Optimum hydraulic retention time, the best microbial community genus, and carbon sources in woodchip denitrifying bioreactors: a mini review

Different factors affect the performance of denitrifying bioreactors. Hydraulic retention time (HRT), carbon source, and microbial community genus are three of the most important factors that affect the performance of denitrifying bioreactors. This study aimed to evaluate the best possible case of these factors. So, this study reviewed 43 papers between 2016 and 2023. Woodchips with 50% of particles >13 mm are recommended to be used in denitrifying bioreactors. Also, sedge, straw, and potato residues have better performance in comparison with woodchip. It can be seen that the performance of bioreactors is optimized at HRTs higher than 24 h. Microbial community genus belongs to Pseudomonas family bacteria, and Thauera and Halomonas species have an acceptable efficiency in unfavorable conditions.