Performance of Chemical Catalytic Biofilm Technology for Decentralized Sewage Treatment.

The decentralized sewage discharge changes greatly in quantity, quality, and spatial distribution, and is becoming increasingly intractable. Therefore, a chemical catalytic biofilm reactor (CCBR) was established with an iron-based microbial coupling carrier and applied to treat domestic sewage. The dynamic features of the CCBR were examined along with the effects of the hydraulic retention time (HRT), dissolved oxygen (DO), and recycle ratio on pollutant removal. An optimal DO content of 4.0 mg/L, HRT of 7.5 h (4.5 h for anaerobic biological reactor and 3.0 h for aerobic biological reactor), and recycle ratio of 4:1 were obtained at total nitrogen, chemical oxygen demand (COD), and total phosphorus (TP) removal efficiency levels of ∼91.7–94.1%, ∼95.4–97.0%, and ∼88.9–93.3%, respectively. Simultaneous heterotrophic and autotrophic denitrification occurred in the CCBR as revealed by analysis of the microbial communities. Thus, the CCBR shows great potential for application in decentralized domestic sewage treatment systems. [ABSTRACT FROM AUTHOR]