Abstract
Abstract
When oil producers start producing water, a variety of issues arise. This includes decline in oil production rates, corrosion, emulsion, and is coupled with inorganic scale precipitation. One common treatment in such scenarios is a scale inhibitor squeeze. Scale inhibitor squeeze treatments are very effective and can prevent precipitation of scale during production for an extended period of time. This work will discuss the lab and field tests required for a scale inhibitor squeeze job in an oil producer.
Compatibility tests between the scale inhibitor and the downhole fluids were conducted using static lab experiments and an inorganic scale prediction software. Additionally, HPHT coreflood was utilized to determine the compatibility between the scale inhibitor squeeze treatment and the downhole rocks at 200°F. Moreover, thorough well completion components, completion settings, mineralogy, and productivity indices were assessed before and after the scale inhibitor squeeze job.
The results showed that the scale inhibitor squeeze treatment worked as intended, exhibiting no incompatibility issues between the used scale inhibitor and the downhole rocks or fluids such as downhole oil and downhole water. However, it was noted that when the amount of scale inhibitor was excessive in the coreflood tests, it produced significantly higher precipitation at the core inlet which led to an increase in pressure drop. Consequently, bullheading excessive amounts of scale inhibitor is not recommended. Following this analysis, a carefully controlled scale inhibitor squeeze is advised through a coil tubing targeting the zone of interest where the inhibitor was intended to be used.
This work shares the tests and the analysis that needs to be done to successfully place a scale inhibitor squeeze job in an oil producer. This study proved that a full understanding of the well components, fluids, and rock properties is critical.