Produção de hidrogênio a partir de cascas de banana em reator anaeróbio em batelada

Abstract

The global energy matrix is largely geared towards the use of fossil fuels, and this has major environmental impacts. Alternative sources of energy, including biohydrogen, appear as a substitute for these non-renewable fuels. For hydrogen production, we have anaerobic biodigestion, which stands out for the degradation of organic matter without the need for light and for being able to be conducted at low temperatures. Thus, this study aims to evaluate the efficiency of an anaerobic reactor in relation to the production of hydrogen from banana peel as a substrate. The tests were carried out in batch with controlled temperature (35 ± 1 ºC) and with agitation at 120 rpm, using as inoculum the sludge from an effluent treatment plant. The amounts of inoculum (0.139 g and 0.209 g of volatile solids (SV) per batch) and substrate (0.695 g and 2.78 g SV per batch) were varied, as were the initial pH values of 5.5 and 6. In addition, the effect of substrate pretreatment for all reaction conditions was evaluated. The best results for carbohydrate consumption, removal of chemical oxygen demand and hydrogen production were obtained in reactors with alkaline treatment of the substrate. Best result for the specific rate of hydrogen production was the R3 (with 209 g of SV per batch of inoculum, initial pH 6 and 0.695 g of SV per substrate batch), reaching the value of 309.82 mL.g-1SV when subjected to pretreatment of the substrate.