多段型UASBリアクターによる焼酎蒸留粕廃液の超高速メタン発酵処理

スタートアップ期間及び再スタートアップ期間のプロセス挙動

抄録

Process performance of thermophilic multi-staged UASB reactor was investigated by feeding a Shochu stillage wastewater. The reactor was seeded with mesophilic sewage digested sludge, and operated at 55° over 900 days. Granulation successfully accomplished within the first three months. As a result, the reactor steadily allowed a super high rate COD loading rate of 100 kg COD ·m^-3·d^-1, which is equivalent to the influent strength of 10, 000 mg COD·1^-1at a HRT of only 2.4 h, keeping COD removal of above 90%. Microbial consortia analys s of the retained sludge by 16S rRNA approach revealed that drastic microbial composition shift from mesophilic methanogens to thermophilic methanogens during 300 days operation under thermophilic conditions: Predominance of Methanosaeta concilii and Methanospirillum hungatei in the initial stage (mesophilically grown sludge) was thoroughly replaced by Methanosaeta thermophila and Methanothermobacter thermautotrophicus.