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Potencial e disponibilidade de biomassa de cana-de-açúcar na região Centro-Sul do Brasil: uma aplicação de modelos de localização ótima para fins energéticos / Potential and availability of biomass sugarcane in the Center-South region of Brazil: an application of locational models for energy purposesNatália de Campos Trombeta 21 July 2015 (has links)
A busca de segurança energética nos principais centros de consumo vem se estabelecendo como alta prioridade no contexto mundial dado o crescimento da população e da demanda por alimentos e energia. Nacionalmente a matriz energética vincula-se majoritariamente à fonte hídrica fazendo com que, em períodos de escassez pluvial, a segurança energética seja comprometida. Nesse contexto, a energia termelétrica, em especial, a produzida por meio de biomassa de cana-de-açúcar, mostra-se como uma alternativa sustentável ao abastecimento e segurança energética do país. Com isso, o estudo tem por objetivo identificar qualitativa e quantitativamente o potencial e disponibilidade de biomassas de canade- açúcar, bagaço e palha, para uso energético na operação de cogeração e como matéria-prima, a produção de etanol de segunda geração na região Centro-Sul. Para isso foi realizado um levantamento de dados para a safra 2013/14 com 77 usinas visando o desenvolvimento de indicadores agronômicos (quantificação da oferta de bagaço e palha de cana-de-açúcar), tecnológicos (potencial de cogeração do setor) e mercadológicos (preços de energia elétrica, participação nos diferentes ambientes de comercialização). A partir dessas informações foi proposto um modelo matemático visando a maximização do lucro do setor canavieiro avaliado em 4 cenários: 1. Cenário A: base relativa às informações levantadas na pesquisa; 2. Cenário B: considerando-se o aumento do limite de exportação à rede e dos preços de energia aos níveis registrados na safra 2014/15; 3. Cenário C: solicitando a entrada dos principais municípios candidatos das mesorregiões potenciais a instalação de unidades stand alone e; Cenário D: considerando-se parâmetros secundários de investimento e de custos em E2G no curto e médio prazo. Os resultados da pesquisa foram divulgados de forma média para o Brasil e mesorregiões localizadas na região Centro-Sul. De modo geral, os indicadores agronômicos para uma usina típica no Brasil apresentam moagem média de 3 milhões de toneladas de cana, 12% de impureza vegetal e 88% de colheita mecanizada. Tais indicadores proporcionam uma oferta de bagaço e palha ao sistema de aproximadamente 1 milhão de toneladas de biomassa por unidade industrial. Os indicadores tecnológicos no Brasil evidenciaram que 39% das caldeiras amostradas apresentaram tecnologia de baixa pressão de vapor (21 bar), 22% (até 48 bar), 5% (até 65 bar) e 34% (acima de 65 bar). Os turbogeradores amostrados foram de 69% contrapressão simples, 14% contrapressão com extração e 17% condensação. Já para os indicadores mercadológicos verificou-se, para as usinas que exportaram energia, a participação 53% no mercado livre a preços médios de R$ 230,00/MWh e 47% no mercado regulado com precificação de R$ 191,00 MWh. Relativamente aos resultados verificados na modelagem proposta, foi possível avaliar a alocação ótima de biomassa nas mesorregiões e potencial de exportação de energia, etanol celulósico e investimentos de expansão. A partir de tais resultados possibilita-se o direcionamento mais assertivo do planejamento estratégico, de investimentos e de políticas públicas para o aumento da sustentabilidade do setor canavieiro. / The search for energy security in major consumption centers has established itself as a high priority in the global context, given the population growth and the demand for food and energy. Nationally the energy matrix is mainly linked to the water source so that, in periods of rain shortage, energy security is compromised. In this context, the thermoelectric power, in particular, produced by sugarcane biomass, shows up as a sustainable alternative promoting energy security. Thus, the study aims to identify qualitatively and quantitatively the potential and availability of biomass from sugarcane, bagasse and straw for energy use in cogeneration operation and as raw material for second generation ethanol production in South- Center region. For this, it was conducted a data collection for the 2013/14 season with 77 sugarcane mills in order to develop agronomic indicators (measurement of bagasse and straw sugarcane supply), technological indicators (industry cogeneration potential) and market indicators (electricity prices and participation in different marketing environments). From this information it was proposed a mathematical model aimed at maximizing the profit of the sugarcane industry valued at four scenarios: 1. Scenario A: based on the information gathered in the survey; 2. Scenario B: considering increasing the export limit for the network and energy prices to levels recorded in 2014/15 crop; 3. Scenario C: requesting the input of the main potential mesoregions installing stand alone units and; Scenario D: considering other parameters of investment and costs in E2G on the short and medium periods. The survey results were released to Brazil and mesoregions located in the Center-South region. In general, agronomic indicators for a typical sugarcane mill in Brazil have medium crush of 3 million tons of sugarcane, 12% of plant impurity and 88% of mechanized harvesting. These indicators provide a supply of bagasse and straw to the system of approximately 1 million tons of biomass. Technological indicators in Brazil showed that 39% of sampled boiler had a low vapor pressure technology (21 bar), 22% (up to 48 bar), 5% (up to 65 bar) and 34% (over 65 bar). The sampled turbogenerators were 69% simple counter, counter with 14% and 17% extraction condensation. As for the market indicators, for energy exported mills, the share was 53% in the open market at an average price of R$ 230.00 / MWh and it was 47% in the regulated market with pricing R$ 191.00 MWh. In relation to results obtained in the proposed model, it was possible to evaluate the optimal allocation of biomass in mesoregions and energy export potential, cellulosic ethanol and expansion investments. From these results it is possible to propose a more assertive targeting of strategic planning, investment and public policy to increase the sustainability of the sugarcane industry.
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Análise do sistema de espalhamento de palha em colheitadeiras de grãosTolotti, Fabrício Carboni January 2018 (has links)
Este trabalho tem como objetivo analisar a influencia da configuração física do sistema de espalhamento de palha em colheitadeira de grãos na eficiência do espalhamento da palha, visando cobertura mais uniforme do solo de cultivo. Tal processo produzirá melhoramentos no próximo plantio, pois espalhamento mais uniforme de palha evita perdas de nutrientes do solo por incidência luz solar, assim como previne erosão hídrica e eólica. Para analisar a influencia dos parâmetros da configuração física do sistema espalhador de palha foram realizados testes alterando parâmetros como quantidade de pás, ângulo de pás, rotação dos rotores, diâmetro dos rotores, defletor central e vazão de material. Devido à importância econômica no cenário nacional e mundial, utilizou-se a cultura de soja e os testes foram realizados em laboratório seguindo as normas da Sociedade Americana de Engenheiros Agrícolas e Biológicos (ASAE). O trabalho visa fornecer dados que auxiliem designers no desenvolvimento de novos projetos de gerenciamento de resíduos, de modo que venham a aumentar a eficiência desses sistemas, contribuindo com o crescimento da agricultura em no país. Os resultados apontam que a geometria do defletor central apresenta o parâmetro de maior influencia na uniformidade de cobertura da palha ao solo. / The objective of this work is to analyze the influence of the physical configuration of the straw spread system in grain harvester on the efficiency of the straw spread, aiming at a more uniform coverage of the crop soil. This process will produce improvements in the next planting, because more uniform straw spread prevents soil nutrient losses by sunlight, as well as prevent water and wind erosion. In order to analyze the influence of the parameters of the physical configuration of the straw spreader system, tests were performed changing parameters such as blade quantity, blade angle, rotor rotation, rotor diameter, central deflector and material flow. Due to the economic importance in the national and world scenario, the soybean crop was used and the tests were carried out in laboratory according to the standards of the American Society of Agricultural and Biological Engineers (ASAE). The work aims to provide data to assist designers in the development of new waste management projects, so that they will increase the efficiency of these systems, contributing to the growth of agriculture in the country. The results indicate that the geometry of the central baffle presents the parameter of greatest influence on the uniformity of covering of the straw to the soil.
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Využití odpadů z potravinářských výrob / The employment of wastes from food productionHurčíková, Andrea January 2008 (has links)
The waste from agricultural and food industry are accessible in large quantity anywhere in the whole world nowadays. Most of these wastes include cellulose (30 - 40 %), hemicellulose (20 - 40 %) and lignine (10 - 20 %). Therefore these waste materials have wide use as the substrates for the microbial growth and the production of the enzymes. The microorganisms are able to use organic compounds from the wastes as the source of energy for the growth and carbon for synthesis of cellular biomass [24]. Wheat and rice straw are possible to use as the substrates for cultivation of the microorganisms and following production of the enzymes. In this thesis the utilization of the wastes from food industry for the production of the enzymes by the microorganisms was studied. We observed utilization of wheat straw as source of energy for growth of tested microorganisms and investigated their ability for the production of oxidoreductase (laccase). The optimalization of growth conditions of Aureobasidium pullulans was proceeded. Further the activity of laccase was studied. Milled wheat straw was used as the substrate. The cultivation was done in the thermoregulator at the temperature of 27°C. The activity of laccase was not found in this thesis. Petri dishes were contaminated by three unknown microoganisms during optimalization of growth of Aureobasidium pullulans. One of them produced laccase in cultivation with straw.
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Návrh kotle na spalování slámy,sytá pára 143°C 3MW, a pro CZT 6MW / Steam boiler for straw,saturated steam 0,4MPa output 3MW, and for distric heating system 6MWŘezníček, Jan January 2013 (has links)
The work is focused on the design heat generation source in my chosen location. The entire facility should be designed to meet the basic requirements of the client. The primary objective of this work is alternatively propose solutions to perform basic balance calculations and determine the performance of each device. Based on the location selected diagram to produce annual heat needs and recommend the best possible solution.
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Roštový kotel s přirozenou cirkulací na spalování slámy z pšenice,žita a ječmene,20t/h / The Boiler with natural circulation for burning wheat,rye and barley straw,20t/hNěmec, Radim January 2013 (has links)
The aim of this thesis is to propose a grate steam boiler for combustion of straw from wheat, rye and barley output of 20 t / h The calculation is performed by stoichiometric calculation of elemental analysis to calculate the dimensions of a boiler heating surfaces. Default superheated steam can be used mainly for electricity generation.
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Návrh roštového kotle s přirozenou cirkulací na spalování slámy z pšenice,žita a ječmene / Steam boiler with grate firing burning wheat strawKřivák, Petr January 2014 (has links)
The aim of the thesis is the design of the steam grate boilers of 40 t/h for straw burning. The required parameters are generated steam temperature 420 ° C and a pressure of 5.5 MPa. The specified fuel is cereal straw with a calorific value of 9.5 MJ/kg. The calculation is made from the stoichiometric calculation of elemental analysis, to calculate the individual dimensions and heating surfaces of the boiler.
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Impact of type and pretreatment of lignocellulosics on lignin and pulp propertiesRoßberg, Christine 05 April 2016 (has links)
The depletion of fossil fuels and the need to deal with climate change lead to an increasing interest in renewable resources. Lignocellulosic biomass in general, and agricultural residues in particular, could serve as an excellent starting material for the production of cellulose, basic chemicals, lignin and bioethanol in a biorefinery framework as they are abundant, do not compete with food production and are distributed worldwide. Two factors considerably influence the composition and properties of biorefinery products: biomass feedstock and pretreatment process. Their influence on the separability of raw material into a carbohydrate and lignin fraction as well as the composition and properties of these products are objectives of this study. Hereby, the focus is on lignin, as its structure is particularly dependent on the aforementioned factors complicating its further utilisation.
Different agricultural biomass namely barley straw, coconut shell powder, hemp shives, horse manure, maize straw, miscanthus, oat husk, pretreated alfalfa, rape straw, sunflower stalks, tomato stalks and wheat straw were investigated regarding their suitability for lignocellulose separation using alkaline soda pulping. Best separation into a carbohydrate and lignin fraction was achieved for pretreated alfalfa, miscanthus, wheat and barley straw. The purity of the obtained lignin fractions varied in the wide range of 57% klason-lignin content for sunflower stalks and 81% for pretreated alfalfa prior to further purification by dialysis. Lignin fractions were characterised by means of FTIR spectroscopy, elementary analysis, thioacidolysis, size-exclusion-chromatography, thermodesorption, differential scanning calorimetry and different wet chemical methods for determination of functional groups. Lignins could be classified into groups, within which they show similar characteristics: (A) horse manure, rape straw, (B) sunflower stalks, tomato stalks, (C) barley-, maize- and wheat straw and (D) hemp shives, miscanthus. In addition, promising lignin candidates were found for several applications. Thus, by screening different agricultural residues, it is possible to choose a specific raw material, in order to produce lignin with desired properties and functionalities.
The effect of the pretreatment process was studied based on wheat straw. It was subjected to conventional alkaline pulping, microwave-assisted alkaline pulping and organosolv pulping using formic acid and hydrogen peroxide. Pulping parameters were varied in order to attain best possible separation into a carbohydrate and lignin fraction. Of the varied parameters the concentration of both sodium hydroxide and formic acid has the highest impact on yield and purity of the products for alkaline and organosolv pulping, respectively. It additionally influences the content of functional groups of the lignin fraction and is hence, an important parameter for lignin customisation for subsequent utilisation. Furthermore, the possibility of reducing pulping time by using microwave-assisted pulping instead of conventional alkaline pulping is promising, as the obtained carbohydrate fraction has a low intrinsic viscosity, which may enhance enzymatic hydrolysis.
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Environmental and socioeconomic assessment of rice straw conversion to ethanol in Indonesia : The case of BaliSamuel, Victor January 2013 (has links)
The vast rice production in some developing Asian countries like Indonesia raises expectation on poverty alleviation and energy diversification through second generation biofuel production from rice residues, specifically rice straw. This work attempts to estimate the potential environmental and socioeconomic benefits of rice straw-to-ethanol project in Indonesia. Literature research and interviews are performed to quantify several environmental and socioeconomic indicators that are considered as the major concerns inimplementing an energy project. Assuming all the technically available rice straw in Bali is used (~244-415 kilotonne/year), ethanol production may yield gasoline replacement, lifecycle GHG savings, GDP contribution, foreign exchange savings, and employment beneficiaries of 55-93 ML/year, 140-240 millionUSD/year, 19-32 kilotonne of CO2-equivalent/year, 100-180 million USD/year, and 2,200-3,700 persons, respectively. Sensitivity analyses are done for some parameters, showing that ethanol yield, total capital cost, feed-in-tariff for electricity, and imported crude oil price are the major factors affecting the viability of rice straw-to-ethanol project in Indonesia. / Harnessing agricultural feedstock and residues for bioethanol production - towards a sustainable biofuel strategy in Indonesia
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Comparison of Pre- and Post-treatments of Sugarcane Industry By-products to Increase Biomethane ProductionHuang, Baitong January 2020 (has links)
Even though the Brazilian ethanol and sugar production system (based on sugarcane industry) have been providing large amounts of bioenergy, the extensive amounts of organic wastes generated cannot be ignored when it comes to sustainability. Using these biomasses to produce biomethane through anaerobic digestion has been proven as a promising way to tackle this issue. This study investigated the biomethane potential of the co-digestion of these biomasses: SF (sugarcane straw : filter cake = 8:2), SFV (sugarcane straw : filter cake : vinasse = 1:4:45), and D (digestate separated from AD of SFV). Three treatments autoclaving (AU), alkaline (AL) treatment using 6% (w/w) NaOH and the combination of these two (AUAL) were then conducted on SF and SFV as pre-treatments; on D as post- treatments. In the biomethane potential tests of untreated material, the highest methane yield was achieved by SFV with 275.28 ± 11 N ml CH4/g VS, followed by SF with 223.25 ± 10 N ml CH4 g-1 VS, substrate D also resulted in a methane potential of 144.69 ± 2 N ml CH4 g-1 VS. As pre-treatments, AL and AUAL both showed increase in methane yield (between 36.0% and 49.1%) and methane production rate. As post-treatments, AU, AL and AUAL showed distinctive results in methane production, with 33.8%, 99.8% and 128.8% increase, respectively. In comparison with pre-treatment, post-treatment showed a better performance in increasing methane production. The following feeding experiments performed in continuous stirred-tank reactors showed that AL treatment led to an average of 248% increase in methane yield. / Sugarcane waste: towards a zero C emission in the Brazilian bioenergy sector
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Utilization of Poultry Waste (Composted Caged-Layer) as a Supplement for Sheep Fed Straw During Late PregnancyR., Raul Meneses 01 May 1989 (has links)
The utilization of composed caged-layer waste (CCLW) in diets for pregnant ewes fed cereal straw was evaluated. Five sheep were assigned to five diets containing, 0, 5.72, 11.37, 23.80, and 32.69% CCLW in a 5x5 Latin square design. Water intake, feed intake and feces output were measured. Feed and feces were analyzed for dry matter, crude protein, acid detergent fiber (ADF), neutral detergent fiber (NDF), organic matter, hemicellulose and minerals. Thus, nutrient digestibility and nitrogen balance could be calculated. Forty dry, pregnant ewes in the last third of generation were assigned to four dietary treatments contained 0, 11.25, 22.08 and 31.26% CCLW in a complete randomized design. The response measured were ewe weight change, lamb birth weight and wool growth. A ewe surgically fitted with a ruminal cannula was assisted to each treatment. These ewes were adapted to diets for a 7-day period and then ruminal sumples were collected at 0, 3, 9 and 12 hours post-feeding. Connulated ewes were rotated through each treatment pen in a 4x4 Latin square design. Collected samples were analyzed for ph, volatile fatty acids, ammonia and total protozoa. Dry matter and organic matter apparent digestibility decreased as the level of CCLW increased (P<0.08). Other measurements (crude protein, NDF, ADF, hemicellulose and total ash apparent digestibility and nitrogen balance) did not differ between treatments (P<0.05). A biological trend indicated an improvement in structural carbohydrate digestibility as the level of CCLW increased. Ruminal propionic acid concentrations increased as the level of CCLW increased. Ruminal propionic acid concentrations increased as the level of CCLW increased (P<0.05). Ruminal ph and ammonia concentration tended to increase as the level of CCLW increased. These measurements indicated a better ruminal environment for fiber hydrolysis. Daily body weight gain, lamb birth weight and wool growth of ewes did not differ between treatments (P<0.05). The results show that CCLW is a satisfactory source of supplemental nitrogen for gestating ewes.
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