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1
Worley, Jennifer Lee. "Evaluation of Dechlorinating Agents and Disposable Containers for Odor Testing of Drinking Water." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/9764.
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As the bottled water trend continues to rise across the nation, drinking water utilities have become more concerned with ensuring consumer satisfaction of their product. Although public water supplies are safeguarded by regulations, aesthetically unappealing taste-and-odor problems have led consumers to search for alternative water sources, such as bottled water or tap water processed by point-of-use filters. Consequently, taste-and-odor monitoring has become important to the drinking water industry. Because many utilities use chlorine to disinfect the water, chlorine odor often masks other more subtle odors that may eventually cause consumer complaints. As treated water travels from the water treatment plant to the consumer, chlorine residual diminishes and may reveal a water's naturally less-pleasing odors. Consequently, odor monitoring at the water treatment plant, where chlorine concentrations are at a peak, may not identify potential displeasing smells. Proper evaluation of these odor-causing substances requires that the chlorine odor first be eliminated before evaluating any remaining odors. Dechlorinating agents can remove chlorine, but some will produce other unwanted odors or even remove certain odorous compounds. This research describes the efficiency of several of these agents (ascorbic acid, hydrogen peroxide, oxalic acid, sodium nitrite, and sodium thiosulfate) in dechlorinating chlorinated solutions of the earthy-smelling compound geosmin and musty-smelling MIB.
Interfering odors in reusable containers pose another problem in drinking water odor analysis. The most common odor-analysis methods (TON and FPA) involve the use of glass flasks, which often either develop chalky odors or have persistent lingering odors from previous evaluations. Furthermore the glass flasks break easily and are difficult to clean. This research also evaluates the suitability of four types of disposable plastic containers for odor analyses.Master of Science
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Sävenhed, Roger. "Chemical and sensory analysis of off-flavour compounds in drinking water." Linköping : Linköping University, 1986. http://catalog.hathitrust.org/api/volumes/oclc/25607250.html.
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Byrd, Julia Frances. "Applications of Sensory Analysis for Water Quality Assessment." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/81969.
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In recent years, communities that source raw water from the Dan River experienced two severe and unprecedented outbreaks of unpleasant tastes and odors in their drinking water. During both TandO events strong 'earthy', 'musty' odors were reported, but the source was not identified. The first TandO event began in early February, 2015 and coincided with an algal bloom in the Dan River. The algal bloom was thought to be the cause, but after the bloom dissipated, odors persisted until May 2015. The second TandO in October, 2015 did not coincide with observed algal blooms.
On February 2, 2014 approximately 39,000 tons of coal ash from a Duke Energy coal ash pond was spilled into the Dan River near Eden, NC. As there were no documented TandO events before the spill, there is concern the coal ash adversely impacted water quality and biological communities in the Dan River leading to the TandO events. In addition to the coal ash spill, years of industrial and agricultural activity in the Dan River area may have contributed to the TandO events.
The purpose of this research was to elucidate causes of the two TandO events and provide guidance to prevent future problems. Monthly water samples were collected from August, 2016 to September, 2017 from twelve sites along the Dan and Smith Rivers. Multivariate analyses were applied to look for underlying factors, spatial or temporal trends in the data.
There were no reported TandO events during the project but sensory analysis, Flavor Profile Analysis, characterized earthy/musty odors present. No temporal or spatial trends of odors were observed. Seven earthy/musty odorants commonly associated with TandO events were detected. Odor intensity was mainly driven by geosmin, but no relationship between strong odors and odorants was observed.Master of Science
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Mann, Georgianna Rhodes. "Effects of mineral content of bovine drinking water: Does iron content affect milk quality?" Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/22018.
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Implications of water chemistry on milk synthesis are not well described yet water is an important nutrient for dairy cattle. High mineral concentrations (>0.3 mg/kg Fe and others) may be associated with natural levels in ground water, contaminating sources, drought conditions, or storage systems. This study evaluated effects of added iron in bovine drinking water on milk composition (Ca, Cu, Fe, P) measured by inductively coupled plasma mass spectrometry and oxidative stability measured by thiobarbituric acid reactive substances assay for malondialdehyde (MDA), volatile chemistry and sensory analysis (triangle test). Prepared ferrous lactate treatments, corresponding to 0, 2, 5, and 12.5 mg/kg drinking water levels were given abomasally (10 L/d) to 4 lactating dairy cows over 4 periods (1 wk infusion/period) in a Latin square design. Milk was collected (d6 of infusion), processed (homogenized, pasteurized), and analyzed within 72 h of processing and 7 d of refrigerated storage. No differences in MDA (1.46�0.04 mg/kg) or iron (0.22�0.01 mg/kg) were observed in processed milk. Cross effects analysis (treatment*cow) showed significant differences in calcium, copper and iron (P < 0.05). Sensory differences (P < 0.05), in treatment vs. control, suggested iron from water sources contributes to milk flavor changes. A case study with high and low (0.99; 0.014 mg/kg) iron treatments revealed no significant differences (P > 0.05) in mineral composition (0.23�0.06 mg/kg Fe) or MDA (0.77�0.03 mg/kg) of raw milk. Iron added to milk causes changes in oxidation; high levels of iron in bovine drinking water may not have observed effects.Master of Science in Life Sciences
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Forsberg, Agnes. "Evaluation of drinking and irrigation water quality in Njuli, Malawi." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-236643.
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Good water quality is very central to a country's wellbeing. Clean water is required to ensureboth the health of the population and good ecological status of the country. It is thereforeimportant to continually conduct surveys to determine the status of the water used in, forexample, households, industries and agriculture.Elevated levels of metals, sulphate, nitrate and phosphate in drinking water can lead to poorhealth through consumption and reduced harvest when the water is used in irrigation.This report aimed at examining whether the water resources available in the vicinity of Njuliquarry in Chiradzulo, Malawi, meet the requirements of drinking and irrigation water. Thestudy found that most of the studied parameters were within the recommendations set by theMalawi Bureau of Standards (MBS) and the World Health Organization (WHO). However,conductivity in some of the water samples was higher than the recommendations. Both nitrateand iron concentrations were higher than recommended at a few locations.The study cannot conclude that the water from the water sources near the Njuli quarry containharmful levels of metals, nitrate, sulfate or phosphate.
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Durand, Monique Lucia. "Disinfectants and Plumbing Materials: Effects on the Sensory and Chemical Characteristics of Drinking Water." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/35861.
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The distribution system is the primary cause of taste and odor complaints in drinking water. This research examined the ability of small diameter pipes used in home plumbing to affect drinking water quality. The properties of the materials were investigated in the absence of disinfectant and the presence of either chlorine or chloramines. A panel was trained in flavor profile analysis (FPA) according to Standard Methods 2170B and used to assess the sensory properties of all samples. Chemical analyses were performed to determine disinfectants, total organic carbon (TOC), pH and specific organic contaminants.
The first part of this study investigated PEX pipes manufactured by the silane (PEX-b) and peroxide (PEX-a) cross-linking technology, using the utility quick test (UQT) method. Silane PEX-b had a greater effect on water quality properties such as odor, TOC and residual disinfectant demand than peroxide-linked PEX-a. Chemical analysis revealed that PEX pipes can contribute fuel oxygenates such as ETBE (PEX-b) and possibly MTBE (PEX-a) to drinking water. PEX pipes did not contribute any significant trihalomethanes to drinking water. This study showed that the type of PEX used in homes will determine the extent to which drinking water quality is affected.
The second part of this study used simulated plumbing rigs to investigate seven different materials under low flow and stagnant conditions; chlorinated polyvinyl chloride, cross-linked polyethylene, polyethylene, epoxy-lined copper, copper, stainless steel, galvanized iron and glass (control). Results showed that these plumbing materials have the potential to affect water quality characteristics such as TOC concentrations, residual disinfectant and odor when newly installed in homes. A high TOC concentration was consistent with the presence of a distinct odor or a high FPA intensity rating. Galvanized iron produced the worst odors that were consistently described as "motor oil". Polyethylene generated more intense plumbing associated odors than PEX or cPVC plastic material. cPVC and copper generated the least odors. Both copper pipe and epoxy-lined copper consumed residual chlorine and chloramines.Master of Science
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Kerwick, Mark Ian. "An evaluation of alternative technologies for drinking water disinfection." Thesis, University of Surrey, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.594172.
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A methodology has been developed and used to evaluate the alternatives to chlorination for primary and residual drinking water disinfection. From the evaluation process it was concluded that at present none of the altemalives could viably replace chlorination for both primary and residual disinfection. The study did however highlight the potential of electrochemical disinfection technologies to provide primary and residual disinfection in the future by the generation of a range of oxidants including chlorine species. Hence, three electrochemical technologies (a mixed oxidant generator, a direct electrolyser with carbon aerogel electrodes, and a direct electrolyser called Zappi ™ )were chosen to assess their potential as an alternative to conventional chlorination for primary and residual disinfection. The disinfection efficiencies of the three devices were assessed. Anolyte produced from the mixed oxidant generator was compared directly with hypochlorite at equal doses. Anolyte was shown be more effective against E. coli, reducing the E. coli count by >6 logs and to have the same potential for trihalomethane formation in slow sand filtered water, generating 30).μg/L when dosed at lmg/L for 24 hours. The carbon aerogel and Zappi™ direct electrolysers were shown to disinfect E. coli in a range of electrolytes and water matrices. Total measurable E. coli log reductions were achieved in both devices using a chloride electrolyte. Significantly, both devices were effective against E. coli in sulphate electrolytes without the generation of chlorine, with 3 and 4 log reductions respectively. The carbon aerogel device was also shown to be effective in a good quality sewage effluent matrix and tap water reducing E. coli by >4 logs. Whilst, the Zappi was shown to reduce E. coli by >2 logs in slow sand filtered water. Phosphate was shown to significantly reduce disinfection in both direct devices. The effectiveness of the direct electrolysers was shown to be variable against other micro-organisms. The Zappi™ device was effective against the virus, bacteriophage MS2 in a sulphate electrolyte, with a >5 log inactivation after 30 minutes. Whilst, the carbon aerogel device achieved a > 1 Jog reduction of Enterovirus after 40 minutes in tap water and a 2 log reduction of Cryptosporidium oocysts in tap water. It should be noted that the reduction in Cryplosporidium could be attributable to removal via filtering rather than inactivation by oxidant attack. Possible mechanisms for electrochemical disinfection were investigated of these oxidant generation was shown t~ be responsible for disinfection_ Determination of the oxidant species generated proved to be problematic. The presence of chlorine and the high voltages used in all three devices made it difficult to isolate specific oxidants. The bactericidal properties of two poly-viologens were assessed 10 determine their potential for mediating oxidant generation for drinking water disinfection. The poly-viologens were shown to reduce the E. coli count by 6 logs. However, the results were inconclusive due to the variability between poly-viologen batches. These studies do however infer that poly-viologens may still have a future use as oxidant mediators in disinfection devices.
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Liu, Xibo. "Drinking water biofiltration, assessing key factors and improving process evaluation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ60553.pdf.
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Sain, Amanda Elizabeth. "Aerosolization of Drinking Water Metals to Indoor Air and Assessment of Human Taste and Visual Thresholds for Manganese." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/50558.
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Exposure to excess manganese via drinking water raises concerns due to potential for adverse neurological impacts, particularly in children. Manganese is ubiquitous in US groundwaters above the SMCL = 0.05 mg/L. Manganese is an essential nutrient, but exposures to elevated manganese have neurotoxic effects. Chapter 2 focuses on human senses\' ability to detect manganese in drinking water. Findings indicate human senses cannot be relied upon to detect excess Mn(II) in drinking water. Mn(IV) is easily visually detected, but cannot be tasted at 10 times the SMCL. Chapter 3 is an assessment the ability of an ultrasonic humidifier to expel drinking water impurities in aerosols. The quality of the water used to charge the humidifier reservoir affects the composition of elements in the aerosols and condensate. Findings indicate condensed humidifier aerosols contain 85% of elements present in the reservoir water for a variety of water types if there is no precipitation. Waters with high concentration of hardness or iron formed precipitates that decreased the concentrations of these metals in the aerosols causing variable results for other elements that were initially present at < 1mg/L in the charge water. This indicates that humidifiers could be a source of inhalation exposure for source water contaminants.Master of Science
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Puget, Sabine. "Chlorine flavor perception and neutralization in drinking water." Phd thesis, Université de Bourgogne, 2010. http://tel.archives-ouvertes.fr/tel-00786522.
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For water suppliers, using chlorine is necessary to ensure water bacteriological quality from the treatment plant to the consumers' tap. However, chlorine flavour is one of the most common reasons advocated for choosing tap water alternatives as drinking water. As a consequence, the putative link between chlorine flavour perception and tap water consumption is an issue in drinking water habits studies. Since the sensory mechanisms involved in chlorine flavour perception remained largely unknown, the main objective of this thesis work was to first highlight those mechanisms and then to identify potential lever chlorine flavour sensory neutralisation.In a first step, we demonstrated that hypochlorous acid associated, which is likelyresponsible of chlorine flavour in tap water, could activate the olfactory system at low concentrations and the trigeminal system for concentrations up to 4 mg/L Cl2. Additionally, our results suggested that tap water consumption does not seem to be related to sensitivity to chlorine flavour but rather to consumers' tap water representation.In a second stage, we explored the impact of water mineral matrix on chlorine flavour perception. We demonstrated first that water molarity and cationic content variations modulate drinking water taste. We also evidenced that chlorine flavour intensity is modulated according to water composition. Nevertheless, our data suggest that physico-chemical, in- mouth physiological and sensory mechanisms are likely involved in such modulation.In the last part of the Thesis work, we investigate the putative influence of aroma perceptionon chlorine flavour. Our results showed that beyond chemical reactions between hypochlorous acid and odorants, aromas at peri-threshold concentration enhance chlorine flavour and decrease tap water acceptability
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Gu, Zhimang. "Development and evaluation of innovative iron-containing porous carbon adsorbents for arsenic removal." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/5864.
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Thesis (Ph. D.)--University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 10, 2007) Vita. Includes bibliographical references.
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Holland, Valerie Ann. "Evaluation of conventional treatment processes for removal of nitrosodimethylamine (NDMA) from drinking water /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1426067.
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Omur-Ozbek, Pinar. "Macromolecular Reactions and Sensory Perception at the Air-Water-Human Interface." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/77226.
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During 20th century main concern was to have sanitary water flowing through the tap. In 21st century constant supply of safe drinking water is common at any home in USA. Hence consumers pay attention to aesthetic quality of tap water. Odorous algal metabolites in source water and metals introduced to drinking water due to corrosion of pipes in the distribution system cause taste, odor and color problems, and result in complaints and perception of tap water as unhealthy. Millions of dollars are spent each year by water industry to address and prevent these issues.
This research focused on some of the taste-and-odor issues associated with drinking water. First aim was to understand when geosmin, 2-MIB, and nonadienal become detectable, employing two-resistance mass transfer theory to determine the concentration of odorants in bathroom air. Results showed that water temperature and odorant concentration in water play an important role. Next focus was to develop an international odor standard to be used for training of sensory analysis panelists. There are many sensory methods to monitor drinking water to detect the off-flavors however an odor standard has been missing. Hexanal was studied with trained flavor profile analysis panels and was proposed as an ideal odor reference standard to be used for training and sensory assessment of water samples. Main focus was to understand metallic flavor of drinking water caused by iron and copper. It was shown that metallic sensation has taste and retronasal components creating the flavor and humans are very sensitive to it. Occurrence of lipid oxidation in the oral cavity was shown when metals were ingested, that produces carbonyls which are responsible for the metallic flavor. Antioxidants and chelators were investigated to study prevention of lipid oxidation and, chelators were determined to be more effective. Oral epithelial cell cultures were developed as a model for oral cavity to further investigate lipid oxidation and effectiveness of the antioxidants and chelators.
This dissertation is a result of inter-disciplinary work and possibly a good example for how problems may be solved by incorporating different methods and point of views from several disciplines.Ph. D.
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Mirlohi, Susan. "Characterization of Metallic Flavor in Drinking Water: An Interdisciplinary Exploration through Sensory Science, Medicine, Health, and the Environment." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77313.
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Scientific explorations can lead to life changing discoveries or light the path for new discoveries as scientists continue to carry or pass on the torch of knowledge to current and future generations. This torch of knowledge radiates in many directions, as the path of discovery often demands a multidimensional perspective. This research explored the many aspects of metallic flavor in drinking water through applications of sensory science, medicine, health, and the environment.
Humans interact with their environment through the five senses and are often exposed to contaminants through multiple routes; oral intake of trace metal contaminants through drinking water is a likely source. The biochemical mechanism by which humans are able to detect the flavor of strongly metallic agents such as iron has been previously elucidated, but little is known about population variability in the ability to sense metallic flavors. This research evaluated sensory thresholds and biochemical indicators of metallic flavor perception in healthy adults for ferrous iron in drinking water; 61 subjects aged 19 – 84 years, participated. The findings demonstrated an age-dependent sensitivity to iron indicating as people age they are less sensitive to metallic perception; impairment of olfactory functions is a contributing factor.
Unlike in healthy adults, where human senses are often protective of overexposure to contaminants, and supportive of sensations of everyday life's pleasures, cancer patients often suffer from chemosensory dysfunctions. Metallic phantom taste is a commonly experienced sensation, yet very little studied aspect of this debilitating disorder. Impact of cancer therapy on chemosensory functions of patients with malignant brain tumors undergoing combined modality treatment (CMT) was explored. The results indicated that chemosensory dysfunctions of the patients can range from minimal to moderate impairment with maximum impairment developing during the 6-week CMT. Study of salivary constituents may provide clues on to the causes of chemosensory dysfunctions.
On health aspects, implication of individual sensitivity to metallic flavor on beverage choices and overall water consumption was assessed in 33 healthy adults through self-reported beverage questionnaire. The results indicated that among the elderly reduced intake of drinking water coincided with reduced sensitivity to metallic flavor. The findings have important health implications in terms of hydration status and beverage choices.
Finally, with environmental exposure relevance, preliminary findings on sensory properties of zerovalent iron nanoparticles (nZVI) indicated that oral exposure to nZVI may induce sensory properties different from that of ferrous iron, likely predictive of a diminished detection of metallic flavor by humans. Further research is warranted in this area.Ph. D.
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Gregg, Anne M. "Arsenic in drinking water: the public health implications of monitoring technologies." The Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=osu1195673218.
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Miller, Candace D. "Evaluation of the Compartment Bag Test for the Detection of Escherichia coli in Drinking Water." Digital Archive @ GSU, 2013. http://digitalarchive.gsu.edu/iph_theses/264.
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INTRODUCTION: More than 1.8 million diarrheal disease deaths can be attributed to the lack of access to water, sanitation and hygiene. These deaths occur mostly in developing countries where water quality testing resources are limited. Several tests are currently used to detect and quantify E. coli and other fecal coliforms in drinking water, however they can be expensive, complex, and technically demanding. There is a need for a simple, reliable, low-cost water quality test that can be used in resource limited settings. Therefore, the purpose of this research was to perform a rigorous evaluation of the recently developed compartment bag test for detection and quantification of E. coli against the standard method, membrane filtration.
METHODS AND RESULTS: A total of 270 water samples were collected from forty-five various naturally contaminated water sources around metro-Atlanta from August 2011 through April 2012 and processed using the compartment bag test and membrane filtration with mI agar. Concentrations of E. coli were significantly correlated with a correlation coefficient of 0.904 (95% CI 0.859 – 0.950). Sensitivity and specificity were 94.9% and 96.6%, respectively.
CONCLUSION: These results suggest that the compartment bag test produces results consistent with those produced by membrane filtration on mI agar. Based upon its performance, the compartment bag test has the potential to be used as a reliable, low-cost drinking water quality test globally where water quality testing resources are not readily available, and can be implemented in monitoring activities for microbial water quality.
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Greyshock, Aimee E. "Evaluation of Triclosan Reactivity in Monochloraminated Waters." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/36295.
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The antibacterial agent, triclosan, is widely used in many household personal care products, and it has recently been detected in wastewater treatment plant effluents and in source waters used for drinking water supply. Accordingly, the reactivity of triclosan with the disinfectants used in wastewater treatment and in the production of potable water is of interest. Monochloramine is used as an alternative disinfectant in drinking water treatment to minimize production of regulated disinfection by-products. This study examined the reactions between triclosan and monochloramine and involved analysis of monochloramine and triclosan decay and product formation under drinking water treatment conditions over a pH range of 6.5 to 10.5. Monochloramine decay in the presence of triclosan was measured relative to monochloramine auto-decomposition in the absence of triclosan using UV-VIS spectrophotometry. Experimental results showed that the monochloramine auto-decomposition intermediates, free chlorine and dichloramine, are responsible for a majority of the observed triclosan decay and product formation. A kinetic model for monochloramine auto-decomposition was modified to include terms and rate coefficients for the reactions of triclosan with monochloramine (k = 90.4 M-1h-1), free chlorine (k = 1.94×107 M-1h-1), and dichloramine (k = 2×105 M-1h-1), and was able to predict triclosan and monochloramine decay. It was determined that the reactions of dichloramine and free chlorine with triclosan were 103 and 105 times faster, respectively, than the reaction of monochloramine with triclosan. The products of these reactions, detected using GC-MS, included three chlorinated triclosan intermediates, 2,4-dichlorophenol, and 2,4,6-trichlorophenol. Low levels of chloroform were detected at pH values of 6.5 and 7.5.Master of Science
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Coulbert, Brittany 1981. "An evaluation of household drinking water treatment systems in Peru : the table filter and the safe water system." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/28928.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2005.Includes bibliographical references (p. 257-261).
(cont.) storage, and education. Tests on the SWSs in Peru demonstrated 99.6% E.coli removal and 95% total coliform removal. Only 30% of the SWSs tested contained water at or above the WHO-recommended concentration of free chlorine residual (0.2 mg/L). The author recommends that use of these HWTSs continues and that the program receives increased support. The two HWTSs would be most effective if combined: filtration plus post-chlorination. In order to further distribute these systems in the future, a sustainable funding plan must be created.
A household water treatment program was implemented in southern Peru in 2003 by CEPIS and the country's Ministry of Health. This program involves the use of two household water treatment systems (HWTSs): the Table Filter and the Safe Water System. The author and a team of researchers from MIT traveled to Peru in January 2004 to assess the program and technologies through water quality tests and personal interviews. This research continued in Peru during March 2004 by local chemical engineering graduates of San Augustine National University. The Table Filter is a combination filter, involving a geotextile cloth pre-filter, sand, and two Pozzani ceramic candles from Brazil. Table Filters tested in Peru provided an average 99% E.coli removal, 98% total coliform removal, and 67% turbidity removal. Two Table Filters were also tested at MIT, using two different grades of sand. The "Medium Sand Table Filter" demonstrated 98% thermotolerant coliform removal and 91% turbidity removal, and the "Fine Sand Table Filter" showed 98% thermotolerant coliform removal and 92% turbidity removal. Tests performed on the Pozzani ceramic candles alone (without sand) showed similar coliform removal rates and slightly decreased turbidity removal rates, although the difference was statistically insignificant. Previous research shows that this combination of filtration media helps sustain a higher flow rate through the filters (Rojas & Guevara, 2000). Thus the chief advantage of the complete Table Filters, over the Pozzani ceramics candles alone, is a sustained higher flow rate, not coliform or turbidity removal. The Safe Water System (SWS), designed by the Centers for Disease Control and Prevention, involves local small-scale chlorine generation, household
by Brittany Coulbert.
M.Eng.
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Ikegami, Takao. "Problems of municipal drinking water supply and evaluation of a chlorinated by-products policy." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/74774.
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Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH.
Bibliography: leaves 75-84.
by Takao Ikegami.
M.C.P.
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Shane, William T. "Persistence of Spore Forming Bacteria on Drinking Water Biofilm and Evaluation of Decontamination Methods." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1205164893.
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Graybeal, Dale Kevin. "Evaluation of water distribution system monitoring using a combined simulation-optimization approach." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-01312009-063527/.
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Krentz, Corinne Andrea. "An evaluation of new and traditional approaches to monitor drinking water quality in British Columbia." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43369.
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Microbiological monitoring of drinking water is a critical element in the source-to-tap framework. This research provides an assessment of traditional and alternative approaches to drinking water monitoring, explores new applications for existing indicators and evaluates a new tool to manage fecal contamination in water.
British Columbia (BC) Drinking Water Protection Regulation requires that drinking water samples be tested at an accredited laboratory. This creates challenges related to accessibility for some systems. The objective was to evaluate the agreement between indicator bacteria test results obtained with the current approach and an alternative approach using a presence/absence test close to the point of sample collection. Samples were collected from 83 small systems in the South Cariboo, BC. The agreement measured using Cohen’s kappa was moderate to substantial for total coliforms (0.64 ± 0.11) and E. coli (0.73 ± 0.20).
The value of monitoring total coliforms and E. coli in parallel is a topic of current debate. The objective was to evaluate the potential for non-E. coli total coliform events to predict E. coli occurrence in subsequent drinking water samples. Life table analysis of microbiological testing data from small systems in BC showed that systems with a positive non-E. coli total coliform result were twice as likely to observe an E. coli-positive result in a subsequent water sample compared to systems that had not tested positive for total coliforms previously (RR=2.04).
Routine drinking water samples containing indicator bacteria are not analyzed further to investigate sources of fecal contamination. The objective was to develop a tool to identify fecal contamination sources in BC drinking water and evaluate the tool using water samples with evidence of fecal contamination. Markers associated with human, livestock and wildlife contamination were selected. Singleplex and multiplex polymerase chain reaction (PCR) was used to test contaminated raw water and drinking water samples for presence of host-associated markers. Low sensitivity of the multiplexed reaction limits its use to detect levels of markers present in contaminated drinking water samples. Singleplex PCR using host-associated markers is a promising tool to identify fecal contamination sources in small volumes of raw and drinking water.
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Rust, Annette. "Development and evaluation of a PCR protocol to detect Escherichia coli in drinking water samples /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17499.
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Lindkvist, Jonas. "Social, Economical and Technical Evaluation of a reverse osmosis drinking water plant in the Stockholm Archipelago." Thesis, KTH, Industriell ekologi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32777.
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The drinking water plant in this case study is a combined groundwater and reverse osmosisplant in the Stockholm archipelago. The reverse osmosis purification step was added to theplant in 1995. This technique is relatively new in Sweden and there are possibilities for it tobecome a good complement to conventional drinking water treatment. The plant has used thistechnique for over 10 years with good results. It is therefore of great interest to evaluate anddocument it for the possibility to implement this technique in areas not connected toconventional drinking water production.Reverse osmosis separates the incoming water to a clean permeate and concentrate ofremoved particles, larger molecules and ions. This technique has a high purification degree. Itcan remove dissolved particles and microorganisms without disinfection. However, it isrelatively expensive due to a high electricity consumption compared to conventional drinkingwater treatment. The high electricity consumption in this kind of system depends on aphenomenon called membrane fouling caused by the constituents in the raw water, graduallybecoming enriched on the membrane surface.The aim of this thesis was to evaluate and document a drinking water plant in the Stockholmarchipelago from a social, economical, technical and environmental perspective. A socialsurvey in the form of a questionnaire was conducted to reveal opinions about the water qualityprovided by the plant. The economical evaluation was done to estimate the cost of drinkingwater production and find the water cost in Kr/m3. The technical part involved documentationof the plant layout and evaluation of its performance. To assess the performance historicalchemical and microbial analyses were evaluated. A mass balance was attempted to drawconclusions for the overall system. The environmental part of the plant assessment, includedan estimate of the electricity and chemicals use in the plant.The results revealed that from an overall perspective the water quality from the plant issatisfactory with some concerns about metal taste and turbidity that sometimes occur. Thepotential presence of dangerous algal toxins in the water was also a concern. The totalproduction cost in Kr/m3 is higher than expected and higher than sales price. In technicalterms, the plant has functioned well. However, there is a need to monitor more parameters inthe plant including; more flow parameters, concentrations of added chemicals and more waterquality parameters. Electricity consumption has been higher than expected. Control(throttling) valves in the brine reject are relatively large energy consumers and arecommendation is to investigate potential savings by changing them for pressure exchangevalves.www.ima.kth.se
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Rathor, Ankur. "Web-based Performance Benchmarking Data Collection and Preliminary Analysis for Drinking Water and Wastewater Utility." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/49582.
Full textAbstract:
High-quality drinking water and wastewater systems are essential to public health, business, and quality of life in the United States. Even though the current performance of these systems is moderate, the concern is about the future performance. Planning can be done for improvement once the current performance of utilities is evaluated, and areas with a scope of improvement are identified. Benchmarking and performance evaluation are key components in the process of continuous improvement for utility\'s performance. Benchmarking helps utilities make policies and programmatic decisions that reduce operational expenses and increase productivity by understanding areas of underperformance, understanding customer needs, developing future plans, and setting goals. This study establishes a strong case for implementing benchmarking methodologies among utilities to evaluate and improve performance. There are many initiatives on performance benchmarking of utilities but a few of them focuses on one or few area of performance. There are a few initiatives which use subjective indicators. Additionally, consultants visit the utilities for performance evaluation. This research focuses on creating a web-based benchmarking platform for performance evaluation using holistic and quantitative indicators. Practical and robust methodologies are used and the research presents the current performance comparisons among utilities for areas that impact overall utility\'s performance. Web based benchmarking consists of two major parts -- data collection and result visualization. A major contribution from this study is the creation of an online performance benchmarking database. With time more data will be collected which will provide utilities an access to a better database for performance evaluation. The future work in this research will be analyzing the data and results for each participant for each set of indicators, and finding possible reasons for under performance, followed by suggesting solutions for improvement using the best practices.
Master of Science
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Tellez, Sanchez Sarita Lucia. "Household Water Filter Use Characterization in Rural Rwanda: Signal Interpretation, Development and Validation." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/3026.
Full textAbstract:
Access to safe drinking water is an important health factor in many developing countries. Studies have shown that unsafe drinking water and poor sanitation practices leads to diarrheal disease, which is one of the leading causes of death of children under five in developing countries. Provision and proper use of household water filters have been shown to effectively improve health.
This thesis is focused on the refinement and validation of algorithms for data collected from pressure transducer sensors that are used in household water filters (the Vestergaard Frandsen LifeStraw Family 2.0) deployed in Rwanda by the social enterprise DelAgua Health. Statistical and signal processing techniques were used to detect the use of the LifeStraw water filters and to estimate the amount of water filtered at the time of usage. An algorithm developed by Dr. Carson Wick at Georgia Institute of Technology was the baseline for the analysis of the data. The algorithm was then refined based on data collected in the SweetLab at Portland State University, which was then applied to field data.
Laboratory results indicated that the mean error of the improved algorithm is 11.5% as compared with the baseline algorithm mean error of 39%. The validation of the algorithm with field data yielded a mean error of 5%. Errors may be attributed to real-world behavior of the water filter, electronic noise, ambient temperature, and variations in the approximation made to the field data. This work also presents some consideration of the algorithm applied to soft-sided water backpacks.
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Pincus, Melanie I. (Melanie Ita) 1980. "Safe household drinking water via BioSand filtration pilot project evaluation and feasibility of a BioSand pitcher filter." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/85735.
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Gibson, Jonathan. "Economic evaluation of health risks in a developing country : the case of arsenic contaminated drinking water in Cambodia." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/economic-evaluation-of-health-risks-in-a-developing-country-the-case-of-arsenic-contaminated-drinking-water-in-cambodia(d934a610-d90f-4989-99f3-4937e1076742).html.
Full textAbstract:
Arsenic contamination of drinking water is a serious public health issue in many areas of South and South East Asia. One study estimates that in Cambodia over 100,000 people are exposed, with the majority of those living in Kandal Province. In this thesis we present 3 original empirical studies focused on estimating nonmarket values for reduced arsenic risk water, based on primary data collected in May 2013. We also present a review paper which discusses the various economic techniques which have typically been used to estimate welfare values for cost-benefit analysis of mitigation strategies or appraisal of drinking water standards. The first empirical paper presents the results of a discrete choice experiment (DCE)to estimate willingness to pay (WTP) values for reduced arsenic water. We discuss the results of scale-extended latent class choice models and underlying differences in preferences and choice consistency. We find that a reduction in the permissible limit on arsenic in drinking water may best represent underlying household preferences for risk. The second empirical paper presents the results of a split sample choice experiment focusing on differences between money (WTP) and labour contributions (WTWork) as payment vehicles in terms of choice behaviour and attribute non-attendance. We find that the results from the two experiments are relatively consistent which reinforces our results from the previous chapter that focuses on WTP measures alone and adds credibility to the large numbers of DCEs conducted in rural areas of developing countries. The final empirical paper examines actual household behaviour relative to an arsenic testing and education campaign run by a local NGO. We find that the vast majority of households change their drinking water source upon being informed that it is unsafe. On average households that switch increase their expenditures. In doing so however they also reduce the amount of time spent collecting water which limits the use of expenditure changes as an approximation of welfare values.
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Dodd, Jennifer Peters. "Chemical Identification and Organoleptic Evaluation of Iodine and Iodinated Disinfection By-Products Associated with Treated Spacecraft Drinking Water." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36642.
Full textAbstract:
Aboard the International Space Station, potable water will likely be produced from recycled wastewater. The National Aeronautic and Space Administration (NASA) plans to use iodine as a disinfectant, and, consequently, the formation of iodinated disinfection by-products (IDBPs) requires investigation. Objectives of this research were to determine possible precursors of IDBPs, identify IDBPs formed, and apply flavor profile analysis (FPA) as a tool to evaluate water qaulity. Experiments were performed by separately reacting iodine with each of the following organic compounds: methanol, ethanol, 1-propanol, 2-propanol, 1-methoxy-2-propanol, acetone, and formaldehyde. NASA previously identified all of these compounds in wastewater sources under consideration for recycling into potable water. Experiments were performed at pH 5.5 and 8, iodine concentrations of 10 and 50 mg/L, and organic concentrations of 5 and 50 mg/L. Gas chromatography/mass spectrometry was used to identify and monitor the concentrations of organic species. Spectrophotometry was used to monitor the iodine concentration. Acetone was the only compound identified as an IDBP precursor and it reacted to produce iodoacetone and iodoform. Concentrations of iodoform from 0.34 mg/L to 8.637 mg/L were produced at conditions that included each pH level, iodine concentration, and acetone concentration. The greatest iodoform concentration was produced at pH 8 from 50 mg/L of iodine and acetone. FPA indicated that the odor threshold concentration (OTC) of iodoform was 1.5 ug/L, and the OTC of iodine was 500 ug/L. Both iodine and iodoform have medicinal odors, making it difficult to distinguish each compound when present in a mixture.Master of Science
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Hosni, Ahmed A. "Evaluation of Chlorine Dioxide as a Possible Disinfectant in Drinking Water Networks in Case of a Bioterrorism Attack." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1241012642.
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St, Clair Alison Marie. "Development of a Novel Performance Index and a Performance Prediction Model for Metallic Drinking Water Pipelines." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/19342.
Full textAbstract:
Previous authors have developed many different types of water pipe condition and failure models using the various methodologies available. Contrary, current utilities are struggling to maintain their current water infrastructure system, due to the lack of effective prediction tools at hand. The gap between the methodologies available in academic research and the tools available to current water utilities needs to be addressed. This paper presents a fuzzy inference prediction model used to forecast the performance rating of individual drinking water pipeline sections (node to node) in which utilities can easily apply to their drinking water infrastructure system.Prior to the development of a prediction model, a through literature and current practice review is completed detailing and summarizing all the available mathematical models. Following, an infrastructure overview is presented detailing the various pipe materials, lifecycle and failure modes and mechanisms. A data structure is also detailed which lists all parameters that affect the condition and/or performance of a pipeline. All of these tools are successfully used to develop a fuzzy inference performance model.
The fuzzy inference performance model is considered novel in that it considers close to 30 pipe parameters. Moreover, the performance model is applied using the Western Virginia Water Authority (WVWA) and the Washington Suburban Sanitary Commission (WSSC) databases to evaluate and verify the predicting results. Lab testing of several pipe samples is also used to evaluate the model. The testing consists of a ring bearing test which is used to calculate the rupture modulus of the pipe. Comparing the original vs. the current rupture modulus can determine the remaining strength of the pipe. The remaining strength can then be used to assess the performance results predicted by the fuzzy inference model.
Further a framework is set forth which utilizes the model\'s predicted performance ratings to develop deterioration curves which can be used as a tool to forecast and plan future inspection, repair, rehabilitation and replacement of water pipelines. The deterioration model is made up of a Markov chain approach coupled with a non-optimization technique.
Ph. D.
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Van, der Merwe Liesl. "The qualitative and quantitative evaluation of estrogen and estrogen-mimicking substances in the South African water environment / Liesl van der Merwe." Thesis, Potchefstroom University for Christian Higher Education, 1998. http://hdl.handle.net/10394/1342.
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Recently some chemicals has been accused of mimicking the female hormone
estrogen. The mode of action is termed estrogen-mimicking, because of the effects
that is produced by these chemicals. Playing canary in a coal mine, wildlife was the
first to indicate that something was wrong. Reproductive abnormalities such as
abnormal sperm, reduced sperm production, cryptorchidism (undescended testes).
abnormal hormone levels – particularly high estrogen ratios to that of testosterone.
infertility, and genital abnormalities were all evidence that something in the
environment was affecting the reproductive status of these animals. Also in humans
instances like rising cases of infertility, abnormal sperm conditions and cases of
breast cancer raised an increased concern about the potential disruptive effects of
these substances on the human existence. After investigations were conducted, it
was found that substances which enhance the quality of life like some detergents,
agricultural products, additives to plastic, dyestuffs, paint components and
pharmaceuticals to name but a few, all caused an abnormal reproductive status as
seen in animals. The aims of this study were not to focus on the effect of these
substances, but rather to identify estrogen and estrogen - mimics in the South
African environment and to evaluate their presence in the water environment
qualitatively and quantitatively with the most suitable analytical methods. Estrogen -
mimics such as nonylphenol. o'p' and p'p' DDE, o'p' DDD, lindane, atrazine and the
PCB's : Arochlor 1254 & Arochlor 1260 were found to contaminate the environment.
The drinking water tested of the PWV area indicated that the water was free of these
substances, and thus indicated a present safe situation.Thesis (MSc (Farmaseutika))--PU for CHE, 1998
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Salley, Dara C. "Evaluation of an on-line extraction, real-time detection sampler and application to environmental sampling of Syracuse, NY drinking water for atrazine." Thesis, State University of New York Col. of Environmental Science & Forestry, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1568948.
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MONITOR is an active, automatic extraction sampler that collects daily, integrated extracts of hydrophobic compounds in water. Compounds partition from water, through a polydimethylsiloxane membrane and into hexane. The sampling rate, membrane-water partition coefficients (KMW) and hexane-water partition coefficients (KHW) were determined for atrazine and four nonpolar reference compounds. The reference compounds had high effective sampling rates (>10 L/day) while atrazine had a low effective sampling rate (<1 L/day). Atrazine had intermediate hydrophobicity as determined by KMW and octanol-water partition coefficient (KOW). However, atrazine had a low KHW, which caused its low sampling rate. In spite of MONITOR's low sampling rate for atrazine, the concentration of atrazine in the drinking water of Syracuse, New York was observed from March - November 2012 using MONITOR. The average concentration was 0.016 μg/L. MONITOR was able to capture fluctuations in the concentration of atrazine at very low levels over several months.
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White, Colin P. "Molecular Microbial Ecology and Operational Evaluation of a Full-scale and Pilot-scale Biologically Active Filter for Drinking Water Treatment." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1277154047.
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MOHD, REDZUAN BIN RAMLI. "EVALUATION OF PERFLUOROALKYL ACIDS (PFAAs) IN WATER ENVIRONMENT, FOOD, AND HUMAN BODY IN KLANG VALLEY, MALAYSIA." Kyoto University, 2019. http://hdl.handle.net/2433/244539.
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Lindegren, Klara. "Evaluation of the Removal Efficiency of Per- and Polyfluoroalkyl Substances in Drinking Water using Nanofiltration Membranes, Active Carbon and Anion Exchange." Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-268448.
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Per- and polyfluoroalkyl substances (PFASs) is a group of man-made, highly persistent chemicals. Due to the specific surface-active attributes of these molecules, applications are numerous and feed an economically important industry. During the last decade, PFASs have been detected globally in the environment, living organisms and tap water. The combination of toxic properties and high bioaccumulative potential, together with the discovery that conventional water treatment methods do not remove PFAS, renders further research on purification methods highly needed. Three techniques of purifying water from PFASs were examined. Nanofiltration technology (NF) is a membrane filtration technique, which produces a purified product (the permeate) by generating an effluent of high contaminant concentration (the reject water). To decontaminate the reject water, adsorption by granular activated carbon (GAC) or anion exchange (AE) have been proposed. The efficiency of these three technologies was studied at Bäcklösa drinking water treatment plant (DWTP) in Uppsala. A nanofiltration pilot with two 270NF membranes (Dow Filmtech™), connected in series, was used. A high removal efficiency (>90%) was found for all PFASs. Furthermore, it was confirmed that the concentration in the permeate water was a function of the concentration in the incoming raw water; increased PFAS raw water concentration resulted in increased PFAS permeate concentration. Size-exclusion and electrostatic repulsion were deemed important mechanisms. For the comparison of GAC (Filtrasorb 400®) and AE (Purolite® A-600), a column experiment was set up. The perfluoroalkane (-alkyl) sulfonic acids (PFSAs) and perfluorooctanesulfonamide (FOSA) had similar removal efficiencies using both GAC and AE, and the efficiency increased with increasing chain length. AE was found to have a higher average removal efficiency of perfluoroalkyl carboxylic acid (PFCAs) (62-95%) than GAC (49-81%). In conclusion, longer chain length PFASs were removed more effectively than shorter-chained, and the PFSAs and FOSA showed higher removal efficiency compared to the PFCAs. Furthermore, linear isomers were removed more effectively than branched for GAC and AE. In contrast, the opposite was found for the NF membrane, where branched isomers were better retained.Per- och polyfluorerade alkylsubstanser (PFAS) är en grupp syntetiska, ytterst persistenta kemikalier. På grund av deras ytaktiva egenskaper är de lämpliga för användning i många produkter och tillverkningsprocesser, och är således viktiga för en ekonomiskt betydande industri. Under det senaste årtiondet har PFAS påträffats i miljön, levande organismer och kranvatten världen över. Kombinationen av toxiska egenskaper, en hög bioackumuleringspotential och upptäckten att konventionella reningsmetoder inte avlägsnar substanserna från vatten, gör att vidare forskning av reningsmetoder för PFAS är mycket angelägen. Tre reningsteknikers förmåga att rena vatten från PFAS undersöktes. Nanofiltrering (NF) är en membranfiltreringsteknik som utöver den renade produkten, permeatet, även framställer en biprodukt av hög föroreningsgrad, rententatet. För att rena rententatet har adsorption till granulärt aktivt kol (GAC) eller jonbytarmassa (AE) föreslagits. Teknikerna utvärderades på Bäcklösa Vattenverk i Uppsala. Nanofiltreringen undersöktes i en pilotanläggning där två 270NF (Dow Filmtech™) membran var seriekopplade. En hög reningsgrad (>90%) konstaterades för alla typer av PFAS. Vidare visades PFAS-koncentrationen i permeatet vara en funktion av PFAS-koncentrationen i råvattnet; en ökad råvattenkoncentration gav en ökad permeatkoncentration. Storleksseparation och elektrostatisk repulsion befanns vara viktiga mekanismer som påverkade reningsgraden. För att undersöka de mekanismer som påverkar PFAS-adsorption jämfördes GAC (Filtrasorb 400®) och AE (Purolite® A-600) i ett kolonnexperiment. Reningsgraden för GAC och AE av perfluorerade sulfonsyror (PFSA) och perfluorooktan sulfonamider (FOSA) var lika hög och reningseffektiviteten ökade med ökande kolkedjelängd. AE återfanns ha en högre genomsnittlig reningsgrad av perfluorkarboxylsyror (PFCA) (62-95%) än GAC (49-81%). Sammanfattningsvis avlägsnades PFAS av längre kolkedjelängd mer effektivt än kortare kolkedjor, och PFAS med sulfonsyror och sulfonamider som funktionella grupper uppvisade en högre reningsgrad än karboxylsyrorna. Vidare renades linjära isomerer mer effektivt än grenade både genom GAC och AE. Däremot konstaterades det motsatta för NF-membranen, där grenade isomerer renades mer effektivt.
SafeDrink
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Galicia, Oswaldo. "Development and Application of Decision-Making Tool for Rural Spring-Sourced Gravity-Fed Community Managed Water Systems." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7790.
Full textAbstract:
People all over the world still lack access to safe drinking water service. Those with access experience several issues during the first few years of installation that impede on their overall access. In order to improve water services, not only is a proper decision-making tool necessary, taking into account key factors that impact sustainable water service, but proper monitoring and evaluation is also important in ensuring service for the long term. There are several developed assessment tools used for monitoring and evaluation of water systems post-construction, applicable in various scenarios. However, there are only few tools available to facilitate the decision-making process for stakeholders implementing water systems in the field. Ideally, one tool could be used across various life-cycle stages, like planning (decision-making) and post-construction (monitoring and evaluation).
Currently, several stakeholder groups are working in Panama to improve the access of safe drinking water for rural and indigenous populations living in mountainous areas, where spring-sourced gravity-fed community-managed systems are common. Effective sustainability assessment tools including Rural Water and Sanitation Information System, SIASAR in Spanish, provide useful frameworks to create a decision making tool for this development context.
This research focused on developing a Decision-Making Tool using three key assessment tools (SIASAR, Peace Corps Panama WASH Index, & Schweitzer’s Sustainability Assessment Tool), field experience, and relevant literature incorporating technical, social, economic, and environmental factors. The Decision-Making Tool was developed to build or rehabilitate a rural spring-sourced gravity-fed community-managed water system and also serve as a practical monitoring and evaluation tool. The tool has a total of 10 indicators and 20 measures used to score various scenarios or alternatives as sustainability unlikely, sustainability possible, or sustainability likely.
The tool was successfully applied as a monitoring and evaluation (M&E) tool for the rural indigenous community of Quebrada Cacao in the province of Bocas del Toro in Panama. A total of 5 alternatives scenarios with estimated costs, labor expenditure and environmental impact were developed using EPANET and SimaPro to help improve the community’s rural spring-sourced gravity-fed community managed water system. Using analytical hierarchy process with weights set by three stakeholder groups in Panama (Quebrada Cacao’s water committee, Panama’s Ministry of Health, and Peace Corps Panama), these five alternative scenarios were scored using the Decision-Making Tool.
As a result, a feasible alternative was recommended for the community of Quebrada Cacao using the developed Decision-Making Tool. The tool was also successfully applied as a monitoring and evaluation tool, providing a baseline to develop applicable alternatives to improve the community’s sustainability score. This Decision-Making Tool fulfills an important gap useful for both planning and monitoring and evaluation. It provides a successful tool for application in Panama for building or rehabilitating rural spring-sourced gravity-fed community managed water systems and for other countries with a similar context. Finally, the tool also considers technical, economic, social, and environmental factors, ensuring a more holistic definition of sustainability when building or rehabilitating these water systems. Overall, this Decision-Making Tool can help reduce the number of people without access to safe drinking water around the world and also help ensure systems function sustainably for the long term.
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Westgate, Amy. "Evaluation of novel polyethersulfone membranes incorporating charged surface modifying macromolecules for the removal of pharmaceuticals and endocrine disrupting compounds from drinking water." Thesis, University of Ottawa (Canada), 2008. http://hdl.handle.net/10393/27743.
Full textAbstract:
Recently, there has been an increased concern of the potential effects of pharmaceuticals, personal care products (PPCPs) and endocrine disrupting compounds (EDCs) in drinking water. Their presence in surface waters has resulted in the skewing of sex ratios in aquatic biota and the effect on humans, as yet, remains unknown. Investigation into the effective removal of these compounds by water treatment plants (WTPs) has shown that conventional treatment processes are not very effective in removing these trace compounds. Studies have shown PPCPs and EDCs have been successfully removed by commercial nanofiltration (NF) and reverse osmosis (RO) membranes, but have low flux and high cost. North American WTPs, using membrane separation processes, are typically equipped with microfiltration (MF) or loose ultrafiltration (UF) membranes which, thus far, have proven ineffective for the removal of these target compounds.
This thesis focuses on the development of a tight charged UF membrane that effectively removes PPCPs and EDCs from drinking water while still maintaining a high flux and is cost effective. Novel membranes were developed by incorporating charged surface modifying macromolecules (CSMMs) in the manufacturing of polyether sulfone (PES) based membranes. The charged additives were expected to enhance the removal of PPCPs and EDCs by charge repulsion. Controls and three different CSMM (DEG-HBS, DEG-HBC and PPG-HBC) blended membranes were prepared at three different casting conditions and subsequently evaluated for various properties: flux, molecular weight cut-off (MWCO), porosity, charge and contact angle. Experimental membranes were further evaluated for the removal of four representative target compounds, sulfamethazine (SMZ), carbamazepine (Carb), bisphenol A (BPA) and ibuprofen (IB). Removal by a commercial nanofiltration membrane, NF270 (DOW/FilmTec) was compared to the experimental membranes.
Removal results from the experimental membranes indicate membranes were unable to sustain effective removal of the target compounds. Typically, removal was initially high but decreased over the run. Membrane characteristics showed membranes had significantly larger pores than the target compounds indicating size exclusion was not the removal mechanism. Charge results indicated CSMM blended membranes were generally unchanged from the control membrane indicating, in addition to the unsustained removal, that charge repulsion was not the removal mechanism. From the shape of the removal curves, it is assumed the removal mechanism is the result of membrane adsorption.
The CSMMs were found to have modified the membranes, though not sufficiently, to be considered significantly different than the controls in many respects. Membrane characteristics varied as a result of each CSMM incorporated and depending on each casting condition. Contact angle results for both PES-DEG-HBS and PES-PPG-HBC membranes at all three casting conditions increased in comparison to the controls, presumably because of changes in surface roughness. PES-DEG-HBC, on the other hand, decreased in contact angle at 18%, and increased in contact angle at 20% in comparison to the respective controls. Incorporation of migration time, particularly in the case of DEG-HBC, increased membrane flux without affecting MWCO. Increased PES concentration (from 18 to 20%) saw an increased target compound removal. With the success of the DEG-HBC CSMM, incorporation of migration time at higher PES concentrations appears promising for achieving the desired characteristics. It is recommended that further optimization using CSMM DEG-HBC at increased PES concentrations with migration time be investigated for this application.
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Marshall, Katherine C. "An Evaluation of the Water Lifting Limit of a Manually Operated Suction Pump: Model Estimation and Laboratory Assessment." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/7056.
Full textAbstract:
With 663 million people still without access to an improved drinking water source, there is no room for complacency in the pursuit of Sustainable Development Goal (SDG) Target 6.1: “universal and equitable access to safe and affordable drinking water for all” by 2030 (WHO, 2017). All of the current efforts related to water supply service delivery will require continued enthusiasm in diligent implementation and thoughtful evaluation. This cannot be over-emphasized in relation to rural inhabitants of low-income countries (LICs), as they represent the largest percentage of those still reliant on unimproved drinking water sources. In that lies the motivation and value of this thesis research- improving water supply service delivery in LICs.
Manually operated suction pumps, being relatively robust, low cost, and feasible to manufacture locally, are an important technology in providing access to improved drinking water sources in LICs, especially in the context of Self-supply. It seems widely accepted that the water-lifting limit of suction pumps as reported in practice is approximately seven meters. However, some observations by our research group of manually operated suction pumps lifting water upwards of nine meters brought this “general rule of thumb” limit into question. Therefore, a focused investigation on the capabilities of a manually operated suction pump (a Pitcher Pump) was conducted in an attempt to address these discrepancies, and in so doing, contribute to the understanding of this technology with the intent of providing results with practical relevance to its potential; that is, provide evidence that can inform the use of these pumps for water supply.
In this research, a simple model based on commonly used engineering approaches employing empirical equations to describe head loss in a pump system was used to estimate the suction lift limit under presumed system parameters. Fundamentally based on the energy equation applied to incompressible flow in pipes, the empirically derived Darcy-Weisbach equation and Hydraulic Institute Standards acceleration head equation were used to estimate frictional and acceleration head losses. Considering the theoretical maximum suction lift is limited to the height of a column of water that would be supported by atmospheric pressure, reduced only by the vapor pressure of water, subtracting from this the model was used to predict the suction lift limit, also referred to herein as the practical theoretical limit, assuming a low (4 L/min) and high (11 L/min) flow rate for three systems: 1) one using 1.25-inch internal diameter GI pipes, 2) one using 1.25-inch internal diameter PVC pipes, and 3) one using 2-inch internal diameter PVC pipes. In all considered cases, with an elevation equal to sea level, the suction lift limit was estimated to be over nine meters. At a minimum, the suction lift limit was estimated to be approximately 9.4 meters for systems using 1.25-inch internal diameter pipe and 9.8 meters for systems using 2-inch internal diameter pipe, with essentially no discernable effects noticed between pipe material or pipe age. Additionally, laboratory (field) trials using a Simmons Manufacturing Picher Pump and each of the aforementioned pipe specifications were conducted at the University of South Florida (Tampa, FL, USA) to determine the practical pumping limit for these systems. Results from the pumping trials indicated that the practical pumping limit- the greatest height at which a reasonable pumping rate could be consistently sustained with only modest effort, as perceived by the person pumping- for a Pitcher Pump is around nine meters (9 meters when using 1.25-inch internal diameter GI or PVC pipe and 9.4 meters when using 2-inch internal diameter PVC pipe). Therefore, results from this research present two pieces of evidence which suggest that the practical water-lifting limit of manually operated suction pumps is somewhere around nine meters (at sea level), implying that reconsideration of the seven-meter suction lift limit commonly reported in the field might be warranted.
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Choi, Dong-Won. "Detection of pathogenic Aeromonas spp. from a simulated water distribution system using PCR." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1189409.
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Recently the EPA placed Aeromonas hydrophila on the Candidate Contaminant List (CCL). It has long been known to be a pathogen of cold blooded animals and now is a suspected human opportunistic pathogen as well. Among the various virulence factors produced by A. hydrophila, the cytolytic enterotoxin (AHCYTOEN) is by far one of the most important contributors to the pathogenicity of the organism. This factor is also produced by other pathogenic Aeromonas spp. In this study, PCR technology was used to detect AHCYTOEN gene from a simulated water distribution system. A set of primers was selected to amplify the unique sequence of a pathogenic island, AHCYTOEN gene. To examine the sensitivity of the PCR, serial dilutions of pure A. hydrophila culture were tested. The PCR technique used was sensitive enough to detect samples containing less than 10.0 cells/ml. Source water, bulk water, and simulated distribution biofilm samples were examined for the gene. Biofilm and bulk water samples exposed to raw source water were collected on 4 occasions during a 24-day period. PCR technology detected the AHCYTOEN gene from 100 % of the bulk water samples and 85% of tightly bound biofilm (TB) samples from a simulated water distribution system while no positive results were observed in loosely bound biofilm samples (LB). After the inlet line of the system was changed to normally treated distribution water, 11 biofilm samples were collected on 3 occasions during 15 day sampling period along with bulk water samples. No positive results were observed from the bulk water and LB samples while 91% of TB samples tested for the presence of the gene. No significant difference was observed in detection by PCR from biofilm samples before and after the switch to chloraminated water.Department of Biology
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Cochran, Jeff W. "Evaluation of pre and post treatment filtration performance of Kinetico Macrolite ceramic media compared to traditional sand/anthracite and GAC filters in drinking water treatment process." Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2008d/cochran.pdf.
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Thesis (Ph. D.)--University of Alabama at Birmingham, 2008.Additional advisors: Robert A. Angus, Joe J. Gauthier, Jason T. Kirby, Robert W. Peters. Description based on contents viewed June 12, 2008; title from title screen. Includes bibliographical references (p. 85-87).
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Garand-Sheridan, Anne-Marie. "Evaluation of novel polyethersulfone membranes developed using charged surface modifying macromolecules for the removal of pharmaceutically active compounds and endocrine disrupting compounds from drinking water." Thesis, University of Ottawa (Canada), 2008. http://hdl.handle.net/10393/27686.
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The increasing concern over potential health effects of pharmaceutically active compounds (PhACs) and endocrine disrupting compounds (EDCs) in drinking water has led to an increase in assessment of drinking water treatment plant efficiencies at removing these emerging micropollutants. For the most part, tight commercial membrane processes such as nanofiltration (NF) and reverse osmosis (RO) successfully eliminate PhACs and EDCs, however these are costly processes and infrequently implemented in North American treatment facilities. The more frequently used microfiltration (MF) and loose ultrafiltration (UF) membranes are ineffective in the removal of these compounds.
This thesis focuses on developing tight charged ultrafiltration (UF) membranes which could effectively remove PhACs and EDCs from drinking water without compromising flux and cost. The approach centers on developing the membrane surface charge by incorporating charged surface modifying macromolecules (CSMMs) as additives. Four CSMMs (MDI-PPG-HBS, MDI-PEG200-HBS, MDI-PEG400-HBS, MDI-DEG-NDS) were evaluated at three different casting conditions for poly(ether sulfone) (PES) based membranes. The modified membranes were compared to controls (without CSMMs) and one commercial membrane (NF270, Dow/Filmtec). Membrane properties including flux, molecular weight cut off, surface porosity, charge and hydrophilicity were evaluated and compared to the removal of four representative PhACs and EDCs (sulfamethazine, carbamazepine, bisphenol A and ibuprofen) at the mg/L-level.
The experimental membranes only achieved a temporary partial removal of the PhACs and EDC tested, thus further development is required. Given the temporary target compound removal and the large membrane pores, size exclusion and charge repulsion are not the dominant removal mechanism. From the removal pattern, and the fact that removal increased with increasing solute hydrophobicity, it is assumed that initial removal is caused by adsorption to the membrane. The membranes developed were tight by conventional ultrafiltration standards but did not achieve the performance desired.
In general, it was found that the CSMM-modified membranes did not significantly outperform the control membranes. CSMM-modified membranes tested generally produced less hydrophilic membranes with increasing pre-gelation time or PES concentration, in comparison to the control membranes. Pre-gelation time (i.e., three minutes versus no pre-gelation time) increases membrane porosity, and therefore flux is increased, without compromising removal. Increased PES concentration (i.e., 20% PES in comparison to 18% PES) yields more distinct effects from the different CSMMs. From these results, the most promising casting condition appears to be 20% PES and the CSMMs achieving the best removal are MDI-PEG 400-HBS and MDI-PPG-HBS. As increased surface porosity was achieved, continuing this line of research by optimizing membrane preparation conditions to decrease the pore size may produce the desired characteristics. It is recommended that further tests be performed at increased PES concentrations and with pre-gelation time to achieve better results.
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Mangum, Jacob E. "Sustainability of Community-Managed Rural Water Supply Systems in Amazonas, Peru: Assessing Monitoring Tools and External Support Provision." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/7055.
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Globally, there is still a large number of people without access to safe drinking water; a known health risk. In rural areas of countries like Peru, when potable water systems are built the responsibility for maintaining these systems is given to volunteer water committees. Despite its prevalence as a management model, there is a consensus that community management alone cannot ensure sustainable water service. Therefore, the overall goal of this research is to assess the sustainability of community-managed water systems in rural areas of the department of Amazonas, Peru. Specifically, this research examines two mechanisms that have been shown to improve the sustainability of rural water systems: 1) monitoring for asset management and service delivery, and 2) provision of long-term external support.
In Amazonas, three sustainability assessment tools have been used recently to monitor the service level and management of water systems. These assessment tools are: the Rural Water and Sanitation Information System (SIASAR, in Spanish), Tracers in Rural Water and Sanitation (Trazadores, in Spanish), and the Diagnostic Survey for Water Supply and Sanitation (Diagnostico, in Spanish). The three tools were assessed using a question mapping technique as well as a sustainability assessment tool evaluation matrix. This analysis identified the SIASAR assessment tool to be the most appropriate for ensuring sustainability of rural water supply systems.
This research also used the data collected with the SIASAR and Trazadores assessment tools to assess the state of community-managed rural water systems in Amazonas. The analysis showed that 81% of systems in the SIASAR analysis and 58% of systems in the Trazadores analysis have deficiencies that are beyond the ability of the water committee to overcome.
In recent years, the Peruvian government has prioritized the creation of an office in each district dedicated to providing external technical support to local water committees. This office, called the Área Técnica Municipal de Agua y Saneamiento (ATM), is charged with formalizing and training water committees which are given the name, Juntas Administradoras de los Servicios de Saneamiento (JASS).
In order to examine the provision of long-term external support provided by the ATM to the JASS, field research was conducted in six districts in Amazonas. Valuable anecdotal evidence was provided by the field research that helped to form recommendations for strengthening the capacity of the ATM office at the local municipal level.
The results of this research demonstrate that currently a large number of community-managed rural water systems in Amazonas are not sustainable but that the prioritization of monitoring and external support is an encouraging sign. If these mechanisms continue to be prioritized then it is highly likely that water systems throughout Amazonas and Peru will become more sustainable, bringing benefits to millions of Peruvians in rural areas.
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Roque, Jennifer C. "Evaluation of an On-Line Device to Monitor Scale Formation in a Brackish Water Reverse Osmosis Membrane Process." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5470.
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A modified two-element membrane pressure vessel assembly has been used to monitor process operational changes in a full-scale reverse osmosis (RO) water treatment plant (WTP). This study evaluated the effectiveness of the assembly as an on-line monitoring device intended to detect scale formation conditions when connected to an operating RO process train. This study was implemented to support the requirements of a larger University of Central Florida (UCF) research project ongoing at the city of Sarasota's Public Works and Utilities (City) water treatment facilities located in Sarasota, Florida. During the time-frame of this study, the City was in the process of eliminating their sulfuric acid feed from the pretreatment system of their existing 4.5 million gallon per day (MGD) RO membrane process. The City was motivated to eliminate its dependence on sulfuric acid to reduce operating costs as well as reduce operation health and safety risks associated with the use of the acid as a pretreatment chemical. Because the City was concerned with secondary process impacts associated with acid elimination, additional measures were desired in order to protect the full-scale process. This thesis reports on the design, fabrication and installation of a third-stage two membrane element pressure vessel “canary” sentinel monitoring device (Canary), its effectiveness as an on-line scaling monitor during full-scale acid elimination, and presents the results of the study. The Canary sentinel device was controlled using the normalized specific flux of the two membrane elements fed by a portion of the second stage concentrate of one of the City's full-scale RO process skids. Although the Canary demonstrated the ability to detect changes in an RO process operation, scaling did not occur under the conditions evaluated in this study. An autopsy of one of the Canary elements revealed that no scaling had occurred during the acid elimination process. Therefore, the Canary was found to be useful in its function as a sentinel, even though no scaling was detected by the device after acid elimination at the City's full-scale plant had been accomplished.ID: 031001503; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Steven J. Duranceau.; Title from PDF title page (viewed July 26, 2013).; Thesis (M.S.Env.E.)--University of Central Florida, 2012.; Includes bibliographical references (p. 70-73).
M.S.Env.E.
Masters
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Environmental Engineering
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Silva, Marina Costa da. "Avaliação de processo de carbonatação de agua de coco (Cocus nucifera L.)." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254532.
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Orientador: Jose de Assis Fonseca FariaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A agua de coco verde (Cocus nucifera L.) e bem conhecida por suas propriedades nutritivas, hidratantes e de baixos teores de gordura. Outra bebida com grande participacao no mercado de bebidas no Brasil e o refrigerante, bebida contendo dioxido de carbono (CO2) na sua formulacao. A adicao de CO2 proporciona maior vida e refrescancia para a bebida, alem de contribuir para uma alimentacao mais segura, inibindo o desenvolvimento de microrganismos aerobios. O objetivo deste estudo foi o desenvolvimento de uma bebida carbonatada a base de agua de coco verde e avaliacao do processo de carbonatacao dessa bebida. Diferentes formulacoes foram avaliadas sensorialmente, fixando-se inicialmente o pH em 4,4 e variando-se o volume de carbonatacao e o valor de solidos soluveis (0Brix). A bebida formulada foi clarificada, pasteurizada (90 °C/30s), resfriada, carbonatada e envasada em garrafas de polietileno tereftalato (PET) e armazenadas a temperatura ambiente. Para o processo de clarificacao e carbonatacao, avaliou-se diferentes tipos filtros e de carbonatadores. A bebida carbonatada foi avaliada atraves de analises fisico-quimica, microbiologica e sensorial pos processo e durante a estocagem. Quando a agua de coco carbonatada possuia volume de carbonatacao entre 4,1 a 4,3, 60% dos consumidores consideraram a quantidade de solidos soluveis de 8,2 como ideal de docura e 38,87% preferiram 7,2 oBrix. O processo de carbonatacao criou um ambiente seletivo para microrganismos na agua de coco carbonatada. O baixo pH e o ambiente de baixa tensao de oxigenio favoreceu o crescimento de leveduras e bacterias lacticas. Os resultados desta pesquisa sugeriram que o oxigenio atua fortemente sobre as alteracoes na cor da agua de coco in natura, pasteurizada e carbonatada, e em alguns casos aparecendo cor ligeiramente rosada e/ou marrom
Abstract: The coconut water (Cocus nucifera L.) is well known for its nutritional properties, high hydrating power and low fat levels. Another beverage with great participation in soft drinks market is the carbonated soft drinks, which is a traditional drink containing carbon dioxide (CO2) in its formulation. The addition of CO2 provides more life and greater refreshing to the beverage, besides contributing to a safer food, and inhibiting the development of aerobic microorganisms. The objective of this study was the development of a soft drink based on coconut water and the evaluation of process for the carbonation of coconut water and its shelf life study. Different formulations were sensory evaluated. The coconut water was standardized to pH 4,4 and settled the range of volume carbonation and soluble solids. The drink formulated was clarified, pasteurized (90°C/30s), cooled, carbonated and bottled in plastic bottles (PET) and stored at room temperature. Before heat processing clarification filters were tested and after this two carbonation equipments were tested and evaluated. The shelf life was followed by physicalchemical, microbiological and sensorial analysis. When the formulation of coconut water presented carbonation between 4.1 to 4.3, 60% of consumers considered the amount of soluble solids of 8.2 oBrix as ideal for sweetness but 38.87% preferred 7.2. The process of carbonation created a selective environment for microorganisms. Also the low pH and the environment of low oxygen tension favored the growth of yeasts and lactic bacteria. The growth of lactic acid bacteria in coconut water was favored by the nutrient-rich medium such as amino nitrogen. It was observed that oxygen acted strongly on the appearance of coconut water, both in nature, pasteurized, and carbonated, forming pink or brown colors
Mestrado
Mestre em Tecnologia de Alimentos
46
Tissier, Adeline. "Evaluation de l'état de viabilité et du pouvoir d'infectiosité de trois micro-organismes pathogènes pour l'homme (bactérie Campylobacter, virus Adenovirus et parasite Cryptosporidium) détectés dans des échantillons d'eaux destinées à des fins alimentaires." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0034/document.
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L'objectif de ce travail a consisté à (i) déterminer l'occurrence et (ii) à étudier le comportement de différents micro-organismes pathogènes pour l'Homme reconnus comme responsables d'épidémies d'origine hydrique dans des ressources (eaux de surface et eaux de nappes) et des eaux traitées de plusieurs collectivités situées le long de la Moselle. Trois agents microbiologiques aux propriétés morphologiques et intrinsèques très différentes ont été étudiés: des bactéries (C. jejuni et C. coli), des virus entériques (adénovirus humains dont les adénovirus entériques), des parasites (C. parvum, C. hominis, C. meleagridis). Après avoir mis en place différentes méthodologies permettant leur détection, leur quantification et la révélation de leur viabilité et/ou leur infectiosité, nous avons montré que l'eau de la Moselle était largement contaminée par ces pathogènes à des concentrations variables selon la période de l'année. Ainsi par exemple, il a été retrouvé des bactéries C. jejuni plus fréquemment en été que pendant la période hivernale alors que l'inverse a été observé pour les adénovirus humains. Les résultats d'occurrence au niveau des nappes alluviales étudiées ont montré que malgré une protection liée à la filtration naturelle de l'eau, elles pouvaient être contaminées par des campylobacters viables et des adénovirus entériques. Concernant les eaux traitées, plusieurs signatures génomiques liées à ces deux derniers agents (bactérien et viral) ont été révélées par des outils de biologie moléculaire sans qu'un risque en lien avec la viabilité et l'infectiosité puisse être établi. Dans ces eaux, les expérimentations d'inactivation ont clairement montré la grande sensibilité de ces deux agents au traitement chloré mais pas celle des parasites Cryptosporidium qui s'avèrent être les pathogènes les plus résistants quel que soit le milieu ou la température d'incubationThe aim of this study was (i) to determine the occurrence and (ii) to study the behavior of different microorganisms known to cause human waterborne outbreaks in raw waters (surface water and groundwater) and treated water of several reservoirs along the Moselle river. Three pathogens were studied: bacteria (C. jejuni and C. coli), enteric viruses (human adenoviruses which enteric adenoviruses), parasites (C. parvum, C. hominis, C. meleagridis). Because of these micro-organisms have different properties such as size, various methodologies were used for their detection, quantification and viability and/or infectivity. In the study of occurrence we showed that the Moselle river was heavily contaminated by these pathogens in varying concentrations depending on time of the year. For example it was found bacteria C. jejuni more frequently in summer than during winter while the reverse was observed for human adenoviruses. The results obtained in groundwater showed that despite a protection linked to the natural filtration of water, they could be contaminated with viable campylobacters and enteric adenoviruses. In the treated water, several genomic signatures associated with these two agents (bacterial and viral) were revealed by molecular biology tools without any risk related to the viability and infectivity can be established. In these waters, the inactivation experiments clearly showed the high sensitivity of these two agents to chlorination but not the parasite Cryptosporidium, which known to be the most resistant pathogens, whatever the type of water or incubation temperature
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Morton, Samuel R. "Development and Evaluation of an Aquifer Capability Screening Tool Pilot Study: Clarence-Rockland, Ontario." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32569.
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Increased development pressure led the United Counties of Prescott and Russell to seek development of a GIS-based Aquifer Capability Screening Tool (ACST). A Pilot ACST, developed by a project partner within this study, was made for the City of Clarence-Rockland, Ontario, and consists of several maps showing delineated areas where there may be groundwater limitations in terms of quality or quantity. This study gathered the chemistry data needed for the Pilot ACST from 127 domestic dug and drilled wells. The results showed exceedances of provincial health and aesthetic standards, which were then used to delineate maps for the Pilot ACST. An evaluation of the necessary data source and sampling scale for ACST development revealed that data gathered from existing reports was inadequate for various reasons and sampling scale should be on a grid 2x2 km2 or smaller. Further recommendations were provided for future ACST development studies.
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Constantino, Cristina de Abreu. "Avaliação da técnica 3Mtm Petrifilm tm para análises microbiológicas em água de consumo humano na região de Campinas." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254581.
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Orientador: Jose Luiz PereiraDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: No Brasil, a Portaria MS nº. 518/2004 do Ministério da Saúde estabelece, entre outros parâmetros, a análise de coliformes totais, termotolerantes ou Escherichia coli (E. coli) e de bactérias heterotróficos para análise de água para consumo humano, em toda e qualquer situação, incluindo fontes individuais como poços, minas e nascentes. A Agência de Proteção Ambiental dos Estados Unidos (EPA) avalia métodos para diferentes aplicações ambientais, entre outras, para análise de água potável, que se aprovados, são publicados como métodos oficiais no Standard Methods for the Examination of Water and Wastewater. Este manual recomenda muitos princípios de reações e métodos para análise de água potável e é muito importantes que se compreendam as limitações e benefícios destes métodos antes de utilizá-los, para garantir a segurança e qualidade microbiológica da água de consumo humano. Os métodos convencionais de análise microbiológica de água para consumo humano requerem um mínimo de 24 horas de incubação, seguidos por procedimentos de confirmação dos resultados positivos, que duram entre 24-48 horas, o que gera uma demanda de métodos mais rápidos de análise. O uso das Placas 3M¿ Petrifilm¿ não está aprovado pela EPA, e, consequentemente, não está publicada no Standard Methods for the Examination of Water and Wastewater. Este estudo apresenta resultados comparativos do desempenho da tecnologia 3MTM Placas PetrifilmTM para contagem de Coliformes e E. coli (EC) e Contagem de Aeróbios (AC) contra as metodologias convencionais para as análises de bactérias do grupo coliformes (Endo) e para contagem padrão de bactérias heterotróficas (PCA), através do método de membrana filtrante e técnica de plaqueamento em profundidade, respectivamente, seguindo os procedimentos descritos no protocolo 821-B-03-004, da EPA. As amostras foram obtidas de dois rios que suprem o fornecimento de água potável (antes e após o tratamento na estação de abastecimento), dois poços e duas fontes na região da cidade de Campinas, estado de São Paulo, Brasil. A água bruta dos rios foi utilizada para contaminar a água potável, e em seguida, foi realizado estresse por cloração, (0.1mg/L ¿ 5 minutos); a água dos poços e fontes estava naturalmente contaminada. Parâmetros físico-químicos foram avaliados. A mediana das contagens de coliformes e E. coli para água de consumo humano oriunda das estações de tratamento, com as 3MTM Placas Petrifilm EC foi igual a 1,9085 e para o meio Endo igual a 1,8603. O resultado do teste de Mann-Whitney foi W = 2786,5 o que demonstrou que não se pode rejeitar a igualdade dos métodos, já que W é maior do que 2525,0. O método Petrifilm EC apresentou menor variabilidade com pvalor = 0,014, com menor desvio padrão para o método EC (0,16), do que o método Endo (0,29) e maior precisão, com Coeficiente de variação (CV) = 8,43 para EC x CV = 15,91 para ENDO. Para amostras de água de fontes e poços não tratados, 40 resultados de contagens de coliformes foram avaliados e o método 3MTM Petrifilm EC apresentou recuperação estatisticamente inferior do que o método de referência, porém com maior precisão com CV=12, 26 para o método EC x CV = 16,44 para o método ENDO. Para contagens de bactérias heterotróficas, as amostras das três matrizes água foram analisadas conjuntamente. Não houve diferença na recuperação com o método 3MTM Petrifilm AC, pois W = 8455,5 é maior do que 8145, 0, com medianas de 2,0294 e 2,0212 para o método PCA, com p-valor de 0,253. O desvio padrão de 0,40 para o 3MTM Petrifilm AC e 0,49 para o método PCA demonstram que os métodos apresentaram recuperação muito similar das colônias e superioridade na precisão do método 3MTM Petrifilm AC, com CV = 19,78 x CV = 25,76 para o método PCA. Observou-se que não houve diferença estatística significativa e que há uma forte correlação entre os métodos convencionais e as placas 3MTM Petrifilm. A técnica 3MTM Petrifilm é rápida, padronizada, confirmatória e precisa e com base nestes resultados sugere-se que pode ser utilizada como um método prático para análise de bactérias heterotróficas, coliformes e E. coli em água de consumo humano, alternativamente à metodologia convencional, atendendo à demanda das empresas de alimentos, bebidas e abastecimento de água
Abstract: In Brazil the normative MS nº. 518/2004 of Health Agency establishes, among others parameters, the analysis of total, thermotolerant coliforms or Escherichia coli (E coli) and of heterotrophic bacteria for drinking water, including springs, wells and other sources of human drink water. Many principles of reactions are recommended for water potability analysis in the Standard Methods for the Examination of Water and Wastewater that proclaim the validated method for water analysis, sand are very important to understand the limitations and benefits of these methods before the use of these, to guarantee the security and microbiological quality of the human drinking water. The US Environmental Protection Agency (EPA) evaluates methods for many environmental uses, between others, to drinking water analysis, that been approved will be published as official methods in the Standard Methods for the Examination of Water and Wastewater. This Standard recommend that many reaction principle¿s and methods for drinking water analysis and is very important that be understood the limits and benefits of those methods before using it, for warranty the safety and microbiological quality of human drinking water. The conventional methods of microbiological water analysis of human consumption requires a minimum of 24 hour of incubation, followed for confirmatory procedures of the positive results, that last between 24-48 hours, what it generates a demand of faster methods of analysis. The use of 3M¿ Petrifilm¿ Plates is not approved by the EPA and consequently is not published in the Standard Methods for the Examination of Water and Wastewater. This study shows comparative results from the performance of the technology 3MTM PetrifilmTM Plates for counting of coliforms and E. coli (EC) and counting of aerobic organisms (AC) versus the conventional methodologies for the analyses of coliforms bacteria (Endo) and for standard counting of heterotrophic bacteria (PCA), through the method of membrane filtration and pour plate technique, respectively, following the protocol EPA 821-B-03-004 procedures. Samples were obtained from two rivers that are suppliers of drinking water (prior and after the supplier station treatment), two wells and two fountains in the Campinas city region, São Paulo state/ Brazil. The raw river water was used to spike drinking water, after chlorination stress [0.1mg/L ¿ 5 minutes]; wells and fountains were naturally contaminated. Physical-chemical parameters were evaluated. Median was EC = 1,9085 and Endo = 1,8603. The result from Mann-Whitney test was W = 2786,5, that shows the equality between methods can not be reject since W is > 2525,0. Petrifilm method shows lower variability with p-value = 0,014, with lower Standard Deviation to EC (0,16) than Endo (0,29) and higher precision, with CV = 8,43 for EC vs. CV = 15,91 for ENDO. For the untreated water from wells and fountains, 40 coliforms results were evaluated and EC results were statistically different and lower than the reference method, bur higher precision with Coefficient of Variation (CV) = 12, 26 for EC method vs. CV = 16,44 to ENDO method. For heterotrophic counts, the samples for 3 matrices were analyzed together. There is no recovery difference for 3MTM Petrifilm AC method since W = 8455,5 greater than 8145,0 with medians of 2,0294 and 2,0212 for PCA method, with a p- Value of 0,253. The Standard Deviation of 0,40 for 3MTM Petrifilm AC and 0,49 for PCA method shows that both methods presents a very similar recover of colonies and the superiority of precision of the 3MTM Petrifilm AC method, with CV = 19,78 vs. CV = 25,76 for PCA method. Was observed that there is no statistic significant difference and there is a strong correlation between the traditional and 3MTM Petrifilm Plates. The 3MTM Petrifilm technique is rapid, standardized, confirmatory and precise and based in these results should be suggested that it can be used as a practical method for heterotrophic bacteria, coliforms and E. coli analysis in human drinking water, alternatively to the conventional methodology, attending the demand of the companies of food, beverages and water supply stations
Mestrado
Engenharia de Alimentos
Mestre em Ciência de Alimentos
49
Viana, Demétrius Brito. "Contribuições para a construção de modelos de estimativa de riscos à saúde associados à transmissão de Giardia e Cryptosporidium via abastecimento de água para consumo humano." Universidade Federal de Viçosa, 2011. http://locus.ufv.br/handle/123456789/3780.
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Previous issue date: 2011-12-21Conselho Nacional de Desenvolvimento Científico e Tecnológico
This objectives of this work were: (i) to statistically characterize turbidity datasets of 44 water treatment plants (WTP), (ii) to evaluate the performance these 44 WTPs in achieving drinking-water turbidity standards, and (iii) to estimate risks of infection associated Cryptosporidium and Giardia in drinking-water, in case study applied to the University of Viçosa WTP (UFV WTP). The analysis of turbidity databases of raw and treated water of the 44 WTP showed that the hypotheses of data randomness, independence, stationarity and homogeneity were, in general, rejected. With few exceptions, turbidity data of raw and treated water were characterized by positive asymmetry. Raw water data showed the highest coefficients of skewness and kurtosis. Statistical tests confirmed the non-normality of all turbidity datasets analyzed, and indicated that most of them could be described by lognormal distribution. The standard of 0,15 NTU for filtered water was very rarely achieved in most WTP. Although a few WTP showed a high proportion of data with turbidity below 0,30 NTU, the actual percentage of WTP that met this standard was low. In turn, the standard of 0,50 NTU was achieved by half the WTP, often in more than 80% of data, and the 1,0 NTU standard was systematically attained in almost all WTP. Risks were estimated by stochastic modeling (Monte Carlo simulation), using the UFV WTP database, including information on the occurrence of Cryptosporidium and Giardia in the source water, and on turbidity removal. Models of Quantitative Microbiological Risk Assessment (AQRM) were constructed from these data and from literature information on: (i) dose-response models; (ii) recovery efficiency of the protozoa laboratory methods; (iii) relationships between (oo)cysts removal and turbidity, (ii) drinking-water consumption rates. Different AQRM models resulted in wide variations of risk estimates. Sensitivity analysis showed that the variables with the greatest impact on risk estimates were the (oo)cysts concentration in raw water, (oo)cysts removal by water treatment, and water consumption rates, indicating the need for a careful characterization these variables.
Esse trabalho objetivou: (i) caracterizar estatisticamente bancos de dados de turbidez de 44 estações de tratamento de água (ETAs); (ii) avaliar o atendimento dessas 44 ETAs aos padrões e critérios de turbidez de água tratada; e (iii) estimar riscos de infecção associados aos protozoários Cryptosporidium spp e Giardia spp. em água para consumo humano, em estudo de caso aplicado a ETA da Universidade Federal de Viçosa. A análise de bancos de dados de turbidez da água bruta e tratada (decantada e filtrada) das 44 ETAs, revelou que as hipóteses de aleatoriedade, independência, estacionariedade e homogeneidade dos dados foram, em geral, rejeitadas. Salvo poucas exceções, os dados de turbidez de água bruta e tratada foram caracterizados por assimetria positiva. Os dados referentes à água bruta apresentaram os maiores coeficientes de assimetria e de curtose. Testes estatísticos confirmaram a não normalidade de todas as séries de dados de turbidez analisadas e indicaram que a maioria destas poderia ser descrita por distribuição lognormal. O limite de 0,15 uT na água filtrada foi rarissimamente alcançado na maioria das ETAs avaliadas. Embora algumas ETAs tenham alcançado elevada margem de dados com turbidez abaixo de 0,30 uT, o percentual de ETAs que atendeu este limite foi baixo. Por sua vez, o padrão de 0,50 uT foi atingido por metade das estações com frequência superior a 80% dos dados, e o limite de 1,0 uT foi sistematicamente atendido pela quase totalidade das estações. A estimativa de riscos foi realizada por modelagem estocástica (simulação de Monte Carlo), utilizando o banco de dados da ETA UFV, incluindo informações sobre ocorrência de Cryptosporidium spp. e Giardia spp. na água bruta e remoção de turbidez. Modelos de Avaliação Quantitativa de Risco Microbiológico (AQRM) foram construídos a partir desses dados e informações de literatura sobre: (i) modelos dose-resposta; (ii) taxa de recuperação das técnicas laboratoriais de pesquisa de protozoários, (iii) modelos de estimativa de remoção de (oo)cistos em função da turbidez; (iv) estimativas de consumo de água. Os diferentes arranjos de modelos de AQRM resultaram em amplas variações nas estimativas de risco. Testes de análise de sensibilidade revelaram que as variáveis de maior impacto na estimativa de risco foram a concentração de (oo)cistos na água bruta, a remoção de (oo)cistos no tratamento da água e o consumo de água, indicando a necessidade de caracterização criteriosa dessas variáveis.
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