Made available in DSpace on 2016-08-10T10:47:22Z (GMT). No. of bitstreams: 1 POLLYANNA MARINHO MEDEIROS CEREWUTA.pdf: 1478388 bytes, checksum: 4c568ccbe954787f1615cee835218bba (MD5) Previous issue date: 2014-12-08 / This dissertation analyzes the inclusion of seaweed-like culture agro-energy matrix in the production of biofuels to be used in the State of Goiás, taking into the economic perspective of this undertaking and normative regulation disposed in the Programs of incentive and funding of research of species of microalgae found in the State, due the fact that research developed mainly in the United States confirmed the large lipid productivity of these great carbon dioxide catchers, the gas that simultaneously represented human progress and the atmosphere poisoning, generating numerous problems with undesirable consequences for future generations Starts from the hypotheses of the feasibility of adopting this energy matrix in the productivity of agribusinesses in Goiás, considering the public policy of encouraging and funding at the national and regional level, being a renewable and available resource in the highest degree, so meeting the paradigm provisions in international sustainability standards. Therefore, in the case of biofuels Brazil became the largest consumer of clean energy in the world only because invested for decades and still invests in research, and also intervenes in the economy by regulating the addition and disposal in the consumer market, biofuels prices more attractive than the strictly from fossil fuels. The proposal is to demonstrate that algae-culture is the most efficient energy matrix, although subject to governmental desire to become an alternative to replace fossil fuels about becoming scarce, Due to the increased energy consumption for industrial developments. The methodology to demonstrate this hypothesis comes from the analysis of bibliographic exploratory multidisciplinary branches of biology, chemical engineering, chemistry, developed in Brazil and International about the species that have greater capacity for biomass rich in triglycerides and biotechnology used for this biomass extraction, considering the costs of production, seeing the internal and regional legal standards of ethical guidance to promote sustainability, that before gaining autonomy, depend on state intervention in the market for its insertion. / Esta dissertação analisa a inserção da algacultura como matriz agroenergética na produção de biocombustíveis a ser utilizada no Estado de Goiás, levando em consideração a perspectiva econômica desse empreendimento e a regulação normativa disposta em Programas de incentivo e financiamento de pesquisa de espécies de microalgas encontradas no Estado, devido ao fato de que pesquisas desenvolvidas principalmente nos Estados Unidos da América comprovaram a grande produtividade lipídica dessas grandes captadoras de dióxido de carbono, o gás que ao mesmo tempo representou o progresso humano e o envenenamento do atmosférico, gerando inúmeros problemas indesejáveis que serão arcados pelas gerações futuras. Parte-se da hipótese da viabilidade da adoção dessa matriz energética nas cadeias produtivas do agronegócio goiano, levando em consideração as políticas públicas de incentivo e financiamento em âmbito nacional e regional, por ser um recurso renovável e disponível por excelência, assim atendendo ao paradigma de sustentabilidade disposto nas normas internacionais. Desta forma, em se tratando de biocombustíveis o Brasil só se tornou o maior consumidor de energia limpa do mundo, porque investiu por décadas e ainda investe em pesquisa, e, ainda intervém na economia regulando a adição e a disposição no mercado de consumo, biocombustíveis a preços mais atrativos que os estritamente provenientes de combustíveis fósseis. A proposta consiste em demonstrar que a algacultura é a matriz energética mais eficiente, muito embora dependa da vontade governamental para se tornar uma alternativa à substituição de combustíveis fósseis em vias de tornarem-se escassos, graças ao aumento do consumo de energia pelo desenvolvimentismo industrial. A metodologia para demonstrar essa hipótese vem da análise de pesquisa exploratória bibliográfica multidisciplinar de ramos da biologia, da engenharia química, da química, desenvolvidas no Brasil e no exterior sobre as espécies que possuem maior capacidade de biomassa rica em triglicérides e a biotecnologia utilizada para a extração dessa biomassa, considerando os custos da produção, levando em consideração as normas jurídicas internas e regionais de orientação ética à promoção da sustentabilidade, que antes de ganharem autonomia, dependem da intervenção estatal para sua inserção no mercado.

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The demand for clean and environmentally benign energy resources has been a great concern in the last two decades. To alleviate the associated environmental problems, reduction of the use of fossil fuels by developing more cost-effective renewable energy technologies becomes more and more significant. Among various types of renewable energy sources, solar energy and bioenergy take a great proportion. This dissertation focuses on the heat transfer and flow in solar energy and bioenergy systems, specifically for Thermal Energy Storage (TES) systems in Concentrated Solar Power (CSP) plants and open-channel algal culture raceways for biofuel production. The first part of this dissertation is the discussion about mathematical modeling, numerical simulation and experimental investigation of solar TES system. First of all, in order to accurately and efficiently simulate the conjugate heat transfer between Heat Transfer Fluid (HTF) and filler material in four different solid-fluid TES configurations, formulas of an effective heat transfer coefficient were theoretically developed and presented by extending the validity of Lumped Capacitance Method (LCM) to large Biot number, as well as verifications/validations to this simplified model. Secondly, to provide design guidelines for TES system in CSP plant using Phase Change Materials (PCM), a general storage tank volume sizing strategy and an energy storage startup strategy were proposed using the enthalpy-based 1D transient model. Then experimental investigations were conducted to explore a novel thermal storage material. The thermal storage performances were also compared between this novel storage material and concrete at a temperature range from 400 °C to 500 °C. It is recommended to apply this novel thermal storage material to replace concrete at high operating temperatures in sensible heat TES systems. The second part of this dissertation mainly focuses on the numerical and experimental study of an open-channel algae culture raceway for biofuel production. According to the proposed flow field design of ARID-HV algal raceway, experiments and numerical simulation have been conducted to understand the enhancement of flow mixing in the flow field of ARID-HV raceway by cutting slots on top of the dam near the dead zones. A new method was proposed to quantitatively evaluate the flow mixing by using the statistics of temporal and spatial distribution of the massless fluid particles (centered in each cell at the inlet surface) in the raceway collecting the data of path-lines of fluid particles from CFD results. It is hoped that this method can be applied to assist the algal raceway flow field design as well as other engineering applications. The third part introduces the details about the construction work of a high temperature molten salt test loop. Because of the limited operating temperature of conventional synthetic oils, in order to obtain higher energy conversion efficiency, higher operating temperature is always desirable in a CSP plant which leads to the requirement of new generation of HTF. Currently, a halide salt eutectic mixture (NaCl-KCl-ZnCl₂) as a potential HTF for future CSP applications has been proposed by a multi-institute research team, led by University of Arizona. The thermophysical properties of the halide eutectic salt have been measured. However, this new developed halide eutectic salt has not been tested in a circulating loop at a high operating temperature for the measurement of heat transfer coefficient. It is a significant effort to build such a test system due to extremely high operating temperature. As a consequence, in the third part of this dissertation, details about the design of the lab-scale test system and all the equipment items will be introduced. The investigations included in this dissertation for the heat transfer and flow in solar energy and bioenergy systems are of particular interest to the renewable energy engineering community. It is expected that the proposed methods can provide useful information for engineers and researchers.

Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen (viewed 1/24/2008). Includes bibliographical references.

Microalgae have a variety of commercial applications, the oldest of which include utilisation as a food source and for use in wastewater treatment. These applications, however, are seldom combined due to toxicity concerns, for ethical reasons, and generally the requirement for cultivation of a single algae species for use as a feed supplement. These problems might be negated if a “safer” wastewater such as that from agricultural and/or commercial food production facilities were to be utilised and if a stable algae population can be maintained. In this investigation preliminary studies were carried out using an Integrated Algae Pond System (IAPS) for domestic wastewater treatment to determine the species composition in the associated High Rate Algae Ponds (HRAPs). The effect of different modes of operation, continuous versus batch, on nutrient removal, productivity and species composition was also investigated. Furthermore, indigenous species in the HRAP were isolated and molecularly identified as, Chlorella, Micractinium, Scenedesmus and Pediastrum. Additionally, the effect of the nor amino acid, 2-hydroxy-4-(methylthio)-butanoic acid (HMTBA) and its Cu-chelated derivative, on the growth and biochemical composition of Chlorella, Micractinium, Scenedesmus, Pediastrum and Spirulina was investigated. Species composition in the HRAP was stable under continuous operation with Micractinium dominating > 90% of the algae population. Under batch operation the population dynamic shifted; Chlorella outcompeted Micractinium possibly due to nutrient depletion and selective grazing pressures caused by proliferation of Daphnia. Higher species diversity was observed during batch mode as slower growing algae were able to establish in the HRAP. Nutrient removal efficiency and biomass productivity was higher in continuous mode, however lower nutrient levels were obtained in batch operation. HMTBA did not significantly affect growth rate, however treatment with 10 mg.L-1 resulted in slightly increased growth rate in Micractinium and increased final biomass concentrations in Chlorella, Micractinium and Spirulina (although this was not statistically significant for Micractinium and Spirulina), which are known mixotrophic species. Algae treated with Cu-HMTBA, showed reduced final biomass concentration with 10 mg.L-1, caused by Cu toxicity. Biochemical composition of the algae was species-specific and differed through the growth cycle, with high protein observed during early growth and high carbohydrate during late growth/early stationary phase. Additionally, 0.1 mg.L-1 HMTBA and Cu-HMTBA significantly reduced protein content in Chlorella, Micractinium, Scenedesmus and Pediastrum. In conclusion, operation of the HRAP in continuous culture provided suitable wastewater treatment with high productivity of an ideal species, Micractinium, for use in animal feed supplementation. This species had 40% protein content during growth (higher than the other species tested) and dominated the HRAP at > 90% of the algae population during continuous mode. Addition of HMTBA (> 1 mg.L-1) to algae cultivation systems and those treating wastewater, has the potential to improve productivity and the value of the biomass by enhancing protein content. Overall, the co-utilisation of microalgae for wastewater treatment and the generation of a biomass rich in protein, for incorporation into formulated animal feed supplements, represents a closed ecosystem which conserves nutrients and regenerates a most valuable resource, water.

MESHWR / Department of Hydrology and Water Resources / In South Africa, inland aquaculture is on the increase, especially among the rural communities. Thus aquaculture is able to provide a source of employment and improve rural incomes. This study assessed algae species and their cyanotoxins in small holder production in Vhembe district, Limpopo, South Africa. Thirteen study sites were selected to assess the algae species and their cyanotoxins. The water samples were collected in four quarters and analysed for water temperature, pH, total dissolved solids, Electrical conductivity, phosphates, nitrates, chlorophyll, cyanobacteria, cyanotoxins, metal species and quality of the water in the fish ponds. In the 1st quarter of the year there was variation in Water Temperature (23.7oC-31.4oC), pH (5.5-9.6), EC (3.82-46.8μS/cm), TDS (2.4-45 mg/L), Phosphate (0.0-1.09mgL-1), Nitrates (0.0-1.00mgL-1), Chlorophyll-a (5.8-11.5mg/m-3). In the 2nd quarter there was variation inwater temperature (22.4-25.0oC), pH (6.6-8.8.9), EC (19.23-21.47μS/cm), TDS (12.5-17.9 mg/L), Phosphate (1.64-1.84mgL-1), Nitrates (1.02-1.88mgL-1), Chlorophyll-a (4.6-15.6mg/m-3). In the 3rd quarter there was variation for water temperature (22.9-25.0oC), pH (7.5-9.1), EC (7.91-293.3μS/cm), TDS (11.7-180.9 mg/L), Phosphate (1.10-1.80mgL-1), Nitrates (1.28-1.84mgL-1),Chlorophyll-a (6.8-15.6mg/m-3). In the 4th quarter there was variation forwater temperature (23.5-30.3), pH (7.1-9.3), EC (18.24-623μS/cm), TDS (23.7-136.4 mg/L), Phosphate (1.45-1.99mgL-1), Nitrates (1.43-1.68mgL-1), Chlorophyll-a (6.6-25.9mg/m-3). The metal content of the fish pond water was variable throughout the year but with moderate levels of Al, Cd, Cr, Mn, Fe, Cu, Zn and Ba were found. The metal Fe, exceeded the DWAF guideline values during this first quarter. The presence of Cd in the fish pond water could be attributed to rainfall eroding the earthen embankments of the fish pond. The results of physico-chemical parameters promotes the growth of cyanobacteria in the fish ponds. Flow cam and SEM were used to identify the cyanobacteria species and most cyanobacteria identified are hazard to human health, fish and other aquatic organisms. Molecular technologies were used to identify cyanotoxins and there was no cyanotoxins detected which was concluded that during collection of water samples no cyanobacteria produced toxins. / NRF