Water soluble drag reducer chemicals have enabled significant increases in flow rates in many oilfield water injection systems. In some cases there is concern that this could leads to increased oxygen corrosion whenever the dissolved oxygen concentration strays above a typical injection target such as 20 ppb O2. The effect of a chemical drag reducer on oxygen corrosion of carbon steel was examined in a large scale flow loop simulating a sea water injection line. Drag reduction (up to 48%) matched corrosion reduction (up to 39%). This means that drag reducer has a self compensating effect on oxygen corrosion: it permits higher flow rates without increasing the oxygen corrosion rate.
Keywords: drag, corrosion flow, oxygen, water injection