探討以皮革浸灰削肉廢棄物和稻稈調整碳氮比對厭氧共消化的影響

Abstract

本研究旨在探討不同比例的皮革浸灰削肉廢棄物及稻稈調整碳氮比對於厭氧共消化的產甲烷表現、消化液狀況變化及固體消化率的影響。試驗調整碳氮比10、15、20及25，每組三重複，以批次式中溫、液態及固定起始pH等條件進行厭氧共消化，為期48天，測定產氣表現、消化液成分及固體消化率。研究結果顯示，碳氮比為10的處理組於總甲烷產量、每日平均甲烷產量、固體消化率及甲烷生產效率等指標中表現最佳，然其批次的厭氧消化時間約42天，為處理組中耗時最長者，而消化液總氨氮濃度高；當碳氮比提升時，總甲烷產量、固體消化率及甲烷生產效率則隨之下降，同時批次的厭氧消化時間縮短，消化液總氨氮濃度下降。此結果顯示，添加稻稈使碳氮比高於10，無法提升甲烷生產與皮革浸灰削肉廢棄物之處理效率，未來可尋求比稻稈更合適的高碳原料組合、降低含水量及調整接種比例等方向進行研究。

This study aimed to investigate the effect of different carbon to nitrogen ratios (C/N) on methane yield, changes of liquid phase, and solid digestibility in anaerobic co-digestion of leather limed fleshing mixed with rice straws. Four treatments with C/N of 10, 15, 20 and 25 were operated in liquid-state mesophilic batch experiment in triplicates at the same initial pH value. After 48 days of digestion, results showed that C/N of 10 had the highest total methane yield, daily average methane yield, solid digestion, and methane productivity, whereas its digestion time (42 days) was the longest among treatments and had the highest concentration of total ammonia nitrogen. On the contrary, when increasing C/N, decreased total methane yield, solid digestion, and methane productivity were observed. However, it followed by shorter digestion time and lower production of total ammonia nitrogen. In conclusion, adding rice straws to increase C/N above 10 could not benefit in either methane yield or disposing leather limed fleshing. Future work should focus on searching for other high-degradable carbon source, increasing solid content, and optimizing inoculum to substrate ratio in hope for improving methane yield.