Novel Low-Temperature Stable Paraffin Inhibitors for Subsea Application

Abstract

One of the most serious flow assurance challenges encountered during oil and gas production is the deposition of paraffins on formation surfaces, flowlines, as well as on other processing equipment. Paraffin deposition can cause problems in the production system that includes blocked pipelines, lower production rates, solids-accumulation, and increased remediation time and costs. Several thermal, mechanical, and chemical methods are used to mitigate these challenges, and, of the chemical techniques available, paraffin inhibitors are deployed to mitigate the deposition problem. Several classes of polymers have been developed into paraffin inhibitors to delay the onset of paraffin precipitation and alter the crystal morphology of the precipitated paraffin particles – these combined phenomena reduce the extent of deposition. While these polymers control wax deposition, several challenges remain for their use in both cold and deep-water environments. Many of these polymers exhibit reduced solubility in common solvents used to formulate treatment products, and, as a consequence can only be blended at low concentrations for use in harsh environments. A real demand exists for new paraffin inhibitors that have enhanced formulation-stability at much higher concentrations suitable for use under low-temperature and high pressure environmental conditions. This paper describes the developmental work and performance evaluation of a novel series of polymers specifically developed for use in low-temperature environments.