MABR-based SPND biofilms

Three biofilms were formed under different concentration of carbon sources to treat low COD/N wastewater with high-strength ammonia nitrogen in MABRs. Ammonia-oxidizing bacteria (AOB) and archaea (AOA) both contributed to nitrification, and NOB were incompletely suppressed. When carbon sources were not sufficient, the microbial community tended to secrete more EPS to protect themselves in a poor nutritional environment, and the abundance of EPS-secretion bacteria decreased with the increased carbon sources. The abundance of nitrifying microorganisms decreased with the increased carbon sources, which was consistent with the decreased ammonia removal efficiency.