热处理时间对餐厨垃圾高温干式厌氧发酵的影响

Effect of heating time on high-temperature dry anaerobic fermentation of restaurant garbage

餐厨垃圾中有机物大部分以大分子的形式存在,对其进行热处理,破坏大分子有机物的存在形式,将会影响其干式厌氧发酵的过程。实验对餐厨垃圾进行了热处理(100℃),处理后将其在含固率(TS)20%、接种率25%的条件下进行高温55℃厌氧发酵。实验结果表明,热处理后,餐厨垃圾的理化性质发生显著变化,累计产气量、TS和VS的去除率均增大。当热处理时间为15 min时,餐厨垃圾的SCOD值最高,为59.49 g/L,比未处理时提高了3.3倍。同样该条件下,累计产气量也最高,为2 782.8 m L,与未处理相比累积产气量提高58.30%,第二产气高峰比未处理提前3天。各发酵瓶发酵前后TS、VS去除率的变化趋势与累计产气量的变化基本一致,累计产气量越大,TS、VS的去除率越大。

The organics in the restaurant garbage mainly exist as macromolecules,which could be changed by thermal treatment to improve the performance parameter of the dry anaerobic fermentation process.In the experiments,the restaurant garbage was processed by heating at 100℃.Then,it was digested at 55℃ as its total solid content and the inoculation rate were 20% and 25%,respectively.The results showed that physical and chemical properties of restaurant garbage changed significantly.The accumulative amount of biogas production,removal rate of TS and VS of the restaurant garbage increased after thermal process.When the heating time was15 minutes,the value of SCOD reached maximum and up to 59.49 g/L which was 3.3 times more than that of the untreated group.Under this condition,the value of accumulative biogas production was the highest and up to2 782.8 m L,which increased by 58.30%.Its second gas production peak appeared 3 days earlier than that of the untreated group.The tendency of TS and VS removal rate was similar to that of the accumulative amount of biogas production.The more the accumulative amount of biogas production was,the higher the removal rate of TS and VS was obtained.