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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Modelový výzkum účinnosti separačních technologií úpravy vody / The efficiency of water treatment separation processes – model research

Vašalovská, Petra January 2012 (has links)
Goal of this research was to recognize dissolved air flotation efficiency by the help of turbidity and UV absorbance removal for different conditions. As different conditions are meant the efficiency for different baffle position, different detention time in separation zone and checking results with adding chemicals compared to results without adding chemicals.
42

Investigation of biochemical methane potential in Thái Nguyên city and Sông Công city in Vietnam

Deo, Anurag, Axelsson Bjerg, Mette January 2017 (has links)
Currently Vietnam is facing several problems with waste handling. For instance, a lot of the municipal organic solid waste is dumped at landfills, which contributes to environmental difficulties such as greenhouse gas emissions. Anaerobic digestion has proven to be an adequate method for solving environmental problems such as waste treatment, where biogas can be produced. The methane content in the biogas can subsequently be used as a prosperous energy source for heating, electricity and vehicle fuel. The production and utilization of biogas in Vietnam is in a developing face. However, there are issues that should be tackled to improve and expand the biogas production and use. In Vietnam the main substrate used for anaerobic digestion is animal manure as most of the biogas digesters are placed on farms. The purpose of this master thesis was to identify additional potential substrates for biogas production, with focus on Thái Nguyên city and Sông Công city in the Thái Nguyên province. In order to find suitable substrates, interviews and literature research were carried out in Vietnam. Subsequently biochemical methane potential (BMP) tests were performed for the identified and acquired substrates. The BMP-tests were first performed at Thái Nguyên University but as the results were inconclusive, further experiments were performed at Linköping University (Sweden) where eight substrates from the Thái Nguyên province were investigated. The identified substrates used for the BMP-tests were three types of beer waste from the Vicoba brewery in Thái Nguyên city, food waste from different restaurants in Sông Công city, fruit waste from the fruit market in Thái Nguyên and household vegetable waste. The highest methane yield could be observed for household vegetable waste (543 Nml/g VS) followed by beer waste (yeast) with a methane potential of 497 Nml/g VS. Beer waste (hops boiling) had the lowest methane potential with a value of 230 Nml/g VS. Estimation of the total methane potential in both cities together from food waste from restaurants, beer waste and sewage sludge from the upcoming waste water treatment plant (WWTP) in Thái Nguyen city were made by combining data from interviews, literature values and the BMP-results. The estimation showed that from Thái Nguyên City and Sông Công city about 137,500 m3 CH4/year can be produced from food waste from restaurants, about 1.7 millionCH4 m3/year can be produced from sludge from the WWTP in Thái Nguyên city (under construction) and there is also a possibility to produce about 10,700 m3 CH4/year from the beer brewery in Thái Nguyên city. Thus, the total estimated methane potential sums up to 1.8 million m3 CH4/year. The results show that Thái Nguyên city and Sông Công city have potential wastes that preferably could be used as substrates for biogas production which could add on to the biogas produced currently at farm level in the Thái Nguyên region. / I dagsläget står Vietnam inför svåra problem med rådande avfallshantering. En stor del av det organiska avfallet deponeras. Detta bidrar till miljöproblem som exempelvis utsläpp av växthusgaser. Kontrollerad rötning har visat sig vara en bra metod för avfallshantering av organiskt avfall, eftersom biogasen som produceras exempelvis kan användas som energikälla för matlagning, elektricitet och fordonsbränsle, samtidigt som avfallsmängden kraftigt reduceras. Utvecklingen av kommersiell biogasproduktion i Vietnam är fortfarande i ett inledande stadie. De främsta substraten för biogassubstratet som används i landet i nuläget är olika typer av gödsel med anledning av att de flesta rötkammare är placerade på bondgårdar. Syftet med denna studie är att undersöka kompletterande potentiella substrat som kan användas för biogasproduktion i städerna Thái Nguyên och Sông Công som är belägna i provinsen Thái Nguyên. För att identifiera möjliga biogassubstrat genomfördes intervjuer på plats tillsammans med litteraturundersökningar. Vidare genomfördes metanpotentialbestämningar (BMP) för identifierade, utvalda och, erhållna substrat. Det visade sig ej vara möjligt inom tidsramen för besöket att genomföra BMP-testerna på ett fullgott sätt vid Thái Nguyêns universitet med anledning av begränsningar i metodförutsättningar, varför BMP-tester även genomfördes på Linköpings universitet. Totalt testades metanpotentialen för åtta olika substrat från städerna Thái Nguyên och Sông Công. De identifierade substraten som användes i BMP-studien var tre typer av bryggeriavfall från Vicoba bryggeri i Thái Nguyên, matavfall från olika restauranger i Sông Công, fruktavfall från fruktmarknaden i Thái Nguyên och hushållsavfall från ett hushåll i Thái Nguyên. Det högsta metanutbytet kunde observeras för matavfall från hushåll (543 Nml/g VS) följt av bryggeriavfall i form av jäst (497 Nml/g VS). Ölavfall från vörtkokning påvisade det lägsta metanutbytet av samtliga testade substrat motsvarande 230 Nml/g VS. En uppskattning av den totala metanpotentialen i de båda städerna från matavfall från restauranger, bryggeriavfall samt avloppsslam från reningsverket som är under uppbyggnad i Thái Nguyên genomfördes baserat på intervjuer, litteraturvärden samt genomförda metanpotentialtester (BMP). Uppskattningen visade att cirka 137 500 m3 CH4/år skulle kunna produceras från matavfall från restauranger, cirka 1,7 miljoner CH4 m3/år från avloppsreningsverksslam samt från ölbryggeriet i Thái Nguyên är det möjligt att producera cirka 10 700 CH4 m3/år. Sammantaget indikerar det en uppskattad metanpotential motsvarande ca 1,8 miljoner CH4 m3/år. Slutsatsen av den här studien visar att det finns stor potential för biogasproduktion i Thái Nguyên och Sông Công. / Developing strategies and methods for participatory planning in Thái Nguyên and Linköping
43

ANÁLISE QUÍMICA MULTIELEMENTAR DE AMOSTRAS DE ÁGUA TRATADA EM 18 MUNICÍPIOS DO NORTE GOIANO

Silva, Queren Haamonai Santos da 21 March 2013 (has links)
Made available in DSpace on 2016-08-10T10:53:48Z (GMT). No. of bitstreams: 1 QUEREN HAAMONAI SANTOS DA SILVA.pdf: 1839585 bytes, checksum: e87373a19afc13fac0e6123bdb351583 (MD5) Previous issue date: 2013-03-21 / This study analyzed the quality of the water consumed by the population of the 18 municipalities that make up the northern region of the state of Goiás, Brazil. Chemical analyzes were performed multielement (ICP-OES method) of the material collected in the Water Treatment Plants (WTP). From the results, we constructed a correlation matrix defining the geochemical associations. The analysis of integrated data revealed the presence of high concentrations (1 st, 2 nd and 3 rd order) of chemical elements and chemical compounds, respectively, Ba, Ca, Cl, Fe, Mg, Mn, Sr, Zn, SO4 and NO3. Visits were carried out in the cities studied ETAs, to check the type of water treatment, and evaluate possible environmental exposure. We stress the importance of this study as multielement disclosure about the quality of drinking water in the state of Goiás, emphasizing the multistakeholder nature of government agencies, civil society, in order to guide policy strategies to promote the quality of drinking water, as well as the preservation of water sources. / O presente trabalho analisou-se a qualidade da água consumida pela população dos 18 municípios que compõem a região norte do Estado de Goiás, Brasil. O objetivo atingido foi a classificação dos elementos químicos segundo a ordem de significância e o seu potencial de toxicidade. Pelas análises químicas multielementares (método ICP- OES) do material coletado nas Estações de Tratamento de Água (ETAs). A partir dos resultados, foi construída uma matriz de correlação definindo as associações geoquímicas. A analise integrada dos dados revelou a presença de altas concentrações (1º, 2º e 3º ordem) dos elementos químicos e compostos químicos, respectivamente, Ba, Ca, Cl, Fe, Mg, Mn, Sr, Zn, SO4 e NO3. Foram realizadas visitas nas ETAs dos municípios estudados, para verificação do tipo de tratamento da água, e avaliar uma possível exposição ambiental. Ressalta-se a importância deste estudo como divulgação sobre a qualidade multielementar da água potável, no Estado de Goiás, enfatizando o caráter multiparticipativo de órgãos governamentais, sociedade civil, de modo a orientar as estratégias políticas a fim de promover a qualidade da água potável, assim como a preservação dos mananciais.
44

Modelo conceitual de seleção de tecnologias de tratamento de água para abastecimento de comunidades de pequeno porte / Conceptual selection model of technologies of water treatment for the supply of small communities

Sabogal Paz, Lyda Patricia 28 September 2007 (has links)
Os investimentos no setor de água potável no Brasil, apesar de significativos, ainda não apresentam os resultados esperados na melhoria da saúde e da qualidade de vida da população, especialmente nas pequenas comunidades do país. A aplicação de recursos continuará limitada enquanto não forem fortalecidos os aspectos técnicos, econômicos, institucionais, ambientais, sociais e culturais que permitam a seleção de obras sanitárias eficientes e sustentáveis. Neste contexto, foi desenvolvido um modelo conceitual de seleção de tecnologias de tratamento de água constituído por 17 sub-níveis que progressivamente \"filtram\" as opções tecnológicas aplicáveis em comunidades brasileiras inferiores a 20.000 habitantes. Os aspectos envolvidos no modelo se relacionam: i) ao risco presente na fonte de abastecimento superficial; ii) à eficiência das tecnologias para eliminar ou reduzir o risco a valores de acordo à Portaria no 518 (2004); iii) ao tratamento, aproveitamento e disposição dos resíduos gerados e iv) aos custos dos sistemas com vazões de projeto de 10 a 40 L/s. As principais conclusões da pesquisa foram: i) a aplicabilidade do modelo está restrita à estações de tratamento de água - ETAs que cumprem todos seus requisitos de domínio, ii) os valores-limite das variáveis de risco podem conduzir o engenheiro a uma seleção preliminar das possíveis alternativas de tratamento; entretanto, somente a partir de estudos de tratabilidade da água e de testes em instalação piloto será possível definir a ETA mais conveniente, iii) as seleções das tecnologias para tratamento, aproveitamento e disposição do resíduo não devem ser avaliadas de forma independente às empregadas nas ETA; iv) Os custos calculados pelo modelo dificilmente podem ser comparados com sistemas já existentes; v) os resultados do modelo variam em função dos dados de entrada; assim, o usuário deve ter consciência da qualidade da informação fornecida para obter resultados satisfatórios. / Despite being significant the investments in the brazilian drinking water sector still have not presented the expected results regarding the improvement of both health and population\'s life quality, especially in the small communities of the country. The application of resources will continue limited while the technical, economical, institutional, environmental, social and cultural aspects that allow for the selection of efficient and maintainable sanitary works are not strengthened. In this context, a conceptual model to select technologies for water treatment has been developed. It consists of 17 sub-levels that progressively \"filter\" the applicable technological options in brazilian communities of under 20.000 inhabitants. The aspects involved are related to: i) the risk present in the source of superficial supply; ii) the efficiency of the technologies to lither eliminate or reduce the risk to the values according law no 518 (2004); iii) the treatment, use and disposition of the generated residues and iv) the costs of the systems with project flows from 10 L/s to 40L/s. The main conclusions of the research were: i) the applicability of the model is restricted to water treatment plants - WTPs that accomplish all their domain requirements, ii) the limit values of the risk variables can lead the engineer to a preliminary selection of the possible treatment alternatives; however, only from studies of water treatment and tests in pilot installations it will be possible to define the most convenient WTP, iii) the selections of the technologies for treatment, use and disposition of residues should not be appraised in an independent way of the ones employed in WTPs, iv) the costs calculated by the model can hardly be compared with systems already existent; v) the results of the model vary in function of the input data; therefore, the user should be aware of the quality of the information supplied to obtain satisfactory results.
45

Kauno nuotėkų tinklų panaudojimas elektros energijos gamybai / Use Kaunas Waste Water Network For Electric Power Generation

Papievis, Juozas 03 June 2009 (has links)
Visų hidroelektrinių veikimo principas pagrįstas dviem pagrindiniais parametrais, - slėgio aukščiu ir debitais. Lietuvoje iki 2009 metų buvo pastatyta 82 MHE. Šis etapas jau baigiasi, kadangi potencialių vietų mažajai hidroenergetikai plėtoti Lietuvoje beveik neliko ir buvo paskelbtos upės, kuriose draudžiama statyti užtvankas. Šiame tyrime buvo ieškoma alternatyvaus, netradicinio sprendimo – vandentiekos ir vandenvalos tinklų panaudojimui. Tyrimų tikslas – išnagrinėti Kauno nuotėkų tinklų galimybes elektros energijos gamybai. Buvo apžvelgtos galimybės Pabaltijo šalyse panašaus tipo projektams įgyvendinti. Taip pat buvo apžvelgtos Kauno nuotėkos ir ištirta galimybė panaudoti esamą infrastruktūrą elektros energijos gamybai Kauno nuotėkų pirmose ir antrose valymo grotose. Šiame darbe pateikiama metodika, leidžianti apskaičiuoti projektinius hidrografus programa SMADA kurią naudoja JAV universiteto studentai projektuojantys užtvankas, krantines ir kitką. Vadovaujantis sudarytais hidrografais, pasirenkama turbina ir apskaičiuojamas jos galingumas bei komponavimo tipas programa RETScrean. RETScrean sukurta Kanadoje. Ji skirta įvertinti atnaujinamų energijos technologijų projektus. Skaičiuojant šia programa, buvo pasirinkti vidutinio 50 % tikimybės vandeningumo metai. Žinant tai buvo apskaičiuoti instaliuotas galingumas, metinis išdirbis ir turbinos tipas. Vertinant turbinų komponavimo tipus, buvo atliekama daugiakriterinė analizė programine įranga DAM ir pasirinktas optimaliausias... [toliau žr. visą tekstą] / The way of working of all hydroelectric power stations is based on two main parameters: the pressure height and the rate. 82 SHP were built in Kaunas till 2009. This period is coming to the end since there are not many places left for the Small Hydropower development in Lithuania. In addition to this, the list of rivers was announced in which it is forbidden to build dams. Therefore, the untraditional way of producing the electric power in the waste water network was explored. The aim of this research is to analyze the possibilities of Kaunas Waste Water Network for the Electric Power Generation. The opportunities to realize similar types of projects in the Baltic States as well as to adapt them to the existing infrastructure in primary and secondary wastewater grating of Kaunas were discussed in this research. Methodology that is presented in this paper enables to calculate hydrographs by the use of SMADA which influences the choice of the turbine and calculations of its power as well as the type of composition by the use of RETScrean. SMADA is widely used by the students of universities in the USA. The program RETScrean, that is used to evaluate the renewed projects of energetic technologies, was created in Canada. The year with the probability 50 % of wateriness was chosen. This information was used to calculate the installed powerfulness, production per year as well as the type of the turbine with a programme RETScrean. Multicriteria analysis was performed by the use of... [to full text]
46

The characterisation of some South African water treatment residues and glasshouse pot experiments to investigate the potential of two residues for land disposal.

Titshall, Louis William. January 2003 (has links)
Water treatment residues (WTRs) are the by-product from the production of potable water. They consist mainly of the precipitated hydrous oxides of the treatment chemicals, and materials removed from the raw water. This study investigated the range of treatment processes and residues produced in South Africa, and two WTRs were selected for testing on selected soils and mine materials. A questionnaire was developed and sent to water treatment authorities across South Africa. Information on the treatment chemicals, dosages, volumes and current disposal practices, and a sample of WTR from each treatment plant were requested. Eleven, of 21 authorities, returned completed questionnaires, representing 37 water treatment facilities. Organic polymers were the most commonly used treatment chemical, with most plants also using lime. Other less frequently used chemicals and additives were Alz(S04)3.14I-hO, Fe2(S04)3, FeC!), sodium aluminate, activated silica, activated charcoal, CO2 and bentonite. Information given regarding residue thickening and disposal was poor. Samples from Rand Water, Umgeni Water (Midmar), Midvaal Water Company, Amatola Water and Cape Metropolitan Council (Faure) were received or collected. An additional sample from Faure was also received, representing a change in the treatment process. These samples were analysed for a range of chemical and physical characteristics. These analyses showed that the WTRs had the potential to supply some plant nutrients (Ca, Mg, Fe, S) but that metal toxicity may be a problem, in particular Mn in the Faure WTR, and that P adsorption may be severe. The samples selected to test the potential for land disposal were from Rand Water and Faure. A pot experiment tested the growth of Eragrostis tefJ, Cenchrus ciliaris and Digitaria eriantha in mixtures of Rand WTR and material from a coal mine i.e., a sandy soil material, spoil material and coal combustion ash, at rates of 0, 50, 100, 200 and 400 g kg" with a uniform fertiliser treatment applied to all mixtures. The grass was harvested on three occasions and the mean total yield (dry mass) determined, as well as nutrient uptake. The pots were leached after each harvest and the pH and electrical conductivity determined. The soil, spoil and ash were characterised and pH, EC and water retention characteristics of the mixtures determined. Growth of the grasses in the ash treatments was poor and these were terminated. Eragrostis tefJ grown in the soil showed a decrease in mean total yield with increasing WTR application rate, but yield was good up to the 200 g kg" treatment at the first harvest, declining substantially by the second harvest. In general C. ciliaris and D. eriantha grown in the soil showed a decrease in mean total yield for all harvests with increasing WTR application. The yield of E. /ejJ, grown in the spoil, increased up to 100 g kg,l WTR addition, but decreased thereafter. Digitaria eriantha showed a decrease in yield, and C. ciliaris an increase, with increasing WTR application rate , but for all treatments the differences were non-significant. The pH and EC of the leachates generally increased with increasing WTR addition. The concentration of nutrients in the grasses did not indicate any deficiencies or toxicities. As the growth of grass was poor in the ash treatments, another pot experiment was established to test the growth of two creeping grass species grown in the Rand WTR as a cover over the ash material. Cynodon dactylon and Stenotaphrum secundatum were grown in 20, 40 and 60 mm layers of Rand WTR, with and without a fertiliser treatment. Both species performed best in the 60 mm layer with fertiliser, and C. dactylon performed better than S. secundatum. The former species was more tolerant of the high pH, but both have potential as cover vegetation on the ash dumps when these are covered with Rand WTR. A further glasshouse study investigated the effect of Faure WTR mixed with a nutrient poor sandy soil on the nutrient uptake and seed yield of common dry beans (Phaseolus vulgaris). The WTR was added to the soil at 0, 50, 100, 200 and 400 g kg" each with five levels of fertiliser (0, 25, 50, 100 (recommended optimum) and 150 %). Bean pods were harvested once the plants had senesced. The number of pods and mass and number of seeds per treatment were determined. The seeds were analysed for nutrient uptake. Interveinal chlorosis and necrotic lesions were evident on cotylendonous and new leaves in the WTR treated soils, the severity of the symptoms increasing with increasing rate of WTR. Additional pots were established at the 400 g kg" rate (without fertiliser) and leaf material collected for chemical analysis. This showed that Mn toxicity was the cause, with leaf concentrations about 12 times the recommended 100 mg kg" upper limit. However, mass of bean seed was highest in the 400 g kg" Faure WTR treatment with 150 % fertiliser. Nutrient translocation to the seed seemed to be relatively consistent regardless of treatment, with little accumulation ofMn. The data collected illustrated the range of conditions and types of WTRs produced in South Africa, and that in some instances these residues have favourable characteristics for land application. The use of the Rand WTR showed that it could be applied to the spoil medium at relatively high concentrations without severely negatively impacting on grass growth, but more caution should be used when applying this material to the soil medium. While the grass did not grow in the ash treatments, it would seem that with suitable species the Rand WTR could be beneficially applied to ash material as a cover layer. The use of the Faure WTR on a sandy soil seemed to potentially improve the yield of the indicator crop, but caution should be exercised due to the possibility of Mn toxicity. The use of additional fertiliser would seem to be essential. Further research would require that field scale investigation of both WTRs be conducted, as well as further studies of applicat ion rates and techniques in laboratory and glasshouse investigations. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.
47

The characterisation of some South African water treatment residues and glasshouse pot experiments to investigate the potential of two residues for land disposal.

Titshall, Louis William. January 2003 (has links)
Water treatment residues (WTRs) are the by-product from the production of potable water. They consist mainly of the precipitated hydrous oxides of the treatment chemicals, and materials removed from the raw water. This study investigated the range of treatment processes and residues produced in South Africa, and two WTRs were selected for testing on selected soils and mine materials. A questionnaire was developed and sent to water treatment authorities across South Africa. Information on the treatment chemicals, dosages, volumes and current disposal practices, and a sample of WTR from each treatment plant were requested. Eleven, of 21 authorities, returned completed questionnaires, representing 37 water treatment facilities. Organic polymers were the most commonly used treatment chemical, with most plants also using lime. Other less frequently used chemicals and additives were A12(SO4)3.14H2O, Fe2(SO4)3, FeC1), sodium aluminate, activated silica, activated charcoal, CO2 and bentonite. Information given regarding residue thickening and disposal was poor. Samples from Rand Water, Umgeni Water (Midmar), Midvaal Water Company, Amatola Water and Cape Metropolitan Council (Faure) were received or collected. An additional sample from Faure was also received, representing a change in the treatment process. These samples were analysed for a range of chemical and physical characteristics. These analyses showed that the WTRs had the potential to supply some plant nutrients (Ca, Mg, Fe, S) but that metal toxicity may be a problem, in particular Mn in the Faure WTR, and that P adsorption may be severe. The samples selected to test the potential for land disposal were from Rand Water and Faure. A pot experiment tested the growth of Eragrostis teff, Cenchrus ciliaris and Digitaria eriantha in mixtures of Rand WTR and material from a coal mine i.e., a sandy soil material, spoil material and coal combustion ash, at rates of 0, 50, 100, 200 and 400 g kg-1 with a uniform fertiliser treatment applied to all mixtures. The grass was harvested on three occasions and the mean total yield (dry mass) determined, as well as nutrient uptake. The pots were leached after each harvest and the pH and electrical conductivity determined. The soil, spoil and ash were characterised and pH, EC and water retention characteristics of the mixtures determined. Growth of the grasses in the ash treatments was poor and these were terminated. Eragrostis teff grown in the soil showed a decrease in mean total yield with increasing WTR application rate, but yield was good up to the 200 g kg-1 treatment at the first harvest, declining substantially by the second harvest. In general C. ciliaris and D. eriantha grown in the soil showed a decrease in mean total yield for all harvests with increasing WTR application. The yield of E. teff, grown in the spoil, increased up to 100 g kg-1 WTR addition, but decreased thereafter. Digitaria eriantha showed a decrease in yield, and C.ciliaris an increase, with increasing WTR application rate, but for all treatments the differences were non-significant. The pH and EC of the leachates generally increased with increasing WTR addition. The concentration of nutrients in the grasses did not indicate any deficiencies or toxicities. As the growth of grass was poor in the ash treatments, another pot experiment was established to test the growth of two creeping grass species grown in the Rand WTR as a cover over the ash material. Cynodon dactylon and Stenotaphrum secundatum were grown in 20, 40 and 60 mm layers of Rand WTR, with and without a fertiliser treatment. Both species performed best in the 60 mm layer with fertiliser, and C. dactylon performed better than S. secundatum. The former species was more tolerant of the high pH, but both have potential as cover vegetation on the ash dumps when these are covered with Rand WTR. A further glasshouse study investigated the effect of Faure WTR mixed with a nutrient poor sandy soil on the nutrient uptake and seed yield of common dry beans (Phaseolus vulgaris). The WTR was added to the soil at 0, 50, 100, 200 and 400 g kg-1 each with five levels of fertiliser (0, 25, 50, 100 (recommended optimum) and 150 %). Bean pods were harvested once the plants had senesced. The number of pods and mass and number of seeds per treatment were determined. The seeds were analysed for nutrient uptake. Interveinal chlorosis and necrotic lesions were evident on cotylendonous and new leaves in the WTR treated soils, the severity of the symptoms increasing with increasing rate of WTR. Additional pots were established at the 400 g kg-1 rate (without fertiliser) and leaf material collected for chemical analysis. This showed that Mn toxicity was the cause, with leaf concentrations about 12 times the recommended 100 mg kg-1 upper limit. However, mass of bean seed was highest in the 400 g kg-1 Faure WTR treatment with 150 % fertiliser. Nutrient translocation to the seed seemed to be relatively consistent regardless of treatment, with little accumulation of Mn. The data collected illustrated the range of conditions and types of WTRs produced in South Africa, and that in some instances these residues have favourable characteristics for land application. The use of the Rand WTR showed that it could be applied to the spoil medium at relatively high concentrations without severely negatively impacting on grass growth, but that more caution should be used when applying this material to the soil medium. While the grass did not grow in the ash treatments, it would seem that with suitable species the Rand WTR could be beneficially applied to ash material as a cover layer. The use of the Faure WTR on a sandy soil seemed to potentially improve the yield of the indicator crop, but caution should be exercised due to the possibility of Mn toxicity. The use of additional fertiliser would seem to be essential. Further research would require that field scale investigation of both WTRs be conducted, as well as further studies of application rates and techniques in laboratory and glasshouse investigations. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.
48

Διερεύνηση της συμπεριφοράς μακροθρεπτικών και βαρέων μετάλλων στο σπανάκι με την επαναχρησιμοποίηση της ιλύος του βιολογικού καθαρισμού Καλαμάτας

Σωτηρόπουλος, Σταύρος 28 February 2013 (has links)
Στην παρούσα μεταπτυχιακή εργασία παρουσιάζονται τα αποτελέσματα της διερεύνησης της επίδρασης της ιλύος βιολογικού καθαρισμού Καλαμάτας (Β.Κ.Κ.) στην ανάπτυξη του σπανακιού (Spinacia Oleracea) καθώς και στην απαορρόφηση N, P, K, Ca, Mg, ιχοστοιχείων Fe, Mn, Cu, Zn, βαρέων μετάλλων Pb, Ni, Cd και Cο από τα διάφορα μέρη του φυτού. Επιπλέον, η εργασία αυτή αποτελεί μια μελέτη της επίδρασης της συγκεκριμένης ιλύος και σε ορισμένους δείκτες ποιότητας των μιγμάτων ιλύος-εδάφους, όπως pH, αλατότητα, οργανική ουσία, ολικό ανθρακικό ασβέστιο, αλλά και σε ποσοτικούς δείκτες όπως η περιεκτικότητα σε ολικό άζωτο (Ν%), διαθέσιμο φωσφόρο (Ρ κατά Olsen), ανταλλάξιμα κατιόντα K, Ca, Mg, και συγκέντρωση ολικών, διαθέσιμων και ανταλλάξιμων ιχνοστοιχείων Fe, Mn, Cu, Zn, "βαρέων μετάλλων" Pb, Ni, Cd, Cr, Co. Τα αποτελέσματα προέρχονται μετά από πειραματική μελέτη που έγινε σε φυτά σπανακιού, αναπτυσσόμενα σε υποστρώματα που προέκυψαν από ανάμιξη εδάφους και ιλύος σε διάφορες αναλογίες, σε υπαίθριο προστατευμένο χώρο. Σκοπός της πειραματικής αυτής μελέτης είναι να ελεγχθούν και να αξιολογηθούν οι ιδιότητες που αποκτούν τα υπό εξέταση υποστρώματα από την προσθήκη ιλύος στο έδαφος ταυτόχρονα με την επίδραση στην ανάπτυξη του σπανακιού. Έτσι σε αδρές γραμμές μπορούμε να συμπεράνουμε ότι τα αποτελέσματα και η αξιολόγησή τους κατατείνουν στο ότι η ιλύς της μονάδας βιολογικού καθαρισμού της Καλαμάτας μπορεί να αξιοποιηθεί ως λίπασμα σε μικρές αναλογίες ιλύος/εδάφους και φαίνεται ότι η διάθεσή της στο έδαφος για γεωργικούς σκοπούς αποτελεί μια πολύ καλή μέθοδο διάθεσης, που πρέπει να εξετάζεται κατά προτεραιότητα. Ταυτόχρονα, επιβάλλεται η συνέχιση και επέκταση της σχετικής έρευνας, για αξιοποίηση και οικολογική διαχείριση της εν λόγω ιλύος. / This study investigates the effects of the sewage sludge of Kalamata Waste Water Treatment Plant (WWTP) both in the development of spinach (Spinacia oleracea) and the absorption of N, P, K, Ca, Mg, Fe, Mn, Cu, Zn, Pb, Ni, Cd and Co from various spinach plant parts. Parameters of soil - sludge mixtures are also considered during this study. Especially the effect of sludge on parameters such as pH, salinity, organic matter, total CaCO3, total nitrogen content (N%), available phosphorus, exchangeable K, Ca, Mg, and concentration of total, available and exchangeable Fe, Mn, Cu, Zn, Pb, Ni, Cd, Cr, Co. The experiments where conducted in Messinia and the results showed that sludge improves soil fertility. The application of sludge does not cause environmental problems in small proportions of sludge – soil mixture. In large quantities the addition of sludge is associated with potential toxicities and increased salinity in the soil as well as potential environmental problems from over-concentration of phosphorus but also heavy metals such as Pb, Ni and Cr. Special attention is need for Cd, not because of high concentration, but because of the special mobility it presents. Finally this study confirms the presence of a large number of interactions between nutrients, heavy metals and soil properties in soil and spinach. The evaluation of these interactions are of great importance because they help us to quantify elemental contribution of soil and plants, helps in understanding the problems of nutrition in preventing the occurrence of toxic problems at the expense of consumer health, the environment and ultimately to effective use of sludge. Finally, the sludge of Kalamata WWTP can be used as fertilizer in small proportions of sludge / soil mixtures and it seems that the disposal of sludge in soils for agricultural purposes is a very good method of disposal that must be considered.
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CARBONATAÇÃO ACELERADA EM CONCRETOS COM ADIÇÃO DE CINZAS DE LODO DE ESTAÇÃO DE TRATAMENTO DE ÁGUA / ACCELERATED CARBONATION IN CONCRETE WITH ADDITION OF WATER TREATMENT PLANT SLUDGE ASHES

Adorna, Diego da Luz 14 July 2016 (has links)
Carbonation is a natural phenomenon for concrete structures and occurs due to the reaction between CO2, which is concentrated in the environment, and Ca(OH)2, which is present in the cementitious matrix. Carbonation reaction reduces the pH of the concrete and causes the destruction of the passivation layer, which surrounds the steel armor, leaving it vulnerable to the process of corrosion. In this study, was investigated the performance against the carbonation of concrete with the addition of water treatment plant sludge ashes, in concentrations of 5%, 10%, 15%, 20%, 25% and 30% replacing Portland cement, as well as a reference blend without mineral admixtures. All mixtures were molded with three w/b ratios (0.35; 0.50 and 0.65) and with two periods of wet cure (three and seven days). Concrete specimens underwent preconditioning according to RILEM TC 116-PCD, targeting the moisture balance (75% ± 2%) in an aerial environment with constant temperature (23° C ± 2° C) and uniform moisture distribution. Afterwards, specimens were forwarded to a carbonation chamber, with humidity (75 ± 2%), temperature (23°C ± 2° C) and CO2 concentration (3%) duly regulated. Specimens were tested after 4, 8, 12 and 16 weeks of CO2 exposure through phenolphthalein spraying, the depths of carbonation is obtained and, therefore, the carbonation coefficients. Results revealed that the incorporation of water treatment plant sludge ashes into concrete leads to increases in its carbonation, in all mixtures investigated. Comparisons with the results for Porosimetry by Mercury Intrusion and Thermogravimetry enable attribute this effect to the microstructural change and decrease of alkalinity of the mixture with addition of sludge ash. Through an analysis of equal resistance, it was found that concrete with addition of sludge ash water treatment are feasible, from the point of view of carbonation's lifespan, only to higher strength levels. / A carbonatação é um fenômeno natural às estruturas de concreto, ocorrendo pela reação entre o CO2, concentrado no ambiente, e o Ca(OH)2, presente na matriz cimentícea. A reação de carbonatação provoca a redução do pH do concreto, causando a destruição da camada passivadora, que envolve a armadura de aço, deixando esta vulnerável ao processo de corrosão. Nesta pesquisa, foi investigado o desempenho, frente à carbonatação, de concretos com adição de cinzas de lodo de estação de tratamento de água, nos teores de 5%, 10%, 15%, 20%, 25% e 30% em substituição ao cimento Portland, bem como uma mistura de referência, sem adições minerais. Todas as misturas foram moldadas com três relações a/agl (0,35; 0,50 e 0,65) e com dois períodos de cura úmida (três e sete dias). Os corpos-de-prova de concreto foram submetidos à um pré-condicionamento, conforme procedimentos sugeridos pela norma RILEM TC 116-PCD, visando o equilíbrio de umidade (75% ± 2%) em um ambiente aéreo com temperatura constante (23°C ± 2°C) e distribuição uniforme de umidade. Posteriormente os corpos-de-prova foram encaminhados para uma câmara de carbonatação, com umidade (75% ± 2%), temperatura (23°C ± 2°C) e concentração de CO2 (3%) devidamente reguladas. Os corpos-de-prova foram ensaiados após 4, 8, 12 e 16 semanas de exposição ao CO2, por meio de aspersão de fenolftaleína, sendo obtidas as profundidades de carbonatação e, com isso, os coeficientes de carbonatação. Os resultados demonstraram que a incorporação de cinzas de lodo de estação de tratamento de água ao concreto acarreta no aumento da carbonatação nos mesmos, para todas as misturas investigadas. Comparações com resultados de Porosimetria por Intrusão de Mercúrio e Termogravimetria permitiram atribuir este efeito às alterações microestruturais e a diminuição da reserva alcalina das misturas com adição de cinzas de lodo. Através de uma análise em igualdade de resistência, constatou-se que os concretos com adição de cinzas de lodo de estação de tratamento de água são viáveis, do ponto de vista da vida útil frente à carbonatação, apenas para níveis de resistência mecânica mais altos.
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Gestão de resíduo e tecnologia ambiental na fabricação de tijolos solo-cimento

Samson, Bárbara pereira 28 April 2016 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2017-07-14T12:50:22Z No. of bitstreams: 1 arquivototal.pdf: 8841136 bytes, checksum: aaa642f094b0481f15236b39854feb0a (MD5) / Made available in DSpace on 2017-07-14T12:50:22Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 8841136 bytes, checksum: aaa642f094b0481f15236b39854feb0a (MD5) Previous issue date: 2016-04-28 / Currently we have been sought new constructive solutions involving environmental sustainability through the reduction / elimination of waste of raw materials and final products. The reduction of waste has been granted by the rational use of materials and various forms of reuse, for both are studied and developed technologies capable of absorbing this waste. Under the basic sanitation is highlighted waste generated in water treatment plants during the process of purifying plants of water intended for human consumption. This residue is commonly called sludge. For environmental issues, frequent studies point to the incorporation of this waste in construction materials such as conventional bricks and soil cement. Laboratory analyzes were: Fluorescence Xray (XRF) , Chemical Oxygen Demand (COD) , Biochemical Oxygen Demand (BOD), Particle size , Plasticity Index and resistance to simple compression. This the following study aims to evaluate the incorporation of the waste generated in the Water Treatment Plant - Gramame in soil-cement bricks type. The concreteness of research leads to consideration of the incorporation of the waste generated in the Water Treatment Plant - Gramame in low percentages do not affect the strength of soil-cement bricks. This result associated with a considerable concentration of Organic matter. / Atualmente têm-se buscado novas soluções construtivas que envolvam a sustentabilidade ambiental através da diminuição/eliminação de desperdício das matérias-primas e produtos finais. A redução dos desperdícios vem sendo conferida pelo uso racional dos materiais e as diversas formas de reutilização, para tanto são estudadas e desenvolvidas tecnologias capazes de absorver estes resíduos. No âmbito do saneamento básico é destacado o resíduo gerado nas Estações de Tratamento de Água durante o processo de potabilização das águas destinadas para o consumo humano. Comumente este resíduo é chamado de lodo. Para as questões ambientais, estudos frequentes apontam para a incorporação deste resíduo em materiais de construção civil tais como tijolos convencionais e solo-cimento. Desta forma, o seguinte trabalho visa avaliar a incorporação do resíduo gerado na Estação de Tratamento de Água – Gramame em tijolos do tipo solo-cimento. Para que os objetivos pudessem ser alcançados foram determinadas as análises laboratoriais de: Fluorescência de Raio-X (FRX), Demanda Química de Oxigênio (DQO), Demanda Bioquímica de Oxigênio (DBO), Granulometria, Índice de Plasticidade e Resistência a Compressão Simples. A concretude da pesquisa leva a conclusão de que a incorporação do resíduo gerado na Estação de Tratamento de Água – Gramame em baixas porcentagens não prejudica a resistência dos tijolos solo-cimento. Sendo este resultado associado a uma considerável concentração de Matéria Orgânica.

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