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Fate of nitrogen/trace metals species during combustion and gasification of biomassPetrolati, Andrea January 2010 (has links)
This thesis focused on the fate of nitrogen and trace metals species from combustion and gasification of biomass. The effect of process parameters on the release of these species during pilot-scale combustion and gasification of biomass was investigated and the information used to identify methods for the reduction of these species. The investigation focused on Miscanthus and Dried distillers’ grains with solubles (DDGS). The pilot-scale test rigs used were a fluidised-bed combustor and a fixed-bed downdraft gasifier. The two fuels were analysed by means of proximate, ultimate and ash analysis. The process parameters monitored were temperatures, gas flow, gas composition and ash composition and the process parameters studied are bed temperature and equivalence ratio. The different nitrogen content of the two fuels plays an important role in the emission. Both bed temperature and air to fuel ratio have demonstrated to have an important influence in the release of nitrogen oxides in combustion and ammonia in gasification, therefore they can be used to mitigate the emission of these species in the flue gas. Both processes are affected by the high alkali metals content of the fuels for the tendency to form low melting composites. Differences have been highlighted in the metal distribution between combustion and gasification. The different nitrogen and ash content of the two fuels make the results of the present thesis applicable to predict the behaviour of other biomass fuels according to the fuel characteristics. The scale of the tests performed allowed highlighting which methods can be used to control the emission of nitrogen and trace metal species. Moreover, the investigation highlighted major drawbacks in the use of biomass fuels in both fluidised bed and fixed bed technology due to ash properties.
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Effect of graded levels of wheat-based dried distiller's grains in a barley ration on the growth performance, carcass quality and rumen characteristics of feedlot steersBeliveau, Renee Maxine 10 September 2008
Two trials were conducted to evaluate the effects of titrated levels of wheat-based dried distillers grains on feedlot performance, carcass characteristics and rumen fermentation parameters of cattle fed wheat-based dried distillers grains with solubles (DDGS). In trial 1, a barley grain-based diet (0% DDGS) was used as a control. It was formulated to 12% CP and 1.52 and 0.93 Mcal kg-1 net energy of maintenance (NEm ) and net energy of gain( NEg) respectively, during the backgrounding period and to 13% crude protein (CP) and 1.90 and 1.26 Mcal kg-1 NEm and NEg respectively, during finishing. Wheat-based DDGS replaced on a dry matter basis (DM) barley grain at levels of 8, 16, 24 and 32% during backgrounding and 6, 12, 18 and 23% during finishing. During backgrounding dry matter intake (P = 0.02), ADG (P = 0.04), and ultrasounded (US) longissimus. dorsi gain (P = 0.02) exhibited a cubic response to DDGS inclusion level with theoretical minima at 6.9, 8.1 and 6.9% DDGS respectively, and theoretical maxima responses at 27.2, 30.8 and 23.9% DDGS, respectively. Feed efficiency exhibited a quadratic response (P = 0.02) to DDGS inclusion level with a theoretical poorest response at 13.1% DDGS. Similar responses were noted during the first 56 d of the finishing period, however over the course of the finishing period no effect of DDGS inclusion level was noted on average daily gain (ADG), DMI, feed efficiency (FE), ultrasound measurements or on any carcass traits. <p>Trial 2 examined the effects of graded levels of wheat-based DDGS (0, 7, 14, 21% DM basis) on rumen fermentation characteristics using rumen cannulated heifers. Rumen pH measurements indicated that the pH mean at or below 5.8 and 5.5 decreased as DDGS inclusion level increased to 14% DM. The highest values (P<0.05) for pH area between the benchmarks of 5.5 and 5.2, pH area below 5.2 and time below pH 5.2 were found at the 14% DDGS inclusion level, pointing to rumen fermentation characteristics associated with severe rumen acidosis. Ammonia nitrogen levels, percent acetate, percent butyrate and the acetate: propionate ratio increased linearly (P < 0.0001) with DDGS. Propionate concentration decreased linearly (P = 0.006) as the level of DDGS increased. In situ rumen degradation kinetics showed that the DM and CP soluble fraction of DDGS to be significantly higher than that of rolled barley, however effective degradability of dry matter (EDDM) and effective degradability of crude protein (EDCP) were greater for barley.
The results of this trial indicate that wheat-based DDGS has an energy value at least equal to that of barley grain with no adverse effects on cattle performance or carcass quality. Furthermore, since all treatments showed equal susceptibility to sub-acute ruminal acidosis (SARA) and therefore, wheat-based DDGS as a dietary ingredient is unable to mitigate rumen fermentation conditions associated with SARA.
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Effect of graded levels of wheat-based dried distiller's grains in a barley ration on the growth performance, carcass quality and rumen characteristics of feedlot steersBeliveau, Renee Maxine 10 September 2008 (has links)
Two trials were conducted to evaluate the effects of titrated levels of wheat-based dried distillers grains on feedlot performance, carcass characteristics and rumen fermentation parameters of cattle fed wheat-based dried distillers grains with solubles (DDGS). In trial 1, a barley grain-based diet (0% DDGS) was used as a control. It was formulated to 12% CP and 1.52 and 0.93 Mcal kg-1 net energy of maintenance (NEm ) and net energy of gain( NEg) respectively, during the backgrounding period and to 13% crude protein (CP) and 1.90 and 1.26 Mcal kg-1 NEm and NEg respectively, during finishing. Wheat-based DDGS replaced on a dry matter basis (DM) barley grain at levels of 8, 16, 24 and 32% during backgrounding and 6, 12, 18 and 23% during finishing. During backgrounding dry matter intake (P = 0.02), ADG (P = 0.04), and ultrasounded (US) longissimus. dorsi gain (P = 0.02) exhibited a cubic response to DDGS inclusion level with theoretical minima at 6.9, 8.1 and 6.9% DDGS respectively, and theoretical maxima responses at 27.2, 30.8 and 23.9% DDGS, respectively. Feed efficiency exhibited a quadratic response (P = 0.02) to DDGS inclusion level with a theoretical poorest response at 13.1% DDGS. Similar responses were noted during the first 56 d of the finishing period, however over the course of the finishing period no effect of DDGS inclusion level was noted on average daily gain (ADG), DMI, feed efficiency (FE), ultrasound measurements or on any carcass traits. <p>Trial 2 examined the effects of graded levels of wheat-based DDGS (0, 7, 14, 21% DM basis) on rumen fermentation characteristics using rumen cannulated heifers. Rumen pH measurements indicated that the pH mean at or below 5.8 and 5.5 decreased as DDGS inclusion level increased to 14% DM. The highest values (P<0.05) for pH area between the benchmarks of 5.5 and 5.2, pH area below 5.2 and time below pH 5.2 were found at the 14% DDGS inclusion level, pointing to rumen fermentation characteristics associated with severe rumen acidosis. Ammonia nitrogen levels, percent acetate, percent butyrate and the acetate: propionate ratio increased linearly (P < 0.0001) with DDGS. Propionate concentration decreased linearly (P = 0.006) as the level of DDGS increased. In situ rumen degradation kinetics showed that the DM and CP soluble fraction of DDGS to be significantly higher than that of rolled barley, however effective degradability of dry matter (EDDM) and effective degradability of crude protein (EDCP) were greater for barley.
The results of this trial indicate that wheat-based DDGS has an energy value at least equal to that of barley grain with no adverse effects on cattle performance or carcass quality. Furthermore, since all treatments showed equal susceptibility to sub-acute ruminal acidosis (SARA) and therefore, wheat-based DDGS as a dietary ingredient is unable to mitigate rumen fermentation conditions associated with SARA.
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Retrofitting analysis on first generation ethanol productionVathsava Rajoli, Sree January 2015 (has links)
First generation bioethanol generated from feedstocks is a sustainable alternative to fossil fuels, and the demand for fuel ethanol has promoted studies on the use of the grain as feedstock. This thesis describes various process designs and the economic feasibility for producing the main product ethanol and other by-products such as Biogas and DDGS (Distillers Dried Grains with Solubles) from the grain. The techno-economic analysis was performed by the data provided by Agroetanol industry, located in Norrköping, Sweden. The key target of this simulation work was to evaluate the influence of several process designs and the main production factors on the ethanol production process, in terms of energy efficiency, ethanol production cost and plant profitability. The main aim of this work was to simulate the current industrial process and to develop novel alternative retrofits by integrating new technologies and for investigating the effects on the plant profitability. In the base case, the cost sensitivity analysis was carried out on the grain buying price, ethanol and DDGS selling price. Along with the cost sensitivity analysis, the capacity sensitivity analysis was performed on the base case model to check the influence of different capacities on the plant profitability. While coming to the study of developing alternative retrofits, the three retrofits were developed on the base case process and they are as following: Retrofit 1) modifying the distillation and dehydration section of the base case retrofit (current process in Agroetanol), Retrofit 2) checking the impact of ethanol concentration on technical and economic aspects of the plant and Retrofit 3) installing the biogas digester.The modelling effort resulted in developing the base case model with an ethanol production rate of 41,985 ton/ year. The capital cost of the base case process was calculated to be at 68.85 million USD and the aspen economic analyzer calculated the product value of the ethanol and DDGS as 0.87 USD/litre and 0.37 USD/kg, respectively. Through cost sensitivity analysis results, it is identified that the ethanol selling price and the grain buying price have significant effects on the plant economy and it is confirmed that they are the main factors playing on the plant profitability in the base case model.The results of the alternative retrofits clearly demonstrate the importance of higher ethanol tolerant strains in ethanol production, which showed a less payback period compared to the base case. The payback periods of all the cases are showing the following patterns from the least to the highest: Retrofit 2 (17%) > Base case > Retrofit 3 > Retrofit 2 (4%) > Retrofit 1.Further retrofitting analysis results also suggested that using the stillage for biogas production will help in reducing the energy costs of the plant. The energy consumption of all the retrofits in ascending manner is as follows: Retrofit 3 > Retrofit 2 (17%) > Base case > Retrofit 1 > Retrofit 2 (4%). The energy usage result comparison of all the cases shows that, in third retrofit the overall energy consumption is decreased by 40% than the base case model.
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"Utilização de grãos secos de destilaria com solúveis (DDGS) de milho na alimentação de vacas em lactação"Werle, Caroline Hoscheid 24 February 2017 (has links)
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Previous issue date: 2017-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The objective of this study was to evaluate the best level of DDGSinclusion in the diet of lactating cows. For this purpose, five lactating Dutch cows distributed in a 5x5 Latin square were used, fed diets containing 0%, 8%, 16%, 24% and 32% inclusion levels of DDGS in DM. The parameters evaluated were dry matter and nutrient intake and digestibility, microbial synthesis, milk production and composition, blood parameters and economic viability. The data were submitted to analysis of variance and polynomial regression considering the inclusion levels of DDGS at the 5% probability level. Thus, a reduction in the dry matter intake, organic matter, crude protein and nonfibrous carbohydrates and an increase in the intake of ethereal extract, neutral detergent fiber and total digestible nutrients were observed. The animals' body condition score was not altered despite the reduction of body weight to inclusion levels. The digestibilities of crude protein, neutral detergent fiber, total carbohydrates and total digestible nutrients increased linearly with inclusion of the coproduct in the diet. Dry matter digestibility was reduced according to the inclusion levels. Milk production was not influenced by DDGS inclusion levels. There was no change in allantoin excretions and in the production of microbial protein per kilogram of total digestible nutrients. Fasting plasma cholesterol levels at four hours after feeding presented a linear increasingeffect due to the fat content in the coproduct composition. The fasting creatinine content was reduced with increasing inclusion levels. The economic return was higher for the levels with inclusion of the coproduct in the diet. Thus, the use of DDGS in the feeding of lactating cows can be performed up to the 32%. / Objetivouse avaliar o nível de inclusão do DDGS na dieta de vacas em lactação. Foram utilizadas cinco vacas holandês em lactação, distribuídas em um quadrado latino 5x5, alimentadas com dietas contendo níveis de 0%, 8%, 16%, 24% e 32% de inclusão de DDGS na MS. Os parâmetros avaliados foram ingestão e digestibilidade da matéria seca e dos nutrientes, síntese microbiana, produção e composição do leite, parâmetros sanguíneos e viabilidade econômica. Os dados foram submetidos à análise de variância e regressão polinomial considerando os níveis de inclusão de DDGS ao nível de 5% de probabilidade. Desta forma, observouse redução na ingestão de matéria seca, matéria orgânica, proteína bruta e carboidratos não fibrosos e aumento na ingestão de extrato etéreo, fibra em detergente neutro e nutrientes digestíveis totais. O escore de condição corporal dos animais não foi alterado apesar de ocorrer a redução do peso corporal para os níveis de inclusão.Asdigestibilidades da proteína bruta, fibra em detergente neutro, carboidratos totais e dos nutrientes digestíveis totais aumentaram linearmente com a inclusão do coproduto na dieta. Já a digestibilidade da matéria seca reduziu conforme os níveis de inclusão. A produção de leite não foi influenciada pelos níveis de inclusão de DDGS. Não houve alteração para as excreções de alantoínae para a produção de proteína microbiana por quilograma de nutrientes digestíveis totais. Os teores de colesterol plasmático em jejum e quatro horas após a alimentação apresentaram efeito linear crescente devido ao teor de gordura na composição do coproduto. O teor de creatinina em jejum apresentou redução com o aumento dos níveis de inclusão. O retorno econômico foi maior para os níveis com inclusão do coproduto na dieta. Desse modo, a utilização de DDGS na alimentação de vacas em lactação pode ser realizada até o nível de 32% de inclusão.
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Evaluation of Feeding Varying Levels of Digestible Lysine on Broiler Breeder Male Reproductive Characteristics and Body Weight ChangesObi, Chinwendu Nkechi 15 December 2012 (has links)
A preliminary test was conducted evaluating the effect of digestible lysine (dLys) on broiler breeder (BB) male semen quality from forty-one to forty-nine wk of age. Five dietary treatments: corn-soybean meal diet with 1,000 mg dLys/rooser/day (Soy1,000), distillers dried grains with solubles diet with 1,000 (DDGS1,000), 850 (DDGS850), 700 (DDGS700), and 550 (DDGS550) mg dLys/rooster/day. Semen quality was similar except percentage dead sperm which was higher in DDGS550. A second trail was conducted using the same dietary treatments as the preliminary test during twenty to thirty-nine wk of age. Semen quality was similar except percentage dead sperm which was higher in Soy1,000. Soy1,000 exhibited higher body weight (BW), breast weight, and plasma testosterone. In conclusion dLys levels from 1,000 to 700 mg/rooster/day will not adversely affect semen quality of BB males. Attention should be given to BW in BB as it could lead to an increased percentage dead sperm.
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An Applied Investigation of Corn-Based Distillers Dried Grains with Solubles in the Production of Natural Fiber-Plastic CompositesCastillo, Hugo Eudosio 12 May 2012 (has links)
The main objective of this research was to examine uses for distillers dried grains with solubles (DDGS), a coproduct of ethanol production plant, in the fiber-reinforced plastic composites industry. Initially the effort intended to take advantage of the DDGS components, using chemical reactions, to produce coupling agents to improve the physical properties of the composite. Four different chemicals plus water were used to convert proteins into soluble amino acids. The results were not as expected, and appeared to show an early pyrolysis of DDGS components. This may be due to regeneration of proteins when pH of solutions is neutralized. Procedures were then investigated to utilize DDGS for different markets. Considering that oils and proteins of DDGS can thermally decompose, it seemed important to separate the major components and work with DDGS fiber alone. A procedure to extract oil from DDGS using ethanol and then to hydrolyze proteins with ethanol diluted with water, acid and sodium sulfite, was developed. The resulting DDGS fiber or residual material, with a low content of oil and proteins, was used as filler in a propylene matrix with a lubricant and coupling agent to make natural fiber plastic composites (NFPC). Composites containing wood flour (WPC) were prepared simultaneously with those of DDGS fiber to compare tensile properties and fracture surfaces of the specimens by scanning electron microscope (SEM). This study demonstrates that DDGS fiber can replace wood fiber as a filler in NFPC.
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Alteration to Gastrointestinal Microbial Communities Associated with Increasing Fiber DigestibilityKlotz, Courtney Elizabeth 04 September 2013 (has links)
Distillers dried grains with solubles (DDGS) is a byproduct of distillation. Its increased availability has led to research into overcoming the nutritional limitations of its high non-starch polysaccharide (NSP) content for use in monogastric animal feed. The purpose of this study was to examine the effects of two factors (the inclusion of DDGS and/or inclusion of a carbohydrase mixture) on the richness and abundance of swine gastrointestinal bacteria. The carbohydrase mixture was expected to aid digestion, leading to increased nutritional availability for the host while simultaneously shifting dominant communities within the gut microbiome.
Ileal cannulated pigs (n = 8, BW = 64.3 +/-0.5 kg) were allotted to 4 dietary treatments in a replicated 4 x 4 Latin square design. Treatments resulted in changes to bacterial richness, and diets containing DDGS increased the 16S rDNA abundance of members of Bacteroides (P < 0.0001), Ruminococcus (P < 0.0001), the Clostridium coccoides group (P <0.0001), and the Clostridium leptum subgroup (P = 0.005). Significant interactions between diet and carbohydrases were determined for total bacteria in the ileal digesta (P = 0.01) and feces (P = 0.02), Bacteroides (P = 0.003), and the Clostrdium leptum subgroup (P = 0.03). The DDGS diet with the inclusion of the carbohydrases was able to maintain, or increase the abundance of fiber degrading bacteria while theoretically increasing nutrition for the host. / Master of Science in Life Sciences
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Desempenho produtivo e reprodutivo de Lambaris-de-rabo-amarelo (Astyanax altiparanae) alimentados com dietas contendo diferentes níveis de grãos secos de destilaria com solúveis (DDGS) / Productive and reproductive performance of lambari (Astyanax altiparanae) fed diets containing distillers dried grains with solubles (DDGS)Zimba, Rosa Dulce 17 May 2016 (has links)
Grãos secos de destilaria com solúveis (DDGS) são uma fonte alternativa protéica e energética, de baixo custo se comparado com a farinha de peixe e o farelo de soja. Neste estudo avaliou-se a influência dos diferentes níveis de DDGS no desempenho produtivo e reprodutivo de lambari-de-rabo amarelo, bem como analisou-se a viabilidade econômica deste produto. O delineamento experimental foi inteiramente casualizado composto de 4 tratamentos (níveis de DDGS) e 4 repetições. Foram elaboradas dietas contendo 0%, 10%, 20% e 30%, de DDGS em substituição parcial e total do farelo de soja e quirera de arroz. Um total de 2400 alevinos de lambari foram estocados em 16 tanques de 500L, contendo biofiltro e um sistema individual de recirculação de água, à densidade de 0,3 peixes/ L. Os peixes foram alimentados 4 vezes ao dia no primeiro mês e 2 vezes nos meses subsequentes durante 150 dias, à taxa diária do arraçoamento de 5% de peso vivo. Mensalmente os peixes foram pesados e no final determinou-se os parâmetros produtivos tais como: ganho de peso, índice de conversão alimentar, taxa de sobrevivência, taxa de crescimento específico, taxa de eficiência protéica, índice de crescimento instantâneo, taxa de ganho de peso, fator de condição corporal e composição química do corpo inteiro e do músculo. Após o período de alimentação foram determinados os seguintes parâmetros reprodutivos: índice gonadossomático, volume dos ovos, fertilidade inicial, fertilidade inicial relativa, taxa de fertilidade, índice de desova, fertilidade final, fertilidade final relativa, taxa de eclosão e sobrevivência, diâmetro dos ovos e do vitelo e comprimento das larvas. Foi feita a histologia das gônadas das fêmeas e dos machos e avaliação do sêmen. Também se analisou a viabilidade do uso do DDGS. Os dados foram submetidos à análise de variância (α = 0,05), à regressão e teste de tendência, e para a comparação das médias de viabilidade económica utilizou-se o teste Tukey por meio do programa SAS. A adição de DDGS não afetou os parâmetros produtivos (P > 0,05), exceto para a matéria mineral do músculo (P < 0,05). Ocorreram diferenças (P < 0,05) para fertilidade inicial, peso, comprimento total e padrão dos machos. Histologicamente não se evidenciou diferenças entre as estruturas morfológicas dos ovários, nos testículos dos peixes alimentados com dieta de 30% de DDGS apresentaram células espermáticas abundantes, portanto o desenvolvimento gonadal não foi influenciado negativamente pelo DDGS. Economicamente as dietas contendo DDGS (10, 20 e 30%) foram respetivamente 2; 7 e 11% menos onerosas do que a dieta com farelo de soja e quirera de arroz. As médias do custo do ganho não diferiram (P > 0,05) entre si, indicando que se pode substituir o farelo de soja e quirera de arroz com o DDGS sem grandes prejuízos no desempenho e a baixo custo de alimentação. / Distillers dried grains with solubles (DDGS) is a protein and energy source alternative, is used to formulate diets to feed fishes in replecement of fish meal and soya, and the cost is low. This research was carried out to investigate the influence of dietary inclusion of DDGS levels on growth and reprodution performance and evaluate its economical value of lambari. The experimental delineament were four isonitrogenous diets were formulated that contain 0%, 10%, 20%, and 30% of DDGS in substituation of soja meal and broken rice. A total of 2400 lambari were stored in 16 tanks 500L, provided with a biofilter and a single system of water recirculation, density were 0,3 fish / L. During 150 days the groups of fish were fed with experimental diets until visual satiety four times per day for the first month and twice in the remaining months, the daily rate of feeding were 5% of body weight. Each month the fish were weighed for determination of production parameters such as: weight gain, feed conversion rate, survival rate, specific growth rate, protein efficiency ratio, instantaneous growth rate, weight gain rate, condition factor physical and chemical composition of the whole body and muscle. After the feeding period terminated reproductive parameters such as: gonadossomatic index, egg volume, initial fertility, relative initial fertility, fertility rate, spawning rate, final fertility, final relative fertility, hatching and survival rate, diameter of eggs and length of the larvae. It was made the histology of the gonads (females and males) and semen evaluation. Also analyzed the economic viability of using DDGS in the diets. The data were subjected to ANOVA, regression and trend test, economical value analised by Turkey test (α = 0,05). Addition of DDGS did not affect the productive parameters (P > 0,05) except for the mineral of muscle (P < 0,05). There were differences (P < 0,05) in initial fertility (FI), weight, total and pattern length of males. Histologically no detectable morphological differences between the structures of the ovaries, but testes of fish fed with diet of 30% DDGS showed abundant sperm cells, therefore gonadal development was not negatively influenced by the DDGS. Economically diets containing DDGS (10, 20 and 30%) were respectively 2; 7:11% cheaper than the diet with soy meal and broken rice. The cost gain was no significant (P > 0.05). The result from this resarch shows that DDGS can replace soybean meal and broken rice without major losses in performance and low cost supply.
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Síntese de nanotubos de carbono a partir do reaproveitamento de resíduos sólidos carbonosos. / Synthesis of carbon nanotubes from the recovery of carbonaceous solid wastes.Alves, Joner Oliveira 23 August 2011 (has links)
A disposição de resíduos sólidos é um dos temas mais discutidos na atualidade. A queima controlada dos resíduos possibilita a redução do volume a ser depositado e a geração de energia. Este trabalho estudou o emprego de uma nova tecnologia no atual processo de queima de uma série de resíduos carbonosos. Um sistema de catálise foi utilizado para sintetizar nanotubos de carbono (CNTs) a partir dos gases gerados pela pirólise/combustão dos resíduos. Os CNTs são materiais com alto valor de mercado devido às suas excepcionais propriedades. Foram alvos de estudo os resíduos da indústria do etanol (bagaço da cana-de-açúcar e grãos secos de destilaria com solúveis - DDGS), borracha de pneus inservíveis e garrafas de poli(tereftalato de etileno) pós-consumo. Amostras dos resíduos foram incineradas em um forno de fluxo contínuo com atmosfera controlada através da injeção de N2 e temperaturas de 600-1000°C, sendo que jatos de O2 foram adicionados em alguns experimentos. O efluente gasoso da queima foi submetido a um filtro de SiC e repassado a um segundo forno com temperatura constante de 1000°C. Telas de aço inoxidável foram dispostas no forno secundário para atuarem como catalisador. A cromatografia gasosa foi utilizada para a comparação dos efluentes com e sem o uso do catalisador, sendo constatado que o emprego das telas ocasionou uma significativa redução na emissão de poluentes. Após os experimentos, foi verificada a formação de partículas de carbono sólido na superfície do catalisador. As partículas formadas foram submetidas a análises por MEV, MET, TG e Raman. Os resultados apontaram a formação de nanotubos de carbono de parede múltiplas com comprimentos de 20 a 50 µm e diâmetros entre 20 e 50 nm quando empregados pneus e bagaço da cana como matérias-primas. Experimentos que empregaram DDGS e garrafas PET produziram microfibras de carbono com comprimentos em torno de 40 µm e diâmetros entre 80 e 200 nm. / The disposal of solid wastes is one of the most discussed topics nowadays. Controlled burning allows the reduction of waste volumes to be deposited, and the energy generation. This study examined the use of a new technology in the current burn processes of several carbonaceous wastes. A catalyst system was used to synthesize carbon nanotubes (CNTs) from the gases generated by pyrolysis/combustion of wastes. CNTs are materials with high market value due to its exceptional properties. Residues of the ethanol industry (sugarcane bagasse and distillers dried grains with solubles - DDGS), scrap tire rubbers and post-consumer polyethylene terephthalate bottles were subject of study. Waste samples were incinerated in a laminar-flow furnace with controlled atmosphere by injection of N2, and temperatures of 600-1000°C, while jets of O2 were added in some experiments. The effluent gases were subjected to a SiC filter and channeled into the second furnace with constant temperature of 1000°C. Stainless steel meshes were placed in the second furnace in order to work as catalyst. Gas chromatography was used to compare the effluent with and without the catalyst use, wherein was showed that the use of meshes caused a significant reduction in the emissions. After the experiments, the formation of solid carbon particles was verified on the catalyst surface. The formed particles were analyzed by SEM, TEM, TG and Raman. Results showed the formation of multi-wall carbon nanotubes with lengths of 20-50 µm and diameters in the range of 20-50 nm when tires and sugarcane bagasse were used as raw materials. Experiments using DDGS and PET bottles produced carbon microfibers with lengths of about 40 µm and diameters of 80-200 nm.
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