Energies (Nov 2021)

Application of Moving Bed Biofilm Reactor and Fixed Bed Hybrid Biological Reactor for Oilfield Produced Water Treatment: Influence of Total Dissolved Solids Concentration

  • Nicolas Lusinier,
  • Isabelle Seyssiecq,
  • Cecilia Sambusiti,
  • Matthieu Jacob,
  • Nicolas Lesage,
  • Nicolas Roche

DOI
https://doi.org/10.3390/en14217297
Journal volume & issue
Vol. 14, no. 21
p. 7297

Abstract

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This experimental paper deals with the development of a hybrid biological reactor for the treatment of a synthetic oilfield produced water under an increase in total dissolved solids (TDS) concentration. To comply with strengthening regulations concerning produced water discharge and peculiar produced water compositions, a moving bed biofilm reactor (MBBR) consisting in a combination of free activated sludge and moving biofilm supports was compared to a fixed bed hybrid biological reactor (FBHBR) consisting in a combination of free activated sludge and a fixed biofilm support. After a 216 days experimental period, the MBBR and the FBHBR were efficient to treat a synthetic produced water with chemical oxygen demand (COD) removal rate above 90% under an increase in TDS concentrations from 1.5 to 20 g·L−1. Ecotoxicity measurements on freshwater and marine microorganisms revealed an absence of toxicity on treated waters. A decrease in bacterial diversity indices with respect to the inoculum was observed in both bioreactors. This suggests that the increase in TDS concentrations caused the predominance of a low number of bacterial species.

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