혐기성 소화에서 음식물류폐기물과 폐활성슬러지의 기질과 미생물 비 그리고 혼합 비에 따른 메탄생성 특성

Effect of Substrate to Inoculum Ratios and Mixing Ration of Food Waste and Waste Activated Sludge on Methane Production in Anaerobic Digestion

This study investigated the effect of the substrate-to-inoculum (S/I) ratio and the mixing ratio of food waste (FW) and waste activated sludge (WAS) on methane production characteristics during anaerobic digestion (AD). Anaerobic digestion has emerged as an effective alternative for reducing the volume of organic waste, stabilizing it, and producing renewable bio-methane. Biochemical methane potential (BMP) tests were conducted at S/I ratios of 0.3, 0.5, 1, 2, and 5. The highest methane yield was observed at an S/I ratio of 0.3. However, considering economic feasibility, process efficiency, and the difficulty of maintaining microbial concentration, and optimal S/I ratio of 0.5 was selected. Applying the optimal S/I ratio, co-digestion BMP tests were performed with FW-to-WAS mixing ration of 100%, 75%, 50%, 25% and 0%. The results showed that the highest methane yields were obtained form 100% FW and from the 75% FW-25% WAS mixture. The comprison between theoretical and experimental methane yields confirmed that the 75% FW-25% WAS mixture achieved the highest biodegradability of approximately 87.7%, indicating that this ratio represents the optimal condition for co-digestion.