Advanced Search
Study of microbial community and biogas production in anaerobic digestion of pig manure with digested slurry recirculation
Received:September 12, 2017  
View Full Text  View/Add Comment  Download reader
KeyWord:anaerobic digestion;recirculation;pig manure;microbial community;microbial diversity
Author NameAffiliationE-mail
KONG De-wang College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, China
Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China 
 
ZHANG Ke-qiang Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China  
FANG Fang Tianjin Huankeyuan Environmental Science and Technology Limited, Tianjin 300191, China  
GAO Wen-xuan Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China  
LIANG Jun-feng Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China  
LIANG Yu Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China  
DU Lian-zhu Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, China dulianzhu99@163.com 
Hits: 2256
Download times: 2880
Abstract:
      In order to investigate the characteristics of microbial community and its relationship with biogas production in an anaerobic digestion reactor with digested slurry recirculation, a continuous stirred-tank reactor(CSTR) was operated and the microbial community was analyzed by Miseq high-throughput sequencing. Results indicated that the richness and diversity of bacteria were higher than that of archaea, and they increased in bacteria, but no obvious difference could be observed in archaea, even by prolonging the experiment time. The bacterial structures consisted of eight categories, such as Firmicutes, Bacteroidetes, and Proteobacteria at phylum level. Firmicute was the most prevalent in the reactor; its relative abundance increased from 62.79% to 81.46%. The main class and genus were Clostridia and Clostridium, whose relative abundance changed from 58.62% and 35.44% to 68.19% and 39.10%, respectively. For archaeal communities, Euryarchaeota showed an absolute predominance, accounting for 94.76%, 99.89%, and 99.59% at inoculation, 68 d, and 219 d, respectively. This phylum included seven genera, of which the relative abundance of Methanosarcina increased from 23.99% to 72.28%, but that of Methanobrevibacter and Methanosphaera decreased from 16.34% and 21.71% to 3.70% and 12.93%, respectively. Specific methane yield increased from 409 mL·g-1 to 477 mL·g-1. The concentration of ammonia and VFA increased gradually, and the biogas yield was maintained at a relatively high level without any inhibition. The results indicated that Clostridium and Methanosarcina were the dominant genera in the reactor, and the relative abundance increased with an increase in recirculation time. The specific methane yield showed positive correlations with the relative abundance of Clostridium and Methanosarcina, whereas it showed negative correlations with Methanobrevibacter and Methanosphaera.