Solar Fenton: from pilot to industrial scale application for polishing winery wastewater pretreated by MBR

Abstract

BACKGROUND Depending on the nature of the pollutants and the level of contaminants, detoxification of various industrial effluents, as well as winery wastewater, might be difficult and/or even impossible to achieve by single conventional biological methods. In such cases, biological processes alone are not able to reach effluent standards for discharge into the environment, and therefore, a pretreatment or post-treatment is required. In this study, winery effluent already treated in a membrane bioreactor (MBR) was subjected to further treatment by a solar Fenton oxidation process, at pilot and industrial scale. RESULTS The optimum Fe2+ and H2O2 concentration was found to be 3 mg L−1 and 350 mg L−1, respectively. Solar Fenton oxidation has been demonstrated to be an effective process both at pilot and industrial scale, yielding after 180 min of photocatalytic treatment removals of COD, DOC and color of about 85%, 62–68%, and ∼80%, respectively. CONCLUSIONS The combined MBR + solar Fenton process seems to be an effective technology for winery wastewater treatment, that can reduce the organic pollutants in the winery effluent to values below that of the Cypriot discharge limits. Moreover, solar Fenton treatment was proved capable of eliminating the toxicity to D. magna, and significantly reducing the phytotoxicity at values well below the starting values induced by the raw effluent. © 2013 Society of Chemical Industry