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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Treatment Process Variations to Reduce TTHM Residuals in a Finished Water

Hatcher, Edward L. 01 July 1979 (has links) (PDF)
This research investigates organic polymers, inorganic coagulants and separate unit operations for their effect on the total tri-halogenated (TTHM) residuals in a finished water. The water samples utilized for this project were taken from a highly colored Central Florida potable water supply which is used by municipality which has a TTHM concentration in the finished water in excess of the proposed Federal limit. Results indicate that (1) organic polymers are not a significant source of THM precursors, (2) organic polymers, when used as a settling aid after coagulation in Jar tests, are an effective means of filtration for removing THM precursors, (3) THM residuals produced after coagulation increased directly with chlorination pH, (4) there was no significant difference in the THM precursor removal after coagulation for any coagulant tested and (5) coagulation removed a significant amount of THM precursor from the raw water.
2

DEVELOPMENT AND COMPARISON OF LINEAR AND NONLINEAR MULTIPLE REGRESSION MODELS FOR PREDICTING TRIHALOMETHANE FORMATION KINETICS.

Chowdhury, Zaid Kabir. January 1984 (has links)
No description available.
3

The prediction of chlorine decay from potable water in pipeline systems

Viljoen, Ockert Jacobus 22 August 2012 (has links)
M.Ing. / The modelling of water quality in distribution systems is a relatively new field. It has become necessary to attend to the problem of water quality at the consumer's tap because water quality after treatment is not a guarantee for the water that reaches the consumer. It is increasingly important to design and manage distribution systems carefully to ensure safe drinking water up to the consumer's tap. This report gives the results and a discussion thereof on the chlorine decay in laboratory batch tests as well as on pipeline systems. Significant contributions were made to the different objectives of the study. Standardised test procedures for both free chlorine and monochloramine were developed. It was found that the n th-order, 1 parameter model described the decay of chlorine significantly better than did the generally assumed first order mathematical model. It was also found that the reaction orders are different for different water sources, and even different for the same water source at different times. It was also clear that the rate constants are dependent on temperature - the higher the temperature, the higher the decay rate constants. The reaction order for free chlorine varied from 0.36 to 1.22 with no apparent underlying pattern. For monochloramine, the reaction order fell into two distinctively different categories. For monochloramine decay up to 24 hours, the reaction order varied from 0.02 to 0.05. For monochloramine decay from 24 hours onwards, the reaction order varied from 0.92 to 0.95. As was expected, the free chlorine decay rates obtained in pipelines were higher than in parallel bulk decay rate tests. On the assumption that the bulk decay reaction order is equal to one, the mass transfer coefficient between the bulk flow and the pipe wall varied between 0.0065 m/h and 0.0457 m/h. Further research is highly recommended on the effect of secondary and tertiary chlorination as well as on more direct methods of estimating pipe wall-related chlorine reaction constants.
4

Nominal Molecular Weight Distributions of Color, TOC, TTHM, Precursors and Acid Strength in a Highly Organic Potable Water Source

Fouroozi, Jalil 01 January 1980 (has links) (PDF)
This research investigated the relationships between molecular size and the TOC, TTHM, acid strength and color concentrations present in raw and coagulated water from Lake Washington. Three separate coagulants were utilized for investigation. There were: Al, Fe and Mg. Results indicated that the majority of the TOC, color and TTHM precursors were in the colloidal size range and removed by coagulation. The remaining TTHM precursors are mostly molecular and require a process other than coagulation for removal from the potable water before environmental standards are met.
5

Best practices in drinking water quality regulation elements of an Australian model

Moeller, Anthony. January 2001 (has links) (PDF)
Includes bibliographical references (p. 319-347) Mode of access: Internet via World Wide Web. Available at: http://business.unisa.edu.au/waterpolicylaw/documents/thesis.pdf Selected for archiving SSL
6

A review of drinking water management in Hong Kong

So, King-lung, Benny., 蘇景隆。. January 1999 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
7

Silver nanoparticle-resin filter system for drinking water disinfection and inhibition of biofilm formation.

Mpenyana-Monyatsi, Lizzy January 2013 (has links)
D. Tech. Water care. / Groundwater is the main source of drinking in most rural areas of South Africa and is supplied to the communities without prior treatment. However, the contamination of groundwater sources by pathogenic bacteria poses a public health concern to these communities. This study was aimed at developing and evaluating the effectiveness of filter materials coated with silver nanoparticles for the removal of pathogenic microorganisms from groundwater as well as the inhibition of biofilm formation in drinking water systems.
8

"Avaliação do impacto de agrotóxicos em áreas de proteção ambiental, pertencentes à bácia hidrográfica do Rio Ribeira de Iguape, São Paulo. Uma contribuição à análise crítica da legislação sobre o padrão de potabilidade" / ASSESSMENT OF THE IMPACT OF PESTICIDES IN ENVIRONMENTAL PRESERVATION AREAS FROM RIBEIRA DE IGUAPE RIVER, SÃO PAULO. CRITICAL CONTRIBUTION TO THE GUIDELINES FOR DRINKING-WATER STANDARDS.

Marques, Maria Nogueira 11 February 2005 (has links)
No presente trabalho estudou-se a qualidade de recursos hídricos na Bacia Hidrográfica do Rio Ribeira de Iguape, localizada na região sudeste do estado de São Paulo. Esta é a única bacia no estado de São Paulo onde a relação disponibilidade de água versus demanda é extremamente positiva. Na região está localizada a maior concentração de Mata Atlântica do país. Atualmente, a agricultura é a principal atividade econômica, destacando-se as culturas do chá e da banana. Avaliou-se o impacto da atividade agrícola na qualidade da água por meio da caracterização da água em áreas de captação superficial e da água destinada ao abastecimento público. Realizou-se uma análise de risco do potencial de contaminação por agrotóxicos em águas superficiais e subterrâneas, analisando as características físico-químicas dos princípios ativos, dos produtos utilizados na região, relacionando-as com os aspectos básicos de meteorologia, hidrologia e características do solo. Realizaram-se 6 campanhas, sendo 5 campanhas no período de março de 2002 a fevereiro de 2003 e uma em janeiro de 2004, em 10 municípios situados ao longo do Rio Ribeira de Iguape e seus principais afluentes. Avaliaram-se os resíduos dos carbamatos (aldicarbe, carbofurano e carbaril), das triazinas (simazina e atrazina) e da nitroanilina (trifluralina) utilizando-se o método por extração em fase sólida e análise por cromatografia líquida de alta eficiência acoplada ao detector UV/visível (SPE-LC-UV/vis). Verificou-se que a qualidade da água está relacionada com os períodos de chuva e seca. No início do período chuvoso, observou-se um número maior de amostras positivas com os resíduos de agrotóxicos bem como maior variabilidade nos parâmetros físico-químicos, das amostras de água superficial, devido ao alto índice pluviométrico da região que aumenta a lixiviação do solo. Do total de 152 amostras analisadas somente 24% apresentaram resíduos agrotóxicos. Desenvolveu-se uma metodologia para determinação de carbamatos, atrazinas e triazinas por extração em fase sólida e análise por cromatografia líquida de alta eficiência acoplada ao detector espectrometria de massas Tandem (SPE-LC-MS/MS). O método mostrou-se eficiente na determinação destes compostos,apresentando ótima sensibilidade e seletividade. Aplicou-se o método nas amostras coletadas em janeiro de 2004 e devido a sua sensibilidade, o carbofurano foi identificado nas 20 amostras analisadas, sendo que em três das amostras de água tratada apresentou o produto de degradação, 3–OH–carbofurano. Verificou-se que a Bacia já apresenta indícios de uso de agrotóxico na agricultura, embora, as concentrações observadas não comprometam a qualidade da água para o abastecimento humano. Realizou-se uma avaliação crítica da legislação vigente pertinente (Portaria no 518/MS/04) e sua comparação com normas e legislações, tanto nacionais quanto internacionais. Discutiu-se a sua aplicação a partir de critérios tais como prazo legal de cumprimento, facilidade e dificuldades técnicas (análises físico-químicas, ensaios acreditados e logísticas) e custos. / This research was focused on the assessment of the water quality of Ribeira de Iguape River Basin, located in the Southeastern region of São Paulo State, where the ratio of water availability against demand is high. Reminiscent of Atlantic Forest represents high occupation of this area in Brazil. Agriculture is the main economic activity in the region, with tea and banana as the main crops. The impact of agricultural activities on the environment has been characterized in both the surface water areas of catchments and drinking water. For superficial and underground waters, risk analysis of the contamination by pesticides was carried out, correlating the physicochemical properties of the active compounds used in the region with some basic aspects of meteorology, hydrology and soil characteristics. Water samplings were carried out during the period March/2002 -February/2003, and during January/2004 in 10 different catchments points along River Ribeira de Iguape and its main tributaries. Solid-phase extraction followed by high performance liquid chromatography coupled with UV/Vis detection (SPE-LC-UV/vis) was used as an analytical method to monitor various classes of pesticides such as carbamates (aldicarb, carbofuran and carbaryl), triazines (simazine and atrazine), and nitroanilines (trifluralin). The results revealed that the water quality is associated with the season of rains and dries. Due to the high precipitation index in the beginning of the rainy season, pesticide residues were found in most samples, and high variability in their physicochemical properties was observed. Form 152 samples analyzed, only 24% showed the presence of pesticide. The specificity and sensitivity in the pesticides analyses was enhanced by a methodology employing solid-phase extraction followed by high performance liquid chromatography coupled with tandem mass spectrometry (SPE-LC-MS/MS). Specifically, this method was applied to all samples collected in January of 2004. Carbofuran and its metabolite 3-OH-carbofuran were detected in 20 and three of the samples, respectively. Although the observed low pesticide concentrations should not compromise the water quality for drinking, the present work demonstrates the impact of pesticides use in agriculture. In a complementary study, the current guidelines for drinking-water standards (no 518/MS/04) were critically evaluated and discussed by comparing national and international rules and regulations. Technical applicability of the legislation, the difficulty to comply with the imposed deadlines, and the costs of attending such requisites has been further discussed, as well.
9

"Avaliação do impacto de agrotóxicos em áreas de proteção ambiental, pertencentes à bácia hidrográfica do Rio Ribeira de Iguape, São Paulo. Uma contribuição à análise crítica da legislação sobre o padrão de potabilidade" / ASSESSMENT OF THE IMPACT OF PESTICIDES IN ENVIRONMENTAL PRESERVATION AREAS FROM RIBEIRA DE IGUAPE RIVER, SÃO PAULO. CRITICAL CONTRIBUTION TO THE GUIDELINES FOR DRINKING-WATER STANDARDS.

Maria Nogueira Marques 11 February 2005 (has links)
No presente trabalho estudou-se a qualidade de recursos hídricos na Bacia Hidrográfica do Rio Ribeira de Iguape, localizada na região sudeste do estado de São Paulo. Esta é a única bacia no estado de São Paulo onde a relação disponibilidade de água versus demanda é extremamente positiva. Na região está localizada a maior concentração de Mata Atlântica do país. Atualmente, a agricultura é a principal atividade econômica, destacando-se as culturas do chá e da banana. Avaliou-se o impacto da atividade agrícola na qualidade da água por meio da caracterização da água em áreas de captação superficial e da água destinada ao abastecimento público. Realizou-se uma análise de risco do potencial de contaminação por agrotóxicos em águas superficiais e subterrâneas, analisando as características físico-químicas dos princípios ativos, dos produtos utilizados na região, relacionando-as com os aspectos básicos de meteorologia, hidrologia e características do solo. Realizaram-se 6 campanhas, sendo 5 campanhas no período de março de 2002 a fevereiro de 2003 e uma em janeiro de 2004, em 10 municípios situados ao longo do Rio Ribeira de Iguape e seus principais afluentes. Avaliaram-se os resíduos dos carbamatos (aldicarbe, carbofurano e carbaril), das triazinas (simazina e atrazina) e da nitroanilina (trifluralina) utilizando-se o método por extração em fase sólida e análise por cromatografia líquida de alta eficiência acoplada ao detector UV/visível (SPE-LC-UV/vis). Verificou-se que a qualidade da água está relacionada com os períodos de chuva e seca. No início do período chuvoso, observou-se um número maior de amostras positivas com os resíduos de agrotóxicos bem como maior variabilidade nos parâmetros físico-químicos, das amostras de água superficial, devido ao alto índice pluviométrico da região que aumenta a lixiviação do solo. Do total de 152 amostras analisadas somente 24% apresentaram resíduos agrotóxicos. Desenvolveu-se uma metodologia para determinação de carbamatos, atrazinas e triazinas por extração em fase sólida e análise por cromatografia líquida de alta eficiência acoplada ao detector espectrometria de massas Tandem (SPE-LC-MS/MS). O método mostrou-se eficiente na determinação destes compostos,apresentando ótima sensibilidade e seletividade. Aplicou-se o método nas amostras coletadas em janeiro de 2004 e devido a sua sensibilidade, o carbofurano foi identificado nas 20 amostras analisadas, sendo que em três das amostras de água tratada apresentou o produto de degradação, 3–OH–carbofurano. Verificou-se que a Bacia já apresenta indícios de uso de agrotóxico na agricultura, embora, as concentrações observadas não comprometam a qualidade da água para o abastecimento humano. Realizou-se uma avaliação crítica da legislação vigente pertinente (Portaria no 518/MS/04) e sua comparação com normas e legislações, tanto nacionais quanto internacionais. Discutiu-se a sua aplicação a partir de critérios tais como prazo legal de cumprimento, facilidade e dificuldades técnicas (análises físico-químicas, ensaios acreditados e logísticas) e custos. / This research was focused on the assessment of the water quality of Ribeira de Iguape River Basin, located in the Southeastern region of São Paulo State, where the ratio of water availability against demand is high. Reminiscent of Atlantic Forest represents high occupation of this area in Brazil. Agriculture is the main economic activity in the region, with tea and banana as the main crops. The impact of agricultural activities on the environment has been characterized in both the surface water areas of catchments and drinking water. For superficial and underground waters, risk analysis of the contamination by pesticides was carried out, correlating the physicochemical properties of the active compounds used in the region with some basic aspects of meteorology, hydrology and soil characteristics. Water samplings were carried out during the period March/2002 -February/2003, and during January/2004 in 10 different catchments points along River Ribeira de Iguape and its main tributaries. Solid-phase extraction followed by high performance liquid chromatography coupled with UV/Vis detection (SPE-LC-UV/vis) was used as an analytical method to monitor various classes of pesticides such as carbamates (aldicarb, carbofuran and carbaryl), triazines (simazine and atrazine), and nitroanilines (trifluralin). The results revealed that the water quality is associated with the season of rains and dries. Due to the high precipitation index in the beginning of the rainy season, pesticide residues were found in most samples, and high variability in their physicochemical properties was observed. Form 152 samples analyzed, only 24% showed the presence of pesticide. The specificity and sensitivity in the pesticides analyses was enhanced by a methodology employing solid-phase extraction followed by high performance liquid chromatography coupled with tandem mass spectrometry (SPE-LC-MS/MS). Specifically, this method was applied to all samples collected in January of 2004. Carbofuran and its metabolite 3-OH-carbofuran were detected in 20 and three of the samples, respectively. Although the observed low pesticide concentrations should not compromise the water quality for drinking, the present work demonstrates the impact of pesticides use in agriculture. In a complementary study, the current guidelines for drinking-water standards (no 518/MS/04) were critically evaluated and discussed by comparing national and international rules and regulations. Technical applicability of the legislation, the difficulty to comply with the imposed deadlines, and the costs of attending such requisites has been further discussed, as well.
10

Challenges in the delivery of water services in Sekhukhune District Municipality : a case of Makhuduthamaga Local Municipality

Moagi, Percy Kapudi January 2021 (has links)
Thesis (M. Dev. (Planning and Management)) -- University of Limpopo, 2019 / The provision of basic water services delivery to all South African citizens is one of the huge challenges for the local government and it is at the coalface of service delivery. The objective of the study was to determine the factors that influence water service delivery challenges in the local municipality of Makhuduthamaga, in Sekhukhune District Municipality. The statement of the problem, therefore, provided the foundation within which the aims of the study are explained. The significance of this research cannot be over-emphasised, especially against the backdrop that local government is the third sphere of government and is in the front line of service delivery. This study aimed at investigating the water service delivery challenges in the municipality of Makhuduthamaga in Sekhukhune District, Limpopo province. This research was necessitated by the lack of water in Makhuduthamaga Local Municipality. It is evident that there are several challenges in the delivery of water services in the local sphere, however, for the sake of this research only one municipality was selected as a case study. The study employed a qualitative case study research design to collect data from participants who were selected through a purposive sampling technique. The study participants included the local community representatives and the municipal officials responsible for water services in the municipality and the water resources available in the locality such as the Vergelegen, Nkadimeng and De Hoop dams. The finding shows that the available water sources are not adequate to cater for all the residents of the municipality; hence this affects the water delivery efforts of the municipality significantly. As a result, local residents have expressed their dissatisfaction through violent service delivery protests in different wards of the municipality. The study further reveals that the municipality has been facing serious water services challenges over several years. The issue emanates from the water sources which are dried up, illegal connections, incomplete projects by contractors, financial constraints, and poor maintenance planning. The main challenge here is the lack of water sources, poor maintenance, lack of skills and expertise from the employees in the water department, insufficient budget to relieve the water crisis in the municipality and the district at large. The municipality has implemented all the interventions, such as public participation to vi encourage communities to use water sparingly, to pay for services of the municipality for the sake of revenue enhancement and have drilled more boreholes to augment the water services to the communities. This study recommends that the municipality should prioritise their budgeting and align this to the community needs, hiring the correct personnel with relevant skills and expertise in the water related function. Also, the municipality needs to work on the turnaround time for the maintenance of pump stations and fixing of leaking water pipes. They should penalise all the illegally connected households so that they can curb all the recurring illegal connections. The other issue is to improve communications with the communities with relevant stakeholders to ensure that everyone is informed in case of water cuts due to maintenance or cleaning of water reservoirs.

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