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.

The degradation products of the macrolide antibiotic erythromycin A (ERY) arising from direct ozone attack and hydroxyl radical attack are presented for the first time. Ozone treatment was carried out by spiking ozone stock solutions to solutions containing ERY-ERY:O 3 5 1:5 and 1:10 (M:M), while, in parallel, t-BuOH was used as a hydroxyl radical (NOH) scavenger. The advanced oxidation processes (AOPs) O 3 /UV, O 3 /H 2 O 2 , and UV/H 2 O 2 were carried out to recognize and verify possible differences between their primary degradation products; the initial concentrations were ERY:O 3 5 1:5 (M:M), ERY:O 3 :H 2 O 2 5 1:5:5 (M:M:M), or ERY:H 2 O 2 5 1:5 (M:M), respectively. Six degradation products were identified from ozonation-one originates from direct ozone attack on the tertiary amine group, while the others arise from radical ion attack, which might be formed during degradation of O 3 in water. Fewer primary degradation products were observed arising from NOH-based treatments (AOP) than from ozonation, possibly because the reaction of NOH radicals is non-selective and typically is diffusion-controlled. Four degradation products were detected by NOH radical attacks; two of them already were observed during ozonation, with one as an oxidized ERY molecule and the other as a non-oxidized fragment of the ERY molecule. Water Environ. Res., 82, 797 (2010).

Four tertiary hybrid treatments to produce high quality reused water, fulfilling Brazilian drinking water regulations, from a slaughterhouse's secondary treated effluent were evaluated. The pilot plant with a capacity of 500 L h(-1) was set up and consisted of these stages: pre-filtration system (cartridge filter 50 micron, activated carbon filter, cartridge filter 10 micron), oxidation (H2O2) or second filtration (ceramic filter, UF) followed by UV radiation (90 L h(-1)). The best combination was T4: pre-filtration followed by H2O2 addition and UV radiation (AOP H2O2/UV). Disinfection kinetics by T4 followed pseudo first-order kinetics: k(T4) = 0.00943 s(-1) or 0.00101 cm2 mJ(-1). Three different zones (A, B, C) were observed in the UV254 degradation kinetics (pseudo-first order kinetics): k' decreased over time (k'(A) > k'(B) > k'(C)).

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Industrially, many solid wastes can be classified as biomass and their usage reduces disposal costs. In this work, seven wastes from textile and food industries were characterized chemically and physically and the gaseous emissions resulting from the combustion of three of them (textile residues 3, TR3; coffee grounds; and a mixture of meat processing industry wastewater sludge and saw dust (1:9) in weight, SS1) in a pilot scale cyclone type combustor were measured. Their potential for utilization as energy sources was assessed by comparing the emissions to current legislation. Chemical properties showed that the volatile matter values of all biomass were high, which indicate that the solids burn rapidly. Some biomass presented high levels of sulfur and consequently high levels of SO2 emission when burned. The lower heating values ranged from 6.44 MJ kg−1 (dry and ash free, daf) to 22.93 MJ kg−1 (daf) and thermogravimetric analysis of the biomasses showed ignition temperatures and maximum burning rates, which were compared with other papers’ data. Four combustion tests were carried out in a cyclone type combustor and CO, CO2, NOx, CxHy, and SO2 were measured. Moisture content and particulate matter were also measured during the combustion tests and showed effective combustion conditions. Volatile organic compounds were analyzed by gas chromatography-mass spectrometry and their content values were expressed as total organic carbon (TOC), being all TOC emissions below the limits imposed by the regulations taken as reference. Gaseous emissions were compared with limits imposed by Brazilian and international current legislations, what showed that the usage of these biomasses as energy sources is possible; however, gas treatment would be required, especially if the solid presents high levels of sulfur and chlorine.