Responses of anaerobic microorganisms to different culture conditions and corresponding effects on biogas production and solid digestate quality

Abstract

Microbial communities of anaerobic digestion have been intensively investigated in the past decades. Majority of these studies focused on correlating microbial diversity with biogas production. The relationship between microbial communities and compositional changes of the solid digestate (AD fiber) has not been comprehensively studied to date. Therefore, the objective of this study was to understand the responses of microbial communities to different operational conditions of anaerobic co-digestion and their influences on biogas production and solid digestate quality. Two temperatures and three manureto-food waste ratios were investigated by a completely randomized design. Molecular analyses demonstrate that both temperature and manure-to-food waste ratio greatly influenced the bacterial communities, while archaeal communities were mainly influenced by temperature. The digestion performance showed that biogas productivity increased with the increase of supplemental food wastes, and there were no significant differences on carbohydrate contents among different digestions. The statistical analyses conclude that microbes changed their community configuration under different conditions to enhance digestion performance for biogas and homogenized solid digestate production.

Anaerobic co-digestion of pre-treated press mud and Molasses-based distillery wastewater enhanced biogas production

“…Generally, it decreases before to after digestion (AD) due to presence of high proportion of nondegradable materials [34]. For sugar waste products, optimum % (BOD/COD)I varies from 38.46% to 55.55%, which Sample 3 and Sample 5 followed [35].…”

Small-Scale Solar–Bio-Hybrid Power Generation Using Brayton and Rankine Cycles

“…Thermodynamic models were established to analyze solar-bio-hybrid systems with gas and steam turbines, respectively ( Figure 1). Biogas production for the studied systems was based on a biogas plant using thermophilic AD on the mixture feed of dairy manure and food wastes (90:10 ratio, 5% total solids) [15]. The AD with a culture temperature of 45 • C and a hydraulic retention time (HRT) of 20 days produced 0.64 m 3 biogas per m 3 digestion solution per day with 0.38 m 3 methane (the lower heating value (LHV) of biogas is 23 MJ/m 3 [16]) and 0.26 m 3 carbon dioxide.…”

Effects of Mediterranean agricultural residues on microbial community and anaerobic digestion performance

“…A Power-Soil DNA isolation kit (MO BIO Laboratories, Carlsbad, CA, USA) 15 was utilized to extract community genomic DNA from samples taken every 10 days, and a NanoDrop™ Lite spectrophotometer (Thermo Fisher Scientific Inc., Waltham, MA, USA) measured the DNA extraction. A polymerase chain reaction (PCR) was performed on the nucleotide extract using a universal cycle.…”

“…14 Besides feedstock availability, anaerobic microbes require balanced nutrientsfor example, a carbon : nitrogen ratio between 15 and 30. 15 Co-digestion of multiple feedstocks must satisfy such nutrient requirements to enhance the growth of anaerobic microbes and improve AD performance. Another study investigated the effects of different mixing ratios of multiple feedstocks on AD and found three preferred mixing ratios for good biogas production.…”