Produção de bio-hidrogênio a partir de frutas e vegetais residuais em reatores anaeróbios em batelada

Abstract

The amount of food losses has become an environmental, economic and social problem. Sustainable consumption and reuse can be alternatives to solve these problems. Anaerobic fermentation emerges as a low-cost alternative to reuse the residue, obtaining value-added products. This study investigated the effect of acid pretreatment (1,6-6,4% v/v), initial pH (4,00- 7,00) and inoculum size (25-75% v/v) on fermentative biohydrogen production by acclimatized mixed cultures (50% v/v of substrate in 50% v/v heat-treated anaerobic sludge) was investigated in batch tests, using a full factorial design. An anaerobic fermentation was conducted in serum bottle with 42 mL working volume incubated at 35±1°C and 120 rpm. Modified Gompertz model could describe the progress of cumulative hydrogen production in the batch tests of this study successfully. The experiment showed that initial pH and inoculum size significantly influenced biohydrogen production individually and interactively. The maximum hydrogen yield of 646.7 mL/g of carbohydrate consumed during the fermentation was estimated at the acid pretreatment of 6.4% v/v. While the maximum hydrogen production rate of 2.3 mL/h was estimated at the acid pretreatment of 1.6% v/v. In both cases, the initial pH was 4.00 and the inoculum size was 75% v/v. In general, the results showed the potential for hydrogen production under the applied conditions.