Food Waste Composting by Soil Microbial Inoculators

토양미생물제제에 의한 음식물폐기물의 퇴비화 검토

This study was performed to evaluate efficiency of soil microbial inoculator for active composting of food waste. In addition the number of microorganisms in roil microbial inoculator and the effect of seeding in the process of composting were investigated. food waste samples collected from a refectory were analyzed for physical-chemical properties. The samples were adjusted to moisture content of 65% by saw dust and seeded with soil microbial inoculator of 10% by the weight in case of reactor B. The number of microorganisms, aerobic bacteria, actinomyces, yeast, and fungi in soil microbial inoculator were over $2.98{\times}10^9/g$, $3.93{\times}10^7/g$, $1.21{\times} 10^5/g$, and $5.79{\times}10^7/g$, respectively. During the process of composting, the highest temperatures were $63.4^{\circ}C$ at reactor A(unseeded control)after 10 days and $66.8^{\circ}C$ at reactor B(seeded compost) after 4 days. The pH values of reactor A and B rapidly increased after 3 days and after first few days during composting period, respectively. The highest $CO_2$ concentrations were 6.1%(after 10 days) and 10.8%(afer 4 days) in reactor A and B, respectively. The degradation rates of organic matter(rd) between reactor A and B increased by 17.1% and 64.5%, respectively Consequently, the effects of Inoculation on comporting parameter such as temperature increasing, pH change, chemical properties, and the degradation rates of organic matter(rd) were higher in seeded compost than in unseeded control.

음식물 퇴비화를 위한 토양미생물제재의 퇴비화 효율을 평가하며, 토양미생물제재의 미생물수와 퇴비화과정에서 식종의 효과를 조사하였다. 분석대상 음식물은 본 연구원 구내식당에서 수거한 후 물리화학적특성을 분석하였다. 대상시료는 Bulking Agent로서 톱밥을 사용하여 함수율을 65%로 조정 후 반응기 B에 10%의 토양미생물제를 식종하였다. 토양미생물제제의 미생물은 호기성세균수가 $2.98{\times}10^9/g$이상, 방선균이 $3.93{\times}10^7/g$이상, 효모가 $1.21{\times} 10^5/g$, 균류가 $5.79{\times}10^7/g$ 이상이었다. 퇴비화 기간동안 최고온도는 Reactor A가 반응 10일후에 개시후 바로 급격한 변화를 보였으며, 반응이 종료된 후 두 Reactor 공히 pH8.9를 나타내었다. Reactor B의 경우 최대온도인 4일후에 $CO_2$농도도 역시 최대인 10.8%를 나타냈으며, Reactor A는 최대온도인 10일후에 6.1%를 나타내었다. 한편 Reactor A는 $r_{d}$(유기물질의 분해율)치가 0.35에서 0.41로 17.1%상승하였으며, Reactor B의 경우 0.31에서 0.51로 64.5%상승하였다.