Methane production by high temperature anaerobic digestion of food wastes

This study targeted methane production and decrease of organic materials concentration by high temperature anaerobic digestion of food waste. A anaerobic reactor with circulation was employed and the operation condition as follows: high temperature of $45{\pm}2,$ 0.6 $kg-VS/m^3/d,$ HRT of 70 days, pH of $6.8{\sim}7.2$. The CODcr removal rate of $75%{\sim}85%$ with effluent of $14,000{\sim}19,000$ mg/L in case of influent of $75,000{\sim}95,000$ mg/L showed. In influent TS(Total Solid) and VS(Volatile Solid) concentration of $2.94%{\sim}5.09%,$ and $2.98{\sim}5.01%,$ the effluent concentration was $0.65{\sim}1.1%$ and $0.6%{\sim}0.8%,$ respectively. 0.28 $m^3-CH_4$ / kg-VS was averagely obtained in the system.

반응조의 유입수 CODcr농도를 $75000{\sim}95000mg/L$로 운전하였을 경우 유출수 CODcr농도는 $14000{\sim}19000mg/L$로서, 제거율은 $75{\sim}85%$로 나타났다. 고온소화$(45{\pm}2^{\circ}C)$로 운전한 결과 유입수 pH는 $4.2{\sim}4.5,$ 유출수의 pH는 $6.8{\sim}7.2$를 유지하였다. TS(총고형물질)와 VS(휘발성고형물질)의 유입수를 단계적으로 각각 $2.94{\sim}5.09%$와 $2.98{\sim}5.01%$로 유지할 경우, 유출수는 단계적으로 각각 $0.65{\sim}1.1%$와 $0.6{\sim}0.8%$였다. 유출수의 TS, VS의 제거율은 각각 78, 85%이었다. $CH_4$발생량은 0.28 $m^3-CH_4/kg-VS$이었다.