A novel integrated system of three-dimensional electrochemical reactors (3DERs) and three-dimensional biofilm electrode reactors (3DBERs) for coking wastewater treatment

Bioresour Technol. 2019 Jul:284:222-230. doi: 10.1016/j.biortech.2019.03.123. Epub 2019 Mar 25.

Abstract

Treatment of coking wastewater is a great challenge due to their instinct characteristics of high concentration, complex composition and biological toxicity. In this work, a novel integrated system comprising three-dimensional electrochemical reactors (3DERs) and three-dimensional biofilm electrode reactors (3DBERs) in series is developed for coking wastewater treatment. Results indicate that 79.63% of COD as well as 76.30% of total nitrogen could be removed at the low energy consumption of 15.6 kWh/m3. 3DERs mainly contribute to COD and nitrogen removal through electrochemical oxidation/reduction, while 3DBERs are responsible for nitrification process by enriched functional microbes. After treating by the integrated system, only long-chain alkanes are left in the wastewater and the toxicity of effluent is significantly reduced. This integrated 3DERs-3DBERs system exhibits capability of simultaneously eliminating carbonaceous and nitrogenous contaminants in coking wastewater, and greatly saves the energy with synergy of electricity and biofilm.

Keywords: Coking wastewater; Energy consumption; Nitrogen; Three-dimensional biofilm electrode reactors (3DBERs); Three-dimensional electrochemical reactors (3DERs).

MeSH terms

  • Biofilms*
  • Bioreactors
  • Coke / analysis*
  • Electrochemical Techniques / instrumentation
  • Electrochemical Techniques / methods*
  • Electrodes
  • Nitrogen / metabolism
  • Oxidation-Reduction
  • Waste Disposal, Fluid / instrumentation
  • Waste Disposal, Fluid / methods*
  • Wastewater / chemistry*

Substances

  • Coke
  • Waste Water
  • Nitrogen