Joint treatment of wastewater from table olive processing and urban wastewater. Integrated ozonation-aerobic oxidation

Integrated ozonation-aerobic biodegradation of table olive wastewater (dilu ted 1:25 with synthetic urban wastewater) is presented as a suitable techno logy to purify this kind of effluent. Use of ozone is recommended as a pre- treatment step since it shows a high reactivity toward phenolic compounds ( found in this type of wastewater) reducing, at the same time, the alkalinit y of the media for further biological processing. An ozone dose of 45 mg L- 1 (flow rate 20 L h(-1)) for a period of 35 min has been found to achieve t he following goals: decrease pH, decrease phenolic content, and increase of biodegradability. The aerobic oxidation process followed first order kinet ics as measured by COD depletion profiles versus time. The Arrhenius expres sion k = 183exp(-2214/T) was obtained for experiments of ozonated wastewate r biodegradation completed at different temperatures and neutral pH.