Coupled photochemical-biological system to treat biorecalcitrant wastewater

• Published in: Water science and technology Vol. 55; no. 12; pp. 95 - 100
• Main Authors: Bacardit, J, García-Molina, V, Bayarri, B, Giménez, J, Chamarro, E, Sans, C, Esplugas, S
• Format: Journal Article
• Language: English
• Published: England IWA Publishing 01.01.2007
• Subjects: 4-chlorophenol; Biochemical oxygen demand; Biodegradability; Biodegradation; Biodegradation, Environmental; Biofilters; Biological activity; Biological effects; Biological treatment; Biological treatment of pollutants; Biology; Biomass; Bioreactors; carbon; Carbon - chemistry; Carbon - metabolism; Chemical oxygen demand; Chlorophenol; chlorophenols; Fenton reaction; filters; Filtration; Hydrogen peroxide; Minerals - chemistry; Minerals - metabolism; optimization; Oxidation; Oxidation process; Photochemicals; Photochemistry; pretreatment; Removal; temperature; Total organic carbon; Total oxygen demand; Wastewater; Wastewater treatment; Water - chemistry; Water Pollutants, Chemical - chemistry; Water Pollutants, Chemical - metabolism; Water Purification - instrumentation; Water Purification - methods
• ISBN: 1843395959; 9781843395959
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.2007.385

The aim of the present work is to study a coupled system to treat biorecalcitrant wastewaters. The combination consists of an advanced oxidation process (AOP) named photo-Fenton (Ph-F), which is a photochemical treatment and a sequencing batch biofilter reactor (SBBR). The synthetic wastewater used to optimise this process is a solution of 200 ppm of 4-chlorophenol (4-CP). The first part of the work is the study of the biodegradability enhancement achieved by the photochemical process, measured as the ratio between the biochemical oxygen demand (BOD5) and the chemical oxygen demand (COD). The second step is the start-up and optimisation of the biological process. The results showed that it is necessary to severely treat the toxic solution (with 500 ppm of [H2O2]0) in order to achieve more than 90% of TOC removal in the whole process. The photochemical and biological treatments lasted 50 minutes and 24 hours, respectively.