Selection and Preparation of Solvent for Wax Dissolution in Heavy Crude Oil Wells

Abstract

Remedial measures for wax deposition problems in production wells are very hectic due to production down time and expenditure required for removal of heavy and waxy crude oil. Chemical treatment techniques with solvent formulation derived from many laboratory experiments were carried out with the waxy crude oil sample to recover the solidified wax inside the pipelines and wellbores. A list of chemical solvents including three dispersants was mixed in different volumetric compositions to study the solubility of the crude oil. The solvent mixture with optimum solubility among them was identified and suggested for further experiments on a laboratory prototype to measure the production rate at different temperatures ranging from the pour point of crude oil to 90°C. A conclusion was established for the best mixture of solvents for wax dissolution based on availability, toxicity, flammability and other major contributing factors.