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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.
11

Hybridization with CSP in a Cuban sugar mill

Vesterberg, Iris, Westerlund, Sofia January 2018 (has links)
Kuba har i dagsläget ett högt beroende av importerad olja, för att tillgodose sin växande efterfrågan på elektricitet. Importen sker främst från Venezuela. Detta beroende gör Kuba känsligt för ändringar i oljepriser samt det politiska klimatet. Den nuvarande krisen i Venezuela har haft en betydande inverkan på Kubas elproduktion. Genom att utöka landets förnybara energikällor kan Kuba minska sitt beroende av andra länder och diversifiera sin energiförsörjning. Detta kommer även att leda till en positiv miljöpåverkan då landets CO 2-utsläpp minskar. Kubas geografiska läge har ideala förhållanden för förnyelsebar energigenerering, så som solkraft. Solkraft utvecklas konstant och innehåller en hög potential. Concentrating Solar Power (CSP) är en teknologi där speglar och/eller linser används för att koncentrera solljus till en liten yta som konverterar solljuset till värme. Denna värme kan sedan användas i termodynamiska cykler. Det finns två huvudsakliga problem med implementering av CSP på Kuba. För det första är CSP beroende av momentana väderförhållanden, vilket leder till en oregelbunden elproduktion. För det andra har CSP höga investeringskostnader. För att adressera dessa problem, är det möjligt att implementera CSP i ett redan existerande kraftverk med regelbunden energikälla, d.v.s. skapa ett hybridkraftverk. På så vis uppnås regelbunden elproduktion med signifikant lägre investeringskostnad. Ett sådant existerande kraftverk kan hittas hos många av Kubas sockerbruk. Den här studien undersöker möjligheten att implementera solkraft i sockerbruket Carlos Baliño, beläget i Villa Clara, Kuba. Fabriken är självförsörjande av elektricitet på årlig basis. De använder en Rankine-cykel för att generera el och processvärme som används i sockerframställningen. Bränslet som används är bagasse, en restprodukt efter att sockerjuicen pressats ut ur sockerrören. Fyra CSP-teknologier och tre implementeringslayouts undersöktes, vilket resulterade i att parabolic trough-teknologin och förvärmning av vatten ansågs vara de bästa alternativen för Kuba och Carlos Baliño. Vidare undersöktes två olika scenarier för CSP. Scenario 1 innefattar implementering av CSP i sockerbruket under rådande skick och Scenario 2 består av implementering av CSP efter en investering gjorts i en Condensing Extraction turbin (CEST). Resultatet visar att Carlos Baliño bör investera i CEST innan de implementerar CSP, det vill säga Scenario 2. Detta beror på att i scenario 1 är det inte möjligt att generera elektricitet utanför sockersäsongen, vilket leder till att en stor del av solpotentialen inte kan utnyttjas. Den maximala investeringskostnaden för scenario 1 är 3,7 MUSD, vilket inte är en realistisk kostnad. Den maximala investeringskostnaden för scenario 2 beror av tillgänglig bagasseimport och är 5,9 – 7,2 MUSD. Att investera i CSP rekommenderas ej om bagasseimporten är obegränsad. Givet att bagasseimporten är begränsad skulle CSP-implementeringen leda till en utökad elproduktion av 5,4 – 7,2 GWh/år, en årlig minskning av oljeanvändandet med 16 100 – 21 800 tunnor och minskade CO2-utsläpp med 12 00-16 00 ton årligen. Carlos Baliños ekonomiska resultat skulle öka med 0,5 MUSD/år och den kubanska statens med 0,7 – 0,9 MUSD/år. Framtida studier rekommenderas undersöka möjligheten till generering av el året runt vid Carlos Baliño utan en CEST, solkraftsefterfrågan på nationell nivå och potentiella utvecklingar av solkraft hos Carlos Baliño. / Cuba is currently highly dependent on imported oil, mainly from Venezuela, to meet their growing electricity demand. This dependence makes Cuba sensitive to changes in oil price as well as the political climate. The current crisis in Venezuela has a large impact on Cuba’s electricity generation. By expanding its renewable energy sources Cuba could decrease their dependence on other countries and diversify their energy supply. Moreover, it would have a positive climate impact by reducing the country’s CO2-emissions. Geographically, Cuba has ideal conditions for renewable energy utilization, such as solar power. Solar energy is constantly progressing and is considered a great source of energy. Concentrating Solar Power (CSP) is a technology which applies mirrors and/or lenses to concentrate the sunlight onto a small area which converts the sunlight into heat, possible to use in a thermodynamic cycle. There are mainly two problems with the implementation of CSP in Cuba. Firstly, CSP is a non-dispatchable power generating system since it is dependent on the instantaneous weather conditions. Secondly, it has high investment costs. One way of solving these problems is by implementation CSP in an already existing power plants with a dispatchable source of energy, making it a hybrid power plant. Accordingly, the hybrid power plant would be dispatchable and the investment costs would be significantly lower. Existing power plants can be found in Cuban sugar mills. This study investigates the possibility to implement solar power in the sugar mill Carlos Baliño, located in Villa Clara, Cuba. The factory is currently self-sufficient electricity wise on a yearly basis, using a co-generation Rankine cycle to generate electricity and process heat used in the sugar production. The fuel used is bagasse, a rest product obtained after the sugar juice has been pressed out of the sugar canes. Four CSP-technologies and three implementation layouts were examined, resulting in the parabolic trough-technology and feedwater heating being considered the optimal solution. Furthermore, two different scenarios for CSP was investigated; implementation of CSP in the mill at the current state (scenario 1) or after investing in a Condensing-Extraction Turbine (CEST) (scenario 2). The results show that Carlos Baliño should invest in a CEST before considering implementation of CSP. Off-season operation is not available for scenario 1, leading to a vast amount of solar potential being unexploited. The maximal investment allowed for scenario 1 is 3.7 MUSD, which is not a realistic number. The maximal investment allowed for in scenario 2 is 5.9 – 7.2 MUSD, depending on bagasse import availability. If bagasse import is unlimited, it is not recommended to invest in solar power. Implementation of CSP in scenario 2 regarding bagasse import limits would yearly lead to an additional electricity generation at Carlos Baliño of 5.4 – 7.3 GWh, decrease the oil usage with 16,100 – 21,800 barrels and the CO2-emissons with 1,200 – 1,600 tonnes. Carlos Baliño’s annual yield would increase with 0.5 – 0.6 MUSD/year and the Cuban states annual yield would increase with 0.7 – 0.9 MUSD/year. Future work is recommended to explore alternatives to all year-around electricity generation in Carlos Baliño without investing in a CEST, investigate solar power demand on a national level, and examine possible developments of the suggested solar field, for instance solar-only operation.
12

Bagasse as a Fuel for Combined Heat and Power (CHP): An Assessment of Options for Implementation in Iran.

Salehi, Farnza A. January 2011 (has links)
With over one hundred years of commercial cultivation, sugar cane is one of the most valuable agricultural botanical resources in the World. This position is not only based on production of sugar from sugar cane but also it is, to a great extent, as a result of the increasing importance of sugar cane by-products and side industries. Furthermore, with the advancement of science; awareness of inharmonious growth of materials and energy consumption, and the desire to minimize the negative impacts of industrial pollutants and materials, the scope for using sugar cane is still developing rapidly. Bagasse, molasses and filtered mud are the most important by-products in the process of production of sugar from sugar cane. Among these by-products, bagasse is both a biomass resource for producing energy and is one of the most important agricultural wastes, which can be used in different side industries. Therefore, it was chosen for study in this research as it offers considerable potential as a source of energy. Bagasse is often used as a primary fuel source for sugar mills; when burned in quantity, it produces sufficient heat energy to supply all the needs of a typical sugar mill, with energy to spare. To this end, today a secondary use for this waste product is in combined heat and power plants where its use as a fuel source provides both heat and power. With a suitable energy production technology, bagasse can be used as a fuel in CHP for high efficiency energy generation. Today, with regard to the low efficiency of traditional methods, the high cost of disposal of waste materials and environmental pollution, the use of modern methods such as anaerobic digestion for the production of biogas has increased. The collected biogas from the process of anaerobic digestion provides a renewable energy source similar to natural gas, but with less methane and lower heating value, that is suitable for use in CHP plants. In this research, a comparison with different bagasse energy production technologies leads to the selection of anaerobic digestion as the most suitable for use in Iran. Then a typical biogas CHP is assumed, and the biogas system is designed. Finally, the potential for the development of biogas CHP plants with bagasse in Iran is addressed through a study of the economic and environmental aspects.
13

A INDÚSTRIA CANAVIEIRA E AS NOVAS RELAÇÕES DE TRABALHO DO ESTADO DE GOIÁS

Camargo, Adriana Lourenço 14 August 2009 (has links)
Made available in DSpace on 2016-08-10T10:45:26Z (GMT). No. of bitstreams: 1 ADRIANA LOURENCO CAMARGO.pdf: 1542026 bytes, checksum: 64215c83c4bb1f4bb27ade7a01443943 (MD5) Previous issue date: 2009-08-14 / This work approached itself reflections about sustainability, development of the cane in Brazil and in the State of Goiás and the applicable legislation to the sugar cane worker. Having in mind the workers liberation cases relapses of the cane that were submitted to the works forced or analogous to the work slave. With population growth to food production to meet increased population demands. In this context the culture of the sugar-cane expanded dizzily for the whole country with intention of not only providing the national necessities. In this productive process of the sugar-cane there emerge the labor relations resulted from the sugar cane enterprise with his cutting employees of cane. From the point of view of the sustainable, that relation of work, the current legislation referring to a rural sugar cane worker and the social reality of the sugar cane healthy sector, in this study, boarded. In this composition analyzes-itself the efficacy of the applicability of the collective convention of the sugar cane sector, through the descriptive study of the sugar cane expansion and the relation of work with the cutters of cane. / Este trabalho abordou reflexões sobre expansão de lavouras de cana-de-açúcar no Brasil e no estado de Goiás e a legislação aplicável ao trabalhador canavieiro. Tendo em vista as reincidências de casos de libertação de trabalhadores da cana que foram submetidos à trabalhos forçados ou análogos à trabalho escravo. Com o crescimento da população a produção de alimentos cresceu para suprir a demanda populacional. Dentro deste contexto a cultura da cana de açúcar expandiu vertiginosamente por todo o país com intuito de não só suprir as necessidades nacionais. Neste processo produtivo da cana de açúcar afloram as relações trabalhistas advindas da empresa canavieira com seus empregados cortadores de cana. Do ponto de vista da sustentabilidade, aquela relação de trabalho, a legislação atual referente ao trabalhador rural canavieiro e a realidade social do setor canavieiro são, neste estudo, abordadas. Nesta composição analisa-se a eficácia da aplicabilidade da convenção coletiva do setor canavieiro, através do estudo descritivo da expansão canavieira e a relação de trabalho com os cortadores de cana.
14

Fermentação anaeróbia para formação de ácido caproico a partir de produtos e subprodutos da cadeia produtiva da cana-de-açúcar / Anaerobic fermentation for caproic acid training from products and by-products of the sugarcane industry

Willame de Araújo Cavalcante 09 May 2016 (has links)
O ácido caproico é derivado da cadeia petroquímica e, tem diversas aplicações na indústria química. No entanto, este ácido pode ser produzido de forma mais ambientalmente adequada, a partir da fermentação anaeróbia. O objetivo dessa pesquisa foi investigar condições operacionais para a formação anaeróbia de ácido caproico a partir de produtos e subprodutos da indústria sucroalcooleira. Utilizou-se um reator anaeróbio de manta de lodo e fluxo ascendente (UASB - Upflow Anerobic Sludge Blanked), com volume útil de 13,8 L, alimentado com substratos simples (etanol e ácido acético) ou com substrato complexo (fermentado alcoólico de melaço de cana). Durante a operação do reator UASB, a COV variou de 2,0 a 5,5 gDQO.L-1.d-1 em pH ácido (5,3). A taxa de produção volumétrica de ácido caproico a partir de substrato simples (1,0 gC6.L-1.d-1) em reator UASB foi superior àquela com substrato complexo (0,2 gC6.L-1.d-1). Em pH de aproximadamente 5,3, a produção de ácido caproico ficou limitada a um valor de aproximadamente 2,8 gC6. L-1 devido a maior presença de ácidos não dissociados. Utilizando fermentado de melaço de cana contendo etanol (150 mM de etanol), é possível atingir uma produção de até 4,0 gC6. L-1 em pH com adição clorofórmio como inibidor seletivo para organismos metanogênicos. A presença de ácido acético acelera a formação de ácido butírico, resultando no acúmulo deste devido à ausência de etanol como doador de elétrons. Dessa forma, a formação de ácido caproico a partir de fermentado de melaço de cana não necessita da adição externa de ácido acético. É necessária extração seletiva do ácido caproico, evitando o acumulo indesejado. / Caproic acid is derived from the petrochemical production chain and has many applications in the chemical industry. However, this acid can be produced in a more environmental friendly technological route, using the anaerobic fermentation. The objective of this research was to investigate the operational conditions for anaerobic caproic acid formation using the products and by-products of the sugarcane industry. We used an upflow anaerobic sludge blanket and upflow (UASB - Upflow Sludge anerobic Blanked), with a working volume of 13.8 L, fed with simple substrates (ethanol and acetic acid) or complex substrate (undistilled fermented molasses). During the UASB reactor operation, OLR ranged from 2.0 to 5.5 gDQO.L-1.d-1 at acid pH (5.3). The volumetric production rate of caproic acid from simple substrates (1.0 gC6.L-1.d-1) in UASB reactor was superior to that from complex substrate (0.2 gC6.L-1.d-1). At pH of approximately 5.3, caproic acid production was limited to a value of approximately 2.8 gC6.L-1 due to the greater presence of non-dissociated acids. Using fermented sugar cane molasses containing ethanol (150 mM ethanol), can be achieved a production of up to 4.0 gC6.L-1 in pH by adding chloroform as a selective inhibitor for methanogenic organisms. The presence of acetic acid accelerates the formation of butyric acid, resulting in the accumulation of this due to the absence of ethanol as an electron donor. Thus, the formation of caproic acid from fermented molasses does not require the external addition of acetic acid. It is necessary selective extraction of caproic acid, preventing unwanted accumulation.
15

Responsabilidade social nas agroindústrias canavieiras no Brasil. / Social responsibility of the Brazilian sugar cane industry

Wissmann, Martin Airton 16 March 2017 (has links)
Submitted by Marilene Donadel (marilene.donadel@unioeste.br) on 2017-08-22T20:24:32Z No. of bitstreams: 1 Martin A Wissmann 2017.pdf: 3822721 bytes, checksum: 992e1d91cf4dd49b947b2eec048496a4 (MD5) / Made available in DSpace on 2017-08-22T20:24:32Z (GMT). No. of bitstreams: 1 Martin A Wissmann 2017.pdf: 3822721 bytes, checksum: 992e1d91cf4dd49b947b2eec048496a4 (MD5) Previous issue date: 2017-03-16 / This research examines the social responsibility of the sugar cane industry in Brazil and analyzes how economic, environmental and social dimensions influence socially responsible behavior. A theoretical survey was carried out to identify origin, development and main concepts of social responsibility, pointing out its indicators, principal models and users and/or beneficiaries of social sustainability reports. Furthermore, the main theories related to socially responsible behavior were explored in order to support the composition of research tools and the analysis of results. The GRI-G4 model elaborated by the Global Reporting Initiative served as an additional resource. Purposing to show the relation between theme and object of this study, the sugar cane industry was characterized, presenting its economic, environmental and social impacts and further researches relating social responsibility and economic activity of this industry. The applied methodology consisted of explanatory, quantitative and qualitative research, utilizing questionnaires of a total population of 184 sugar cane industries (individuals or groups of companies), getting a return of 128, representing 5% margin of error and 96% confidence interval. In order to attest the hypothesis, modelling of structural equations by SmartPLS were applied. The results demonstrate that Brazilian sugar cane industry has reached an advanced stage in relation to the importance and practical accomplishment of the socially responsible actions raised by the research, but demonstrate the need to advance, mainly, the evidence of these actions. It also showed that the social dimension exerts major influence when compared to the other dimensions in the CSR. / O objetivo desta pesquisa é identificar como se encontra a Responsabilidade Social nas Agroindústrias Canavieiras no Brasil no tocante às dimensões econômica, ambiental e social, e analisar qual a influência relativa de cada uma delas no comportamento socialmente responsável. Para isso, foi realizado um levantamento teórico a fim de identificar a origem, evolução e conceituação da Responsabilidade Social, destacando os indicadores, os principais modelos e usuários e/ou beneficiários dos relatórios de sustentabilidade. Levantou-se, também, as teorias que apresentam relação com o comportamento socialmente responsável, que deram suporte para composição do instrumento de pesquisa e para análise dos resultados, juntamente com as orientações disponibilizadas pela Global Reporting Initiative (instituição reconhecida internacionalmente e que disponibiliza o modelo GRI-G4, que serve de apoio para as empresas que querem desenvolver e divulgar as ações socialmente responsáveis). Visando mostrar a relação entre o tema e o objeto de estudo promoveu-se a caracterização da agroindústria canavieira, demonstrando o seu impacto econômico, ambiental e social, além de apresentar alguns estudos que mostram a relação da Responsabilidade Social com esta atividade. Este trabalho adotou como procedimento metodológico as pesquisas de natureza explicativa, quantitativa e qualitativa. Como instrumento de pesquisa aplicou-se um questionário a um universo de 184 agroindústrias canavieiras (individuais ou grupo de empresas), obtendo retorno de 128 questionários, o que representou 5% de margem de erro e 96% de margem de confiança. Para a validação das hipóteses, foi utilizada a modelagem de equações estruturais, aplicada por meio do SmartPLS. Os resultados demonstraram que as agroindústrias canavieiras no Brasil se encontram em estágio avançado em relação a importância e realização prática das ações socialmente responsáveis levantadas pela pesquisa, porém demonstram a necessidade de avançar, principalmente, na evidenciação dessas ações. Demonstrou, também, que a dimensão social exerce maior influência quando cotejada com as demais dimensões, no CSR.
16

Fermentação anaeróbia para formação de ácido caproico a partir de produtos e subprodutos da cadeia produtiva da cana-de-açúcar / Anaerobic fermentation for caproic acid training from products and by-products of the sugarcane industry

Cavalcante, Willame de Araújo 09 May 2016 (has links)
O ácido caproico é derivado da cadeia petroquímica e, tem diversas aplicações na indústria química. No entanto, este ácido pode ser produzido de forma mais ambientalmente adequada, a partir da fermentação anaeróbia. O objetivo dessa pesquisa foi investigar condições operacionais para a formação anaeróbia de ácido caproico a partir de produtos e subprodutos da indústria sucroalcooleira. Utilizou-se um reator anaeróbio de manta de lodo e fluxo ascendente (UASB - Upflow Anerobic Sludge Blanked), com volume útil de 13,8 L, alimentado com substratos simples (etanol e ácido acético) ou com substrato complexo (fermentado alcoólico de melaço de cana). Durante a operação do reator UASB, a COV variou de 2,0 a 5,5 gDQO.L-1.d-1 em pH ácido (5,3). A taxa de produção volumétrica de ácido caproico a partir de substrato simples (1,0 gC6.L-1.d-1) em reator UASB foi superior àquela com substrato complexo (0,2 gC6.L-1.d-1). Em pH de aproximadamente 5,3, a produção de ácido caproico ficou limitada a um valor de aproximadamente 2,8 gC6. L-1 devido a maior presença de ácidos não dissociados. Utilizando fermentado de melaço de cana contendo etanol (150 mM de etanol), é possível atingir uma produção de até 4,0 gC6. L-1 em pH com adição clorofórmio como inibidor seletivo para organismos metanogênicos. A presença de ácido acético acelera a formação de ácido butírico, resultando no acúmulo deste devido à ausência de etanol como doador de elétrons. Dessa forma, a formação de ácido caproico a partir de fermentado de melaço de cana não necessita da adição externa de ácido acético. É necessária extração seletiva do ácido caproico, evitando o acumulo indesejado. / Caproic acid is derived from the petrochemical production chain and has many applications in the chemical industry. However, this acid can be produced in a more environmental friendly technological route, using the anaerobic fermentation. The objective of this research was to investigate the operational conditions for anaerobic caproic acid formation using the products and by-products of the sugarcane industry. We used an upflow anaerobic sludge blanket and upflow (UASB - Upflow Sludge anerobic Blanked), with a working volume of 13.8 L, fed with simple substrates (ethanol and acetic acid) or complex substrate (undistilled fermented molasses). During the UASB reactor operation, OLR ranged from 2.0 to 5.5 gDQO.L-1.d-1 at acid pH (5.3). The volumetric production rate of caproic acid from simple substrates (1.0 gC6.L-1.d-1) in UASB reactor was superior to that from complex substrate (0.2 gC6.L-1.d-1). At pH of approximately 5.3, caproic acid production was limited to a value of approximately 2.8 gC6.L-1 due to the greater presence of non-dissociated acids. Using fermented sugar cane molasses containing ethanol (150 mM ethanol), can be achieved a production of up to 4.0 gC6.L-1 in pH by adding chloroform as a selective inhibitor for methanogenic organisms. The presence of acetic acid accelerates the formation of butyric acid, resulting in the accumulation of this due to the absence of ethanol as an electron donor. Thus, the formation of caproic acid from fermented molasses does not require the external addition of acetic acid. It is necessary selective extraction of caproic acid, preventing unwanted accumulation.
17

Certificação ambiental e desenvolvimento sustentável: avaliação para o setor sucroalcooleiro localizado na bacia hidrográfica do rio Mogi-Guaçi/SP. / Eenvironmental certification and sustainable development: avaliation for the sugar cane industry in the hydrographic basin of the river Mogi-Guaçu / SP

Rodrigues, Isabel Cristina 02 April 2004 (has links)
Made available in DSpace on 2016-06-02T19:50:07Z (GMT). No. of bitstreams: 1 TeseICR.pdf: 3185739 bytes, checksum: 16649590613a10440edd9845ba2ad3ab (MD5) Previous issue date: 2004-04-02 / Universidade Federal de Minas Gerais / The sugar cane culture always was been associated, throughout its history, with ambient degradation and social contingencies. The positioning, on the part of the sugar cane industry, with relation to the negative impacts of its activity on the environment has been defensive, limited to fulfill the legal impositions. In this context, calls the attention the initiative of some sugar cane plants that had decided to produce certified sugar cane and certified organic sugar. This work discusses the motivations that had taken these plants to adopt this system of production and the factors that had concurred for this decision. It starts from the hypothesis that the basic motivation for this decision was the search for a differentiated product, with characteristics valued for the market, and, therefore, apt to increase the profit tax and valuing the capital. The work also allows analyzing until with point the premises of the Sustainable Development are observed by the plants when of its decisions of investments. From of the definition of that the sustainable development must incorporate the regional questions, the sugar cane industry in the Hydrographic Basin of the river Mogi-Guaçu was chosen for the study, because it is in this basin that is found the biggest productive portion of this sector in the country. The research carried through in one of the productive units in the Basin allowed to the construction of a diagnosis of the activity in the regional clipping and a delineation of the necessary changes to the organic production. The resultant diagnosis of the field research allowed concluding that the environment conditions of the plants that had opted to the organic production are significantly improved, but the premises foreseen by the organic certification are incapable to contemplate all the social and environment problems of this activity. The main problems are associated to the extensive exploration of the agricultural activity and the questions of exclusion of workers and small suppliers, generating social problems in the region of the enterprise. The analysis of the plants that had opted to the conversion demonstrates different strategies between them, but the research points out that the motivation that had taken them to decide for the conversion, was directed by the search for a differentiated product. The work concludes that the tools of ambient regulation, based in the market demand, as it is the case of the certificates and labels, is insufficient to contemplate all the premises of the regional sustainable development and that still it becomes necessary the performance of the State and its agencies in the regulation of the access, use and of the occupation of the agricultural space. / A atividade canavieira sempre esteve associada, ao longo de sua história, a quadros de degradação ambiental e contingências sociais. O posicionamento por parte da agroindústria canavieira com relação aos impactos negativos de sua atividade sobre o meio ambiente tem sido defensivo, se limitado a cumprir as imposições legais. Neste cenário, chama atenção a iniciativa de algumas usinas do setor que decidiram produzir cana-de-açúcar e açúcar orgânico certificado. Este trabalho discute as motivações que levaram estas usinas a adotarem este sistema de produção e as condicionantes que concorreram para esta decisão. Parte-se da hipótese que a motivação fundamental para esta decisão foi a busca por um produto diferenciado, com características valorizadas pelo mercado. Este trabalho também permite analisar até que ponto as necessidades associadas às premissas do Desenvolvimento Sustentável são observadas pelas usinas quando de suas decisões de investimentos em um produto diferenciado por atributos de preservação ambiental como é o açúcar orgânico. Partindo da definição de que o desenvolvimento sustentável deve incorporar a questão regional, escolheu-se para o estudo o setor sucroalcooleiro localizado na Bacia Hidrográfica do rio Mogi-Guaçu, pois é nesta bacia que se encontra a maior porção produtiva do setor e, além disto, há na região duas unidades produzindo o açúcar orgânico. A pesquisa em uma amostra das unidades produtivas situadas na Bacia permitiu a construção de um diagnóstico socioambiental da atividade no recorte regional e um delineamento das mudanças necessárias para a conversão à produção orgânica. O diagnóstico resultante da pesquisa de campo permitiu concluir que as condições ambientais das usinas que optaram pela produção orgânica são sensivelmente melhoradas, mas as premissas previstas pela certificação orgânica são incapazes de contemplar todos os constrangimentos socioambientais desta atividade. Os principais problemas estão associados à exploração extensiva (monocultura) da atividade agrícola e as questões de exclusão de mão-de-obra e de pequenos fornecedores, gerando problemas sociais na região do empreendimento. A análise das usinas que optaram pela conversão demonstra estratégias diferentes entre elas, mas a pesquisa aponta que a motivação que as levaram decidir pela conversão, foi calcada na busca por um produto diferenciado, apto a ingressar em nichos de mercado com um preço valorizado. O trabalho conclui que as ferramentas de regulação ambiental, baseadas na demanda de mercado, como é o caso dos certificados e selos, são insuficientes para contemplar todas as premissas do desenvolvimento sustentável regional e que ainda se faz necessário a atuação do Estado e suas agências na regulação do acesso, uso e da ocupação do espaço agrícola.
18

Análise da competitividade do setor sucroenergético na região Nordeste

Oliveira, Marco Aurélio Déda 06 July 2012 (has links)
The aim of this work is to analyze the competitiveness of ethanol, sugar and bioenergy industry installed in the Northeast of Brazil, comparing it to established industry in the Mid-South economic region. The growth occurred since 2004 in production and consumption of ethanol in Brazilian and international markets has encouraged the inflow of new entrants in the Brazilian ethanol, sugar and bioenergy industry and increased competitiveness. However, this expansion occurs disproportionately between the two economic regions in the country, generating a big disproportion related to the industrial units sizes installed in each region. This fact alerts to the economic viability question of businesses in Northeast because its industry is a commodities one, sensitive to prices, production efficiency, and especially the production scale. Therefore, this research sought to understand if Northeast firms are able to compete in the new context of Brazilian sugarcane industry. To achieve the objectives proposed in this study, three concepts of competitiveness were used, based in Kupfer (1992), Kupfer (1996), Kupfer (1998) and Ferraz, Kupfer and Haguenauer (1996): competitiveness as performance, competitiveness as productive efficiency and competitiveness as the ability to adhere to the standards of Brazilian ethanol, sugar and bioenergy industry. / O objetivo deste trabalho é avaliar a competitividade da indústria sucroenergética instalada na região Nordeste, comparando-a com a indústria estabelecida na região Centro-Sul do país. O crescimento ocorrido a partir de 2004 na produção e no consumo de etanol nos mercados brasileiro e internacional tem estimulado o aporte de novos entrantes na indústria sucroenergética brasileira e o aumento na competitividade setorial. Observa-se, entretanto, que esta expansão ocorre de forma desproporcional entre as duas regiões econômicas do país, gerando uma imensa distorção entre o porte das unidades industriais instaladas em cada uma delas. Tal fato coloca em xeque a capacidade de sobrevivência das empresas nordestinas, uma vez que esta é uma indústria de commodities, sensível a preços, à eficiência produtiva e, especialmente, à escala de produção. Neste sentido, esta pesquisa buscou entender se as empresas nordestinas têm capacidade de competir no novo cenário que se desenha para o setor sucroenergético brasileiro. Para alcançar os objetivos propostos neste estudo, fez-se uso dos três conceitos de competitividade analisados por Kupfer (1992), Kupfer (1996), Kupfer (1998) e Ferraz, Kupfer e Haguenauer (1996), que são: competitividade como desempenho, competitividade como eficiência produtiva e competitividade como a capacidade de aderência das empresas nordestinas aos padrões de concorrência da indústria sucroenergética brasileira, conforme proposta destes autores.
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Exploration e exploitation na estratégia de diversificação da indústria sucroalcooleira paulista

Santos, Fábia Maria Silva Lins dos 16 August 2007 (has links)
Made available in DSpace on 2016-03-15T19:26:31Z (GMT). No. of bitstreams: 1 Fabia Maria Silva Lins dos Santos.pdf: 2368363 bytes, checksum: b7f60e810f9885e4ab828fa7fb8ba2a0 (MD5) Previous issue date: 2007-08-16 / Fundo Mackenzie de Pesquisa / Traditionally, the sugar cane sector is commodities industry and rarely innovate its portfolio, although researches have shown that some firms inside the sector have been using portfolio diversification strategies in the search of growth. Inside these strategies, the firms have made choices to: prospect new knowledge (exploration) or take advantage of not utilized competencies (exploitation). The use of knowledge is part of sectoral systems of innovation due to actors and institutions interaction. Using an exploratory and multicase and multistrategy study, this project wants to verify which processes exploration or exploitation is predominant on diversification strategy of sugar cane firms. The main contribution of this study are related to three main objectives: (1) identify characteristics of diversification in the sugar cane plants; (2) distinguish the processes of exploration and exploitation in these plants; (3) present evidences that support the presupposition of sugar cane sector being a sectoral systems of innovation. The results have shown that, from a total of nine firms, eight of them developed diversification strategies, related to Penrose (1959) classification of diversification. All of them participated in the sectoral systems of innovation, interacting in major or minor degree. All researched firms presented process related to exploitation, but their punctuation in exploration may explain their search for diversification. The high punctuation at exploration of some firms suggests it may be an explanation of their differentiated portfolio. Furthermore they showed intensive interaction with universities and research entities, in the search for new knowledge. These findings where consistent with the main objective defined in this project. It is expected that the present study might support future researches upon knowledge generation in firms oriented to diversification strategies. / Tradicionalmente, o setor sucroalcooleiro é um produtor de commodities e raramente inova sua carteira de produtos, embora algumas pesquisas demonstrem que firmas dentro do setor têm usado estratégia(s) de diversificação destas carteiras para buscar crescimento. Para atingir esta(s) estratégia(s), as firmas fazem escolhas entre: prospectar conhecimento novo (exploration) ou aproveitar competências não utilizadas (exploitation). O uso do conhecimento é característico dos sistemas setoriais de inovação devido à interação entre seus atores e instituições. Através de um estudo exploratório, mediante a aplicação de estudo multicasos e pesquisa de múltipla estratégia (quantitativa e qualitativa), buscou-se verificar qual dos processos exploration ou exploitation predomina na estratégia de diversificação das firmas sucroalcooleiras. As principais contribuições deste estudo relacionaram-se a três objetivos específicos: (1) identificar características de diversificação presentes nas usinas estudadas; (2) caracterizar os processos de exploration e exploitation nessas usinas; (3) apresentar argumentos que suportem o pressuposto de que o setor sucroalcooleiro é um sistema setorial de inovação. Os resultados apontaram que oito entre nove usinas pesquisadas apresentaram algum tipo de diversificação, de acordo com a classificação de Penrose (1959). Todas as usinas apresentaram participação no sistema setorial em menor ou maior grau e processos voltados à exploitation, mas observou-se que a pontuação em exploration pode ser um fator que explica a busca pela diversificação produtiva. As usinas com valores altos em exploration foram aquelas que apresentaram uma carteira de produtos diferenciada e também nas quais observou-se uma interação maior com universidades e entidades de pesquisa, buscando a prospecção do conhecimento. Espera-se que o presente estudo possa apoiar futuras pesquisas sobre geração de conhecimento em firmas voltadas a estratégias de diversificação.
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Impacts agronomiques et environnementaux de l'épandage de vinasse et de cendre de charbon/bagasse sur les terres agricoles de l'Île Maurice / Agronomic and environmental impacts of application of coal/bagasse ash and vinasse to sugarcane fields in Mauritius

Soobadar, Aneeza 07 July 2009 (has links)
Des 85 000 hectares de terres agricoles à l’île Maurice, prés de 85% est occupé par la canne à sucre, le reste étant composé de maraîchage et des cultures fruitières. Pour assurer sa pérennité et sa viabilité économique à long terme, l’industrie cannière s’appuie dans son programme de réforme sur une revalorisation de ses sous produits en développant une industrie d’éthanol à partir de la mélasse et en utilisant plus efficacement la bagasse durant la période de récolte pour produire l’électricité. Cependant ces deux filières génèrent beaucoup de déchets (400 000 T/an de vinasse durant la distillation d’éthanol, et 40 000 T/an de la cendre de charbon/bagasse durant la production d’énergie électrique), qu’il faudrait valoriser et gérer avec le moins d’effet néfaste possible sur l’environnement. Parmi les moyens disponibles pour la gestion de ces déchets, le recyclage agricole semble être le plus attrayant du point de vue agronomique et également sous l’aspect de protection de l’environnement. Dans ce contexte pour valider cette pratique de recyclage agricole à l’Île Maurice, une étude a été entreprise pour connaître les effets de l’épandage de fortes doses de vinasse et des cendres de bagasse/charbon sur les sols, la culture de la canne à sucre et sur la qualité des ressources en eau. L’analyse de la vinasse et de la cendre de charbon et de bagasse échantillonnées à intervalle régulier de trois mois entre 2005 et 2008 a montré que leur composition chimique est très variable. Néanmoins la caractérisation de la vinasse a confirmé qu’avec sa teneur en K (moyenne de 9.37 g/L), elle est utile principalement comme engrais potassique quoiqu’à un taux de 100 m3/ha son apport en termes d’azote (moyenne de 122 kg N/ha) et en matière organique (8-15% de matière sèche) sera aussi appréciable. Des métaux lourds (Cu, Zn, Ni, Mn, Pb) étaient également présents dans la vinasse mais leurs concentrations étaient négligeables et ne dépassaient souvent pas la limite de détection du spectrophotomètre d’absorption atomique utilisé pour la mesure (5 mg/kg pour le Cu, Zn, Ni, Pb, 10 mg/Kg pour le Mn) A l’opposé de la vinasse qui est acide (pH de 4.5 en moyenne), la cendre de bagasse ou de charbon possède un pH alcalin variant entre 7.5 à 11.5, et peut de ce fait, être utilisée comme amendement pour corriger l’acidité dans les sols. Appliquée à un taux de 100 T/ha, la cendre de charbon représenterait une source importante de potassium (moyenne de 139 kg K/ha) et surtout de phosphore (moyenne de 298 kg P/ha) à la canne à sucre. Contenant très peu de métaux lourds (Cu, Zn, Ni, Mn, Pb et Hg) et en général pas de micropolluants organiques, la cendre de charbon ne risque pas d’accentuer la présence de ces polluants organiques ou inorganiques dans le sol, dans la canne à sucre ou dans la nappe phréatique. Les études au laboratoire ont par contre démontré que la cendre de bagasse/charbon était capable de fortement immobiliser par adsorption, les herbicides atrazine et hexazinone avec des valeurs de Km (coefficients de sorption) de 0.13 pour atrazine et 0.32 pour hexazinone, rendant minime le risque de transfert de ces herbicides vers la nappe souterraine. Les analyses de sol ont confirmé que l’apport de la vinasse baissait le pH (de 5.9 à 5.4 en moyenne), mais cette baisse n’était que temporaire et pas assez significative pour affecter la croissance de la canne. Le pH du sol retournait à sa valeur initiale peu de temps après l’épandage de 100 m3/ha de la vinasse. La cendre de charbon avait eu un effet inverse en augmentant le pH du sol quoique cette hausse ne fût également pas significative pour la culture de la canne. Epandues à 100 m3/ha et à 100 T/ha la vinasse et la cendre de charbon, respectivement, avaient tendance à hausser la salinité du sol qui restait toutefois bien en dessous du seuil de 1700 RS/cm acceptable pour la culture de la canne à sucre. Si la vinasse à 100 m3/ha augmentait le carbone organique dans certains sols, tel ne fut cependant pas le cas pour la cendre de charbon à 100 T/ha. La vinasse comme la cendre de charbon avait un effet positif sur le niveau de calcium et de magnésium échangeables dans le sol. Ainsi à 100 T/ha la cendre de charbon augmentait dans le sol de Pamplemousses le Ca échangeable de 3.40 à 6.61 cmol+/kg après 12 mois, tandis que durant cette même période la vinasse à 100 m3/ha, et malgré sa forte teneur en potassium, portait le Ca échangeable de 1.66 à 1.83 cmol+/kg dans le sol de Union Park. Les essais aux champs établis dans quatre localités avec des doses croissantes de vinasse (25, 50 et 100 m3/ha) ont montré que le rendement de la canne à sucre que ce soit sous forme de canne ou de sucre n’était pas affecté de façon négative par ce déchet. Au contraire les résultats obtenus durant les trois années d’étude, qui ont permis de récolter une canne vierge et deux repousses, ont démontré que la vinasse avait donné un meilleur rendement en canne (moyenne de 84.9 T/ha annuellement pour les quatre sites) que le traitement recevant NPK uniquement sous forme d’engrais minéraux (moyenne de 77.3 T/ha annuellement pour les quatre sites). Puisque tous les traitements avaient reçu le même taux d’azote et de phosphate, ce rendement plus élevé de la vinasse était A part une meilleure nutrition potassique, probablement dû à une amélioration de la qualité du sol grâce aux matières organiques apportées par la vinasse. D’autre part, la cendre de charbon à 100 T/ha était définitivement néfaste à la canne à sucre comme indiqué par le rendement en canne plus faible (moyenne de 67.5 T/ha annuellement pour les quatre sites). A 50 T/ha, l’effet de la cendre de charbon sur le rendement dépendait du type de sol, étant plus affecté dans les sols lessivés comme à Belle Rive que dans les sols moins lessivés de la zone sous humide comme à Pamplemousses. En raison de leur faible teneur en métaux lourds, la vinasse aussi bien que la cendre de charbon n’ont pas d’effet sur la concentration des métaux lourds présents dans la canne à sucre. Pour connaître l’effet de l’épandage de 100 m3/ha de vinasse et de 100 T/ha de cendre de bagasse sur la qualité des eaux souterraines, l’eau percolant après chaque grosse pluie à un mètre de profondeur sous des lysimètres établis sur deux sites avec une pluviométrie différente (1500 mm/an à Réduit et plus de 3500 mm/an à Belle Rive) avait été recueillie et analysée durant la période 2005 à 2008. Les résultats ont montré que la vinasse à 100 m3/ha n’accentuait pas les pertes d’azote sous forme de nitrate. Les métaux lourds les plus mobiles en l’occurrence le cuivre, le zinc et le nickel ont également été retrouvés dans les percolâts mais leurs teneurs restaient bien en dessous des seuils recommandés pour l’eau potable préconisé par l’Organisation Mondiale de la Santé , c'est-à-dire, 1mg Cu/L, 5mg Zn/L et 0.02 mg Ni/L. Les résultats de quenching de fluorescence de la matière organique dissoute de la vinasse et de ses fractions (issues de la dialyse) avec le cuivre ont confirmé une bonne complexation entre cette matière organique dissoute et le cuivre. La cendre de bagasse n’avait pas engendré une présence plus prononcée des métaux lourds et des micropolluants organiques dans les eaux drainant à un mètre de profondeur des lysimètres. La seule différence remarquée entre la vinasse et la cendre de bagasse, était une capacité accrue de cette dernière à mobiliser le nitrate dans le sol. Ainsi suite à l’apport de 100 T/ha de cendre de bagasse, la concentration du nitrate dans les percolâts avait durant la période de novembre 2005 à février 2008 dépassé en de nombreuses occasions à Belle Rive et Réduit respectivement, le seuil de 10 mg N-NO3- /L recommandé pour l’eau potable par l’Organisation Mondiale de la Santé. En conclusion, cette étude a donné des résultats forts intéressants et valables qui indiquent que si l’épandage des fortes doses de vinasse peut être accepté, celle de la cendre de charbon est à éviter puisqu’elle n’est pas sans conséquence nuisible pour les sols ou les cultures et même les eaux souterraines. En effet, les fortes doses de cendre de charbon dans les champs de canne à l’île Maurice, conduiraient à une baisse de production et à une pollution plus accentuée de la nappe souterraine par le nitrate / Of the 85 000 hectares of arable land in Mauritius, sugar cane occupies some 85% of that area, the remainder is made up mostly of vegetables and fruit trees. To ensure its economic viability and long term sustanainability, the sugar cane industry through a reform program is striving to add value to its by-products by producing ethanol from molasses and by optimizing energy production from bagasse during the harvest season. However these two avenues generate considerable wastes (400 000 T/yr of vinasse during ethanol distillation and 40 000 T/yr of coal/bagasse ash during the production of electricity), which have to be judiciously disposed of with a minimum of risk to the environment. Among the disposal means for these wastes, the application of vinasse and coal/bagasse ash to agricultural land is believed to represent the most sensible economic option from both the agronomic and environmental point of view. In this context before recommending elimination of the wastes through disposal on agricultural lands, a study has been conducted to determine the effects of high doses of vinasse and coal/bagasse ash on soil quality, on the sugar cane plant and on groundwater quality. Analyses of vinasse samples collected at regular intervals of three months during 2005 to 2008 showed that its chemical composition was very variable. However these analyses also showed that as vinasse contained on average 9.37 g/L of K, its fertilization value was mostly as a source of potassium. Nevertheless at an application rate of 100 m3/ha vinasse, it can in addition represent a significant source of N (average of 122 kg N/ha) and of organic matter (average of 8-15 % dry matter). Vinasse also contained heavy metals (Cu, Zn, Ni, Mn, Pb) but their concentrations were negligible and were well below the detection limit of the atomic absorption spectrophotometer (5 mg/kg for Cu, Zn, Ni, Pb and 10mg/kg for Mn). As opposed to vinasse which is acidic in nature (an average pH of 4.5), coal or bagasse ash is alkaline with a pH varying between 7.5 and 11.5 and can therefore be used to amend soil acidity. When applied at 100 T/ha coal ash would represent a significant source of potassium (average of 139 kg K/ha) and of phosphorus (average of 298 kg P/ha) to the sugar cane crop. Due to its low contents of heavy metals (Cu, Zn, Ni, Mn, Pb, and Hg) and to the absence of organic micro pollutants, coal ash is unlikely to enhance the levels of these contaminants in the soil, in the sugar cane crop or in the groundwater. Laboratory studies had demonstrated that coal and bagasse ash were able to strongly adsorb the herbicides atrazine and hexazinone with a sorption coefficient (km) of 0.13 for atrazine and 0.32 for hexazinone. They would thereby act to decrease the movement of these herbicides to groundwater. Analyses of the soils at the study sites showed that the application of vinasse lowered soil pH from an average of 5.9 to 5.4, but this decrease was only temporary and was not significant enough to affect sugar cane growth. In fact the soil pH returned to its initial value shortly after the application of the 100 m3/ha vinasse. On the other hand, coal ash raised soil pH but this rise in pH was likewise not significant to crop growth. Vinasse and coal ash applied at the high rates of 100 m3/ha and 100 T/ha respectively raised the electrical conductivity of the soil, but in spite of this increase, the electrical conductivity remained below the threshold value of 1700 RS/cm recommended for sugar cane. Furthermore if an application rate of 100 m3/ha of vinasse did increase the organic carbon content of certain soils, it was not observed with coal ash at 100 T/ha. Both vinasse and coal ash improved the level of exchangeable calcium and magnesium in the soils. Thus, 12 months after its application at 100 T/ha coal ash raised the level of exchangeable calcium from 3.40 to 6.61 cmol+/kg in the soil at Pamplemousses, whereas during that same period with vinasse at 100 m3/ha, the level of exchangeable calcium rose only from 1.66 to 1.83 cmol+/kg at Union Park, despite the high K content of the vinasse. Field trials laid down in four different agroclimatic zones provided evidence that increasing application rates of vinasse (25, 50 and 100 m3/ha) did not affect cane or sugar yield. On the contrary, results obtained during the three year study period which covered a plant cane crop and two ratoons, had shown that vinasse gave a higher cane yield (an average of 84.9 T/ha/yr for the four sites) than NPK fertilizers alone (an average of 77.3 T/ha/yr for the four sites). As all the treatment plots received the same rate of N and P, this increase in cane yield was in all probability due to a better K nutrition as well as to an improvement in soil organic matter status brought about by the vinasse. On the other hand, coal ash at 100 T/ha definitely impaired cane yield (an average of 67.5 T/ha/yr for the four sites). When it was applied at 50 T/ha, the effect of coal ash on yield was dependent on soil type, being more severe in the highly leached soils of the super humid region at Belle Rive, and less damaging in the soils having undergone less leaching in the humid region of Pamplemousses. Additionally because of their low heavy metal concentrations, vinasse as well as coal ash did not increase the heavy metal contents in the sugar cane plant. To determine the effects of spreading 100 m3/ha of vinasse and 100 T/ha of bagasse ash on groundwater quality, lysimeter studies were conducted at two sites differing in rainfall regimes (3500 mm/yr at Belle Rive and 1500 mm/yr at Réduit). Drainage water percolating at one metre depth was collected after each heavy rainfall event. Analyses of the leachates showed that the vinasse at 100 m3/ha did not enhance loss of N in the form of nitrate. If, as expected, the heavy metals (Cu, Ni and Zn) known to be mobile had been detected in drainage water, their concentrations remained well below the drinking water limits proposed by the World Health Organization (1 mg/L for Cu, 5 mg/L for Zn and 0.02 mg/L for Ni). Fluorescence quenching studies of the dissolved organic matter in vinasse and of its dialysis fractions with copper confirmed the formation of complexes of the dissolved organic matter with copper. As expected, bagasse ash did not increase the levels of heavy metals and organic micropollutants in the drainage water. But bagasse ash as opposed to vinasse moved significantly more nitrate into the groundwater. In fact the limit of 10 mg/L N-NO3- recommended by World Health Organization for drinking water, was exceeded on many occasions during the study period of November 2005 to February 2008 at both Belle Rive and Réduit lysimeters. To conclude, this study has provided some pertinent and very valuable data. Whereas the disposal of high rates of vinasse on agricultural land under sugar cane is acceptable, the same cannot be stated for coal ash which must be avoided as it is would represent a hazard to the sugar cane crop and to groundwater. Indeed, high application rates of coal ash to sugar cane fields in Mauritius will eventually lead to a decrease in sugar cane productivity and to an increase in nitrate contamination of groundwater

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