Controlling Biofilm Formation Through Corrosion Control Agents and Coatings

Abstract

This work explored two primary strategies for controlling biofilm. One method involved the use of sodium silicate as a corrosion inhibitor in a pilot-scale model drinking water distribution system using cast-iron mains. The second method pertained to the use of graphene-enhanced biocidal and foul release (FR) coatings to mitigate biofouling. Biofilm accumulation was evaluated utilizing biological annular reactors (ARs) and microbiological characterization techniques, such as adenosine triphosphate (ATP), heterotrophic plate counts (HPC), protein and carbohydrate concentrations in extracellular polymeric substance (EPS), as well as 16s rRNA sequencing and species identification for bacteria. Biofilm ATP concentrations from the sodium silicate-treated system were lower than the commonly used orthophosphate-treated system. In addition, graphene-enhanced coatings demonstrated the potential to reduce biomass accumulation, however biofilm ATP concentrations did not appear to be affected by an increase in shear stresses from 0.15 to 1.76 N m-2 on the FR coatings.