The Effect of Inhibitor on Wax Precipitation in Iranian Oil Fields Using Differential Scanning Calorimetry and Microscopy Methods

In this study, effect of ethylene vinyl acetate (EVA) as an inhibitor on wax appearance temperature (WAT) of crude oil in the Iranian oil field has been investigated using differential scanning calorimetry (DSC) method. The effect of EVA on the morphology of crude oil wax crystals has been investigated using a system designed to be equipped with an ocular microscope. The EVA inhibitor has a very good performance in reducing the Wax appearance temperature of crude oil and by adsorbing on the growing wax crystals, it prevents the crystallization process and also their connection to each other to form a network structure. By 800 ppm of the EVA inhibitor, the largest decrease occurred in the WAT of crude oil (at the rate of 26.13 ° C) and also smaller crystals and weaker structures were formed at this concentration. Therefore, 800 ppm of EVA inhibitor was selected as an optimal value