Application of Combined Coagulation–Flocculation–Decantation/Photo-Fenton/Adsorption Process for Winery Wastewater Treatment †

Abstract

In the present work, winery wastewater (WW) was treated by a combined coagulation–flocculation–decantation (CFD)/photo-Fenton/adsorption process. The aim of this work was to (1) optimize the CFD process with the application of polyvinylpolypyrrolidone (PVPP); (2) optimize the photo-Fenton process; (3) evaluate the efficiency of combined CFD/photo-Fenton/adsorption process. Under the best conditions ([PVPP] = 0.5 g/L, pH = 6.0, rapid mix (rpm/min) = 150/3, slow mix (rpm/min) = 20/20, sedimentation 12 h), the CFD process achieved a total organic carbon (TOC) of 46.9 %. With the application of photo-Fenton ([Fe2+] = 2.5 mM/[H2O2] = 225 mM/ pH = 3.0), a TOC removal of 69.1 and 76.0%, respectively, for UV-A and UV-C radiation was achieved. Electric energy per order (EEO) achieved 641 and 170 kWh m−3 order−1, respectively. The application of adsorption ([Bentonite] = 1.5 g/L, pH = 6.0, agitation = 350 rpm, sedimentation = 2 h) achieved a TOC removal of 72.0 and 76.0%, respectively. In conclusion, the combined treatment is energy efficient for WW treatment.