초록
<P><B>Abstract</B></P> <P>This work targeted the energy recovery from food waste (FW), aiming at the implementation of a potentially participative process of FW conditioning before the non-sterile biological conversion to hydrogen (H<SUB>2</SUB>). Food waste conversion was initially performed under sterile conditions, achieving a maximum H<SUB>2</SUB> productivity of 249.5 ± 24.6 mL H<SUB>2</SUB> (L h)<SUP>−1</SUP> and a total H<SUB>2</SUB> production to 4.1 ± 0.2 L L<SUP>−1</SUP>. The non-sterile operation was implemented as a way of process simplification, but the total H<SUB>2</SUB> production decreased by 59% due to the FW native microorganisms. To counteract this effect, FW was submitted to acid, microwave (MW), and combined acid and MW pretreatment. The application of 4 min MW, 550 W, efficiently controlled the FW microbial counts. The <I>Clostridium butyricum</I> bioaugmented conversion of MW-pretreated FW accelerated the H<SUB>2</SUB> production to 406.2 ± 8.1 mL (L h)<SUP>−1</SUP> and peaked the total H<SUB>2</SUB> production and conversion yield to 4.6 ± 0.5 L L<SUP>−1</SUP> and 234.6 ± 55.6 mL (g sugar)<SUP>−1</SUP>, respectively. These results exceeded in 63, 12 and 4%, respectively, the H<SUB>2</SUB> productivity, total production and sugar conversion yield obtained under sterile conditions, and are encouraging for the future implementation of increasingly responsible waste valorisation practices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bioaugmentation with <I>C. butyricum</I> enhances the non-sterile H<SUB>2</SUB> production. </LI> <LI> Microwave pretreatment (MW) drastically reduces food waste (FW) microbial counts. </LI> <LI> Bioaugmentation + MW of FW improves H<SUB>2</SUB> productivity up to 406.2 ± 8.1 mL (L h)<SUP>−1</SUP>. </LI> <LI> Maximum potential energy recovery is estimated to be 746.3 ± 77.0 kJ kg<SUB>VS</SUB> <SUP>−1</SUP>. </LI> <LI> 58 g acetate kg<SUB>VS</SUB> <SUP>−1</SUP> and 113 g butyrate kg<SUB>VS</SUB> <SUP>−1</SUP> are recovered as byproducts. </LI> </UL> </P>