The use of polymers in the treatment of produced oily waters

In this work, a new flocculant agent was developed based on a non‐ionic and water‐soluble polymer, poly(vinyl alcohol) (PVA), in order to treat oily waters from peteroleum production. Changes on its HLB were made to generate hydrophobic zones that work like flocculant agents, based on “hydrophobic bridges mechanism.” Incorporation of 12 to 18 carbon atoms and carbamate groups in several concentrations were carried out. Little insertions of hydrophobic groups reduce the brine solubility, due to the inter‐ and intramolecular interactions; however, certain content of carbamate groups increases the resistance in a brine environment. The influence of molecular weight and the hydrolysis grade of PVA were verified as the flocculation efficiency. Their performance was verified in synthetic oily emulsion by flocculation tests. The flakes generated are different from those generated when using commercial products. High amount of additive decreases the flocculation efficiency. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1473–1479, 2004