Bioaugmenting anaerobic digestion of biosolids with selected strains of Bacillus, Pseudomonas, and Actinomycetes species for increased methanogenesis and odor control

Abstract

The objective of this study was to evaluate the effects of bioaugmenting anaerobic biosolids digestion with a commercial product containing selected strains of bacteria from genera Bacillus, Pseudomonas, and Actinomycetes, along with ancillary organic compounds containing various micronutrients. Specifically, the effects of the bioaugment in terms of volatile solids destruction and generation and fate of odor-causing compounds during anaerobic digestion and during storage of the digested biosolids were studied. Two bench-scale anaerobic digesters receiving primary and secondary clarifier biosolids from various full-scale biological wastewater treatment plants were operated. One of the digesters received the bioaugment developed by Organica Biotech, while the other was operated as control. The bioaugmented digester generated 29% more net CH(4) during the 8 weeks of operation. In addition, the average residual propionic acid concentration in the bioaugmented digester was 54% of that in the control. The monitoring of two organic sulfide compounds, methyl mercaptan (CH(3)SH) and dimethyl sulfide (CH(3)SCH(3)), clearly demonstrated the beneficial effects of the bioaugmentation in terms of odor control. The biosolids digested in the bioaugmented digester generated a negligible amount of CH(3)SH during 10 days of post-digestion storage, while CH(3)SH concentration in the control reached nearly 300 ppm(v) during the same period. Similarly, peak CH(3)SCH(3) generated by stored biosolids from the bioaugmented digester was only 37% of that from the control.

Effect of Bioaugmentation on Biogas Yields and Kinetics in Anaerobic Digestion of Sewage Sludge

“…It was due to the differences between the microbial communities of the bioaugmented digesters and the enhanced activity of microorganisms involved in bioaugumentation of anaerobic digestion. This explanation is consistent with the research by Duran et al [31] regarding bioaugmentation with selected strains belonging to Baccillus sp., Pseudomonas sp., and Actinomycetes sp. The slight increase in biogas yields throughout bioaugmentation could result both from the HRT shortening and the TS/VS feedstock dilution by bioaugmenting mixture.…”

Outlining microbial community dynamics during temperature drop and subsequent recovery period in anaerobic co-digestion systems

“…6A). Therefore, the presence of Pseudomonas seems to be also important to lead with low temperatures (Duran et al, 2006). Ruminococcaceae band was weaker with time ( Fig.…”

Bioaugmentation for improved recovery of anaerobic digesters after toxicant exposure

“…For anaerobic processes, bioaugmentation has been investigated at laboratory scale to improve start-up of new digesters (Saravanane et al, 2001a,b), odor reduction (Duran et al, 2006;Tepe et al, 2008), and recovery after organic overload (Lynch et al, 1987). Also, anaerobic degradation rates of phenol and cresol (Charest et al, 1999;Tawfiki Hajji et al, 1999;Guiot et al, 2000;Tawfiki Hajji et al,2000), pentachlorophenol (Tartakovsky et al, 1999;Guiot et al, 2002), 3-chlorobenzoate (Ahring et al, 1992), tetrachloroethylene (Horber et al, 1998) and fat, oil and grease (Cirne et al, 2006) have been increased using bioaugmentation.…”