Tertiary treatment of slaughterhouse effluent: degradation kinetics applying UV radiation or H2O2/UV

Abstract

In some Brazilian regions, surface water has become scarce, e.g. semi arid climate areas and densely populated and industrial areas, where water over-exploitation and/or fluvial pollution has been more common. Advanced oxidative processes (AOP) provide treated water as a source of reuse water even with the characteristics of drinking water enabling water reuse practices also in food industries. The secondary wastewater of a slaughterhouse was the water source for a tertiary treatment study evaluating the kinetics of the photo-induced degradation of color and UV254 under UV radiation with and without the addition of H2O2. The proximity of the k' values of color and UV254 degradation by UV indicates that the compounds responsible for color may be the same content measured by UV254. The H2O2/UV treatment was 5.2 times faster than simple UV in removing aromatic compounds. The degradation kinetics of aromatic compounds in both treatments followed a pseudo-first order law. The pseudo-first order constant for H2O2/UV and UV treatments were kUV254'=0.0306 min(-1) and kUV254'=0.0056 min(-1), respectively.