초록
<P><B>Abstract</B></P> <P>This study investigates the effects of anaerobic co-digestion of a fishery by-products broth (FFB) mixed with sewage sludge on biogas production and sludge reduction. A 5:5 mixing ratio of sewage sludge and FFB generated the highest removal efficiency of volatile solids (VS) (51.3%), total solids (TS) (48.7%) and chemical oxygen demand (COD) (51.3%). In addition, the highest biogas production (0.585 L/g·VS<SUB>in</SUB>·d) was also achieved with a mixing ratio of 5:5, followed 0.305 L/g·VS<SUB>in</SUB>·d for 7:3. The methane content in produced biogas was associated more than 70% with ratios of 7:3 and 5:5. Moreover, the 5:5 ratio produced the greatest amount of the energy recovered at 4.1 kWh, followed by the 7:3 mixing ratio at 3.4 kWh. Therefore, the mixing ratio from 7:3 to 5:5 for anaerobic co-digestion of sewage sludge and FFB may be suitable for biogas production and organic matter removal. However, a 5:5 mixing ratio is recommended for anaerobic digestion of sewage sludge and FFB because it has the highest digestion efficiency, can treat larger quantities of fish by-products, and can recover the most energy. Biogas produced by mixing FFB with sewage sludge opens up the possibility of biogas production using organic waste because of the higher methane content.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A fish by-product fermentation broth (FFB) for sludge reduction and biogas production. </LI> <LI> Mixing of FFB and sewage sludge at various ratios in anaerobic co-digestion. </LI> <LI> The 5:5 mixing ratio was a highest sludge reduction and biogas production. </LI> <LI> The highest biogas production was 0.585 L/g·VS<SUB>in</SUB>·d with a methane content of 71.8%. </LI> <LI> FFB is suitable for biogas production and sludge reduction in anaerobic co-digestion. </LI> </UL> </P>