Novel Complex Fiber Biofilm Carrier in an Anaerobic/Anoxic/Oxic Reactor for Sewage Mixture Treatment

Abstract

A novel complex fiber filler was designed, which composed of an ultra-fine polypropylene fiber outer-coat and a polyacrylonitrile-based activated carbon fiber felt inner-core. And then the complex fiber filler was used as biofilm carrier in an anaerobic/anoxic/oxic (A²/O) process for sewage mixture treatment to remove organic carbon, nitrogen and phosphorus. During the continuous tests in three Periods, the A²/O biofilm reactor performed well in removing chemical oxygen demand (COD), total nitrogen and total phosphorus. During three period, the influent concentrations of chemical oxygen demand, NH₄⁺-N, total phosphorus and total nitrogen (mg/L) were 954.04 ± 19.45, 143.74 ± 7.66, 23.51 ± 1.52 and 145.50 ± 7.66. The relevant removal efficiencies were 91.86 ± 1.16, 62.46 ± 2.83, 52.51 ± 4.51 and 54.73 ± 3.21 %, respectively; the accumulative rates of NO₃^–-N and NO₂^–-N were 413.72 ± 76.50 % and 1155.64 ± 116.77 %. The novel biofilm carrier has some potential in the A²/O process for removing nutrients from sewage mixture.