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

Obtención de poli(hidroxialcanoato)s empleando vinazas como sustrato

Trapé, Daiana Vanina 31 July 2023 (has links)
Los biopolímeros se presentan como una opción promisoria a los polímeros sintéticos convencionales, ya que son biodegradables y se obtienen de fuentes renovables. Entre ellos, los poli(hidroxialcanoato)s (PHAs) son biopoliésteres especialmente atractivos por su similitud en propiedades finales con algunos de los polímeros sintéticos, pero con la ventaja adicional de ser biodegradables. Sin embargo, el costo de producción de los PHAs es alto debido, principalmente, al costo de la fuente de carbono. Por lo que buscar materias primas más económicas es crucial para reducir los costos asociados a la producción de estos biopoliésteres. El objetivo de esta tesis fue estudiar la producción de PHAs utilizando vinaza (residuo de la industria del bioetanol) como sustrato y Bacillus megaterium como microorganismo productor. En este sentido, se optimizó la composición del medio de cultivo y las condiciones de fermentación mediante un diseño experimental y la metodología de superficie de respuesta, lográndose una productividad de 0,0105 g.L-1.h-1 Mediante optimización matemática se demostró que producir PHAs a partir de vinaza es económicamente viable, especialmente si el microorganismo productor posee una alta capacidad de acumulación del biopolímero, si la vinaza es pretratada o mezclada con otras fuentes de carbono más accesibles y si se agregan sales minerales al medio. Por otra parte, se exploró la obtención de vinaza seca mediante secado por aspersión, empleando maltodextrina como aditivo coadyuvante y se demostró que su uso como sustrato resultó en una mayor productividad de PHAs (0,0227 g.L-1 h-1) en comparación con la vinaza líquida. Este incremento podría atribuirse a la presencia de la maltodextrina que resultaría en una fuente de carbono más accesible en la fermentación empleado como cepa Bacillus megaterium, en concordancia con los resultados del estudio de factibilidad técnico-económica. Los PHAs biosintetizados se sometieron a una caracterización molecular y térmica mediante Espectroscopía Infrarroja con Transformada Fourier (FTIR), Calorimetría Diferencial de Barrido (DSC) y Análisis Termogravimétrico (TGA). Los valores de la temperatura de fusión de los PHAs obtenidos sugieren que el biopolímero podría estar formado por 3HB con comonómeros de cadena mas larga como el 3HV, entre otros. En función de los resultados reportados en la literatura los PHAs obtenidos resentan una temperatura de fusión similar al P(3HB-co-3HV) con una concentración aproximada del 9 mol% HV. Los avances en la optimización de la producción de PHAs utilizando vinaza como sustrato, la evaluación económica, la obtención de vinaza seca y su uso para la síntesis de PHAs y la caracterización de los PHAs permiten avanzar hacia una producción más sostenible de materiales poliméricos biodegradables y renovables. Además, los resultados experimentales obtenidos representan una importante contribución al estudio de la biosíntesis de PHAs empleando procesos biotecnológicos más económicos. / Biopolymers are presented as a promising option to conventional synthetic polymers, since they are biodegradable and they can be obtained from renewable resources. Among them, poly(hydroxyalkanoates)s (PHAs) are especially attractive biopolyesters due to their similarity in final properties to some synthetic polymers, but with the additional advantage of being biodegradable. However, the production cost of PHAs is high, mainly due to the cost of the carbon source. Therefore, looking for more economical raw materials is crucial to reduce the costs associated with the production of these biopolyesters. This thesis focused on studying the production of PHAs using vinasse (residue from the bioethanol industry) as substrate and Bacillus megaterium as the producing microorganism. In this sense, the composition of the culture medium and fermentation conditions were optimized through an experimental design and the response surface methodology, achieving a productivity of 0.0105 g.L-1.h-1. Through mathematical optimization, it was shown that producing PHAs from vinasse is economically viable, especially if the producing microorganism has a high capacity for biopolymer accumulation, if the vinasse is pretreated or mixed with more accessible carbon sources, and if mineral salts are added to the medium. On the other hand, spray drying of vinasse by was explored, using maltodextrin as a coadjuvant additive, in order to obtain dry vinasse. The use of dry vinasse as substrate resulted in a higher productivity of PHAs (0.0227 g.L-1 h-1) compared to the liquid vinasse. This increase could be attributed to the presence of maltodextrin, which would result in a more accessible carbon source for fermentation by Bacillus, in accordance with the results of the technical-economic feasibility study. The biosynthesized PHAs were subjected to molecular and thermal characterization using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and Thermogravimetric Analysis (TGA). The values of melting temperature of PHAs suggest that the biopolymer obtained could be identified as a copolymer of 3HB with longer monomers such as 3-HV, among others. Comparing the melting temperature with values reported in the literature the obtained PHAs could be a P(3HB-co-3HV) with an approximate concentration of 9 mo % HV. The advances in the optimization of the production of PHAs using vinasse as a substrate, the economic evaluation, the obtaining of dry vinasse and its use for the PHAs synthesis, and the biopolymer characterization allow progress towards more sustainable production of biodegradable polymers using renewable resources. In addition, experimental results obtained represent an important contribution to the biosynthesis of PHAs by cost- effective biotechnological processes.
2

Viabilidade técnica e econômica do uso de lithothamnium e vinhaça associado à irrigação na cana-de-açúcar / Viabilidad técnica y económica del uso de lithothamnium y viñaza asociado a la irrigación en caña de azúcar

Rodriguez, Walter Danilo Maradiaga 22 November 2017 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-12T11:55:46Z No. of bitstreams: 2 Tese - Walter Danilo Maradiaga Rodriguez - 2018.pdf: 4779250 bytes, checksum: b5a5007d18f65cc6eeda9a5b54dbac5a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-12T14:13:08Z (GMT) No. of bitstreams: 2 Tese - Walter Danilo Maradiaga Rodriguez - 2018.pdf: 4779250 bytes, checksum: b5a5007d18f65cc6eeda9a5b54dbac5a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-12T14:13:08Z (GMT). No. of bitstreams: 2 Tese - Walter Danilo Maradiaga Rodriguez - 2018.pdf: 4779250 bytes, checksum: b5a5007d18f65cc6eeda9a5b54dbac5a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-11-22 / Outro / The climatic and soil limitations of the state of Goias, the second largest producer of sugarcane in Brazil, have given challenges to the sugarcane sector. Because of this, the proper use of fertilizer and efficient irrigation are essential practices that are needed to increase the productivity and quality of sugarcane. However, it because economically necessary to analyze all activity that starts, to understand with details and use, in an intelligent and economical way, the factor of production. In this context, the objetive of this work was to evaluate the effect of irrigation and fertilization with lithothamnium mixed with vinasse, on productivity and technological characteristics of sugar in the “Cerrado” and evaluate under these cultivating conditions, the economical efficiency of the production of sugarcane in this area. For this, an experiment was conducted in the School of Agronomy of the Federal University of Goias. The variety of sugarcane used was the RB867515. The treatments correspond to five doses of vinasse (0, 65, 330, 495 and 660 m 3 ha -1 ), five doses of lithothamnium (0, 100, 200, 300 and 400 kg ha -1 ) and cultivated in an irrigated and rainfed regime. For the procedure for estimating the cost of production, regarded as the sum of values of all the resources and operations used in the productive process of the activity, it was used the calculation of depreciation and the alternative cost. The treatments applied influenced the productivity and technological characteristics of the sugarcane. Plants irrigated and fertilized with 200 kg ha -1 of lithothamnium and 330 m 3 ha -1 vinasse were the ones that presented the best results. The cultivation of organic sugarcane using the treatments in this work is economically viable for the region of the “Cerrado”. / As limitações edafoclimaticas do estado de Goiás, segundo maior produtor de cana-de-açúcar do Brasil, têm imposto desafios ao setor sucroenergético. Portanto o uso de adequada adubação e irrigação são práticas imprescindíveis para proporcionar aumento na produtividade e qualidade da cana-de-açúcar nessa região. Entretanto, torna-se necessário analisar economicamente toda atividade que se inicia, para conhecer com detalhes e utilizar de maneira inteligente e econômica, os fatores de produção. Nesse contexto, o objetivo desse trabalho foi avaliar o efeito da irrigação e adubação com lithothamnium combinado com vinhaça, sobre a produtividade e característicastecnológicas da cana-de-açúcar no cerrado, avaliando a eficiência econômica em cultivo orgânico e convencional. Para isso conduziu-se um experimento na Escola de Agronomia da Universidade Federal de Goiás. A variedade de cana-de-açúcar utilizada foi a RB867515. Os tratamentos corresponderam a cinco doses de vinhaça (0, 165, 330, 495 e 660 m 3 ha -1 ), cinco doses de lithothamnium (0, 100, 200, 300 e 400 kg ha -1 ) e cultivo em regime irrigado e de sequeiro. Para o procedimento de estimativa do custo de produção, conceituado como a soma de valores de todos os recursos e operações utilizados no processo produtivo da atividade, utilizou-se o cálculo da depreciação e do custo alternativo. Os tratamentos aplicados influenciaram a produtividade e características tecnológicas da cana-de-açúcar. Plantas irrigadas e adubadas com 200 kg ha -1 de lithothamnium e 330 m 3 ha -1 vinhaça, foram as que apresentaram os melhores resultados. O cultivo de cana-de-açúcar orgânica utilizando os tratamentos desse trabalho é viável economicamente para a região do cerrado goiano.
3

Propuesta de factibilidad para la producción y comercialización de un fertilizante orgánico a partir de la vinaza en la región Lambayeque / Feasibility proposal for the production and commercialization of an organic fertilizer from vinasse in the Lambayeque region

Reyna Díaz, Andy Maicol 17 September 2020 (has links)
El objetivo principal de este estudio fue establecer la viabilidad de la producción de un fertilizante orgánico, a partir de vinaza en la Región de Lambayeque, con la finalidad de maximizar el potencial de los cultivos orgánicos y residuos de vinaza, que es un subproducto de la destilación del alcohol. Para la producción de fertilizante orgánico se utiliza la vinaza, añadiendo pajilla de arroz en proporciones de 30% y 70%, logrando así la mejora de las propiedades del fertilizante, para una mejor interpretación del secado y su soldado mezcla. El proceso de producción de fertilizante orgánico se llevó a cabo utilizando muestras concentradas de vinaza divididas en tres grupos: 55 °Bx, 65 °Bx y 75° Bx, a las cuales se le agregaron una mezcla de pajilla, en proporciones de: 45%, 50% y 55% de vinaza y el resto en los grupos establecidos. Las pruebas, que se llevaron a cabo con la ayuda un laboratorio, revelaron que es posible elaborar abono orgánico a partir de la uva respetando los estándares establecidos. Finalmente, el proyecto si es viable dado que tiene un valor actual neto (VAN) de S/ 21,798,900.89, siendo el proyecto rentable. Además, la tasa interna de rentabilidad financiera (TIR) del 121%, lo que da por entendido que aparte de devolver el capital invertido, se podrá otorgar un adicional. / The main objective of this study was to establish the feasibility of producing an organic fertilizer from vinasse in the Lambayeque Region, in order to maximize the potential of organic crops and vinasse residues, which is a by-product of alcohol distillation. For the production of organic fertilizer, the vinasse is used, adding rice straw in proportions of 30% and 70%, thus improving the properties of the fertilizer, for a better interpretation of the drying and its welded mixture. The organic fertilizer production process was carried out using concentrated vinasse samples divided into three groups: 55 °Bx, 65 °Bx and 75 °Bx, to which a straw mixture was added, in proportions of: 45%, 50% and 55% of vinasse and the rest in the established groups. The tests, which were carried out with the help of a laboratory, revealed that it is possible to produce organic fertilizer from grapes while respecting the established standards. Finally, the project is viable given that it has a net present value (NPV) of S/ 21,798,900.89, making the project profitable. In addition, the internal rate of return (IRR) is 121%, which means that in addition to returning the invested capital, an additional amount can be granted. / Tesis

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