초록
<P><B>Abstract</B></P> <P>Two fermenters were operated by semi-continuous mode with suspended biomass and glycerol at concentrations of 10 and 50 g/L to evaluate the semi-continuous operational conditions to hydrogen and volatile fatty acids production. A high hydrogen production in the semi-continuous reactors at the experiment was observed, with a drop during the test, mainly in the reactor with higher substrate concentration. The yield median of the semi-continuous reactors was 0.25 and 0.01 mol H<SUB>2</SUB>/mol glycerol, and the volumetric productivity median was 350 and 130 mL H<SUB>2</SUB>/L.d in SCR1 and SCR2 (10 and 50 g/L), respectively. It was possible to associate the high hydrogen and volatile fatty acids production in the semi-continuous reactors with the bacterial genus <I>Enterobacter</I>, and the low hydrogen production to the bacterial genus <I>Clostridium</I>.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The semi-continuous operation to H<SUB>2</SUB> and VFA production from crude glycerol. </LI> <LI> Satisfactory volumetric productivity and low H<SUB>2</SUB> yield. </LI> <LI> Association of the bacterial genus <I>Enterobacter</I> with high H<SUB>2</SUB> and VFA production. </LI> <LI> The low H<SUB>2</SUB> and VFA production associated with the <I>Clostridium</I> genus. </LI> </UL> </P>