Demulsification of water-in-oil emulsion by wetting coalescence materials in stirred- and packed-columns

Abstract

Demulsification of emulsified water-in-oil droplets was developed using wetting coalescence materials. Demulsification tests were carried out using conventional stirred- and packed-columns. Of the four kinds of natural fibers and two kinds of inorganic materials tested, natural fiber A, selected from shaves of a wood showed the best performance in demulsification. The demulsification efficiency can exceed 97% when demulsification conditions are optimized. The packed-column showed much better performance both in terms of demulsification efficiency and repeated use of the recovered oil phase for extracting cadmium in a simulated wastewater. Operating variables that govern the demulsification efficiency were investigated. (C) 1999 Elsevier Science B.V. All rights reserved.