Ozonation kinetics of winery wastewater in a pilot-scale bubble column reactor.
The degradation of organic substances present in winery wastewater was studied in a pilot-scale, bubble column ozonation reactor. A steady reduction of chemical oxygen demand (COD) was observed under the action of ozone at the natural pH of the wastewater (pH 4). At alkaline and neutral pH the degradation rate was accelerated by the formation of radical species from the decomposition of ozone. Furthermore, the reaction of hydrogen peroxide (formed from natural organic matter in the wastewater) and ozone enhances the oxidation capacity of the ozonation process. The monitoring of pH, redox potential (ORP), UV absorbance (254 nm), polyphenol content and ozone consumption was correlated with the oxidation of the organic species in the water. The ozonation of winery wastewater in the bubble column was analysed in terms of a mole balance coupled with ozonation kinetics modeled by the two-film theory of mass transfer and chemical reaction. It was determined that the ozonation reaction can develop both in and across different kinetic regimes: fast, moderate and slow, depending on the experimental conditions. The dynamic change of the rate coefficient estimated by the model was correlated with changes in the water composition and oxidant species.
Lucas
Marco S
MS
Centro de Química, Universidade de Trás-os-Montes e Alto Douro, Apartado 1013, 5001-801 Vila Real, Portugal. mlucas@utad.pt
Peres
José A
JA
Lan
Bing Yan
BY
Li Puma
Gianluca
G
D001673:Biodegradation, Environmental; D005419:Flavonoids / Q000032:analysis; D006861:Hydrogen Peroxide; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007700:Kinetics; D016877:Oxidants / Q000032:analysis; D010084:Oxidation-Reduction; D010126:Ozone; D010636:Phenols / Q000032:analysis; D010865:Pilot Projects; D059808:Polyphenols; D011174:Portugal; D014865:Waste Disposal, Fluid / Q000379:methods*; D014920:Wine
D005419:Flavonoids; D007220:Industrial Waste; D016877:Oxidants; D010636:Phenols; D059808:Polyphenols; D010126:Ozone; D006861:Hydrogen Peroxide