Effects of liquid fraction of digestate recirculation on system performance and microbial community structure during serial anaerobic digestion of completely stirred tank reactors for corn stover

Effect of digestate application on microbial respiration and bacterial communities' diversity during bioremediation of weathered petroleum hydrocarbons contaminated soils

“…In contrast, in digestate and amended soils the most frequent were Microgenomates, known previously as candidate phylum OP11 (33.5 % in digestate). This taxa was previously found in anaerobic bioreactor with artificial sewage and constituted around 30 % of microbial population (Gao et al, 2010) and in corn stove digestate (around 1 %) (Li et al, 2018). Other phyla identified in digestate belong to Proteobacteria (17.5 %), Aminicenantes (14 %) and Actinobacteria (10.8 %).…”

Microbiome Diversity and Community-Level Change Points within Manure-based small Biogas Plants

“…Both modifications apparently led to process stabilization indicated by a decreasing VFA concentration over a period of two months ( Figure 1 b and Table S1 ). This might be related to the reduction in the overall microbial metabolic activity as well as the increased degradation efficiency, or in this case, most preferentially the degradation of organic acids by “starved” microorganisms [ 91 , 92 ] which were in this case already adapted to the mesophilic temperature (32.9 °C ± 4.1 °C within the digestate storage tank). Due to the supposed process stabilization, the plant operator increased the process temperature again ( Figure 1 a and Table S1 ), which directly resulted in a serious process disturbance indicated by a massive drop in the amount of produced biogas ( Figure 1 d and Table S1 ).…”

Achieve clean and efficient biomethane production by matching between digestate recirculation and straw-to-manure feeding ratios

“…As a result, the stability of digesters was improved by recirculation through reutilization of the buffer substances and nitrogen nutrients, so the longer period of high process performance was achieved in Ar than A. Consistent conclusions were draw in Li et al (2018) and Peng et al (2016),…”

“…However, it is worthwhile to further study the optimization of liquid digestate recirculation under these feedstock conditions and other types of raw material in the future, which is conducive to reducing the discharge of liquid digestate from the source and making full use of water, heat, and substances in liquid digestate. Li et al (2018) and Peng et al (2016) also studied the effect of liquid digestate recirculation on digesting CS, pretreatment methods (NaOH), buffering agents (NaHCO 3 ), and longer HRT (40-45 d) were used, which could make straw easier to degrade, provide better conditions, and more time for microorganisms to degrade. As a result, no process failure occurred, and long-term, stable, and efficient fermentation was…”