Rotating Biological Contactor Reactor with Biofilm Promoting Mats for Treatment of Benzene and Xylene Containing Wastewater

A novel rotating biological contactor (RBC) bioreactor immobilized with microorganisms was designed to remove volatile organic compounds (VOC), such as benzene and xylene from emissions, and its performance was investigated. Gas-phase VOCs stripped by air injection were 98?% removed in the RBC when the superficial air flow rate was 375?ml/h (1,193 and 1,226?mg/l of benzene and xylene, respectively). The maximum removal rate was observed to be 1,007 and 1,872?mg/m³/day for benzene and xylene, respectively. The concentration profile of benzene and xylene along the RBC was dependent on the air flow rate and the degree of microbial adaptation. Air flow rate and residence time were found to be the most important operational parameters for the RBC reactor. By manipulating these operational parameters, the removal efficiency and capacity of the bioreactor could be enhanced. The kinetic constant K _s demonstrated a linear relationship that indicated the maximum removal of benzene and xylene in RBC reactor. The phylogenic profile shows the presence of bacterium like Pseudomonas sp., Bacillus sp., and Enterococcus sp., which belonged to the phylum Firmicutes, and Proteobacteria that were responsible for the 98?% organic removal in the RBC.