A comparative assessment of the performance of fungal-bacterial and fungal biofilters for methane abatement

Abstract

Methane is an important contributor to global warming and especially for dilute emissions, its oxidation to carbon dioxide can be difficult and expensive. Biofiltration of streams carrying methane at low concentration in air have been treated with biofilters inoculated with methanotrophic bacteria. However, the role of fungi in methane is not well understood.In this work, methane abatement was studied in a biofilter inoculated solely with the filamentous fungus Fusarium solani and compared to a biofilter inoculated with a consortium of methanotrophic bacteria (Methylomicrobium album and Methylocystis sp) and F. solani.Results showed that F. solani degrade methane as the sole carbon source, achieving a maximum elimination capacity of 42.2 g m -3 h -1 , nearly half of the maximum elimination capacity of the fungal-bacterial consortium. Co-feeding o methane and n-pentane, a highly hydrophobic and easily degradable VOC, further improved the elimination capacity of both biofilters, with the elimination capacity of the fungal biofilter surpassing the one attained by the fungal-bacterial biofilter.A concise mathematical model of the biofilter together with the evaluation of the second Damköhler number indicated that under the operational conditions here applied, the fungal biofilter performance was bioreaction limited meanwhile external mass transport limitation was found on the fungal/methanotrophic bacteria biofilter.These results, and the estimated mass transfer coefficients, suggest that the beneficial effect of F. solani during CH4 biofiltration was mediated by biomass hydrophobicity rather than to the formation of aerial hyphae structures increasing the mass transfer area.

Bio-Drying of Municipal Wastewater Sludge: Effects of High Temperature, Low Moisture Content and Volatile Compounds on the Microbial Community

“…Fusarium fungi are practically the only ones in the biofilter (99.6%). It is reported that Fusarium solani were inoculated into biofilters and were able to oxidize toluene [80], methane [81], pentene, hexane [82] and dimethyl sulfide [83]. The presence of the above-mentioned microorganisms in biofilter provided removal of VOCs from the waste air from WS bio-drying by more than 90%.…”

A radial‐flow device for the biopurification of a model VOC‐ and wood‐smoke‐ contaminated confined space

“…To calculate the refreshment capacity (⊍) and removal efficiency (effectiveness, R) of the purifier, the pollutant gas concentrations in the inlet and outlet streams of the hermetic chamber were determined by gas chromatography according to Morales et al 20 After 8 months of operation of the biopurifier, samples of the packaging material were taken to be analyzed by scanning electron microscopy (SEM) after drying at 105 °C for 24 h. Subsequently, the samples were mounted and visualized, as previously reported. 25…”

“…After 8 months of operation of the biopurifier, samples of the packaging material were taken to be analyzed by scanning electron microscopy (SEM) after drying at 105 °C for 24 h. Subsequently, the samples were mounted and visualized, as previously reported 25 …”