FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Nesta pesquisa, objetivou-se avaliar o processo de compostagem utilizando-se matÃria orgÃnica disponÃvel no banco de mudas da cidade de Sobral - CE, (esterco eqÃino e palhas de carnaÃba) em trÃs sistemas de aeraÃÃo: com injeÃÃo de ar, sucÃÃo de ar e injeÃÃo e sucÃÃo ar em ciclo (hÃbrido), observando-se os parÃmetros recomendados pela legislaÃÃo brasileira vigente, durante as fases de degradaÃÃo ativa e de maturaÃÃo. O experimento foi instalado com trÃs tratamentos, sendo um (01) sob o modo positivo; um (01) sob o modo negativo e um (01) sob o modo hÃbrido, obedecendo as proporÃÃes de 30% de esterco eqÃino e 70% de palhas, para todos os tratamentos. Cada tratamento foi repetido 3 (trÃs) vezes, perfazendo, assim, um total de 9 (nove) parcelas. Foi realizada a avaliaÃÃo destes processos, tendo sido observadas, principalmente, a influÃncia da aeraÃÃo e da umidade no desempenho destas tÃcnicas de tratamento, em leiras estÃticas aeradas. Durante a fase ativa, as leiras sob o modo positivo apresentaram reduÃÃo mÃdia de matÃria orgÃnica de 26,55%, as leiras sob o modo negativo de 21,78%, enquanto que as leiras, sob o modo hÃbrido de 31,21%. Durante a fase de maturaÃÃo, foram reviradas trÃs leiras de cada sistema de aeraÃÃo. A reduÃÃo mÃdia da matÃria orgÃnica das mesmas foi de 50,63%, em 50 dias; as demais apresentaram reduÃÃo mÃdia de 39,54%, em 60 dias. Durante a fase ativa, as leiras operadas sob o modo positivo apresentaram, em mÃdia, reduÃÃo de Carbono de 26,55%, no perÃodo de 40 dias; as leiras sob o modo negativo, de 21,78%, no perÃodo de 50 dias; e as leiras sob o modo hÃbrido de 31,21%, no perÃodo de 30 dias. Durante a fase de maturaÃÃo, para as leiras que sofreram reviramento, a reduÃÃo mÃdia de Carbono foi de 50,63%, no perÃodo de 50 dias, enquanto que as demais apresentaram uma reduÃÃo mÃdia de 39,54%, no perÃodo de 60 dias. O pH se mostrou Ãcido no material e no inÃcio do processo de compostagem, em todas as leiras. Os resultados obtidos mostraram que os valores mÃdios do Ãndice pH foram aumentando de acordo com a degradaÃÃo da matÃria orgÃnica. Na fase de maturaÃÃo, o pH permaneceu na faixa alcalina em todas as leiras. Durante fase ativa, o teor de nitrogÃnio cresceu, em mÃdia, 41,12% nas leiras sob o modo positivo, 54,21% nas leiras sob o modo negativo e 32,05% nas leiras sob o modo hÃbrido. Durante fase ativa, as leiras operacionalizadas sob o modo positivo apresentaram uma reduÃÃo da relaÃÃo C/N de 47,89%, em 40 dias; as leiras sob o modo negativo, de 44,35%, em 50 dias; e as leiras sob o modo hÃbrido, de 48,33%, em 30 dias. PÃde-se observar que a relaÃÃo C/N final na fase de maturaÃÃo das leiras que foram reviradas, apresentou valores mÃdios na ordem de 10 a 15 no perÃodo de 50 dias. As leiras operacionalizadas sob o modo positivo tambÃm registraram valores dentro desta faixa, porÃm no perÃodo de 60 dias, enquanto que as leiras operacionalizadas sob o modo negativo registraram valores mÃdios superiores ao recomendado pela legislaÃÃo, tambÃm no perÃodo de 60 dias. Observou-se que em todos os sistemas os Coliformes Totais e Fecais ou Termotolerantes foram diminuindo durante a fase de aeraÃÃo (fase de degradaÃÃo ativa). As leiras operacionalizadas sob o modo positivo registraram valores de Coliformes Totais da ordem de 9,1x108 a 5,0x103 UFC. g-Âe de Coliformes Fecais da ordem de 6,2x108 a 3,1x103 UFCg-1; as leiras operacionalizadas sob o modo negativo registraram valores de Coliformes Totais da ordem de 8,4x108 a 4,8x103 UFC.g-1 e de Coliformes Fecais da ordem de 6,1x108 a 3,5x103 UFC.g-1 ; e as leiras operacionalizadas sob o modo hibrido registraram valores de Coliformes Totais da ordem de 9,2x107 a 4,1x103 UFC.g  e de Coliformes Fecais,da ordem de 5,2x108a 3,2x103 UFC.g-1 A temperatura foi o parÃmetro utilizado para avaliar a eficiÃncia do processo de compostagem, durante a fase ativa. O tÃrmino da fase de maturaÃÃo foi verificado por meio da relaÃÃo C/N. A anÃlise dos resultados obtidos para os parÃmetros fÃsicos, quÃmicos, e microbiolÃgicos nos trÃs sistemas avaliados neste trabalho permite inferir sobre o desempenho satisfatÃrio dos sistemas operacionalizados sob os modos positivo e hibrido. Com relaÃÃo à aeraÃÃo na primeira fase do processo, pode-se afirmar que seu efeito contribuiu satisfatoriamente, tanto na eliminaÃÃo de patÃgenos como na diminuiÃÃo do tempo de compostagem, acelerando a metabolizaÃÃo da matÃria orgÃnica. De posse dos resultados das anÃlises dos experimentos e interpretaÃÃo dos dados, observou-se que o sistema hÃbrido proposto neste trabalho apresentou ser mais eficiente que os demais. / In this research, it was aimed to evaluate the process of composting using the organic matter available at the bank of seedlings of the city of Sobral - CE, (horse manure and straw of carnauba) in three aeration systems: with injection of air, sucking of the air and injection and sucking in air cycle (hybrid), in compliance with the parameters recommended by Brazilian legislation in force, during the phases of active degradation and maturation. The experiment was installed with three treatments, one (01) under the positive way; one (01) under the negative way and one (01) under the hybrid way, following the proportions of 30% of horse manure and 70% of straw , for all treatments. Each treatment was repeated three (3) times, making, thus, a total of 9 (nine) parcels. It was conducted the evaluation of these processes, and it was observed mainly the influence of aeration and moisture in the performance of these techniques of treatment, on static. During the active phase, the under positive way they developed average reduction of organic matter of 26.55%, the under the negative way of 21.78%, while the, under the hybrid way of 31.21%. During the phase of maturation, it was turned three of each system of aeration. The reduction of organic matter of them was 50,63%, in 50 days; The other ones showed average reduction of 39,54%, in 60 days. During the active phase, the operated under the positive way had, on average, reduction of carbon of 26.55%, in the period of 40 days, the under the negative mode of 21.78%, in the period of 50 days, and the under the hybrid way of 31.21%, within 30 days. During the stage of maturity, for the that suffered of returning, the average reduction of carbon was 50.63%, in the period of 50 days, while the other ones showed an average decrease of 39.54%, in the period of 60 days. On all the, the pH developed in the material and in the beginning of the process of composting was acid. The results showed that the average pH was increasing according to the degradation of organic matter. At the stage of maturity, the pH remained in the alkaline range on all the. During the active phase, the content of nitrogen grown by an average of 41.12% on the under the positive way, 54.21% on the under the negative mode and 32.05% on the under the hybrid way. During the maturation, the content of nitrogen on all, regardless of the used method of aeration, presented quite different results. During active phase, the operated under the positive way showed a reduction of the C/N nitrogen of 47.89% in 40 days, the piles under the negative mode of 44.35% in 50 days; and piles under the hybrid way of 48.33%, in 30 days. It was observed that the C/N in the final stage of maturation of the that were returned, presented average values in the order of 10 to 15 in the period of 50 days. The under the operational way also recorded positive values within this range, but in the period of 60 days, while the piles under the operational mode registered negative average above the recommended by the law, in the period of 60 days. It was observed that in all the systems the Total Coliform and the Fecal Coliform were decreasing during the aeration (active phase of degradation). The under the operational mode recorded positive values of Total Coliform in the order of 9,1x108 to 5,0 x103 CFU.g-1 and of Fecal Coliform of the order of 6,2 x108 to 3,1 x103 UFCg-1, and the operational under the negative way registered values of Total Coliform in the order of 8,4 x108 to 4,8 x103 CFU.g-1 and of Fecal Coliform in the order of 6,1 x108 to 3,5 x103 CFU.g-1, and the piles under the hybrid way recorded values of Total Coliform in the order of 4,1 to 9,2 x107 and x103 CFU.g  and of Fecal Coliform, in the order of 5,2 x108 to 3,2 x103 CFU.g-1. The temperature was the factor used to evaluate the efficiency of the composting process, during the active phase. The end of the stage of maturity was verified by the C/N. The analysis of the results for the physical, chemical and microbiological systems in the three evaluated systems in this research were possible because of the satisfactory performance of the systems operated under the positive and hybrid ways. Regarding the aeration in the first phase of the trial, one can say that its effect contributed satisfactorily for the elimination of pathogens, such as decreasing the time of composting, accelerating the metabolism of organic matter. By the results of the analyses of the experiments and also the interpretation of the data, it was observed that the hybrid system of this research was more efficient than the others ones.

La pérennité du compostage est cautionnée à une meilleure maîtrise de la qualité des composts ainsi que des émissions gazeuses. Ces deux critères dépendent en partie des conditions de compostage. Néanmoins, le contrôle des émissions gazeuses et des odeurs ne peut se circonscrire à une seule stratégie préventive. L'identification des composés responsables de l'odeur apparaît comme un enjeu permettant d'augmenter l'efficacité des solutions curatives. Cette thèse a eu pour double objectif d'évaluer l'influence des déterminants des procédés de compostage par aération forcée sur la qualité des composts, les émissions gazeuses et les odeurs en compostage et stockage ainsi que d'investiguer les corrélations entre composition chimique (CC) et concentration d'odeur (CO)des gaz émis. Le déchet et le structurant utilisés ont été des boues d'abattoir de porcs et des plaquettes de bois. L'influence des conditions opératoires a été évaluée en réacteur de compostage au regard des critères que sont la stabilisation, l'hygiènisation, le séchage et la conservation de l'azote. Un taux d'aération intermédiaire, un ratio structurant/déchet (S/D) >1 et une granulométrie >10mm semblent être les conditions répondant au mieux aux attentes d'un traitement par compostage. L'étude de l'influence des conditions sur les composés gazeux suspectés les plus contributrices des odeurs a conduit à une caractérisation exhaustive des émissions d'ammoniac, d'hydrogène sulfuré, des mercaptans par piégeage chimique et des COV par TD-GC-MS. L'identification des composés potentiellement contributeurs de l'odeur s'est basée sur le calcul d'unité d'odeur (UO) de chacun des composés i.e. le rapport de leur concentration chimique sur leur seuil olfactif, à leur pic d'émission. Les conditions opératoires générant le moins d'émissions sont un faible taux d'aération, un ratio S/D >1 et une granulométrie >10mm. Le potentiel des conditions opératoire à diminuer les émissions de composés odorants est toutefois limité. Les travaux venant d'être décrits ont été complétés d'une part par des mesures olfactométriques des émissions et leur corrélation à leur CC et d'autre part par la mise en œuvre de simulations de stockage en vue de comparer leurs émissions et odeurs à celles du compostage. Ces caractérisations ont montré que les pics d'odeurs en compostage sont 50 fois supérieurs à ceux du stockage. Deux types de corrélations entre la CC et la CO des gaz issus du compostage et du stockage ont été investiguées. Le premier type présume que la CO correspond à la somme des UO des composés du mélange. Le second suppose que la CO du mélange corresponde à l'UO la plus élevée (UOMAX) parmi l'ensemble des composés du mélange. Une analyse qualitative et quantitative des types de corrélations testés a indiqué qu'UOMAX est plus proche de la CO mesurée. Seuls trois composés, l'hydrogène sulfuré, le méthanethiol et la triméthylamine rendent compte des odeurs mesurées. / Compost sustainability requires a better control of its compost quality and its gaseous emissions. Both were influenced by composting conditions. Nevertheless, controlling gaseous emissions and their odour can’t be assumed by a single preventive approach. The identification of the compounds involved in odour is also a way to improve the efficiency of curatives solutions. This thesis has been the dual objectives to assess the influence of the principal process conditions for the forced aeration composting on compost quality, gaseous emissions and odours during composting and storage, as well as find out a correlation between the chemical composition (CC) and the odour concentration (OC) of the emissions. The waste and the bulking agent used were pig slaughterhouse sludge and wood chips. The influence of the composting process conditions was studied on stabilization, disinfection, drying and nitrogen conservation during composting in pilot reactors. An intermediate rate, a bulking agent/ waste (BA/W) ratio >1 and a particle size >10mm seemed to be the optimal conditions which satisfy composting treatment expectations. The study of the composting process influence on the gaseous compounds supposed as main potential odour contributors led to an gases exhaustive characterizations, including: ammonia, hydrogen sulphide and mercaptans were quantified by chemical traps while TD-GC-MS was used for VOC. Compounds were screened as main odour contributor based on the compute of their odour unit (OU) of each compounds i.e. dividing their chemical concentration by their odour threshold, at their events of peak emission. The composting process conditions which reduced the emissions were, a low aeration rate, a high BA/W ratio and a particle size > 10mm. Composting process conditions had a limited impact on reducing emissions of odorous compounds. Further works were performed for establish a more accurate odour emission evaluation. On a first hand, olfactometric measurements were carried out in order to be correlated with their CC. On a second hand, experiments were designed to simulate storage with a view to compare their emissions and their odours with that in composting. These characterizations showed that the peaks of the odour emissions were found 50 folds higher during composting than during storage. Two types of correlations were investigated between the CC and the OC of gas samples from composting and storage. The first one assumed that, the OC of gas sample was equal to the sum of the OU of every odorous compound. The second one consisted to consider the OC was equal to the highest OU (OUMAX) of the most odorant compound in the sample. Qualitative and quantitative analyses were tested for the both correlation types, indicating that OUMAX is the expression which can provide the most accurate prediction of OC. Only three main odorous compounds were identified: trimethylamine, hydrogen sulphide and methanethiol.

Fundação de Amparo a Pesquisa do Estado de Minas Gerais / Composting is a safety environmental alternative to reuse and treat organic wastes produced by human-beings. Although decomposition naturally happens, the handling of some factors, such as oxygen level, temperature, moisture content and pH, can alter the process speed, accelerating microbial activity. Aeration is a crucial practice during the composting process, since it can ensure adequate oxygen supply, temperature control and moisture content reduction in the windrows. Therefore, this work aimed to develop an automated process of compost pile aeration in order to accelerate and optimize the production of biofertilizers in an industrial plant. The trial was carried out at Valoriza Fertilizantes Company located in the city of Uberlândia - MG. Based on previous tests done in the company s standard ventilation system an automated system of forced aeration (SAFA) was projected. After installing this system, moisture content, oxygen level and temperature tests were performed aiming to verify the efficiency of the developed aeration system. / A compostagem é uma alternativa ambientalmente correta para o aproveitamento e tratamento dos resíduos orgânicos gerados pelo homem. Apesar de a decomposição ocorrer naturalmente, a manipulação de alguns fatores, como o nível de oxigênio, a temperatura, o teor de umidade e o pH, podem alterar a velocidade do processo, acelerando a atividade microbiana. A aeração é uma prática crucial durante o processo de compostagem, pois pode garantir suprimentos adequados de oxigênio, controlar a temperatura e reduzir o teor de umidade nas leiras. Objetivou-se neste trabalho desenvolver um processo automatizado de aeração de leiras de compostagem para acelerar e otimizar a produção de biofertilizantes em uma planta industrial. O experimento foi conduzido na Empresa Valoriza Agronegócios com sede na cidade de Uberlândia - MG. Baseado em testes realizados no sistema de ventilação padrão da empresa foi projetado um sistema de aeração forçada automatizado (SAFA). Após a instalação do sistema, testes de umidade, do teor de oxigênio e de temperatura foram realizados para verificar a eficiência do sistema de aeração desenvolvido. / Mestre em Engenharia Mecânica