Investigation of the Impact of Scale Inhibitors: Nonionic Surfactants for Scale Deposition Control in Oilfield

In this work two non-ionic surfactants (1-Octanol ethoxylate (OE-8.7) and Methylcyclohexanol ethoxylate (MCHE-9)) were prepared by the reaction of their hydrophobs with ethylene oxide for using as novel scale inhibitors in oilfield. Their structures were characterized by FT-IR and 1HNMR. Evaluation of the performance of these scale inhibitors was investigated for CaCO3 scale. From the results, the minimum inhibitor concentration (MIC) 10 ppm for scale inhibitor MCHE-9 and 50 ppm for scale inhibitor OE-8.7.The inhibition efficiency of inhibitor MCHE-9 and OE-8.7 were 61.5% and 64.3% at inhibitor dosage of 10 ppm and 50 ppm, respectively. MCHE-9 and OE-8.7, led to modifications in the morphology of scales particles as observed by SEM. These inhibitors distorted the crystal lattice of the precipitates, thus delayed the formation of scales crystal. From the induction time study, inhibitor MCHE-9 had longest induction time of CaCO3 precipitation. Therefore; the scale MCHE-9 is the suitable inhibitor used technically and economically feasible to improve oilfield scale deposition.