Sustainable treatment of industrial waste air using two-phase partitioning bioreactors and microbial composition shifts during the long-term operations

Biological treatment methods are considered as promising, environmentally friendly, and cost-effective technologies for the treatment of volatile organic compounds (VOCs) from the industrial waste air. The hydrophilic pollutants, e.g., alcohols, ketons, etc., are removed effectively using common bioreactor configurations containing a bulk of water for the absorption of target compound from the air and subsequent biodegradation by the associated microorganisms. However, the removal efficiencies of hydrophobic pollutants, e.g., volatile aromatic and aliphatic hydrocarbons, decreased significantly since they are not water-soluble compounds. Two-phase partitioning bioreactors (TPPBs), including a water-immiscible and non-biodegradable organic phase, have been introduced in the past decade to overcome this mass transfer challenge. On the other hand, the simultaneous presence of hydrophilic and hydrophobic compounds in the produced waste air of some industries provides complex environmental effects on the microbial community, regarding the interactions between the components and the associated groups of microorganisms involving in the biodegradation process. This lecture focuses on the design and operation of TPPBs along with the microbial composition shifts in these systems during long-term operations.