Microbial Ecology of Biofiltration Units Used for the Desulfurization of Biogas

Abstract

Bacterial communities’ composition, activity and robustness determines the effectiveness of biofiltration units for the desulfurization of biogas. It is therefore important to get a better understanding of the bacterial communities that coexist in biofiltration units under different operational conditions for the removal of H2S, the main reduced sulfur compound to eliminate in biogas. This review presents the main characteristics of sulfur-oxidizing chemotrophic bacteria that are the base of the biological transformation of H2S to innocuous products in biofilters. A survey of the existing biofiltration technologies in relation to H2S elimination is then presented followed by a review of the microbial ecology studies performed to date on biotrickling filter units for the treatment of H2S in biogas under aerobic and anoxic conditions.

Special Issue “Advances in Biogas Desulfurization”

“…Le Borgne and Baquerizo [5] present a review on the microbial ecology of biofiltration units for biogas desulfurization. Moreover, a review of the biofiltration technologies is included: conventional biofilter, BTF and bioscrubbers.…”

“…This Special Issue contains the invited submissions to a Special Issue of ChemEngineering on the topic "Advanced Biogas Desulfurization" [1][2][3][4][5]. Three research articles [1][2][3] and two reviews [4,5] have been published. Biogas is a renewable energy source produced by the biodegradation of organic matter under anaerobic conditions.…”

Gaseous emissions from wastewater facilities

“…A review of the main characteristics of sulfur-oxidizing chemotrophic bacteria in aerobic and anoxic BTFs treating H 2 S in biogas was conducted (Le Borgne & Baquerizo, 2019). Anoxic BTFs was recognized as a promising technology since dilution of biogas and explosion risk could be avoided; however, a more intensive sequencing effort was warranted to understand the bacterial communities.…”

Markers for the Comparison of the Performances of Anoxic Biotrickling Filters in Biogas Desulphurisation: A Critical Review

“…Biofiltration is considered more environmentally and economically friendly than physical-chemical methods, as it requires significantly lower chemical use and energy consumption, which translates into a low carbon footprint and lower costs [14]. Thus, H 2 S biofiltration has been researched since the early 1990s [17], being of greater interest in recent years [18]. Biotrickling filters (BTF) are a type of closed biofilter combined with a bioreactor containing a microorganisms culture or a nutrient solution container.…”

“…On the other hand, Tayar et al (2019) evaluated the immobilized biomass of an impure microbial inoculum (anaerobic sludge) in different polymeric packing materials of BTFs, such polyvinyl chloride (PVC) and open-pore polyurethane foam (OPUF), among others, finding that the PVC BTF produced an EC six times higher than that of the OPUF (84.4 gS H 2 S m −3 h −1 and 14 gS H 2 S m −3 h −1 , respectively) in view of the fact that the biomass immobilized in the PVC was 1.7 times less than that of the OPUF (15 and~25.4 mass of protein per mass of dry support (mg g −1 ), respectively) and with the advantage that PVC is cheaper than OPUF [30]. In addition, this is a topic that is closely related to the material chosen to develop the bacterial biofilms in the BTF, demonstrating that the biomass immobilization tests in addition to the EC testing are useful in the selection of suitable packing materials [18]. The problem is that research on anoxic biogas filtration to remove H 2 S has focused on one of these three topics: (a) the concentrations removed by the BTF, (b) the traditional removal parameters (RE, LR, EBRT, and EC) or, (c) the BTF microbial ecology.…”