Produção de hidrogênio e metano em reatores anaeróbicos a partir do efluente do processamento do coco

Abstract

Energy sources usually used are fossil fuels, which are recursosexauríveis and combustion gases responsible for environmental damage generates. For these reasons, it is necessary to identify alternative energy sources that produce less negative impacts. In this scenario, the hydrogen arises as an alternative source of energy, since it is renewable and there's only generation combustion of oxygen and water, and therefore considered a clean fuel. Similarly, the methane is important in decentralised energy generation and contributes to increase the viability of implementing waste treatment processes. The fermentation is a biological process sustainably to produce hydrogen and methane, because you can use as many different types of agro-industrial waste substrate rich in carbs, minimizing the problems caused by the improper disposal of these materials, which can be harmful to the environment. On the above, the objective of this work was to apply agro-industrial residue of coconut processing in anaerobic reactors for biological production of hydrogen and methane, studying the acidogenic phase coupling with metanogênica serial reactors (two-phase system). For development, were used two anaerobic Fluidised bed reactors (RALF) in series, the first being for the biological production of hydrogen from the agro-industrial residue and the second for reusing the effluent of acidogênico first RALF, aiming at the production of methane. The reactors were operated under progressive increase of organic loading rate (TCO), varying the hydraulic detention time (TDH) of operation. For adhesion of microorganisms, employed as materials supports the expanded clay in the reactor for production of hydrogen and the shells of sururu on methane production reactor. It was found that the generation of hydrogen and methane in two-phase system. Higher income and percentage were obtained on biogas in the TDH of 2:00, corresponding to the values of 2.45 mol H2/mol glucose and 33.82%. Already the largest hydrogen production occurred in the TDH of 1:00, it was 0.57 L/h/l. for the production, income and the percentage in methane biogas, highest values were observed in the TDH of 12:00 am such values corresponded, respectively, to 1.56 L/h/L, 0.09 L CH4/g cod and 38.60%. During the operation of the reactors, were observed in all stages, the presence of acetic acid, butyric acid, propionic acid, caproic acid and ethanol. Compared to other systems of anaerobic digestion, two-phase system used in this work showed satisfactory performance parameters.