Increasing Treatment Lifetime through Sustained Release of Scale Inhibitor from Scale Inhibitor Nanoparticles

Summary Scale can cause flow assurance issues because of damage to the near-wellbore region and in production facilities. Scale inhibitors are often used to help mitigate these problems. The main focus of this proof-of-concept study is to examine the ability of a newly developed crosslinked nanosized scale inhibitor (NSI) particle to inhibit scale formation through sustained release of scale inhibitor into a model brine and increase scale inhibitor treatment lifetime. Results from minimum inhibition concentration (MIC) measurements showed that, at 95°C, the MIC decreased gradually from 10 ppm at day 0 to 5 ppm after 9 days and eventually reached a very low MIC of 2 ppm after 49 days. These findings are consistent with our hypothesis that the sustained release of linear scale inhibitor from the NSI would result in a decrease in MIC over time caused by an increased amount of linear scale inhibitor being released into the model brine. Also, attaching 2-acrylamido-2-methyl-1-propanesulfonic functional group (AMPS) to NSI successfully inhibits the pseudoscale formation when the scale inhibitor comes into contact with the calcium and magnesium in the model brine. Results from sandpack floods showed that NSI increased the treatment lifetime from 3 pore volumes (PV) postflush throughput, for the traditional scale inhibitor, to 35 to 105 PV postflush throughput. These results support our hypothesis that sustained release of the trapped NSI nanoparticles can improve the treatment lifetime.