Reza Azin

In this work, we studied the feasibility of using disulfide oil (DSO) as a solvent for wax prevention in pipelines. Several tests were carried out to determine the effects of DSO, ethylene-vinyl acetate (EVA), acetone, and p-xylene and their mixtures on wax appearance temperature (WAT), deposition mass, and rheological properties of oil samples. The WAT was determined from viscosity in the temperature range of 2–40 °C with 1 °C min?1 cooling rate. Viscoelastic modulus of different samples was measured at temperature intervals of 25–65 °C with 0.5 °C min?1 cooling rate. Results indicated that DSO has a good potential for reducing WAT and wax deposition mass; however, increasing DSO concentration to higher than 800 ppm did not show a significant effect on deposition reduction. It was found that a mixture of inhibitors had higher impact on reducing wax deposition. Using 800 ppm of EVA–DSO–acetone mixture resulted in deposition mass reduction to about 35.74%. It was found that the strong original gel network was considerably weakened by addition of DSO.