Produção de hidrogênio através da digestão anaeróbia de glicerol e vinhoto utilizando culturas mistas

Abstract

The fuel use increase in a global scale have caused rising energy demand, whether it's renewable or not. Since our energy matrix is still based on fossil fuels, it also means an increase in the environmental impact caused by burning sources derived from oil and coal. In this context, hydrogen is highlighted, as a gas that could play a significant role in the reduction of greenhouse gas (GHG) emissions and clean energy production, since hydrogen synthesis can be performed from organic waste using the anaerobic digestion process. At the national level, two residues stand out: glycerol and sugarcane vinasse. The first is the main by-product of the biodiesel industry, the second is the main residue of the sugar and ethanol industry. Thus, this research focused on establishing the best influence parameters in the hydrogen production process using vinasse and glycerol in batch mode operation reactors. It was concluded that the production of hydrogen only using vinasse had better results using pH 6.0 and pH 6.5, and the first study obtained higher accumulated total production (7,585 mL H2) and the second obtained a higher specific production rate (0.88 mmol H2.gSSV-1.h-1). The studies with mixture of the substrates shown that H2 production can be even more efficient in comparison with crude vinasse, and the best mixing ratio was with 80% of COD due to glycerol and 20% to vinhoto, in which there was total accumulated production 10.070 mL H2 and 0.85 mmol H2.gSSV-1.h-1.