Experimental evaluation of corrosion inhibitors for completion fluids in the petroleum production systems

AbstractCorrosion is the natural and continuous degradation of materials caused by either chemical, mechanical, or electrochemical reactions. Corrosion inhibitors may be added to the completion fluids to address corrosion problems efficiently. It is critical to add corrosion inhibitors in completion fluids, specifically under high-temperature conditions, since the corrosion rate is higher when the temperature is high. This corrosion process limits the life of the drill tools or the oil and gas well and causes formation damage. This research studied corrosion and corrosion inhibition treatments for five completion fluids, namely potassium chloride, sodium chloride, sodium bromide, calcium chloride, and calcium bromide. Phosphate and sulfite-based corrosion inhibitors were individually added to the completion fluids, and their corrosion properties were studied to tackle the corrosion issue. In addition, a mixture of phosphate-based and sulfite-based corrosion inhibitors in completion fluids was studied. Additionally, the experimental results recommend using divalent brines as they were identified as a better medium for lowering corrosion rate and conditions than the monovalent brines. A novel aspect of this study is that the materials leveraged for conducting experiments are also used in actual petroleum production field operations. The experiments demonstrate that the corrosion rate can be efficiently controlled at high temperatures in deeper wells.