کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4996684 | 1459897 | 2018 | 8 صفحه PDF | دانلود رایگان |
- Successful acclimation of methanogenic culture to extreme ammonia levels in CSTR.
- Efficient utilization of a 3rd generation biomass as biomethanation substrate.
- The most abundant bacterium (Shinella spp.) was not affected by the ammonia levels.
- C. ultunense increased significantly its abundance during the acclimation process.
- Methanosarcina spp. was the most abundant methanogen at the highest ammonia levels.
Acclimatized anaerobic communities to high ammonia levels can offer a solution to the ammonia toxicity problem in biogas reactors. In the current study, a stepwise acclimation strategy up to 10 g NH4+-N Lâ1, was performed in mesophilic (37 ± 1 °C) continuously stirred tank reactors. The reactors were co-digesting (20/80 based on volatile solid) cattle slurry and microalgae, a protein-rich, 3rd generation biomass. Throughout the acclimation period, methane production was stable with more than 95% of the uninhibited yield. Next generation 16S rRNA gene sequencing revealed a dramatic microbiome change throughout the ammonia acclimation process. Clostridium ultunense, a syntrophic acetate oxidizing bacteria, increased significantly alongside with hydrogenotrophic methanogen Methanoculleus spp., indicating strong hydrogenotrophic methanogenic activity at extreme ammonia levels (>7 g NH4+-N Lâ1). Overall, this study demonstrated for the first time that acclimation of methanogenic communities to extreme ammonia levels in continuous AD process is possible, by developing a specialised acclimation AD microbiome.
142
Journal: Bioresource Technology - Volume 247, January 2018, Pages 616-623