Comparative Performance of Biocides versus Corrosion Causing Biofilms

Biofilms can cause severe problems in oilfield water systems.  The biocidal efficacy of several common oilfield biocides was evaluated versus a defined microbial biofilm.  In addition to their biocidal performance, the biofilm removal properties of the biocides were determined using epifluorescent microscopy.  The comparative biocidal testing showed that the amphipathic phosphonium quat tributyl tetradecyl phosphonium chloride (TTPC) was more effective versus biofilm microorganisms than the non- amphipathic THPS.  TTPC also showed better biofilm removal properties than THPS and glutaraldehyde on a ppm active basis.  Biocides with good biofilm removal properties will reduce corrosion both directly by reducing MIC and indirectly by exposing surfaces allowing corrosion inhibitors to be more effective.  An effectiveness ranking for biocides versus biofilm was developed.