Synthesis and evaluation of a new scale inhibitor: the modified epoxysuccinic acid copolymer

Abstract

Polyepoxysuccinic acid (PESA) scale inhibitor is widely recognized as a green and environmentally friendly scale inhibitor. However, its functional group type is single and cannot be used for a variety of scales. Based on this, a modified epoxy succinic acid quaternary polymer scale inhibitor PEAPS was prepared by introducing a variety of functional groups. The effects of scale inhibitor dosage, temperature, and solution pH on the scale inhibition performance of CaCO3, CaSO4, BaSO4, and SrSO4 were studied. At the same time, it is compared with the commonly used oilfield scale inhibitors Polyacrylic acid (PAA), PESA, and Ethylenediaminetetramethylenephosphonic acid (EDTMP). The results show that under the optimal synthesis conditions, the scale inhibition efficiency of PEAPS scale inhibitor on CaCO3 scale and CaSO4 reaches 100%, and the scale inhibition efficiency of BaSO4 and SrSO4 can reach at least 60%. Its comprehensive scale inhibition efficiency is better than other commonly used scale inhibitors under the same test conditions, and it has certain corrosion inhibition performance through static corrosion evaluation. The crystal parameters and micro-morphology of the four scales before and after the addition of scale inhibitor were analyzed using SEM and XRD. The results showed that after adding the PEAPS scale inhibitor, the crystal structure parameters of the CaCO3 scale and CaSO4 scale changed, and the micro-morphology of the four scale crystals also changed, to achieve the purpose of scale inhibition.