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Treatment of Colorado River water with ozone, ferric chloride and Cat-Floc T-2Di Domizio, Thomas John, January 1990 (has links) (PDF)
Thesis (M.S. - Civil Engineering and Engineering Mechanics)--University of Arizona, 1990. / Includes bibliographical references.
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High-frequency sensing of Clear Creek water quality mechanisms of dissolved oxygen and turbidity dynamics, and nutrient transport /Loperfido, John Vincent. Schnoor, Jerald L. Just, Craig L. January 2009 (has links)
Thesis supervisor: Jerald L. Schnoor. Thesis supervisor: Craig L. Just. Includes bibliographic references (p. 186-196).
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Estudo dos metodos : floculação em carbonato de calcio e adaptação das tecnicas de filtração em membrana e separação imunomagnetica para a detecção de Cryptosporidium e Giardia em amostras hidricas / Methods studies : calcium carbonate floculation and adptation of membrane filtration and immunomagnetic separation techniques for Cryptosporidium and Giardia detection in water samplesCantusio Neto, Romeu 28 March 2008 (has links)
Orientador: Regina Maura Bueno Franco / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T22:08:19Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008 / Resumo: A veiculação hídrica tem sido considerada uma das principais vias de transmissão de giardiose e criptosporidiose sendo implicada na ocorrência de vários surtos de gastroenterites, em vários países nos últimos anos. Diante deste panorama, no Brasil foi emitida Portaria 518/04 (Ministério da Saúde), que recomenda a pesquisa destes protozoários em água de consumo humano. Por este motivo, o objetivo deste estudo foi realizar um estudo comparativo entre as metodologias de concentração já existentes: Filtração em Membrana (FM) e Floculação em Carbonato de Cálcio (FCC), tecendo uma análise crítica das mesmas e verificando-se a sua aplicabilidade em amostras naturais de água superficial do Rio Atibaia. Este estudo foi conduzido em duas etapas: na primeira, foram realizados 52 experimentos, visando analisar o desempenho dos métodos propostos determinando-se a precisão inicial em amostras de água reagente inoculadas com suspensões comerciais de cistos e oocistos Easy Seed® (Biotecnology Frontiers, Austrália), aplicando-se ou não a etapa de purificação mediante o uso da separação imunomagnética. Quando foram avaliadas amostras do rio Atibaia, a suspensão comercial de cistos e oocistos utilizada para a contaminação artificial foi Color Seed® (Biotecnology Frontiers, Austrália). Em uma segunda etapa, um total de 36 experimentos foi conduzido com o objetivo de se avaliar o comportamento dos mesmos métodos frente a fatores interferentes, característicos da matriz de água bruta superficial, entre eles a turbidez. Nos experimentos controle com amostra de água reagente, a metodologia de FM recuperou mais organismos (21,5 % dos oocistos e 25,0 % dos cistos), quando comparada com a metodologia de FCC (5,3 % e 5,8 % dos oocistos e cistos, respectivamente). A inclusão da etapa de purificação por separação imunomagnética (IMS) não resultou num aumento na recuperação de cistos e oocistos nestas metodologias (FM e FCC). Nos experimentos com amostras de água do Rio Atibaia, de uma maneira geral, a metodologia de FCC apresentou melhor desempenho de recuperação dos organismos e quando incluída a etapa de IMS, uma melhora ocorreu apenas para a recuperação de cistos de Giardia spp. Quando avaliada amostras de água bruta superficial do rio Atibaia em condições de turbidez até 50 NTU a etapa de purificação por IMS acarretou uma maior eficiência de recuperação de cistos de Giardia spp. e oocistos de Cryptosporidium spp., para as duas metodologias de concentração. Quando a turbidez das amostras foi superior a 50 NTU, uma melhora da recuperação ocorreu apenas para Cryptosporidium spp, utilizando-se o método de FM. Assim, ambas as metodologias avaliadas, mostraram-se eficientes para serem aplicadas em um monitoramento desses protozoários em amostras hídricas, mesmo em situações de alta turbidez. A etapa de purificação pela separação imunomagnética nem sempre apresentou um ganho na recuperação dos organismos e, as variações nos valores de recuperação para ambos os protozoários, são inerentes aos protocolos utilizados e também associados à matriz analisada. A FM é indicada pela praticidade, tempo e resultados, podendo auxiliar para o conhecimento da ocorrência destes patógenos e assim, minimizar a possibilidade de sua transmissão mediante veiculação hídrica / Abstract: The waterborne transmission route of giardiosis and criptosporidiosis has been considered the major one, causing the occurrence of several gastroenteritis outbreaks in several countries in the last years. Looking to this panorama, was published in Brazil the Governmental Decree 518/04 (Health Department), that recommends the research of these protozoa in water samples. For this reason, the goal of this study was to accomplish a comparative study between Membrane Filtration (MF) and Calcium Carbonate Flocculation (FCC) concentration methodologies, doing a critical analysis of both and verifying its apply in natural samples of Atibaia River superficial water. Two stages took place: in the first one, 52 experiments were carried out, aiming to analyze the performance of the methods proposed, determining the initial precision in samples of reagent water inoculated with commercial suspensions of cysts and oocysts (Easy Seed®-Biotecnology Frontiers Australia), applying or not the purification step by Immunomagnetic Separation. When natural water samples were evaluated, the commercial suspension of cysts and oocysts utilized for the artificial contamination was (Color Seed®-Biotecnology Frontiers Australia). In a second step, 36 experiments were carried out aiming to evaluate the behavior of the methods facing interferential factors, peculiar of the superficial raw water matrix, as turbidity. In the trial control with reagent water sample, the FM methodology recovered more organisms (21.5% of the oocysts and 25.0% of the cysts), in comparison to the FCC methodology (5.3% of the oocysts and 5.8% of the cysts). The purification step by Immunomagnetic Separation (IMS) did not show an improvement in the recovery of cysts and oocysts in these methodologies (FM and FCC). In the experiments with natural water performance of the organisms and when IMS step was included, an improvement occurred just for the recovery of Giardia spp. cysts. When superficial raw water of Atibaia river samples with turbidity up to 50 NTU were evaluated, the purification step by IMS showed higher efficiency in the recovery of Giardia spp. cysts and Cryptosporidium spp. oocysts, for both concentration methodologies. When the turbidity of the sample was over 50 NTU, a recovery improvement occurred just for Cryptosporidium spp, using the FM method. Thus, both methodologies showed efficiency in monitoring these protozoa in water samples, even in situations of high turbidity. The purification step by Immunomagnetic Separation not always showed gain in the recovery of the organisms and the variations in the values of recovery for both protozoa are inherent to the protocols that were used and also associated to the analyzed matrix. However, the FM method is indicated for its practicability, time and results, being able to help the knowledge of the occurrence of these pathogens and minimize the possibility of its transmission by waterborne route / Doutorado / Parasitologia / Doutor em Parasitologia
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Secagem convectiva e com radiação infravermelha de grãos de Moringa oleifera Lam / Convective drying with infrared radiation of Moringa oleifera L. grainsNascimento, Vânia Rosal Guimarães, 1983- 25 August 2018 (has links)
Orientadores: João Domingos Biagi, Rafael Augustus de Oliveira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-25T15:21:52Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: A radiação infravermelha aplicada na secagem de produtos agrícolas e alimentos apresenta a vantagem de aquecer diretamente o produto exposto, com poucas perdas com aquecimento do ar circundante, promovendo maior eficiência energética e redução do tempo de secagem. O produto estudado nesta pesquisa foi grãos de Moringa oleifera Lam, que dentre suas múltiplas aplicações, destaca-se como coagulante natural no tratamento de água, devido a uma proteína catiônica de ação clarificante. Embora seja constatada a necessidade de utilização de grãos secos nesses processos, não se verificou na literatura científica recomendação das condições de secagem adequadas aos grãos para serem utilizados na solução coagulante. Neste sentido, o uso combinado da radiação infravermelha com ar aquecido pode ser viável tecnicamente e eficiente na secagem de grãos de Moringa oleifera Lam, mantendo a qualidade dos grãos para utilização em tratamento de água. O objetivo deste trabalho foi avaliar o potencial de aplicação da radiação infravermelha intermitente em associação com a secagem convectiva de grãos de Moringa oleifera L., quanto à eficiência de secagem, consumo energético e manutenção da qualidade dos grãos. Realizaram-se ensaios de secagem estudando os fatores temperatura e velocidade do ar, intensidade e tempo de aplicação da radiação infravermelha para definir aqueles que interferem no processo e seus níveis ótimos de operação. O aumento da intensidade da radiação infravermelha reduziu o tempo de secagem, o consumo de energia e propiciou maior eficiência na redução da turbidez de água quando esses grãos foram aplicados na produção de coagulante. A elevação dos níveis da velocidade do ar, por sua vez, diminuiu a taxa de secagem e aumentou o consumo de energia. O incremento da temperatura do ar de secagem provocou elevação da taxa de secagem, reduziu o tempo de secagem e contribuiu com a redução da turbidez de água sintética tratada com solução coagulante de grãos de Moringa oleifera L. O tempo de aplicação da radiação infravermelha aumentou a taxa de secagem e permitiu redução da turbidez de água sintética quando seus níveis foram aumentados. A difusividade efetiva variou entre 6,44x10-10 m² s-1 e 9,89x10-10 m² s-1. Os modelos de Fick e Midilli apresentaram melhores ajustes aos dados experimentais. A temperatura do ar e o tempo de aplicação da radiação infravermelha elevaram a temperatura do ar dentro do secador e a temperatura dentro dos grãos durante os ensaios de secagem. O tempo de aplicação da radiação infravermelha reduziu consideravelmente o consumo total de energia durante as secagens. A elevação do nível de temperatura do ar de secagem, no entanto, provocou proporcional aumento do consumo de energia. Constatou-se que a região do ponto central do planejamento experimental, temperatura do ar de 44°C e tempo de aplicação da radiação infravermelha de 3,4 min, apresentou a combinação entre os fatores com maior teor de proteína e que correspondeu maior remoção de turbidez quando esses grãos foram utilizados para produção de coagulante. Em relação à qualidade dos grãos de Moringa oleifera L., a secagem aumentou a concentração do teor de proteína, favoreceu a sedimentação dos sólidos devido à oxidação de lipídios e promoveu maior remoção da turbidez de água sintética tratada com solução a base desses grãos / Abstract: The infrared radiation applied for drying of agricultural products and foods presents the advantage of heating directly the exposed product, minimizing losses with heating of surrounding air, promoting grater energy efficiency and reducing in drying time. The product studied in this research was Moringa oleifera Lam grains, which among its many applications, stand out as a natural coagulant in water treatment, due to the presence of a cationic protein with clarifier action. Although it is observed the necessity to use dry grains in these processes, there was no recommendation in the scientific literature of appropriate drying conditions for grains to be used in the coagulant solution. In this way, the combined use of infrared radiation with heated air can be technically feasible and efficient in drying of Moringa oleifera L. grains, maintaining the quality attributes of grains for use in water treatment. This study aims to evaluate the potential application of intermittent infrared radiation in association with convective drying of Moringa oleifera L. grains, regarding the drying efficiency, energy consumption and maintenance of grains quality. Experimental runs were performed studying the factors air temperature, air velocity, infrared radiation intensity, and time of infrared radiation application to define those which have an effect on the process and its optimum levels of operation. The increased intensity of the infrared radiation reduced the drying time, energy consumption and propitiated greater efficiency in reducing the turbidity of water when these grains were applied in the coagulant production. Whereas elevated levels of air velocity decreased drying rate and increased energy consumption. The increase in the drying air temperature caused elevation of drying rate, decreased the drying time and contributed with turbidity reduction of synthetic water treated with coagulant solution of Moringa oleifera L. grains. The time of infrared radiation application increased the drying rate and allowed turbidity reduction of synthetic water when its levels were increased. The effective diffusivity ranged from 6.44x10-10 m² s-1 and 9.89x10-10 m² s-1. Fick and Midilli models showed better fit to the experimental data. Air temperature and time of infrared radiation application increased air temperature inside the dryer and the temperature inside the grains during drying experiments. The application of infrared radiation significantly reduced total energy consumption during drying. Increasing the level of air temperature caused a proportional increase in energy consumption. It was found that central point of the experimental design, air temperature of 44 °C and infrared time of 3.4 min, showed a combination of factors with higher protein content and corresponded to the highest turbidity removal when these grains were used for coagulant production. In relation to Moringa oleifera L. grain quality, drying increased the concentration of protein, favored the sedimentation of solids due to the oxidation of lipids and promoted greater removal of turbidity from synthetic water treated with these grains / Doutorado / Tecnologia Pós-Colheita / Doutora em Engenharia Agrícola
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Influence of Water Quality on Stony Coral Diversity and Net Community Productivity in the Florida KeysVega-Rodriguez, María 14 November 2016 (has links)
Worldwide, coral cover has declined at rates that have often exceeded 5% per year since the 1980’s. Populations of scleractinians (stony corals) in the Florida Keys reef tract have declined as well, with some communities declining at rates > 3% per year. Decreased water quality (e.g., steady increases in the ocean water temperatures and increased pollution, nutrients, or water turbidity due to coastal runoff) are commonly attributed to this decline. But actual linkages between variability and trends in these environmental parameters, and in stony coral diversity and ecosystem functions such as net community production, have not yet been well characterized.
With this research, I examined the influence of water quality (water temperature, nutrients and turbidity) on stony coral diversity and net community productivity in shallow-water reef ecosystems of the Florida Keys between 1996 and 2010. Differences in stony coral diversity in Florida Keys patch reefs with respect to sea surface temperature (SST) variability are evaluated in Chapter Two. Habitat-specific differences in stony coral diversity with respect to changes in a suite of environmental parameters (water turbidity, nutrients, water temperature and depth) are addressed in Chapter Three. Differences in daytime net community production and light-adapted stony coral photosynthetic efficiencies among three reef sites with different turbidity levels and seasons (May and October) are presented in Chapter Four.
Environmental parameters examined to characterize the differences in stony coral diversity across the Florida Reef Tract included satellite-derived sea surface temperature [SST] and Degree Heating Weeks [DHWs], field observations of bio-optical properties of the water, and nutrient concentrations. These parameters were compared with live coral cover and species richness, net community production, and coral photo-physiological observations.
In Chapter Two, I found that stony coral cover and diversity was higher in patch reefs of the Florida Keys relative to offshore and deeper reefs. Generally, patch reefs were characterized by intermediate to high SST variability (≥7.0°C2). Intermediate SST variance (7.0–10.9°C2) was correlated with higher diversity indices for patch reefs of the Upper (Shannon Diversity: 1.2–1.5) and Middle Keys (Species Richness: 13–19), suggesting that stony coral species in these habitats are either adapted to intermediate temperature ranges or thermal acclimation has taken place for individual colonies. Additionally, I found that found that years for which cold and warm-water extremes coincided (i.e., highest SST variance), such as 1997-98 and 2009-2010, led to significant reductions in both H’ and SR. Coral bleaching and mortality were associated with exposure to cold- and warm-water temperature extremes and the combination of both extremes were associated with reductions in stony coral diversity. The highest species richness and abundance were found in patch reefs of the Middle Keys, despite exposure to the warmest water-temperature anomaly events (as indicated by DHWs exceeding the coral bleaching threshold of 4) observed during the summers of 1998 and 2010.
In Chapter Three, I found that the environmental parameters that best explained the differences in stony coral diversity (species composition and abundance) on patch reefs of the Florida Keys were water turbidity, nutrients, surface water temperature, % surface oxygen saturation and chlorophyll a concentrations averaged over a period of 24 months, along with depth (F = 4.4, R2 = 0.66, R2adj. = 0.40, p < 0.05). Surface water turbidity and depth were the most relevant environmental parameters driving the differences in stony coral diversity (R2 = 0.17, p < 0.05, R2 = 0.10, p < 0.05, respectively). The influence of these environmental parameters decreased towards offshore shallow and deep reefs. In the Florida Keys, stony coral diversity was the highest at patch reefs of the Middle and Lower Keys where exposed to higher water turbidity and nutrients than those in the Upper Keys located in clearer waters. This suggests that, at long-term scales, corals in patch reef environments exposed to higher water turbidity and water temperature variabilities (as reported in Chapter Two) might be better able to withstand thermal and light-induced stress.
Moreover, a short-term study (described in Chapter Four) indicated that the net community production (NEP) was similar among sites with different water turbidity levels (i.e., Cheeca Rocks and Crocker Reef; Upper Keys and Sugarloaf Key; Lower Keys) and seasons (May or October). However, the light-adapted photosynthetic efficiencies (F/Fm’) varied spatiotemporally. The highest F/Fm’ values (0.57–0.69) were found at the nearshore patch reef of Sugarloaf Key, Lower Keys, in October 2012. At this patch reef, high light attenuation (Kd (488) = 0.12 m-1) was associated with absorption by colored dissolved organic matter and exacerbated by particulates following thunderstorms. The lowest F/Fm’ values (
This study represents a baseline against which future observations on coral reef biodiversity and net community production in the Florida Keys reef tract may be evaluated.
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Characterisation and desalination of typical South African abalone farm effluent sea waterSteynberg, Leander Duvan 12 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Nearly all South African abalone farms function on an intensive pump-ashore, flow-through system. Large volumes of sea water that are pumped ashore flow through abalone or kelp harvesting tanks and finally gravitate back to the ocean. If the effluent from an abalone farm can be desalinated without permanent membrane fouling, then sea water reverse osmosis (SWRO) technology can be integrated effectively with established abalone farms without having to increase the farms’ intake system capacities. Without the need to construct and maintain an intake system, the overall cost of desalination can be reduced. Therefore, the aim of this study was to determine the feasibility and viability of integrating a SWRO desalination plant with a typical South African abalone farm. The project focused on four areas of concern, namely:
- characterisation of typical South African abalone farm water
- SWRO desalination plant pilot study and membrane fouling behaviour
- general operation of a typical abalone farm and its implications for desalination
- cost estimates and implications for the integration of an SWRO desalination plant with an abalone farm
During a nine-month on-site investigation, sea water turbidity was reduced by up to 43% from a mean value of 0.82 NTU in the influent stream to 0.47 NTU in the combined effluent stream from the abalone tanks. Even with spikes in the influent turbidity, the turbidity of the combined effluent from all abalone tanks (excluding tank flush water) remained below 1 NTU. Dissolved organic carbon (DOC) in both the influent and combined effluent remained below 1 mg/litre.
Ultrafiltration (UF) was selected as pre-treatment to the reverse osmosis (RO) in order to minimise potential fouling of the RO membranes. Membrane compaction of both the UF and RO membranes contributed significantly to initial flux losses – as much as 18% for the polyethersulfone (PESM) UF membranes and 20% for the thin film composite (TFC) polyamide RO membrane. However, this is comfortably in line with typical compaction values quoted in the literature.
Without pre-flocculation, the UF was able to operate at a specific flux between 45 and 55 litre/m2/h (LMH) and recoveries ranging between 60 and 75%. Corresponding trans-membrane pressure (TMP) ranged between 0.59 and 0.76 bar. With ferric chloride pre-flocculation at a concentration of 3 mg/litre (as Fe3+) the UF could be operated at notably lower TMP values between 0.11 and 0.36 bar. These results indicate that provision should definitely be made for pre-flocculation when using UF as pre-treatment, despite the fact that the DOC concentrations and turbidity of the abalone farm effluent are quite low (DOC <1 mg/litre, NTU <1). It furthermore highlights the inability of DOC and turbidity alone to predict the membrane fouling potential of water.
A better indicator of membrane fouling potential, albeit not perfect, is the modified fouling index (MFI0.45). This index follows a linear trend with foulant concentration and serves as a good indicator of the filterability of water. On-site measurements showed an increase in mean MFI0.45 values from 29 s/litre2 for the influent to 48 s/litre2 for the effluent from the abalone tanks, thereby confirming the need for pre-flocculation as part of UF pre-treatment.
Chemically enhanced backwashing (CEB) of the UF membrane at least every 24 hours was found to be essential for its stable operation. Therefore, UF with pre-flocculation (3 mg/litre Fe3+) and regular CEB can be used effectively as pre-treatment method for the desalination of abalone farm effluent water.
An RO ‘feed-and-bleed’ system was used to simulate the typical performance of the last membrane in a full-scale RO membrane bank. This RO membrane performed well with no signs of extreme fouling. The membrane produced a good quality permeate – for the last membrane in a membrane bank – reducing the TDS of the RO feed from 33 493 mg/litre to 969 mg/litre. These results compared well with simulated values by Reverse Osmosis System Analysis (ROSA; an RO simulator by DOW), indicating a TDS reduction from 33 271 mg/litre to 1 409 mg/litre at a feed pressure of 56 bar, and overall recovery of 44%.
A steady performance of the RO membrane during the pilot study indicated that it is possible to desalinate abalone effluent water without notable permanent membrane fouling. A stable normalised flux rate of 8 LMH was achieved and RO membrane integrity remained intact with a salt rejection that ranged from 98.0 to 98.5%. No sudden reduction in permeate flux was observed as a result of fouling by unknown constituents present in the UF permeate. DBNPA (a non-oxidising disinfectant) was dosed once per week at a concentration of 10 – 30 mg/litre for 30 minutes. Scaling was controlled effectively by means of an antiscalant dosed at a concentration of 11 – 12 mg/litre in the feed stream. The CIP frequency was not optimised but a CIP frequency of once every 6 – 8 weeks appeared to be more than adequate to prevent permanent membrane fouling
Advantages of integrating an SWRO desalination plant with a South African abalone farm include:
- no lengthy and costly environmental impact assessment (EIA) is required to build a new intake system
- shared capital and operational cost of intake system
- dual incentive to keep constant good quality water flowing through the farm
- early warnings regarding occurrences such as algal bloom and red bait
- shared operational and management cost to keep pipelines clean
- electricity saved (pumps for intake system)
Disadvantages of integrating an SWRO desalination plant with a South African abalone farm include:
- will require diverting of the abalone tank wash water from regular effluent
- possible water ‘down-times’ due to maintenance operations on abalone farm
Based on information from the literature the fixed capital cost depreciation rate (FCCDR) typically contributes approximately 40% and the operation and maintenance (O&M) cost typically contributes 60% to the unit production cost (UPC) of desalinated water. Furthermore, a SWRO desalination plant’s intake system can contribute between 5% and 33% to the FCCDR, depending on the nature and design of the plant. Consequently, the intake system can contribute between 2% and 13% of the UPC of desalinated sea water. This implies possible cost savings of between R0.15/m3 and R2.37/m3 for the production of fresh water (depending on site-specific design factors) when desalinating sea water effluent from on-shore abalone tanks.
Integration of an SWRO desalination plant with a South African abalone farm is feasible and viable, provided that the necessary steps and precautions are taken to ensure a smooth and stable operation of the SWRO desalination plant. Cost savings on the part of all the stakeholders are possible if the correct contract can be negotiated. / AFRIKAANSE OPSOMMING: Byna alle Suid Afrikaanse perlemoenplase funksioneer op ‘n seewater deurvloeistelsel. Groot volumes seewater word aan wal gepomp en vloei deur die perlemoen of kelp-oes tenks. Hierdie water vloei dan uiteindelik terug na die oseaan as gevolg van swaartekrag. Indien die afvalwater van die perlemoenplase ontsout kan word sonder permanente membraanbevuiling kan seewater tru-osmose (SWTO)-tegnologie effektief met gevestigde perlemoenplase geïntegreer word sonder om die plase se water inname-stelsels se kapasiteite te vergroot. Sonder die behoefte aan uitbreiding en instandhouding van ‘n water inname-stelsel by so ‘n plaas behoort die totale koste van ontsouting aansienlik minder te wees. Die doel van hierdie studie was dus om die uitvoerbaarheid en lewensvatbaarheid van ‘n integrasie van ‘n SWTO ontsoutingsaanleg met ‘n tipiese Suid Afrikaanse perlemoenplaas te ondersoek. Ten einde dit te doen, het die projek op vier areas van belang gefokus, naamlik:
- karakterisering van tipiese Suid-Afrikaanse perlemoenplaas water
- SWTO ontsoutingsaanleg loodsstudie en membraan bevuilingsgedrag
- algemene bedryf van ‘n tipiese perlemoenplaas en die implikasies vir ontsouting
- kosteberamings en koste-implikasies met betrekking tot die integrasie van ‘n SWTO ontsoutingsaanleg met ‘n perlemoenplaas
Gedurende ‘n nege maande op-perseel ondersoek is seewater troebelheid verminder met tot 43% van 'n gemiddelde waarde van 0.82 NTU in die invloeistroom tot 0.47 NTU in die gekombineerde afvalwaterstroom wat die tenks verlaat. Selfs met skerp wisseling in die invloeistroom troebelheid, bly afvalwaterstroom troebelheid deurgaans onder 1 NTU met die uitsondering van tenk spoelwater. Opgeloste organiese koolstof (OOK) in beide die invloeistroom en die gekombineerde afvalwaterstroom het deurgaans onder 1 mg/liter gebly.
Ultrafiltrasie (UF) is gebruik as voorbehandeling vir die tru-osmose (TO) om sodoende potensiële bevuiling van TO membrane te minimaliseer. Membraan kompaksie van beide die UF en TO het merkbaar bygedra tot aanvanlike deurvloeiverliese – so veel as 18% vir die poli-etersulfoon (PESM) UF membrane en 20% vir die dun film saamgestelde (DFS) poli-amied TO membraan. Hierdie is egter gerieflik binne die tipiese kompaksiewaardes soos aangehaal in die literatuur.
Sonder flokkulasie was die UF in staat tot temperatuur aangepaste deurvloeitempo van tussen 45 en 55 liter/m2/h (LMH) teen herwinningstempo’s tussen 60 en 75%. Ooreenstemmende trans-membraandrukkings (TMD) het gewissel tussen 0.59 en 0.76 bar. Met ysterchloried voor-flokkulasie teen 'n konsentrasie van 3 mg/liter (as Fe3+) kon die UF teen merkbaar laer TMD waardes bedryf word – tussen 0.11 en 0.36 bar. Hierdie resultate dui daarop dat daar beslis voorsiening vir pre-flokkulasie gemaak moet word wanneer UF as voorbehandeling gebruik word, ten spyte van die feit dat die OOK konsentrasie en troebelheid van die afvalwater van die perlemoenplaas redelik laag is (OOK <1 mg / liter, troebelheid <1 NTU). Verder lig dit die onvermoë uit om OOK en troebelheid alleen te gebruik om membraanbevuilingspotensiaal van water te voorspel.
‘n Beter aanwyser van membraanbevuilingspotensiaal, alhoewel nie perfek nie, is die aangepaste bevuilingsindeks (MFI0.45). Hierdie bevuilingsindeks volg ‘n lineêre neiging met die konsentrasie van onsuiwerhede en dien as ‘n goeie aanwyser van die filtreerbaarheid van water. Op-perseel metings het getoon dat ‘n toename in gemiddelde MFI0.45 waardes van 29 s/litre2 vir die invloeistroom tot 48 s/litre2 vir die afvalstroom van die perlemoentenks die behoefte vir voor-flokkulasie as deel van UF voorbehandeling bevestig.
Chemies versterkte terugspoeling (CVT) van die UF membrane ten minste elke 24 uur is noodsaaklik gevind ten einde bestendige werking te verseker. Dus kan UF met voor-flokkulasie (3 mg/liter Fe3 +) en gereelde CVT effektief as voorbehandeling metode vir die ontsouting van perlemoenplaas afvalwater gebruik word.
‘n TO ‘voer-en-bloeistelsel’ is gebruik om die tipiese prestasie van die laaste membraan in ‘n volskaalse TO membraanbank te simuleer. Hierdie TO membraan het goed presteer sonder tekens van buitensporige membraanbevuiling. Vir die laaste membraan in ‘n membraanbank het die membraan goeie gehalte finale water gelewer – ‘n vermindering van die totaal opgeloste stowwe (TOS) van die TO voerwater van 33 493 mg/liter tot 969 mg/liter is behaal. Hierdie resultate het goed vergelyk met gesimuleerde waardes deur Reverse Osmosis Analysis System (ROSA, ‘n TO simulator deur DOW) wat ‘n TOS vermindering van 33 271 mg/liter tot 1 409 mg/liter by ‘n voerdruk van 56 bar en ‘n algehele herwinningstempo van 44% aandui.
‘n Bestendige werking van die TO membraan tydens die loodsstudie het getoon dat dit moontlik is om perlemoenplaas afvalwater te ontsout sonder merkwaardige permanente membraanbevuiling.
'n Stabiele genormaliseerde deurvloeitempo van 8 LMH is bereik en TO membraan integriteit het ongeskonde gebly met 'n sout verwerping wat gewissel het van 98.0 tot 98.5%. Geen skielike afname in finale water deurvloeitempo is waargeneem as gevolg van bevuiling deur onbekende onsuiwerhede in die UF finale water nie.
DBNPA (‘n nie-oksiderende ontsmettingsmiddel) is een keer per week teen ‘n ‘n konsentrasie van 10 – 30 mg / liter vir 30 minute gedoseer. Mineraal skaalvorming is effektief beheer deur die dosering van ‘n anti-skaalmiddel teen 11 – 12 mg/liter in die TO voerstroom. Die skoonmaak-in-plek (SIP) frekwensie is nie ge-optimeer nie, maar ‘n SIP een keer elke 6 – 8 weke is meer as voldoende gevind om mikrobiese bevuiling te voorkom.
Voordele van die integrasie van 'n SWTO ontsoutingsaanleg met 'n Suid-Afrikaanse perlemoenplaas sluit die volgende in:
- geen lang en duur omgewings impak ontleding (OIO) is nodig vir die bou van ‘n nuwe inname-stelsel nie
- gedeelde kapitaal en operasionele koste van inname-stelsel
- tweeledige aansporing om konstant goeie gehalte watervloei deur die plaas te verseker
- vroegtydige waarskuwings ten opsigte van gebeurtenisse soos rooigety
- gedeelde bedryfs- en bestuurskoste om voerpype skoon te hou
Nadele van die integrasie van 'n SWTO ontsoutingsaanleg met 'n Suid-Afrikaanse perlemoenplaas sluit die volgende in:
- vereis herleiding van perlemoentenk spoelwater weg van gereelde afvalwater
- moontlike watervloei-aftye weens instandhoudingsbedrywighede op die perlemoenplaas
Gebaseer op inligting uit die literatuur dra die vaste kapitaal koste waardeverminderings-koers (VKKWK) gewoonlik ongeveer 40% en die bedryfs- en instandhoudingskoste (B&I) ongeveer 60% by tot die produksiekoste per eenheid (PKE) van ontsoute water.Verder kan ’n SWTO ontsoutingsaanleg se inname-stelsel tussen 5% en 33% tot die VKKWK bydra afhangende van die aard en ontwerp van die aanleg. Gevolglik kan die inname-stelsel tussen 2% en 13% tot die PKE van ontsoute seewater bydra. Dit impliseer ‘n moontlike kostebesparing van tussen R0.15/m3 en R2.37/m3 vir die produksie van vars water wanneer die afvalwater van perlemoentenks ontsout word.
Integrasie van 'n SWTO ontsoutingsaanleg met 'n Suid-Afrikaanse perlemoenplaas is uitvoerbaar en lewensvatbaar indien die nodige stappe en voorsorgmaatreëls geneem is om ‘n vlot en bestendige werking van die SWTO ontsoutingsaanleg te verseker. Kostebesparings vir alle belanghebbendes (beleggers) is moontlik indien daar oor die korrekte kontrak onderhandel kan word.
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Aplicabilidade do método 1623 e do método de filtração em membranas para detecção de cistos de Giardia spp. e oocistos de Cryptosporidium spp. em amostras hídricas considerando diferentes faixas de turbidez, e estudo da etapa de purificação por separação imunomagnética : Applicability of method 1623 and membrane filtration method for detection of Giardia spp. cysts and Cryptosporidium spp. oocysts in water samples considering different levels of turbidity, and study of immunomagnetic separation phase / Applicability of method 1623 and membrane filtration method for detection of Giardia spp. cysts and Cryptosporidium spp. oocysts in water samples considering different levels of turbidity, and study of immunomagnetic separation phasePinto, Diego de Oliveira, 1987- 28 September 2018 (has links)
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Previous issue date: 2013 / Resumo: Os protozoários patogênicos Giardia spp. e Cryptosporidium spp. estão entre os principais contaminantes associados à veiculação hídrica e seu monitoramento em águas de abastecimento público é determinado pela Portaria n. 2.914/2011, do Ministério da Saúde do Brasil. Este trabalho foi dividido em duas partes. Na primeira, foi realizado um estudo da aplicabilidade do Método 1623 utilizando Filta-Max® (FMx) e Método de Filtração em Membranas (FM). Cistos de Giardia spp. e oocistos de Cryptosporidium spp. foram inoculados artificialmente em amostras de água bruta superficial proveniente do rio Atibaia, coletadas na cidade de Campinas/SP, Brasil, e agrupadas de acordo com faixas de turbidez. Cistos de Giardia spp. naturalmente presentes nas amostras foram detectados em todas as faixas de turbidez por ambos os métodos. O método de FM atendeu aos critérios de controle de qualidade analítica da USEPA em todas as faixas de turbidez. Não houve diferença estatística significativa entre os métodos de FMx e FM. Na segunda parte deste trabalho, foi feito um estudo da etapa de purificação por Separação Imunomagnética (IMS) no qual foi avaliado o desempenho dos procedimentos de dissociação: ácida e térmica; bem como investigado possíveis causas de perdas dos organismos-alvo durante execução desta etapa. A dissociação ácida apresentou maior média de eficiência de recuperação e precisão do que a dissociação térmica para cistos de Giardia spp.. Para oocistos de Cryptosporidium spp. não houve diferença estatística significativa. Após o procedimento de dissociação, tanto ácida quanto térmica, haviam cistos e oocistos aderidos às beads (micro-esferas magnéticas) que seriam descartadas de acordo com o protocolo padrão da IMS / Abstract: The pathogenic protozoa Giardia spp. and Cryptosporidium spp. are some the major waterborne contaminants and their monitoring in water supply is determined in Decree no. 2.914/2011, the Brazil¿s Ministry of Health. This study was divided in two parts. In the first, a study was conducted to evaluate the applicability of two methods for concentration of pathogenic protozoa Giardia spp. and Cryptosporidium spp. in water samples: Method 1623 using Filta-Max® (FMX) and Membrane Filtration (MF) Method. Giardia spp cysts and Cryptosporidium spp oocysts were artificially inoculated in samples of raw surface water from the Atibaia River, collected in Campinas/SP, Brazil, and grouped according to ranges of turbidity. Giardia spp. cysts naturally present in the samples were detected in all ranges of turbidity by both methods. The method of FM met the criteria for analytical quality control of USEPA in all ranges of turbidity. There was no statistically significant difference between the methods of FM and FMX. In the second part of this work, a study was made of the purification step by immunomagnetic separation (IMS) in which was evaluate the performance of the dissociation procedures: acid and heat, as well as investigating possible causes loss of target organisms during execution of this step. The acid dissociation showed higher mean recovery efficiency and accuracy than heat dissociation for Giardia spp.. For Cryptosporidium spp. difference was not statistically significant. After the dissociation procedure, both acid and heat, cysts and oocysts were still adhered to the beads (magnetic microspheres) that would be discarded, according to the standard protocol of IMS / Mestrado / Relações Antrópicas, Meio Ambiente e Parasitologia / Mestre em Biologia Animal
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