초록
<P><B>Abstract</B></P> <P>Dry fermentation of food waste was optimized to achieve the maximum solid loading rate for carboxylate production without clogging events in a dry fermenter run at neutral pH. High inoculum-to-substrate ratio improved food waste solubilization and carboxylate yield, but the ratio 15% completely clogged the dry fermenter. Higher leachate circulate rate tended to enhance food waste fermentation, but partial clogging was observed at 13.2 L/h of leachate circulation rate. The dry fermenter achieved carboxylate yield of 428.5 g/kg food waste and volatile solid reduction of 79% at the solid loading rate 4.82 kg volatile solids/m<SUP>3</SUP>-d. This study first tracks chemical oxygen demand (COD) in food waste dry fermentation, showing maximum soluble COD <60% of food waste COD with residual food waste 13.6–16.3%. The operating cost was as low as $1.7/ton FW, implying that food waste treatment will be cost-neutral if recovered carboxylate can create economic benefit over the operating cost.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The maximum solid loading rate of 4.62 kg VS/m<SUP>3</SUP>-d was achieved in the LBR. </LI> <LI> Carboxylate yield became highest at 544 g SCOD/kg VS<SUB>added</SUB>. </LI> <LI> LBR operation at the inoculum-to-substrate ratio 15% caused severe clogging. </LI> <LI> The maximum SCOD is <60% of food waste COD in the LBR. </LI> <LI> The operating cost was as small as $1.7/ton food waste. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>