Performance and microbial community dynamics in a two-phase anaerobic co-digestion system using cassava dregs and pig manure

• Published in: Bioresource technology 2014-03, Vol.155, p.342-351
• Main Authors: Ren, Jiwei, Yuan, Xufeng, Li, Jie, Ma, Xuguang, Zhao, Ye, Zhu, Wanbing, Wang, Xiaofen, Cui, Zongjun
• Format: Article
• Language: English
• Subjects: Acidification; Ammonia - metabolism; Animals; Archaea; Bacteria; Bacteria, Anaerobic - metabolism; Bacteroidetes - genetics; Bacteroidetes - metabolism; Base Sequence; Biological and medical sciences; Biological Oxygen Demand Analysis; Biological treatment of sewage sludges and wastes; Bioreactors; Biotechnology; Cassava; Cassava dregs; Cluster Analysis; Co-digestion; Computational Biology; Denaturing Gradient Gel Electrophoresis; DNA Primers - genetics; Dynamical systems; Dynamics; Environment and pollution; Fatty Acids, Volatile - metabolism; Firmicutes; Fundamental and applied biological sciences. Psychology; Gram-Positive Bacteria - genetics; Gram-Positive Bacteria - metabolism; Hydrogen-Ion Concentration; Industrial applications and implications. Economical aspects; Manihot - chemistry; Manihot - metabolism; Manihot esculenta; Manure; Manure - analysis; Methane; Methane - biosynthesis; Methanobacteriales - genetics; Methanobacteriales - metabolism; Methanogens; Methanomicrobiales; Methanomicrobiales - genetics; Methanomicrobiales - metabolism; Microorganisms; Molecular Sequence Data; Phylogeny; Pig manure; Polymerase Chain Reaction; RNA, Ribosomal, 16S - genetics; Sequence Analysis, DNA; Swine; Two-phase
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2013.12.120

•The two-phase anaerobic co-digestion of CD with PM was evaluated using 4 SBRs and a CSTR.•Co-acidification of PM and CD promoted the production and accumulation of VFAs, SCOD and NH4–N.•Methanogenic fermentation of the acidification products was efficient and steady.•Co-digestion of PM and CD supported higher quantity and diversity of methanogens. The two-phase anaerobic co-digestion of cassava dregs (CD) with pig manure (PM) was evaluated using four sequencing batch reactors (SBRs) and a continuously stirred tank reactor (CSTR). The effect of seven different PM to CD volatile solid ratios (10:0, 8:2, 6:4, 5:5, 4:6, 2:8 and 0:10) on the acidification phase was investigated. Results indicated the concentrations of soluble chemical oxygen demand, NH4–N and volatile fatty acids increased substantially at seven ratios. Co-acidification of PM and CD performed well. Methanogenic fermentation of the acidification products at seven ratios was steady in CSTR. The highest methane yield and VS removal of 0.352m3/kg VSadded and 68.5% were achieved at PM:CD (4:6). The microbial population in CSTR was analyzed using molecular methods. Findings revealed that bacteria such as Firmicutes and Bacteroidetes, archaea such as Methanobacteriales and Methanomicrobiales were advantageous populations. Co-digestion of PM and CD supported higher quantity and diversity of methanogens.