Recovery of failed solid-state anaerobic digesters

作者：Yang Liangcheng; Ge Xumeng; Li Yebo^*

来源：Bioresource Technology, 2016, 214: 866-870.

DOI：10.1016/j.biortech.2016.04.126

• Digester failure
• Recovery
• Mass transfer
• Solid-state anaerobic digestion

This study examined the performance of three methods for recovering failed solid-state anaerobic digesters. The 9-L digesters, which were fed with corn stover, failed at a feedstock/inoculum (F/I) ratio of 10 with negligible methane yields. To recover the systems, inoculum was added to bring the F/I ratio to 4. Inoculum was either added to the top of a failed digester, injected into it, or well-mixed with the existing feedstock. Digesters using top-addition and injection methods quickly resumed and achieved peak yields in 10 days, while digesters using well-mixed method recovered slowly but showed 50% higher peak yields. Overall, these methods recovered 30-40% methane from failed digesters. The well-mixed method showed the highest methane yield, followed by the injection and top-addition methods. Recovered digesters outperformed digesters had a constant F/I ratio of 4. Slow mass transfer and slow growth of microbes were believed to be the major limiting factors for recovery.

• 出版日期2016-8