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Abstract
The most frequent problem encountered in day to day oil well production is the deposition of paraffin or wax inside the production tubing. The solution to this problem is frequent scraping and hot oil operation with help of Coiled Tubing Unit (CTU) thereby increasing the non productive time. The following paper proposes an alternative technique for dewaxing of production tubing.

The technique involves the use of Co-Ni nanoparticles along with an exclusive polymer to be pumped inside the annulus between production tubing and casing at the time of well commissioning. The nanoparticles remain suspended in the polymer filled inside the annulus throughout the life of the well. The application of magnetic field across the casing causes the nanoparticles to vibrate and get heated. This increase in temperature is transferred to the tubing by convection. The increase in temperature causes the wax to melt and is produced along with the oil stream.

This technique will make the frequent scraping and hot oil jobs obsolete thereby saving time and money. The technique eliminates flow assurance problems encountered due to paraffin deposition inside the production tubing.

Paraffin Deposition and Remediation
Paraffin depositions are a source of tremendous monetary loss worldwide due to the enormous cost of prevention and remediation, reduced or deferred production, well shut-in, pipeline replacements and/or abandonment, equipment failures, extra power requirement and increased man power needs.

Paraffin and asphaltene problems vary according to the field and sometimes from well to well in the same field which makes it extremely difficult to have a universally effective solution. Still the problems due to wax deposition are universal. Deposits in the production tubing and surface flowlines gradually choke production and unless removed, the deposited wax eventually stops oil flow. Usually, asphaltenes are also deposited along with paraffin, complicating removal problems.

At reservoir conditions, the paraffin is in solution in the crude oil. As the oil flows to the surface there is a reduction in temperature, pressure and the amount of dissolved gases contained in the oil. The change in the equilibrium conditions reduces solubility of the paraffin in the crude. Lowering of the temperature is the most significant cause of paraffin precipitation. Deposition tends to begin at the point in the system where the temperature of the system falls below its cloud point. The severity of the deposition as well as the location of deposition will depend on the amount of paraffin originally in the crude, the temperature and the pressure at the location. However, precipitation of wax is most severe in the length of tubing near the surface due to the low geothermal gradient and temperature. (Straub, Autry and King, 1989)