Polymeric Surfaces for Heavy Oil Pipelines To Inhibit Wax Deposition: PP, EVA28, and HDPE

Abstract

Pipelines for heavy crude oils have recurrent clogging situations due to paraffin deposition that may lower production rates and be responsible for leakages. This work evaluates the effect of three polymers on crude oil wettability and on paraffin deposition inhibition: polypropylene (PP), high-density polyethylene (HDPE), and a vinyl acetate copolymer with 28% oxygen content (EVA28). Under static conditions, the interfacial tension between the crude oil and the linings was determined by the contact angle being 12% and 17% higher for EVA28 and HDPE, respectively, than for that of PP. As the crude oil inside the pipelines is flowing at high rates, the dynamic interfacial tension was also observed for high flow rates when molecular effects overtake hydrodynamic ones. For this, the perturbation of intermolecular orientation within the flow, caused by the beginning of deposit formation and by the wettability, was determined using depolarization of the fluorescence induced by laser. Under flow, EVA28 and HDPE...