1000 resultados para Produção de carvão vegetal


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Biodiesel is a reality in Brazil, due to the National Program of Biodiesel Production and Use (PNPB), which became mandatory in 2008 in adding 2% biodiesel in all diesel sold in a blend known as B2. The agribusiness sector responded to the federal program, facing many difficulties in biodiesel production, which highlights the supply of raw material. Problems related to biodiesel production were mainly the shortage of vegetable oil, because of demand from domestic and foreign markets, and rising prices of raw materials available for production, making this biofuel production economically feasible, even in Brazil, where agricultural production costs are among the most competitive in the world. The crambe is a specie that has aroused the interest of Brazilian producers due to oil content, hardiness, and mechanized cultivation, mainly for being a winter crop, it becomes one more option for farmers in this period. In addition, you can compose systems of crop rotation as well as being used as ground cover in winter. The aim of this study was to evaluate the potential for productive and cost of production of crambe, conducted in no-tillage system, to compare these parameters with other oil crops such as sunflower, canola and soybean. The trial was conducted in the agricultural year 2008 at the Experimental Farm Lageado belonging to the Faculty of Agronomic Sciences - UNESP, located in Botucatu - SP. The estimated yield was 1.507,05 kg ha-1, resulting in a production of 561,94 liters of oil per hectare. The cost of installation and conduct of crambe per hectare was R$ 875,87, resulting in a cost of R$ 1,56 per liter of oil, the lowest cost among the oilseed crops analyzed.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Agronomia (Agricultura) - FCA

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Pós-graduação em Agronomia (Agricultura) - FCA

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Esta comunicação visa contribuir para o desenvolvimento da agricultura em MPB em Portugal. O estudo abarca uma análise temporal (1994-2014) e da implementação regional das suas principais produções (vegetal e animal). Em Portugal, a agricultura em MPB está concentrada maioritariamente nas regiões do Alentejo, Beira Interior e Trás-os-Montes, tanto em área como em operadores. De facto, em 2014, localizavam-se nestas regiões mais de 85,5% dos criadores de animais e 66,5% dos produtores agrícolas, correspondendo a aproximadamente 84% da área total dedicada à produção em MPB. No referido ano, a produção agrícola ocupava 228 841 hectares, distribuídos por 3 132 produtores, sobretudo pastagens (151 mil ha/1 100 agricultores) e olival (19 mil ha/1 400 agricultores). A produção animal englobava 1 003 produtores, maioritariamente criadores de bovinos (55% dos operadores/73 mil animais) e de ovinos (33% dos operadores/91 mil animais). Os operadores nacionais em MPB apontam como principais entraves à expansão do setor as dificuldades técnicas, designadamente, a obtenção de fatores de produção e o custo dos mesmos e, nas questões comerciais, ligadas à reduzida dimensão do mercado, desorganização da oferta e circuitos de comercialização desajustados, e desconhecimento dos consumidores relativamente ao MPB.

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The present work investigated the potential of different residual lignocellulosic materials generated in rural and urban areas (coconut fibre mature, green coconut shell and mature coconut shell), and vegetable cultivated in inhospitable environments (cactus) aimed at the production of ethanol, being all materials abundant in the Northeast region of Brazil. These materials were submitted to pretreatments with alkaline hydrogen peroxide followed by sodium hydroxide (AHP-SHP), autohydrolysis (AP), hydrothermal catalyzed with sodium hydroxide (HCSHP) and alkali ethanol organosolv (AEOP). These materials pretreated were submitted to enzymatic hydrolysis and strategies of simultaneous saccharification and fermentation (SSF) and saccharification and fermentation semi-simultaneous (SSSF) by Saccharomyces cerevisiae, Zymomonas mobilis and Pichia stipitis. It was also evaluated the presence of inhibitory compounds (hydroxymethylfurfural, furfural, acetic acid, formic acid and levulinic acid) and seawater during the fermentative process. Materials pretreated with AHP-SHP have resulted in delignification of the materials in a range between 54 and 71%, containing between 51.80 and 54.91% of cellulose, between 17.65 and 28.36% of hemicellulose, between 7.99 and 10.12% of lignin. Enzymatic hydrolysis resulted in the conversions in glucose between 68 and 76%. Conversion yields in ethanol using SSF and SSSF for coconut fibre mature pretreated ranged from 0.40 and 0.43 g/g, 0.43 and 0.45 g/g, respectively. Materials pretreated by AP showed yields of solids between 42.92 and 92.74%, containing between 30.65 and 51.61% of cellulose, 21.34 and 41.28% of lignin. Enzymatic hydrolysis resulted in glucose conversions between 84.10 and 92.52%. Proceeds from conversion into ethanol using green coconut shell pretreated, in strategy SSF and SSSF, were between 0.43 and 0.45 g/g. Coconut fibre mature pretreated by HCSHP presented solids yields between 21.64 and 60.52%, with increased in cellulose between 28.40 and 131.20%, reduction of hemicellulose between 43.22 and 69.04% and reduction in lignin between 8.27 and 89.13%. Enzymatic hydrolysis resulted in the conversion in glucose of 90.72%. Ethanol yields using the SSF and SSSF were 0.43 and 0.46 g/g, respectively. Materials pretreated by AEOP showed solid reductions between 10.75 and 43.18%, cellulose increase up to 121.67%, hemicellulose reduction up to 77.09% and lignin reduced up to 78.22%. Enzymatic hydrolysis resulted in the conversion of glucose between 77.54 and 84.27%. Yields conversion into ethanol using the SSF and SSSF with cactus pretreated ranged from 0.41 and 0.44 g/g, 0.43 and 0.46 g/g, respectively. Fermentations carried out in bioreactors resulted in yields and ethanol production form 0.42 and 0.46 g/g and 7.62 and 12.42 g/L, respectively. The inhibitory compounds showed negative synergistic effects in fermentations performed by P. stipitis, Z. mobilis and S. cerevisiae. Formic acid and acetic acid showed most significant effects among the inhibitory compounds, followed by hydroxymethylfurfural, furfural and levulinic acid. Fermentations carried out in culture medium diluted with seawater showed promising results, especially for S. cerevisiae (0.50 g/g) and Z. mobilis (0.49 g/g). The different results obtained in this study indicate that lignocellulosic materials, pretreatments, fermentative processes strategies and the microorganisms studied deserve attention because they are promising and capable of being used in the context of biorefinery, aiming the ethanol production.

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Cactus pear is an important forage for livestock in semi-arid region of Brazil, due to its adaptation to climate conditions in this region, high productivity and nutritional value. The yield of this cactus has positively responded to techniques such as planting density, fertilization and cutting managements, however, in Rio Grande do Norte State, only certain areas have favorable climate conditions to the development of this crop. Drip irrigation, with a small amount of water, has proven to be an alternative to the viability of cactus pear cultivation in these areas. The research aimed to evaluate the effects of different levels of saline water and manure organic fertilization on the morphological characteristics and production of fresh and dry matter of the prickly-pear cactus cv. Miúda (Nopalea cochenillifera Salm Dick) in a dense planting system. The experiment was conducted at the Experimental Station of Terras Secas (EMPARN), Pedro Avelino, latitude 5°31'21" South and longitude 36°23'14" West. The soil was classified as Typical Cambisol Haplicum Carbonate and the water used in irrigation, C4S1T3 (5,25 dS.m-1), with planting spacing of 2.0 x 0.25 m (20,000 plants ha-1). A completely randomized design in a split plot was used, where water levels (0, 7.5, 15.0 and 30.0 mm month-1) with 10 days intervals, were the main plots and organic fertilization (0 , 25 and 50 Mg ha-1 yr-1) the subplots, with four replicates. The measured morphological characteristics were number of cladodes, height and volume of the plant; length, width, perimeter, thickness, area and cladodes area index, fresh and dry matter production, dry matter content, water use efficiency (WUE) and damage promoted by cochineal pest (Diaspis echinocacti) and soft rot (Erwinia carotovora). There was no influence (P>0.05) of organic fertilization on most variables, particularly in relation to the production of fresh and dry matter. The water levels had a significant influence (P<0.05) on most variables, promoting higher height and volume of the plants, larger and thicker cladodes, and increase on fresh and dry matter production (13.55 Mg DM ha-1 yr-1). The absence of irrigation caused a significant expansion in plant damage caused by the cochineal pest and when irrigated with different water levels there was an increase in damage and stand loss, caused by soft rot, been more intense at the higher water level.

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Scientific research in forest production technology area search techniques that increase production per unit area, with high economic viability and reducing environmental impacts. When dealing with forest plantations, studies are needed in the production of biomass and its nutrient content, and these are data parameters for planning the environmental implications of different intensities of forest harvesting. Given the above, this study aimed to elucidate the production and export of biomass and nutrients for two species of the genus Eucalyptus (E. grandis and E. urophylla) grown in the southwestern region of Parana. For this, it was evaluated: the stock of biomass and nutrients in eucalyptus (wood, bark, branches and leaves) at 60 months of age; the export rate of nutrients; the calorific value and economic viability. The biomass and the largest eucalyptus nutrient stocks are predominantly allocated to the stem (wood + bark). The components of biomass showed different chemical compositions, generally being higher in the leaves and bark and lower in wood and branches components. As for the calorific value, the leaves had its calorific value statistically superior than the other fractions, followed by branches, wood and bark. The organic carbon content (C.O.) is directly connected to the calorific value, and the calorific value increases as its content increase. The wood had the highest nutrient use efficiency values, something highly desirable and of great interest to forestry. The leaves showed smaller nutrient utilization efficiency values, with the exception of Ca and Mg that were smaller in the bark, indicating the importance of maintaining these components in the soil after harvest. The wood fraction presents the biomass lower cost when considering the replacement of nutrients exported by its biomass. On the other hand, the leaf fraction showed NPK higher cost of replacement.

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The no-tillage system is the predominant model in the agricultural scenario of southern Brazil. Thus, the use of cover crops is significant due to the addition of biomass to protect the soil surface, and contribute to the cycling and/or fixing of nutrients, and in particular nitrogen (N) with liberation for the subsequent culture. Among the cool season species, it was found predominant use of oat to obtain straw to system. Though large quantities input of residue is not the preferred species to precede the corn, cereal with relevant importance in the Paraná Southwest region. It was aimed to evaluate the productivity capacity of corn in no-tillage, in the absence or presence of nitrogen fertilization, on waste of winter cover crops on soil and climatic conditions of the Paraná Southwest region. The installation of no-tillage was held in 2010 in the experimental area belonging to UTFPR, Campus Dois Vizinhos, on a Red Latosol. For the present study, we used data relating to three agricultural years (2012/2013, 2013/2014 and 2014/2015). The experimental design was randomized block design with split plots with three replications. The main plots consisted of systems composed by cover crops (black oat, ryegrass, rye, turnip, vetch, white lupine, aot+vetch consortium and oat+vetch+turnip), preceding corn. In the subplots were used two doses of nitrogen fertilization (0 and 180 kg ha N) coverage in maize.The biggest coverage rates occurred in the consortium with 95% at 62 days after sowing. The residual effect of 180 kg ha cool season plants following year. The residual effect of 180 kg ha systems, reduced in 21% the C/N ratio of poaceae. The common vetch accumulated 32 kg N per ton of MS added. The oat and rye keeps more than 50% waste to the land cover, after 120 days, while the ryegrass and vetch provide low soil protection. Consortium oat+vetch+turnip, vetch and white lupine, released the largest amounts of N, between 52 and 59 kg ha brassica and consortia positively influencing the diameter and length of cobs, number of kernels per row and, total number of grains per ear of corn, in the absence of mineral N. The weight of a thousand grains was increased by 12.4% by the addition of 180 kg ha increase in productivity of grain by the addition of 180 kg ha N, was 2.1 Mg ha 5.6 Mg ha 6.4 Mg ha components when cultivated on vetch. Systems containing fabaceae, brassica and consortium oat+vetch+turnip, predating the corn, in the absence of mineral N, provided similar grain yelds inrelation to the systems with the addition of 180 kg ha Keywords: Cover crops. No-tillage. Grain yield. Zea mays - 1 -1 N, increased 4.8% coverage rate in the of N in corn/cover crops -1 -1 . Fabaceae, -1 N mineral. The average N, in relation to dose 0 kg ha corn kernels on fabaceae, brassica and consortium oat+vetch+turnip, and poaceae the grains in succession. The consortium added amount between 4.0 the DM in the years of study. There was no effect of mineral N rate for corn yield components when cultivated on vetch. Systems containing fabaceae, brassica and consortium oat+vetch+turnip, predating the corn, in the absence of mineral N, provided similar grain yelds inrelation to the systems with the addition of 180 kg ha-1 N.

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I propose with this paper a reflection on the experiences contained in the creation of the body- in-art (FERRACINI, 2006a, b) that originated the show Rosmaninhos... This process was developed within the coletivo UZUME teatro from João Pessoa PB, through recreations and resignifications of the corporeity and physicality contained in the steps, loas, aboios, songs and choreography observed in the manners that Mestre Zequinha plays in his group of Cavalo Marinho (Sea Horse), resident in the city of Bayeux - PB, and starting from the appropriation of the text Hamlet of William Shakespeare. The body-in-art is understood in this work as a vectorial body that dilates its daily functionality, recognizing a potential learning area capable to generate creative escape lines that destabilize the "subject centered in an individuality and identity" (FOUCAULT apud FERRACINI, 2006b, p.14), being open to the differentiation of itself, indicating the possible existence of an itself-other and of the exchange-in-art space. This process of construction of the body-in-art based on Master Zequinha s ways of playing the Cavalo Marinho was methodically guided by the appropriation of the coletivo UZUME teatro of the stages of Observation, Codification and Theatricalization contained in the technique of corporal mimeses proposed by the LUME Teatro (Campinas - SP). That use resulted in two phases: Active Observation and Composition of the body-in-art. Through the repetition of these aesthetic matrixes of the Cavalo Marinho, the actors discovered actions that when, codified and organized, can configure their body-in-art, which created a vectorial exchange-in-art space to what was found in the Cavalo Marinho party. This search proposed the means of potentiating the actors' work when it comes to a preparation that allowed to dilate the scenic presence and stimulated the production of actions, which culminated in the mounting of the show Rosmaninhos...

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A busca por combustíveis alternativos, tais como os biocombustíveis, torna-se necessária devido à crescente demanda por combustíveis em todos os setores da atividade humana, sendo que quase toda energia consumida no mundo provém do petróleo, uma fonte limitada, que emite grande quantidade de gases poluentes. Devido à grande diversidade de culturas oleoginosas no país, o Brasil demonstra potencial para substituição do diesel pelo biodiesel. No processo de obtenção deste, o óleo vegetal sofre uma transesterificação, sob a ação de um catalisador básico e na presença de um álcool, formando três moléculas de ésteres metílicos ou etílicos de ácidos graxos, que constituem o biodiesel em sua essência, liberando uma molécula de glicerol, que é o coproduto mais abundante desta reação. Sendo assim, a utilização do glicerol residual é uma ótima alternativa para agregar valor à cadeia produtiva do biodiesel, minimizar os danos de um possível descarte inadequado, além de diminuir os custos do processo. Com este intuito, este trabalho propõe o uso do glicerol residual como fonte de carbono para produção de exopolissacarídeos (EPSs). Para tal, foram utilizadas linhagens de bactérias mencionadas na literatura como produtoras de EPSs de importância comercial, sendo elas: Xanthomonas campestris pv. mangiferaeindicae IBSBF 1230, Pseudomonas oleovarans NRRL B-14683, Sphingomonas capsulata NRRL B-4261 e Zymomonas mobilis NRRL B-4286. Os cultivos foram realizados em meio apropriado para cada micro-organismo, e como fontes de carbono foram testadas a sacarose, o glicerol residual e uma mistura de ambos na proporção de 1:1 m/m. Os meios foram inoculados com suspensão da bactéria em estudo, sendo avaliados parâmetros relativos ao crescimento celular e à produção de EPSs. Para X. campestris pv. mangiferaeindicae, foram determinadas algumas propriedades reológicas e térmicas dos EPSs produzidos com as diferentes fontes de carbono, bem como o índice de emulsificação com diferentes óleos vegetais. X. campestris apresentou uma concentração de EPSs em torno de 4 g.L-1 em todos os meios estudados, comportamento similar ao da bactéria P. oleovorans, diferindo apenas no meio contendo sacarose (0,8 g.L-1 ). S. capsulata apresentou uma maior concentração de EPSs em meios contendo sacarose e a mistura de sacarose com glicerol residual, em torno de 3,4 g.L-1 , e em meio contendo glicerol residual este valor caiu para 1,7 g.L-1 . Já Z. mobilis apresentou um melhor resultado em meio contendo sacarose e glicerol residual, atingindo 1,3 g.L-1 , sendo que em meio contendo somente sacarose e glicerol residual estes valores foram inferiores alcançando 0,2 e 0,7 g.L-1 , respectivamente. Quase todas as bactérias atingiram a fase estacionária em 24 h de cultivo e o pH permaneceu praticamente constante, sendo verificada uma queda mais acentuada somente para Z. mobilis. O comportamento reológico foi similar para as xantanas produzidas nos diferentes meios, entretanto a viscosidade inicial foi maior com o meio a sacarose (637 cP), seguido da mistura de sacarose com glicerol residual (279 cP) e glicerol residual (60 cP). O IE24 foi superior quando utilizado o óleo de milho, atingindo valores de 97, 72 e 64 % em sacarose, mistura de sacarose com glicerol e glicerol residual, respectivamente. Desta forma, pode-se afirmar que a mudança na fonte de carbono afeta estas propriedades.

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A maior parte da energia hoje consumida no mundo é derivada de fontes como petróleo, carvão e gás natural. Essas fontes, no entanto, não são renováveis e podem se esgotar em data futura. Nas últimas décadas, as fontes renováveis de combustíveis de base biológica, em especial o bioetanol, têm sido consideradas como alternativa à matriz energética convencional. Porém, existe a necessidade de ampliação da oferta de matérias-primas para produção de etanol, sem pressionar a área plantada para produção de alimentos, o que tem levado empresas e países a investirem em pesquisas para maior utilização de outras matériasprimas. As microalgas surgem como uma das alternativas mais promissoras para a produção de bioetanol, sendo que modificações nas condições de cultivo podem propiciar incremento na concentração de carboidratos destas. Neste contexto, o objetivo deste trabalho foi avaliar a influência da concentração de nutrientes na concentração de carboidratos de microalgas e produzir bioetanol a partir destas. Avaliou-se a síntese de carboidratos das microalgas Chlorella homosphaera e Spirulina platensis LEB 52 em cultivos mixotróficos com diferentes concentrações do componente nitrogenado e cloreto de sódio adicionados aos meios de cultivo. Para a microalga Chlorella minutissima, foram avaliados os efeitos do meio de cultivo e das concentrações dos componentes nitrogenado e fosfatados utilizados no meio de cultivo da microalga sobre a concentração de carboidratos desta. Foram realizadas fermentações alcoólicas utilizando como substrato biomassa das microalgas Chlorella pyrenoidosa e Spirulina sp. LEB 18 acrescidos de glicose e sacarose. Para a microalga Chlorella homosphaera, a maior produtividade em carboidratos foi obtida nos ensaios realizados com a maior concentração de KNO3 com menor concentração de NaCl e menor concentração de KNO3 com maior concentração de NaCl (0,014±0,001 g.L-1 .d-1 e 0,015±0,002 g.L-1 .d-1 , respectivamente). A maior produtividade em carboidratos nos cultivos de Spirulina platensis LEB 52 (0,116±0,002 g.L-1 .d-1 ) foi verificada no experimento no qual a microalga foi cultivada nas menores concentrações de NaNO3 e NaCl. A microalga Spirulina platensis LEB 52 apresentou maior produtividade em carboidratos quando comparada à microalga Chlorella homosphaera. A microalga Chlorella minutissima cultivada em meio Basal, com adição de 0,125 g.L-1 do componente nitrogenado (KNO3) e sem adição dos componentes fosfatados (K2HPO4 e KH2PO4) apresentou a maior produtividade em carboidratos nos cultivos (0,030±0,002 g.L-1 .d-1 ). O ensaio com biomassa de Spirulina sp. LEB 18 com adição de glicose apresentou eficiência superior na formação de etanol e produtividade em etanol (68,487±2,592% e 1,182±0,051g.L-1 .h-1 , respectivamente).

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A espécie Spondias tuberosa Arr. Cam. (umbuzeiro) destaca-se como uma das espécies arbóreas de maior potencial do semiárido brasileiro. Apesar de sua relevante importância socioeconômica e ambiental, há falta de estudos voltados para o estabelecimento de um modelo de produção de mudas da espécie. O objetivo desse trabalho foi avaliar a produção de mudas de Spondias tuberosa utilizando diferentes substratos e tamanho de recipientes. O experimento foi conduzido no viveiro do Laboratório de Ecologia Vegetal (LEV) do Centro de Ciências Agrárias (CCA) da Universidade Federal da Paraíba (UFPB), Areia - PB. O delineamento experimental usado foi em blocos casualizados em esquema fatorial 2 x 7 e parcelas subdivididas, sendo que os recipientes representaram as parcelas e os substratos as subparcelas. Foram utilizados substratos formulados a partir da mistura de terra de subsolo (37,5-100%), areia lavada (12,5- 25%) e esterco bovino curtido (10-50%). Os recipientes utilizados foram sacos de polietileno preto com volumes de 1900 cm3 (15 x 27 cm) e 5000 cm3 (25 x 26 cm). Para a obtenção das plântulas, sementes de Spondias tuberosa foram semeadas em sementeira de alvenaria até a repicagem (90 dias após o semeio). Aos 78 dias, após a repicagem, as mudas foram avaliadas quanto à altura, diâmetro do colo, relação altura/ diâmetro do colo, diâmetro do xilopódio, comprimento de raiz, massa seca da parte aérea e raiz. Os dados obtidos foram submetidos à análise de variância e ao teste F, sendo as médias comparadas pelo teste de Tukey ao nível de 5% de probabilidade, utilizando o software SISVAR®. Os substratos com esterco bovino curtido proporcionaram os maiores valores em altura e comprimento de raiz. Para a produção de mudas de Spondias tuberosa, é recomendado o substrato contendo terra de subsolo (45%) + Areia (15%) + Esterco bovino (40%).