title: Stripping as a pretreatment process of industrial oily wastewater.
abstract: In the present work, the potential of purifying an oily wastewater from a lubricant production unit, consisting mainly of alcohols, phenols and heavy linear saturated hydrocarbons, using the stripping process was examined. The effect of stripping gas flow (75-300 L(N2) L(WW)(-1) h(-1)) and system temperature (295-355 K) on the chemical oxygen demand (COD) of the effluent was investigated. A decrease in COD content of 25-30% was achieved after 4 h for stripping gas flow rates over 150 L(N2)L(WW)(-1) h(-1), whereas the rate of organic compounds removal was enhanced by increasing temperature up to 333 K. At higher temperatures an effluent condensation was observed. Gas chromatography-mass spectrometry analysis of both liquid and gas phase showed that linear saturated hydrocarbons of high molecular weight were stripped out from the wastewater. The results are in agreement with the equilibrium ratio of these compounds as predicted from by theoretical calculations.
authors.affiliation: School of Chemical Engineering, Section of Process Analysis and Plant Design, Laboratory of Chemical Process Engineering, National Technical University of Athens, 157 80 Athens, Greece.
authors.forename: S G
authors.initials: SG
authors.lastname: Poulopoulos
authors.forename: E C
authors.initials: EC
authors.lastname: Voutsas
authors.forename: H P
authors.initials: HP
authors.lastname: Grigoropoulou
authors.forename: C J
authors.initials: CJ
authors.lastname: Philippopoulos
mesh_terms: D007219:Industrial Oils; D007220:Industrial Waste / Q000517:prevention & control*; D007700:Kinetics; D008153:Lubrication; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D007220:Industrial Waste; D014874:Water Pollutants, Chemical