초록
<P><B>Abstract</B></P> <P>This study explored the volatile fatty acid (VFA) production potential of seven waste streams from urban and agroindustrial sources. For that purpose, batch assays were performed under acidic (pH 5.5) and alkaline (pH 10) conditions at both mesophilic (35°C) and thermophilic (55°C) temperature. Overall, the VFA yield was influenced by temperature, and it was positively affected by pH, ranging between 220 and 677mgCODg<SUP>−1</SUP> COD<SUB>fed</SUB> for liquid waste streams and between 127 and 611mgCODg<SUP>−1</SUP> COD<SUB>fed</SUB> for solid waste streams and urban sludge. The highest VFA concentration and highest VFA/sCOD ratio was obtained during the organic fraction of municipal solid waste (OFMSW) fermentation, with 8,320mgCODL<SUP>−1</SUP> and 94% at alkaline pH and mesophilic temperature. The results of this study suggest that selective VFA production, i.e. via propionic, butyric and acetic acid production, might be feasible for scaling-up purposes with specific waste streams by adjusting the process parameters.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Seven organic waste streams were treated in mixed culture fermentation processes. </LI> <LI> Slaughterhouse wastewater produced the highest VFA yield, followed by the OFMSW. </LI> <LI> Acetic acid and VFA yield should be enhanced under alkaline pH (i.e. 10). </LI> <LI> Carbohydrate rich waste streams led to propionic and butyric acid production. </LI> <LI> Valeric and iso-valeric acids can be produced from proteinaceous rich waste streams. </LI> </UL> </P>