Advances and challenges of sulfur-driven autotrophic denitrification (SDAD) for nitrogen removal

Activity and growth of SDAD bacteria are affected by factors such as carbon sources, xenobiotics (e.g., Heavy mental and antibiotics) and environmental parameters (e.g., temperature, dissolved oxygen, salinity, etc.). Given appropriate working condition, SDAD may exhibit more powerfully not only in utilizing the N and S substrates, but also minimizing the adverse effects, which perfect its practical application in low C/N ratio wastewater treatment, S0 reclamation and energy harvest, multi-nutrients removal and coupling with other biological nitrogen removal process such as anammox. [Display omitted] Sulfur-driven autotrophic denitrification (SDAD), a process suited for the treatment of nitrogen and sulfur-polluted wastewater without extra supplement of organic carbon, is a promising biological nitrogen removal process. However, the SDAD process was affected by many factors such as various electron donors, organic carbon and exogenous substances (e.g., antibiotics and heavy metal), which prevent further application. Thus, we conducted a detailed review of previous studies on such influence factors and its current application. Besides, a comparative analysis was adopted to recognize the current challenges and future needs for feasible application, so as to ultimately perfect the SDAD process and extend its application scope.