Phenolic refinery wastewater biodegradation by an expanded granular sludge bed reactor

Water Sci Technol. 2005;52(1-2):391-6.

Abstract

Refinery spent caustics (SC) were diluted with sour waters (SW) in a ratio 1:7, neutralized with CO2 (SC/SW(CO2)) and 83% of H2S was striped during this procedure, remaining an aromatic portion that contained 2123, 2730 and 1379 mg L(-1) of phenol, p-cresol and o-cresol, respectively. The mixture was teated anaerobically in an EGSB reactor fed with 1.5 gCOD L(-1) d(-1), without mineral supplements causing loss of COD removal efficiency that dropped to 23%, methane production ceased and no phenol or cresols were biodegraded. The EGSB experiments were resumed by feeding the reactor with nutrients and phenol at 1.0 gCOD L(-1) d(-1). The mixture SC/SWco2 added to the phenol load, was step increased from 0.10 to 0.87 gCODL(-1) d(-1) maximum. When total organic load was increased to 1.6, COD removal efficiency was 90% and at the highest load attained, 1.87, efficiency dropped to 23% attributed to the toxic effect produced by cresols.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria, Anaerobic / metabolism
  • Biodegradation, Environmental
  • Bioreactors*
  • Carbon Dioxide
  • Hydrogen Sulfide
  • Industrial Waste*
  • Methane / metabolism
  • Petroleum*
  • Phenols / metabolism*
  • Sewage
  • Waste Disposal, Fluid / methods*

Substances

  • Industrial Waste
  • Petroleum
  • Phenols
  • Sewage
  • Carbon Dioxide
  • Methane
  • Hydrogen Sulfide