Corrosion Inhibitors

Controlling corrosion is a big challenge in the oil and gas industry. Easily accessible oil reserves have been depleted resulting in an ever increasing requirement to explore more isolated locations, under harsher conditions. The presence of water, acids, acidic gases, high levels of oxygen and brine all provide the perfect environment for corrosion. This corrosive environment is further complicated by flow conditions, operating temperatures and pressure changes.

Corrosion inhibitors are surfactants which give them properties allowing them to partition between the oil and water phase. The hydrophilic group adsorbs onto the metal surface, which leaves the hydrophobic group to form a water resistant organic film on the surface. It is this film that prevents the corrosive species from coming into contact with the metal surface.

Types of corrosion inhibitors

Water soluble corrosion inhibitors are dosed continuously to maintain a steady concentration of inhibitor, avoiding any loss of production during injection. Oil soluble corrosion inhibitors are successful in high velocity applications. The oil soluble corrosion inhibitor formulation is passed between two pigs to obtain complete coverage of the internal surfaces of the pipe wall.