 (has links)
Submitted in fulfillment of the requirements for the degree of Master of Engineering, Department of Industrial Engineering, Durban University of Technology, Durban, South Africa, 2017. / Access to clean and adequate water is a universal and basic human right that feeds into the 6th of the 17 Sustainable Development Goals (SDGs). This goal aims at ensuring availability and sustainable management of water and sanitation for all. Clean water is referred to as potable water, which is safe for human consumption and offer low risk of immediate or long term harm. Raw water undergoes rigorous processing which consists of coagulation, sedimentation, filtration, disinfection and storage, to produce potable water. Each module or stage consumes chemicals and energy resources and thus incurs costs.
To achieve the aim of the study, which was to synthesize an optimised potable water treatment network and a water usage analysis model, the Umzinto Water Treatment Plant (UWTP) and its distribution system was used as the study area. This treatment plant is located within Umdoni, a local municipality of the Ugu District Municipality in KwaZulu-Natal Province, South Africa.
This study’s objectives were fourfold and the first objective was to identify and quantify key raw water quality parameters affecting treatment at the UWTP. The second objective was to design a genetic algorithm for the potable water treatment process control. The third objective was to evaluate the Umzinto Water Distribution System’s Non-Revenue Water (NRW) while the fourth objective was to develop a model for water usage analysis.
For the first objective, data for water quality parameters for the water treatment from July 2006 to June 2013 were statistically analysed. This data were collected from the UWTP’s historical records. To improve the data’s integrity it was pre-processed using cubic hermite interpolation. After the pre-processing trend lines and box plots were used to determine the parameters’ significance compared to the standard values stipulated in the South African National Standard (SANS 241). The trend lines were used to analyse the frequency of observations that were higher than the standard values according to SANS 241. The box plots were used to determine the minimum, median, maximum and mean of the data sets. The mean values for each parameter were compared to the SANS 241 value to determine their significance. The raw water quality parameters were then correlated to the chemical dosages for lime, polymer, potassium permanganate and chlorine. The key parameters selected from the correlation analysis were algal count, manganese (Mn), iron (Fe), Escherichia coli, total coliforms, colour, odour, conductivity, turbidity, suspended solids (SS), pH, temperature, total organic carbon (TOC,) and Hardness.
A number of methods can be used to achieve such optimisation, including artificial neural networks, dynamic programming, linear and non-linear programming, and this study utilised a genetic algorithm as an optimisation tool to achieve the second objective of optimising water treatment at the UWTP. For the model development, data from the correlations obtained for objective 1 were used. The model was aimed at reducing the cost of chemical dosage and four chemical dosage prediction models were developed using genetic algorithms and these were then used to produce a combined chemical dosage cost prediction model. The programming interface utilised for these models was Matlab. In developing these models, the data were first pre-processed to remove outliers and fill in the blanks using a Microsoft Excel Add-in that was developed for this particular purpose. The next step involved a curve fitting exercise in Microsoft Excel 2013. Matlab was then used to code the genetic algorithm that combined and optimised the solutions obtained from the curve fittings. The results showed that genetic algorithms can be reliably used to predict the chemical dosages and hence reduce water treatment costs.
After treatment, water is pumped into the distribution system for consumption. It is therefore important to ensure that all the pumped out treated water reaches the consumer. The third objective therefore assessed the NRW for the Umzinto Water Distribution System for the period between July 2013 and June 2014. The data used for this objective was provided by the Ugu District Municipality. The method used combined the top-down approach and the component-based approach. This combined approach was modified to enable the calculation of all the components that are required in a standard South African Water Balance. The results showed that the distribution system had a high value of NRW, which was 27.9% of the System Input Volume. The major component of NRW was Real Losses, that is, losses that can be mitigated by improving maintenance.
The fourth objective was to develop a model for water usage analysis that would reduce the time taken to evaluate NRW and also improve the analysis of the NRW components using Microsoft Visual Basics 2012 and Microsoft SQL Server 2012 development interfaces. The Visual Basics enabled the development of a graphic user interface that was user-friendly and minimised the time taken to learn the software. The software platform developed was able to import the data required to construct a standard International Water Asssociation (IWA) Water Balance, calculate all the components of NRW, store historical data for the water distribution systems and report on a rolling year basis. A model for water usage analysis was developed and made available for usage by practitioners in Ugu District. The model was developed for the specific study area and further studies would be required in order to validate it in a different setting.
The results obtained for the first objective led to the conclusion that, there was very high pollution emanating from communities and activities close to the raw water sources, especially the EJ Smith Dam. The results from the first objective were also used to determine parameters for the models developed in the second objective. From objective two it was concluded that genetic algorithms can be reliably used to predict chemical dosages and hence reduce water treatment costs. The third objective’s results showed that 27.9% of treated water pumped into the distribution system is NRW. Which is a concern because 65% of this are real losses which have maintenance related problems. The fourth objective’s results showed the practicality of designing model that could be used determine all the important components of NRW that would take time to evaluate manually. It would also store historical data for the water distribution system and report on a rolling year basis. Implementation of this software would help minimise the errors associated with manual calculation of NRW and improve the availability of data for research and analysis.
From the research findings, it is recommended that the treatment plant should change the way it is dosing chemicals in the balancing tank. The method currently being used is prone to error. The analysis of NRW showed that Real Losses were a major challenge in the Umzinto Distribution System. There is need to develop a maintenance program to cater for leakage. Communities also need to be educated on the importance of reporting leakage in the network. / M
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Design and evaluation of a cost effective household drinking water treatment systemMahlangu, Themba Oranso 20 August 2012 (has links)
M.Sc. / The world is focusing on increasing the number of people who have access to safe drinking water due to the ascending numbers of drinking water related illnesses reported annually in rural areas where water is not treated before consumption. To meet this goal, household water treatment has to be introduced especially in places where homes are wide apart making centralised water treatment improbable. Most readily available household water treatment systems (HWTS) such as membrane filters may not be affordable in rural areas due to power requirements and degree of ability to use and maintain them. This study was therefore aimed at designing and constructing HWTS using readily available material such as sand, gravel, zeolites and clays. Five HWTS were designed, built, evaluated and compared based on their ability to remove chemical contaminants such as iron, arsenic and fluorides from drinking water. The types of filters that were used during this study are the biosand filter (BSF), a modified biosand filter with zeolites (BSFZ), a silver impregnated porous pot (SIPP) filter, a ceramic candle filter (CCF) and a bucket filter (BF). Effectiveness of the filters in reducing physical parameters such as turbidity and visual colour was also assessed. The water treatment devices had the following flow rates; 1.74 L/h – 19.20 L/h (BSFZ), 0.81 L/h – 6.84 L/h (BSF), 0.05 L/h – 2.49 L/h (SIPP) and 1.00 L/h – 4.00 L/h (CCF). The flow rates were high at the early stages of filter use and decreased with increase in the volume of water filtered through. The flow rates of the filters were affected by the turbidity of intake water which was between 1.74 NTU – 42.93 NTU and correlated to chlorophyll a concentrations. The household water treatment technologies reduced turbidity to levels less than 1 NTU (> 90% reduction) in the following order SIPP > BSFZ > BSF > CCF > BF. The filters achieved greater than 60% retention of calcium, magnesium, iron and arsenic. These contaminants with the exception of arsenic were reduced to acceptable levels of the South African National Standard of drinking water (SANS 241, 2004). Compared to the other filters, the BSFZ performed better in removing nitrates, phosphates and fluorides although the overall retention efficiency was low. Total organic carbon was removed greatly by the CCF (39%) and the least removal was by the BF. The overall performance of the filters in reducing contaminants from drinking water was in the order BSFZ > BSF > SIPP > CCF > BF. Filter washing vi resulted in an overall increase in the flow rates of the filters but negatively affected turbidity reduction. The filters still removed contaminants after total cumulative volumes of 1200 L (BSFZ, BSF, CCF and BF) and 300 L (SIPP) were filtered through the devices. The five evaluated filters have several advantages to the readily available technologies and the advantages include ease of construction, operation and maintenance. The filters are gravity driven and work independent of temperature. These HWTS incorporate safe storages fitted with spigots to eliminate recontamination of water when it is drawn for use. The filters can produce enough drinking and cooking water for a family of six members due to their high flow rates. The BSFZ, BSF, SIPP, CCF and BF may therefore be considered for treating contaminated water at household scale in places where water is taken directly from the source without treatment.
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Preparação e caracterização de membranas poliméricas de poli(fluoreto de vinilideno) para uso em nanofiltraçãoThürmer, Mônica Beatriz 05 August 2010 (has links)
A busca por tecnologias cada vez mais eficazes no tratamento de águas e efluentes fez com que o desenvolvimento de membranas desempenhasse um papel importante nos processos de separação. A nanofiltração apresenta-se como uma tecnologia promissora para remoção de sais multivalentes em soluções aquosas. O preparo de membranas poliméricas pela técnica de inversão de fases permite a obtenção de estruturas distintas. Neste estudo avaliou-se o uso de diferentes não-solventes no preparo de membranas de poli(fluoreto de vinilideno) pelo método de inversão de fases, quanto às características estruturais e propriedades funcionais. Foram utilizados como não-solventes: água destilada, solução de dodecil sulfato de sódio e etanol/água, resultando nas membranas denominadas MT1, MT2 e MT3, respectivamente. O uso de um surfactante aniônico, como o dodecil sulfato de sódio, no preparo de membranas de poli(fluoreto de vinilideno) apresenta-se como uma inovação tecnológica. O uso de diferentes não-solventes alterou a taxa de precipitação do polímero, o que ocasionou alterações na estrutura química, morfológica, cristalina e nas propriedades de transporte das membranas. Análises de microscopia eletrônica de varredura e porosimetria de deslocamento líquido-líquido mostraram a obtenção de estruturas assimétricas, com poros na ordem de 1-2 nm para as membranas MT1 e MT2, e estrutura simétrica, com alta porosidade, para a membrana MT3. A análise de espectroscopia de infravermelho com transformada de Fourier mostrou a presença das fases cristalina α e β nas três membranas e no polímero. Análise termogravimétrica realizada em atmosfera inerte apresentou massa residual em torno de 20-30 % referente ao material carbonáceo, o qual foi eliminado com a utilização de atmosfera oxidante na análise. Os valores de cristalinidade aparente, do polímero e das membranas, apresentaram grandes variações quando determinados pela técnica de calorimetria exploratória diferencial, porém quando determinados a partir dos difratogramas obtidos pela técnica de difração de raios X, a variação foi pequena, apresentando valores em torno de 47%. A avaliação da composição química da superfície das membranas, por espectroscopia de fotoelétrons induzidos por raio X, mostrou que houve variação na quantidade de ligações C-F quando diferentes não-solventes foram utilizados. Essas variações contribuíram para alterações na hidrofobicidade das membranas. As membranas MT1 e MT2 apresentaram características hidrofílicas, com ângulo de contato em torno de 70°, e a membrana MT3 apresentou característica hidrofóbica, com ângulo de contato em torno de 142°. A maior hidrofobicidade da membrana MT3 é resultante da rugosidade superficial e da maior composição relativa de ligações C-F na superfície desta membrana. Ensaios de permeação realizados até a pressão de 20 bar mostraram que a membrana MT2 sofreu maior efeito de compactação e apresentou menor fluxo de permeado. Os ensaios realizados com soluções de cloreto de sódio, de cálcio e férrico mostraram diferentes eficiências de retenção. Para as membranas MT1 e MT2 a retenção de sais mono e divalentes foi praticamente igual, em torno de 5%. Para a solução de cloreto férrico, a retenção apresentou valores médios em torno de 16% e 27% para as membranas MT1 e MT2, respectivamente. Em função do tamanho de poros apresentados e da pressão transmembrana aplicada nos ensaios de permeação, as membranas MT1 e MT2 podem ser utilizadas em processos de nanofiltração. / The search for increasingly efficient technologies in water and effluent treatment made the development of membranes take on an important role in separation processes. The nanofiltration is presented as a promising technology for removal of multivalent salt in aqueous solution. The polymeric membranes preparation by phase inversion technique allows the obtaining of different structures. This study evaluated the use of different nonsolvents in the poly(vinylidene fluoride) membrane preparation, by phase inversion method, on the structural characteristics and functional properties. Were used as nonsolvents: distilled water, solution of sodium dodecyl sulfate and ethanol/water, resulting in the membranes called MT1, MT2 and MT3, respectively. Use of an anionic surfactant, like as sodium dodecyl sulfate, in the preparation of poly(vinylidene fluoride) membranes is presented as a technological innovation. The use of different non-solvents changed the rate of polymer precipitation which caused changes in chemical, morphology and crystalline structures, and transport properties of the membranes. Scanning electron microscopy and liquid-liquid displacement porosimetry analysis showed asymmetric structures, with pores on the order of 1-2 nm for the MT1 and MT2 membrane, and symmetrical structure, with a high porosity for MT3 membrane. The analysis by Fourier transform infrared spectroscopy showed the presence of α and β crystalline phases in the three membranes and in the polymer. Thermogravimetric analysis carried out in an inert atmosphere showed residual mass around 20-30% from the carbonaceous material, which was eliminated with the use of an oxidizing atmosphere in the analysis. The values of apparent crystallinity of the polymer and the membranes showed large variations, by differential scanning calorimetry technique, but when determined from the diffractograms obtained by X-ray diffraction technique, the variation was small, showed values around 47%. The evaluates of the membranes chemical surface composition by X-ray photoelectron spectroscopy showed that there was variation in the amount of C-F bonds, where different non-solvents were used. These variations contributed to changes in membranes hydrophobicity. The MT1 and MT2 membranes showed hydrophilic characteristics with contact angle around 70°, and the MT3 membrane showed hydrophobicity characteristics with contact angle around 142°. The highest hydrofobicity of the MT3 membrane is result of the surface roughness and the relative composition of CF bonds on this membrane surface. Permeation tests performed until a pressure of 20 bar, it was found that the MT2 membrane has a greater effect compression and showed a lower permeate flux. Tests conducted with solutions of sodium, calcium and ferric chloride showed different retention efficiencies. For MT1 and MT2 membranes the retention of mono and divalent salts was practically equal, around 5%. For the solution of ferric chloride, the retention showed medium values around 16% and 27% for the MT1 and MT2 membranes, respectively. Due to the pore size presented and transmembrane pressure applied on permeation tests, the MT1 and MT2 membranes may be used in nanofiltration processes.
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Modelos matemáticos para dispersão de poluentes : análise temporal da dispersão de esgotos descartados em trechos urbanos do rio CapibaribeCarvalho Filho, Ormiro Joaquim de 12 December 2009 (has links)
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Previous issue date: 2009-12-12 / The increasing uncontrolled groundwater exploitation has been the source of many contamination and subsequent degradation problems of such systems. Techniques that
allow an effective and accurate prediction of the effects over time arising from the introduction of pollutants at certain points of a system are essential for developing public policies for them sustainable exploitation, as well as for developing remediation methods and recovery of degraded areas. Therefore, the objective of this dissertation is to create a streamlined system for managing underground water, allowing the zoning of the capture points from Boa Viagem underground area, find out the geographical and temporal evolution of possible indoor pollutants. In the temporal evolution of the dispersion, degradation or accumulation of pollutants, allowing the manager of water resources to create scenarios for
the prevention or recovery from degradation. The mathematical model proposed here will be applied to contribute to the knowledge of pollutants dispersion that may contaminate the Boa Viagem aquifer in this basin in Recife and the metropolitan area / A exploração crescente e desordenada de águas subterrâneas tem sido fonte de diversos problemas de contaminação e posterior degradação de tais sistemas. Técnicas que
permitam uma previsão efetiva e precisa dos efeitos ao longo do tempo oriundos da introdução de poluentes em pontos determinados de um sistema são, desta forma, fundamentais para elaboração de políticas públicas de exploração sustentável dos mesmos, bem como para elaboração de metodologias de remediação e recuperação de áreas já
degradadas. Portanto, o objetivo desta dissertação é gerar um sistema simplificado de gestão hídrica subterrânea, possibilitando o zoneamento dos pontos de captura de água na
bacia hidrográfica subterrânea de Boa Viagem, determinar a evolução geográfica e temporal eventual de poluentes domésticos. Além da evolução temporal da dispersão, degradação ou acúmulo de poluentes, possibilitando ao gestor do recurso hídrico criar cenários de prevenção ou recuperação da degradação. A modelagem matemática aqui proposta será
aplicada na dispersão de poluentes que possam contaminar o aquífero de Boa Viagem presente na bacia hidrográfica do Recife e região metropolitana
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Modelos matemáticos para dispersão de poluentes : análise temporal da dispersão de esgotos descartados em trechos urbanos do rio CapibaribeMelo, Ridelson Tavares de 10 December 2009 (has links)
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Previous issue date: 2009-12-10 / It is undeniable that the advancement of technology and industrial development comes from this bring many benefits to humanity, especially with regard to improvement in quality of life of the general population. Indeed, such advances are such present in modern life that it is difficult to imagine life without some of these, such as electricity and water widely available, sanitation and distribution systems and transportation.While most of the human population is distributed in large urban centers, the growing demand for non-renewable resources such as water and energy seems to be a global trend in the short term and irrevocable. Even in agricultural centers, the introduction of mechanization and practices such as irrigation extend the speed of growth of demand for these resources.Moreover, the overall picture does not appear promising since, to meet growing demand from a growing human population also more than six billion people, you can count on only 0.02% of available water on the planet: that which is in direct use of scenarios such as rivers, lakes and underground reservoirs affordable.To make the situation even worse, consider is the fact that the same overall picture indicates strong growth in the rate of degradation generating, so influenced mainly by new realities weather also imposed by human action, a growing scarcity of the resource.ln this context, Brazil is the only one time, a privileged position and risk with respect to global scenario. Indeed, Brazil has 12 river basin having one of the largest global availability of drinking water or easy treatment, however, given that the rate of urbanization in some of these basins be over 90% and that less than 20% of urban domestic sewage passes through some type of treatment before final disposal in a river or the ocean, such basins are being rapidly degraded and, in a few years, some of them may become viable for human consumption or agricultural use.Thus, the main problems to be addressed by mechanisms for management of water resources are: The subsequent degradation and pollution of water available in different river basins and the management of competition for appeal.Mathematical models suitable for modeling real dynamic systems can contribute as a tool for decision-making measures that regarded water quality. The improvement of mathematical models in urban hydrology, contributes to the reduction of uncertainties in the diagnostic studies of existing systems, design and dimensioning of solutions to pollution. Given therefore that the major cause of pollution direct a spring water flows from the improper disposal of urban waste health, this research project aims to carry out the mathematical modeling of such Descartes allowing the generation of various scenarios and development based on these scenarios, public policies for managing water, the level of pollution control and generation of acts of violation. This model should be immediately applicable - and even be calibrated by data from the historical series of measurements available on the consultation CPRH - to specific parts of the water system composed of the urban sections of rivers Beberibe and Capibaribe in excerpts to be selected by criteria described over design / É inegável que o avanço da tecnologia e o desenvolvimento industrial advindo deste trazem inúmeros benefícios para a humanidade, sobretudo, no que se refere à melhoria na qualidade de vida da população em geral. De fato, tais avanços são de tal ordem presentes na vida moderna que se torna difícil imaginar a vida sem alguns destes como, por exemplo, energia elétrica e água, amplamente disponíveis, saneamento básico e sistemas de distribuição e transporte, ainda que a maior parte da população humana se distribua em grandes centros urbanos, o crescimento demanda de recursos não renováveis tais como água e energia que parecem ser uma tendência mundial e irrevogável no curto prazo. Mesmo nos centros agrícolas, a mecanização e a introdução de práticas como a irrigação ampliam a velocidade de crescimento da demanda de tais recursos.Por outro lado, o cenário global não parece promissor uma vez que, para suprir a demanda crescente de uma população humana também crescente de mais de seis bilhões de habitantes, pode-se contar com apenas 0,02% da água disponível no planeta: aquela que se encontra em cenários de uso direto tais como rios, lagos e reservatórios subterrâneos economicamente acessíveis. Para agravar tal situação, considere-se o fato de que o mesmo cenário global indica forte crescimento da velocidade de degradação; gerando, de forma influenciada, sobretudo por novas realidades climáticas impostas também pela ação humana, uma crescente escassez deste recurso. Nesse contexto, o Brasil encontra-se, a um só tempo, em posição privilegiada e de risco com relação ao cenário global. Com efeito, o Brasil possui 12 regiões hidrográficas possuindo uma das maiores disponibilidades mundiais de água potável ou de fácil tratamento, contudo, dada que a taxa de urbanização em algumas destas bacias é superior a 90% e que menos de 20% do esgoto urbano nacional passa por algum tipo de tratamento antes do descarte final em algum rio ou no oceano, essas bacias estão sendo rapidamente degradadas e, no decurso de poucos anos, algumas delas podem se tornar inviáveis para o consumo humano ou utilização agrícola. Dessa forma, os principais problemas a serem tratados pelos mecanismos de gestão de recursos hídricos são: a poluição e posterior degradação da água disponível nas diferentes bacias hidrográficas e o gerenciamento da competição pelo recurso. Modelos matemáticos adaptados a modelagem de sistemas dinâmicos reais podem contribuir como ferramenta de tomada de decisão para medidas que resguardem a qualidade da água. O aprimoramento de modelos matemáticos, em hidrologia urbana, contribui para a redução de incertezas em estudos de diagnóstico de sistemas existentes, de concepção e de dimensionamento de soluções de poluição. Dado, portanto, que a maior causa de poluição direta de mananciais hídricos decorre do descarte inadequado de resíduos sanitários urbanos. Este projeto de pesquisa tem por objetivo realizar a modelagem matemática de tais descartes possibilitando a geração de cenários diversos e a elaboração baseada em tais cenários de políticas públicas de gerenciamento hídrico, controle do nível de poluição e geração de atos de infração. Tal modelo deve ser imediatamente aplicável - e será inclusive calibrado por dados da série histórica de medições disponíveis sob consulta a CPRH - a partes específicas do sistema hídrico composto pelos perfis urbanos dos rios Capibaribe e Beberibe em trechos a serem selecionados mediante critérios descritos ao longo do projeto
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Otimização do tratamento de águas oleosas com alto grau de emulsificação utilizando biossurfactante e flotação por ar dissolvido (fad).Lins, Josiane Maria de Santana Melo 23 March 2017 (has links)
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Previous issue date: 2017-03-23 / Residual Frying Oil (RFO) is part of one of the waste generated daily in households,
industries and voluntary delivery points (public and mixed-economy companies). The
uncontrolled disposal of residues of frying oils, in sinks or dumped directly into
bodies of water, entails a series of environmental damages, such as obstruction of
pipes in sewage systems and increased costs of treatment processes, in addition to
Increased pollution. The collection and reuse of these waste oils prevents them from
being disposed of inappropriately and benefits the environment. The percentage
recovery of residual oil from fried foods depends to a large extent on the washing
operations. These operations are also responsible for the effective separation of the
organic and aqueous phases from the emulsions generated so as to obtain a lower
possible oil content in the aqueous phase, while the oil can still be used for reuse in
the soap and detergent production processes. In this work, actions were taken to
improve the operational conditions to improve the process of chemical washing of
the ORF by cleaning products industries, in order to generate an adequate effluent
for subsequent physical-chemical treatment by Dissolved Air Flotation (DAF). After
conditioning, the OFR collection vessel was rinsed with steam and received addition
of chemical reagents (HCLO3, NaOH and NaCl). The material was then treated
through DAF, with a biosurfactant acting as a biodegradable manifold, in a
laboratory scale prototype operating in continuous mode. The experiments were
performed according to a Central Composite Designs (CCD) of type 22. As factors,
the ratio between the effluent flow to be treated and the biosurfactant flow rate (X1)
was used, and the ratio of the air flow to the effluent flow recirculated to produce the
microbubbles (X2). As a response variable the water-oil separation efficiency was
used. A maximum separation efficiency of 98.0% for X1 and X2 values equal to
1.0.103 and 1.05.104, respectively. / O Óleo de Fritura Residual (OFR) é parte de um dos resíduos gerados diariamente
em residências, indústrias e pontos de entrega voluntários (empresas públicas e de
economia mista). A eliminação descontrolada de resíduos de óleos de fritura, em
sumidouros ou jogados diretamente em corpos d’água, acarreta uma série de danos
ambientais, tais como a obstrução de tubos em sistemas de esgotos e o aumento
dos custos dos processos de tratamento, além do aumento da poluição. O
recolhimento e a reutilização desses óleos usados impede o seu descarte
inadequado e traz benefícios para o ambiente. A percentagem de recuperação de
óleo residual proveniente de alimentos fritos depende, em grande parte, das
operações de lavagem. Estas operações são também responsáveis pela separação
efetiva das fases orgânicas e aquosa das emulsões geradas, de forma a se obter um
menor teor de óleo possível na fase aquosa, enquanto que o óleo possa ainda ser
utilizada para reúso nos processos produtivos de sabões e detergentes. Neste
trabalho, foram realizadas ações para melhorar as condições operacionais de
aprimoramento do processo de lavagem química do ORF por indústrias de produtos
de limpeza, a fim de gerar um efluente adequado para posterior tratamento físicoquímico
por Flotação de Ar Dissolvido (FAD). Depois de acondicionado, o recipiente
de coleta de OFR foi lavado com vapor e recebeu adição de reagentes químicos
(HCLO3, NaOH e NaCl). O material foi então tratado através de FAD, com um
biossurfactante atuando como um colector biodegradável, num protótipo de escala
laboratorial operando em modo contínuo. Os experimentos foram realizados de
acordo com um Delineamento Composto Central Rotacional (DCCR) do tipo 22.
Como fatores utilizou-se a razão entre a vazão do efluente a ser tratado e a vazão
de biossurfactante (X1), e a razão entre a vazão de ar e a vazão de efluente
recirculada para produzir as microbolhas (X2). Como variável resposta utilizou-se a
eficiência de separação água-óleo. Uma eficiência máxima de separação de 98,0 %
para valores de X1 e X2 iguais a 1,0.103 e 1,05.104, respectivamente.
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Developing a second, third, and fourth grade environmental unit on water educationPrice, Denise M. 01 January 1991 (has links)
No description available.
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