E. Kudlek
Silesian University of Technology, Institute of Water and Wastewater Engineering, Gliwice, PL


Due to their often high toxicity character, industrial wastewaters are hazardous to the environment. The composition of these type of water streams strictly depends on both their processing, their storage and the industry sector, in which they are produced. One of the commonly used industrial wastewater treatment methods is their dilution and discharging into sewerage system. It does not solve the problem of significant loads of organic and inorganic substances reaching conventional wastewater treatment systems, which are mainly based on activated sludge methods. Laundry wastewater is one of the most problematic water streams, as they contains significant concentrations of anionic, cationic and nonionic surfactants. In this paper the efficiency of the decomposition of organic substances and nonionic surfactants in various configurations of advanced oxidation processes, i.e. UV, UV/TiO2, UV/H2O2 and UV/O3 was evaluated. Before the implementation of the photochemical processes the wastewater was filtered on glass fiber filters (0.45 nm). It has been shown, that the concentration of TOC decrease with the increase in the process time. The highest removal efficiency of nonionic surfactants was observed for the UV/TiO2 process. The process conducted in the presence of TiO2 particles requires the implementation of an additional treatment step to separate the catalyst from the post-reaction mixture. It is not necessary for other UV-based configurations.

Keywords: laundry wastewater, advanced oxidation processes, TOC, surfactants