Solar treatment of cork boiling and bleaching wastewaters in a pilot plant

Water Res. 2009 Sep;43(16):4050-62. doi: 10.1016/j.watres.2009.06.019. Epub 2009 Jun 16.

Abstract

This paper reports on cork boiling and bleaching wastewaters treatment by solar photocatalytic processes, TiO(2)/UV and Fe(2+)/H(2)O(2)/UV (TiO(2)-only for bleaching wastewater), in a pilot plant with compound parabolic collectors. The photo-Fenton reaction (k=0.12L/kJ(UV), r(0)=59.4 mg/kJ(UV)) is much more efficient that TiO(2) photocatalysis and TiO(2)+S(2)O(8)(2-) (k=0.0024 L/kJ(UV), r(0)=1.36 mg/kJ(UV)), leading to 94% mineralization of the bleaching wastewater after 31.5 kJ(UV)/L, consuming 77.1mM of H(2)O(2) (3.0 mmol/kJ(UV)) and using 20 mg/L of iron. For the cork boiling wastewater, after a slow initial reaction rate, the DOC degradation curve shows a first-order kinetics behaviour (k=0.015 L/kJ(UV), r(0)=20.8 mg/kJ(UV)) until 173 kJ(UV)/L ( approximately 300 mgC/L). According to the average oxidation state (AOS), toxicity profiles, respirometry and kinetic results obtained in two solar CPCs plants, the optimal energy dose estimated for phototreatment to reach a biodegradable effluent is 15 kJ(UV)/L and 114 kJ(UV)/L, consuming 33 mM and 151 mM of H(2)OT:/PGN/ELSEVIER/WR/web/00007490/(2), achieving almost 49% and 48% mineralization of the wastewaters, respectively for the cork bleaching and boiling wastewaters.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aliivibrio fischeri / drug effects
  • Hydrogen Peroxide / analysis
  • Hydrogen Peroxide / chemistry
  • Industrial Waste / analysis*
  • Iron / chemistry
  • Kinetics
  • Photolysis
  • Quercus
  • Sunlight*
  • Titanium / chemistry
  • Toxicity Tests
  • Waste Disposal, Fluid / methods*
  • Water / chemistry
  • Water Pollutants / chemistry*
  • Water Pollutants / radiation effects*
  • Water Pollutants / toxicity
  • Water Purification / methods

Substances

  • Fenton's reagent
  • Industrial Waste
  • Water Pollutants
  • Water
  • titanium dioxide
  • Hydrogen Peroxide
  • Titanium
  • Iron