Anaerobic semi-fixed bed biofilm reactor (An-SFB-BR) for treatment of high concentration p-nitrophenol wastewater under shock loading conditions

Biodegradation. 2021 Aug;32(4):377-388. doi: 10.1007/s10532-021-09943-0. Epub 2021 Apr 10.

Abstract

P-nitrophenol (PNP or 4-NP) has been widely used as a biorefractory raw material in chemical industry, whereas been highly concerned for its characteristics of mutagenic/carcinogenic activity and food chain bioaccumulation. In this study, an anaerobic semi-fixed bed biofilm reactor (An-SFB-BR) was constructed and used to treat PNP wastewater which discharged from chemical industries. Experimental results revealed that the An-SFB-BR was successfully cultivated with the gradually increasing of influent PNP from 0 to 540 mg/L (gradually increased 10 mg/L every time in stage II and 30-50 mg/L for stage III), with the observation of an average removal efficiency of 98% for PNP and 80% for chemical oxygen demand (COD), also a biogas production and biogas production rate of 2.1 L/(L·d) and 0.57 m3/kg-COD, respectively. Finally, the conversion rate of P-aminophenol (PAP), the primary intermediate of PNP reached 80% after An-SFB-BR biodegradation. A relatively stable pH was maintained throughout the entire process, and insignificant VFA accumulation. The reactor exhibited a strong toxic shock resistance, and 16S rRNA sequencing results demonstrated that the dominant microbial community changed slightly with the gradually increasing of PNP concentration, which guaranteed the PNP removal efficiency.

Keywords: Anaerobic semi-fixed bed biofilm reactor; Microbial community; P-nitrophenol; Toxic shock.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaerobiosis
  • Biodegradation, Environmental
  • Biofilms
  • Bioreactors*
  • Nitrophenols
  • RNA, Ribosomal, 16S / genetics
  • Waste Disposal, Fluid
  • Wastewater*

Substances

  • Nitrophenols
  • RNA, Ribosomal, 16S
  • Waste Water
  • 4-nitrophenol