Digestion Performance and Microbial Metabolic Mechanism in Thermophilic and Mesophilic Anaerobic Digesters Exposed to Elevated Loadings of Organic Fraction of Municipal Solid Waste

Abstract

Mesophilic and thermophilic anaerobic digestion reactors (MR and TR) for the organic fraction of municipal solid waste (OFMSW) were tested to reveal the differential microbial responses to increasing organic loading rate (OLR). MR exhibited faster adaptation and better performance at an OLR range of 1.0-2.

Effect of Combined Inoculation on Biogas Production from Hardly Degradable Material

“…The combined inoculation can possibly support nutrient enrichment that is very important for the anaerobic digestion process. However, the ISR of 2 has been previously reported as an optimum for the biogas production [24][25][26][27][28][29]. Values are the average of three determinations; the values in parentheses denote the standard deviation.…”

“…A suitable inoculum contains a high number of active microbes that convert the organic matter to biogas. Therefore, the source of inoculum will affect the digestion performance, as it alters the degradation rate, biogas composition, digestion time, and reactor stability [23][24][25]. It is reported [26] that the inoculum is not only used to provide microbial species but also serves as a source of nutrients enhancing the microbial activity, and thus an elevated amount of biogas is produced.…”

Two Phase Anaerobic Digestion System of Municipal Solid Waste by Utilizing Microaeration and Granular Activated Carbon

“…In order to stabilize the process, on day 125 the organic load was reduced to 4.5 kg COD/m 3 d during 40 days, subsequently it was reduced to 3 kg COD/m 3 d for a period of 40 days without the reactor reaching stability. Gao et al [48], who used OFMSW as a substrate, evaluated the effect of the increased organic load, described that greater than 2.5 gVS/Ld (equivalent to COD 3 g/Ld) causes VFA accumulation and generates an imbalance between the acidogenesis and methanogenesis phases in microbial community. From day 1 to 80, the amount of VFAs was maintained at 200 mg/L (Figure 3c); the COD removal was greater than 50% and the methane in the biogas was 70%.…”

BioEnergy and BioChemicals Production from Biomass and Residual Resources

“…The twenty-one published papers cover a variety of biomass or waste residuals that have been converted into different types of energy, biofuels or biochemicals including heat [1,11,16], methane [2,4,[7][8][9]17,[19][20][21], electricity [2,11,16], short chain fatty acids [2,19], ethanol [3,12,19], syngas [5,19], nutrient pellets [6], hydroxymethylfurfura [15], and hydrogen [2,10,14,18,19]. The key information including biomass or residuals, products, and technology for the production and type of research are summarized in Table 1.…”

“…Gao et al [8] investigated the effect of the organic loading rate on the microbial responses in both mesophilic and thermophilic anaerobic digestion reactors treating municipal solid waste.…”