不同储存条件下餐厨垃圾的变化特征及其厌氧消化产气潜力

餐厨垃圾在储存、运输过程中容易腐败变质,对其资源化利用有一定影响。考察了不同条件下储存时餐厨垃圾pH和细菌总数的变化规律,研究了室温以及5℃条件下,不同储存时间的餐厨垃圾的厌氧发酵产气潜力。结果表明:随储存温度的降低,餐厨垃圾pH值的下降趋势有所减缓,在5℃条件下,8 h内可使餐厨垃圾的pH维持在6.0以上;15℃下餐厨垃圾储存8 h以内,细菌总数小于1.0×10~6cfu/g。室温(30℃)新鲜垃圾的累积产气量最高,达到1 422 mL。在5℃下储存4 h内的餐厨垃圾,其厌氧发酵累积产气量与新鲜餐厨垃圾的产气结果相当,而在5℃下储存8 h时,产气量与新鲜垃圾相比下降了3%,之后,随着储存时间的延长,累积产气量逐渐下降。

CHARACTERISTICS AND BIOGAS PRODUCTION POTENTIAL OF ANAEROBIC DIGESTION OF KITCHEN WASTES UNDER DIFFERENT STORAGE CONDITIONS

Kitchen waste is easy to undergo deterioration,which has affected its resource utilization.The variation of pH and total bacterial count of kitchen wastes were investigated.Furthermore,the biogas production potential of anaerobic digestion of kitchen wastes under room temperature and 5℃ was studied.The result showed that the pH of kitchen wastes decreased slowly at low storage temperature with the time prolonged.The pH value of kitchen wastes could be maintained above 6.0 within 8 h at 5 ℃.The total bacteria count of kitchen wastes was less than 1.0 × 106 cfu/g within 8 h at 15 ℃.The fresh kitchen waste gave the maximum cumulative biogas yields of 1 422 mL.The cumulative biogas yields of kitchen wastes kept at 5 ℃ for 4 h had little difference from that of the fresh kitchen wastes,and it decreased by 3％ at 5 ℃ for 8 h.The cumulative biogas yields decreased with the time prolonged.