Performances, mechanisms, and strategies for methane removal via gas biofiltration

Abstract

Control of methane emissions has attracted widespread attention in the context of worldwide efforts to alleviate the greenhouse effect. Biofiltration, a green and cost-effective treatment process, has been widely used for the purification of methane. Currently, there is still a lack of comprehensive information on methane biofiltration. Herein, the state-of-the-art development trends of methane removal via biofiltration were comprehensively reviewed and commented on. First of all, this article reviewed the mechanisms of methane removal and the possible degradation pathways in biofilters. Secondly, the removal characteristics of single methane, methane mixed with volatile organic compounds or gaseous inorganic compounds by biofiltration, were summarized and discussed. Thirdly, the practical applications of methane biofiltration were summed up and some inspirations were proposed. Finally, the effective measures to improve the performance of methane biofiltration were put forward, and corresponding insights and future research directions for methane biofiltration were provided. This article can provide references for the practical applications of methane biofiltration and the mitigation of greenhouse effects.

Graphical abstract

Keywords

Biofilter / Methane / VOC / Greenhouse effect / Carbon reduction

Highlight

	● Mechanisms and removal pathways of CH4 via biofiltration were reviewed and discussed.
	● Interactions between methane and coexisting substances were examined and described.
	● Applications and inspirations of CH4 biofiltration were put presented and analyzed.
	● Strategies for enhanced removal of methane by biofiltration are proposed.

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