Thesis Title: Tannery wastewater treatment with Photo-Fenton oxidation
Thursday 5 July 2018, at:13:00, Venue: Hall Κ2. Α3
Examination Committee
- Professor Evan Diamadopoulos (advisor)
- Assistant Professor Nikolaos Xekoukoulotakis
- Assistant Professor Paraskevi Panagiotopoulou
Abstract:
This paper investigates the treatment of tannery waste-water. Samples were obtained from the Vrontakis Tannery in Chania. Leather is a well-known organic matter, so its processing wastes are expected to contain a high organic load. For this reason, wastewater treatment becomes necessary before it is discharged into the environment. The method chosen for the treatment of this type of wastewater in thiw work, is Fenton oxidation under conditions of absence or presence of light (Photo Fenton).
The leather processing steps of a typical tannery unit, as well as the produced wastewater are be in mentioned in the first part of the theoretical background. The second part analyzes the mechanisms of Fenton and Photo-Fenton oxidation as well as the factors that affect them. In the third part, reference is made to other studies which have been carried out on tannery wastewater using Photo-Fenton. Finally, a description of the specific tannery and the sampling campaign, are mentioned.
The experimental part presents two series of experiments: The first series aims to determining the optimal dose of ferrous (Fe2+) and the ratio of iron to hydrogen peroxide ratio (Fe2+: H2O2) in the presence and absence of light. Because the samples contained suspended solids, a set of experiments was conducted with filtered samples for comparison purposes. In the second series, kinetic experiments were carried out at the optimal doses of ferrous (Fe2+) and ferric (Fe3+) salts under optimal Fe: H2O2 ratio as resulted from the first series of experiments, in the presence and absence of light.
Treatment efficiency was evaluated by the percentage of dissolved organic carbon (DOC) removal. In particular, for the first sample the optimal conditions were: Fe2+ dose 2 g/L and Fe: H2O2 ratio 1:20. This achieved, 84.4% and 81.0% removal of DOC under conditions of absence and presence of light, respectively. For the second and third samples, the optimal Fe2+ dose was 2 g/L and the ratio 1:50. For the second sample DOC removal was 62.2% and 71.9%, while for the third sample 77.7% and 78.3%, under conditions of absence and presence of light, respectively.
